104 results on '"MOLYBDENUM"'
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2. MOLIBDÊNIO NO METABOLISMO E DINÂMICA VEGETAL: UMA REVISÃO.
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Vaz Alves, Silvana Rodrigues and da Silva Berti, Mariana Pina
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SODIUM molybdate ,NITROGEN fixation ,NITRATE reductase ,MOLYBDENUM oxides ,PLANT metabolism ,MOLYBDENUM - Abstract
Copyright of Revista Agrotecnologia is the property of Universidade Estadual de Goias and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2022
3. Scientific Electronic Archives OPEN JOURNAL SYSTEMS Ajuda do sistema USUÁRIO Logado como: berber Perfil Sair do sistema NOTIFICAÇÕES Visualizar (122 nova(s)) Gerenciar IDIOMA Selecione o idioma CONTEÚDO DA REVISTA Escopo da Busca Procurar Por Edição Por Autor Por título TAMANHO DE FONTE Make font size smallerMake font size defaultMake font size larger INFORMAÇÕES Para leitores Para Autores Para Bibliotecários CAPA SOBRE PÁGINA DO USUÁRIO PESQUISA ATUAL ANTERIORES NOTÍCIAS Capa > v. 12, n. 1 (2019) > Santana Soy productivity in response to application biofertilizer Enerplant®.
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D. P. Thome, A. G. Carneiro Júnior, V. L. Silva, E. P. S. Silva, and M. B Gomes
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Productivity ,Molybdenum ,Oligosaccharides ,Biofertilizer ,Soya ,General Works - Abstract
The soya is a dicotyledon plant, and the cultivated specie is the Glycine max, of Asian origin especially from China. The Brazil is the second biggest worldwide producer, with featured the Mato Grosso state. The objective of this present study was evaluate the productivity in the soya culture in answer of Enerplant Biofertilizer application. The experiment was realized in a trading farming, in soil classified like Latossolo Vermelho, in conditions of system of direct planting of straw. The Treatments consisted on application in g ha-1 of Enerplant in the seed, V4, V7 and R1 respectively: T1 – 0+0+0+0; T2 – 20+20+20+20; T3 – 20+20+20+20; T4 – 20+20+0+0; T5 – 20+0+0+0; T6 – 40+0+0+0; T7 – 80+0+0+0; T8 – 0+20+20+20; T9 – 0+0+20+20; T10 – 0+0+0+20. The treatments had four repetitions, on parcels of 2,25 x 5 m (11,25 m²) with five planting lines disposed in a casualized blocks delimitation (CBD). The fertilization in dosage of 160 kg ha-1 of the 01-42-00 (N-P2O5 – K2O) formula and 160 kg ha-1 of KCl. Were evaluated the number of pods from one, two and three grains, total number of pods, total number of grains, weight of 100 grains, pods number per plant, grains number per pod and productivity in kg ha-1. In the Analysis of the results, show there was no significant difference of any variables studied, dispensing the product application
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- 2019
4. Direct determination of aluminum in low-enriched UAlx targets (UAlx-Al) by Inductively Coupled Plasma Optical Emission Spectrometry
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Sabine Neusatz Guilhen, Alexandre Luiz de Souza, Marycel Elena Barboza Cotrim, and Maria Aparecida Faustino Pires
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UAlx ,molybdenum ,ICP OES ,spectral interference ,Science - Abstract
The production of molybdenum-99 (99Mo) using low-enriched uranium targets (< 20% 235U) dispersed in aluminum (UAlx) is a very promising strategy towards the independence in 99Mo local production. A thorough control must be performed to ensure that these targets meet the regulatory requirements to achieve the expected efficiency in the reactor. The determination of the targets’ composition is of high interest, because the distribution of Al in different phases may have an impact on the U concentration. Among the techniques used for this purpose, inductively coupled plasma optical emission spectrometry (ICP OES) stands out because of its high sensitivity and precision, allowing for simultaneous determination of several elements in a variety of samples and matrices. However, because U exhibits a complex emission spectrum, spectral interferences are prone to affect the analysis of Al, calling for time consuming preparation steps to remove the U from the matrix. This study proposes a method of direct determination of Al in UAlx targets through the selection of specific emission lines enabled by the evaluation of the associated interferences on the recovery values.
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- 2021
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5. Remoção do alaranjado de metila em meio aquoso por microcristais de h-MoO3 obtidos pelo método micro-ondas hidrotérmico.
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de Sá, M. L., Nobre, F. X., de Matos, J. M. E., and Santos, M. R. M. C.
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INDUSTRIAL wastes ,ADSORPTION capacity ,TRIOXIDES ,ADSORPTION (Chemistry) ,MOLYBDENUM ,MICROWAVE heating - Abstract
Copyright of Ceramica is the property of Associacao Brasileira de Ceramica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
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- 2020
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6. NITROGEN, SULFUR, MICRONUTRIENTS AND INOCULANT IN THE CULTIVATION OF IRRIGATED BEANS IN MATO GROSSO
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A. Lange, A. C. Buchelt, O. A. Kobeliski, E. Cavalli, F. J. Wruck, and G. Caione
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Phaseolus vulgaris ,nitrogen ,cobalt ,molybdenum ,General Works - Abstract
This study to evaluate the effects of nitrogen (sources and doses), sulfur, micronutrients and inoculant in the common bean BRS Valente cultivar on winter irrigated crop because in this situation the wrong dose of N at seeding may cause immobilization of the nutrient in the soil and temporary deficiency of N in bean. The experiment took place in 2011, in the city of Sinop – MT, JF farm in the experimental design was randomized blocks with four replications and twelve treatments combining N rates up to 160 kg ha-1, sulfur and inoculation. The following characteristics were evaluated: plant height, height of the first pod, number of seeds per pod, number of pods per plant, 100-seed weight, grain yield in kg ha-1, nitrogen sufficiency index and SPAD index, nitrogen contents in leaf, seeds and plant, nitrogen use efficiency and Pearson correlation. Most variables were influenced by N applications and the highest values were verified in the dose of 160 kg ha-1. The bean yield presented positive and significant correlation with most of the evaluated characteristics and was influenced by nitrogen addition in the system, being the best yield within the highest dose of nitrogen (3262 kg ha-1). Inoculation along with cobalt, molybdenum and 40 kg ha-1 of nitrogen increased yield in comparison with absence of N.
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- 2017
7. Atributos químicos do solo e produção de Urochloa brizantha cv. Marandu.
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Colmán Ribelatto, Patricia Juana, Marques Genú, Aline, Campos Lustosa, Sebastião Brasil, and André Pott, Cristiano
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MILK yield ,SOIL quality ,INDICATORS & test-papers ,SOIL sampling ,PASTURES ,NITROGEN fertilizers ,PHOSPHORUS ,MOLYBDENUM - Abstract
Copyright of Investigación Agraria is the property of Investigacion Agraria and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2019
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8. Alternatives in bean fertilization to reduce the application of N-urea
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Juliano Garcia Bertoldo, Amanda Pelisser, Raquel Paz da Silva, Rodrigo Favreto, and Luciene Antunes Dias de Oliveira
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Phaselous vulgaris L. ,nitrogen fertilizers ,seaweed extract ,molybdenum ,rock powder ,Agriculture (General) ,S1-972 - Abstract
As a result of the increasing use of chemical nitrogen fertilizers and their economic and environmental impacts, it is necessary to search for alternative methods to improve soil fertility, such as biological nitrogen fixation and/or alternative supplements of this nutrient. This study aimed at evaluating the effects of inoculation and application of seaweed extract, molybdenum and rock powder, as an alternative to the application of urea, in beans. A randomized blocks design, with three replications, was used. Two common bean cultivars (Pérola and FEPAGRO 26), as well as the following cultivation methods, were used: i) conventional; ii) inoculation with a mixture of three inoculants recommended for bean; iii) inoculation + complementation via seeds, with extracts of the Ascophyllum nodosum seaweed and mineral fertilizer containing rock powder and molybdenum; iv) inoculation + complementation via leaf, using products with extracts of the Ascophyllum nodosumseaweed and mineral fertilizer containing rock powder and molybdenum. The inoculation alone is not enough to reach grain yield levels similar to those reached using the conventional method. The cultivation method with inoculation + complementation via seeds maintains grain yield with the lowest cost, in relation to the conventional method.
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- 2015
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9. Síntese, caracterização e aplicação do trióxido de molibdênio na fotocatálise de efluente têxtil sintético.
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Silva, C. A. A., Silva, C. F., and Matos, J. M. E.
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SYNTHETIC textiles ,MOLYBDENUM ,PHOTOCATALYSIS ,LIGHT absorption ,BAND gaps - Abstract
Copyright of Ceramica is the property of Associacao Brasileira de Ceramica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2018
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- View/download PDF
10. Molybdenum in bunches quality of 'BRS Vitória' and 'Niagara Rosada' vines
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Camizotti, Karina Assis, Universidade Estadual Paulista (Unesp), and Tecchio, Marco Antonio
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Molybdenum ,Atividade antioxidante ,Descompaction grape bunches ,Uva sem semente ,Antioxidant activity ,Descompactação de cachos ,Compostos fenólicos ,Phenolic compound ,Vitis labrusca L ,Micronutriente ,Micronutrient ,Seedless grape - Abstract
Submitted by Karina Assis Camizotti (k.camizotti@unesp.br) on 2022-10-19T00:53:26Z No. of bitstreams: 1 DISSERTAÇÃO Completa - Karina.pdf: 1595632 bytes, checksum: 1ddea6efb26848b4e7ec28d9e2bc3b63 (MD5) Rejected by Messias Victor Telles de Carvalho (messias.victor@unesp.br), reason: Oi Karina, O seu trabalho apresenta alguns erros de formatação em relação ao manual de trabalhos acadêmicos da FCA. Entre em contato com Messias (messias.victor@unesp.br) para que ele verifique o seu material. Agradecemos a compreensão. on 2022-10-19T19:09:57Z (GMT) Submitted by Karina Assis Camizotti (k.camizotti@unesp.br) on 2022-10-25T11:14:25Z No. of bitstreams: 1 DISSERTAÇÃO Completa - Karina.pdf: 1615159 bytes, checksum: 1610ce6d11bda9382d9dd0687c1326e6 (MD5) Approved for entry into archive by Messias Victor Telles de Carvalho (messias.victor@unesp.br) on 2022-10-25T12:47:24Z (GMT) No. of bitstreams: 1 camizotti_ka_me_botfca.pdf: 1615159 bytes, checksum: 1610ce6d11bda9382d9dd0687c1326e6 (MD5) Made available in DSpace on 2022-10-25T12:47:24Z (GMT). No. of bitstreams: 1 camizotti_ka_me_botfca.pdf: 1615159 bytes, checksum: 1610ce6d11bda9382d9dd0687c1326e6 (MD5) Previous issue date: 2022-08-31 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Existe forte relação entre a aparência e aceitação dos cachos de uva pelo mercado consumidor, no qual há preferência por cachos grande, descompactados, com bagas grandes e coloração intensa. Dentro do setor vitícola, são realizadas diversas técnicas de manejo para aumentar não só tamanho dos cachos de uva, mas também suas características organolépticas e nutricionais. A pulverização de reguladores vegetais nos cachos de uva, são estratégias utilizadas durante décadas na viticultura, com a finalidade de descompactação e melhoria na qualidade dos frutos. No entanto, é uma prática com elevado custo devido ao valor dos produtos, havendo necessidade de validar produtos alternativos que vise a descompactação dos cachos com custo menor, sendo uma alternativa interessante o molibdênio. Dessa forma, esse estudo investigou o efeito na descompactação e melhoria da qualidade de cachos de videiras ‘BRS Vitória’ e ‘Niagara Rosada’, pela pulverização de doses de doses de molibdênio associadas a uma dose padrão de 30 mg.L-1 de GA3. O estudo foi conduzido durante os ciclos produtivos de 2020/2021 e 2021/2022, utilizando as doses de 0, 8, 16, 24 e 32 mg.L-1 de molibdênio pulverizadas em bagas de 6 a 8 mm de diâmetro. Os parâmetros avaliados foram: massa fresca de cachos, de bagas e de engaços; comprimento e largura de cachos, de bagas e de engaços; número de bagas por cacho; pH; teor de sólidos solúveis; acidez titulável; índice de maturação; teor de polifenóis, flavonoides e antocianinas; determinação da atividade antioxidante. As cultivares apresentaram resposta diferentes em relação aos produtos utilizados. Na primeira safra a ‘BRS Vitória’ apresentou respostas positivas na dose de 16 mg.L-1 de molibdênio com aumento na massa fresca de engaço e nos parâmetros físicas das bagas, o teor de antocianinas e atividade antioxidante tiveram melhores respostas com a dose de 32mg.L-1, enquanto que no segundo ciclo não houve resposta significativa entre os tratamentos. Para a cultivar Niagara Rosada a aplicação de 24 mg.L-1 de molibdênio foi a mais responsiva na descompactação dos cachos, enquanto o conteúdo de compostos fenólicos e atividade antioxidante obtiveram melhores respostas na dose de 7,83 mg.L-1. There is a strong relationship between the appearance and acceptance of grape bunches by the consumer market, in which there is a preference for large, uncompacted bunches, with large berries and intense coloring. Within the wine sector, several management techniques are carried out to increase not only the size of the grape bunches, but also their organoleptic and nutritional characteristics. The spraying of plant regulators on grape bunches are strategies used for decades in viticulture, with the purpose of unpacking and improving fruit quality. However, it is a practice with a high cost due to the value of the products, and there is a need to validate alternative products that aim to unpack the bunches at a lower cost, with molybdenum being an interesting alternative. Thus, this study investigated the effect on decompaction and improvement of bunch quality of 'BRS Vitória' and 'Niagara Rosada' vines, by spraying doses of molybdenum doses associated with a standard dose of 30 mg.L-1 of GA3 . The study was conducted during the production season of 2020/2021 and 2021/2022, using doses of 0, 8, 16, 24 and 32 mg.L-1 of molybdenum sprayed on berries of 6 to 8 mm in diameter. The parameters evaluated were: fresh mass of bunches, berries and stalks; length and width of bunches, berries and stalks; number of berries per bunch; pH; soluble solids content; titratable acidity; maturation index; content of polyphenols, flavonoids and anthocyanins; determination of antioxidant activity. The cultivars showed different responses in relation to the products used. In the first harvest, 'BRS Vitória' showed positive responses at the dose of 16 mg.L-1 of molybdenum with an increase in the fresh mass of stalk and in the physical parameters of the berries, the anthocyanin content and antioxidant activity had better responses with the dose of 32mg.L-1, while in the second season there was no significant response between treatments. For the cultivar Niagara Rosada, the application of 24 mg.L-1 of molybdenum was the most responsive in unpacking the bunches, while the content of phenolic compounds and antioxidant activity obtained better responses at the dose of 7.83 mg.L-1. 001 2020/12152-3
- Published
- 2022
11. Novel Ti-5Mo-Nb system alloys for biomedical applications
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Cardoso, Giovana Collombaro, Universidade Estadual Paulista (Unesp), and Grandini, Carlos Roberto [UNESP]
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Molibdênio ,Molybdenum ,Nióbio ,Niobium ,Ligas de titânio ,Módulo de elasticidade ,Titanium alloys ,Young’s modulus ,Biomaterial - Abstract
Submitted by Giovana Collombaro Cardoso (giovana.collombaro@unesp.br) on 2022-06-29T23:19:24Z No. of bitstreams: 1 dissertação_giovana_2022_0628.docx: 32199249 bytes, checksum: 3f822b17049b7f154068ace5b3ce27b2 (MD5) Rejected by Lucilene Cordeiro da Silva Messias null (lubiblio@bauru.unesp.br), reason: Favor refazer a submissão seguindo as orientações abaixo: 1 - O arquivo deve ser enviado em formado PDF. Agradecemos a compreensão. on 2022-06-30T12:29:30Z (GMT) Submitted by Giovana Collombaro Cardoso (giovana.collombaro@unesp.br) on 2022-06-30T12:55:25Z No. of bitstreams: 1 dissertação_giovana_2022_0628.pdf: 7131090 bytes, checksum: ffc73a2b90d091c5667fa45b8fe30e38 (MD5) Approved for entry into archive by Lucilene Cordeiro da Silva Messias null (lubiblio@bauru.unesp.br) on 2022-06-30T15:35:23Z (GMT) No. of bitstreams: 1 cardoso_gc_me_bauru.pdf: 7131090 bytes, checksum: ffc73a2b90d091c5667fa45b8fe30e38 (MD5) Made available in DSpace on 2022-06-30T15:35:23Z (GMT). No. of bitstreams: 1 cardoso_gc_me_bauru.pdf: 7131090 bytes, checksum: ffc73a2b90d091c5667fa45b8fe30e38 (MD5) Previous issue date: 2022-04-28 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) O titânio e suas ligas são amplamente utilizados em implantes cardiovasculares, odontológicos e ortopédicos devido ao excelente conjunto de propriedades que esses materiais possuem, como módulo de elasticidade mais baixo, alta resistência à corrosão e biocompatibilidade, comparados com outros biomateriais metálicos. A liga de titânio mais utilizada atualmente é a Ti-6Al-4V, porém problemas em relação à citotoxidade do vanádio e a associação da liberação de íons de alumínio no corpo com o desenvolvimento de desordens neurológicas, vem incentivando o desenvolvimento de novas ligas com outros elementos que melhorem ainda mais as boas propriedades do titânio e que não sejam prejudiciais ao organismo, como o molibdênio e o nióbio. Assim, nesse trabalho, novas ligas do sistema Ti-5Mo-xNb (x = 0, 10, 20 e 30 %p) foram desenvolvidas e caracterizadas química, estrutural, microestrutural e mecanicamente. Os lingotes foram fundidos em um forno a arco-voltaico, com atmosfera inerte de argônio. Após a fusão, as amostras foram tratadas termicamente para garantir a homogeneização dos elementos de liga, laminadas a quente e recozidas. A análise química envolveu medidas de densidade, composição química semiquantitativa por Espectroscopia por Dispersão de Energia de Raios X (EDS) e mapeamento químico. A estrutura e microestrutura das amostras foram analisadas por difração de raios X, com refinamento pelo método de Rietveld, e com imagens de microscopia óptica e eletrônica de varredura. Ensaios de módulo de elasticidade dinâmico e microdureza foram efetuados para a caracterização mecânica e testes de viabilidade e adesão celular avaliaram a citotoxidade in vitro das ligas produzidas. Os resultados mostraram que a adição de nióbio promoveu aumento da fase β do titânio. A quantidade dos elementos substitucionais e os diferentes tratamentos termomecânicos influenciaram na microestrutura e propriedades mecânicas das ligas. A liga Ti-5Mo-30Nb mostrou melhor potencial para futuras aplicações biomédicas. Titanium and its alloys are widely used in cardiovascular, dental, and orthopedic implants due to their excellent properties, such as lower elastic modulus, high corrosion resistance, and biocompatibility, compared to other metallic biomaterials. The most used titanium alloy today is Ti-6Al-4V. However, problems related to the cytotoxicity of vanadium and the association of the release of aluminum ions in the body with the development of neurological disorders have encouraged the development of new alloys with other elements that further improve the good properties of titanium and that are not harmful to the body, such as molybdenum and niobium. Thus, in this work, new alloys of the Ti-5Mo-xNb system (x = 0, 10, 20, and 30 wt%) were developed and characterized chemically, structurally, microstructurally, and mechanically. The ingots were arc melted in argon gas atmosphere. After melting, the samples were heat-treated to ensure homogenization of the alloying elements, hot rolled, and annealed. The chemical analysis involved density measurements, semi-quantitative chemical composition by energy-dispersive X-ray spectrometry (EDS), and chemical mapping. The structure and microstructure of the samples were analyzed by X-ray diffraction, with refinement by the Rietveld method, and with optical and scanning electron microscopy images. Young's modulus and microhardness tests were performed for mechanical characterization, and cell viability and adhesion tests evaluated the in vitro cytotoxicity of the produced alloys. The results showed that the addition of niobium promoted an increase in the β phase of titanium. The amount of substitutional elements and the different thermomechanical treatments influenced the microstructure and mechanical properties of the alloys. Ti-5Mo-30Nb alloy showed better potential for future biomedical applications. CAPES Finance Code 001
- Published
- 2022
12. Viabilidade do inoculante turfoso produzido com bactérias associativas e molibdênio Viability of peat inoculum produced with associative bacteria and molybdenum
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Salomão Lima Guimarães, Vera Lúcia Divan Baldani, and Jorge Jacob-Neto
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Bactérias ,Inoculação ,Molibdênio ,Bacteria ,Inoculation ,Molybdenum ,Agriculture (General) ,S1-972 - Abstract
Dentre os veículos de inoculação de bactérias diazotróficas, o turfoso é considerado o mais utilizado no Brasil. A turfa possibilita a viabilidade de um grande número de células, protegendo-as também das adversidades do solo. O objetivo deste trabalho foi avaliar a viabilidade do inoculante turfoso desenvolvido com bactérias diazotróficas associativas e molibdênio. As bactérias BR11417 (Herbaspirillum seropedicae) e BR11340 (Burkholderia sp.), foram multiplicadas por um período de 24 horas e uma alíquota de 10 mL com 10(8) cel. mL-1 foi transferida para sacos de polipropileno contendo 35 g de turfa. Foram adicionadas duas doses e duas fontes de molibdênio: 1,12 e 2,25 g de molibdato de sódio e de amônio, respectivamente. Como controle, foi utilizado o inoculante sem molibdênio. A legislação brasileira, por meio da lei n° 86955, especifica que os inoculantes comerciais à base de micro-organismos fixadores de nitrogênio apresentem concentrações mínimas de 10(8) células viáveis por grama do produto no momento do uso e que a viabilidade das células seja mantida por um período mínimo de seis meses. Este estudo mostrou que sem a adição do molibdênio ao inoculante, as bactérias sobreviveram com um número de células viáveis em torno de 10(8) células g-1 de inoculante, por um período de até 110 dias. Com a adição do molibdênio, o inoculante manteve-se viável por um período de 180 dias. A aplicação do molibdênio contribui para o aumento da viabilidade do inoculante turfoso produzido com as estirpes BR11417 e BR11340.Among the vehicles in use for diazotroph inoculation, peat is considered the most-widely used in Brazil. Peat makes possible the viability of a large number of cells, at the same time protecting them from adversities found in the soil. The objective of this study was to evaluate the viability of peat inoculum developed with diazotroph bacteria and molybdenum. The bacteria BR11417 (Herbaspirillum seropedicae) and BR11340 (Burkholderia sp.) were allowed to multiply for a period of 24 hours, and a sample of 10 ml with 10(8) cel. mL-1 was transferred to polypropylene bags containing 35 g of peat. Two dosages and two sources of molybdenum were then added: 1.12 and 2.25 g of sodium molybdate and ammonium molybdate respectively. Inoculum with no molybdenum was used as control. With law No. 86955, Brazilian legislation specifies that commercial inoculants based on nitrogen-fixing microorganisms have minimum concentrations of 10(8) viable cells per gram of product at the time of use, and that viability of the cells be maintained for a period of at least six months. This study showed that without the addition of molybdenum to the inoculum, bacteria survived with a viable-cell total of about 10(8) cells g-1 of inoculum for a period of up to 110 days. With the addition of molybdenum, the inoculum remained viable for a period of 180 days. The application of molybdenum contributes to the increased viability of peat inoculum produced with the bacterial strains BR11417 and BR11340.
- Published
- 2013
- Full Text
- View/download PDF
13. Aplicação foliar de molibdênio durante a maturação de sementes de soja Leaf application of molybdenum during soybean seed maturation
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Gustavo Lima Milani, João Almir Oliveira, Elise de Matos Pereira, Bruno Oliveira Carvalho, Gustavo Evagelista Oliveira, and Ricardo Resende Costa
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Glycine max ,molibdênio ,produtividade ,qualidade fisiológica ,molybdenum ,yield ,physiological quality ,Agriculture (General) ,S1-972 - Abstract
A aplicação foliar, objetivando o acúmulo do nutriente na semente, é uma tecnologia recente e, por isso, pouco se sabe sobre o seu efeito na qualidade fisiológica e a influência da sua aplicação sobre a produtividade das plantas. Neste Trabalho objetivou-se avaliar a produtividade das plantas que receberam a aplicação de Mo via foliar em diferentes doses, e a qualidade fisiológica das sementes provenientes dessas plantas. A fonte de molibdênio usada foi o molibdato de sódio (39% Mo). As sementes receberam o Mo por meio de aplicações foliares durante o processo de maturação, em aplicação única e parcelada em duas vezes, feitas entre os estágios R5.2 e R5.4, em dois ensaios, em Lavras e Ituiutaba, MG. Os tratamentos para os dois ensaios foram: aplicação de 1000g, de 800g, 600g, de 400g, 2 aplicações de 500g, de 400g, de 300g, de 200g por hectare e 0g (testemunha). Os ensaios foram instalados em DBC, com quatro repetições. Avaliou-se o teor de Mo na semente, a produtividade das plantas que receberam a aplicação foliar e a qualidade fisiológica nos testes de germinação, IVE, teste de frio e condutividade elétrica. O teor de Mo nas sementes de soja é crescente com a dose aplicada nas plantas e independe da aplicação em dose única ou parcelada. O acúmulo de Mo nas sementes não interfere na produtividade e na qualidade fisiológica das sementes soja.Leaf application with the objective of accumulating this nutrient in the seed is a new technology so its effects on the physiological quality and influence in the yield of the plants are little known. The objective of this study was to evaluate the yield of the plants that underwent leaf application of Mo at different rates, and the physiological quality of soybean seeds resulting from those plants. The source of molybdenum used was sodium molybdate (39% Mo). The seeds received Mo through leaf applications during the maturation process, in one application divided twice, made between R5.2 and R5.4 stages, in two tests, in Lavras and Ituiutaba, MG. The treatments of the two assays were: application of 1000g; of 800g; of 600g; of 400g; two applications of 500g; 400g; 300g; 200g per ha and 0g (control). The tests were made in DBC, with four replicates. Mo content in seed, yield of the plants that received the leaf application and the physiological quality the tests of germination, EVI, cold test and conductivity electrical were evaluated. The content of Mo in the seed is directly proportional to the quantity applied to the plants regardless of there being only one application or divided. The accumulation of Mo in the seeds does not affect the yield and the physiological quality of soybean seeds.
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- 2010
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14. Branqueamento de polpa celulósica kraft de eucalipto com peróxido ácido ativado por molibdênio Kraft pulp bleaching with molybdenum activated acid peroxide (P Mo stage)
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Marcos Sousa Rabelo, Vanessa Lopes Silva, Denise Pires de Barros, Jorge Luiz Colodette, Vera Maria Sacon, and Marcelo Rodrigues da Silva
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hydrogen peroxide ,molybdenum ,pulp bleaching ,Chemistry ,QD1-999 - Abstract
Optimum conditions to run the P Mo stage for bleaching eucalyptus kraft pulp were 90 ºC, pH 3.5, 2 h, 0.1 kg/t Mo and 5 kg/t H2O2. The P Mo stage efficiency increased with decreasing pH (1.5-5.5) and increasing temperature (75-90 ºC), time (2-4 h), and hydrogen peroxide (3-10 kg/t) and molybdenum concentration (0.1-0.4 kg/t). The implementation of the P Mo stage, as replacement for the A stage, decreased total active chlorine demand of the OAZDP sequence by 6 kg/t to reach 90% ISO, both in laboratory and mill scale. Such practice resulted in decreased bleaching chemical costs to produce fully bleached pulp of 90% ISO.
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- 2009
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15. Inoculação das sementes e adubações nitrogenada e molíbdica do feijoeiro-comum, em Rolim de Moura, RO Seeds inoculation and nitrogen and molybdenum fertilization of common bean in Rolim de Moura, RO
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Franciele Caroline de Assis Valadão, Adriano Jakelaitis, Lenita Aparecida Conus, Lucas Borchartt, Abdias Alves de Oliveira, and Daniel Dias Valadão Junior
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Phaseolus vulgaris ,Rhizobium tropici ,fixação biológica de nitrogênio ,molibdênio ,biological nitrogen fixation ,molybdenum ,Science (General) ,Q1-390 - Abstract
O objetivo deste estudo foi avaliar o desempenho do feijoeiro-comum (Phaseolus vulgaris L) em função da inoculação de sementes com Rhizobium tropici e das adubações nitrogenada e molibdica. Utilizou-se o delineamento em blocos casualizados, com quatro repetições, em arranjo fatorial 2x2x2, constituindo-se das combinações de ausência e presença de inoculação de sementes, da adubação molíbdica e da adubação nitrogenada. A inoculação das sementes foi imediatamente antes da semeadura com inoculante turfoso composto da estirpe CIAT 899 (SEMIA 4077); a adubação nitrogenada foi na semeadura (10 kg.ha-1) e em cobertura (50 kg.ha-1), quando as plantas apresentaram a terceira folha trifoliolada expandida e o molibdênio (Mo) foi aplicado em pulverização foliar na dose de 60 g.ha-1. Não foram observados efeitos dos tratamentos para a massa seca de raízes e o número de vagens por planta. A adubação nitrogenada reduziu a nodulação nos feijoeiros. Todavia, com a adubação nitrogenada foi verificado incremento na altura e na massa seca da parte aérea dos feijoeiros. Grãos de feijão mais pesados foram observados em feijoeiros adubados com N na ausência de Mo. As interações entre adubação nitrogenada e molibdica com inoculação de sementes afetaram, também, o teor de N foliar e o número de grãos por vagem A inoculação de sementes proporcionou nos feijoeiros rendimentos de grãos semelhantes aos fertilizados com N.The aim of this study was to evaluate the effects of seed inoculation with Rhizobium tropici and nitrogen and molybdenum fertilization on the performance of the common-bean (Phaseolus vulgaris L.). A complete randomized block design with four replicates was used, in a factorial arrangement 2x2x2, with the combinations of absence and presence of seed inoculation and nitrogen (N) and molybdenum (Mo) fertilization. Seeds inoculation was just before sowing with a peat inoculante composed by the strain CIAT 899 (SEMIA 4077), N was provided at sowing (10 kg.ha-1) and coverage (50 kg.ha-1) when the plants showed the third trifoliate sheet expand and Mo was applied by foliar spraying with 60 g.ha-1 when plants were at beginning of flowering . No effect of treatments on the dry mass of roots and the number of pods per plant was observed. N fertilization reduced nodulation of plants, however, N fertilization lead to an increase in height and dry mass of bean shoots. It was also observed that plants fertilized with N but in the absence of Mo shoed heavier grains. The interactions between N and Mo fertilization with inoculation of seed negatively affected the leaf N content and the number of grains per pod. The inoculation of seed in beans provided grain yields similar to those provided by the treatment with N fertilization.
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- 2009
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16. Misturas de herbicidas com adubo molíbdico na cultura do feijão Mixtures of herbicides and molybdic fertilizer in beans
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G.A.A. Araújo, A.A. Silva, A. Thomas, and P.R.R. Rocha
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controle químico ,molibdênio ,mistura em tanque ,plantas daninhas ,chemical control ,molybdenum ,tank mixture ,weeds ,Biology (General) ,QH301-705.5 ,Botany ,QK1-989 - Abstract
Foram conduzidos dois experimentos em Coimbra-MG no período de março a julho, em anos consecutivos, com o objetivo de avaliar possível interação proporcionada pela mistura de adubo molíbdico com herbicidas em relação à produtividade e ao controle de plantas daninhas na cultura do feijão, cv. Meia Noite. O delineamento experimental foi o de blocos ao acaso, com quatro repetições, tendo as parcelas subdivididas. As parcelas foram representadas pela ausência e presença de capina, e as subparcelas, pelos tratamentos com os herbicidas metolachlor, fomesafen, bentazon, imazamox e fluazifop-p-butil + fomesafen e pela testemunha com capina, associados ou não ao molibdênio. Este micronutriente foi aplicado na dosagem de 80 g ha-1, aos 23 dias após a emergência da cultura, em mistura no tanque com os herbicidas aplicados em pós-emergência e isoladamente, quando o herbicida foi aplicado apenas em pré-emergência e nas testemunhas. Utilizou-se como fonte de molibdênio o molibdato de amônio. O molibdênio pode ser misturado aos herbicidas estudados e, mesmo assim, proporcionar aumento na produtividade; os herbicidas metolachlor + fomesafen, metolachlor + bentazon, fluazifop-p-butil + fomesafen e imazamox apresentaram de muito bom a ótimo controle de Ipomoea grandifolia, Brachiaria plantaginea e Acanthospermum hispidum. Não houve redução no controle das espécies daninhas presentes em ambos os experimentos quando o molibdênio foi misturado à calda.Two experiments were carried out in Coimbra MG, during consecutive years from March to July, aiming to evaluate the possible interaction provided by the mixture of molybdic fertilizer and herbicides in relation to productivity and weed control in bean crop, cv. 'Meia Noite' a split-plot randomized block experimental design was used with four replicates The plots were represented by the absence and presence of weeding. The split plots were represented by the treatments with the herbicides metolachlor, fomesafen, bentazon, imazamox and fluazifop-p-butyl + fomesafen, as well as the non-weeded control weeded controls associated or not to molybdenum. At 23 days after bean crop emergence, molybdenum was applied at the dosage of 80 g ha¹ in all treatments. In plots on which the herbicides were applied at post-emergence, molybdenum was applied in a mixture made in a sprayer tank with herbicides and in plots on which the herbicide was applied at pre-emergence. In those receiving no herbicide, molybdenum was separately applied. Ammonium molybdate was used as a molybdenum source. The following observations were made: molybdenum may be mixed with the studied herbicides; even when mixed, molybdenum increases productivity; the herbicides metolachlor + bentazon, fluazifop-p-butyl + fomesafen and imazamox showed a very good to excellent control against Ipomoea grandifolia, Brachiaria plantaginea and Acanthospermum hispidum. No reduction was observed in controlling all the weed species present in both experiments, when molybdenum was mixed to the syrup.
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- 2008
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17. Composição química e do conteúdo de energia do cariru (Talinum esculentum, Jacq.) Chemical composition and energy content of cariru (Talinum esculentum, Jacq.)
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Luciana R. Trajano Manhães, Mônica de Moraes Marques, and Armando Ubirajara O. Sabaa-Srur
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Talinum esculentum ,Jacq. ,Zinco ,Ferro ,Manganês ,Selênio ,Iron ,Zinc ,Molybdenum ,Manganese ,Selenium ,Science (General) ,Q1-390 - Abstract
Estudos recentes têm relatado o estado pluricarencial da população dos estados da Região Norte do Brasil. Paradoxalmente nessa região encontra-se uma grande biodiversidade da flora com variadas frutas e hortaliças, ainda não tão conhecidas, mas que os pesquisadores acreditam ser altamente nutritivas. Entre elas, tem-se o cariru, planta herbácea da família Portulacea, hortaliça própria da região amazônica e de fácil cultivo. Amostras dessa verdura foram submetidas a determinações analíticas a fim de obter maiores informações sobre seu valor nutricional. A maior fração desse vegetal é a água (92,24%), seguida de lipídeos (3,04%), carboidratos (2,94%), minerais totais (1,71%) e de proteína (0,07%), constituindo um alimento de reduzido valor calórico (40 Kcal/100g). Tendo em vista os resultados encontrados na análise de minerais, essa folhosa pode ser considerada como excelente fonte de ferro, zinco e molibdênio, já que o consumo de 200 g/dia desse alimento atenderia as necessidades diárias desses nutrientes. Chama-se atenção para os conteúdos de selênio e manganês, onde 100g dessa biomassa fresca podem fornecer duas e três vezes, respectivamente, as quantidades recomendadas para adultos pelos órgãos internacionais de saúde, com as devidas precauções, já que excessos desses oligominerais podem causar danos à saúde. Sendo assim, recomenda-se a inclusão dessa folhosa no hábito alimentar brasileiro, por apresentar minerais em quantidades suficientes para minimizar o estado carencial de muitas pessoas, residentes na região Norte do país, exatamente onde é encontrada em abundância e com custo reduzido.Recent studies have been related a food lacking state of population in states from north of Brazil. Paradoxically in this region a great biodiversity in the flora can be found with various fruits and vegetables, not very known so far, but researchers believe in their high nutritional values. One of them is Cariru, an herbaceous plant to Portulacea family, vegetable native from Amazon region and easy to grow. Sample of this vegetable was transformed in biomass and submitted to a quantitative analysis in order to have a lot of information about nutritional value. Analysis showed that the biggest amount was moisture (92.44%), followed by lipids (3.04%), carbohydrates (2.94%), total minerals (1.71%) and protein (0.07%), compound a reduced caloric food, 40 kcal/100g. Analyzing the mineral results, cariru can be consider as an excellent iron, zinc and molybdenum source, that the consumption of 200 gin the vegetable/day would attend daily needs of these nutrients. This is very important to selenium and manganese contents, because 100g fresh of biomass can supply 2 or 3 times, respectively, the RDI for adult. The excess of this oligominerals can be hazardous for human body. Therefore, the inclusion of this vegetable on a diet of Brazilian is recommended, because it presents enough minerals to minimize the food lacking state of people who lives in North of Brazil.
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- 2008
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18. Estudio de las propiedades del hierro fundido gris con niobio añadido para trabajos en caliente
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Meira, Marcos Paulo, Lima, Euclides Antônio Pereira de, and Nascimento , Francisco Manoel Perez do
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Disco de freno ,Molibdênio ,Molybdenum ,Fundición gris ,Nióbio ,Molibdeno ,Ferro fundido cinzento ,Gray cast iron ,Niobium ,Disco de freio ,Break discs - Abstract
One of the main materials used in the production of automobile parts is gray cast iron. This material is widely used in the production of brake discs. The aim of this study was to evaluate the mechanical and physical behavior of four pearlitic gray cast iron alloys. For this purpose, four alloys named: base alloy, base alloy + 0.10% Nb, base alloy + 0.20% Nb and base alloy + 0.15% Mo, were cast and subsequently evaluated for: chemical composition, tensile strength at temperatures of 22°C, 380°C, 480°C, 580°C and 680°C, hardness, microstructure and thermal diffusivity. In tensile strength tests at temperatures from 22°C to 680°C, it was observed that when added to the base alloy, the elements niobium and molybdenum increase the strength limit of gray cast iron, as they form carbides and promote the refining of perlite. The addition of Nb or Mo also increased the hardness of the alloys in relation to the base alloy. Regarding the microstructure, it was also possible to observe that the alloys with the addition of Nb or Mo had slightly more refined graphite. Diffusivity tests showed that the base cast iron + 0.10% Nb has better diffusivity results at all tested temperatures (380°C, 480°C, 580°C, and 680°C). This fact may be associated with the increased amount of graphite and the addition of 0.10% niobium content. Uno de los principales materiales en la fabricación de piezas de automóvil es el hierro fundido gris, material utilizado en la fabricación de discos de freno. El propósito de este estudio fue evaluar el comportamiento mecánico y físico de cuatro aleaciones de hierro fundido gris perlítico. Para ello, se moldearon cuatro aleaciones denominadas aleación base, aleación base + 0,10% Nb, aleación base + 0,20% Nb y aleación base + 0,15% Mo, y posteriormente se evaluaron para: composición química, resistencia a la tracción a temperaturas de 22°C, 380°C, 480°C, 580°C y 680°C, dureza, microestructura y difusividad térmica. En ensayos de resistencia a la tracción a temperaturas de 22 ° C a 680 ° C, se observó que al agregarse a la aleación base, los elementos niobio o molibdeno aumentan la dureza de la fundición gris, ya que son fuertes formadores de carburos de alta dureza y promueven el refinamiento de la perlita. En cuanto a la microestructura, se pudo observar que la matriz metálica es muy similar para todas las aleaciones, con tendencia a disminuir el tamaño del grafito cuando se agregan los elementos niobio o molibdeno. Através de las pruebas de difusividad se pudo observar que la aleación denominada aleación base + 0,10% Nb presenta un mejor resultado de difusividad a todas las temperaturas probadas (380°C, 480°C, 580°C y 680°C). Este hecho se puede atribuir a la mayor cantidad de grafito y la adición de niobio en el contenido de 0,10%. Um dos principais materiais utilizados na fabricação de peças automobilísticas é o ferro fundido cinzento. Este material é amplamente utilizado na fabricação de discos de freios. A proposta deste estudo foi avaliar o comportamento mecânico e físico de quatro ligas de ferro fundido cinzento de matriz perlítica. Para tanto, quatro ligas denominadas: liga base, liga base + 0,10% Nb, liga base + 0,20% Nb e liga base + 0,15% Mo, foram fundidas e posteriormente avaliadas quanto à: composição química, resistência à tração nas temperaturas de 22°C, 380°C, 480°C, 580°C e 680°C, dureza, microestrutura e difusividade térmica. Nos ensaios de resistência à tração nas temperaturas de 22°C a 680°C, pôde-se observar que quando adicionados na liga base, os elementos nióbio e molibdênio elevam o limite de resistência do ferro fundido cinzento, pois são formadores de carbonetos e promovem o refino da perlita. A adição de Nb ou Mo elevou também a dureza das ligas em relação à liga base. Com relação à microestrutura, foi possível observar também que as ligas com adição de Nb ou Mo apresentaram grafita levemente mais refinada que a liga base. Através dos ensaios de difusividade, pôde-se observar que a liga denominada liga base + 0,10% Nb apresenta um resultado melhor de difusividade em todas as temperaturas testadas (380°C, 480°C, 580°C e 680°C). Este fato pode ser atribuído à maior quantidade de grafita e à adição de nióbio no teor de 0,10%.
- Published
- 2021
19. INFLUÊNCIA DO MOLIBDÊNIO ASSOCIADO AO COBALTO NA CULTURA DA SOJA, APLICADOS EM DIFERENTES ESTÁGIOS FENOLÓGICOS
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Carlos Sérgio TIRITAN, José Salvador Simoneti FOLONI, Agnaldo Massao SATO, Cévio Alberto MENGARDA, and Diego Henriques SANTOS
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Cobalt ,Molybdenum ,Soybeans ,Agriculture ,Agriculture (General) ,S1-972 - Abstract
With the objective of indicating the influences of the molybdenum associated to the cobalt in the manuring of the soy with applications in different fenologics phases, took place an experiment in portions subdivided with four repetitions. The data were submitted to the variance analysis and test Tukey. They happened significant differences of the control for the other treatments in the productivity, showing answers to the manuring of the micronutrients. In relation to the nutrients in the grains, nitrogen, match and magnesium didn't present significant differences, the potassium already presented higher tenor in the control. For the calcium a significant difference was observed among the application through seed and the application in the seed and to the 40 days of the other applications. The sulfur presented differences of the control for the other treatments. Like this, the presented results indicated that the addition of cobalt and molybdenum in the manuring of the soy, through seed, is viable and it guarantees won of productivity.
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- 2007
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20. PRODUÇÃO DE MOLIBDÊNIO METÁLICO A PARTIR DA MOLIBDENITA DE CARNAÍBA (BAHIA).
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DE SOUZA, A. C. S. and DE ANDRADE LIMA, L. R. P.
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Brazil has no official reserves of molybdenum, so the artesanal production of molybdenite from the astesanal mine of Carnaíba (Bahia) is an alternative to the domestic market demand. In this work the molybdenite from Carnaíba was used to produce molybdenum using roasting, leaching with NH4OH, precipitation and thermal degradation and reduction using hydrogen. The molybdenite crystals have 38% of molybdenum and approximately 10% micas. The Mo extraction by leaching was close to 90%. The molybdenum oxide produced has good crystallinity. The molybdenum produced by reduction was a powder with 99% of Mo. The overall process recovery was 85%. [ABSTRACT FROM AUTHOR]
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- 2016
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21. INFLUÊNCIA DO SISTEMA DE CULTIVO NAS CARACTERÍSTICAS PRODUTIVAS DO FEIJÃO XODÓ (phaseolus vulgaris L).
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Sá Vasconcelos Júnior, José Francisco, Ferreira Garcia, Ricardo, Souza Rabello, Wanderson, Pereira Correa Klaver, Pablo, and Coimbra Manhães, Carmen Maria
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This study aimed to compare two cropping systems for common beans. The experimental design was completely randomized with twelve repetitions. The variety used was the BR1 Xodó. The experiment was conducted in an area 50 x 60 m, which is divided into two areas of 27 x 47 m, and each with a cultivation system. In each area, were demarcated and georeferenced twelve installments of 15 mx 6 m, 1 m separating the plots, representing 12 repetitions per area. In system 1 there was no irrigation and weed control was carried out by weeding. The system 2 was irrigated, fertilized and weed control done by herbicides. Furthermore, it was held subsoil and application of molybdenum. The adoption of cropping system 2 increased by 81.15% productivity Xodó beans. [ABSTRACT FROM AUTHOR]
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- 2016
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22. INTERAÇÃO ENTRE MOLIBDÊNIO E NITROGÊNIO NO CRESCIMENTO DE BRACHIARIA BRIZANTHA CV. MARANDU
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Danilo Zanutto de Oliveira Medeiros and Gustavo Maia Souza
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Brachiaria brizantha ,Growth ,Molybdenum ,Nitrate reductase ,Nitrogen ,Agriculture ,Agriculture (General) ,S1-972 - Abstract
Because of depletion of the soils in south-east Brazil, Brachiaria sp. has increased its importance among cattle farmers, since it can tolerate soils with low nutrient levels. The hypothesis of this study took into account that, since Mo is a co-factor of nitrate reductase activity affecting nitrogen metabolism, different concentrations of this micronutrient could support an increase in B. brizanthagrowth. Therefore, the objective of this study was to verify the effects of different concentrations of Mo on physiology and yield of Brachiaria brizantha cv. 'Marandu', and the interaction with different N concentrations in Presidente Prudente – SP, Brazil. Under simulated graze in greenhouse conditions, percentage of total protein, dry matter production, number of shoots, and nitrate reductase activity was evaluated. Our results didn’t show any expected dose-response curve in relation to Mo concentrations. However, the results indicated that Mo supplies for B.brizantha should be carried out plus nitrogen supplementation.
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- 2005
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23. TEORES DE VANáDIO, MOLIBDêNIO E ANTIMôNIO EM SOLOS DE DIFERENTES LITOLOGIAS EM SANTA CATARINA
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Matheus Rodrigo Machado, David José Miquelluti, Mari Lucia Campos, and Ilana Marin Suppi
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Total organic carbon ,Trace element ,Vanadium ,chemistry.chemical_element ,trace elements ,Chemistry ,chemistry ,Antimony ,Molybdenum ,Environmental chemistry ,Soil water ,Cation-exchange capacity ,source material ,Inductively coupled plasma ,QD1-999 ,natural contents - Abstract
VANADIUM, MOLYBDENUM AND ANTIMONY CONTENTS IN SOILS OF DIFFERENT LITHOLOGIES IN SANTA CATARINA. Trace element levels knowledge in soils is important for establishing quality standards. This study has objective to determine levels of vanadium (V), molybdenum (Mo) and antimony (Sb) in soils from Santa Catarina, observing the different source materials and establishing relationships between these elements and soil properties. The extractions occurred according to USEPA 3051 A protocol, with nitric and hydrochloric acid addition for V and Mo and only with hydrochloric acid for Sb. The quantification of V and Mo occurred by inductively coupled plasma optical emission spectrometry and of Sb by hydride generation inductively coupled plasma optical emission spectrometry. The results were submitted to variance analysis and Scott-Knott test and evaluated by Pearson’s correlation with soil attributes. V and Mo contents differed between soils of different source materials. Highest V levels were found in andesite and basalt soils and Mo in porphyry phonolite, granite, mica schist and sedimentary rocks. V and Sb showed a positive correlation with each other and with oxides of iron, silt, and organic carbon. Mo showed a negative correlation with cation exchange capacity (CEC), iron oxides and organic carbon
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- 2021
24. Nitrate reductase activity in leaves and stems of tanner grass (Brachiaria radicans Napper)
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Jairo Osvaldo Cazetta and Luciana Cristine Vasques Villela
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Brachiaria arrecta ,nitrogen ,molybdenum ,enzyme ,Agriculture (General) ,S1-972 - Abstract
Tanner grass (Brachiaria radicans Napper) is a forage plant that is adapted to well-drained soils or wetlands, and responds well to nitrogen (N) fertilization. The assimilation of N involves the nitrate reductase (NR) enzyme, and its activity seems to be dependent on N supply. Molybdenum (Mo) is also important because it is a cofactor of NR. In this study, the variables of an in vivo assay were optimized for measuring nitrate reductase activity (NRA) in the leaves and stem tissues. This method was used to evaluate NO3- metabolism in plants fertilized with NaNO3, NH4Cl or urea, in association with or without application of H2MoO4, aiming to provide guidelines for N management of this species. The best conditions to determine NRA involved the incubation of 300 mg of tissues in a medium composed of 200 mmol dm3 phosphate buffer (pH 7.4), 60 mmol dm3 KNO3, 10 cm³ dm3 n-butanol, 0.1 cm³ dm3 detergent (triton-X-100®), under vacuum and in the dark for a period of 60 to 100 minutes. Leaves showed NRA levels two to three times higher than stems. Although there were some interactions between treatments, stem fresh weight and NRA were not affected by N sources. Plants fertilized with NaNO3 showed the best growth and NRA values when compared with NH4Cl and urea, which had, respectively, the lowest and intermediate scores. The application of Mo in the absence of N improved NRA and did not affect leaf and stalk growth. In the presence of N, the Mo levels applied limited leaf NRA and plant development.
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- 2004
25. Rendimento de grãos, componentes do rendimento e índice SPAD do feijoeiro (Phaseolus vulgaris L.) em função de época de aplicação e do parcelamento da aplicação foliar de molibdênio Grain yield, yield components and bean SPAD index of common bean (Phaseolus vulgaris L.) in relation to time and partitioning of molybdenum foliar spray
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André Assis Pires, Geraldo Antônio de Andrade Araújo, Glauco Vieira Miranda, Paulo Geraldo Berger, Alexandre Cunha de Barcellos Ferreira, Poliana Daré Zampirolli, and Uberlando Tiburtino Leite
- Subjects
Aplicação foliar ,parcelamento ,molibdênio ,feijoeiro ,Phaseolus vulgaris ,Application foliar ,portioning ,molybdenum ,common bean ,Agriculture (General) ,S1-972 - Abstract
Objetivando avaliar a influência da época de aplicação e do parcelamento da dose de molibdênio, aplicado via foliar sobre os componentes da produção e índice SPAD do feijoeiro (Phaseolus vulgaris L.), variedade Meia Noite, conduziram-se dois experimentos em área da Universidade Federal de Viçosa, no município de Coimbra, MG, semeados em março e julho de 2002. O delineamento experimental foi o de blocos casualizados, com dez tratamentos e quatro repetições. Os tratamentos avaliados foram: 1- testemunha, sem Mo; 2- 80 g ha-1 de Mo aplicados 15 dias após a emergência (DAE); 3- 40 g ha-1 de Mo aplicados 15 DAE e 40 g ha-1 20 DAE; 4- 40 g ha-1 de Mo 15 DAE e 40 g ha-1 25 DAE; 5- 40 gha-1 de Mo 15 DAE e 40 g ha-1 30 DAE; 6- 80 gha-1 de Mo 20 DAE; 7- 40 g ha-1 de Mo 20 DAE e 40 g ha-1 25 DAE; 8- 40 g ha-1 de Mo 20 DAE e 40 gha-1 30 DAE; 9- 80 g ha-1 de Mo 25 DAE; 10- 40 g ha-1 de Mo 25 DAE e 40 g ha-1 30 DAE. Os dados dos dois experimentos foram submetidos a uma análise conjunta. A adubação foliar molíbdica aumenta a produtividade e o índice SPAD no cultivo de verão-outono com início aos 15 e 20 DAE, mas não aos 25 DAE. O parcelamento da dose não aumenta a produtividade. No cultivo de inverno-primavera, os tratamentos com molibdênio aumentam a produtividade.A field trial was undertaken to evaluate the effect of the foliar application and dose partitioning of molybdenum on yield components and SPAD index of common bean (Phaseolus vulgaris L.), var. Meia Noite, sowed in March and in July of 2002, in an area of the Universidade Federal de Viçosa, Coimbra, MG. The randomized block experimental design was used with ten treatments and four replicates: The appraised treatments were: 1 control, without Mo; 2 - 80 g ha-1 Mo applied at 15 days after emergency (DAE); 3 - 40 g ha-1 Mo applied at 15 DAE, and 40g at 20 DAE; 4 - 40 g ha-1 Mo applied at 15 DAE, and 40 g ha-1 Mo at 25 DAE; 5 - 40 g ha-1 Mo applied at 15 DAE, and 40 g ha-1 Mo at 30 DAE; 6 - 80 g ha-1 Mo applied at 20 DAE; 7 - 40 g ha-1 Mo applied at 20 DAE, and 40 g ha-1 Mo at 25 DAE; 8 - 40 g ha-1 Mo applied at 20 DAE, and 40 g ha-1 Mo at 30 DAE; 9 80 g ha-1 Mo applied at 25 DAE; 10 - 40 g ha-1 Mo applied at 25 DAE, and 40 g ha-1 Mo at 30 DAE. ). Data of two trials were submitted to combined analysis. Molybdenum foliar spray increased yield and SPAD index in summer-autumn cultivation when started 15 or 20 DAE, but not 25 DAE. Dose partitioning had no effect on yield increase yield. In winter-spring cultivation, all molybdenum treatments increased yield.
- Published
- 2004
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26. QUALIDADE FISIOLÓGICA DE SEMENTES DE CRAMBE TRATADAS COM ZINCO E MOLIBDÊNIO
- Author
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Josiane Cantuária Figueiredo, Marina Borges de Oliveira Silva, Miquéias de Oliveira Assis, Lucas Vinícius de Souza Cangussú, Andréia Márcia Santos de Souza David, and Hugo Tiago Ribeiro Amaro
- Subjects
biology ,lcsh:S ,food and beverages ,chemistry.chemical_element ,micronutrientes ,General Medicine ,Zinc ,engineering.material ,biology.organism_classification ,lcsh:S1-972 ,crambe abyssinica hochst ,vigor ,lcsh:Agriculture ,chemistry.chemical_compound ,Horticulture ,chemistry ,Seedling ,Crambe ,Germination ,Molybdenum ,Seed treatment ,engineering ,Fertilizer ,lcsh:Agriculture (General) - Abstract
Objetivou-se avaliar a qualidade fisiológica de sementes de crambe tratadas com fertilizante a base de zinco e molibdênio. O experimento foi conduzido no Laboratório de Análise de Sementes da Unimontes. O delineamento experimental utilizado foi inteiramente casualizado, com quatro repetições. Os tratamentos testados constituíram de cinco doses de fertilizante comercial composto por zinco (35%) e molibdênio (3,5%), aplicados via semente nas concentrações de 0; 3,3; 6,7; 10 e 13 mL do fertilizante para 0,5 Kg-1 de sementes. A qualidade fisiológica das sementes foi avaliada por meio dos seguintes testes: germinação, primeira contagem de germinação, emergência de plântulas e comprimento de plântulas. Com o aumento das doses do fertilizante comercial composto por zinco e molibdênio, houve redução na germinação e vigor das sementes de crambe. A qualidade fisiológica das sementes de crambe é influenciada negativamente por doses crescentes de molibdênio.
- Published
- 2019
27. Bean cultivation in a subsistence farming system in the northeast of São Paulo state - Brazil
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Wladecir Salles de Oliveira and Siu Mui Tsai
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Phaseolus vulgaris ,Rhizobium tropici ,landrace ,lime ,molybdenum ,Agriculture (General) ,S1-972 - Abstract
The colonization of the State of São Paulo, Brazil of the northeastern region, is related to historical movements, such as "tropeirismo" (séc. XVIII and XIX) and Italian immigration (séc. XIX). The agriculture presently practices used by farmers descendent of immigrants does not differ from the techniques used at the beginning of the century. In the Cunha region of the Atlantic Rain Forest ecosystem poor bean yield associated with low fertilizer input, plant disease and soil erosion led to slash-and-burn farming. This work is an attempt at identifying sustainable farming practices that would minimize bean disease and maximize nitrogen assimilation. For that purpose soil fertility and plant cultivar were studied under standard agronomic practices to determine their effect on seed yield, total nitrogen of grain and number of root nodules. Fertilization, liming and molybdenum from 16 sites increased yield by 342% and 369% for the landrace `Serro Azul' and commercial variety `Carioca 80 SH', respectively. In addition, plants grown with fertilizer presented more nodules and more nitrogen in grain per hectare. The increase of crop yield per hectare might increment the family income and reduce deforestation of the Atlantic forest.
- Published
- 2001
28. Avaliação da influência de tratamentos superficiais na absortância e morfologia de filmes absorvedores de Mo/SiO2 obtidos via Sputtering
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Oliveira, Aline da Silva and Gomes, Kelly Cristiane
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Molibdênio ,Molybdenum ,Absortância ,Absorptance ,Superfície seletiva ,Sputtering ,ENGENHARIAS [CNPQ] ,Selective Surface ,SiO2 - Abstract
Sustainable development is directly related to renewable energy sources. Among these sources is the Sun, from which practically all the energy used on the planet derives. Solar energy can be used to generate electricity through photovoltaic modules or thermal power plants that use electric generators, or used to heat water in solar collectors for direct use. The good thermal performance of solar collectors depends on the selective coverage that covers the absorber plate of the collectors, known as selective surfaces, which are materials with high capacity to absorb solar radiation and low infrared emission. Various materials and layer configurations can be used in manufacturing selective surfaces. This work proposes the production of selective surfaces in multilayers of molybdenum (Mo) and silica (SiO2) in order to optimize the thermal performance of the system, comparing different parameters in the sputtering deposition technique, and evaluating the influence of the type of substrate treatment on this performance. The results obtained in UV-Visible and Near Infrared Spectrophotometry showed that the surface absorptance is higher for Mo and Mo/SiO2 films on electropolished surfaces compared to treatments with acid and hexane. The highest absorptance reached was 98.10% for a Mo/SiO2 film. Band gaps were estimated by the Tauc method and assumed values ranging from 0.7 to 3.45 eV. These values increase with increasing film thickness, increasing absorptance. Higher band gap values indicate the formation of Cr2O3 in the film. In electropolished samples it was determined the existence of more than one energy gap that is related to the higher absorptance of these samples. Fourier Transform Infrared Spectroscopy (FTIR) indicated the presence of residues of materials used in the surface treatments of substrates and characteristic bands of the vibration of Cr2O3 bonds from chemical passivation, and a marked band characteristic of SiO2 bonds. X-ray diffraction (XRD) exhibited peaks characteristic of the metallic Mo phase, and the presence of silica in the amorphous and crystalline phases in the form of quartz was also verified. The results obtained in Optical Profilometry indicate that the absorptance of the samples is influenced by the roughness of the substrates. The thickness and roughness of the films were evaluated using Atomic Force Microscopy (AFM), which determined thickness values characteristic of thin films. Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES O desenvolvimento sustentável relaciona-se diretamente com as fontes de energias renováveis. Entre essas fontes está o Sol, do qual deriva praticamente toda a energia usada no planeta. A energia solar pode ser aproveitada para a geração de eletricidade através dos módulos fotovoltaicos ou em usinas térmicas que empregam geradores elétricos, ou aproveitada para o aquecimento de água em coletores solares para uso direto. O bom desempenho térmico de coletores solares depende da cobertura seletiva que recobre a placa absorvedora dos coletores, conhecidas como superfícies seletivas, que são materiais com alta capacidade de absorção de radiação solar e baixa emissão no infravermelho. Diversos materiais e configurações de camadas podem ser usadas na fabricação de superfícies seletivas. Este trabalho propõe a produção de superfícies seletivas em multicamadas de molibdênio (Mo) e sílica (SiO2) afim de otimizar o desempenho térmico do sistema, comparando diferentes parâmetros na técnica de deposição de Sputtering, e avaliando a influência do tipo de tratamento do substrato nesse desempenho. Os resultados obtidos na Espectrofotometria na Região do UV-Visível e Infravermelho Próximo mostraram que a absortância das superfícies é superior para filmes de Mo e Mo/SiO2 em superfícies eletropolidas em comparação com os tratamentos com ácido e hexano. A maior absortância atingida foi de 98,10% para um filme de Mo/SiO2. Os band gaps foram estimados pelo método de Tauc e assumiram valores de variando de 0,7 a 3,45 eV. Esses valores aumentam com o aumento da espessura do filme, aumentando a absortância. Os valores de band gap mais altos indicam a formação de Cr2O3 no filme. Nas amostras eletropolidas foi determinada a existência de mais de um gap de energia que se relaciona com a maior absortância dessas amostras. A Espectroscopia no Infravermelho por Transformada de Fourier (FTIR) indicou a presença de resíduos dos materiais utilizados nos tratamentos superficiais dos substratos e bandas características da vibração de ligações de Cr2O3 proveniente da passivação química, e uma banda acentuada característica das ligações de SiO2. A difração de Raios X (DRX) exibiu picos característicos da fase de Mo metálico, sendo também verificado a presença da sílica na fase amorfa e cristalina na forma de quartzo. Os resultados obtidos na Perfilometria Óptica indicam que a absortância das amostras é influenciada pela rugosidade dos substratos. As espessuras e a rugosidade dos filmes foram avaliadas através da Microscopia de Força Atômica (AFM), que determinou valores de espessura característicos de filmes finos.
- Published
- 2021
29. TESTE DE GERMINAÇÃO E DE VIGOR EM SEMENTES DE MILHO TRATADAS COM MICRONUTRIENTES E FLAVONÓIDES.
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SEGATO, Silvelena Vanzolini
- Abstract
The range of products used for seed treatment is fungicide, insecticide, micronutrients, organic compounds and stimulants. The aimed to determine the germination and vigor of maize seeds treated with a product based on micronutrients and flavonoids. The experiment was conducted with three seed lots of maize (hybrid single, double and triple) of the same classification, treated and not treated with the product. In laboratory of the Faculty "Dr. Francisco Maeda," in Ituverava / SP held the germination test, accelerated aging and cold test. There is difference in performance of hybrid in corn seed treatment with micronutrients and flavonoids. Vigor tests are more sensitive to evaluate the performance of seeds treated with micronutrients and flavonoids. [ABSTRACT FROM AUTHOR]
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- 2015
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30. Tratamento de sementes de soja com micronutrientes Soybean seeds treated with micronutrients
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Sérgio de Assis Librelotto Rubin, Osmar Souza dos Santos, Nerinéia Dalfollo Ribeiro, and Ricardo Oscar Raupp
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soja ,calcário ,molibdênio ,cobalto ,zinco ,boro ,rendimento de grãos ,soybean ,lime ,molybdenum ,cobait ,zinc ,boron ,grain yield ,Agriculture ,Agriculture (General) ,S1-972 - Abstract
Foram conduzidos dois experimentos na Estação Experimental de Júlio de Castilhos, RS, nos anos agrícolas 1990/91 e 1991/92, a fim de verificar a resposta da soja à aplicação de zinco, boro, molibdênio e cobalto nas sementes, em duas doses de calcário no solo Passo Fundo (LE). Utilizou-se o delineamento blocos ao acaso, em parcelas subdivididas com três repetições, estabelecendo-se nas parcelas duas doses de calcário (sem e com 17,7t/ha) e nas subparcelas formulações de zinco, boro, molibdênio e cobalto (0,875; 0,062; 0,150 e 0,012g/kg de sementes) aplicadas nas sementes junto com o inoculante. Os tratamentos constaram de testemunha, molibdênio e zinco isolados, combinados entre si e associados a boro e cobalto, nas formulações em forma de pó (Biocrop Soja) e fluída (fonte experimental MIQL 44-90A). Os resultados obtidos evidenciam que, na condição sem calcário, os tratamentos de sementes com molibdênio aumentam o rendimento de grãos. Na condição com calcário, não há resposta a aplicação dos micronutrientes.The expenment was conducted in the Julio de Castilhos Experimental Station, RS, in 1990/91 and 1991/92 seasons. The effect of soybean seeds treated with zinc, boron, molybdenum and cobait, in two lime doses in Passo Fundo soil was evaluated. A completely randomized design with split plot with three replications was used. The lime doses formed the mam plots (zero and 17.71/ha) and zinc, boron, molybdenum and cobait formulation (0.875; 0.062; 0.150 and 0.012gkg of seeds) were the sub-plots. The treatments were contlol, molybdenum and zinc isolated and combinated with boron and cobait, with powder (Soybean Biocrop) and solution (MIQL 44-90A) formulation. The results indicate that withouth lime application, seeds treated with molybdenum had an increment in grain yield. However witht liming no difference in grain yield was observed.
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- 1995
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31. Eficiencia del producto Raigran® en el tratamiento de semillas en cultivo de maní
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Zampieri de Almeida, Luiz Fernando, Fonseca , Antonio Eduardo, Júnior , João Paulo, Ramos, Maria Fernanda, and da Silva, Thais Meirelles Rodrigues
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Molibdênio ,Molybdenum ,Arachis hypogaea L ,Cobalto ,molibdeno ,micronutrientes ,Micronutrients ,Cobalt - Abstract
The success of peanut crop production is related to the adequate supply of nutrients, which are essential for plant growth and development. The experiments were installed in order to evaluate the efficiency of Raigran compared to other products of different concentrations of Co and Mo in the treatment of peanut seeds. The installation took place at Estação Experimental Oxiquímica Agrociência Ltda, from October 2019 to March 2020. The statistical design used was completely randomized with seven replications and six treatments for the greenhouse test and the randomized blocks, with four repetitions and six treatments for the field trial. The treatments used were: Witness; Vitavax-Thiran® "‹"‹+ Cruiser®; Vitavax-Thiran® "‹"‹+ Cruiser® + Raigran®; Vitavax-Thiran® "‹"‹+ Cruiser® + Product 1; Vitavax-Thiran® "‹"‹+ Cruiser® + Product 2; Vitavax-Thiran® "‹"‹+ Cruiser® + Product 3. It was evaluated at 16 DAE in a greenhouse: length of the root and area, wet and dry mass of root and area. In the field trial, the percentage of germination and productivity at the end of the culture cycle was evaluated at 14 DAE. The product Raigran®, composed of Cobalt and Molybdenum, added to the Vitavax-Thiran® "‹"‹+ Cruiser® treatment, was efficient in the treatment of seeds, resulting in greater values "‹"‹of length (root and aerial part), wet and dry mass (root and part in greenhouse, and higher percentage of germination and productivity in field conditions. El éxito de la producción de cultivos de maní está relacionado con el suministro adecuado de nutrientes, que son esenciales para el crecimiento y desarrollo de las plantas. Los experimentos se instalaron con el fin de evaluar la eficiencia de Raigran en comparación con otros productos de diferentes concentraciones de Co y Mo en el tratamiento de semillas de maní. La instalación se llevó a cabo en la Estação Experimental Oxiquímica Agrociência Ltda, de octubre de 2019 a marzo de 2020. El diseño estadístico utilizado fue completamente al azar con siete repeticiones y seis tratamientos para la prueba de invernadero y los bloques al azar, con cuatro repeticiones y seis tratamientos para la prueba de campo. Los tratamientos utilizados fueron: Testigo; Vitavax-Thiran® "‹"‹+ Cruiser®; Vitavax-Thiran® "‹"‹+ Cruiser® + Raigran®; Vitavax-Thiran® "‹"‹+ Cruiser® + Producto 1; Vitavax-Thiran® "‹"‹+ Cruiser® + Producto 2; Vitavax-Thiran® "‹"‹+ Cruiser® + Producto 3. Se evaluó a los 16 DAE en invernadero: longitud de la raíz y parte del área, masa de raíz húmeda y seca y parte del área. En el ensayo de campo, se evaluó el porcentaje de germinación y productividad al final del ciclo de cultivo a los 14 dda. El producto Raigran®, compuesto de Cobalto y Molibdeno, agregado al tratamiento Vitavax-Thiran® "‹"‹+ Cruiser®, resultó eficiente en el tratamiento de semillas, resultando en mayores valores de longitud (raíz y parte aérea), masa húmeda y seca (raíz y parte en invernadero, y mayor porcentaje de germinación y productividad en condiciones de campo. O sucesso da produção da cultura de amendoim está relacionado com o adequado suprimento de nutrientes, os quais são fundamentais para o crescimento e desenvolvimento da planta. Os experimentos foram instalados com o objetivo avaliar a eficiência do Raigran comparados a outros produtos de diferentes concentrações de Co e Mo no tratamento de sementes de amendoim. A instalação ocorreu na Estação Experimental Oxiquímica Agrociência Ltda, durante os meses de outubro de 2019 a março de 2020. O delineamento estatístico utilizado foi inteiramente casualizados com sete repetições e seis tratamentos para o ensaio em casa de vegetação e o de blocos casualizados, com quatro repetições e seis tratamentos para o ensaio em campo. Os tratamentos utilizados foram: Testemunha; Vitavax-Thiran® + Cruiser®; Vitavax-Thiran® + Cruiser® + Raigran®; Vitavax-Thiran® + Cruiser® + Produto 1; Vitavax-Thiran® + Cruiser® + Produto 2; Vitavax-Thiran® + Cruiser® + Produto 3. Avaliou-se aos 16 DAE em casa de vegetação: comprimento de raiz e da parte área, massa úmida e seca de raiz e parte área. No ensaio de campo, avaliou-se aos 14 DAE a porcentagem de germinação e produtividade no final do ciclo da cultura. O produto Raigran®, composto por Cobalto e Molibdênio, adicionado ao tratamento Vitavax-Thiran® + Cruiser®, foi eficiente no tratamento de sementes, resultando em maiores valores de comprimento (raiz e parte aérea), massa úmida e seca (raiz e parte aérea) em casa de vegetação, e maior porcentagem de germinação e produtividade em condições de campo.
- Published
- 2020
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32. Determinação de Cd(II) e Pb(II) em fertilizantes minerais e Ti(IV), V(V) e Mo(VI) em águas estuarinas por voltametria de redissolução com pulso diferencial
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Krause, Cristian Henrique and Schneider, Alexandre Batista
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Molibdênio ,Titanium ,Molybdenum ,Stripping voltammetry ,Trace elements ,Eletrodos impressos ,Elementos-traço ,Vanádio ,Estuary ,Vanadium ,Trace analysis ,Screen-printed electrodes ,Cádmio ,Chumbo ,Lead ,Estuário ,Fertilizantes minerais ,Voltametria de redissolução anódica ,Mineral fertilizers ,Titânio ,Análise de traços ,Cadmium - Abstract
Esta dissertação apresenta dois capítulos, sendo o primeiro tratando-se do desenvolvimento de um método de voltametria de redissolução anódica para a determinação simultânea de Cd(II) e Pb(II) em fertilizantes minerais empregando-se eletrodos impressos de carbono modificados com nanotubos de carbono funcionalizados com grupos carboxílicos e formação in situ de filme de bismuto (Bi-SPE/SWCNT-COOH) e um potenciostato portátil. Realizou-se a otimização dos parâmetros experimentais usando-se como eletrólito suporte tampão acetato de amônio 1 mol L-1 pH 4,6. A validação do método envolveu testes de recuperação em amostras fortificadas com resultados entre 85% e 98% para Cd(II) e 96% e 112% para Pb(II) e pela medida de material de referência certificado (MRC) – NIST 695. Foram calculados valores de LD de 1,0 μg L-1 e LQ de 3,4 μg L-1 para cádmio e LD de 0,7 μg L-1 e LQ de 2,3 μg L-1 para chumbo e o método foi aplicado em amostras reais. O segundo capítulo envolveu a utilização de eletrodo de gota pendente de mercúrio (do inglês hanging mercury drop electrode, HMDE) na determinação de Ti(IV), V(V) e Mo(VI) em amostras dos estuários dos rios Amazonas e Pará para a avaliação posterior de processos envolvendo as fontes, distribuições e fracionamento destas espécies ao longo do gradiente de salinidade da mistura estuarina. Os métodos aqui aplicados se basearam na adsorção de complexos dos metais, Ti(IV)-cupferron, V(V)-cupferron e Mo(VI)-ácido mandélico na superfície do eletrodo através da voltametria adsortiva de redissolução. Os resultados mostraram que Mo(VI) manteve um perfil conservativo de concentração, e sua concentração aumentou com a salinidade; V(V) também apresentou um perfil conservativo de concentração, mas com dados mais dispersos do que Mo(VI); já Ti(IV) mostrou uma queda acentuada da concentração nas salinidades iniciais, o que é esperado para um elemento reativo a particula, seguido de algumas variações ao longo do estuário, devido à sua natureza não-conservativa. Além do mais, Ti(IV) dissolvido apresentou diferentes concentrações após filtração e ultrafiltração por tamanhos de poro 0,2 μm, 0,015 μm, 10 kDA e 1 kDA. This dissertation has two chapters, the first being about the development of an anodic stripping voltammetry method for the simultaneous determination of Cd(II) and Pb(II) in mineral fertilizers with screen-printed carbon electrodes modified with carboxyl functionalized single-walled carbon nanotubes and in situ bismuth film formation (Bi-SPE/SWCNT-COOH) and a portable potenciostat. Experimental parameters optimization was performed in ammonium acetate buffer 1 mol L-1 pH 4,6 as the support electrolyte. Recovery tests in fortified samples were performed for the method validation with results between 85% e 98% for Cd(II) and 96% e 112% for Pb(II), recovery tests were also carried out by the measurement of certified reference material (MRC) – NIST 695. LD values of 1,0 μg L-1 and LQ of 3,4 μg L-1 were calculated for cadmium and LD of 0,7 μg L-1 and LQ of 2,3 μg L-1 for lead, the method was applied in real samples. In the second chapter the hanging mercury drop electrode (HMDE) was applied for the determination of Ti(IV), V(V) and Mo(VI) in samples from the Amazon river estuary and Pará river estuary for later evaluation of processes including sources, distribution and speciation of the these species along the salinity gradient of the estuarine mixture. The applied methods are based on the adsorption of metal complexes, Ti(IV)-cupferron, V(V)-cupferron and Mo(VI)-mandelic acid on the electrode surface through adsorptive stripping voltammetry. Results showed Mo(VI) maintained a conservative concentration profile, its concentration increases as the salinity increases; V(V) also presented a conservative concentration profile, but with more dispersed data than Mo(VI); Ti(IV) concentration showed a sharp drop in initial salinities, this is expected for a reactive particle element, it also showed small concentration variations along the estuary due to its non-conservative nature. Furthermore, dissolved Ti(IV) showed different concentrations after 0,2 μm and 0,015 μm pore size filtration and 10 kDA e 1 kDA pore size ultrafiltration.
- Published
- 2020
33. Viabilidade do inoculante turfoso produzido com bactérias associativas e molibdênio.
- Author
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Guimarães, Salomão Lima, Baldani, Vera Lúcia Divan, and Jacob-Neto, Jorge
- Abstract
Copyright of Revista Ciência Agronômica is the property of Revista Ciencia Agronomica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2013
34. Uso de pontas CVD acopladas ao ultrassom para preparo cavitário.
- Author
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de MELLO E OLIVEIRA, Rafael, do AMARAL, Flávia Lucisano Botelho, PECORARI, Vanessa Gallego Arias, FRANÇA, Fabiana Mantovani Gomes, and BASTING, Roberta Tarkany
- Subjects
DENTAL cavity preparation ,ULTRASONIC imaging ,OPERATIVE dentistry ,DENTAL drilling ,MOLYBDENUM ,COMPOSITE coating ,DENTAL amalgams - Abstract
Copyright of Revista Dental Press de Estética is the property of Dental Press International and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2012
35. Sintomas de deficiência de macro e micronutrientes de plantas de milho híbrido BRS 1010.
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Ferreira, Magna Maria Macedo
- Subjects
MICRONUTRIENTS ,HYBRID corn ,MAGNESIUM ,EXPERIMENTAL design ,MOLYBDENUM ,NITROGEN ,COPPER - Abstract
Copyright of Revista Agro@mbiente On-line is the property of Revista Agro@mbiente On-line and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2012
- Full Text
- View/download PDF
36. MIGRAÇÃO DE MOLIBDÊNIO NA INTERFACE MATRIZ/ PRECIPITADO EM METAIS DE SOLDA DE LIGAS Ni-Cr-Mo.
- Author
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Silva, Cleiton Carvalho, Afonso, Conrado Ramos Moreira, de Miranda, Hélio Cordeiro, Ramirez, Antonio Jose, and Farias, Jesualdo Pereira
- Subjects
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METALS , *MOLYBDENUM alloys , *X-ray spectroscopy , *SCANNING electron microscopy , *TRANSMISSION electron microscopy , *MANUFACTURING processes - Abstract
This work evaluates the chemistry elements distribution on matrix/precipitate interface in a Ni-Cr-Mo-W alloy weld metals deposited on substrate of C-Mn steel. Microestructural characterization was carried out through optical microscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) techniques. The results have shown that the presence of secondary phases precipitates in the interdendritic region. Through SEM analysis indications of migration of molybdenum around these phases are observed. These precipitates are identified as P-phase by TEM analysis. The molybdenum migration along matrix/precipitate interface is confirmed through EDS. The phenomenon of molybdenum migration is a result of a re-heating due to several welding heat cycles deposited to promote the coating layer. [ABSTRACT FROM AUTHOR]
- Published
- 2011
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37. ADUBAÇÃO MOLÍBDICA NA CULTURA DO FEIJÃO NOS SISTEMAS DE PLANTIO DIRETO E CONVENCIONAL.
- Author
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ROCHA, PAULO ROBERTO RIBEIRO, ARAÚJO, GERALDO ANTÔNIO DE ANDRADE, CARNEIRO, JOSé EUSTÁQUIO DE SOUZA, CECON, PAULO ROBERTO, and LIMA, TRICIA COSTA
- Subjects
MOLYBDENUM ,NO-tillage ,CONSERVATION tillage ,BLOCK designs ,GRAIN ,SOIL management - Abstract
Copyright of Revista Caatinga is the property of Revista Caatinga and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
- Published
- 2011
38. Nitrogênio em cobertura e molibdênio foliar no feijoeiro de inverno.
- Author
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Barbosa, Giselle Feliciani, Arf, Orivaldo, do Nascimento, Martha Santana, Salatiér Buzetti, and da Silva Freddi, Onã
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RHIZOBIUM , *NITROGEN , *TILLAGE , *AGRICULTURE , *RHIZOBIACEAE , *PLANT propagation , *MOLYBDENUM , *SYMBIOSIS , *BIOLOGY - Abstract
Side dressing nitrogen and leaf molybdenum in the winter common bean plant. The common bean has the capacity of nitrogen fixation in symbiosis with Rhizobium, but it is not enough to supply the necessities of the plant in relation to this nutrient. Molybdenum application aims to improve symbiosis in the Rhizobium-common bean plant, given its importance in the metabolism of this nutrient, thus being able to reduce the application of N fertilizer. Thus, the objective of the work was to evaluate the performance of irrigated winter beans, in a no-tillage system, with increasing levels of side dressing nitrogen application (zero, 30, 60, 90 and 120 kg ha-1) and its interaction with leaf application of Mo (zero and 80 g ha-1). The experimental design was randomized blocks in a 5 x 2 factorial scheme, with four repetitions. The research was carried out on soil previously cultivated with corn culture. The levels of nitrogen proved consistent regarding the effects on some production components, as well as on dry mass of plants, providing better development of irrigated beans cultivated under no-tillage. The application of molybdenum in leaves did not significantly influence the majority of evaluated parameters. [ABSTRACT FROM AUTHOR]
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- 2010
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- View/download PDF
39. Combinações de doses de molibdênio e nitrogenio na adubação da cultura do feijoeiro-comum.
- Author
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de Andrade Ara ú jo, Paulo Roberto, de Andrade Ara ú jo, Geraldo Antônio, Rocha, Paulo Roberto Ribeiro, and de Souza Carneiro, José Eustáquio
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MOLYBDENUM , *COMMON bean , *PLANT fertilization , *NITROGEN , *KIDNEY bean , *FOLIAR feeding , *PLANT nutrition , *SOWING , *LEAVES - Abstract
Combinations of molybdenum and nitrogen doses on common bean fertilization. Two experiments were carried out, one in summer-autumn and the other during spring-summer, in Coimbra, Minas Gerais State, in order to evaluate the effect of different doses of nitrogen and molybdenum on bean plants. The experimental design was randomized blocks, with four repetitions, in a 4 × 2 × 2 factorial arrangement, consisting of four levels of molybdenum (0, 40, 80 and 120 g ha-1), applied by foliar spraying at 25 days after plant emergence, two doses of nitrogen during sowing (0 and 20 kg ha-1) and two doses of nitrogen applied on the surface (0 and 50 kg ha-1). In the presence and in the absence of nitrogen in the planting or on the surface, the increment of the molybdenum dose up to 80 g ha-1 elevates the number of pods per plant and the productivity of grains of bean. In general, increasing doses of molybdenum also elevate the number of grains of bean per pod and the mass of 100 seeds, but these effects are more dependent on the presence of sowing nitrogen or surface. The effects of molybdenum on the level of N in the leaves, molybdenum content in the seed and SPAD readings are less solid; for this reason, they should not be generalized. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
40. QUALIDADE DAS SEMENTES DE SOJA COM A APLICAÇÃO DE DIFERENTES DOSES DE MOLIBDÊNIO E COBALTO.
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Golo, André Luis, Kappes, Claudinei, de Carvalho, Marco Antonio Camillo, and Yamashita, Oscar Mitsuo
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SOYBEAN , *SEED physiology , *SEED viability , *PLANT physiology , *PLANT mechanics , *CULTIVARS , *COBALT , *MOLYBDENUM - Abstract
The present work study assessed the effect of foliar application of different doses of cobalt (Co) and molybdenum (Mo), and seed inoculation with Bradyrhizobium japonicum on the productive characteristics of the soybean crop and the quality of its seeds. The study was carried out in 2005/06, in a Red-Yellow Latosol (Hapludox) dystrophic soil, in the city of Santa Carmen, MT. The experimental design was a randomized block in a 6 X 2 factorial design, with a combination of 12 treatments with four replications for each treatment. The treatments resulted from the combination of six doses of the product Quimifol CoMo Plus (0.0; 0.25; 0.5; 1.0; 1.5; and 2.0 L ha-1), applied foliarly, with and without inoculation of the seeds with a liquid formulation of Bradyrhizobium japonicum, RizoLiq. Based on the results, the following conclusions were drawn: seed inoculation with Bradyrhizobium increased the number of pods per plant and the number of seeds per plant; the doses of CoMo affected the mass of 100 seeds and the grain yield; inoculation did not result in increases in grain yield; the application of 2 L ha-1 CoMo to inoculated seed improved the seed physiological quality; in the absence of inoculation, increasing doses of CoMo caused decrease in seed physiological quality. [ABSTRACT FROM AUTHOR]
- Published
- 2009
- Full Text
- View/download PDF
41. Catalisadores de ferro e molibdênio suportado em carvão ativado para reação de hidrogenólise de derivados de biomassa
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Mateus, Viviana Oliveira, Mascarenhas, Artur José Santos, Rosário, Adriane Viana do, Alves Júnior, Raildo Fiuza, Pontes, Luiz Antônio Magalhães, and Paula, Rodrigo de
- Subjects
Molibdênio ,Molybdenum ,Carvão ativado ,Activated carbon ,Iron ,Química ,Biomassa ,Iron Catalysts ,Hidrogenólise ,Catalisadores de ferro ,Ciências Exatas e da Terra ,Biomass ,Hydrogenolysis ,Ferro - Abstract
Submitted by Luciana Silva (lucianassaraujo@ufba.br) on 2021-08-27T15:40:18Z No. of bitstreams: 1 VIVIANA OLIVEIRA MATEUS_Versão final tese.pdf: 6938515 bytes, checksum: 8003d8ccf49336eb295fb61ef8382a8b (MD5) Approved for entry into archive by Solange Rocha (soluny@gmail.com) on 2021-08-31T21:26:16Z (GMT) No. of bitstreams: 1 VIVIANA OLIVEIRA MATEUS_Versão final tese.pdf: 6938515 bytes, checksum: 8003d8ccf49336eb295fb61ef8382a8b (MD5) Made available in DSpace on 2021-08-31T21:26:16Z (GMT). No. of bitstreams: 1 VIVIANA OLIVEIRA MATEUS_Versão final tese.pdf: 6938515 bytes, checksum: 8003d8ccf49336eb295fb61ef8382a8b (MD5) A inserção de matéria advinda de fontes inesgotáveis é requerida pelo comércio e, portanto, a indústria. A biomassa surgi como uma alternativa promissora na diversificação das plataformas utilizadas industrialmente, a transformação da biomassa direcionada a processos que garantam preços competitivos em relação aos advindos dos combustíveis fósseis é desejável. Catalisadores ácidos são requeridos no processo, no sentido de favorecer a hidrólise da celulose nas reações de hidrogenólise da celulose para auxiliar na formação dos açucares e na desidratação do glicerol a acroleína nas reações de hidrogenólise do glicerol, por exemplo. Em contrapartida as características metálicas dos catalisadores tendem a favorecer a hidrogenação levando a formação do 1,2 e 1,3 propanodiol nas reações de hidrogenólise do glicerol e a sorbitol nas reações de hidrogenólise da celulose. Comumente, a hidrogenólise é empregada no sentido de proporcionar a quebra das ligações C-C e C-O que compõem a estrutura da biomassa como as da celulose e a do glicerol. Os efeitos das características ácidas e metálicas dos catalisadores, portanto, tendem a favorecer ao processo da quebra das rígidas ligações presentes na celulose, bem como no direcionamento das reações de hidrogenólise do glicerol a formação de insumos químicos muito requerido pela indústria como o propeno em condições brandas de reação. Os catalisadores contendo molibdênio e ferro suportados em carvão parece ser um caminho promissor, por possuir características ácidas e texturais que provavelmente favoreçam a conversão da celulose, bem como a do glicerol. O emprego do carvão ativado neste caso, para favorecer a dispersão dos catalisadores e, portanto, a disponibilidade dos centros ativos para reagir. Neste contexto, o estudo de catalisadores de ferro e molibdênio suportado em carvão ativado para reação de hidrogenólise de derivados de biomassa (hidrogenólise da celulose e hidrogenólise do glicerol) foi estudado e explicitado as muitas características apreciáveis para seu uso nestas reações. A hidrogenólise do glicerol à 500 ºC mostrou ser mais promissora para a obtenção de propeno nos catalisadores contendo molibdênio, enquanto à 300ºC mostrou ser mais seletiva para a obtenção de metano, etano, eteno ou CO. A produção de propeno apresentou rendimento de 15 % ao total das 6 horas de reação à 500 ºC para o CMF. A caracterização pós teste dos catalisadores submetidos à 300 ºC e 500ºC indicou que as fases discutidas no TPR na caracterização foram obtidas e, portanto, as fases Fe2MoO4, Fe2Mo3O8, FeMoO4, MoO2, Fe nas amostras contendo molibdênio e ferro, bem como a fase Mo8O23 foram observadas. O TG pós teste catalítico indicou presença de grande quantidade de óxidos para todos os casos. A hidrogenólise da celulose realizadas a 205ºC mostrou ser promissora na obtenção das moléculas de HMF e furfural s 50 bar. O catalisador CF indicou favorecer a formação do glicerol, CM ao HMF e furfural e o CMF à formação do HMF e acetol majoritariamente. Os resultados indicaram que a acidez governa a reação, bem como a fase ativa. Estes resultados indicam que a hidrogenação foi favorecida no catalisador CF, enquanto que o CM e CMF ocorreu a hidrogenólise provavelmente. A pressão de 50 bar pode ter favorecido à redução in situ do catalisador e possivelmente os mecanismos da hidrogenólise da celulose foi favorecida para o CM e CMF. The insertion of matter from inexhaustible sources is required by commerce and therefore industry. Biomass has emerged as a promising alternative in the diversification of the industrial platforms, the transformation of biomass directed to processes that guarantee competitive prices in relation to those coming from fossil fuels is desirable. Acid catalysts are required in the process in order to favor the hydrolysis of cellulose in the hydrogenolysis reactions of cellulose to aid in the formation of sugars and the dehydration of glycerol to acrolein in the hydrogenolysis reactions of glycerol, for example. In contrast, the metallic characteristics of the catalysts tend to favor hydrogenation leading to the formation of 1,2 and 1,3 propanediol in the hydrogenolysis reactions of glycerol and sorbitol in the hydrogenolysis reactions of the cellulose. Commonly, hydrogenolysis is employed in the sense of providing breakage of the C-C and C-O bonds that make up the structure of the biomass such as cellulose and glycerol. The effects of the acidic and metallic characteristics of the catalysts, therefore, tend to favor the process of breaking the rigid bonds present in the cellulose, as well as in the direction of the reactions of hydrogenolysis of the glycerol, the formation of chemical inputs much required by industry as propene under conditions reactions. The catalysts containing molybdenum and iron supported on charcoal seem to be a promising route, as it has acidic and textural characteristics that probably favor the conversion of cellulose, as well as that of glycerol. The use of the activated carbon in this case, to favor the dispersion of the catalysts and, therefore, the availability of the active centers to react. In this context, the study of iron and molybdenum catalysts supported on activated carbon for the reaction of hydrogenolysis of biomass derivatives (hydrogenolysis of cellulose and hydrogenolysis of glycerol) was studied and the many appreciable characteristics for its use in these reactions were explained. Hydrogenolysis of glycerol at 500 ºC proved to be more promising for obtaining propylene in catalysts containing molybdenum, while at 300 ºC it proved to be more selective for obtaining methane, ethane, ethylene or CO. Propylene production yielded 15% of the total 6 hours of reaction at 500 ºC for CMF. The post-test characterization of catalysts submitted to 300 ºC and 500ºC indicated that the phases discussed in the TPR in the characterization were obtained and, therefore, the Fe2MoO4, Fe2Mo3O8, FeMoO4, MoO2, Fe phases in the samples containing molybdenum and iron, as well as the Mo8O23 phase were observed. The TG post catalytic test indicated the presence of a large amount of oxides for all cases. Hydrogenolysis of cellulose carried out at 205ºC has shown promise in obtaining HMF and furfural molecules at 50 bar. The catalyst CF indicated favoring the formation of glycerol, CM to HMF and furfural and CMF to the formation of HMF and acetol mainly. The results indicated that acidity governs the reaction, as well as the active phase. These results indicate that hydrogenation was favored in the CF catalyst, while CM and CMF probably occurred in hydrogenolysis. The 50 bar pressure may have favored the in situ reduction of the catalyst and possibly the mechanisms of cellulose hydrogenolysis were favored for CM and CMF.
- Published
- 2019
42. Evaluation of the influence of precipitation of intermetallic phases on corrosion resistance of superferritic stainless steel
- Author
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Pereira, Ursula Cid and Araújo, Walney Silva
- Subjects
Molibdênio ,Aço inoxidável ,Molybdenum ,Resistência à corrosão ,Superferritic stainless steel ,Thermic treatments ,Corrosion resistance ,Ciência dos materiais ,Aço - Tratamento térmico - Abstract
Superferritic steels are characterized by high chromium content (exceeding 25 wt%) and also have molybdenum in their composition. Meantime, superferritic stainless steels were developed for use in heat exchangers and marine environments. The high concentration of alloying elements in the superferritic stainless steels can affect the microstructural stability causing the precipitation of intermetallic phases, such as sigma (σ), chi (χ) and alpha line (α '). In order to understand how the precipitation of intermetallic phases influences in the corrosion resistance of superferritic steels, thus experimental alloys have been developed: Fe-25% Cr-XMo-YNi (X = 5 and 7%, Y = 2 and 4%). Heat treatments for 15 min, 1 h, 10 h, and 100 h at temperatures of 600oC, 700°C, 800°C and 900°C were performed and the results obtained were compared with the solubilized samples. Microstructural characterization of the samples and analysis of the precipitates were attained by optical microscopy and scanning electron microscopy equipped with energy dispersive spectrometry. The corrosion resistance was evaluated by linear cyclic polarization, electrochemical impedance spectroscopy, chronoamperometry and critical pitting temperature techniques. The solution of 3.5% NaCl was used as electrolyte and tests were realized in triplicate. Results showed that the 7Mo4Ni alloy presented better performance in corrosion resistance compared to other samples treated at the same time (100 h) and samples treated with 15 min, 1 h and 10 h the 7Mo2Ni alloy presented better performance in corrosion resistance. Os aços superferríticos são caracterizados pelo alto teor de cromo (superior a 25% p) e molibdênio em sua composição. Esses aços foram desenvolvidos inicialmente para uso em trocadores de calor e ambientes marinhos. Entretanto, a alta concentração de elementos de liga nos aços inoxidáveis superferríticos pode afetar a estabilidade microestrutural provocando a precipitação de fases intermetálicas, tais como: sigma (σ), chi (χ) e alfa linha (α’). Para entender como a precipitação das fases intermetálicas influencia na resistência à corrosão dos aços superferríticos, foram desenvolvidas ligas experimentais desses aços: Fe-25%Cr-XMo-YNi (X= 5 e 7%; Y = 2 e 4%). Tratamentos térmico de 15 min, 1h, 10h e100 horas nas temperaturas de 600, 700, 800 e 900°C foram realizados e comparado o resultado com as amostras apenas solubilizadas. Foram realizadas caracterização microestrutural das amostras e análise dos precipitados por meio de microscopia ótica, microscopia eletrônica de varredura com microanálise química por espectrometria de energia dispersiva. Para avaliar a resistência à corrosão foram utilizadas as técnicas de monitoramento de potencial de circuito aberto, polarização linear cíclica, espectroscopia de impedância eletroquímica, cronoamperometria e temperatura crítica de pite. Uma solução de 3,5% NaCl foi utilizada como eletrólito e todos os ensaios foram realizados em triplicata. Adicionalmente, as variações nas propriedades mecânicas causadas pela precipitação de fases intermetálicas, foram investigadas por meio de medidas de microdureza Vickers. Resultados mostraram que a liga 7Mo4Ni apresentou melhor desempenho na resistência à corrosão das amostras tratadas em 100 horas e para as amostras tratadas em 15 min, 1 h e 10 horas a liga 7Mo2Ni apresentou o melhor desempenho na resistência à corrosão.
- Published
- 2019
43. Preparation and optical characterization of fine films of silica/organic doped with molibdenio
- Author
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Scarpa, Elaine Ziviani [UNESP], Universidade Estadual Paulista (Unesp), and Vicente, Fábio Simões de [UNESP]
- Subjects
Molibdênio ,Molybdenum ,Sol-gel ,Filmes fotossensíveis ,Sílica/orgânico ,Photosensitive films ,Photochromism ,Fotocromismo ,Silica/organic - Abstract
Submitted by Elaine Ziviani Scarpa (scarpa_12@yahoo.com.br) on 2018-12-20T11:13:18Z No. of bitstreams: 1 Dissertação ELAINE ZIVIANI SCARPA.pdf: 8019246 bytes, checksum: 7b48f6351132b2cf2eba1e6fcd6bff55 (MD5) Rejected by Adriana Aparecida Puerta null (dripuerta@rc.unesp.br), reason: Prezada Elaine, O documento enviado para a coleção Campus Unesp Rio Claro foi recusado pelo(s) seguinte(s) motivo(s): - Folha de aprovação está incompleta (Norma ABNT NBR 14724). Falta constar a informação do Resultado: "APROVADO". Agradecemos a compreensão e aguardamos o envio do novo arquivo. Atenciosamente, Biblioteca Campus Rio Claro Repositório Institucional UNESP https://repositorio.unesp.br on 2018-12-20T12:11:41Z (GMT) Submitted by Elaine Ziviani Scarpa (scarpa_12@yahoo.com.br) on 2018-12-20T12:27:48Z No. of bitstreams: 1 Dissertação ELAINE ZIVIANI SCARPA.pdf: 8012376 bytes, checksum: f13a6bde0292e07072062b4bc9571cbc (MD5) Approved for entry into archive by Adriana Aparecida Puerta null (dripuerta@rc.unesp.br) on 2018-12-20T12:58:02Z (GMT) No. of bitstreams: 1 scarpa_ez_me_rcla.pdf: 8012376 bytes, checksum: f13a6bde0292e07072062b4bc9571cbc (MD5) Made available in DSpace on 2018-12-20T12:58:02Z (GMT). No. of bitstreams: 1 scarpa_ez_me_rcla.pdf: 8012376 bytes, checksum: f13a6bde0292e07072062b4bc9571cbc (MD5) Previous issue date: 2018-12-06 Filmes fotocrômicos dopados com heteropoliânions de molibdênio apresentam interessantes propriedades ópticas e fotocatalíticas com aplicações em inúmeras áreas desde materiais para optoeletrônica até células de combustível e energia. Neste trabalho materiais híbridos de sílica/orgânico dopados com o ácido fosfomolíbdico, H3PMo12O40, (HPMo) foram preparados na forma de filmes finos para estudo das propriedades ópticas e fotossensibilidade por exposição dos filmes finos a radiação ultravioleta. A matriz de sílica/orgânico no estado coloidal foi sintetizada através do processo sol-gel a partir da hidrolise ácida dos alcóxidos de silício 3-glicidoxipropiltrimetoxisilano (GPTS) e tetraetilortosilicato (TEOS). A matriz de sílica/Orgânico foi dopada com HPMo dissolvido em acetonitrila (ACN) e tetrahidrofurano (THF) e um segundo conjunto de amostras dopada com HPMo:THF e HPMo:ACN com a adição de Cloreto de Cobre (CuCl). Filmes finos fotossensíveis foram preparados por deposição das matrizes coloidais de sílica/orgânico dopadas com HPMo:ACN e HPMo:THF (HA e HT) e dopadas com HPMo:ACN:CuCl e HPMo:THF:CuCl (HAC e HTC). Pela técnica de absorção óptica e/ou transmitância na região do UV/VIS foi possível estudar os processos fotossensíveis nestas amostras, como o surgimento de bandas de absorção na região UV-VIS após exposição das amostras a luz UV (fotoescurecimento por redução do Mo+6→ Mo+5) e a velocidade do processo (constantes de tempo) e sua reversibilidade (clareamento, Mo+5→ Mo+6). Os conjuntos de amostras HA, HT, e HAC, HTC apresentaram intenso fotocromismo reversível, sendo que as amostras com adição de CuCl (HAC, HTC) apresentaram maior velocidade para o processo de clareamento comparado as amostras sem cobre. Medidas de transmitância in situ em 780 nm durante a exposição das amostras ao UV e após cessada a exposição ao UV com a amostra submetida a diferentes temperaturas durante o processo possibilitaram determinar as constantes de tempo do processo de clareamento que é ativado termicamente. A partir das constantes de tempo de clareamento para diferentes temperaturas determinamos a energia de ativação das diferentes composições de amostras. As amostras HA e HAC apresentaram energia de ativação de 24,9 KJ/mol e 20,7 KJ/mol, respectivamente, e as amostras HT e HTC apresentaram energia de ativação de 28,0 KJ/mol e 13,9 KJ/mol, respectivamente. Nos casos dos dois solventes utilizados com o molibdênio, as amostras com adição de cobre apresentaram menor energia de ativação do processo de clareamento. Photochromic films doped with molybdenum heteropolyanion present interesting optical and photocatalytic properties with applications in several areas such as optoelectronics, fuel cells and energy. In this work thin films of Silica/organic hybrid materials doped with phosphomolybdic acid H 3 PMo 12 O 40 , (HPMo) were prepared for the study of the photosensitivity with exposition to UV light. Colloidal Silica/organic hybrid matrix was synthesized by sol-gel process via acid hydrolysis of 3- glycidoxypropyltrimethoxysilane (GPTS) and tetraethylorthosilicate (TEOS) silicon alkoxides. The colloidal Silica/organic matrix was doped with HPMo dissolved into acetonitrile (ACN) and tetrahydrofuran (THF) and also HPMo in ACN and HPMo in THF with addition of copper chloride (CuCl). Photosensitive thin films were deposited by dip- coating from Silica/organic colloidal matrix doped with HPMo:ACN and HPMo:THF (HA e HT) and also HPMo:ACN:CuCl e HPMo:THF:CuCl (HAC e HTC). The photosensitivity of the samples was studied by UV-VIS optical absorption spectroscopy allowing indentifying the rising of absorption bands aroud 780 nm after UV irradiation of the films (photodarkening related to Mo +6 → Mo +5 ) and also the reversibility of the process without UV (bleaching due to Mo +5 → Mo +6 ). Samples HA, HT, e HAC, HTC showed strong reversible photodarkening and the samples doped with copper (HAC, HTC) showed a faster bleaching process compared with samples without copper. Optical transmittance at 780 nm was measured in-situ during samples UV irradiation and also after UV irradiation at different samples temperature allowing determining the time constants of the bleaching process and also the activation energy for the different samples compositions. Film samples HA and HAC presented activation energy of 24,9 KJ/mol and 20,7 KJ/mol, respectively, and the film samples HT and HTC presented activation energy of 28,0 KJ/mol and 13,9 KJ/mol, respectively. In both cases of the two solvents used with molybdenum, the film samples with copper showed lower activation energy for the bleaching process.
- Published
- 2018
44. Estudo do processo de fabricação de alvos de folhas finas de urânio metálico para produção de Mo-99
- Author
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José Antonio Batista de Souza, Michelangelo Durazzo, Elita Fontenele Urano de Carvalho, Cláudia Terezinha Kniess, Nelson Batista de Lima, and João Manoel Losada Moreira
- Subjects
sheets ,Materials science ,uranium 238 target ,infrared spectra ,Analytical chemistry ,Infrared spectroscopy ,chemistry.chemical_element ,x-ray emission spectroscopy ,physical properties ,rmb reactor ,molybdenum ,chemistry ,Molybdenum ,laser spectroscopy ,X Ray Emission Spectroscopy ,Spectroscopy ,isotope production ,chemical properties ,x-ray fluorescence analysis ,isotope production reactors - Abstract
O Tecnécio-99m (99mTc), gerado a partir do decaimento do Molibdênio-99 (99Mo), é o radionuclídeo mais conveniente para a execução de procedimentos de diagnósticos médicos, devido à sua emissão gama bem característica e de fácil detecção. O método utilizado para produzir 99Mo é através da fissão do 235U incorporado nos chamados alvos de irradiação. Duas rotas estão sendo desenvolvidas para a produção do 99Mo por fissão para o Reator Multipropósito Brasileiro (RMB), ambas utilizando urânio de baixo enriquecimento (LEU): 1) A primeira a dissolução básica, que é baseada na tecnologia de alvos de dispersão UAlx-Al. 2) A segunda emprega a dissolução ácida de alvos de folhas finas de urânio metálico. A principal vantagem dos alvos de folha fina de urânio metálico sobre os alvos de dispersão UAlx-Al é a alta densidade do urânio metálico. Com o intuito de compreender e otimizar o processo de fabricação de alvos de folhas finas foi realizado um estudo da fusão do urânio metálico, laminação de folhas finas, caracterização microestrutural e montagem dos alvos, definindo assim, os procedimentos específicos para a produção desse tipo de alvo com as características dos alvos fabricados internacionalmente. Os resultados obtidos mostraram que o processo de fabricação dos lingotes e de lâminas de urânio metálico por meio de laminação a quente possibilitaram a obtenção de lâminas com espessura entre 250 e 300 μm. O processo de laminação a frio possibilitou a obtenção de folhas finas com espessura de ±125 μm que atende à especificação internacional. O uso de óxido de alumínio como material para prevenir caldeamento do tablete de urânio mostrou-se eficiente, substituindo com vantagens o uso de óxido de ítrio. A microestrutura após o tratamento térmico apresentou grãos equiaxiais pequenos, e a realização de um resfriamento rápido de 5 minutos após o tratamento térmico foi suficiente para se eliminar a textura da folha fina de urânio metálico. O processo de montagem das folhas finas no alvo tubular foi realizado por pré-conformação da folha fina, facilitando a montagem. O processo de consolidação do alvo foi realizado por expansão por tração e a folga após a consolidação (\"gap de ar\") mostrou-satisfatória. As dimensões finais dos alvos tubulares atenderam à especificação internacional. Technetium-99m (99mTc) is generated from the decay of Molybdenum-99 (99Mo). This element is the most convenient radionuclide for application in medical diagnostic procedures, once that its gamma emission is well known and of easily detected. The method used to produce 99Mo is through fission of the 235U embedded in so-called irradiation targets. Two routes are being developed for the production of 99Mo per fission to the Brazilian Multipurpose Reactor (RMB), both using low enriched uranium (LEU): 1) The first basic dissolution, which is based on the technology of dispersion targets UAlx-Al. 2) The second employs the acidic dissolution of thin sheet targets of metallic uranium. The main advantage of uranium metal foil targets on the UAlx-Al dispersion targets is the high density of metallic uranium. In order to understand and optimize the process of manufacturing thin sheet targets, about the fusion of metallic uranium, thin sheet lamination, microstructural characterization and assembly of the target was carried out. Therefore the specific procedures for the production of this type of target with the characteristics of the targets manufactured internationally could be defined. The results showed that the process of manufacturing ingots and sheets of metallic uranium by hot rolling allows obtaining sheets with thickness between 250 and 300 μm. The cold rolling process allows obtaining thin sheets with a thickness of ± 125 μm which are in accordance with the international specification. The use of aluminum oxide as a material to prevent uranium tablet firing proved to be efficient, replacing with advantage the use of yttrium oxide. The microstructure after the heat treatment showed small equiaxial grains. A fast cooling of 5 minutes after the heat treatment was enough to eliminate the texture of the thin sheet of metallic uranium. The process of assembling the thin sheets in the tubular target was performed by preforming the thin sheet, facilitating the assembly. The process of consolidating the target was performed by tensile expansion and the clearance after consolidation (\"air gap\") was satisfactory. The final dimensions of the tubular targets have met the international specification.
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- 2018
45. Evaluation of the adsorptive removal of thiophene from a model gasoline using ZSM-35 impregnated with molybdenum
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Anne Michelle Garrido Pedrosa de Souza, Carlson Pereira de Souza, Iara Michelle Silva Correia, and Marcelo J. B. Souza
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ZSM-35 ,chemistry.chemical_element ,Sulfur ,Dessulfurização ,Flue-gas desulfurization ,chemistry.chemical_compound ,Adsorption ,chemistry ,Molybdenum ,Adsorção ,Thiophene ,General Earth and Planetary Sciences ,Thermal analysis ,Zeolite ,Organosulfur compounds ,General Environmental Science ,Nuclear chemistry - Abstract
The search for alternative processes for the removal of sulfur compounds in fuels is a constant, as environmental legislation around the world is becoming increasingly rigorous regarding reductions in the fraction of these compounds in fuels. This study evaluated the adsorptive capacity of zeolite ZSM-35 pure and impregnated with 2.5% and 5% molybdenum in the removal of the thiophene, organosulfur compound, of a model gasoline. The materials were prepared via wet impregnation and characterized by XRD, SEM, thermal analysis (TG/DTG). Adsorption kinetics were performed at temperatures of 303 K and 313 K in a batch system under agitation of 140 rpm for 12 hours. The kinetics of adsorption was evaluated by kinetic models of pseudo first order, pseudo second order, intraparticle diffusion and Elovich. The results showed that the increase in temperature and the concentration of molybdenum in the structure of the zeolite has an influence on the increase of the sulfur removal efficiency of the gasoline.
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- 2018
46. MoO3 supported in MCM-41 as heterogeneous catalyst reusable in the transesterification reaction
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ANDRADE, Maria Rosiane de Almeida., SOUSA, Bianca Viana de., ARAÚJO, Antônio Carlos Brandão de., and SILVA, Sidiney Kleber da.
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Molibdênio ,Molybdenum ,Peneira Molecular ,Molecular Sieve ,Biodiesel - Abstract
Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-10-19T12:37:38Z No. of bitstreams: 1 MARIA ROSIANE DE ALMEIDA ANDRADE - DISSERTAÇÃO (PPGEQ) 2017.pdf: 4020246 bytes, checksum: 96bceac541ee13322a3c142ca97018a6 (MD5) Made available in DSpace on 2018-10-19T12:37:38Z (GMT). No. of bitstreams: 1 MARIA ROSIANE DE ALMEIDA ANDRADE - DISSERTAÇÃO (PPGEQ) 2017.pdf: 4020246 bytes, checksum: 96bceac541ee13322a3c142ca97018a6 (MD5) Previous issue date: 2017-10-26 Capes A diminuição das reservas de combustíveis fósseis devido a grande demanda por energia e as alterações climáticas causadas pela emissão de gases do efeito estufa têm incentivado o desenvolvimento de novas fontes de energia, como o biodiesel. O biodiesel é um combustível biodegradável derivado de fontes renováveis, que pode ser produzido a partir de óleos vegetais, resíduos de óleos e gorduras animais. A principal rota de produção do biodiesel é a transesterificação metílica de triglicerídeos na presença de um catalisador básico homogêneo, mas este tipo de catalisador produz sabão e não é recuperado. Nesse sentido, estudos têm sidos desenvolvidos para produzir um catalisador heterogêneo capaz de obter elevadas conversões em ésteres e que seja facilmente recuperado e reutilizado. Dentre os catalisadores heterogêneos destacam-se os catalisadores de molibdênio devido a sua acidez de Lewis e Brønsted-Lowry, suportados em sílicas mesoporosas, como a peneira molecular MCM-41 que apresenta alta estabilidade térmica, elevada área superficial, grande volume de poros e distribuição de mesoporos ordenados que possibilitam a incorporação de metais em sua estrutura. Dessa forma o objetivo do presente trabalho é sintetizar o catalisador MoO3/MCM-41 e avaliar seu potencial catalítico na reação de transesterificação metílica do óleo de soja e testar sua atividade no seu reprocessamento. Para isso, inicialmente a peneira molecular MCM-41 foi obtida por um processo hidrotérmico a 30 °C por 24 h, utilizando o ortossilicato de tetraetila (TEOS), o brometo de cetiltrimetilamônio (CTABr), o hidróxido de amônio (NH4OH) e a água, e em seguida, passou por um processo de ativação por calcinação para remoção do direcionador estrutural. Posteriormente, foi incorporado na estrutura da MCM-41 o precursor heptamolibdato de amônio, por saturação de volume de poro, nas porcentagens (em massa) de 10, 20, 30, 40 e 45 %. A obtenção do MoO3 sob a peneira molecular MCM-41 se deu através do processo de ativação por calcinação. A partir dos resultados obtidos nos difratogramas de raios X foi possível confirmar a formação da peneira molecular MCM-41, bem como identificar os picos referentes ao MoO3. Os óleos obtidos nas reações de transesterificação apresentaram densidade e viscosidade dentro dos padrões estabelecidos pela resolução da Agencia Nacional de Petróleo, Gás Natural e Biocombustíveis (ANP) N° 51 de 25/11/2015, porém o índice de acidez não ficou dentro do limite máximo permissível e apenas os catalisadores com 10, 20 e 30 % de MoO3 conseguiram converter ao valor mínimo de ésteres. Os catalisadores de 30, 40 e 45% de trióxido de molibdênio apresentaram uma boa estabilidade catalítica nos dois ciclos de reuso, com uma redução máxima da atividade catalítica de 2,38%. Os óleos obtidos com a reutilização destes catalisadores apresentaram densidade e viscosidade dentro dos limites estabelecidos pela ANP. The decline in fossil fuel reserves due to high demand for energy and climate change caused by greenhouse gas emissions has encouraged the development of new energy sources such as biodiesel. Biodiesel is a biodegradable fuel derived from renewable sources, which can be produced from vegetable oils, waste oils and animal fats. The main production route of biodiesel is the methyl transesterification of triglycerides in the presence of a homogeneous basic catalyst, but this type of catalyst produce soap and are not recovered. In this sense, studies have been developed to produce a heterogeneous catalyst capable of obtaining high conversions into esters and that is easily recovered and reused. Among the heterogeneous catalysts, there is one that stands out the molybdenum catalysts due to their acidity of Lewis and Brønsted-Lowry, supported in mesoporous silicas, such as the MCM-41 molecular sieve, which presents high thermal stability, high surface area, large pore volume and distribution of ordered mesopores that allow the incorporation of metals in its structure. Thus the objective of the present work is to synthesize the MoO3/MCM-41 catalyst and to evaluate its catalytic potential in the reaction of methyl transesterification of soybean oil and to test its activity in its reprocessing. For this purpose, the molecular sieve MCM-41 was initially obtained by a hydrothermal process at 30 °C for 24 hours using tetraethyl orthosilicate (TEOS), cetyltrimethylammonium bromide (CTABr), ammonium hydroxide (NH4OH) and water and then passed by a calcination activation process to remove the structural driver. Subsequently, the ammonium heptamolybdate precursor was incorporated into the MCM-41 structure by pore volume saturation, in the percentages (in mass) of 10, 20, 30, 40 and 45%. The MoO3 under the MCM-41 molecular sieve was obtained by the calcination activation process. From the results obtained in the X-ray diffractograms it was possible to confirm the formation of the molecular sieve MCM-41, as well as to identify the peaks related to MoO3. The oils obtained in the transesterification reactions presented density and viscosity within the standards established by the Resolution of the National Agency of Petroleum Natural Gas and Biofuels. (ANP) N°. 51 of 11/25/2015, but the acidity index was not within the maximum allowable limit and only the Catalysts with 10, 20 and 30% MoO3 were able to convert to the minimum value of esters. The catalysts of 30, 40 and 45% of molybdenum trioxide showed good catalytic stability in the two cycles of reuse, with a maximum reduction of catalytic activity of 2.38%. The oils obtained with the reuse of these catalysts showed density and viscosity within the limits established by the ANP.
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- 2017
47. Uma investigação preliminar da dessulfurização oxidativa do óleo diesel comercial
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Aurélio Antônio Martins de Melo Santos, Lidiane Faria Santos, and Antonio Marcos de Oliveira Siqueira
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Molibdênio ,Materials science ,Catalisadores ,Vanádio ,chemistry.chemical_element ,Vanadium ,Diesel engine ,Sulfur ,Dessulfurização ,Catalysis ,Flue-gas desulfurization ,Solvent ,chemistry.chemical_compound ,chemistry ,Chemical engineering ,Molybdenum ,Enxofre ,Hydrogen peroxide - Abstract
The oxidative desulphurization is considerate one of the most promising methods to remove sulphurous compounds of fossil fuels, because it’s a process that can be realized under smooth conditions, ambient temperature and atmospheric pressure. The desulfurization process makes rusty compounds, where the sulfur goes from a divalent state to a hexavalent state, from this your extraction becomes possible using a solvent, for example the acetonitrile. The most used oxidant in this process is the hydrogen peroxide, having advantages, as your capacity of oxidize some compounds directly, thermal stability and the absence of problems with the mass transfer. The solid catalysts for the oxidative desulfurization are made with a base of transition metals. The molybdenum it’s a transition metal and your oxides can be used in great technologic application. The vanadium has a lot of applications as oxidative catalyst in chemical industries and also the environmental industries too. The reactions were carried out with 6 samples at a temperature of 60oC and 24°C ambient temperature, with and without catalysts, in order to analyze the efficiency of the process at different temperatures. The analyzes of the physico-chemical properties are of great importance to analyze possible changes because of the reactions. The proposed method to quantify the sulfur content was made, but because of the unsatisfying precipitation of the sulfurous compounds your efficiency could not be calculated. The oxidative desulfurization was found to be a method that does not affect the physico-chemical properties of the diesel engine, both the density and the viscosity remained in the pattern in all samples except when it was used in the MoO3 as catalyst, which caused an increase in its acidity level.
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- 2017
48. Preparation and application of the catalysts (8% MoO3 / VD, 8% MoO3 / NaMOR and 8% MoO3 / HMOR) in the reaction of methyl transesterification of soybean oil for biodiesel production
- Author
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LIMA, Erivaldo Genuíno., RODRIGUES, Meiry Glaúcia Freire., BARBOSA, Antonielly dos Santos., VASCONCELOS, Luiz Gonzaga Sales., SILVA JUNIOR, Heleno Bispo da., CLERICUZI, Genaro Zenaide., and SILVA, Sidinei Kleber da.
- Subjects
Molibdênio ,Termogravimetria ,Molybdenum ,Ciências ,Argila ,Clay ,Mordenita ,Biodiesel ,Engenharia Química ,Mordenite - Abstract
Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-03-27T21:15:45Z No. of bitstreams: 1 ERIVALDO GENUÍNO LIMA - TESE (PPGEQ) 2017.pdf: 3180376 bytes, checksum: d01c9d5a44e6812cfd719a5ce7cab9e6 (MD5) Made available in DSpace on 2018-03-27T21:15:45Z (GMT). No. of bitstreams: 1 ERIVALDO GENUÍNO LIMA - TESE (PPGEQ) 2017.pdf: 3180376 bytes, checksum: d01c9d5a44e6812cfd719a5ce7cab9e6 (MD5) Previous issue date: 2017-03-06 Capes O trabalho teve como objetivo preparar um grupo de catalisadores heterogêneos e avaliá-los na reação de transesterificação do óleo de soja com metanol para produzir biodiesel. O método hidrotérmico em condições estáticas foi utilizado para sintetizar a zeólita mordenita sódica com composição molar 6Na2O: Al2O3: 30SiO2: 780H2O. A deposição do óxido de molibdênio foi realizada pelo método de impregnação por via úmida. Os catalisadores (VD, 8%MoO3/VD, NaMOR, 8%MoO3/NaMOR, HMOR e 8%MoO3/HMOR) foram caracterizados por DRX, FRX-ED, MEV, Adsorção física de N2, FTIR e TPD-NH3. A reação de transesterificação do óleo de soja foi conduzida em reator batelada sem agitação, durante tempos diferentes de reação (1, 2, 3, 4, 6, 12 e 24 horas) a 200°C, utilizando uma relação soja/metanol de 1:12 e 5% de catalisador. O biodiesel foi caracterizado a partir da viscosidade cinemática, análise termogravimétrica, massa específica e índice de acidez. Os êxitos das sínteses das zeólitas mordenitas (NaMOR e HMOR) foram evidenciados pelas técnicas de DRX, FRX-ED e adsorção física de N2. Os padrões de difração de raios X da argila verde dura (VD) apresentaram picos característicos da estrutura que pertence ao grupo das esmectitas. Observou-se que a adição do molibidênio às amostras (NaMOR e HMOR) promove a redução na área superficial específica. Pela análise de Dessorção termoprogramada de NH3 os catalisadores apresentaram caracteristicas ácidas distintas, no caso dos catalisadores VD e 8%MoO3/VD apresentaram maior concentração de sítios ácidos fortes e uma pequena quantidade de sítios ácidos fracos, os catalisadores NaMOR e MoO3/NaMOR exibiram sítios de natureza fracos e médios e nos catalisados HMOR e MoO3/HMOR apresentaram picos em duas faixas de temperaturas com sítios ácidos fracos e fortes, podendo ser característicos de Brönsted e/ou Lewis. Os valores de viscosidade cinemática que mais se aproximaram da faixa exigida pela norma 45/2014 da Agência Nacional de Petróleo, Gás Natural e Biocombustíveis (ANP), foram com os tempos reacionais de 12 e 24 horas e catalisadores (8%MoO3/VD, 8%MoO3/NaMOR e 8%MoO3/HMOR). Na análise termogravimétrica dos biodieseis produzidos com 12 e 24 horas de reação, constatou-se a presença de duas regiões de perdas de massa, referente à volatilização dos ésteres metílicos e triglicerídeos não convertidos. Nos testes de massa específica e índice de acidez somente os catalisadores (8%MoO3/VD, 8%MoO3/NaMOR e 8%MoO3/HMOR) atenderam as especificações exigidas pela Agência Nacional de Petróleo, Gás Natural e Biocombustíveis (ANP). The objective of the work was to prepare a group of heterogeneous catalysts and to evaluate them in the reaction of transesterification of soybean oil with methanol to produce biodiesel. The hydrothermal method under static conditions was used to synthesize the sodium mordenite zeolite with molar composition 6Na2O: Al2O3: 30SiO2: 780H2O. The deposition of molybdenum oxide was carried out by the wet impregnation method. The catalysts (VD, 8% MoO3/VD, NaMOR, 8% MoO3/NaMOR, HMOR and 8% MoO3/HMOR) were characterized by DRX, FRX-ED, SEM, physical adsorption of N2, FTIR and TPD-NH3. The transesterification reaction of the soybean oil was conducted in a batch reactor without stirring during different reaction times (1, 2, 3, 4, 6, 12 and 24 hours) at 200 °C using a soy/methanol ratio of 1:12 and 5% catalyst. Biodiesel was characterized by kinematic viscosity, thermogravimetric analysis, specific mass and acidity index. The successes of the mordenite zeolite syntheses (NaMOR and HMOR) were evidenced by the XRD, FRX-ED and N2 physical adsorption techniques. The X-ray diffraction patterns of the hard green clay (VD) showed characteristic peaks of the structure that belong to the group of smectites. It was observed that the addition of molybdenum to the samples (NaMor and HMOR) promotes the reduction in the specific surface area. In the case of the catalysts VD and 8% MoO3/VD presented higher concentration of strong acid sites and a small amount of weak acidic sites, the NaMOR and MoO3/NaMOR catalysts exhibited nature And weak and medium sites and HMOR and MoO3/HMOR catalysts showed peaks at two temperature ranges with weak and strong acid sites, which may be characteristic of Brönsted and / or Lewis. The kinematic viscosity values that most approached the range required by the 45/2014 standard of the National Agency of Petroleum, Natural Gas and Biofuels (ANP) were with reaction times of 12 and 24 hours and catalysts (8% MoO3/VD, 8% MoO3/NaMOR and 8% MoO3/HMOR). In the thermogravimetric analysis of the biodiesel produced with 12 and 24 hours of reaction, it was verified the presence of two regions of mass loss, related to the volatilization of the methyl esters and unconverted triglycerides. In the tests of specific mass and acidity index only the catalysts (8% MoO3/VD, 8% MoO3/ NaMOR and 8% MoO3/HMOR) met the specifications required by the National Agency of Petroleum, Natural Gas and Biofuels (ANP).
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- 2017
49. Produção de biodiesel a partir da transesterificação do óleo de soja utilizando o catalisador MOO3/CEO2/MCM-41
- Author
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BARROS, Thiago Rodrigo Barbosa., SOUSA, Bianca Viana de., ARAÚJO, Antônio Carlos Brandão de., ALVES, José Jailson Nicacio., and ALMEIDA, Marcello Maia de.
- Subjects
Molibdênio ,Cério ,Molybdenum ,Peneira molecular ,Produção de biodiesel ,Production of biodiesel ,Cerium ,Biocombustível ,Tecnologia Química ,Biofuel ,MOO3 / CEO2 / MCM-41 catalyst ,Molecular sieve ,Óleo de soja ,catalisador MOO3/CEO2/MCM-41 ,Soy oil ,Engenharia Química - Abstract
Submitted by Emanuel Varela Cardoso (emanuel.varela@ufcg.edu.br) on 2018-08-23T19:44:24Z No. of bitstreams: 1 THIAGO RODRIGO BARBOSA BARROS – DISSERTAÇÃO (PPGEQ) 2017.pdf: 2174476 bytes, checksum: 3268fd475d20f6eff1be072f2e7fa4e3 (MD5) Made available in DSpace on 2018-08-23T19:44:24Z (GMT). No. of bitstreams: 1 THIAGO RODRIGO BARBOSA BARROS – DISSERTAÇÃO (PPGEQ) 2017.pdf: 2174476 bytes, checksum: 3268fd475d20f6eff1be072f2e7fa4e3 (MD5) Previous issue date: 2017-02-20 Capes Biodiesel, que é produzido a partir de óleos vegetais ou gorduras animais através da reação de transesterificação com álcool é um excelente substituto para o diesel de petróleo por ser um combustível biodegradável derivado de fontes renováveis. A peneira molecular MCM-41 apresenta potencial para processamento de ácidos graxos visando a produção de biodiesel, por controle da composição química e por tratamentos químicos posterior a sua síntese. A inserção de óxidos metálicos pode proporcionar um aumento no desempenho catalítico da peneira molecular, possibilitando a preparação de catalisadores com maior atividade, seletividade e estabilidade térmica. O presente trabalho tem como objetivo principal a obtenção de biodiesel a partir da reação de transesterificação do óleo de soja utilizando o catalisador MoO3/25CeO2/MCM-41. Para tal afinidade, a peneira molecular foi preparada partindo-se de um gel com a seguinte composição molar da mistura reacional: 1SiO2 : 0,30 CTABr : 11 NH3 : 144 H2O. A incorporação do cério e molibdênio (em peso) no suporte MCM-41 foi por via seca. Através dos difratogramas foi possível identificar os picos característicos da peneira molecular MCM-41, como também as fases dos óxidos de cério e molibdênio na estrutura da peneira molecular, confirmando os processos de impregnação. Por meio da isoterma de adsorção de nitrogênio a peneira molecular apresentou uma área superficial SBET de 1072 m2/g e isoterma do tipo IV característica de materiais mesoporosos. O catalisador contendo 15% em peso de molibdênio e 25% em peso de cério atingiu a maior conversão em éster metílico em torno de 93% como também densidade de 0.8832 g/cm3, viscosidade cinemática 4,044 mm2/s e acidez de 0,49 mg KOH/g. Biodiesel, which is produced from vegetable oils or animal fats by transesterification reaction with alcohol, is an excellent substitute for diesel oil being a biodegradable fuel derived from renewable. The molecular sieve MCM-41 has the potential to process fatty acids aiming biodiesel production, by controlling the chemical composition and subsequent chemical treatments to their synthesis. The inclusion of metallic oxides can provide an increase in catalytic performance of the molecular sieve, allowing th e preparation of catalysts with higher activity, selectivity and thermal stability. This study aims to obtain biodiesel from the transesterification reaction of soybean oil using the catalyst MoO3/25CeO2/MCM-41. To this affinity, the molecular sieve was prepared starting with a gel with the following molar composition of the reaction mixture: 1SiO2 : 0,30 CTABr : 11 NH3 : 144 H2O. The incorporation of cerium and molybdenum (by weight) in the MCM-41 was supported by dry. Through the XRD patterns it was possible to identify the peaks characteristic of MCM-41 molecular sieve, as well as phases of cerium and molybdenum oxides in the molecular sieve structure, confirming the impregnation process. By means of the nitrogen adsorption isotherm molecular sieve had a surface area SBET de 1072 m2/g and isotherm type IV characteristic of mesoporous materials. The catalyst containing 15% by weight molybdenum and 25% by weight cerium reached the highest methyl ester conversion around 93% as well as density of 0.8832 g/cm3, kinematic viscosity 4,044 mm2/s and acidity of 0,49 mg KOH/g
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- 2017
50. Productivity and mineral composition of common bean in response to fertilization with molybdenum and nickel
- Author
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Fábio Cunha Coelho, Otacílio José Passos Rangel, Geraldo de Amaral Gravina, Wanderson Souza Rabello, José Francisco Lopes, and Henrique Duarte Vieira
- Subjects
0106 biological sciences ,Materials science ,lcsh:Biotechnology ,Randomized block design ,chemistry.chemical_element ,01 natural sciences ,Human fertilization ,Dry weight ,lcsh:TP248.13-248.65 ,Phaseolus vulgaris L ,adubação foliar ,micronutrient ,lcsh:Agriculture (General) ,General Veterinary ,Acrisol ,micronutriente ,foliar fertilization ,04 agricultural and veterinary sciences ,lcsh:S1-972 ,Horticulture ,Nickel ,Point of delivery ,chemistry ,Molybdenum ,Shoot ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,General Agricultural and Biological Sciences ,010606 plant biology & botany - Abstract
RESUMO Níquel e molibdênio são micronutrientes essenciais que apresentam a capacidade de alterar o crescimento e o desenvolvimento do feijoeiro. O objetivo deste trabalho foi avaliar a produtividade, o crescimento e a composição mineral do feijão Ouro Vermelho em resposta às adubações com molibdênio (Mo) e níquel (Ni). O experimento foi conduzido a campo em Argissolo Acinzentado distrófico, no arranjo fatorial 5 x 2, referente a cinco doses de Ni (0; 15; 30; 45 e 60 g ha-1) e duas de Mo (0 e 80 g ha-1), no delineamento em blocos casualizados, com quatro repetições. A aplicação foliar de Ni e Mo foi feita aos 25 dias após a semeadura, por meio de um pulverizador manual. As características avaliadas foram: estande final, altura, produtividade, número de vagens por planta, número de sementes por vagem, massa de 100 sementes e os teores de N, P, K, Fe, Mo, e Ni. Verificou-se que a adubação molíbdica aumentou o teor de N na folha, reduziu o teor de Fe na semente e, em doses elevadas de Ni, reduziu o teor de Ni nas sementes. As doses de Ni, sem aplicação de Mo, aumentaram o teor de N na folha e, na presença do Mo, aumentaram o teor de Fe na semente. Houve aumento do número de grãos por vagem, com a aplicação de Ni, e da massa seca da parte aérea, com a adubação molíbdica. As adubações com 80 g ha-1 de Mo e 60 g ha-1 de Ni aumentaram em 12,71 e 27,5%, respectivamente, a produtividade do feijoeiro. ABSTRACT Nickel and molybdenum are essential micronutrients that have the ability to affect the growth and development of the bean. In this sense, the objective of this research was to assess the productivity, the growth and the mineral composition of 'Ouro Vermelho' bean in response to fertilization with molybdenum (Mo) and nickel (Ni). The field work was conducted at "Instituto Federal de Educação Ciência e Tecnologia do Espírito Santo (IFES/Alegre-ES)" in argisoil gray dystrophic haplic acrisol. The experiment was performed in 5 x 2 factorial with 5 doses of Ni (0; 15; 30; 45 and 60 g ha-1) and Mo (0 and 80 g ha-1) in a randomized block design, repeated four times. The foliar application of Ni and Mo was done 25 days after the seeding by means hand sprayer. The characteristics evaluated were: final stand, height, yield, number of pods per plant, number of seeds per pod, weight of 100 seeds and the contents of N, P, K, Fe, Mo, and Ni. Following this could be verified that the molybdenum fertilization increased the content of N within leaf, decreased the content of Fe within seed, and furthermore in case of high dose of Ni the content of Ni within seeds was decreased. The doses of Ni increased the content of N within the leaf, and also when the molybdenum is added the content of Fe within the seeds increased. The number of beans per pod increased after the application of Ni and dry weight of shoots with molybdenum fertilization. The fertilization with 80 g ha-1 of Mo and 60 g ha-1 with Ni increased in 12,71% and 29,69%, respectively, the productivity of bean.
- Published
- 2016
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