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(Ph3P)AuCl was discovered to be a powerful catalyst in the homocoupling of arylboronic acids and potassium aryltrifluoroborates for the synthesis of symmetrical biaryls. The reactions take place under benchtop reaction conditions in 96% EtOH at temperatures between rt and 50 °C with no exclusion of air or humidity, in the presence of F-TEDA (Selectfluor™) as an oxidant. The procedure is very functional group tolerant, and affords the corresponding biaryls in high yields with large substrate scope (26 examples). Ministry of Science and Education, Spain (PID2021–124419NB-I00) 4.6 Q2 JCR 2022 0.761 Q2 SJR 2022 No data IDR 2021 UEM

Introducción: La técnica incremental es un método para realizar restauraciones directas en resinas, que tiene como fin disminuir el factor de contracción, el cual genera consecuencias en la longevidad de la restauración. Objetivos: Determinar el nivel de conocimiento en la técnica incremental en resina en los estudiantes de Odontología de la Universidad Santo Tomás de Bucaramanga y evaluar su asociación con factores sociodemográficos Materiales y métodos: Se realizó un estudio observacional, analítico de corte transversal, se evaluaron 180 estudiantes del programa odontología, a los cuales se le aplico un cuestionario virtual de 17 preguntas, el instrumento de medición fue certificado por expertos en el área de rehabilitación oral. Resultados: Se encontró que 87.78% de estudiantes presentan un nivel de conocimiento regular, el 0.56% presento un nivel de conocimiento bueno y el 11.66% un nivel de conocimiento malo. Se observa que en el nivel de conocimiento de la técnica incremental en resina según la clínica predomina el conocimiento regular con un (23.42%) clínica I, un (24.05%) clínica II, el (26.58%) clínica III. (23.42%) en la clínica IV y un (2.53%) en la clínica V Conclusión: el nivel de conocimiento sobre la técnica incremental en resinas que obtuvo mayor porcentaje fue regular. Introduction: The incremental technique is a method to perform direct restorations in resins, which aims to reduce the contraction factor, which generates consequences in the longevity of the restoration. Objectives: To determine the level of knowledge in the incremental technique in resin in the Dentistry students of the Santo Tomás de Bucaramanga University and to evaluate its association with sociodemographic factors. Materials and methods: An observational, analytical, cross-sectional study was carried out, evaluating 180 students of the dentistry program, to whom a virtual questionnaire of 17 questions was applied, the measurement instrument was certified by experts in the area of oral rehabilitation. Results: It was found that 87.78% of students present a regular level of knowledge, 0.56% present a good level of knowledge and 11.66% a bad level of knowledge. It is observed that in the level of knowledge of the incremental technique in resin according to the clinic, regular knowledge predominates with (23.42%) clinic I, (24.05%) clinic II, and (26.58%) clinic III. (23.42%) in clinic IV and (2.53%) in clinic V Conclusion: the level of knowledge about the incremental technique in resins in students obtained a higher percentage was regular. Odontólogo http://www.ustabuca.edu.co/ustabmanga/presentacion Pregrado

RESUMEN Se llevó a cabo la aplicación del método de los Multiplicadores de Lagrange en la optimización de la cinética de cloración con conversión al 60% de la reacción entre el ácido esteárico y el cloro en presencia del peróxido de benzoilo, con la finalidad de obtener un valor máximo de la reacción, que pueda optimizar los recursos del laboratorista, al realizar el experimento. Esto se realizó gracias a la obtención de una ecuación de regresión no lineal del tipo exponencial, mediante el método de los mínimos cuadrados. Luego se procedió a calcular una función que encierre los valores experimentales, que en este caso fue una ecuación elíptica y luego aplicar el método de los Multiplicadores de Lagrange, con una restricción, para determinar el valor extremo local. Posteriormente se calcula la derivada direccional en el punto extremo obtenido, para demostrar que corresponde a un máximo local. El método de los Multiplicadores de Lagrange sirve para determinar puntos máximos o mínimos de funciones multivariables, como las que se observan en la cinética química. Abstract The method of Lagrange Multipliers was applied in the optimization of chlorination kinetics with a 60% conversion in the reaction of stearic acid with chlorine in the presence of benzoyl peroxide in order to obtain a maximum reaction value that would optimize the lab technician’s resources at the time of conducting the experiment. This was achieved by obtaining a multivariate, exponential, nonlinear regression equation by the method of least squares. Afterward, a function that enclosed the experimental values was calculated, which resulted in an elliptic equation. Later, the Lagrange multipliers method was applied with a restriction to determine the local extreme value. Subsequently, the directional derivative was calculated in the obtained extreme point to show that it corresponds to a local maximum. The Lagrange multiplier method is used to determine the maximum and minimum points of multivariate functions, such as those found in chemical kinetics.&nbsp

Orientador: Carol Hollingworth Collins Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Quimica Mestrado Química Analítica Mestre em Química

Neste trabalho é apresentado um estudo da aplicação de catalisadores ácidos na produção de ésteres etílicos a partir da blenda de sebo bovino e óleo de fritura, tendo em vista que tais matérias-primas vêm se mostrando uma alternativa econômica e ecologicamente sustentável para a produção de biodiesel. O objetivo desta pesquisa é estudar qual catalisador: ácido sulfúrico e fosfórico promove maior rendimento da reação de transesterificação. Foi observado que a conversão de ácidos graxos em ésteres etílicos foi muito baixa para o ácido fosfórico inviabilizando, portanto, a produção do biodiesel com a utilização deste catalisador.

The effect of substituents on the acidity of benzoic acids and basicity of anilines has been organized in grids to demonstrate the inductive and resonance effects. The relation between structure and pKa is emphasized by a new educational process: the Search-Organize-Predict (SOP) procedure. El efecto de los sustituyentes en la acidez de ácidos benzoicos y la basicidad de anilinas ha sido organizado en cuadrículas para demostrar los efectos inductivos y de resonancia. Se hace énfasis en la relación entre la estructura y la pKa mediante un proceso didáctico nuevo: el procedimiento Buscar-Organizar-Predecir. UCR::Vicerrectoría de Investigación::Unidades de Investigación::Ciencias Básicas::Centro de Investigaciones en Productos Naturales (CIPRONA) UCR::Vicerrectoría de Docencia::Ingeniería::Facultad de Ingeniería::Escuela de Ingeniería Química

El presente texto tiene como objetivo abordar el tema de la acidez y basicidad de compuestos orgánicos, uno de los más importantes en la Química Orgánica, ya que muchas de las reacciones y procesos que ocurren tanto en dicha disciplina como en la Química de los seres vivos dependen de las propiedades ácido–base de los compuestos. No está demás aclarar que, en la vida cotidiana, muchas de las situaciones que se nos presentan pueden ser planteadas también desde esta propiedad de los compuestos., Facultad de Ciencias Exactas

Orientador: Gustavo Doubek Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Química Resumo: Motivados pela necessidade da diminuição de emissões de gases do efeito estufa, a substituição do sistema de combustão interna por baterias, tem recebido cada vez mis atenção. Nesse sentido, as baterias de íons de lítio têm se mostrado uma alternativa a melhor atrativa para a contrucao do motor eletrico, entretanto os bancos de baterias em veículos elétricos atuais ainda conferem uma autonomia limitada. No entanto, as baterias lítio-oxigênio vêm atraindo atenção da comunidade científica por apresentar em teoria uma densidade energética específica cerca de dez vezes maior do que as atuais baterias lítio-íon, chegando a ser comparável até à densidade energética dos combustíveis fósseis. Nesse cenário o presente trabalho de pesquisa visa avaliar o desempenho com e sem a funcionalização do plasma oxigênio em baterias de Li-O2, utilizando novos materiais baseado em nanotubos de carbono como cátodo. Nós relatamos que o tratamento ácido no eletrodo de nanotubo de carbono não degradou o cátodo e ainda melhorou a molhabilidade e a fase tripla reacional. Foi estudado o sistema bateria Li-O2 com DMSO/LiClO4 como eletrólito e o lítio metálico como o referência. O eletrodo com o tratamento ácido apresentou o melhor resultado de capacidade de descarga (2804 mAh g-1) quase 3 vezes maior que o material sem o tratamento (1062 mAhg-1). O ácido criou defeitos na estrutura do nanotubo, criando regiões mais reativas, com isso aumentando o valor de capacidade, porém o sistema provou ser não reversível. Ao limitar a capacidade de descarga para 500 mAh g-1, foi observada uma melhora na ciclagem, no entanto, o dispositivo não atingiu um número satisfatório de ciclos, e o sobrepotencial da carga aumentou ao longo dos ciclos. Com o intuito de investigar as razões para tais respostas várias caracterizações ex-situ foram realizadas, sendo notória a grande formação de Li2CO3, o que está de acordo com a baixa ciclabilidade do dispositivo. Esta formação de Li2CO3 também foi observada ao realizar um estudo ex-situ, variando o tempo de descarga. Nesta análise final foi possível verificar que o carbonato de lítio é continuamente formado ao longo da descarga, formando-se também entre os nanotubos de carbono que resultou na formação de uma camada sólida e contínua de produto de descarga, impossibilitando a ciclabilidade do dispositivo Abstract: Driven by the need for the reduction of greenhouse effect gas emissions, the replacement of the supply system of automotive vehicles of internal combustion by electric or hybrid has recently received considerable attention. On these terms the lithium-ion batteries arose as the best alternative, however the current technologies still grant limited autonomy to these vehicles. In the research field, the lithium-air batteries have been drawing efforts for showing a specific energy density around three times greater than the current batteries in such a way that it can be compared even to the fossil fuels energy density. In this scenario, the present work aims to evaluate the performance with and without the functionalization of oxygen plasma in Li-O2 batteries using new materials based on carbon nanotubes as cathode. We report a pretreatment with acid on the carbon nanotube that not degrade the cathode and improve the wettability and the reactional triple phase. This cathode perform in Li-O2 battery with DMSO/LiClO4 as the electrolyte, present the best discharge capacity result (2804 mAh g-1) almost 3x higher than as-grow (1062 mAhg-1). The acid created defects in the structure of the nanotube, creating more reactive regions, but the system proved to be non-reversible. By limiting the discharge capacity to 500mAh g-1, an improvement in the cycling was observed, however, the device did not reach a satisfactory number of cycles, and the charge overpotential increased over the cycles. In order to investigate several characterizations analyzes ex situ were performed, and it was notice a large formation of Li2CO3, which is in accordance with the low cyclability for the device. This Li2CO3 formation was also observed when performing an ex-situ study following the discharge of the battery for different times. In this final analysis it was possible to verify that the lithium carbonate is continuously formed along the discharge, forming also between the CNTs which resulted in the formation of a solid and continuous layer of the discharge product Mestrado Engenharia Química Mestre em Engenharia Química CAPES 33003017034P8

RESUMEN: La presente tesis doctoral pretende contribuir al avance en el conocimiento y al desarrollo tecnológico de la recuperación de materiales contenidos en corrientes residuales mediante la integración de fuentes de energías renovables con tecnologías de electro-membranas, haciendo incidencia tanto en los aspectos de viabilidad técnica como ambiental. Se ha tomado como caso de estudio la obtención de HCl y NaOH a partir de salmueras de desalación mediante la tecnología integrada electrodiálisis con membranas bipolares – solar fotovoltaica (EDBM-PV). La producción de ácidos y bases permitiría potencialmente, en función de la concentración y pureza alcanzadas, bien cubrir la demanda in-situ derivada de las operaciones de acondicionamiento de corrientes dentro de una desaladora, o bien la posibilidad de comercializar ambos productos. La mejora en la sostenibilidad ambiental de la planta desaladora vendría fundamentalmente de la integración de energía solar PV (reducción de cargas ambientales indirectas) y de la reducción del consumo externo de productos químicos. ABSTRACT: This doctoral thesis aims to contribute to the advancement in knowledge and technological development of the recovery of materials contained in waste streams by integrating renewable energy sources with electro-membrane technologies, making an impact on both technical and environmental feasibility aspects. It has been considered the obtaintion of HCl and NaOH from desalination brines using the integrated process of photovoltaic solar-electrodialysis with bipolar membranes (EDBM-PV) as a case study. The production of acids and bases would potentially allow, depending on the concentration and purity achieved, to meet the on-site demand derived from the operations of conditioning currents within a desalination plant, or the possibility of marketing both products. The improvement in the environmental sustainability of the desalination plant would come mainly from the integration of PV solar energy (reduction of indirect environmental burdens) and the reduction of external consumption of chemical products. Este trabajo ha sido financiado por el Ministerio de Economía y Competitividad del Gobierno de España a través del proyecto CTM2014-57833-R “Estrategias de Valorización de Salmueras” y por el Ministerio de Ciencia, Innovación y Universidades del Gobierno de España a través del proyecto CTM2017-87850-R “Tecnologías Ambientales Sostenibles para el Aprovechamiento Energético de Corrientes Residuales”.

Agricultural use is the main way of recycling sewage sludge. Besides providing nutrients and organic matter to crops and soils, it is an important alternative for recycling this residue. However, problems during the sewage treatment process may generate sludge batches with an acidic pH. Thus, it is essential to understand the consequences of using such sludge on soils and plants, and to explore ways to overcome this limitation. The objective of this study was to evaluate addition rates of anaerobic sewage sludge (ASS) with acidic compositions on the soil fertility and performance of lettuce plants. Additionally, a methodology for pH correction of ASS with acidic pH is proposed. An agronomic experiment was conducted in a greenhouse using seven addition rates of ASS (0.0, 0.25, 0.5, 1, 2, 4 and 8 g kg−1 in dry basis), treated with an additional step of disinfection (solarization), and applied in an Albaqualf soil cultivated with lettuce (Lactuca sativa). Soil and leaf chemical composition, as well as chlorophyll index and the dry matter of lettuce leaves were evaluated. Failures during the acidogenesis phase of the anaerobic digestion process were probably the cause of ASS acidification. Although this ASS increased soil fertility indicators and plant dry matter, it significantly reduced soil pH, thereby requiring a complementary assay to correct its pH up to 6.0, which was achieved through liming. Anaerobic sewage sludges with an acidic pH can be effectively used in agriculture after being dried and disinfected through solarization, followed by pH correction, avoiding negative impacts on soil chemical attributes and plant response. Made available in DSpace on 2020-12-10T09:04:53Z (GMT). No. of bitstreams: 1 1-s2.0-S0301479720311282-main.pdf: 4720207 bytes, checksum: b39e0e3c368a95e7db3b19e41c1fd924 (MD5) Previous issue date: 2020

"Azospirillum es una rizobacteria capaz de promover el crecimiento vegetal de diferentes cultivos de interés agronómico. Se conocen hasta ahora 21 especies, siendo la más estudiada Azospirillum brasilense. Se ha reportado el efecto del uso de la bacteria en cultivos de maíz, habiéndose determinado el mismo en parámetros como ser la altura de la planta y el contenido de clorofila, incluido un aumento de la cantidad de nitrógeno fijado de la atmósfera. De forma similar, en cultivos de soya y trigo, se ha reportado un beneficio significativo en el aumento del contenido de clorofila relacionado con el aumento en el rendimiento de grano por hectárea. El mecanismo principal por el cual Azospirillum mejora le crecimiento vegetal es la producción de fitohormonas, principalmente el ácido-3-indol acético (AIA), el cual es generado en la planta, pero en cantidades nanomolares, participando en diversas funciones. Se conoce que la vía principal a la producción de AIA es a través del aminoácido triptofáno (TRP) mediante cuatro rutas: 1) indol-3-acetonitrilo (IAN), 2) indol-3-acetamida (IAM) 3) ácido indol-3-pirúvico (IPyA) y 4) Triptamina (TAM). Gracias a diversos estudios se sabe que existe una ruta independiente de TRP, pero hasta el momento, no se conocen los metabolitos que intervienen en la ruta ni sus niveles de expresión, ni las circunstancias ambientales en las que se expresan."

Submitted by Ana Claudia dos Santos (ana.c.santos@unesp.br) on 2022-04-18T19:00:42Z No. of bitstreams: 1 ilovepdf_merged_organized Ana Claudia.pdf: 1150389 bytes, checksum: 97ad975f65e53de3aea6b6be87f90036 (MD5) Approved for entry into archive by Laudicélia Martins Arantes (lm.arantes@unesp.br) on 2022-04-18T19:42:43Z (GMT) No. of bitstreams: 1 santos_ac_me_jabo.pdf: 1150389 bytes, checksum: 97ad975f65e53de3aea6b6be87f90036 (MD5) Made available in DSpace on 2022-04-18T19:42:43Z (GMT). No. of bitstreams: 1 santos_ac_me_jabo.pdf: 1150389 bytes, checksum: 97ad975f65e53de3aea6b6be87f90036 (MD5) Previous issue date: 2019-09-11 Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) Bactérias promotoras de crescimento de plantas podem ser uma alternativa para a produção vegetal em problemas como aumento dos índices de produtividade, e diminuição dos impactos ambientais. As bactérias probióticas possuem diversas habilidades, dentre elas facilitar a digestão e a absorção de nutrientes, e fortalecer o sistema imunológico de homens e animais. Nesse sentido, o objetivo desse estudo foi avaliar se os micro-organismos probióticos podem trazer benefícios também as plantas, como incremento de nutrientes. Para isso, utilizou-se as culturas de milho e soja, onde foi inoculado bactérias probióticas isoladas do rúmen: Bacillus cereus, Lactobacillus acidophilus e Succinovibrio dextrinosolvens. Os testes in vitro mostraram que as bactérias foram capazes de fixar nitrogênio, solubilizar o fósforo, sintetizar ácido indolacético e amilase. Depois dos testes in vitro, os experimentos foram conduzidos em casa de vegetação em blocos casualizados com cinco tratamentos e seis repetições, sendo eles T1= Controle; T2= Bacillus cereus, T3= Lactobacillus acidophilus, T4= Succinovibrio dextrinosolvens, T5= Bacillus cereus + Lactobacillus acidophilus + Succinovibrio dextrinosolvens. A inoculação com S. dextrinosolvens proporcionou o aumento da massa seca de raiz em milho, enquanto que a aplicação individual com L. acidophilus e em conjunto com as demais bactérias, proporcionaram o aumento do teor fósforo nas raízes de milho. Nas plantas de soja, a inoculação com L. acidophylus promoveu o aumento da massa seca da parte aérea e da concentração de fósforo e nitrogênio, em comparação ao tratamento não inoculado. Este é o primeiro relato mostrando que a bactéria L. acidophilus e S. dextrinosolvens possuem potencial para serem utilizadas como bactérias promotoras de crescimento de plantas. Plant growth-promoting bacteria may be an alternative to crop production in problems such as increased yields and reduced environmental impacts. Probiotic bacteria have many abilities, including facilitating digestion and absorption of nutrients, and strengthening the immune system of humans and animals. In this sense, the objective of this study was to evaluate if probiotic microorganisms can also bring benefits to plants, such as nutrient increment. For this, corn and soybean cultures were used, where probiotic bacteria isolated from the rumen were inoculated: Bacillus cereus, Lactobacillus acidophilus and Succinovibrio dextrinosolvens. In vitro tests showed that bacteria were able to fix nitrogen, solubilize phosphorus, synthesize indolacetic acid and amylase. After in vitro tests, the experiments were conducted in a greenhouse in randomized blocks with five treatments and six replications, T1 = Control; T2 = Bacillus cereus, T3 = Lactobacillus acidophilus, T4 = Succinovibrio dextrinosolvens, T5 = Bacillus cereus + Lactobacillus acidophilus + Succinovibrio dextrinosolvens. The inoculation with S. dextrinosolvens increased the root dry mass in maize, while the individual application with L. acidophilus and together with the other bacteria, increased the phosphorus content in the corn roots. In soybean plants, inoculation with L. acidophylus promoted the increase of shoot dry mass and phosphorus and nitrogen concentration, compared to uninoculated treatment. This is the first report showing that L. acidophilus and S. dextrinosolvens have the potential to be used as plant growth promoting bacteria. CAPES

The physicochemical characteristics of honey vary according to bee species, climate, region, period of collection, processing and storage. In this context, this work aimed to perform a comparative study of the physicochemical characteristics of Melipona subnitida and M. fasciculata honey collected at different periods and regions of the State of Piauí, Brazil. Twenty-nine honey samples were collected and evaluated by principal component analysis from physicochemical analysis data. Twenty-two percent of the parameters analyzed differed between species. Evaluating the collection period, the honey of M. subnitida and M. fasciculata presented differences among themselves. The study revealed a similarity between the physicochemical parameters of the honey of the two species of bees, in addition, the time was one of the determining factors in the formation of clusters. Made available in DSpace on 2020-10-21T09:13:45Z (GMT). No. of bitstreams: 1 CharacterizationHoneyStinglessBeesFoodChemistry327.2020.pdf: 266107 bytes, checksum: 81756a9df4d1b66a427e3d89160cb901 (MD5) Previous issue date: 2020

Nopyl acetate is an artificial fragrance compound with a fruity odor of fresh wood which is not present in nature and it is used in the preparation of soaps, detergents, creams, lotions and perfumes. It is conventionally prepared by the carbonyl-ene reaction of β-pinene and paraformaldehyde with subsequent acetylation of the intermediary nopol with acetic anhydride. As the esterification reaction in the absence of a catalyst is slow and reversible and water is one of the by-products, a hydrothermal stable material is required as catalyst. There are few reports about the synthesis of nopyl acetate. It was reported that the reaction at 200 °C of β-pinene with paraformaldehyde in the presence of acetic anhydride produces nopyl acetate with a 60 % yield after 5 h. For nopol esterification with carboxylic chloride acids in triethanol amine and dichloromethane solution, nopyl acetate yields of 79 % (5 to 25 °C) were achieved. Nopyl acetate may be synthesized from acetic anhydride and sodium acetate, with 84 % yield (3 h, 90 ° C) after its separation and purification. It is possible to obtain yields of 98 % (150 °C, 1 h) by reacting nopol with acetic anhydride in the presence of toluene or chlorobenzene, removing the carboxylic acid by-product by azeotropic distillation. The synthesis of nopyl acetate with acetic anhydride in the presence of triethylamine and dimethylaminopyridine (DMAP) in dichloromethane as solvent at room temperature, with quantitative yields, has been reported. Using ammonium and cerium nitrate catalyst, (NH4)Ce(NO3)6 in CH2Cl2 as solvent at 40-50 °C, nopyl acetate is obtained with a 92 % yield. Costa et al. reported in 2016 the use of tungstophosphoric heteropoly acid H3PW12O40 (HPW) and its acidic Cs salt Cs2.5H0.5PW12O40 (CsPW) for the liquid phase acetylation of nopol. The reaction occurs at room temperature with low catalyst loadings and can be performed solvent-free with stoichiometric amounts of acetic anhydride providing excellent yields (100%). Recently, environmental and economic considerations have promoted innovation processes towards the use of cleaner technologies. Therefore, there is a great challenge of using heterogeneous catalysts that can perform under mild reaction conditions, for example at low temperatures and pressures, while avoiding the use of harmful substances such as amines and chlorinated compounds. Systems reported for the esterification of other alcohols could be considered as possible alternatives for the esterification of nopol. Tin modified mesoporous materials (MCM-41 and SBA-15) could be attractive alternatives with voluminous organic molecules like nopol. Ionic exchange resins like Amberlyst – 15, with functional group –SO3H, have been used in the esterification of primary alcohols with acetic acid. Sn-SBA-15 is an acid catalyst, with a mesoporous support that would avoid mobility restriction of reactants and products. Additionally, Sn-MCM-41 has been found to be a suitable mesoporous material for nopol production. The use of Sn supported on SiO2 is an economical option, as well as Amberlyst-15. p-toluenesulfonic acid (PTSA) has the potential to be used as a substitute for conventional acidic catalytic materials. It is characterized by the mildness of the reaction conditions, inexpensive chemical and the excellent functional group tolerance, allowing the formation of the corresponding esters in good to excellent yields. The objective of this research is to determine the most adequate catalyst and reaction conditions for nopyl acetate synthesis in order to achieve highest reaction rate. Sn-MCM-41, Sn-SBA-15 and Sn-SiO2 heterogeneous catalysts were synthesized by incipient wetness impregnation using SnCl2 • 2H2O as precursor at room temperature. Physicochemical properties of the materials were determined by surface area BET (Brunauer, Emmett and Teller), SEM (Scanning Electron Microscopy), AAS (Atomic Absorption Spectroscopy) of Sn, NH3-TPD (Ammonia Temperature Programmed Desorption), FTIR (Fourier-transform Infrared Spectroscopy), UV-vis (Ultraviolet–visible spectroscopy), Raman spectroscopy, XRD (X-ray Diffraction), and TGA (Thermal Gravimetric Analysis). Characterization of MCM-41 and SBA-15 materials verified that synthesized catalysts have ordered hexagonal mesostructures. The XRD patterns of Sn-SBA-15 and Sn-MCM- 41 were very similar to those of the supports. SEM micrographs indicated that SBA-15 and Sn-SBA-15 showed the characteristic morphology of SBA-15, represented in domains in the form of loops that are added to a microstructure similar to wheat. The N2 adsorption and desorption isotherms of the materials were type IV, which is typical of mesoporous materials. The BET areas of SBA-15 and Sn-SBA-15 were 531 and 471 m2/g respectively. Surface area of MCM-41 decreased from 596 to 576 m2/g by incorporating tin. SiO2 and Sn-SiO2 surface areas were 434 and 364 m2/g, respectively. TPD analysis established the presence of strong (1.42 mmol NH3/g cat), medium (0.08 mmol NH3/g cat) and weak acid sites (0.24 mmol NH3/g cat) in the materials. For kinetic tests with Amberlyst-15 and Sn-SBA-15, an average particle size of 58-76.5 μm and stirring speeds between 500 and 1000 rpm were used for guarantying the absence of diffusion effects for kinetic tests. Acetic acid and acetic anhydride were used as esterifying agents. In presence of n-hexane, nopyl acetate selectivity over Sn-SBA-15 was 15.2 % and Sn-MCM-41 displayed best ester selectivity (17.8 %) in toluene at a 2:1 acetic acid: alcohol molar ratio. Amberlyst-15 reaches 100 % nopol conversion in presence of toluene at acetic acid: alcohol ratios of 1:2, 1:1 and 2:1. Synthesis of nopyl acetate was satisfactory using homogeneous catalyst p-toluenesulfonic acid (p-TSA), achieving a selectivity of 45.6 % and a nopol conversion of 99.7 % compared to Amberlyst-15 with 9 % ester selectivity and 57.6 % alcohol conversion. Using acetic anhydride, Sn-SiO2 reaches 75 % nopol conversion at 60 min making it an active and selective material for nopyl acetate synthesis. Amberlyst-15 exhibited best and more stable catalytic activity and with Sn-SiO2 catalyst, best nopyl acetate selectivity was attained. Catalyst reusability was performed separating the material by decantation; washing it three times with acetone under continuous stirring and drying it in an oven at 80 °C overnight. This procedure was carried out before every reuse. The reusability tests were carried out with Amberlyst-15 that was the material that showed the highest nopol conversion, and it was found that the material loses catalytic activity in the fourth cycle, although leaching of the active species does not occur. The structural properties of Sn-SBA-15, the high catalytic performance and the economic viability of Sn-SiO2 make these materials potential to replace homogeneous acid catalysts in the nopol esterification reaction. Best nopyl acetate selectivity (100 %) is obtained over Sn-SiO2, achieving a 75 % nopol conversion at 60 min, with a 3:1 acetic anhydride: alcohol molar ratio in presence of toluene, 80 °C and 750 rpm. Using Amberlyst-15, nopyl acetate selectivity reaches 8.2 % and 65.8 % nopol conversion at reaction times 90-120 min, 6.1 mg/mL catalyst loading, 80 °C, 750 rpm, nopol/ toluene solution 0.25 M and a 2:1 acetic acid: alcohol molar ratio.

Um dos principais motivos que leva ao desenvolvimento de tecnologias para recuperação de petróleo é a alta porcentagem de óleo que permanece no reservatório após as recuperações primária e secundária, e estas não serem mais capazes de recuperá-lo. Nesse trabalho, foram utilizados sistemas microemulsionados e nanoemulsionados ácidos em processos de recuperação avançada. Os sistemas apresentam em sua composição: tensoativo, cotensoativo, querosene e solução ácida com diferentes concentrações. O tensoativo utilizado é comercial e de caráter não iônico. O ácido, por reagir com a rocha carbonática, tende a desobstruir os possíveis poros que ainda se apresentem fechados por determinadas partículas ou até mesmo formar novos canais, aumentando a permeabilidade da rocha. Os sistemas usados divergem entre si na concentração ácida da fase aquosa que compreende valores de 1,5%, 5%, 10% e 15% de HCl. As concentrações que compõem os sistemas foram escolhidas através do diagrama pseudoternário, os sistemas possuem 80% de fase aquosa, 2% de fase óleo, 12% de tensoativo e 6% de cotensoativo. Após escolhido um ponto no diagrama, os sistemas foram todos caracterizados por tensão superficial, viscosidade, capacidade corrosiva, c.m.c., diâmetro de partícula e cinética de reação do ácido com a rocha. Em seguida, foi estudada a eficiência de recuperação de cada sistema em um simulador de reservatório com temperatura e pressão controladas, onde apresentaram as seguintes porcentagens de óleo recuperado: 28%, 39%, 44% e 48% para os sistemas com 1,5%, 5%, 10% e 15% de HCl, respectivamente. Desse modo, concluiu-se que quanto maior a concentração do ácido, mais ele tende a aumentar a permeabilidade da rocha e aumentar a eficiência de recuperação. Por fim, foi obtida uma nanoemulsão a partir da microemulsão mais eficiente (sistema 4) que foi caracterizada da mesma forma que os demais sistemas, e aplicada na recuperação avançada, apresentando 84% de óleo recuperado. Conclui-se que as microemulsões e nanoemulsões ácidas são sistemas eficientes quando aplicadas na recuperação avançada com a vantagem de permear a rocha de forma mais homogênea e diminuir a corrosão dos equipamentos em valores próximos a 60%, constituindo-se uma alternativa para aplicação na área. One of the main reasons that leads to the development of technologies for the oil recovery is the high remaining oil percentage in the well after primary and secondary recovery, and these are no longer able to recover it. In this work, microemulsion systems and acid nanoemulsions will be used in advanced recovery processes. The systems present in its composition: surfactant, co-surfactant, kerosene and acid solution with different concentrations. The used surfactant is commercial and of noionic character. The acid, when reacting with the carbonated rock, tends to open the possible pores that still are closed for certain particles or until forming new canals, increasing the permeability of the rock. The used systems had differed only in the acid concentration in aqueous phase that contained 1.5% of HCl, 5%, 10% and 15%. The concentrations that compose the systems were chosen through the mounted ternary diagram, the systems contain 80% of aqueous phase, 2% of oil phase, 12% of surfactant and 6% of cosurfactant. After to have definitive this point, all the systems were characterized by its superficial tension, viscosity, corrosive capacity, c.m.c., diameter of the particle and speed of reaction between acid and rock. After the this, the efficiency of the recovery of each system in a simulator of the reservoir with controlled temperature and the pressure had been measured, them had presented the following recovered oil percentages: 28%, 39%, 44% and 48% for the systems with 1,5%, 5%, 10% and 15% of HCl, respectively. In this manner, was concluded that how much bigger the concentration of the acid one, plus it tends to increase the permeability of the rock and to increase the recovery efficiency. Finally, was made a nanoemulsion of the microemulsion system more efficient (system 4), it was characterized in the same way that too much systems, presenting 84% of recovered oil. It was concluded that acidic microemulsion and nanoemulsion are afficient systems when applied in the advanced recovery with the advantage of permeating the rock becoming a more homogeneous and reducting the corrosion of the equipaments in values up to 60%, constituting an alternative for application in the area.

There is no clear consensus on the management of accidental ingestion of caustic substances in paediatrics. The aim of this study was to determine the profile of the paediatric population treated due to caustic ingestion in a Healthcare Centre. Patients and method: A descriptive study was conducted on patients treated for the ingestion of caustic substances in our hospital during the period 2008-2011. Results: A total of 12 patients were treated, with a mean age of 3.8 years (1-13 years), with the majority males (58.8%). An alkaline product was ingested by 58.3%, and an acid by 41.6%. The majority (58.3%) did not refer to symptoms and the remainder referred to vomiting (33.3%), odynophagia (16.6%), haematemesis (8.3%), hyper-salivation (8.3%) and shortness of breath (8.3%). Oral cavity lesions were observed in 75% of cases. All, except one, were accidental. An endoscopy was performed on all of them (100%) between 12 and 24 hours post-ingestion, with pathological findings in 41.6%. In the group that ingested an alkali, 2 (16.6%) patients had lesions, one a grade 2B and one a grade 3 oesophagitis. In the acid ingestion group, 4 (33.3%) patients had lesions; one grade 1-2A oesophagitis, two acute non-erosive gastritis, and one acute haemorrhagic gastritis. A follow-up endoscopy was performed depending on the previous endoscopic findings. Only two patients presented with complications. Conclusions: Emphasis is placed on the endoscopic evaluation in the first 24 hours of deliberate asymptomatic ingestions, as well as a strict follow-up in those that ingested acids, due to delayed associated lesions. Yes Introdución: La ingesta accidental de cáusticos en pediatría no dispone de un consenso claro de actuación. El objetivo de este estudio fue caracterizar la población pediátrica atendida por ingesta de cáusticos en un centro asistencial. Pacientes y método: Estudio descriptivo de los pacientes atendidos en nuestro hospital por la ingesta de cáusticos durante el período 2008-2011. Resultados: Se atendieron 12 pacientes, edad media de 3,8 años (1-13 años). Predominio de varones (58,8%). Un 58,3% ingirió producto alcalino y un 41,6% ácido. El 58,3% no refería sintomatología, el resto refirió vómitos (33,3%), odinofagia (16,6%), hematemesis (8,3%), sialorrea (8,3%) y dificultad respiratoria (8,3%). El 75% presentaron lesiones en la cavidad oral. Todos, salvo un caso, fueron accidentales. Se realizó endoscopia al 100% entre las 12 y 24 h postingesta con hallazgos patológicos en un 41,6%. En el grupo ingesta de álcalis 2 pacientes presentaron lesiones (16,6%): una esofagitis grado 2B y una grado 3. En el grupo ingesta de ácidos 4 pacientes (33,3%) presentaron lesiones: una esofagitis aguda grado 1-2A, 2 gastritis agudas no erosivas y una gastritis aguda hemorrágica. Se realizó endoscopia de control según los hallazgos endoscópicos previos. Solo 2 presentaron complicaciones posteriores. Conclusiones: Destacamos la valoración endoscópica en las primeras 24 h en todas las ingestas sintomáticas y deliberadas, así como la reevaluación estrecha en las ingestas ácidas, por asociar lesiones diferidas.

Artículo de reflexión Natalia Ponce de León fue atacada el 27 de Marzo de 2014 con un litro de ácido sulfúrico derramado por todo su rostro y parte importante de su cuerpo. La historia de esta mujer abrió paso al avance legislativo representado en el nacimiento de la Ley 1773 de 2016, que toma como delito autónomo los ataques con sustancias químicas o corrosivas y ácidos y que a su vez endureció las penas para atacantes y busca la protección integral de las víctimas. Desde la iniciativa legislativa hasta la promulgación de la Ley esta nueva normatividad representa avances positivos, sin embargo su contenido debe ser fortalecido en ciertos aspectos y debe armonizar con otras disposiciones normativas dirigidas a la protección y guarda de los derechos y reparación integral de los agredidos. La protección de sus derechos es el principal objetivo de la Ley 1773 de 2016, por esto es relevante conocer dichas disposiciones legales, cambios, beneficios y efectividad. Pregrado Abogado 42 p. Resumen. Abstract. Introducción. 1. De la Ley sin rostro y los vacíos jurídicos en la aplicación de sanciones penales en el caso Natalia Ponce de León. 2. Del tránsito legislativo que permitió la Ley 1773 de 2016. 2.1. 3. De la Ley 1773 y su relación con la violencia contra la mujer y feminicidio en Colombia. 4. Conclusiones. 5. Referencias

[ES] La tesis a desarrollar consiste en la aplicación de la metodología ARAMIS, que consiste en el uso del procedimiento MIRAS y, a continuación, del procedimiento MIMAH, para la evaluación del equipo potencialmente peligroso de una planta de producción de ácido levulínico a partir de biomasa compuesta principalmente de celulosa. La metodología se mejora a través de la integración de una herramienta informática para la evaluación de consecuencias (DNV Phast) para la determinación de las posibles consecuencias y peligros generados por los eventos finales identificados anteriormente, así como sus distancias de daño. Por otro lado, habrá una comparación de los resultados de este estudio con los de un análisis realizado anteriormente sobre otro proceso para la misma producción, cuyos datos se proporcionan, con el fin de evaluar cuál debería ser la alternativa más segura para la producción de ácido levulínico., [EN] The thesis to develop consists of the application of the ARAMIS methodology, consisting of the use of the MIRAS procedure and, after it, of the MIMAH procedure, for the evaluation of the potentially hazardous equipment of a levulinic acid production plant from biomass, mainly composed by cellulose. The methodology is enhanced through the integration of a computer tool for consequence assessment (DNV Phast) for the determination of potential consequences and hazards generated by the final events identified above, as well as their distances of damage. On the other hand, there will be a comparison of the results of this study with a previously performed analysis on another process for the same production, whose data are provided, in order to evaluate which should be the safer alternative is for the production of levulinic acid.

En base a la información científica revisado respecto al medicamento hierro polimaltosado + ácido fólico tabletas en combinación a dosis fija, a la fecha, no existe evidencia científica que demuestre que el uso de hierro polimaltosado + ácido fólico tabletas en combinación a dosis fija es más eficaz y seguro que el tratamiento con sulfato ferroso + ácido fólico en combinación a dosis fija (incluido en el PNUME) para el tratamiento de la anemia en pacientes gestantes, por lo que no se autoriza su uso hasta obtenerse mayor información científica.

En base a la revisión de la información respecto al medicamento Ácido valproico 500mg tableta, el Equipo Técnico acuerda modificar en el Petitorio Nacional Único de Medicamentos Esenciales (PNUME) la forma farmacéutica a Ácido valproico (valproato sódico) 500mg tableta de liberación modificada.