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Menopause is characterised by several hormonal changes through which women undergo aging. These changes lead to psychological, somatic, urogenital and vasomotor symptoms that influence the quality of life of women. Studies have shown that physical exercise can benefit women in the pre- and postmenopausal stages. However, the physiological benefits of exercise during the menopausal period have been less explored, as well as which type of exercise is most recommended at this stage of life. Therefore, the present review aimed to investigate the physiological changes promoted by the practice of physical exercise during the menopause period. A search for scientific articles was performed in the PubMed database using the descriptors ‘menopause’ and ‘exercise’ and the ‘AND’ connector. The period selected for this study was from 2014 to 2018. After applying the inclusion and exclusion criteria, five articles were selected. As a result, studies suggest that physical exercise promotes hormones, body composition and positive cardiovascular changes, decreases menopausal symptoms and improves psychosocial health. In addition, it is associated with an improvement in the quality of life.

During the satellite’s operations, simulation tools perform an important role in ensuring the space mission success. In this sense, the models implemented in the context of an operational satellite simulator that enables analysis of health status and maintenance during operations shall reflect the current satellite behavior with high fidelity. Moreover, it is complicated to obtain all analytical models of a satellite’s disciplines, considering its aging. This paper proposes an Artificial Neural Network (ANN) to reproduce the battery voltage behavior of a large sun-synchronous remote sensing satellite, the CBERS-4, currently in operation. Using the genetic algorithm to find the best network architecture of ANN, the neural model for this application presented an error of less than 1%, demonstrating its feasibility to obtain a high fidelity model for an operational simulator enabling extend analyses. The paper addresses advanced techniques aligned with the space industry’s future, increasing the ability to analyze a large amount of data and improve the space system’s operation.

Real (RBW) and synthetic brewery wastewater (SBW) were treated by aqueous phase reforming (APR) with different 3%Pt/C catalysts for H2 production from the biomass-derived organic load. APR enabled simultaneous treatment of the wastewater and valorisation to H2 and alkanes of the biomass-derived organic load. In the catalytic APR of SBW, TOC and COD removal was higher than 60% after reaction time of the experiments. The addition of KOH or NaOH to SBW resulted in a slightly lower TOC and COD removal, however higher yields to H2 and percentage of valuable gases were obtained in those cases where KOH was added. Catalyst with basic support and low contribution of micropores showed the best performance in the APR of SBW + KOH (∼50% of H2 and 8.9 mmol H2/g COD). The concentration of anions detected in the liquid effluents varied with the catalysts tested and with the concentration of base, suggesting different reaction pathways. Increasing the concentration of KOH led to CO2-free H2 without significant changes in H2 yield. The results obtained with RBW were in good agreement with those from SBW, although the significantly different behaviour of some catalysts suggests the need of tuning their properties according to the composition of the wastewater.

Graphene oxide (GO) membranes on Nylon support were modified by UV-assisted reduction to control their behavior in the filtration of water containing organic pollutants. Pyridine, phenol, 2-naphthol and disperse blue 3 were used as probe pollutants to determinate the molecular weight cut-off (MWCO) of the membranes prepared. The membranes were prepared with GO loads of 0.04 and 0.06 mg cm−2 and subjected to UV radiation from a Hg lamp (30 W m−2) for 30–60 min. The non-irradiated membranes showed MWCO ca. 300 Da, with rejection values above 90 % for disperse blue 3, while rejection for 2-naphtol reached 64 %. Irradiation resulted in substantial removal of oxygen surface groups, leading to staking of GO sheets and a decrease of interlayer space. These structural changes narrowed the size of pores thus reducing solutes passage. Rejection of 2-naphtol reached 83 %, i.e. decreasing MWCO to ca. 150 Da. The increase in the rejection of solutes was higher for membranes with a GO load of 0.06 mg cm−2, however similar water permeability was achieved regardless the GO load. UV-reduction shows a high potential for controlling the rejection of solutes by GO membranes on Nylon support while maintaining good permeability, The authors greatly appreciate financial support from Spanish AEI through the projects RTI2018-098431-B-I00 and PID2021-122248OBI00, and the Comunidad de Madrid for Manuel Fernandez-M ´ arquez ´ (PEJ-2018-AI/IND-11505; PEJ-2018PR-AI/IND-20881) and Raul Pla (PEJ-2020-AI/IND-18302) financial support

Mn-based solid oxygen carriers supported on MgAl2O4 were prepared by the microwave-assisted combustion method followed by wet impregnation of the active phase. The oxygen carriers were characterized by X-ray diffraction, temperature-programmed reduction and scanning electron microscopy with energy-dispersive spectroscopy of the surface. The study aimed to evaluate the influence of the thermal treatment on the structure and reactivity of the oxygen carriers. Reactivity tests using coal as fuel were carried out in a thermobalance at temperatures of 750–850 °C to evaluate the behavior of the carriers. The results revealed that oxygen carriers, which were subjected to only a heat treatment after the impregnation step (MnC1), showed more reactive surfaces presenting a greater number of non-reactive and irreversible phase and thus displaying lower oxygen transport capacity as well as poorer reactivity. The carriers prepared by heat treating the support after the combustion reaction and again after the impregnation step (MnC2), showed higher oxygen transport capacity and greater reactivity with coal at 850 °C. The better reactivity is associated with the formation of Mg6MnO8 and Mn2O3 phases.

Significant research efforts have been devoted to characterizing smallholding productive systems and assessing the relative contribution of small-scale farming to global food production. However, there is a noted paucity of studies addressing the determinants of and contributors to income generation of smallholders around the world, particularly in the Amazon forest. Moreover, while road development in the Amazon has been heavily discussed, the impacts of infrastructure projects, such as road paving, on smallholders’ livelihoods remain uncertain. Here we explore the relevance of agriculture, livestock rearing and collection of non-timber forest products (NTFP) as income providers of smallholders in the Amazon forest in Madre de Dios-Peru, after the paving of Interoceanic South Highway (ISH), a large infrastructural project connecting Acre state in Brazil with Cusco in Peru. We interviewed 62 smallholder families in an area of 403 km2 along the road from Inapari to Mazuko near the tri-national border of Brazil, Peru and Bolivia. We applied a multinomial statistical model to estimate the proportion of annual net revenue related to each productive system from selected predictor variables. Our results show that smallholders’ net revenue originates from a mix of productive systems including agriculture (rice, corn), livestock rearing (cows) and others (poultry, pigs, sheep) as well as NTFP extractivist activities (Brazil nut). Average net revenue is of USD 35.2 ± 25.7 ha−1yr−1 suggesting that economic returns to smallholders remain low even after the paving of ISH. This indicates that connection with markets alone is not sufficient to increase rents of smallholder families.

Objective Skin health and beauty are a cornerstone of general well-being in humans. Anti-ageing cosmetics are used to provide a healthy and youthful appearance. Among the different cosmetic actives, antioxidants are incorporated in anti-ageing products due to their beneficial effects in preventing and minimizing the signs of skin ageing. This work aims to understand how anti-ageing formulations changed in the past 7 years regarding pure antioxidants composition. Methods Data were collected from anti-ageing formulations commercialized in main stores and pharmacies in the Portuguese market. The study started on 2011 and was updated with products launched or whose composition has been renewed on 2013, 2015 or 2018. Results Ascorbic acid and tocopherol and their derivatives were consistently the most used antioxidants in anti-ageing formulations; followed by niacinamide and retinyl palmitate. Seven ascorbic acid derivatives are currently used in anti-ageing formulations while only three tocopherol derivatives were identified in this study. Several combinations of antioxidants were routinely found, mainly tocopherol (or tocopherol derivatives) with other antioxidants and tocopherol with tocopherol derivatives. We have not identified emerging antioxidants with great impact in anti-ageing formulations even though niacinamide and retinyl palmitate exhibited over 10% more usage in 2018. Conclusion This insight is relevant to the cosmetic industry providing a better understanding of the scientific-based formulation of modern cosmetics and supports the need for innovative antioxidants in anti-ageing cosmetics.

This paper reports for the first time on the aqueous phase reforming (APR) of a brewery wastewater, which was synthetically prepared according to a real effluent composition. Home-made Pt (3 wt. %) catalysts supported on different carbon materials, have been tested for this purpose at temperatures of 473 and 498 K. The effects of the supports and the organic load of the wastewater on the results of APR have been evaluated. Well characterized commercial carbons with different pH slurry and porous texture have been used as catalyst supports. A wide range of wastewater organic load has been tested, varying the COD from about 1500 to more than 11,200 mg/L, which corresponded to TOC values around 500 and more than 4000 mg/L, respectively. The highest removal of TOC and COD was observed for catalyst supported on highly mesoporous carbon blacks with virtually no microporosity and high pH slurry. At the lowest wastewater organic load (1531 mg/L CODinitial), TOC and COD removal up 99% was achieved and 93% of the TOC was converted into gases, with H2 and alkanes representing more than 70% of the total gas volume generated. The removal of organic matter in the liquid phase decreased at increasing its concentration in the starting wastewater, although the resulting gas contained a higher percentage of H2. Increasing the temperature allowed a higher TOC and COD removal, gas production, carbon conversion to gas and H2 yield. Some deactivation of the catalysts was observed after five successive uses, which can be attributed to partial blockage of the active Pt sites by carbonaceous deposits. The results obtained allow considering APR as an environmentally promising solution for these biomass-derived wastewaters providing also an interesting way of valorisation to H2-rich gas.

Aqueous phase reforming (APR) coupled to catalytic wet air oxidation (CWAO) has been investigated as an approach to remove phenolic compounds from wastewater, converting them into valuable gases. Partial oxidation of phenol was achieved in the first CWAO stage trying to minimize mineralization so to allow a high yield to valuable gases in the second APR stage. APR runs were carried out with different mixtures of compounds corresponding to phenol oxidation pathway (phenol, quinones, long and short chain acids) and representing different degrees of oxidation in CWAO stage. A range of TOC and COD removal (74–90%) was observed in APR stage for the single compounds, with higher removal for long chain acids. Likewise, long chain acids provided with the highest conversion to gases. APR of mixtures rich in acids gave the highest yield to CH4 (11.0 mmol CH4/g TOCinitial). H2 production was low in all cases, due to competing direct conversion of long and short chain acids into CH4. TOC and COD removal from wastewater was similar in APR-CWAO and APR, however the conversion to gases and the yield to CH4 were markedly higher for APR-CWAO, thus overcoming the difficulties previously observed in the direct APR of phenol.

A systematic and comparative study was made to determine the influence of perovskite-type LaAlO3 and commercial α-Al2O3 on the performance of nickel-based catalysts in dry reforming of methane (DRM). The perovskite-type LaAlO3 was selected due to its characteristics of solid state semiconductor with oxygen vacancies and high structural stability. The catalysts were characterized by X-ray diffraction (XRD), X-ray fluorescence spectroscopy (XRF), N2 adsorption-desorption, temperature programmed reduction (TPR-H2), thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The catalyst performance was evaluated based on activity tests (600–800 °C) and short- and long-term stability (10 and 20 h) at 700 °C at a GHSV (Gas Hourly Space Velocity) of 18 and 72 L g−1 h−1. The TPR-H2 profiles indicate that the oxygen vacancies on the perovskite surface exerted a strong effect on the reduction temperature and reducibility of the NiO nanoparticles, resulting in weak Ni0/support interaction. The results of the tests after 10 h under GHSV of 18 L g−1 h−1 indicate that the Ni/LaAlO3 catalyst is 7.8 and 11.5% more stable than Ni/α-Al2O3 in the conversions of CH4 and CO2, respectively. The higher stability and activity of Ni/LaAlO3 is directly ascribed to the presence of NiO (3.38 wt%) after activation, which promoted the formation of carbon nanotubes (CNT) and increased the dispersion of the metallic phase. Even under severe conditions of activation and reaction (high GHSV), as in the long-term test, the Ni/LaAlO3 catalyst showed a 37.2% higher H2 yield than the Ni/α-Al2O3. Analyses by TEM indicate that the Ni/α-Al2O3 catalyst exhibited deactivation problems associated with sintering effects. Thus, the presence of structural defects and surfaces rich in oxygen vacancies makes LaAlO3 perovskite a potential support for application in methane catalytic reforming processes.

The effect of H2 availability in the catalytic reduction of NO3− was studied through experimental tests and theoretical estimations of mass transfer regime for H2, CO2 and NO3−. The experiments were carried out in a fixed bed reactor packed with bimetallic 0.75% (w) Pd-Cu catalysts supported on granular activated carbon at 25 °C. External mass transfer limitations were only significant in the case of H2 and resulted in lower selectivity to NH4+, particularly in the low gas surface velocity range (0.09–0.019 cm/s). Low availability of H2, becoming the limiting reagent for the reaction, contributed to lower selectivity to NH4+ due to lower H:N ratio at the catalyst surface. Decreasing space–time also led to lower selectivity to NH4+, probably due to the neutralization of OH− by the available H+ at catalytic sites, thus controlling local pH and favoring N2 production. Reduction of selectivity to NH4+ was achieved with lower loss of activity and NO3− conversion when gas flow was decreased than when liquid flow was decreased. The results indicate that the design and operation of reactors for the catalytic reduction of NO3− should consider conditions leading to H2 transfer control in order to reduce selectivity to NH4+, even though this could be at the expense of reaction rate and NO3− conversion.

This paper reports on the catalytic performance and deactivation in aqueous phase reforming of wastewater streams for H2 production. Brewery wastewater was chosen as representative of this type of effluent. The effect of catalyst support textural characteristics was evaluated using an activated carbon and different modified supports obtained by infiltration and carbonization of a phenolic resol resin into activated carbon. The effect of active phase was evaluated using Pt and PtRe catalysts with different metal molar ratio. At short time on stream values, Pt catalysts supported on modified activated carbon showed higher H2 production than those supported on unmodified activated carbon, indicating that a lower microporosity facilitates the transport of reactants to catalytic active sites and release of reaction products. Bimetallic PtRe catalysts showed higher activity than Pt, particularly using a metal molar ratio of 1:1, which yielded the highest H2 production (117.2 μmol min−1). Despite the different catalysts tested, early and significant deactivation was observed. The characterization of used catalysts allows postulating the adsorption of organic species and/or coke-like matter deposition on the catalysts surface as main causes of deactivation.

Cerium aluminate is a perovskite type that presents AmBnO3 that has interesting physical, morphological properties and crystalline structures; however it has not been deeply studied when synthesized by microwave-assisted self-combustion specifically. Thus, the objective of this work was to synthesize CeAlO3 by microwave-assisted combustion method in an one-step using only one fuel (urea, 250% excess). Formulations were identified by CexAl2-xO3 (x = 0, 0.25, 0.50, 0.75 and 1; in mol), an α-Al2O3–standard was used how reference. X-ray diffraction (XRD), scanning electron microscopy (SEM-EDS and SEM-FEG), specific gravity, absorption spectroscopy in the ultraviolet and visible region (diffuse reflection), Fourier transform infrared spectroscopy (FTIR) and Raman were the techniques used in the characterizations. The results show that CeAlO3 was formed in the synthesis, as well as CeAl11O18 and CeO2 phase. In the diffuse reflection of light, the beginning of the increase in reflectivity occurs at wavelengths close to 380 nm and band-gap between 3.36 to 3.47 eV; the presence of microstructural and macrostructural defects impacted on the variation of reflectivity in the UV–visible region and on the variation of densities (5.06–5.96 g.cm−³); heterogeneous morphologies expressed by diversified surfaces, particulates tending to equiaxial symmetry and perforation signals, in addition to prismatic crystals growing parallel to the surface. The FTIR confirms the formations of α-Al2O3 and Raman confirms the presence of residual carbon. These results are relevant, since the work produced perovskites with stable structures in a single step, optimizing the manufacturing process of these materials with the elimination of calcination after synthesis.

In this work, zinc aluminate spinel was prepared by two methods of directly synthesis (without calcination): microwave assisted combustion and hydrothermal method. The materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and N2-adsorption/desorption isotherms. The XRD patterns confirmed the formation of cubic ZnAl2O4 spinel structure with no secondary phases for both synthesis routes, whereas the hydrothermal method yielded powders with crystallite size 3 times smaller (6.9 nm), as compared to the powders produced by microwave assisted combustion method (25.6 nm). The micrographs revealed agglomerated powders with plate-like morphologies for both routes. Nitrogen adsorption/desorption isotherms (BET) revealed higher surface area (183 m2.g-1) and greater pore volume (0.173 cm3.g-1) for ZnAl2O4 powders prepared by the hydrothermal method.

A diatomita brasileira foi usada como suporte catalítico para a reforma a seco do metano. As fases ativas utilizadas foram Ni e Co em diferentes concentrações. Os catalisadores foram calcinados a 500 °C por 5 he caracterizados por DRX, BET, TPR e SEM. Os resultados de DRX dos catalisadores mostraram que houve formação de espinélio de NiCo2O4 para os catalisadores bimetálicos, além das fases esperadas de NiO e Co3O4. Os testes catalíticos foram realizados a 700 °C com velocidade espacial de18 L⋅h-1⋅g-1, demonstrando um efeito sinérgico entre as fases ativas (Ni e Co). O catalisador Ni8Co2/ D apresentou maior rendimento para H2, melhor estabilidade e menor taxa de formação de carbono entre os catalisadores bimetálicos. Os resultados de MEV após a reação indicaram a presença de filamentos de carbono. De acordo com os resultados, a diatomita brasileira pode ser aplicada como suporte catalítico na reação de reforma a seco do metano. La diatomita brasileña se utilizó como soporte catalítico para el reformado en seco de metano. Las fases activas utilizadas fueron Ni y Co a diferentes concentraciones. Los catalizadores se calcinaron a 500 °C durante 5 h y se caracterizaron por XRD, BET, TPR y SEM. Los resultados de XRD de los catalizadores mostraron que había formación de espinelas de NiCo2O4 para catalizadores bimetálicos, además del las fases esperadas de NiO y Co3O4. Las pruebas catalíticas se realizaron a 700 °C con una velocidad espacial del 18 L⋅h-1⋅g-1, lo que demuestra un efecto sinérgico entre las fases activas (Ni y Co). El catalizador Ni8Co2/D mostró el mayor rendimiento para H2, la mejor estabilidad y la menor tasa de formación de carbono entre catalizadores bimetálicos. Los resultados de SEM después de la reacción indicaron la presencia de filamentos de carbono. Según los resultados, la diatomita brasileña se puede aplicar como soporte catalítico en la reacción de reformado en seco del metano. Brazilian diatomite was used as catalytic support for the dry reforming of methane. The active phases used were Ni and Co at different concentrations. The catalysts were calcined at 500 °C for 5 h and characterized by XRD, BET, TPR and SEM. The XRD results of the catalysts showed that there was formation of NiCo2O4 spinels for bimetallic catalysts, in addition to the expected NiO and Co3O4 phases. Catalytic tests were performed at 700 °C with a space velocity of 18 L⋅h-1⋅g-1, demonstrating a synergistic effect between the active phases (Ni and Co). The Ni8Co2/D catalyst showed the highest yield for H2, the best stability and the lowest rate of carbon formation between bimetallic catalysts. SEM results after the reaction indicated the presence of carbon filaments. According to the results, brazilian diatomite can be applied as a catalytic support in the dry reforming reaction of methane.

Ionic liquids (ILs) are good electrical conductors and organic liquid compounds at room temperature, with potential applicability in water electrolysis for H2 generation. The objective of this work is to describe the synthesis, characterization and study of the feasibility of ionic liquid 1-methyl-3-(2,6-(S)-dimethyloct-2-ene)-imidazolium tetrafluoroborate (MDI-BF4) as electrolyte to produce hydrogen through electrolysis of water. The synthesized MDI-BF4 was characterized by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC), mid-infrared spectroscopy with Fourier Transform by method of attenuated total reflectance (FTIR-ATR), nuclear magnetic resonance spectroscopy of hydrogen (NMR 1H) and cyclic voltammetry (CV). The yield of the synthesis were calculate by the TGA and DSC. From the results: The infrared spectroscopy identified the functional groups of the compound and the B-F bond at 1053 cm-1. The NMR 1H analyzed and compared with literature data confirms the structure of MDI-BF4. The yield of the synthesis of MDI-BF4 which was 88.84%. The current density achieved by MDI-BF4 in the voltammogram shows that the IL can conduct electrical current regardless the concentration of water, indicating that the MDI-BF4 is a potential electrolyte for hydrogen production from water electrolysis. Los líquidos iónicos (IL) son buenos conductores eléctricos y compuestos líquidos orgánicos a temperatura ambiente, con aplicabilidad potencial en la electrólisis del agua para la generación de H2. El propósito de este trabajo es describir la síntesis, caracterización y estudio de la viabilidad del líquido iónico 1-metil-3-(2,6-(S)-dimetiloct-2-eno)-imidazolio tetrafluoroborato (MDI-BF4) como electrolito para producir hidrógeno mediante de la electrólisis del agua. El MDI-BF4 sintetizado se caracterizó por análisis termogravimétrico (TGA) y calorimetría diferencial de barrido (DSC), espectroscopia de infrarrojo medio con transformada de Fourier por método de reflectancia total atenuada (FTIR-ATR), espectroscopia de resonancia magnética nuclear de hidrógeno (RMN 1H) y voltamperometría cíclica (CV). El rendimiento de la síntesis se calculados por TGA y DSC. De los resultados: La espectroscopía infrarroja identificó los grupos funcionales del compuesto y el enlace B-F a 1053 cm-1. La RMN 1H analizada y comparada con los datos de la literatura confirma la estructura de MDI-BF4. El rendimiento de la síntesis de MDI-BF4 que fue del 88,84%. La densidad de corriente alcanzada por MDI-BF4 en el voltamograma muestra que el IL puede conducir corriente eléctrica independientemente de la concentración de agua, lo que indica que MDI-BF4 es un electrolito potencial para la producción de hidrógeno a partir de la electrólisis del agua. Líquidos iônicos (LIs) são bons condutores elétricos e compostos orgânicos líquidos em temperatura ambiente, com potencial aplicabilidade em eletrólise de água para geração de H2. O objetivo desse trabalho é descrever a síntese, caracterização e estudo da viabilidade do líquido iônico 1-metil-3-(2,6-(S)-dimetiloct-2-eno)-imidazólio tetrafluoroborato (MDI-BF4) como eletrólito para produzir hidrogênio por meio eletrólise da água. O MDI-BF4 sintetizado foi caracterizado por análise termogravimétrica (TG) e calorimetria de exploratória diferencial (DSC), espectroscopia de infravermelho médio com transformada de Fourier pelo método de refletância total atenuada (FTIR-ATR), espectroscopia de ressonância magnética nuclear de hidrogênio (NMR 1H) e voltametria cíclica (CV). Os rendimentos da síntese foram calculados pelo TG e DSC. Dos resultados: A espectroscopia de infravermelho identificou os grupos funcionais do composto e da ligação B-F em 1053 cm-1. O NMR de 1H analisado e comparado com dados da literatura confirma a estrutura do MDI-BF4. O rendimento da síntese de MDI-BF4 foi de 88,84%. A densidade de corrente alcançada pelo MDI-BF4 no voltamograma mostra que o LI pode conduzir corrente elétrica independente da concentração de água, indicando que o MDI-BF4 é um eletrólito potencial para produção de hidrogênio a partir da eletrólise da água.

There is a noted lack of information on the effectiveness of investments in forest fire management in Brazil. Here, we quantify the budget expenditures of one private and one public fire-management program. We then compare burned areas within conservation units (CUs) and private rural properties (PPs) with and without investments in fire management in the Brazilian Amazon and Cerrado biomes. Investments in fire management in CUs total US$ 0.51 ha−1 yr−1 in the Amazon and US$ 5.32 ha−1 yr−1 in the Cerrado. Roughly, 94% of the public investment in fire management in CUs is only assigned to suppression activities, although seven CUs in Cerrado have undertaken innovative Integrated Fire Management (IFM) that includes prevention practices. Cerrado CUs with brigades for fire suppression have reduced burned area by 12%, on average, compared with CUs without brigades. Further, CUs that also included prevention practices as part of IFM reduced burned areas by an additional 6% from CUs with only fire suppression practices. Investments in both fire prevention and suppression on private lands amounted to US$ 15.89 ha−1 yr−1. We identify a reduction of 50%, on average, in burned areas after PPs joined the fire mitigation program of Alianca da Terra. In face of increasingly disruptive wildfires alongside finite financial resources, we call for the need of a mix of cost-effective private and public fire management programs with strong emphasis on prevention practices.

Alumina powders with high specific surface area (>200 m2g-1) were obtained quickly, easily and using only aluminum nitrate and urea (as fuel) through the microwave-assisted combustion method applying low power (450 W) and low fuel content. The powders obtained were calcined at temperatures of 550, 750 and 950 °C. The X-ray diffraction and Fourrier Transform Infrared (FTIR) results indicate that γ-Al2O3 was formed at temperatures of 550 and 750 °C, while the α and γ phases were identified in calcined alumina at 950 °C. The increase in calcination temperature strongly influenced the specific surface area and the pore size distribution, however no effect on the pore diameter was observed. The Al2O3 powder calcined at 550 °C was evaluated as catalytic support due to its most appropriate textural properties. The catalyst Ni/Al2O3 (Ni-A550) was prepared by wet impregnation method and calcined at 550 °C/3 h. The physical-chemistry properties were evaluated by X-ray diffraction, temperature programmed reduction and scan electron microscopy techniques. The results show that the Ni-A550 have high conversion of CH4 and CO2 and good H2 yield using a gas hourly space velocity (GHSV) of 72 L g−1 h−1. Therefore, the synthesized Al2O3 presents as a potential catalytic support material.

The present paper studied the influence of the concentrations of nickel and iron and the reaction temperature in catalysts tested in the dry reforming of methane, using a factorial design to optimize the H2 yield ( Y H 2 ) . Iron was selected due to its low cost compared with other noble metals and since it can be introduced into the MgAl2O4 spinel structure due to its various oxidation states. The results revealed that Fe was incorporated within the spinel structure, rather than simply forming oxide. The catalytic tests revealed that an increase in the temperature and in the concentration of iron improved significantly the catalytic performance as evidenced by the factorial analysis. The findings showed that increasing the temperature from 650 °C to 850 °C resulted in an increase of at least 20% in conversions of CH4 and CO2. Through the mathematical model it was possible to estimate a reduction of 61% in the amount of nickel without loss in Y H 2 .

Coupled hydrogenation and aqueous-phase reforming (APR) was studied as an approach to enhance H2 production from brewery wastewater, where maltose is the main component. Hydrogenation of maltose-bearing wastewater produced essentially maltitol. APR stage was performed over PtPd/C catalysts. Faster catalyst deactivation was observed in the APR of maltose than in the APR of maltitol, especially at high feedstock concentration. Higher H2 selectivity and yield were achieved in the APR of maltitol. The increase of temperature from 175 to 225 °C changed the reaction pathways, favouring the production of C1-C2 alkanes for both feedstocks. Higher selectivity to liquid-phase products was obtained in the APR of maltose, evidencing also reaction routes favouring the formation of solid carbonaceous deposits that lead to higher catalyst deactivation. The coupled process can be considered as efficient since H2 production compensated for H2 consumption in the hydrogenation stage and catalyst durability was increased.

This work is an exploratory study about the application of Aqueous Phase Reforming (APR) in the treatment of sanitary sewage, for reuse purposes. The removal of organic matter in terms of TOC, the elimination of micro pollutants (caffeine, carbamazepine, diclofenac and ibuprofen) and the production of hydrogen and alkanes were evaluated. Batch reactors were employed for the treatment of synthetic sewage using a Pt catalyst supported on a commercial carbon black. APR was found to be suitable to remove TOC and micro pollutants from sewage. Total removal was achieved for carbamazepine and diclofenac, whereas for caffeine and ibuprofen, the removal levels exceeded 90 %. Removal of TOC was also observed in tests where only the metal-free carbon support was used, most probably due to adsorption and hydrothermal carbonization, which could be considered as a route for organic matter removal, although low production of valuable gases was observed. In the catalysed experiment in addition to TOC, removal significant production of H2 and CH4 was achieved. The application of APR to wastewater makes possible to remove pollutants and micro pollutants and simultaneously valorize organic matter to valuable gases.

This work analyses the application of aqueous phase reforming as a treatment and valorisation method for fruit juice wastewater enabling production of H2 and alkanes from renewable source. The variables considered were pH, organic load and salinity of wastewater, since they are fluctuant and can affect the performance of biological treatments most commonly used. The experiments were carried out in batchwise, at 493 K and 24–28 bar for 4 h using a 3% Pt/C catalyst. Single compounds (glucose, fructose, citric acid, ascorbic acid, galacturonic acid) and fruit juice wastewater were tested as feedstocks. Organic carbon removal from wastewater was higher in the reforming of glucose and fructose within 7–10 pH range, while for organic acids and fruit juice wastewater a higher removal was obtained at pH 2. H2 yield and selectivity increased at increasing pH, due to better conditions for water-gas shift reaction and abstraction of CO2. H2 production by aqueous phase reforming of fruit juice wastewater was little affected by pH, yielding around 6.6 mmol H2/g initial chemical oxygen demand, in the pH range tested. Alkanes were also produced, with higher proportion of CH4 than other alkanes at high pH (10–12). A wide operation window was observed regarding organic load of fruit juice wastewater, although organic carbon removal declined slightly at the highest loads tested. Salinity did not affect organic carbon removal, while H2 yield decreased from 7.8 to 4.2 mmol H2/g initial chemical oxygen demand at high salinity, probably due to catalyst deactivation. Aqueous phase reforming is proved to be an alternative to biological treatment methods with low sensibility to fluctuations in the characteristics of wastewater.

This paper presents a new preparation method of a catalytic precursor LaNiO3 perovskite type in one-step using chitosan as a chelating agent. During synthesis La and Ni nitrates were added into a solution containing chitosan, placed into an oven to decompose the reagents and subsequently calcined. The perovskite was characterized by X-ray diffraction (XRD), scanning electron microscopy with chemical microanalysis (SEM-EDS), temperature-programmed reduction (TPR) and thermogravimetric analysis (TGA). The catalytic tests were conducted in a space velocity of 18 Lh−1g−1 at three temperatures: 600, 700 and 800°C. The characterization results indicated the formation above 95% of LaNiO3 phase with good chemical homogeneity at lower temperature with metallic area and dispersion compatible with literature. The catalytic test results showed good levels of CH4 and CO2 conversions and good yields of CO and H2. Therefore, the described method is a simple, fast and low-cost route to prepare LaNiO3 for hydrogen production via dry reforming of methane.

This study investigated the effect of a modified photoactivation protocol using two simultaneous light-curing units on the shear bond strength (SBS) of brackets to enamel. Metal brackets were bonded to bovine incisors using the resin-based orthodontic cement Transbond XT (3M Unitek). Four photoactivation protocols of the orthodontic cement were tested (n=15): Control: photoactivation for 10 s on each proximal face of the bracket at a time; Simultaneous: photoactivation for 10 s on both proximal faces of the bracket at the same time; One side-20s: photoactivation for 20 s at one proximal face of the bracket only; and One side-10s: photoactivation for 10 s only at one proximal face of the bracket. SBS was tested immediately or after 1000 thermal cycles. Adhesive remnant index (ARI) was classified. Data were subjected to two-way ANOVA and Student-Newman-Keuls' test (α=0.05). Pooled means ± standard deviations for SBS to enamel (MPa) were: 10.2±4.2 (Control), 9.7±4.5 (Simultaneous), 5.6±3.1 (One side-20s), and 4.6±1.9 (One side-10s). Pooled SBS data for immediate and thermal cycled groups were 6.3±2.6 and 8.8±5.2. A predominance of ARI scores 1-2 and 0-1 was observed for the immediate and thermally cycled groups, respectively. In conclusion, simultaneous photoactivation of the orthodontic cement using two light-curing units, one positioned at each proximal face of the bracket, yielded similar bonding ability compared to the conventional light-curing method. Photoactivation of the orthodontic cement at one proximal face of the bracket only is not recommended, irrespective of the light-curing time used.

Response surface methodology based on Box-Behnken design (BBD) was successfully applied for the optimization of the UV-LED/FeTiO3 activated persulfate (PS) process. Disperse Blue 3 (DB3) azo dye oxidation was carried out in a quartz jacketed stirred batch reactor using 405 nm UV at 10 W/m−2 as radiation source. The effects of temperature, catalyst concentration and persulfate dose upon the total organic carbon (TOC) removal were investigated. Optimum operating conditions were found to be: ilmenite: 320 mg/L−1, PS: 1.56 g/L−1 and 67°C. Under these conditions, 96% mineralization was achieved. Ecotoxicity of the final effluent was evaluated using Aliivibrio fischeri bacteria, finding a negligible toxicity., Comunidad Autónoma de Madrid and MINECO have supported this work through projects S2013/MAE-2716 and CTM2016-76454-R, respectively. Jefferson E. Silveira and Wendel S. Paz gratefully acknowledge the support from CAPES: Science Without Borders Program, Ministry of Education Brazil, under grants BEX-1046/13-6 and BEX-9476/13-0 respectively.

In the current work, an exploratory study on the application of catalytic aqueous phase reforming (APR) to the treatment of fish-canning wastewater was performed for the first time. Pt/C (3%, w) catalysts were supported on different commercial carbon supports (two activated carbons and a carbon black) and tested in the APR of tuna-cooking wastewater. The effect of the supports and the reaction systems (batch vs. semi-continuous) on the performance of the catalysts was tested. The stability of the catalysts upon 3 successive reuse cycles was checked. TOC and COD removal ranged within 45-60%, which was ascribed to adsorption on the supports, hydrothermal carbonization and APR. The percentage of valuable gases (H2 and alkanes) reached up to 18% of the gas production showing the potential of APR for the valorization and treatment of wastewater. The production of gases is affected by the high chloride, acetate and phosphate concentrations, which may provoke catalyst deactivation. The use of a catalyst with a basic support significantly increased the production of gases and the H2 percentage in the gas fraction. Gas production was higher in semi-continuous compared to batch operation, maybe because the withdrawn gas displaces the reaction towards the products. The percentage of alkanes in the gas phase decreased upon successive catalyst reuse cycles at the expense of H2, which is probably due to sintering of Pt nanoparticles with the corresponding decrease of the number of low-coordinated Pt sites promoting methanation reactions, The authors greatly appreciate financial support from Spanish MINECO (CTQ2015-65491-R). A. S. Oliveira thanks the Spanish MINECO for a research grant (BES-2016-077244)