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Catalytic combustion of soot over ceria-zinc mixed oxides catalysts supported onto cordierite

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Journal of Environmental Sciences 2014年第3期26卷 694-701页

作者： Leandro Fontanetti Nascimento Renata Figueredo Martins Rodrigo Ferreira silva Osvaldo Antonio Serra Department of Chemistry FFCLRP University of Sao Paulo

Modified substrates as outer heterogeneous catalysts was employed to reduce the soot generated from incomplete combustion of diesel or diesel/biodiesel blends, a process that harms the environment and public health. The unique storage properties of ceria （CeO2） makes it one of the most efficient catalysts available to date. Here, we proposed that ceria-based catalysts can lower the temperature at which soot combustion occurs; more specifically, from 610℃ to values included in the diesel exhausts operation range （300-450℃）. The sol-gel method was used to synthesize mixed oxide-based catalysts （CeO2：ZnO）; the resulting catalysts were deposited onto cordierite substrates. In addition, the morphological and structural properties of the material were evaluated by XRD, BET, TPR-H2, and SEM. Thermogravimetric （TG/DTA） analysis revealed that the presence of the catalyst decreased the soot combustion temperature by 200℃ on average, indicating that the oxygen species arise at low temperatures in this situation, promoting highly reactive oxidation reactions. Comparative analysis of soot emission by diffuse reflectance spectroscopy （DRS） showed that catalyst-impregnated cordierite samples efficiently oxidized soot in a diesel/biodiesel stationary motor： soot emission decreased by more than 70%.

关键词： soot oxidation mixed oxides ceria

Al-Doping Effect on the Surface Morphology of ZnO Films Grown by Reactive RF Magnetron Sputtering

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Materials Sciences and Applications 2013年第12期4卷 761-767页

作者： Erica Pereira da silva Michel Chaves Gilvan Junior da silva Larissa Baldo de Arruda paulo Noronha Lisboa-Filho Steven Frederick Durrant José Roberto Ribeiro Bortoleto Technological Plasmas Laboratory Sao Paulo State University-UNESPSorocabaBrazil Group of Advanced Materials Sao Paulo State University-UNESPBauruBrazil

Zinc oxide (ZnO) and aluminum-doped zinc oxide (ZnO:Al) thin films were deposited onto glass and silicon substrates by RF magnetron sputtering using a zinc-aluminum target. Both films were deposited at a growth rate of 12.5 nm/min to a thickness of around 750 nm. In the visible region, the films exhibit optical transmittances which are greater than 80%. The optical energy gap of ZnO films increased from 3.28 eV to 3.36 eV upon doping with Al. This increase is related to the increase in carrier density from 5.9 × 1018 cm-3 to 2.6 × 1019 cm-3. The RMS surface roughness of ZnO films grown on glass increased from 14 to 28 nm even with only 0.9% at Al content. XRD analysis revealed that the ZnO films are polycrystalline with preferential growth parallel to the (002) plane, which corresponds to the wurtzite structure of ZnO.

关键词： ZnO Thin Films Surface Morphology RF Magnetron Sputtering

Recovery of rare-earth metals from aqueous solutions by bio/adsorption using non-conventional materials:a review with recent studies and promising approaches in column applications

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Journal of Rare Earths 2020年第4期38卷 339-355页

作者： Talles Barcelos da Costa Meuris Gurgel Carlos da silva Melissa Gurgel Adeodato Vieira University of Campinas School of Chemical EngineeringAlbert Einstein Avenue50013083e852 CampinasBrazil

The recovery of rare-earth metals(REMs)is of great economic and environmental interest,because of their high market prices and various industrial ***,with the increasing demand for high-purity rare-earth compounds,the separation and purification of these elements have gained considerable *** bio/adsorption process has been considered an alternative to recover these elements,by its simplicity,low cost and efficiency for recovery of REMs at low *** review article presents the recent progress regarding REM bio/adsorption published literature in batch system by different non-conventional bio/adsorbents,as well as a critical analysis of the technological challenges to be faced and future *** this purpose,the best application model(isotherm,kinetics),thermodynamic quantities and selection of eluents for desorption studies are also ***,in this review,the application of different bio/adsorbent materials were reviewed extensively in terms of the removal and recovery of REMs in continuous fixed-bed adsorption and regeneration ***,future aspects in bio/adsorption research and prospects for commercial applications were discussed.

关键词： Rare-earth metals Bio/adsorbents Adsorption kinetics Isotherm Batch desorption Continuous fixed-bed adsorption

Guarding tomato fruit setting in adverse temperatures through the miRNA166-S/HBt5A regulatory module

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Molecular Plant 2021年第7期14卷 1046-1048页

作者： Eder M.da silva Fabio T.S.Nogueira Centro de Energia Nuclear na Agricultura Universidade de Sao Paulo/USPPiracicabaSP 13400-970Brazil Laborat6rio de Genetica Molecular do Desenvolvimento Vegetal Departamento de Ciencias BiologicasESALQ/USPPiracicabaSP 13418-900Brazil

Fruits are defined as mature ovaries originated from a coordinated development between ovules(precursors of seeds)and carpels(precursors of the fruit body).Disconnecting the ovule development from carpel development is a long-desired goal in agriculture to generate seedless fruits easier to ***,pollination and fertilization are required to promote hormone pathways-i.e.,auxin and gibberellin-that are crucial for seed and fruit set(Gillaspy et al.,1993;Raghavan,2003).Even though developing seeds are central for normal fruit development,examples of seedless or parthenocarpic fruits are present in wild and cultivated species(Joldersma and Liu,2017).

关键词： Guard connecting originated

Potential role of Limosilactobacillus fermentum as a probiotic with anti-diabetic properties: A review

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World Journal of Diabetes 2022年第9期13卷 717-728页

作者： Diego Cabral Lacerda paulo César Trindade da Costa Paula Brielle Pontes Lucas Alves Carneiro dos Santos JoséPatrocínio Ribeiro Cruz Neto Cristiane Cosmo silva Luis Vanessa Polyana de Sousa Brito JoséLuiz de Brito Alves Department of Nutrition Health Sciences CenterFederal University of ParaíbaJoão Pessoa58051-900ParaíbaBrazil Department of Neuropsychiatry Health Sciences CenterFederal University of PernambucoRecife50670-901PernambucoBrazil Department of Nutrition Federal University of ParaíbaJoão Pessoa58045-190ParaíbaBrazil

Oxidative stress,inflammation,and gut microbiota impairments have been implicated in the development and maintenance of diabetes *** capable of recovering the community of commensal gut microbiota and controlling diabetes mellitus have increased in recent *** lactobacilli strains have an antioxidant and anti-inflammatory system capable of protecting against oxidative stress,inflammation,and diabetes *** studies and some clinical trials have demonstrated that Limosilactobacillus fermentum strains can beneficially modulate the host antioxidant and anti-inflammatory system,resulting in the amelioration of glucose homeostasis in diabetic *** review presents and discusses the currently available studies on the identification of Limosilactobacillus fermentum strains with anti-diabetic properties,their sources,range of dosage,and the intervention time in experiments with animals and clinical *** review strives to serve as a relevant and well-cataloged reference of Limosilactobacillus fermentum strains capable of inducing anti-diabetic effects and promoting health benefits.

关键词： Diabetes Mellitus Gut dysbiosis Oxidative stress Probiotics Limosilactobacillus fermentum

Morphological and Optical Characterizations of CaAl2O4 Doped with Trivalent Praseodymium

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Journal of Chemistry and Chemical Engineering 2015年第8期9卷 514-516页

作者： Valeria Rejane silva Brito Raquel Jovita dos Santos paulo Neilson Marques dos Anjos Severino Alves Junior Laboratory for Research and Innovation of Advanced Materials State University of Santa Cruz llheus Bahi 45662900 Brazil Department of Fundamental Chemistry Federal University of Pernambuco Recife Pernambuco 50670901 Brazil

This work was synthesized CaAl2O4 （calcium aluminate） doped with trivalent praseodymium ions. CaAl2O4 with praseodymium 1.0% and 0.5% were synthesized. The powders of aluminates were characterized by scanning electron microscopy and luminescence ***2O4, praseodymium ions, luminescence doped with praseodymium ion that showed less porosity in its grain structure and luminescent transitions that are dependent on the wavelengths of excitation and showing both types of transitions both 5d-4f and 4f-4f.

关键词： CaAl2O4 praseodymium ions luminescence

Elemental Composition of PM<sub>2.5</sub>in Araraquara City (Southeast Brazil) during Seasons with and without Sugar Cane Burning

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Journal of Environmental Protection 2015年第5期6卷 426-434页

作者： Flavio Soares silva Ricardo Henrique Moreton Godoi Romà T auler paulo Afonso de André paulo Hilário Nascimento Saldiva Rene van Grieken Mary Rosa Rodrigues de Marchi Physic and Chemistry Institute Federal University of Itajubá (UNIFEI) Itajubá Brazil Environmental Engineering Department Federal University of Paraná (UFPR) Curitiba Brazil Institute for Environmental Assessment and Water Research (IDAEA-CSIC) Barcelona Spain Department of Pathology Faculty of Medicine University of Sao Paulo (USP) Sao Paulo Brazil Department of Chemistry University of Antwerp Antwerp Belgium Analytical Chemistry Department Institute of Chemistry Univ Estadual Paulista (Unesp) Araraquara Brazil

Particulate matter with an aerodynamic diameter below 2.5 μm (PM2.5), present in polluted air, has been associated with a large spectrum of health impairments, mainly because of its deep deposition into the lungs. Araraquara City (Southeast Brazil) is surrounded by sugar-cane plantations, which are burned to facilitate the harvesting;this process causes environmental pollution due to the large amounts of soot that are released into the atmosphere. In this work, the elemental composition of PM2.5 was studied in two scenarios, namely in sugar-cane harvesting (HV) and in non-harvesting (NHV) seasons. The sampling strategy included one campaign in each season. PM2.5 was collected using a dichotomous sampler (10 L·min-1, 24 h) with PTFE filters. Information concerning the bulk elemental concentration was provided by energy-dispersive X-ray fluorescence. Enrichment factor analysis indicated that S, Cl, K, Cr, Ni, Cu, Zn, As, Cd and Pb were highly enriched relative to their crustal ratios (to Al). Principal component analysis was used to get some insight about the sources of the elements. Principal component 1 (PC1) explained 30.5% of data variance. The elements that had high loading (>0.7) were: S, Cr, As, and Pb;these are associated with combustion of fossil fuels. In principal component 2 (PC2), Cl, Cu, Zn, and Cd showed high loadings;these elements are associated with biomass burning. The Ni concentration found is three times larger than the threshold of risk for lung cancer, as recommended by the World Health Organization.

关键词： Sugar-Cane Burning PM2.5 Individual Particle Analysis EDXRF Cluster Analysis Principal Components Analysis

Mean and Interannual Variability of Maize and Soybean in Brazil under Global Warming Conditions

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American Journal of Climate Change 2013年第4期2卷 237-253页

作者： Flávio Justino Evandro Chaves Oliveira Rafael de Avila Rodrigues paulo Henrique Lopes Goncalves paulo Jorge Oliveira Ponte Souza Frode Stordal José Marengo Thieres G.da silva Rafael Coll Delgado Douglas da silva Lindemann Luiz Claudio Costa Departamento de Engenharia Agrícola Universidade Federal de ViçosaVicosaBrazil Universidade Federal Rural da Amazônia Instituto Sócio-Ambiental e dos Recursos HídricosBelémBrazil Department of Geosciences University of OsloOsloNorway Instituto Nacional de Pesquisas Espaciais Cachoeira PaulistaBrazil Universidade Federal Rural de Pernambuco Unidade Academica de Serra TalhadaSerra TalhadaBrazil Universidade Federal Rural do Rio de Janeiro Instituto de Florestas/Departamento de Ciencias AmbientaisSeropédicaBrazil

Brazil is responsible for 27% of the world production of soybeans and 7% of maize. Mato Grosso and Para states in Brazil are among the largest producer. The viability to the cultivation of maize (Zea mays) and soybeans (Glycine max), for future climate scenarios (2070-2100, GHG) is evaluated based on crop modeling (DSSAT) forced by observational data and regional climate simulations (HadRM3). The results demonstrated that a substantial reduction in the yield in particular for maize may be expected for the end of the 21st century. Distinct results are found for soybeans. By applying the A2 climate changes scenario, soybean yield rises by up top 60% assuming optimum soil treatment and no water stress. However, by analyzing the inter-annual variability of crop yields for both maize and soybean, could be demonstrated larger year-to-year fluctuations under greenhouse warming conditions as compared to current conditions, leading to very low productivity by the end of the 21st century. Therefore, these Brazilian states do not appear to be economically suitable for a future cultivation of maize and soybeans. Improved adaptation measures and soil management may however partially alleviate the negative climate change effect.

关键词： Climate Changes Soybeans Maize

Adenoma incidence decreases u nder the efect of polypectomy

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World Journal of Gastroenterology 2012年第11期18卷 1243-1248页

作者： Isadora Rosa paulo Fidalgo Jose Soares Susana Vinga Carla Oliveira Joao P silva Susana M Ferro Paula Chaves Antonio G Oliveira Carlos N Leitao Gastroenterology Department Instituto Portu-gues de Oncologia de Lisboa Francisco Gentil EPE 1099-023Lisboa Portugal Faculdade de Ciencias da Safldeda Universidade da Beira Interior 6200-506 Covilha Portugal Jose Soares Gastroenterology Department Hospital de SantoAntonio EPE 4099-001 Porto Portugal Instituto de Engenharia de Sistemas e Com-putadores: Investigacao e Desenvolvimento 1000-029 LisboaPortugal Hospital de Santo Antonio EPE 4099-001Porto Portugal Pathology Department Instituto Portugues deOncologia de Lisboa Francisco Gentil EPE 1099-023 LisboaPortugal Biostatistics Department Faculdade deCiencias M6dicas 1169-056 Lisboa Portugal

MM： To investigate whether, under the influence of pol ypectomy, the incidence of adenoma decreases with age.METHODS： Consecutive patients with colonic adenomas identified at index colonoscopy were retrospectively selected if they had undergone three or more complete colonoscopies, at least 24 mo apart. Patients who had any first-degree relative with colorectal cancer were excluded. Data regarding number of adenomas at each colonoscopy, their location, size and histological classification were recorded. The monthly incidence density of adenomas after the index examination was estimated for the study population, by using the person-years method. Baseline adenomas were excluded from incidence calculations but their characteristics were correlated with recurrence at follow-up, using the X^42 test.RESULTS： One hundred and fifty-six patients were included （109 male, mean age at index colonoscopy 56.8 ± 10.3 years）, with follow-up that ranged from 48 to 232 mo. No significant correlations were observed between the number, the presence of villous component, or the size of adenomas at index colonoscopy and the presence of adenomas at subsequent colonoscopies （P = 0.49, 0.12 and 0.78, respectively）. The incidence of colonic adenomas was observed to decay from 1.4% person-months at the beginning of the study to values close to 0%, at 12 years after index colonoscopy.CONCLUSION： Our results suggest the sporadic formation of adenomas occurs within a discrete period and that, when these adenomas are removed, all neoplasia-prone clones may be extinguished.

关键词： Colorectal cancer Colorectal adenoma In-cidence Age Polypectomy