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Stable NiO-CeO_(2) nanoparticles with improved carbon resistance for methane dry reforming

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Journal of Rare Earths 2022年第1期40卷 57-62页

作者： Andrea Cárdenas-Arenas Esther bailón-García Dolores Lozano-Castelló Patrick da costa Agustín bueno-López Department of Inorganic Chemistry University of AlicanteCarretera de San Vicente s/nE03080AlicanteSpain Sorbonne Universite Institut Jean Le Rond d'AlembertCNRS UMR 71902 place de la gare de ceinture78210Saint Cyr L'EcoleFrance

High surface area mixed oxide 8.7%NiO-CeO_(2) nanoparticles(122 m2/g;6-7 nm)were prepared using a reversed microemulsion method,and were tested for dry methane reforming(DRM).The catalytic activity of these nanoparticles remains stable under the severe conditions of DRM(700℃),and they show better carbon resistance than conventional NiO-CeO_(2) catalysts prepared without control of the *** activity and selectivity of nanoparticles and reference catalyst are similar,but nanoparticles reduce the accumulation of carbon by 63%during the DRM tests,which is a key feature for this *** and H_(2)-TPR suggest that the improved carbon resistance of the nanoparticles is due to the better interaction and cooperation between NiO and CeO_(2) mixed *** nanoparticles,the participation of cerium cations in the redox processes taking place during DRM stabilizes cationic species of *** the contrary,the catalyst prepared without control of the size suffers segregation of Ni during DRM reaction,and segregated Ni explains the higher catalytic formation of carbon.

关键词： Methane dry reforming Nickel Ceria Nanoparticle Rare earths

In-Vitro Micropropagation and Acclimatization of an Endangered Native Orchid Using Organic Supplements

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American Journal of Plant Sciences 2022年第3期13卷 380-393页

作者： Douglas De Stefano bárbara Nogueira Souza costa Jason Downing Esmaeil Fallahi Amir Ali Khoddamzadeh Department of Earth and Environment Institute of Environment Florida International University Miami FL USA Fairchild Tropical botanic Garden Coral Gables FL USA Parma Research and Extension Center Department of Plant Sciences University of Idaho Parma ID USA

In-vitro propagation is a technique that provides a vital solution for the conservation of endangered orchid species. The media used in tissue culture can be modified through the addition of inexpensive organic materials as an alternative to expensive synthetic additives. Some organic sources, such as coconut water and fruit juice, contain significant amounts of vitamins, amino acids, and organic compounds which can act as growth regulators, making these organic sources excellent additives for in-vitro cultivation. The aim of this study was to develop a protocol for in-vitro micropropagation and acclimatization of Epidendrum nocturnum using organic supplements in the growth media and various substrates at the acclimatization stage. banana powder, coconut water, and potato dextrose were added to a basal seed sowing media and evaluated for seed germination percentage and plantlet growth. In addition, various substrates such as coconut coir, horticultural charcoal, sphagnum moss, and wood bark were evaluated for height, number of leaves, and number of shoots in the acclimatization portion of this study. The culture medium with coconut water showed a greater germination percentage (71.00% and 76.75%) compared with the control (37.50% and 45.50%) at 60 and 90 days after seed sowing, respectively. Media with organic supplements showed greater values of plant length and number of roots compared with the control. The combination of coconut coir and horticultural charcoal was shown to be more efficient than the combination of sphagnum moss, horticultural charcoal, and wood bark, as results showed greater values of plant height and number of leaves at 30, 90, and 120 days after transplantation in acclimatization of E. nocturnum.

关键词： Tissue Culture Native Orchid Plant Growth Hormones Climate Change Epidendrum nocturnum

Hydrogeochemical Studies in Drought Scenarios: Canelones, Uruguay Case Study

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Journal of Geoscience and Environment Protection 2024年第5期12卷 188-217页

作者： Karina Pamoukaghlian Elena Alvareda Mariano Cáceres Rebeca Panzl Marcelo Aboy Sofìa da Rocha Pablo Gamazo María Paula Collazo Instituto de Ciencias Geoló gicas Facultad de Ciencias Universidad de la Rep&#250blica Montevideo Uruguay Departamento del Agua Centro Universitario Regional Litoral Norte Universidad de la Rep&#250blica Salto Uruguay Á rea Toxicolog&#237a Departamento Estrella Campos Facultad de Qu&#237mica Universidad de la Rep&#250blica Montevideo Uruguay

The water scarcity in quality and quantity is becoming more noticeable and an urgent concern around the world. In Uruguay, these issues become exacerbated by the need to obtain drinking water in coastal areas, influenced by the climate change. basic and structural geologies are strong conditioners in heterogeneous coastal aquifers. The objective of this study is to characterize the hydrochemistry of the fractured aquifers after having identified the main bearing fractures and the causes of aleatoreous water scarcity and quality problems, for hydric resources sustainable management. Identification of water bearing fracture, hydrogeochemical analysis and water quality evaluation are specific objectives. Some strategies were performed: 1) a base map in QGIS Software;2) fracture photointerpretation;3) geological correlation;4) statistical analysis of the background geochemistry data;5) ions analysis of strategically located wells. There were found water bearing fractures corresponding to 28 m3/h maximum flow rate for the NW-SE and 12 m3/h maximum flow rate for the NE-SW fracture direction, respectively. besides, there could be a problem related to the high Sodium (Na) and Chloride (Cl) levels. In this respect, having previous data from 25 well samples, ions geochemical analysis has been carried out for 14 wells from costa Azul and surrounding to have a first approach about the possible cause for the high values of Na (max. 385 mg/L) and Cl (max. 381 mg/L). The selected area for this study has a particular characteristic, because it corresponds to a heterogeneous fractured aquifer, which makes it difficult to catch water with enough flow rates and water quality to meet the population demand.

关键词： Water bearing Fractures Hydrogeochemistry Water Quality Sustainable Management

Antiglycation and antioxidant activities of the crude extract and saponin fraction of Tribulus terrestris before and after microcapsule release

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Journal of Integrative Medicine 2022年第2期20卷 153-162页

作者： Célia Cristina Malaguti Figueiredo Amanda da costa Gomes Filipe Oliveira Granero Joao Luiz bronzel Junior Luciana Pereira Silva Valdecir Farias Ximenes Regildo Márcio Goncalves da Silva Institute of Chemistry São Paulo State UniversityAraraquaraSão Paulo 14800-060Brazil Educational Foundation of the City of Assis AssisSão Paulo 19807-130Brazil Department of Chemistry School of SciencesSão Paulo State UniversityBauruSão Paulo 17033-360Brazil Department of biotechnology School of SciencesHumanities and LanguagesSão Paulo State UniversityAssisSão Paulo 19806-900Brazil

Objective:The present study investigated antiglycation and antioxidant activities of crude dry extract and saponin fraction of Tribulus *** also developed a method of microencapsulation and evaluated antiglycation and antioxidant activities of crude dry extract and saponin fraction before and after microcapsule ***:Antiglycation activity was determined by relative electrophoretic mobility(REM),free amino groups and inhibition of advanced glycation end-product(AGE)*** activity was determined by 2,2-diphenyl-1-picrylhydrazyl(DPPH),ferric ion-reducing antioxidant power(FRAP),nitric oxide(NO)and thiobarbituric acid reactive species(TbARS)*** were prepared using maltodextrin as wall material and freeze-drying as encapsulation *** characterization of microcapsules was evaluated by scanning electron microscopy,and encapsulation efficiency and microcapsule release were determined by total saponins *** and antioxidant assays were performed using crude dry extract and saponin fraction of *** before and after ***:Saponin fraction showed an increase of 32.8%total ***-performance liquid chromatography-mass spectrometry analysis showed the presence of saponins in the obtained *** evaluation by REM demonstrated that samples before and after release presented antiglycation activity similar to bovine serum albumin treated with ***,samples inhibited AGE formation,highlighting treatment with saponin fraction after release(89.89%).Antioxidant tests demonstrated antioxidant activity of the *** dry extract before encapsulation presented the highest activities in DPPH(92.00%)and TbARS(32.49%)*** fraction before encapsulation in FRAP test(499μmol Trolox equivalent per gram of dry sample)and NO test(15.13μmol nitrite formed per gram of extract)presented the highest ***:This study presen

关键词： Glycation Microencapsulation Oxidative stress Saponins Tribulus terrestris

Toxicity assessment of polyethylene microplastics in combination with a mix of emerging pollutants on Physalaemus cuvieri tadpoles

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Journal of Environmental Sciences 2023年第5期127卷 465-482页

作者： Amanda Pereira da costa Araújo Thiarlen Marinho da Luz Mohamed Ahmed Ibrahim Ahmed Mir Mohammad Ali Md.Mostafizur Rahman bojan Nataraj daniela de Melo e Silva damiàbarceló Guilherme Malafaia Post-Graduation Program in Environmental Sciences Federal University of GoiásGoianiaGO 74690-970Brazil Laboratory of Toxicology Applied to the Environment Goiano Federal InstituteUrutaíGO 75790-000Brazil Plant Protection Department Faculty of AgricultureAssiut UniversityAssiut 71526Egypt Department of Aquaculture Faculty of FisheriesAquaculture&Marine ScienceSher-e-Bangla Agricultural UniversityDhaka 1207Bangladesh Department of Environmental Sciences Jahangirnagar UniversitySavar 1342Bangladesh Unit of Toxicology Department of ZoologySchool of Life SciencesBharathiar UniversityCoimbatore 641046India Laboratory of Environmental Mutagenesis Federal University of GoiásGoianiaGO 74690-970Brazil Catalan Institute for Water Research(ICRA-CERCA) H_(2)O BuildingScientific and Technological Park of the University of GironaEmili Grahit 101Girona 17003Spain Water and Soil Quality Research Group Department of Environmental ChemistryInstitute of Environmental Assessment and Water Research(IDAEA-CSIC)JordiGirona 1826Barcelona 08034Spain Post-Graduation Program in Conservation of Cerrado Natural Resources Goiano Federal InstituteUrutaíGO 75790-000Brazil Post-Graduation Program in Ecology Conservationand BiodiversityFederal University of UberlandiaUberlandiaMG 38400-902Brazil Post-Graduation Programa in biotechnology and biodiversity Federal University of GoiásGoianiaGO 74605-050Brazil

Studies in recent years have shown that aquatic pollution by microplastics(MPs)can be considered to pose additional stress to amphibian ***,our knowledge of how MPs affect amphibians is very rudimentary,and even more limited is our understanding of their effects in combination with other emerging ***,we aimed to evaluate the possible toxicity of polyethylene MPs(PE-MPs)(alone or in combination with a mix of pollutants)on the health of Physalaemus cuvieri *** 30 days of exposure,multiple biomarkers were measured,including morphological,biometric,and developmental indices,behavioral parameters,mutagenicity,cytotoxicity,antioxidant and cholinesterase responses,as well as the uptake and accumulation of PE-MPs in *** on the results,there was no significant change in any of the parameters measured in tadpoles exposed to treatments,but induced stress was observed in tadpoles exposed to PE-MPs combined with themixture of pollutants,reflecting significant changes in physiological and biochemical *** principal component analysis(PCA)and integrated biomarker response(IbR)assessment,effects induced by pollutants in each test group were distinguished,confirming that the exposure of *** tadpoles to the PE-MPs in combination with a mix of emerging pollutants induces an enhanced stress response,although the uptake and accumulation of PE-MPs in these animalswas ***,our study provides newinsight into the danger to amphibians of MPs coexisting with other pollutants in aquatic environments.

关键词： Amphibians Environmental toxicology Micropollutants Emerging pollutants Aquatic pollution biomarkers

EFFECTIVE NETWORKS FOR REAL-TIME DISTRIbUTED PROCESSING

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Journal of Systems Science & Complexity 2011年第1期24卷 39-50页

作者： Gonzalo TRAVIESO Luciando da Fontoura costa Instituto de Fisica de Sao Carlos Universidade de Sao Paulo Av. do Trabalhador SSo-Carlensc 400 13566 - 590 Sao Carlos SP Brazil.

这份报纸把复杂网络的概念和方法用于模型的开发和由在许可的交货介绍上面的界限的分布式的即时系统与计算结果包预定的主人奴隶的模拟。二个代表性的互联模型被考虑：一致地。

关键词：分布式实时系统复杂网络分布式处理计算结果应用程序数据包随机和随机大

Movement behaviors and their association with depressive symptoms in brazilian adolescents:A cross-sectional study

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Journal of Sport and Health Science 2022年第2期11卷 252-259页

作者： bruno Goncalves Galdino da costa Jean-Philippe Chaput Marcus Vinicius Veber Lopes Luis Eduardo Argenta Malheiros Kelly Samara Silva Research Centre in Physical Activity and Health Federal University of Santa CatarinaFlorianopolis88040-900Brazil Healthy Active Living and Obesity Research Group Children’s Hospital of Eastern Ontario Research InstituteOttawaON K1H 8L1Canada

background:Physical activity,sleep,and sedentary behaviors compose 24-h movement behaviors and have been independently associated with depressive ***,it is not clear whether it is the movement behavior itself or other contextual factors that are related to depressive *** objective of the present study was to examine the associations between self-reported and accelerometer-measured movement behaviors and depressive symptoms in ***:Cross-sectional data from 610 adolescents(14-18 years old)were *** answered questions from the Center for Epidemiological Studies Depression scale and reported time spent watching videos,playing videogames,using social media,time spent in various physical activities,and daytime ***-worn accelerometers were used to measure sleep duration,sleep efficiency,sedentary time,and physical ***-effects logistic regressions were ***:Almost half of the adolescents(48%)were classified as being at high risk for depression(score≥20).No significant associations were found between depressive symptoms and accelerometer-measured movement behaviors,self-reported non-sport physical activity,watching videos,and playing ***,higher levels of self-reported total physical activity(odd ratio(OR)=0.92,95%confidence interval(95%CI):0.86-0.98)and volume of sports(OR=0.88,95%CI:0.79-0.97),in minutes,were associated with a lower risk of depression,while using social media for either 2.0-3.9 h/day(OR=1.77,95%CI:1.58-2.70)or>3.9 h/day(OR=1.67,95%CI:1.10-2.54),as well as higher levels of daytime sleepiness(OR=1.17,95%CI:1.12-1.22),were associated with a higher risk of ***:What adolescents do when they are active or sedentary may be more important than the time spent in the movement behaviors because it relates to depressive *** daytime sleepiness,promoting sports,and limiting social media use may benefit adolescents.

关键词： Accelerometry Depression Physical activity Sedentary behavior Sleep

Mechanical design of an ultra-light vertex detector prototype for CEPC

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Radiation Detection Technology and Methods 2022年第2期6卷 159-169页

作者： Jinyu Fu Zhijun Liang Hao Zeng Gang Li Mingyi Dong Huamin Qu Joao Guimaraes da costa Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China State Key Laboratory of Particle Detection and Electronics.Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China University of Chinese Academy of Sciences Beijing 100049China

background The Circular Electron Positron Collider(CEPC)is a large international scientific facility proposed to study the Higgs boson in great *** requires state-of-the-art detectors,including extremely precise vertexing and tracking devices,such as a silicon vertex *** Silicon vertex detector with the precision required by the CEPC has never been built before and needs extensive research and *** paper describes the mechanical design of a vertex detector prototype being built to explore the required technologies and the major *** The exceptional high spatial resolution of the CEPC vertex detector is achievable only with a detector of extremely low mass to limit particle *** paper proposes a mechanical design for the vertex detector prototype,highlighting the choice of low-mass materials,the analysis of support structures,the solution of detector cooling issues,and the drafts of procedures for detector *** The ultra-light support of the ladder(a structural unit of the CEPC vertex detector prototype),which is mainly made of carbon fiber reinforced polymer composite,has been *** fabrication process has also been *** supporting and cooling method of the vertex detector prototype has been designed and chosen with results from finite element analysis and computational fluid dynamics *** assembly and installation schemes for the prototype have been developed,and the respective tooling has also been *** performance of the vertex detector prototype,using this low-mass mechanical structure,was demonstrated with fast simulation to closely meet the CEPC physics requirement.

关键词： CEPC Silicon detector Mechanical design Carbon fiber reinforced polymer

Mechanical properties of a clay soil reinforced with rice husk under drained and undrained conditions

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Journal of Rock Mechanics and Geotechnical Engineering 2023年第10期15卷 2676-2686页

作者： Claudia Regina bernardi baldin Maiky Yamato Kawanami Weiner Gustavo Silva costa Vitor Reinaldo bordignon Cristhyano Cavali da Luz Ronaldo Luis dos Santos Izzo Federal University of Technology-Paraná CuritibaBrazil

Fiber-reinforced soils have been increasingly used in geotechnical *** the years,research has sought to understand and investigate the influences of fibers as reinforcement in soilefiber *** study assessed the behavior of clayey soil in the city of Curitiba(Paraná,brazil),adding rice husk fiber(RHF),an industrial waste from Cooperativa Agroindustrial in Alegrete(Rio Grande do Sul,brazil).To evaluate the effect of the presence of natural RHF on the mechanical behavior of compacted soil,aspects such as the influence of fiber content and the drained and undrained behaviors of the soil were evaluated through unconfined triaxial compression *** following tests were realized:soil granulometry,specific mass of solids and Atterberg *** were produced in quadruplicate for the soil and mixtures using the RHF contents of 0.5%,0.75%,1%and 1.5%to determine the unconfined compressive strength(UCS).Triaxial tests were realized on a pure soil specimen and the specimens with 1%RHF under confining pressures of 50 kPa,100 kPa,200 kPa and 400 *** interactions at the interface between husk surface and soil were analyzed using scanning electron microscopy(SEM).In UCS tests,specimens with RHF percentages of 1%and 1.5%presented the highest results,with an increment of 36%compared to the soil without *** results of the consolidated drained triaxial compression tests show that in terms of effective stress,there was a small difference in the strength of the compacted pure soil and soil with the addition of *** the undrained tests,the strength increased with the inclusion of husk,with a reduction of 50%in cohesion and an increment of 22%in friction angle for specimens containing RHF compared to the soil without RHF additions.

关键词： Clay soil Rice husk Soil reinforcemen