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Rheological and thermal Behavior of High-Density Polyethylene (HDPE) at Different temperatures

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Materials Sciences and Applications 2014年第13期5卷 923-931页

作者： Cynthia D’avila Carvalho Erbetta Getúlio f. Manoel Ana Paula Lelis Rodrigues Oliveira Maria Elisa Scarpelli Ribeiro e Silva Roberto fernando Souza freitas Ricardo Geraldo Sousa Polymer Science and technology Laboratory Chemical Engineering Department Engineering School Federal University of Minas Gerais Belo Horizonte Brazil

in the present work, rheological properties of HDPE samples were measured at temperatures of 150°C, 190°C and 230°C. it was shown, by oscillatory tests, at low frequencies, that, for temperatures of 150°C and 190°C, there was a predominance of the viscous behavior over the elastic one. At 230°C, there was a predominance of the elastic contribution, and there was an increase of the molar mass compared with the ones obtained from the tests at 150°C and 190°C. the results obtained from the temperature ramp oscillatory test showed that, up to around 248°C, the viscous behavior prevailed, the opposite being observed at higher temperatures. At 230°C the sample showed significantly lower values of strain when compared with the ones observed at 150°C and 190°C. Oxidative induction time (Oit), melting point and degree of crystallinity were determined by differential scanning calorimetry (DSC). the DSC results and the rheological measurements showed a completely different behavior for the HDPE samples at 230°C compared with the 150°C and the 190°C ones, suggesting that HDPE, at the temperature of 230°C, underwent thermo-oxidative degradation with the initial predominance of crosslinking.

关键词： HDPE Rheology Degradation DSC ftiR

About factorization of Quantum States with few Qubits

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Journal of Applied Mathematics and Physics 2017年第2期5卷 469-480页

作者： G. V. López G. Montes M. avila J. Rueda-Paz Departamen to de física Universidad de Guadalajara Guadalajara Mexico Centro Univeristario UAEM Valle de Chalco Valle de Chalco Estado de México México

through the study of the factorization conditions of a wave function made up of two, three and four qubits, we propose an analytical expression which can characterize entangled states in terms of the coefficients of t... 详细信息

关键词： Entangled State factorized State Decoherence Quantum Computing and information Chain of Spins System

Bromatological characteristics of sugarcane silages inoculated with Lactobacillus buchneri

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Bromatological characteristics of sugarcane silages inoculat...

the Effect of Gnaphafium oxyphyllum var. natalie on Cancer and Blood Cells

ⅩⅪ international Grassland Congress and the Ⅷ international Rangeland Congress

作者： J.C.Pinto C.L.S.avila H.C.P.figueiredo A.R.Morais O.G.Pereira R.f.Schwan Universidade federal de Lavras Minus Gerais Brazil Universidade federal de Vicosa Minas GeraisBrazil

＜正＞introduction the intense alcoholic fermentation by yeasts during sugarcane ensiling results into high rates of DM losses. inoculants containing the species *** have proved effective in inhibiting the growth of yeasts（Pedroso et al.,2005）. the objective of this work was to evaluate the effect of the addition of two strains of ***,one from a commercial inoculant and the other isolated from sugarcane silage,upon the fermentation profile of this forage plant.

关键词： crude protein dry matter fermentation profile fiber inoculants Saccharumspp

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Journal of Pharmacy and Pharmacology 2016年第5期4卷 231-239页

作者： Elisa Vega-avila Shindu irais Gomez-Covarrubias Adolfo Espejo-Sema Elizabeth Hernandez-Perez Maria de los Angeles Aguilar-Santamaria Departamento de Ciencias de la Salud. Universidad Autonoma Metropolitana. Unidad iztapalapa. Mexico D.F. 09340 Mexico Departamento de Biologia. Universidad Autonoma Metropolitana. Unidad iztapalapa. Mexico D.F. 09340 Mexico

Characterization of Chemical Bath Deposited CdS, CdSe and PbS

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材料科学与工程（中英文A版） 2011年第5X期1卷 692-704页

作者： Oscar Portillo Moreno Gustavo Abarca avila Jorge R. Cerna Juan Hernandez tecorralco Melissa Chavez Portillo Javier Martinez Juarez Rosendo Lozada Morales Orlando Zelaya Angel facultad de Ciencias Quimicas Benemerita Universidad Autonoma de Puebla Mexico Col. Sn. Manuel Puebla Pue. Mexico CiDS-iCUAP Benemerita Universidad Autonoma de Puebla Mexico. Col. Sn. Manuel Puebla Pue. Mexico fac. Ciencias fisicomatematicas Postgrado en Optoelectronica Benemerita Universidad Autonoma de Puebla Mexico Col. Sn Manuel Puebla Pue. Mexico Departamento de fisica Centro de investigacion y de Estudios de Estudios Avanzados del iPN 07360 Mexico D. F. Mexico

CdS, CdSe and PbS films were grown onto glass by chemical bath deposition (CBD). Different constant deposition temperatures (td) were employed in the range 0-80 °C with subintervals of 10 °C. Concentration of reagents, pH, and stirring were maintained constants. A microcrystalline mixture CdCO3 and CdS were grown. At intermediates td values a mixture of both materials present. i. e., for td? 40 °C, the intensity of the main of X-ray Diffraction (XRD) CdS peak is abruptly reduced. By scanning electronic microscopy (SEM) with td = 80 °C, concentration atomic: Cd = 49.10, S = 51.90, for td? 70 °C, increase of carbon and oxygen. the CdSe, average grain size (GS) increased monotonic with td, reaching saturation of 70 °C, with GS values of 5-16 nm. At low td values (0-20 °C), the structural phase was found, and the high td = 70 °C on material 5-16 nm was appreciated transition to phase: Wurzite (W)? Zinbclende (ZB) and phases mixture: W/ZB, grain size (GS) 9-27 nm. By (XRD), PbS grow in W phase at all films, for td = 60 °C, was observed preferential orientation in plane [111] with (GS) of 19-26 nm also a Gibbs free energy calculation is included.

关键词： CdSe 化学浴沉积 PBS 平均晶粒尺寸扫描电子显微镜表征吉布斯自由能薄膜生长

Characterization of Chemical Bath Deposited CdSe thin films Doped with S^2-

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材料科学与工程（中英文B版） 2011年第5期1卷 657-666页

作者： Jorge indalecio Contreras Rascon Oscar Portillo Moreno Gustavo Abarca avila Jorge R. Cerna Juan Hernandez tecorralco Javler Martinez Juare Rosendo Lozada Morales Orlando Zelaya Angel CiDS-iCUAP Benemerita Universidad Autonoma de Puebla 14 Sur y Av. Sn. Claudio Col. Sn. Manuel Puebla Pue. Mexieo facultad de Ciencias Quimicas Benemerita Universidad Autonoma de Puebla 14 Sur y Av. Sn. Claudio Col. Sn. Manuel Puebla Pue. Mexico facultad de Ciencias fisicomatematicas Postgrado en Optoelectroniea Benemerita Universidad Autonoma de Puebla 14 Sur y A v Sn. Claudio Col. Sn. Manuel Puebla Pue. Mexico Departamento de fisiea del Centro de investigacion y de Estudios Avanzados del iPN 07360 Mexico D. F. Mexico

CdSe thin films doped with S2-, growing on glass substrates using the chemical bath deposition (CBD) at temperature of t = 80 oC, with precursor solutions: CdCl2 0.01 M, KOH 0.1 M, 0.5 M, SeC(NH2)2 0.04 M, NH4NO3, SC(NH2)2 0.2 M, 5, 10, 15, 20, 25 and 30 mL of doping. the concentration of atoms was obtained by Scanning Electron Microscopy (SEM), S = 14.11-42.57, Cd = 49.11-59.59, and Se = 50.99-2.29, X-ray diffraction, identifies mixture of Wurzite/Zinc blende doped films phases and size of grain of 24-15 nm. Optical Absorption Spectra have redshifts of the forbidden band gap (Eg) of 1.8-2.3 eV. Raman spectra (RS) show the Raman shift, confirming formation of nanocrystals. from the dark conductivity vs. 1/kt behavior on the 100-500 K range, attributed to doping effects at the grain boundaries and quantum confinements. A thermodynamic model is proposed using the equation of Nernst to evaluate changes in the Gibbs free energy and investigate the spontaneity of reactions.

关键词：硒化镉薄膜化学浴沉积掺杂效应 CdSe 扫描电子显微镜 X射线衍射分析表征吉布斯自由能

女性心脏病患者产后心血管功能转归:一项全国范围研究

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中华高血压杂志 2019年第5期27卷 415-415页

作者：刘莉(译) 叶鹏(摘、审校) Lima f Nie Li Yang J Owens A Dianati-Maleki N avila C Stergiopoulos K 不详

在美国,关于女性心脏病患者产后主要不良心脑血管事件(major adverse cardiovascular and cerebrovascular events,MACCE)的数据有限,该研究旨在确定美国女性产后MACCE的患病率和预测因素。研究者对全国再入院数据库(2010-2014)中有和... 详细信息

在美国,关于女性心脏病患者产后主要不良心脑血管事件(major adverse cardiovascular and cerebrovascular events,MACCE)的数据有限,该研究旨在确定美国女性产后MACCE的患病率和预测因素。研究者对全国再入院数据库(2010-2014)中有和没有心脏病,分娩过的患者进行筛选。心脏病亚型包括心肌病、先天性心脏病(congenital heart disease,CHD)、心脏瓣膜病(valvular heart disease,VHD)和肺动脉高压(pulmonary hypertension,PH)。使用加权后的全国范围估算值确定42d 再人院的发生率和原因。使用多因素Logistic回归调整混杂因素,确定产后MACCE的独立预测因子。

关键词：心脏病患者心血管功能多因素Logistic回归产后女性 hypertension 转归心脑血管事件

Long-lasting effects of unplanned logging on the seed rain of mixed conifer-hardwood forests in southern South America

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Journal of forestry Research 2021年第4期32卷 1409-1418页

作者： Alexandre f.Souza Angela Luciana deÁvila Maristela M.Araújo Solon Jonas Longhi Departament of Ecology CBRio Grande Do Norte Federal UniversityCentral CampusLagoa NovaNatal 59072-970RNBrazil forest Growth Department Freiburg Im BreisgauBaden-Vurtemberga Forest Research InstituteWonnhaldestraße 4Freiburg im Breisgau 79104Germany forest Engineering Postgraduate Program Forestry DepartmentSanta Maria Federal UniversityRoraima Av.s/nCamobiSanta Maria 97105-900RSBrazil

Understanding the effects of disturbance on seed rain is critical to predict changes in forest species composition and *** effects on seed rain in a mixed conifer-hardwood forest complex in southern Brazil were *** year of seed rain data were collected from a large-scale observational experiment in logged and protected forests and quantity and average seed size weighted by species abundance(CWM)were compared between old-growth and logged stands 55 years after logging *** these data,variations in frequency of functional groups of species in the seed rain were examined to see if they could be attributed to *** show that the number of seeds per trap was highly right-skewed,ranging from 13 to 12,788 seeds per trap in one *** rain was affected by logging history,with seed traps in old-growth plots receiving significantly less seeds than traps in logged *** species included mean seed size weighted by species abundance were significantly smaller in logged than in old-growth *** difference persisted after the exclusion of Arawcaria a large-seeded pioneer which was intensively logged,although the difference of seed size between the two forest classes was greatly *** abundance in the seed rain differed significantly from the established tree community,between logged and oldgrowth *** composition of the seed rain was much more variable than the composition of the established tree community and its points more scattered over the ordination space than the points corresponding to the protected *** number of collected seeds across different functional groups of species significantly differed between logged and old-growth *** seed rain of logged forests reflects their arrested succes sion as indicated by reduced abundance of functional groups such as pioneers,large seeded pioneers and A raucaria,as well as reduced functional diversity.S eed rain differences between logged and old-

关键词： Arrested succession Brazil Logging Long-lived pioneers Seed rain

观察冠状动脉疾病病人心肌灌注:320-MDCt与82Rb PEt的比较

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国际医学放射学杂志 2018年第4期 500-500页

作者： R.N.Jr Dantas A.N.Jr Assuncao i.A.Marques M.G.fahel C.H.Nomura L.f.R.avila 吴迪 Computed tomography Department Heart InstituteIn-CorUniversity of Sao Paulo Medical School

目的尽管Ct多期相MPi在无创性心肌灌注成像（MPi）评估方面取得了进展,但其方案尚未与高度精确的82Rb PEt MPi进行比较。故本研究旨在评估82Rb PEt和320层Ct（320-Ct）MPi在疑似CAD病人中使用多期相方案的一致性。方法前瞻性纳入44例参... 详细信息

目的尽管Ct多期相MPi在无创性心肌灌注成像（MPi）评估方面取得了进展,但其方案尚未与高度精确的82Rb PEt MPi进行比较。故本研究旨在评估82Rb PEt和320层Ct（320-Ct）MPi在疑似CAD病人中使用多期相方案的一致性。方法前瞻性纳入44例参加MPi评估并接受双嘧达莫应激82Rb PEt和多期相320-Ct MPi（压力期间连续5次容积采集）的病人。统计分析使用R软件进行。结果总和压力评分≥4（κ=0.77,95%Ci:0.55～0.98,Pi:0.23～0.80,Pt MPi和82Rb PEt MPi对于评估中度危险性的可疑CAD病人,两者间存在一致性,多期相320-Ct MPi方案是可行的,可诊断并且具有相对较低的辐射照射量。

关键词： PEt MPi CAD Rb PEt