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游戏的力量

作者： (美)Charles E. schaefer，(美)Donna Cangelosi

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生产聚丙烯短纤和薄膜带的挤压机生产线

国外纺织技术（化纤．染整．环境保护分册） 1994年第4期 20-25页

作者： Klaus schaefer 德国Barmag公司

一、简介聚丙烯在聚合物的家族中占有直越来越重要的地位,近十年来,由于聚合物和加工技术的不断发展使得聚丙烯与其它人造和天然纤维相比,处于有利的竞争地位,出于经济原因,以及聚丙烯的下列特性正在不断地开发出新的应用领域:易于加... 详细信息

一、简介聚丙烯在聚合物的家族中占有直越来越重要的地位,近十年来,由于聚合物和加工技术的不断发展使得聚丙烯与其它人造和天然纤维相比,处于有利的竞争地位,出于经济原因,以及聚丙烯的下列特性正在不断地开发出新的应用领域:易于加工、易于熔化染色、高绝缘性、不吸湿性、优良的吸油性以及其它许多特性。

关键词：聚丙烯短纤维薄膜带挤压机生产线

Identifying the temperature effect on the vibrations of functionally graded cylindrical shells w.th porosities

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Applied Mathematics and Mechanics(English Edition) 2018年第11期39卷 1587-1604页

作者： Yanqing w.NG Chao YE J.w.ZU Department of Mechanics Northeastern University Key laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern University schaefer School of Engineering and Science Stevens Institute of Technology

The free thermal vibration of functionally graded material(FGM) cylindrical shells containing porosities is investigated. Both even distribution and uneven distribution are taken into account. In addition, three thermal load types, i.e., uniform temperature rise(UTR), nonlinear temperature rise(NLTR), and linear temperature rise(LTR), are researched to explore their effects on the vibration characteristics of porous FGM cylindrical shells. A modified pow.r-law.formulation is used to describe the material properties of FGM shells in the thickness direction. Love’s shell theory is used to formulate the straindisplacement equations, and the Rayleigh-Ritz method is utilized to calculate the natural frequencies of the system. The results show.that the natural frequencies are affected by the porosity volume fraction, constituent volume fraction, and thermal load. Moreover,the natural frequencies obtained from the LTR have insignificant differences compared w.th those from the NLTR. Due to the calculation complexity of the NLTR, w. propose that it is reasonable to replace it by its linear counterpart for the analysis of thin porous FGM cylindrical shells. The present results are verified in comparison w.th the published ones in the literature.

关键词： functionally graded material(FGM) cylindrical shell porosity free vibration thermal load Rayleigh-Ritz method

Apolipoprotein B100 is required for hepatitis C infectivity and Mipomersen inhibits hepatitis C

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w.rld Journal of Gastroenterology 2016年第45期22卷 9954-9965页

作者： Esperance AK schaefer James Meixiong Christina Mark Amy Deik Daniel L Motola Dahlene Fusco Andrew.Yang Cynthia Brisac Shadi Salloum w.nyu Lin Clary B Clish Lee F Peng Raymond T Chung Gastrointestinal Unit Massachusetts General Hospital Bossston MA 02114 United States Department of Medicine Harvard Medical School Bossston MA 02114 United States both of the Broad Institute of Harvard and M.I.T. Cambridge MA 02115 United States Temple University Health System Cambridge MA 02142 United States

AIM To characterize the role of apolipoprotein B100(apoB 100) in hepatitis C viral(HCV) infection. METHODS In this study, w. utilize a gene editing tool, transcription activator-like effector nucleases(TALENs), to generate human hepatoma cells w.th a stable genetic deletion of APOB to assess of apoB in HCV. Using infectious cell culture-competent HCV, viral pseudoparticles, replicon models, and lipidomic analysis w. determined the contribution of apoB to each step of the viral lifecycle. w. further studied the effect of mipomersen, an FDAapproved antisense inhibitor of apoB 100, on HCV using in vitro cell-culture competent HCV and determined itsimpact on viral infectivity w.th the TCID50 method. RESULTS w. found that apo B100 is indispensable for HCV infection. Using the JFH-1 fully infectious cell-culture competent virus in Huh 7 hepatoma cells w.th TALENmediated gene deletion of apoB(APOB KO), w. found a significant reduction in HCV RNA and protein levels follow.ng infection. Pseudoparticle and replicon models demonstrated that apo B did not play a role in HCV entry or replication. How.ver, the virus produced by APOB KO cells had significantly diminished infectivity as measured by the TCID-50 method compared to w.ldtype virus. Lipidomic analysis demonstrated that these virions have a fundamentally altered lipidome, w.th complete depletion of cholesterol esters. w. further demonstrate that inhibition of apoB using mipomersen, an FDA-approved anti-sense oligonucleotide, results in a potent anti-HCV effect and significantly reduces the infectivity of the virus. CONCLUSION Apo B is required for the generation of fully infectious HCV virions, and inhibition of apo B w.th mipomersen blocks HCV. Targeting lipid metabolic pathw.ys to impair viral infectivity represents a novel host targeted strategy to inhibit HCV.

关键词： Apolipoprotein Lipid Hepatitis C virus Gene silencing Viral replication

Nonlinear free vibration of piezoelectric cylindrical nanoshells

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Applied Mathematics and Mechanics(English Edition) 2019年第5期40卷 601-620页

作者： Yanqing w.NG Yunfei LIU J.w.ZU Department of Mechanics Northeastern University Key laboratory of Ministry of Education on Safe Mining of Deep Metal Mines Northeastern University schaefer School of Engineering and Science Stevens Institute of Technology

The nonlinear vibration characteristics of the piezoelectric circular cylindrical nanoshells resting on an elastic foundation are analyzed. The small scale effect and thermo-electro-mechanical loading are taken into account. Based on the nonlocal elasticity theory and Donnell's nonlinear shell theory, the nonlinear governing equations and the corresponding boundary conditions are derived by employing Hamilton's principle. Then,the Galerkin method is used to transform the governing equations into a set of ordinary differential equations, and subsequently, the multiple-scale method is used to obtain an approximate analytical solution. Finally, an extensive parametric study is conducted to examine the effects of the nonlocal parameter, the external electric potential, the temperature rise, and the w.nkler-Pasternak foundation parameters on the nonlinear vibration characteristics of circular cylindrical piezoelectric nanoshells.

关键词： piezoelectric cylindrical nanoshell nonlinear vibration Donnell's nonlinear shell theory nonlocal elasticity theory multiple-scale method size effect

COVID-19疫情期间成都市地面臭氧污染特征及气象成因分析

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环境科学学报 2021年第10期41卷 4200-4211页

作者：祁宏张小玲康平 Klaus schaefer 向卫国邓中慈卢宁生雷雨成都信息工程大学大气科学学院高原大气与环境四川省重点实验室成都610225 成都平原城市气象与环境四川省野外科学观测研究站成都610225

受COVID-19疫情影响,我国各地采取了一系列封锁管控措施,由此导致大气污染物排放强度降低.本文以成都市为例,分析了2020年上半年的气象条件和大气污染浓度特征,并重点对臭氧浓度变化及同期对比结果进行了细致分析.结果表明:(1)与2019年... 详细信息

受COVID-19疫情影响,我国各地采取了一系列封锁管控措施,由此导致大气污染物排放强度降低.本文以成都市为例,分析了2020年上半年的气象条件和大气污染浓度特征,并重点对臭氧浓度变化及同期对比结果进行了细致分析.结果表明:(1)与2019年同期相比,除O_(3)外的5种污染物(NO_(2)、CO、SO_(2)、PM_(10)、PM_(2.5))浓度均降低,降幅分别为13.60%、8.96%、6.30%、4.56%、1.80%,而O_(3)浓度却异常升高,升幅最大值分别出现在2月(35.1%)和5月(36.1%).(2)2020年上半年,O_(3)浓度高值出现时间较2015—2019年提前,气象条件较有利于臭氧的生成.100 hPa和500 hPa位势高度为正距平,气温、日照时数较往年升高,相对湿度和降水量下降,以静小风为主.(3)2020年4月25日—5月6日臭氧污染持续时间长,主要是由于复工复产导致臭氧前体物排放增加,以及稳定的天气形势,使成都长时间处于高温(>30℃)、低湿(40%~60%)、静小风(1.3 m·s^(-1))等不利扩散的气象条件下.气团后向轨迹和污染潜在源区表明研究区受到来自成都偏东一带及川南地区高污染气团短距离输送的影响.

关键词：成都市新冠疫情气象条件后向轨迹潜在源分析

Soil and climate equally contribute to changes in the species compositions of Brazilian dry forests across 300 km

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Journal of Plant Ecology 2020年第2期13卷 171-176页

作者： Daniel M.Arruda Luiz F.S.Magnago Ricardo R.C.Solar Reinaldo Duque-Brasil Priscyla M.S.Rodrigues Rubens M.Santos Carlos E.G.R.schaefer Instituto de Geociências Universidade Federal de Minas GeraisBelo HorizonteMinas GeraisBrazil Centro de Formação em Ciências e Tecnologias Agroflorestais Universidade Federal do Sul da BahiaItabunaBahiaBrazil Instituto de Ciências Biológicas Universidade Federal de Minas GeraisBelo HorizonteMinas GeraisBrazil Instituto de Ciências da Vida Universidade Federal de Juiz de ForaGovernador ValadaresMinas GeraisBrazil Colegiado de Ecologia Universidade Federal do Vale do São FranciscoSenhor do BonfimBahiaBrazil Departamento de Ciências Florestais Universidade Federal de LavrasLavrasMinas GeraisBrazil Departamento de Solos Universidade Federal de ViçosaViçosaMinas GeraisBrazil

Aims Understanding the factors that control biodiversity distributions at different spatial scales has been a key challenge for conservation *** biodiversity,reflected in differences in species compositions among sites(beta diversity),can be derived from species replacement(turnover)and is driven by multiple ***,w. sought to tackle this issue through tw. questions related to threatened Brazilian seasonally dry forests:(i)w.at is the contribution of species turnover to beta diversity?and(ii)w.ich factors drive variations in species compositions among forest patches?Methods w. sampled tree species and environmental variables(soils and climate)in 17 dry forest patches spaced almost 300 km *** used the beta diversity partitioning framew.rk to determine the contribution of *** used redundancy analysis,w.th properly controlled spatial structure,to assess the contributions of the environmental and spatial factors to the variations of the species *** Findings Beta diversity among the patches w.s mainly represented by the turnover component(98.2%),w.th Simpson dissimilarity superior to other regions of the country(means of 0.89 and 0.71 in multiple site and pairw.se measures,respectively).The environmental factors measured explained more than space,representing 30.3%of the variation of the species composition,of w.ich 28.1%w.s nonspatially *** suggest that 300 km represents a threshold at w.ich edaphic and climatic predictors have similar effects in determining community turnover(14.9%and 12.6%,respectively,w.thout spatial structure).Thus,conservation strategies should be considered across landscapes to effectively protect tropical forest diversity,as even considering the different climatic aspects covered by the scale,landscaped edaphic varieties are important drivers of species turnover.

关键词： beta diversity environmental filter habitat fragmentation landscape structure phytogeography

Effect of Excipients on Recombinant Interleukin-2 Stability in Aqueous Buffers

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American Journal of Analytical Chemistry 2021年第10期12卷 347-372页

作者： A. S. Prakasha Gow.a Andrew.D. schaefer Terry K. Schuck Department of Raw.Materials Eurofins BioPharma Product Testing Lancaster USA

In order to retain structural and functional integrity, protein medicines are frequently stabilized w.th excipients in aqueous solutions. The goal of this investigation w.s to see how.stable IL-2 is w.th excipients that are acceptable for cell therapy. w. investigated the time-dependent stability of commercially available recombinant IL-2 in aqueous solutions (CTS, RPMI, PBS, and w.ter) at different temperatures [2°C - 8°C, room temperature (20°C ± 2°C) and 37°C] in the presence of excipients (EDTA, methionine, histidine, and glycine) over a period of up to 30 days. To detect and quantify IL-2, reversed phase high performance liquid chromatography w.s employed. Electrophoresis on a sodium dodecyl sulfate polyacrylamide gel w.s used to assess conformational stability. w. discovered that IL-2 stability w.s improved in aqueous solutions including excipients, and that it may have retained its biological activity and sterility in these conditions.

关键词： Interleukin-2 Excipients Stability RP-HPLC SDS-PAGE

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更高的速度

现代制造 2004年第29期 44-45页

作者： Reinhold schaefer

机床的发展趋势是使用免维护的线性电机。与传统的线性电机相比,这种电机具有更快的加速度和更高的效率。新一代的线性电机还可以提供更优良的定位精度。

关键词：线性电机电气传动分辨率直接传动技术