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1450篇 您的检索式:作者名="Wetzel"
    题名 作者 年代 出处 被引量
1纳米碳化硅填充环氧树脂复合材料的摩擦磨损特性显示文摘 以提高环氧树脂的摩擦磨损性能为目的,研究了纳米碳化硅粒子填充环氧树脂复合材料的滑动干摩擦磨损特性,着重探讨纳米粒子表面接枝改性、纳米粒子含量、摩擦条件等对复合材料摩擦学性能的影响。通过对复合材料磨损表面的形貌分析,以及复合材料的热变形性能和表面硬度的测定,探讨了复合材料的磨损机理。结果表明,纳米碳化硅粒子能在很低的含量下提高环氧树脂耐磨性、并降低其摩擦系数,而经过接枝处理后的纳米碳化硅粒子填充复合材料的上述性能改善更为明显,耐磨性比环氧树脂提高近4倍,摩擦系数降低36%。这说明在SiC纳米粒子表面引入聚丙烯酰胺接枝链后,由于界面的强相互作用(包括化学键合与链纠缠),有效地提高了复合材料的抵抗裂纹引发能力等性能,从而有利于改善其摩擦学性能。纪秋龙 章明秋 容敏智 WETZEL B FRIEDRICH K 2004复合材料学报2004,21,6:32
2德国公共剧院的效率:随机前沿分析法显示文摘近年来,文化服务机构等非营利性部门的经济表现一直是一个备受关注的问题。一方面是因为文化机构对公共资金的依赖度较高,另一方面是因为对公共预算的需求量越来越大。为了能够以最小成本来有效分配资源,负责对公共预算进行分配的政府部门就必须借助于可靠的表现指标。针对这一问题,本文对德国公共剧院1991/1992年和2005/2006年各季度的效率进行了分析。本研究采用了随机前沿分析法,检验了成本最小化行为在这一领域是否存在。此外,本文还采用了若干个面板数据模型来分析非观测到的异质性对效率估计的影响,不同模型对非观测到的异质性的解释力有所差别。研究结果表明,成本最小化行为在这一领域并不存在。因此,对于德国公共剧院来说,基于成本函数分析的效率分析法似乎并不适用。此外,研究还发现,不同剧院之间存在较大的非观测到的异质性,因而在各模型的效率分析中出现了显著差异。这说明,如果不将非观测到的异质性考虑在内,效率值就会有所偏颇。总之,此项研究发现,在公共文化领域要实现资源的合理应用,仍有很多工作要做。Anne-Kathrin Last Heike Wetzel 马绯璠 2010文化艺术研究2010,3,4:6
3新疆吐鲁番盆地中侏罗统张北足迹(Changpeipus,兽脚类)的重新研究(英文)显示文摘详细描述了中国西北部新疆吐鲁番市鄯善足迹点、中侏罗统三间房组的兽脚类足迹组合。连同新发现在内,共描述了143个足迹,并阐明其不同的保存状况与额外形态变化。在足迹分类学上,这批足迹被归入石炭张北足迹(Changpeipus carbonicus),该足迹种常见于中国其他侏罗纪足迹点。前人的研究认为此地有两种不同的足迹形态,但研究表明这是由软且湿滑的基底造成的额外形态变化。足迹的结构特征亦不支持此地存在不同的足迹种。此外,对比了其他化石点类似的足迹,认为张北足迹为单型属,即模式种石炭张北足迹。鄯善足迹点的足迹长度从12.2 cm(几个孤立的样本)到47 cm,足迹应由不同年龄段的、小型至中型的同类造迹者或不同类的造迹者所留。奇异的足迹状态包括了一个滑动造成的足迹,足迹由三道平行条带构成,条带应为第II,III和IV趾所留。一个与其关联的'正常'足迹可能与该滑动足迹构成一个单步。与足迹共生的、丰富的无脊椎动物遗迹化石支持该化石点的沉积环境是一个逐步扩大和深化的湖泊。前人的研究将此地的无脊椎动物遗迹化石归入洛克迹(Lockeia),新的研究将其归入福尔斯迹(Fuersichnus),这类遗迹被归于泥食性昆虫幼虫或其他无脊椎动物所留。福尔斯迹指示的环境特征是在泥泞的河漫滩或湖泊边缘居住与/或觅食。邢立达 Hendrik KLEIN Martin G. LOCKLEY Andreas WETZEL 李忠东 李建军 Gerard D. GIERLINSKI 张建平 松川正树 Julien D. DIVAY 周隆 2014古脊椎动物学报2014,52,2:6
4重塑能源-中国:能效在中国面向2050年路线图中的作用显示文摘作为《巴黎协定》承诺的一部分,中国计划在2030年左右达到二氧化碳(CO_2)排放峰值并争取尽早达峰。在研究如何实现上述减排承诺的前提下,中美研究人员组成的团队构建了一个自下而上的中国能源供需综合模型。基于该模型对比分析了两种情景的差异,即沿着当前趋势发展的参考路径情景以及'重塑能源'替代路径情景。'重塑能源'替代路径是指为满足国家需求,在2050年前最大程度地应用当前成本有效的能源效率策略和可再生能源。结果表明,如果中国走更积极的重塑能源路径,那么其二氧化碳排放量可比参考路径提前11年达峰。本文重点分析了在更积极的路径下能源效率策略对于二氧化碳减排的作用。除能源效率外,本研究还分析了燃料替换(从碳密集型燃料转向其他燃料)的减排作用。结果表明,对于重塑能源情景,能源效率提高及相关策略贡献了中国2050年二氧化碳总减排潜力的75%,而燃料替换仅占25%。为在中国实现上述具有显著成本效益的能效潜力。Lynn Price Nina Khanna Nan Zhou David Fridley Ali Hasanbeigi Hongyou Lu Feng Wei 戴彦德 田智宇 杨宏伟 白泉 朱跃中 熊华文 张建国 Jon Creyts Kate Chrisman Ellen Franconi Josh Agenbroad Michael Bendewald Yi Ke Robert McIntosh David Mullaney Clay Stranger Daniel Wetzel Cvrd Yee 2018科学与管理2018,38,3:3
5Optical force-induced nonlinearity and self-guiding of light in human red blood cell suspensions显示文摘Osmotic conditions play an important role in the cell properties of human red blood cells(RBCs),which are crucial for the pathological analysis of some blood diseases such as malaria.Over the past decades,numerous efforts have mainly focused on the study of the RBC biomechanical properties that arise from the unique deformability of erythrocytes.Here,we demonstrate nonlinear optical effects from human RBCs suspended in different osmotic solutions.Specifically,we observe self-trapping and scattering-resistant nonlinear propagation of a laser beam through RBC suspensions under all three osmotic conditions,where the strength of the optical nonlinearity increases with osmotic pressure on the cells.This tunable nonlinearity is attributed to optical forces,particularly the forward-scattering and gradient forces.Interestingly,in aged blood samples(with lysed cells),a notably different nonlinear behavior is observed due to the presence of free hemoglobin.We use a theoretical model with an optical force-mediated nonlocal nonlinearity to explain the experimental observations.Our work on light self-guiding through scattering biosoft-matter may introduce new photonic tools for noninvasive biomedical imaging and medical diagnosis.Rekha Gautam Yinxiao Xiang Josh Lamstein Yi Liang Anna Bezryadina Guo Liang Tobias Hansson Benjamin Wetzel Daryl Preece Adam White Matthew Silverman Susan Kazarian Jingjun Xu Roberto Morandotti Zhigang Chen 2019Light(Science & Applications)2019,8,1:3
6Quantitative analysis of opioids and cannabinoids in wastewater samples显示文摘Wastewater-based epidemiology is an innovative approach that uses the analysis of human excretion products in wastewater to obtain information about exposure to drugs in defined population groups.We developed and validated an analytical method for the simultaneous determination of opioids(morphine,oxycodone,hydrocodone,oxymorphone and hydromorphone),and cannabinoids(△9-tetrahydrocannabinol,11-nor-9-carboxy-tetrahydrocannabinol(THCCOOH)and THCCOOH-glucuronide)in raw-influent wastewater samples by ultra-high performance liquid chromatography-tandem mass spectrometry.Method validation included linearity(5-1000 ng/L for opioids,10-1000 ng/L for cannabinoids),imprecision(<21.2%),accuracy(83%-131%),matrix effect(from-35.1%to-14.7%)and extraction efficiency(25%-84%),limit of detection(1-5 ng/L)and quantification(5-10 ng/L)and auto-sampler stability(no loss detected).River and wastewater samples were collected in triplicate from different locations in New York City and stored at-20℃until analysis.Water from sewage overflow location tested positive for morphine(10.7 ng/L),oxycodone(4.2-23.5 ng/L),oxymorphone(4.8 ng/L)and hydromorphone(4.2 ng/L).Raw influent wastewater samples tested positive for morphine(133.0-258.3 ng/L),oxycodone(31.1-63.6 ng/L),oxymorphone(16.0-56.8 ng/L),hydromorphone(6.8-18.0 ng/L),hydrocodone(4.0-12.8 ng/L)and THCCOOH(168.2-772.0 ng/L).This method is sensitive and specific for opioids and marijuana determination in wastewater samples.Alethea Jacox Jillian Wetzel Shu-Yuan Cheng Marta Concheiro 2017Forensic Sciences Research2017,2,1:3
7Absence of the interstitial cells of Cajal in patients with gastroparesis and correlation with clinical findings显示文摘Jameson Forster Ivan Damjanov Zhiyue Lin Irene Sarosiek Paul Wetzel Richard W. McCallum 2005Journal of Gastrointestinal Surgery2005,,1:2
8Epoxy nanocomposites with high mechanical and tribological performance显示文摘Bernd Wetzel Frank Haupert Ming Qiu Zhang 2003Composites Science and Technology2003,,14:2
9食管肿瘤X线诊断的现状显示文摘传统X线检查方法能及时、无痛苦地诊断吞咽困难。X线诊断应在内窥镜检查前进行,因其病理结果对内窥镜的施行具有参考意义。低张双对比造影是一种重要的补充,而CT和磁共振对于术前肿瘤分期有重要意义。Max Georgi Hans-Peter Busch Rainer Simon Andre Sommer Eduard Wetzel 王天才 1992放射学实践1992,7,3:2
10Dynamic contrast enchanced T2*-weighted MR imaging of gliomatosis cerebri显示文摘Yang S Wetzel S Law M 2002AJNR2002,23,3:2
11An in vivo comparison of the potential for extravertebral cement leak after vertebroplasty and kyphoplasty 显示文摘Phillips PM Wetzel Todd F Lieberman I 2002Spine2002,27,19:1
12Sirolimus-associated heavy proteinuria in a renal transplant recipientevidence for a tubular mechanism显示文摘Straathof-Galema L Wetzels JF Dijkman HB 2006Am J Transplant2006,6,2:1
13Mitochondrial cytochrome release in apoptosis occurs upstream of DEVD -specfic caspase activation and independently of mitochondrial transmembrane depolarization 显示文摘Bossy Wetzel E Neweoeyer DD Green DR 1998EMBO J1998,17,:1
14Attempts to obtain reosseointegration following experiment peri-implantitis in dog显示文摘Wetzel AC Vlassis J Caffesse RG 1999Clin Oral Implants Res1999,10,2:1
15Imaging of the intracranial venous system with a contrast-enhanced volumetric interpolated examination显示文摘Wetzel SG Law M Lee VS 2003Eur Radiol2003,1395,:1
16Dynamic contrast-enhanced T2-weighted MR imaging of gliomatosis cerebri显示文摘Yang S Wetzel S Law M 2002Am J Neurcradioi2002,23,3:1
17Multiple roles for MMPs and TIMPs in cerebral ischemia 显示文摘Cunningham LA Wetzel M Rosenberg GA 2005Glia2005,50,:1
18Epoxy nanocomposites-fracture and toughening mechanisms显示文摘Wetzel B Rosso P Haupert F 2006Engineering Fracture Mechanics2006,73,16:1
19Imaging of the intracraniaI venous system with a contrast-enhanced volumetric interpolated examination显示文摘Wetzel S G Law M Lee V S 2003Eur Radiol2003,13,5:1
20Marketing service relationships:the role o commitment显示文摘WETZELS MARTIN KO DE RUYTER MAMXL VANBIRGELEN 1998Journal of business and industrial market ing1998,,45:1
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