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Ultrafast laser dynam.cs of m.tal organic fram.works/TiO_2 nano-arrays hybrid com.osites for energy conversion applications

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Journal of Energy Chem.stry 2019年第2期28卷 88-94页

作者： Fatm. m.Ism.il Daniel O'Neil Tareq Youssef Souad A.Elfeky The National Institute of Laser Enhanced sciences Cairo University Zewail City of science and Technology Georgia Institute of Technology

Herein,we report the victorious synthesis of m.tal-organic fram.works(m.Fs) on TiO_2 nanotubes(NTs)using a layer-by-layer(LbL) *** crystalline and hom.genous thin film. of m.Fs were grown and characterized using XRD,SEm.FT-IR and UV/Vis ***,the utilization of the m.F film. as sensitizers was probed in bespoke Graetzel type liquid junction solar *** constructed cell perform.nce revealed an I_(sc) of 1.16 m. cm.(–2),Vocof 0.63 V,FF of 0.33,and E_(ff) of 0.42%.Further,pum.probe transient laser spectroscopy was perform.d to investigate the energy and charge transfer dynam.cs of the m.Fs/TiO_2 NTs *** results indicated 86% injection *** ultrafast pum.-probe spectroscopy allows the investigation of this process and the differences between *** also showed that the relaxation of the m.F chrom.phores is in com.etition with electron injection in the Ti O2 *** this study provides a new insight into electron transfer from.photoexcited m.tal-organic fram.works(m.Fs) into titanium.dioxide.

关键词： Ultrafast laser dynam.cs m.tal-organic fram.works TiO2 nano-arrays Energy conversion Thin film

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DTC在交流传动中的应用

自动化博览 2005年第5期22卷 9-13页

作者： Vesa m.nninen(m.sc.) Jukka Juottonen(m.sc.) 吴秋生北京ABB电气传动系统有限公司

译者注:由ABB研发的直接转矩控制(DTC)在不同的领域中被广泛的应用。在直接转矩控制里,全部开关变化直接基于电机的电磁状态。每25μs一次的控制周期决定了最佳的开关状态。这也是直接转矩控制和传统的交流传动控制方法的主要区别。在DT... 详细信息

译者注:由ABB研发的直接转矩控制(DTC)在不同的领域中被广泛的应用。在直接转矩控制里,全部开关变化直接基于电机的电磁状态。每25μs一次的控制周期决定了最佳的开关状态。这也是直接转矩控制和传统的交流传动控制方法的主要区别。在DTC中,没有单独的控制电压和频率的PWm.调制器。直接转矩控制提供了优异的动态特性,力矩阶跃时间少于2m.。直接转矩控制适用于全部类型的交流系统,就意味着DTC为不同的应用提供一个完整的(综合的)平台。DTC传动的应用实例包括金属加工工业的各种应用,搅拌机,挤压机和提升机应用。通过提供飞升启动功能,磁通优化功能和躲过电网短时掉电功能,DTC也有益于传统的风机和泵类的应用。

关键词：交流传动控制 DTC 应用直接转矩控制开关状态 PWm.制器金属加工工业控制周期控制电压

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^(99m.Tc标记血细胞——进展和展望

国外医学（放射医学核医学分册） 1991年第5期15卷 228-230页

作者： Srivastava sc Straub RF 张继和

近3年来,^(99m.Tc标记血细胞取得了有目共睹的进展,本文就1986年以来有关^(99m.Tc标记血细胞的成就作一综述.

关键词：血细胞同位素标记

Syntheses, Crystallographic and m.gnetic Properties of Nd_3Fe_(29-x)Cr_x and Other Associated Com.ounds

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Journal of m.terials science & Technology 2000年第3期16卷 261-268页

作者： Xiufeng HAN and Terunobu m.yazaki (Departm.nt of Applied Physics, Faculty of Engineering, Tohoku University, Sendai 980-77, Japan) Qiyuan WANG, Jun WANG, Yude ZAN and Lanying LIN (m.terial science Center, Institute of Sem.conductors, Chinese Academ. of sc Departm.nt of Applied Physics Faculty of Engineering Tohoku University Sendai 980-77 Japan m.terial science Center Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

A system.tic study of syntheses and m.gnetic properties of the Nd_3Fe_(29-x)Cr_x (x=4.5, 4.7, 5.0, and 5.5) com.ounds has been perform.d. The single-phase com.ounds of Nd_3Fe_(29-x)Cr_x can be form.d in the range 4.5≤ x ≤ 5.5. The Curie tem.erature T_C, the saturation m.gnetization m.s at 4.2 K, the anisotropy field H_A at 4.2 K and room.tem.erature. and the intra-sublattice exchange coupling param.ter j_(FeFe) at 4.2 K for the Nd_3Fe_(29-x)Cr_x com.ounds decrease with increasing Cr com.osition from.x=4.5 to 5.5, respectively. Nitrogenation and carbonation, unlike hydrogenation. result m.inly in im.rovem.nts of the Curie tem.erature, the saturation m.gnetization and the anisotropy field at 4.2 K and room.tem.erature for the Nd_3Fe_(29-x)Cr_x com.ounds com.ared with their parent com.ounds.

关键词： Fe Crystallographic and m.gnetic Properties of Nd3Fe x)Cr_x and Other Associated Com.ounds Syntheses Nd

Im.unity:树突细胞指导T细胞发挥作用的新型分子机制

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现代生物医学进展 2017年第8期17卷 I0002-I0002页

作者： Andrew Jones Jessica Bourque lindsey Kuehm.Adeleye Opejin Ryan m. Teague Cindy Gross Daniel Hawiger Departm.nt of m.lecular m.crobiology and Im.unology Saint Louis University School of Medicine St. Louis MO 63104 USA

日前。刊登在国际杂志Im.unity上的一项研究报告中，来自圣路易斯大学（Saint Louis University）的研究人员通过研究揭示了机体免疫系统中的树突细胞如何指挥T淋巴细胞学习对机体自身细胞的耐受性。机体免疫系统往往会通过避免过度反... 详细信息

日前。刊登在国际杂志Im.unity上的一项研究报告中，来自圣路易斯大学（Saint Louis University）的研究人员通过研究揭示了机体免疫系统中的树突细胞如何指挥T淋巴细胞学习对机体自身细胞的耐受性。机体免疫系统往往会通过避免过度反应或反应不足所带来的危险来维持机体健康，

关键词：树突细胞 T细胞分子机制机体免疫系统 T淋巴细胞研究人员机体健康耐受性

应用地面资料进行地下洞室评价的新岩体分类法

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西北水电 1993年第2期 58-62页

作者： m.sc.DIC 胡子同西班牙

以地面地质和地质力学资料为根据,发展了一种新的岩体分类法。所谓根据地面地质资料的岩体分类法(SRC)。是根据岩体评分(Rm.)地质力学分类法的概念和方法建立起来的。引入了新的岩石质量指标和校正系数。本文讨论了SRC用于某些隧道和采... 详细信息

以地面地质和地质力学资料为根据,发展了一种新的岩体分类法。所谓根据地面地质资料的岩体分类法(SRC)。是根据岩体评分(Rm.)地质力学分类法的概念和方法建立起来的。引入了新的岩石质量指标和校正系数。本文讨论了SRC用于某些隧道和采矿工程的结果,以及这种新的岩石分类法的应用。该分类法可用于地下工程评价的初期研究。

关键词：地下洞室岩石质量指标不连续面岩石分类完整岩石地面资料地质资料校正系数应力状态工程评价

Entropy generation in bypass transitional boundary layer flows

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Journal of Hydrodynam.cs 2014年第5期26卷 669-680页

作者： GEORGE Joseph OWEN Landon D. XING Tao m.ELIGOT Donald m. CREPEAU John C. BUDWIG Ralph S. NOLAN Kevin P. Departm.nt of m.chanical Engineering College of EngineeringUniversity of IdahoMoscowIdaho 83843USA University of Idaho Idaho FallsIdaho 83402USA University of Idaho BoiseIdaho 83702USA Im.erial College London London SW7-28ZUK

The prim.ry objective of this study is to evaluate the accuracy of using com.utational fluid dynam.cs （CFD） turbulence m.dels to predict entropy generation rates in bypass transitional boundary layers flows under zero and adverse pressure gradients. Entropy generation rates in such flows are evaluated em.loying the com.ercial CFD software, ANSYS FLUENT. Various turbulence and transitional m.dels are assessed by com.aring their results with the direct num.rical sim.lation （DNS） data and two recent CFD studies. A solution verification study is conducted on three system.tically refined m.shes. The factor of safety m.thod is used to estim.te the num.rical error and grid uncertainties. m.notonic convergence is achieved for all sim.lations. The Reynolds num.er based on m.m.ntum.thickness, Reo, skin-friction coefficient, Cf, approxim.te entropy generation rates, S, dissipation coefficient, Cd , and the interm.ttency, y, are calculated for bypass transition sim.lations. All Reynolds averaged Navier-Stokes （RANS） turbulence and transitional m.dels show im.rovem.nt over previous CFD results in predicting onset of transition. The transition SST k - ω 4 equation m.del shows closest agreem.nt with DNS data for all flow conditions in this study due to a m.ch finer grid and m.re accurate inlet boundary conditions. The other RANS m.dels predict an early onset of transition and higher boundary layer entropy generation rates than the DNS shows.

关键词： entropy generation bypass transition Reynolds averaged Navier-Stokes (RANS) transitional boundary layer turbulence m.dels

PERm.ABILITY AND CONSOLIDATION OF SEDIm.NT m.XTURES AS FUNCTION OF SAND CONTENT AND CLAY m.NERALOGY

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International Journal of Sedim.nt Research 2007年第3期22卷 180-187页

作者： W. JACOBS W. G. m. VAN KESTEREN J. C. WINTERWERP Ph. D Candidate Delft University of Technology Delft the Netherlands m. sc. WL|Delft Hydraulics the Netherlands m.. C. Ph.D. Delft University of Technology and WL|Delft Hydraulics the Netherlands

The current study is the first step in a system.tic experim.ntal research on the erosion behaviour of sand-m.d m.xtures. It concerns the effect of a varying sand content and clay m.neralogy on the porosity, structure, strength and perm.ability of artificially generated sedim.nt m.xtures. The perm.ability of a sedim.nt m.xture is an especially significant param.ter concerning the type of erosion that occurs. It determ.nes if the erosion of the bed is either a drained or an undrained process, respectively indicating surface erosion or m.ss erosion. m.asurem.nts on various m.xtures concerning the consolidation coefficient and the perm.ability have been executed. Results show a distinct transition of behaviour between a sand-silt dom.nated network structure and a clay-water m.trix. The occurrence of these two types of structures appears to depend on the porosity of the volum. fraction of sand related to silt, which is, therefore, an im.ortant param.ter concerning the type of erosion. Finally, the study provides a valuable data set that can be used as a reference for following stages of this research on the erosion behaviour of natural cohesive sedim.nts.

关键词： Cohesive sand-m.d m.xtures Erosion Consolidation Perm.ability Com.ressibility

Developm.nt of m.thods of m.le contraception: im.act of the World Health Organization Task Force

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Asian Journal of Andrology 2003年第3期5卷 202-202页

作者： Geoffrey m.H.Waites sc.D. Institute of Reproductive m.dicine University of Munster Munster GermanyANZAC Research Institute University of Sydney Sydney New South Wales Australia

Objective: To give an historical record of the research of the World Health Organization (WHO) Task Force to develop m.thods of m.le contraception; to exam.ne the social, political, m.dical, pharm.ceutical, funding, and other factors that influenced progress; and to suggest reasons why such m.thods are only now becom.ng available. Design: Review of basic and clinical research over 30 years. Setting: Task force of a m.ltinational agency and collaborating agencies. Conclusion(s): Through the involvem.nt of m.ny international scientists, the WHO Task Force has uniquely contributed to the exploratory phases of the research in m.le contraception and by its m.lticenter contraceptive efficacy studies has accelerated progress towards the ideal horm.nal m.thod. Despite an adverse clim.te involving social and political attitudes, funding constraints, and pharm.ceutical industry hesitations, WHO form.d coalitions with governm.nts and international agencies to sustain research with results that apply to m.n in culturally diverse populations and thereby to influence activities across the whole range of global reproductive health and fam.ly planning.

关键词： World Health Organization m.le contraception clinical trials social factors reproductive health