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Valence Change and Luminescence of Divalent Samarium in Strontium Borates

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Journal of Materials Science & Technology 1999年第5期15卷 449-452页

作者： Qinghua ZENG Zhiwu PEI Shubing WANG and Qiang SU(Laboratory of Rare Earth Chemistry and Physics, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, China) To whom correspondence should be addressedE-mail: zengqh@ns. Laboratory of Rare Earth Chemistry and Physics Changchun Institute of Applied Chemistry Chinese Academy of Sciences Changchun 130022 China Laboratory of Excited State Processes Chinese Academy of Sciences Changchun 130022 China

The valence change of samarium from trivalent to divalent state in strontium borates (SrB6O10)prepared in air was observed. The high resolution spectra of Sm2+ in matrix were studied between 10 K and 300 K. The results showed that three crystallographic sites for Sm2+ were available in the host. Energy transfer among these sites was possible. The vibronic transition of 5D0-7f0 of Sm2+ was studied at room temperature and the Huang-Rhys factor S was calculated. Due to the thermal population, 5D1 -7f0 transition at room temperature was observed

关键词： fJ cm nm

Momentum and heat transfer of a special case of the unsteady stagnation-point flow

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Applied Mathematics and Mechanics(English Edition) 2020年第1期41卷 51-82页

作者： T.G.fANG f.J.WANG Mechanical and Aerospace Engineering Department North Carolina State University

This paper investigates the unsteady stagnation-point flow and heat transfer over a moving plate with mass transfer,which is also an exact solution to the unsteady Navier-Stokes(ns)*** boundary layer energy equation is solved with the closed form solutions for prescribed wall temperature and prescribed wall heat flux *** wall temperature and heat flux have power dependence on both time and spatial *** solution domain,the velocity distribution,the flow field,and the temperature distribution in the fluids are studied for different controlling *** parameters include the Prandtl number,the mass transfer parameter at the wall,the wall moving parameter,the time power index,and the spatial power *** is found that two solution branches exist for certain combinations of the controlling parameters for the flow and heat transfer *** heat transfer solutions are given by the confluent hypergeometric function of the first kind,which can be simplified into the incomplete gamma functions for special *** wall heat flux and temperature profiles show very complicated variation *** wall heat flux can have multiple poles under certain given controlling parameters,and the temperature can have significant oscillations with overshoot and negative values in the boundary *** relationship between the number of poles in the wall heat flux and the number of zero-crossing points is *** difference in the results of the prescribed wall temperature case and the prescribed wall heat flux case is *** given in this paper provide a rare closed form analytical solution to the entire unsteady ns equations,which can be used as a benchmark problem for numerical code validation.

关键词： unsteady stagnation point flow Navier-Stokes(ns)equations analytical solution heat transfer

Brugada syndrome masquerading as acute myocardial infarction in a patient presenting with ventricular fibrillation

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中华医学杂志(英文版) 2002年第3期 139-141页

作者： Ngai-shing MOK and Yuen-choi CHOI Cardiology Team, Department of Medicine & Geriatrics, Princess Margaret Hospital , Hong Kong, China (Mok ns and Choi YC)

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无需跟踪的场景事件识别(英文)

自动化学报 2003年第3期29卷 321-331页

作者： Shaogang Gong Tao Xiang (Department of Computer Science, Queen Mary, University of London, London E1 4ns, U.K.) Department of Computer Science Queen Mary University of London London E1 4NS 英国

提出了一种用于视觉监控中行为识别的新颖方法 .该方法将相应于目标行为的场景事件建模为一组使用PCH (PixelChangeHistories)检测的自治像素级事件 .结合基于改进的MDL(MinimumDescriptionLength)的自动模型规则选择 ,EM (Expectation ... 详细信息

提出了一种用于视觉监控中行为识别的新颖方法 .该方法将相应于目标行为的场景事件建模为一组使用PCH (PixelChangeHistories)检测的自治像素级事件 .结合基于改进的MDL(MinimumDescriptionLength)的自动模型规则选择 ,EM (Expectation Maximisation)算法被采用来聚类这些像素级的自治事件成为语义上更有意义的区域级的场景事件 .该方法是计算上有效的。

关键词：场景事件识别行为识别视觉监控自治像素级事件计算机

Bioinformatic screening of the binding transcription sites in the regulatory regions of genes up-regulated in response to oxidative stress

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Open Journal of Genetics 2012年第4期2卷 1-4页

作者： Shkurat TP Ponomareva ns Aleksandrova AA Shkurat MA Butenko AI Panich AE Southern federal University Rostov-on-Don Russia

This study focuses on bioinformatics search for new regulatory structures in the non-coding DNA, located around the patterns of gene expression levels changed significantly in response to oxidative stress. Hypothesized that all of the genes increase the expression in response to oxidative stress may have the same motifs in non-coding DNA. To search for motifs created an integrated collection database of transcription binding sites - JASPAR, TRAnsfAC, Hocomoco Tf Homo sapiens, Uniprobe Tf Mus musculus. Two types of regulatory regions: the promoter region and the sequence with the capture of potential cis-regulatory modules. In the regulatory regions of genes increase the expression in response to oxidative stress, in contrast to the gene expression level did not change, families of transcription factors identified SOX (1-30) and HX (A, B, C, D).

关键词： Gene Expression DNA Microarrays Noncoding DNA Oxidative Stress Transcription factor Sites of Transcription factor Binding DNA Motif

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汽车LED照明系统的挑战与解决方案

世界电子元器件 2009年第7期 50-53页

作者： ns公司 ns公司

在线座谈(Online Seminar)是中电网于2000年推出的创新服务,通过"视频演示+专家解说+在线问答"三位一体相结合的形式,充分发挥网络平台的便捷性,实现了先进半导体技术提供商与系统设计工程师的实时互动交流,其形式和内容都广受电子行业... 详细信息

在线座谈(Online Seminar)是中电网于2000年推出的创新服务,通过"视频演示+专家解说+在线问答"三位一体相结合的形式,充分发挥网络平台的便捷性,实现了先进半导体技术提供商与系统设计工程师的实时互动交流,其形式和内容都广受电子行业工程师的好评。本刊每期将挑选一些精华内容整理成文,以飨读者。欲了解更多、更详细的内容,敬请登录http://***。

关键词： LED照明系统汽车头灯转向信号灯钨丝灯泡高亮度汽车照明刹车灯倒车灯

Eurasia as the scene of the Late Cenozoic tectogenesis

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Geoscience frontiers 2012年第5期3卷 559-569页

作者： G.f.Ufimtsev Institute of the Earth's Crust SB RAS Irkutsk 664033Russia

This paper attempts to review the descriptions on the genetic series of neotectonic forms in Eurasia. Morphotectonically, the Eurasian continental block exhibits a radial-concentric pattern consist- ing of four kinds of tectonic units： platforms, rejuvenated and youthful mobile belts, and the continent- ocean transition zones. Vast areas of young and ancient platforms, such as Siberia, have experienced slow-rate Late-Cenozoic uplift and little interior deformation. The youthful orogenic belts are clustered into the giant Alpine-Himalayan megabelt. The rejuvenated mountain belts are characterized by a variety of structural-morphological types of orogens, such as domelike uplifts, block uplifts and intermountain basins. The continent-ocean transition zones in Eastern Asia, including marginal rifts and extensional basins, are resulted from interaction between the continental block and Pacific Ocean and Philippine Sea since the Late Cenozoic. One of the conspicuous features of Eurasia is that most areas lie in the largest geoid depression of the Earth, and the ns trending Uralian-Oman lineament expresses a break on the geoid slope, implying a relationship to deep structure, including density inhomogeneities, down- ward to the core-mantle interface. Besides, the Eurasian continent fully demonstrates morphotectonic and recent geodynamic features of the Northern Hemisphere of the Earth, just in contrast to that of the Southern Hemisphere. It is best to view the surface morphotectonics and deep structure of the Earth as a geodynamic ensemble which has spawned the large-scale geomorphic features on the surface.

关键词： Morphotectonics Tectonic units Geoid Geodynamic ensembleEurasia

Stable non-synonymous substitutions on ns gene (ns1 and ns2 proteins) of Qinghai lake H5N1 influenza virus (Clade 2.2) after successive passages in Muscovy ducks

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Science China(Life Sciences) 2009年第9期52卷 847-853页

作者： GAO George f. Key Laboratory of Pathogenic Microbiology and Immunology of CAS (CASPMI) Institute of Microbiology Chinese Academy of Sciences (CAS) China-Japan Joint Laboratory of Molecular Immunology and Molecular Microbiology Institute of Microbiology Chinese Academy of Sciences Graduate University of Chinese Academy of Sciences Beijing Institutes of Life Science Chinese Academy of Sciences

Although worldwide concern has been raised since the large-scale outbreak of highly pathogenic avian influenza in wild birds at Qinghai Lake,China in 2005,the factors responsible for the ability to kill waterfowl remain unclear. The why and how questions of the H5N1 virus species-jump into its reservoir host need to be answered. In this report we test the pathogenicity and adaptation of Qinghai Lake (Clade 2.2) isolate to Muscovy ducks for further understanding of this virus. The isolate was highly pathogenic in ducks and retained its high pathogenicity even after 20 generations of passage in ducks. During the process of serial passages,only the ns gene developed non-synonymous substitutions,which caused two mutations in ns1 protein (Val23Ala and Leu207Pro) and one in ns2 (Phe55Leu). These mutations persisted immutably through all subsequent passages and the pathogenicity remained high,implying that highly pathogenic H5N1 virus remains stable in aquatic birds through oral transmission. Although the exact functions of these mutations are not known,our results provide an important foundation for further understanding the characteristics of the Qinghai Lake isolates.

关键词： avian influenza virus H5N1 mutation ns1/2 serial passages

SIMPLE SWITCHER易电源产品系列及电源模块

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世界电子元器件 2011年第5期 50-54页

作者： ns公司 ns公司

在线座谈（Online Seminar）是中电网于2000年推出的创新服务,通过＂视频演示＋专家解说＋在线问答＂三位一体相结合的形式,充分发挥网络平台的便捷性,实现了先进半导体技术提供商与系统设计工程师的实时互动交流,其形式和内容都广受电... 详细信息

在线座谈（Online Seminar）是中电网于2000年推出的创新服务,通过＂视频演示＋专家解说＋在线问答＂三位一体相结合的形式,充分发挥网络平台的便捷性,实现了先进半导体技术提供商与系统设计工程师的实时互动交流,其形式和内容都广受电子行业工程师的好评。本刊每期将挑选一些精华内容整理成文,以飨读者。欲了解更多、更详细的内容,敬请登录http：//***。

关键词： SIMPLE 电源模块设计工程师品系半导体技术创新服务网络平台互动交流