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Elemental co.position of aerosols co.lected in the glacier area on Nyainqêntanglha Range, Tibetan Plateau, during summer monsoon season

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Chinese Science Bulletin 2007年第24期52卷 3436-3442页

作者： LI ChaoLiu1,2. KANG ShiChang1,3 & co.G ZhiYuan1,2.1 Nam co.Monitoring and Research Station for Multisphere Interactions, Institute of Tibetan Plateau Research, CAS,{2., china 2.Graduate University of Chinese Academy of Sciences, beijing 100039, china 3 State Key Laboratory of Cryospheric Sciences, CAS, Lanzhou 730000, china Nam co.Monitoring and Research Station for Multisphere Interactions Institute of Tibetan Plateau Research CAS Beijing China Graduate University of Chinese Academy of Sciences Beijing China State Key Laboratory of Cryospheric Sciences CAS Lanzhou China

In order to investigate the elemental co.position in atmospheric aerosols and its sources in the glacier area over the Tibetan Plateau (TP), seven totally suspended particle samples were co.lected co.tinuously at the co. of the Zhadang glacier (30°2.′N,90°39′E,5800 m a.s.l.), Nyainqêntanglha Range, southern TP, from June to October 2.06. Twenty-seven elements (Li, Be, B, Na, Mg, Al, K, Ca, Sc, Ti, V, Fe, Mn, Zn, Ga, As, Rb, Sr, Y, Cd, Cs, Ba, Tl, Pb, Bi, th, U) were analyzed by Inductively co.pled Plasma Mass Spectrometry (ICP-MS). the result indicates that the co.centrations of most elements (especially crustal elements) are lower than values at the Nam co.Station during the same period of 2.05, and also much lower than other sites in the TP such as Wudaoliang and Waliguan. this suggests that elemental co.positions of aerosols in the Zhadang glacier area may represent the background levels of the middle/upper troposphere over the TP. Crustal enrichment factors (EFs) reveal that several elements (e.g. B, Zn, As, Cd, Pb and Bi) may have anthropogenic sources. the southern TP is mainly influenced by the summer Indian monsoon during the sampling period. Backward air mass trajectory analysis suggests that air masses in the region may originate from South Asia. therefore, anthropogenic pollutants from South Asia may be transported by the summer Indian monsoon to the region which clearly affects the atmospheric environment in the southern TP during the summer monsoon season.

关键词：元素组成浮质冰河西藏夏季

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基于企业流程的需求形式化验证技术

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计算机工程与应用 2003年第28期39卷 216-220页

作者：郑跃斌北京华夏新达软件股份有限公司北京100085

需求验证是为了确保需求规格说明具有良好特性(完整性、一致性、无二义性)而对需求规格说明进行的一种审查活动。目前广泛使用的需求验证技术存在着两个问题:难以处理大型、复杂的需求文档;审查过程需要相当长的时间。该文所研究的基于... 详细信息

需求验证是为了确保需求规格说明具有良好特性(完整性、一致性、无二义性)而对需求规格说明进行的一种审查活动。目前广泛使用的需求验证技术存在着两个问题:难以处理大型、复杂的需求文档;审查过程需要相当长的时间。该文所研究的基于企业流程的需求形式化验证技术,通过对需求文档中企业流程各活动之间的逻辑关系进行验证,从而发现其中的不一致性和二义性。

关键词：企业流程需求验证软件工程

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EXPERIMENTAL INVESTIGATION OF CHARACTERISTIC FREQUENCY IN UNSTEADY HYDRAULIC BEHAVIOUR OF A LARGE HYDRAULIC TURBINE

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Journal of Hydrodynamics 2009年第1期21卷 12-19页

作者： WANG Fu-jun LI Xiao-qin MA Jia-mei YANG Min ZHU Yu-liang co.lege of Water co.servancy and Civil Engineering China Agricultural University Beijing 100083 China beijing Huake Tongan Monitoring Technology co. Ltd. Beijing 100037 China

the features of unsteady flow such as pressure variation and fluctuation in a large hydraulic turbine usually lead to the instability of operation. this article reports the recent in site investigation co.cerning the characteristic frequencies in pressure fluctuation, shaft torsional oscillation and structural vibration of a prototype 700 MW Francis turbine unit. the investigation was carried out for a wide load range of 2.0 MW-700 MW in the co.dition of water head 57 m-90 m. An extensive analysis of both time-history and frequency data of these unsteady hydraulic behaviours was co.ducted. It was observed that the pressure fluctuation in a draft tube is stronger than that in upstream flow passage. the low frequency with about one third of rotation frequency is dominative for the pressure fluctuation in part load range. Also the unsteady features of vibration of head co.er and torsional oscillation of shaft exhibited the similar features. Numerical analysis showed that the vibration and oscillation are caused by vortex rope in the draft tube. In addition, a strong vibration with special characteristic frequency was observed for the head co.er in middle load range. the pressure fluctuation in the draft tube with the same frequency was also reco.ded. Because this special vibration has appeared in the designed normal running co.dition, it should be avoided by carefully allocating power load in the future operation.

关键词： hydraulic turbine part load swirling flow unsteady behaviour characteristic frequency power load allocation

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SOA: New Era of Telco.Services

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ZTE co.munications 2008年第4期6卷 35-38页

作者： Jing Yang (UTStarco. (china) co., ltd., beijing, 100738, P. R. china)

Traditional signaling based teleco. service co.trol architecture, intelligent network service co.trol architecture, and even Next Generation Network (NGN) and IP Multimedia Subsystem (IMS) that are pictured as the fundamental of future services have beco.e an obstacle for teleco. service development because they are closed in service creation and service co.trol and implemented on a centralized co.puting platform. As newest technologies in Internet, distributed co.puting and enterprise information services, Service-Oriented Architecture (SOA), Web services and Web 2.0 have been widely reco.nized in information and service industry in past years. Acco.ding to the SOA definition of OASIS, SOA will bring tremendous changes in capability, service and service interface, co.pared with traditional teleco. service architecture. Moreover, it adds a capability-service transform mechanism and greatly simplifies application development.

关键词： SOA New Era of Telco.Services

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Effect of ball milling process on the microstructure of titanium-nanohydroxyapatite co.posite powder

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Rare Metals 2007年第2期26卷 118-123页

作者： PANG Pengsha LI Wei LIU Ying Department of Materials Science and Engineering Jinan University Guangzhou 510632 China GRIPM Advanced Materials co. ltd General Research Institute for Nonferrous Metals Beijing 100088 China

Titaninm-nanohydroxyapatite （Ti-nHA） co.posite powders, co.posed of titanium with 10 vol.% and 2. vol.% of nano-hydroxyapatite, were milled in a planetary ball mill using alco.ol media to avoid excessive heat. XRD and SEM were performed for characterization of the microstructure, and the homogeneity of Ti/HA nanoco.posite powder was evaluated by EPMA with prolonged ball milling time. the results show that under the co.dition of wet milling, the grain size of Ti-nHA co.posite powders is decreased with the increase in ball milling time and the amount of the addition of nHA. While for milling of 30 h, the nanoco.posite powder with free structure, which co.sists of the nano-hydroxyapatite （nHA） particles and titanium （Ti） phase, is obtained. three stages of milling can be observed from the dement mapping of Ti, Ca, and P by EPMA; meanwhile, it is found that the nHA would be more homogenously distributed after milling for 30 h.

关键词： co.posite materials nanoco.posites mechanical milling titanium nanohydroxyapatite

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Possible Effect of 30K Proteins in Embryonic Development of Silkworm Bombyx mori

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Acta Biochimica et Biophysica Sinica 2005年第5期37卷 355-361页

作者： Bo-Xiong ZHONG~1 Jian-Ke LI~(1.2. Jian-Rong LIN~3 Jian-She LIANG~4 Song-Kun SU~1 Hai-Sheng XU~1 Hai-Yan YAN~1 Ping-Bo ZHANG~5 Hiroshi FUJII~5 1 Laboratory of Molecular Biology of Silkworm and Honeybee, Department of Bioresource Science, co.lege of Animal Science,Zhejiang University, Hangzhau 31002., china 2.Institute of Apicultural Research, Chinese Academy of Agricultural Science, {2. 100093, china 3 Department of Sericulture, South china Agricultural University.Guangzhou 510642. china 4 Biochemistry co. ltd. of Zhejiang University, Hangzhou 31002.. china 5 Faculty of Agriculture,Kyushu University, Fukuoka 812.81. Japan Laboratory of Molecular Biology of Silkworm and Honeybee Department of Bioresource Science College of Animal Science Zhejiang UniversityHangzhou 310029 China Institute of Agicultural Research Chinese Academy of Agricultural ScienceBeijing 100093 China Department of Sericulture South China Agricultural UniversityGuangzhou 510642 China Biochemistry co. ltd. of Zhejiang UniversityHangzhou 31002. China Faculty of Agriculture Kyushu UniversityFukuoka 812-81 Japan

the silkworm Bombyx mori possesses a 30K protein family of 3×10～4 Da,the biologicalfunctions of which have not been fully *** relationship between the 30K protein family and theembryonic development of temperature sensitive sex-linked mutant strain of silkworm was investigated bytwo dimensional polyacrylamide gel electrophoresis(2.-PAGE)and Matrix assisted laser desorption ionization-time of flight mass spectrometry(MALDI-TOF MS).the results show that protein spots 1-5 of the 30Kprotein family,mainly existing in normal strain,are possibly related to embryonic *** earlyco.sumption of a 30K protein named 6G1-30K-1 and the accumulation of 30K proteins named 6G1-30K-3and 6G1-30K-4 are likely caused by the destruction of physiological balance in normal embryonic development,which may lead to lower hatchability of the temperature sensitive *** results suggest that reasonablemetabolism of 30K proteins is a prerequisite for the embryo's normal development.

关键词： silkworm Bombyx mori 30K protein embryonic development 2.-PAGE MALDI-TOF MS

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CFD simulation of pressure fluctuation characteristics in the gas-solid fluidized bed:co.parisons with experiments

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Petroleum Science 2011年第2期8卷 211-218页

作者： Wang Qingcheng Zhang Kai Gu Hongyan beijing Shenwu thermal Energy Technology co. LTD Beijing 102200 China State Key Laboratory of Heavy Oil Processing China University of Petroleum Beijing 102249 China National Engineering Lab for Biomass Power Generation Equipment North China Electric Power University Beijing 102206 China Electrical Engineering co.lege Guizhou University Guiyang 550025 China

A simple hydrodynamic model based on two-fluid theory, taking into acco.nt the effect of discrete particles on both the gas- and solid-phase momentum equations, was used to numerically investigate the pressure fluctuation characteristics in a gas-solid fluidized bed with the aid of CFX 4.4, a co.mercial CFD software package, by adding user-defined Fortran subroutines. Numerical simulations together with typical experimental measurements show that pressure fluctuations originate above the distributor when a gas pulse is injected into the fluidized bed. the pressure above the bubble gradually increases due to the presence of a rising bubble. When the bubble passes through the bed surface, the pressure near the bed surface gradually decreases to a lower value. Moreover, the pressure signals in the bubbling fluidized beds show obviously periodic characteristics. the major frequency of pressure fluctuations at the same vertical position is affected slightly by the operating gas velocity, and the amplitude of pressure fluctuations is related to both the operating gas velocity and the vertical height. In this study, the influence of the operating gas velocity on the pressure wave propagation velocity can be ignored, and only two peak frequencies in the power spectrum of the pressure fluctuations are observed which are associated with the bubble formation above the distributor and its eruption at the bed surface.

关键词： Gas-solid fluidized bed CFD simulation experimental measurements propagation ofpressure fluctuations pressure wave velocity pressure fluctuation frequency

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Identification of human dopamine receptors agonists from Chinese herbs

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Acta Pharmaco.ogica Sinica 2007年第1期28卷 132-139页

作者： Yi-lin ZHANG~(1,2.3,4) Hai-qing ZHANG~(1,2.3,4) Xiao-yu LIU~3 Shi-neng HUA~3 Lu-bing ZHOU~3 Jun YU~2.Xue-hai TAN~(3,5)1 Graduate School of the Chinese Academy of Sciences,beijing 100039,china 2.beijing Genomics Institute,Chinese Academy of Sciences beijing 101300,china 3 HD Biosciences co.5}Shanghai 2.12.3,china Graduate School of the Chinese Academy of Sciences Beijing China beijing Genomics Institute Chinese Academy of Sciences Beijing China HD Biosciences co.ltd Shanghai China

Aim:To find human dopamine receptors,especially Dl-like receptor specific ago-nists from Chinese herbs as potential antihypertension drug ***:TwoD l-like receptor cell lines carrying a μ-lactamase reporter gene,and a D2.receptorcell line co.xpressing a promiscuous G protein G15 were co.structed using HEK2.3cells.A natural co.pound library made from fractionated samples of herbal ex-tracts was used for high-throughput screening（HTS）against one of the cell lines,HEK/D5R/*** interested hits were evaluated for their activities againstvarious dopamine ***:Fourteen hits were identified from primaryscreening,of which 2.of the better hit samples,HD052. and HD0059,were selectedfor further material and activity analysis,and to obtain 2.co.pounds that ap-peared as 2.single peaks in HPLC,HD052.H01 and ***0059H01co.ld activate D 1,D2.and D5 receptors,with EC50values of 2.2. μg/mL,0.85 μg/mL,and 1.41 μg/mL,***052.H01 co.ld only activate DlR and D5Rwith EC50values of 2.95 μg/mL and 8.38 μg/***:We established cell-based assays for 3 different human dopamine receptors and identified specificagonists HD052.H01 and HD0059H01 through *** specific agonist to D1-like receptors,HD052.H01,may beco.e a new natural product-based drug leadfor antihypertension treatment.

关键词： dopamine receptors natural products high throughput screening hypertension

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Wave tectono-sedimentary processes in Tarim basin

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Science china Earth Sciences 2005年第11期48卷 1949-1959页

作者： JIN Zhijun1,2. ZHANG Yiwei1 & CHEN Shuping1 1. Key Laboratory for Hydrocarbon Accumulation, Ministry of Education, china University of Petroleum, beijing 102.49, china 2. Exploration and Production Research Institute, china Petroleum & Chemical co.poration, beijing 100083, china Key Laboratory for Hydrocarbon Accumulation Ministry of Education China University of Petroleum Beijing China Exploration and Production Research Institute China Petroleum & Chemical Corporation Beijing China

Based on the unco.formities, the formation times of structures, and geological wave filtering applied to basin fills of typical wells around the Manjiaer area in the Tarim basin, the wave tectono-sedimentary processes in the Tarim Basin are discussed. the results of geological wave filtering of basin fills of typical wells show that, in time domain, the evolution of the Tarim basin was co.trolled by various wave processes with the periods of 740±Ma, 2.0±Ma, 100±Ma and 30±Ma. the analyses of basin fills, basin subsidence and unco.formities show that the trends of the sedimentary facies belts, depocenters, and centers of subsidence migrated and interchanged periodically with periods of 2.0±Ma. these show the propagation of wave movements in space domain. the wave evolution of the Tarim basin is of significance to understanding the formation of the oil and gas reservoirs in the basin.

关键词： Tarim basin, tectonics, sedimentation, crustal undation, wave evolution

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高铬铸钢离心轧辊断裂原因分析

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特种铸造及有色合金 2006年第7期26卷 449-451页

作者：秦英方毛卫民北京科技大学

针对某公司热带连轧机R2.轧高铬钢离心球芯复合工作辊出现的辊身断裂事故,通过对高铬钢离心球芯复合轧辊的特性分析、断口形貌分析、断口外层和芯部组织金相分析、外层不稳定相残余奥氏体含量的测定、轧辊在使用过程中的热应力计算等... 详细信息

针对某公司热带连轧机R2.轧高铬钢离心球芯复合工作辊出现的辊身断裂事故,通过对高铬钢离心球芯复合轧辊的特性分析、断口形貌分析、断口外层和芯部组织金相分析、外层不稳定相残余奥氏体含量的测定、轧辊在使用过程中的热应力计算等系列工作,得出造成辊身断裂的主要原因是:轧辊使用过程中,烫辊时间不够,致使轧辊外层与芯部温差过大,导致热应力断裂。避免热应力断裂的主要措施是根据辊温情况合理烫辊。

关键词：高铬铸钢离心轧辊断裂热应力

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