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World Journal of Gastroenterology 2000年第5期6卷 738-741页

作者： Chen YP liang WF zhang l He HT luo KX First Mil Med Univ Nanfang Hosp Dept Infect Dis Guangzhou 510515 Guangdong Provi Peoples R China

INTRODUCTIONAlthough several specific detecting methods hadbeen applied to determine the hepatitis virus,therewas a lot of cryptogenic hepatitis without anyknown hepatitis infectious *** of hepatitis G virus (HGV) (also knownas GB-C virus) infection has been reported to be 5%-13% in patients with non-A-E hepatitis andcirrhosis,however,there is little evidencesuggesting that HGV causes hepatitis in human.

关键词： transfusion-transmitted virus liver disease/etiology DNA virus polymerase chain reaction serodiagnosis hepatitis viruses

lactosamination of liposomes and hepatotropic targeting research

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World Journal of Gastroenterology 2000年第4期6卷 593-596页

作者： Chen YP zhang l lu QS Feng XR luo KX First Mil Med Univ Dept Infect Dis Nanfang Hosp Guangzhou Guangdong Prov Peoples R China

Site-specific delivery of therapeutic drugs to their target cells is a major scientific challenge for the pharmaceutical sciences. It offers a number of advantages over conventional drug administration. With drug targeting, high local concentrations of the drug can be achieved, thus circumventing many unwanted side effects. Various carriers have been suggested for the delivery of drugs, including liposomes[1 - 5] and (neo ) glycoproteins[6-8]. The asialoglycoprotein receptor (ASGP-R) has frequently been utilized for targeting drugs to the parenchymal liver cell[6- 12]. liposomes have several advantageous characteristics as drug carrier, and particularly, ligandtacked liposomes achieve a highly effective targeting[13]. Hara et al reported that asialofetuin (AF)-tacked liposomes distributed to rat hepatocytes selectively in vivo[14], and ASGP-R mediated the uptake of AF-liposomes encapsulating IFN-γ by isolated rat hepatocytes in vitro[15]. lactosaminated human serum albumin (l-HSA) is a neoglycoprotein taking number of galactose residue as terminal sugar[6].

关键词： liposomes asialoglycoprotein liver interferon-alpha antigens viral drug carriers drug therapy rats

Quantitative assessment of gas washing of oils in the Tazhong area of the Tarim Basin,Northwest China

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Science China Earth Sciences 2009年第1期52卷 12-21页

作者： YANG ChuPeng GENG AnSong lIAO ZeWen SUN YongGe zhang lüHui State Key laboratory of Organic Geochemistry Guangzhou Institute of GeochemistryChinese Academy of SciencesGuangzhou510640China Graduate University of Chinese Academy of Sciences Beijing 100049China

Gas washing has been known in the Tazhong area of the Tarim Basin,but its quantitative assessment has not yet been *** the influence of gas washing fractionation in the area was discussed based on the gas chromatogram data of 68 oils and the results of the mixing experiments of a black oil and a *** results show that the intensity of gas washing fractionation decreased generally from northern to southern part and vertically from deep reservoirs to shallow *** gas washing fractionation was mainly controlled by fault systems in this area,with the increase of n-alkane mass depletion positively correlated to the number and scale of *** washing fractionation appears to have affected the hydrocarbon property,and as a result the diversity of the crude oils is markedly controlled by gas *** addition,the occurrence of waxy oil in this area may be resulted from multiple factors including gas washing,mixed filling and migration fractionation.

关键词： gas washing n-alkane mole fraction n-alkane mass depletion Tazhong area Tarim Basin

A cceleration of Ionospheric Out-Flowing Ions in the Substorm in Geo-magnetotail

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Chinese Physics letters 1999年第12期16卷 908-910页

作者： SHI Jian-kui lIU Zhen-Xing T.l.zhang K.Torkar Center for Space Science&Applied Research Chinese Academy of SciencesBeijing 100080 Space Research Institute Austrian Academy of SciencesA-8010 GrazAustria

Using dynamics equation, acceleration of out-flowing ion during dipolarization in a substorm in the magneto-tail is simulated. The main results show that: (1) The ion distribution function that is initially exponentially decreasing with increasing speed is turned into a single peak distribution, and with time the peak moves towards higher speed. (2) The peak moves along V⊥ faster than that along V||, and the ion acceleration mainly occurs in the middle of the dipolarization. (3) The higher the initial energy, the faster the peak moves, and the more energy is obtained by the ions. The ion energy theoretically calculated is as high as about 102 keV, this is consistent with the observation.

关键词： storm faster acceleration

TRANSMISSION ElECTRON MICROSCOPY INVESTIGATIONS OF lOW-PRESSURE CVD GROWTH AND STRAIN RElAXATION OF Ge ISlANDS ON Si(110)

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Acta Metallurgica Sinica(English letters) 2005年第3期18卷 427-432页

作者： E.Spiecker l.zhang H.M.lu W.Jaeger l.Vescan MicroanalysisofMaterials FacultyofEngineeringChrisfian-Albrechts-UniversityKielKaiserstraβe224143KielGermany InstituteofThinFilmsandInterfaces ResearchCenterJiilichGmbH52425JiilichGermany

Shapes, dimensions, arrangements and the microstructure of self-assembled island s fabricated by low-pressure chemical vapour deposition (lPCVD) of Ge at 700℃ o nto Si(110) substrates have been investigated for different nominal Ge coverage by transmission electron microscopy (TEM) of plan-view and cross-section specime ns and have been compared with photoluminescence (Pl) measurements of Si-capped layer samples. The transition from the 2-dimensional layer to the 3-dimensional island growth mode takes place for a Ge deposition of nominally less than 2 mono layers. Upon this transition, many coherent islands and few larger islands with extended defects are observed. The coherent islands possess a dome-like shape an d lateral sizes up to 130nm. Photoluminescence spectra show island-related peaks whose energy positions are shifted towards lower energy with higher Ge coverage .

关键词： Si-Ge heteroepitaxy surface transmission electron microscopy Nanostructure

Influence of high configuration entropy on damping behaviors of Ti-Zr-Hf-Ni-Co-Cu high entropy alloys

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Journal of Materials Science & Technology 2023年第22期153卷 242-253页

作者： W.Q.Wu l.zhang K.K.Song J.M.Pelletier H.F.zhang J.C.Qiao School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710072China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Mechanical and Electrical Engineering Shandong UniversityWeihai 264209China Universitéde lyon MATEISUMR CNRS5510Bat.B.PascalINSA-LyonVilleurbanne Cedex F-69621France Chongqing Science and Technology Innovation Center of NPU Chongqing 401135China

TiNi-based shape memory alloys(SMAs)have been used as damping materials to eliminate noise and mechanical ***,their application is limited by low working temperatures and damping *** this work,two novel Ti-Zr-Hf-Ni-Co-Cu high entropy shape memory alloys(HESMAs)with different transformation temperatures and damping properties were *** results show that Ti_(25)Zr_(8)Hf_(17)Ni_(30)Co_(5)Cu_(15) has superior damping performance arising from martensitic transformation,shape memory effect(thermal cycle at constant load)as well as *** to traditional TiNi-based SMAs,the as-cast HESMAs exhibit a much higher ultrahigh yield strength(∼2 GPa)and storage modulus(∼50 GPa).The high configuration entropy of the HESMAs with high uneven internal stress and severe lattice distortion is revealed as the underlying mechanisms governing distinctive damping *** effects of high configuration entropy and microheterogeneity on the martensitic transforma-tion behavior and damping performance of HESMAs are clarified in this work,which provides a basis for designing alloys with superior damping properties.

关键词： High entropy s hape memory alloy Internal friction Damping Configuration entropy Martensitic transformation

Combining multiple imperfect data sources for small area estimation:a Bayesian model of provincial fertility rates in Cambodia

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Statistical Theory and Related Fields 2019年第2期3卷 178-185页

作者： Junni l.zhang John Bryant Guanghua School of Management Center for Statistical Science and Center for Data SciencePeking UniversityBeijingPeople’s Republic of China Bayesian Demography limited ChristchurchNew Zealand

Demographic estimation becomes a problem of small area estimation when detaileddisaggregation leads to small cell *** usual difficulties of small area estimation are compounded when the available data sources contain measurement *** present a Bayesianapproach to the problem of small area estimation with imperfect data *** overall modelcontains separate submodels for underlying demographic processes and for measurement *** unknown quantities in the model,including coverage ratios and demographic rates,are estimated jointly via Markov chain Monte Carlo *** approach is illustrated usingthe example of provincial fertility rates in Cambodia.

关键词： Measurement error Bayesian hierarchical model coverage errors fertility Cambodia small area estimation

Distribution of tetraether lipids in surface sediments of the northern South China Sea:Implications for TEX_(86) proxies

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Geoscience Frontiers 2013年第2期4卷 223-229页

作者： Huangmin Ge Chuanlun l.zhang Hongyue Dang Chun Zhu Guodong Jia State Key laboratory of Marine Geology Tongji University Department of Marine Sciences University of Georgia State Key laboratory of Heavy Oil Processing & Centre for Bioengineering and Biotechnology China University of Petroleum(East China) MARUM Center for Marine Environmental Sciences and Department of Geosciences University of Bremen CAS Key laboratory of Marginal Sea Geology Guangzhou Institute of GeochemistryChinese Academy of Sciences

Archaea have unique glycerol dialkyl glycerol tetraether（GDGT） lipids that can be used to develop paleotemperature proxies such as *** research is to validate proposed GDGT-proxies for paleotemperature determination in the South China Sea（SCS）.Samples were collected from core-top sediments （0-5 cm） in the northern *** lipids were extracted to obtain core GDGTs,which were identified and quantified using liquid chromatography-mass spectrometry（lC-MS）.The abundance of isoprenoidal GDGTs（/GDGTs） ranged from 271.5 ng/g dry sediment to 1266.3 ng/g dry sediment,whereas the branched GDGTs（bGDGTs）,supposedly derived from terrestrial sources,ranged from 22.2 ng/g dry sediment to 56.7 ng/g dry *** TEX_（86）-derived sea surface temperatures ranged from 20.9℃in the coast（water depth 〈 160 m） to 27.9℃offshore（water depth 〉 1000 m）.TEX86-derived temperatures near shore（〈 160 m water depth） averaged 23.1±2.5℃（n =4）,which were close to the satellite-derived winter mean sea surface temperature（average 22.6±1.0℃,n = 4）;whereas the TEX_（86）-derived temperatures offshore averaged 27.4±0.3℃（n = 7） and were consistent with the satellite mean annual sea surface temperature（average 26.8±0.4℃,n = 7）.These results suggest that TEX_（86） may record the sea surface mean annual temperature in the open ocean,while it likely records winter sea surface temperature in the shallower water.

关键词： Archaea GDGTs TEX86 Paleotemperature Northern South China Sea

RESEARCH ON THE SElECTION OF FRICTION MODElS IN THE FINITE ElEMENT SIMUlATION OF WARM EXTRUSION

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Acta Metallurgica Sinica(English letters) 2003年第2期16卷 90-96页

作者： X.B.lin H.S.Xiao Z.l.zhang National Die and Mold CAD Engineering Research Center Shanghai Jiao Tong University1954 Hua Shan RoadShanghai 200030ChinaNational Die and Mold CAD Engineering Research CenterShanghai Jiao Tong University1954 Hua Shan RoadShanghai 200030ChinaNational Die and Mold CAD Engineering Research CenterShanghai Jiao Tong University1954 Hua Shan RoadShanghai 200030China

During the process of finite element simulation of precision warm forging, the selection of friction models has a direct effect on the precision accuracy of finite element simulation results. Among all the factors which influence the selection of friction models, the distribution rule of normal stress at the tool-workpiece interface is a key one. To find out the distribution rule of normal stress at the tool-workpiece interface, this paper has made a systematic research on three typical plastic deformation processes: forward extrusion, backward extrusion, and lateral extrusion by a method of finite element simulation. Then on the base of synthesizing and correcting traditional friction models, a new general friction model which is fit for warm extrusion is developed at last.

关键词： friction model warm extrusion finite element simulation

ANAlYSIS OF STABIlITY CHARACTERISTICS OF NONlINEAR FlUID STRUCTURE INTERACTION SYSTEM IN INTERNAl FlOWS

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Journal of Hydrodynamics 2001年第2期13卷 96-105页

作者： zhang, l.X. Huang, W.H. li, J.B. Kunming Univ. of Sci. and Technol. Kunming 650051 China

A set of nonlinear partial differential equations was used to describe the motions of an internal flowing system, with the consideration of transient fluid structure interaction (FSI). The stability characteristics of the system were analyzed on the basis of the nonlinear FSI-equation model. The results show that the stability of the nonlinear FSI system become very complicated because of the influence of strongly coupled interaction between flowing liquid and vibrating pipe. The flowing velocity, pressure, the piping stiffness, and constrained conditions, etc. play a very important role in developing procedure of the system stabilization. In an analysis example given in this paper, for example, when the flowing pressure is comparatively small, the system exhibits flutter instability, and when the flowing pressure is increases to a specified value, a subcritical divergence and a supercritical flutter bifurcation take successively place in the same velocity range.

关键词： Bifurcation (mathematics) Differential equations Equations of motion Flow interactions Vibrations (mechanical)