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The General Characteristics and Distribution of the Glaucophane-Schist Belts of china

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Acta Geologica Sinica(English Edition) 1990年第1期64卷 101-114页

作者： Dong Shenbao Dong Shenbao department of Geology, peking university, beijing department of Geology Peking University Beijing

On the basis of the temperature variation, the glaucophane-schist facies Gan be classified into two faciesgroups, the glaucophane-lawsonite facies group and the glaucophane-greenschist facies group, and forms vari-ous facies series with other metamorphic facies. Glaucophane-schist belts of china are of different types withregard to their average T-P gradients and tectonic environments. They are: (1) Proterozoic intracratonicglaucophane-schist belts, (2) Caledonian intracratonic glaucophane-schist belts, (3) Palaeozoic pericratonicglaucophane-schist belts along the northern margin of the Chinese Platform, and (4) Meso-Cenozoicglaucophane-schist belts related to subduction. The initiation and evolution of glaucophane-schist metamorphism are related to their tectonic environ-ments. Most glaucophane-schist belts of china were formed in sialic environments. First the crust began tobreak up and eventually oceanic crust was formed. It seems that a non-uniformitarian mechanism may be in-volved as this evolution is related to the change of the configuration of the heat flow within the crust.

关键词： meta ab The General Characteristics and Distribution of the Glaucophane-Schist Belts of china

Population pharmacokinetics of valproate in Chinese children with epilepsy

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Acta Pharmacologica Sinica 2007年第10期28卷 1677-1684页

作者： De-chun JIANG~(2,3),Li WANG~4,Yu-qin WANG~(2,6),Lin LI~3,Wei LU~5,Xiang-rong BAI~2~2 department of Pharmacy,Xuan-wu Hospital of Capital Medical university,beijing 100053,china ~4 department of Pediatrics,peking universityFirst Hospital,beijing 100034,china ~3.department of Pharmacology,Xuan-wu Hospital of Capital Medical university,Education Ministry KeyLaboratory for Neurodegenerative Diseases,beijing 100053,china ~5 School of Pharmaceutical Science,peking university,beijing 100083,china department of Pharmacy Xuan-wu Hospital of Capital Medical University Beijing China department of Pharmacology Xuan-wu Hospital of Capital Medical University Education Ministry Key Laboratory for Neurodegenerative Diseases Beijing China department of Pediatrics Peking University First Hospital Beijing China School of Pharmaceutical Science Peking University Beijing China

Aim:The aim of the present study is to establish a population pharmacokinetic（PPK） model of valproate （VPA） in Chinese epileptic children to promote thereasonable use of anti-epileptic ***:Sparse data of VPA serumconcentrations from 417 epileptic children were *** patients weredivided into 2 groups:the PPK model group （n=317） and the PPK valid group（n=100）.The PPK parameter values of VPA were calculated by NONMEM soft-ware using the data of the PPK model group.A basic model and a final modelwere set *** validate the 2 models,the concentrations of PPK valid groupwere predicted by each model,*** mean prediction error （MPE）,mean squared prediction error （MSPE）,root mean squared prediction error（RMSPE）,weight residues （WRES）,and the 95% confidence intervals （95%CI） were also ***,the values between the 2 models were ***:The PPK of VPA was determined by a 1-compartment model with afirst-order absorption *** basic model was:Ka=3.09 (h-1),V/F=20.4（L）,CL/F=0.296 （L/h）.The final model was:Ka=0.251+2.24·（1-HS）(h-1),V/F=2.88+0.157·WT （L）,CL/F=0.1060.98·CO+0.0157·AGE （L/h）.For thebasic model,the MPE,MSPE,RMSPE,WRES,and the 95% CI were-23.53（-30.36,-16.70）,3728.96 （2872.72,4585.20）,39.62 （34.34,44.90）,and-0.06 （-0.14,0.02）,*** the final model,the MPE,MSPE,RMSPE,WRES,and the95% CI were-1.16 （-4.85,2.53）,1002.83 （1050.64,1143.61）,23.04 （21.12,24.96）,and0.08 （-0.04,0.20）,*** final model was more optimal than the ***:The PPK model of VPA in Chinese epileptic children wassuccessfully *** will be valuable to facilitate individualized dosageregimens.

关键词： population pharmacokinetics valproic acid epilepsy children Bayesian method NONMEM software individualized dosage regimens

A SMALLEST SINGULAR VALUE METHOD FOR SOLVING INVERSE EIGENVALUE PROBLEMS

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Journal of Computational Mathematics 1996年第1期14卷 23-31页

作者： S.F. Xu(department of Mathematics, peking university, beijing) 北京大学数学系北京

Utilizing the properties of the smallest singular value of a matrix, we propose a new, efficient and reliable algorithm for solving nonsymmetric matrix inverse eigenvalue problems, and compare it with a known method. ... 详细信息

关键词： Math A SMALLEST SINGULAR VALUE METHOD FOR SOLVING INVERSE EIGENVALUE PROBLEMS

Design of an MRI quadrature-data acquisition card

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Progress in Natural Science:Materials International 2006年第3期16卷 255-259页

作者： JIANG Zhongde, ZU Donglin and GU Xiaofang (Institute of Heavy Ion physics, beijing Key Laboratory of Medical physics & Engineering, School of physics, peking university,beijing 100871, china) Institute of Heavy Ion physics Beijing Key Laboratory of Medical Physics and Engineering School of Physics Peking University Beijing 100871 China

A design of a quadrature-data acquisition card based on peripheral component interconnect (PCI) bus for mini-type magnetic resonance imaging (MRI) system is reported. It uses two high speed analog-to-digital converters (ADCs) to sample the MRI signals and two static random access memories (SRAMs) to store the data which will be read to the computer by PCI bus after sampling. All the logic control signals on the card are generated by the field programmable gate array (FPGA). The software Foundation3.1 is used to design the FPGA and achieve useful result after simulating and implementing. The card has some merits that normal commercial cards do not have. For example, the sampling parameters can be varied according to different pulse sequences.

关键词： MRI data acquisition FPGA PCI bus.

Inconsistency between WMAP data and released map

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Chinese Science Bulletin 2010年第10期55卷 907-909页

作者： LIU Hao1 & LI TiPei1,2,3 1 Key Laboratory of Particle Astrophysics,Institute of High Energy physics,Chinese Academy of Sciences,beijing 100049,china 2 department of physics & Center for Astrophysics,Tsinghua university,beijing 100084,china 3.department of Engineering physics & Center for Astrophysics,Tsinghua university,beijing 100084,china Key Laboratory of Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Beijing China department of physics & Center for Astrophysics Tsinghua University Beijing China department of Engineering physics & Center for Astrophysics Tsinghua University Beijing China

A remarkable inconsistency between the calibrated differential time-ordered data (TOD) of the Wilkinson Microwave Anisotropy Probe (WMAP) mission,which is the input for map-making,and the cosmic microwave background (CMB) temperature maps published by the WMAP team is revealed,indicating that there must exist a serious problem in the map making routine of the WMAP *** inconsistency is easy to be confirmed without the use of WMAP map-making *** view of the importance of this issue for cosmology study,we invite readers to check it by themselves.

关键词：威尔金森微波各向异性探测器 WMAP 地图制作宇宙微波背景有序数据制作软件 TOD CMB

THE APPLICATION OF DISCRETE ELEMENT METHOD IN SOLVING THREE-DIMENTIONAL IMPACT DYNAMICS PROBLEMS

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Acta Mechanica Solida Sinica 2003年第3期16卷 256-261页

作者： Liu Kaixin Gao Lingtian (department of Mechanics and Engineering Science,peking university,beijing 100871,china) department of Mechanics Science Peking University Beijing 100871 China

A three-dimensional discrete element model of the connective type is presented. Moreover,a three-dimensional numerical analysis code,which can carry out the transitional pro- cess from connective model(for continuum)to contact model(for non-continuum),is developed for simulating the mechanical process from continuum to *** wave propagation process in a concrete block(as continuum)made of cement grout under impact loading is numer- ically simulated with this *** comparing its numerical results with those by LS-DYNA,the calculation accuracy of the model and algorithm is ***,the failure process of the concrete block under quasi-static loading is demonstrated,showing the basic dynamic tran- sitional process from continuum to *** results of calculation can be displayed by *** damage modes are similar to the experimental *** two numerical examples above prove that our model and its code are powerful and efficient in simulating the dynamic failure problems accompanying the transition from continuum to *** also shows that the discrete element method(DEM)will have broad prospects for development and application.

关键词： discrete element method three-dimensional model impact stress wave dynamic failure

Recursive equations for compound distribution with the severity distribution of the mixed type

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Science china Mathematics 2005年第5期48卷 594-609页

作者： YANG Jingping, CHENG Shihong & WU Qin LMAM, department of Financial Mathematics, peking university, beijing 100871, china LMAM Department of Financial Mathematics Peking University Beijing China

In this paper, recursive equations are obtained for compound distribution with the number of claims belonging to (a, b)-family and the severity distribution of the mixed type. Numerical methods to solve these equation... 详细信息

关键词： recursive equation compound distribution (a b)-family severity distribution of the mixed type.

Discrepancy of the magnetic behaviors and crystalline structure on the Co/FeMn and FeMn/Co interfaces with ultrathin Pt spacer

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Rare Metals 2010年第5期29卷 473-479页

作者： LIU Yang,FU Yanqiang,JIN Chuan,and FENG Chun department of Materials physics and Chemistry,university of Science and Technology beijing,beijing 100083,china department of Materials physics and Chemistry University of Science and Technology Beijing Beijing China

The exchange coupling at the ferromagnetic/antiferromagnetic （FM/AFM） interface is influenced by both the magnetic structure and the crystalline micro-structure. Co/FeMn/Co thin films with 0.4 nm Pt spacer layer inserted into the Co/FeMn and FeMn/Co interface respectively were deposited by means of magnetron sputtering. The two interfaces upon and beneath the FeMn layer show distinct behaviors before and after the Pt spacer inserted. There is a remarkable shrink of the interracial uncompensated spins within the FeMn bottom interracial monolayers, whereas a relaxation of the pinning strength of the FeMn interfacial spins along the out-of-plane direction occurs at the top in- terface. XRD analysis indicates the Pt layer upon the FeMn layer forms an fcc （002） texture, implying the magnetic discrepancy between the top and bottom FeMn interfaces has crystalline structural origins.

关键词： interfaces exchange coupling exchange bias spacer stress anisotropy lattice match

EFFECT OF Cr ADDITION ON MICROSTRVCTURES AND MECHANICAL PROPERLIES OF β-NiAl ALLOYS

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Acta Metallurgica Sinica(English Letters) 1999年第2期12卷 173-180页

作者： W.H. Tian S.L. Hu and M. Nemoto(1) department of Materials physics, university of Science and Technology beijing, beijing 100083, china 2) department of Materials Forming, university of Science and Technology beijing, beijing 100083, china 3) department Univ of Science and Technology Beijing Beijing China

The effect of Cr addition on the microstructures and mechanical properties of NiAl inermetallic alloys containing 4 to 8 mol% Cr has been characterized. It is shown that Cr is not only an efficient soild solution strengthener in NiAl, it is also an efficient precipitation Strengthener by fine dispersion of α-Cr particles. Transmission electron microscope observations have revealed that fine spherical particles of α-Cr appeared homogeneously in the NiAl matrix by aging at temperatures around 1073K after solution annealing at 1563K. The aging behavior was investigated by microhardness measurements and the temperature dependence of the yield stress of NiAl containing α-Cr particles was investigated by compression tests over the tempemture range from 298 to 1173K. NiAl alloys happened appreciably by the precipitation of α-Cr *** bypass the particles during deformation and typical Orowan loops were observed surrounding the α-Cr particles after deformation. Although the dispersion Of α-Cr particles increases the yield strength of NiAl at intermediate temperutre, the strength decreases appreciably at higher temperatures.

关键词： NiAl age-hardening precipitate deformation mechanism microstructure