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Calculating Models of Mass Action Concentrations for Fe-P and Cr-P Melts and Optimization of Their Thermodynamic Parameters

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International Journal of Minerals,Metallurgy and Materials 1999年第3期13卷 174-177页

作者： Jian Zhang(Metallurgy school, university of Science and Technology beijing, beijing 100083, china) Metallurgy school University of Science and Technology Beijing Beijing 100083 China

Based on the phase diagrams, reliable reference experimental data and the coexistence theory of metallic melts structure involving compound formation, calculating models of mass action concentrations for Fe-P and Cr-P melts have been formulated. At the same time, some of their thermodynamic parameters have been optimized. The calculated results not only agree well with the measuredvalues, but also obey the mass action law rigorously, this in turn shows that these models can reflect the structural characteristics of corresponding melts.

关键词： activity phase diagram coexistence theory mass action concentration

Influence of magnetic current on the ground state entanglement in an isotropic transverse XY chain

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Progress in Natural Science:Materials International 2007年第10期17卷 1147-1151页

作者： Liu Dan1,2 , Zhang Yong3 and Long Guilu1,2(1. Key Laboratory for Atomic and Molecular NanoSciences, and Department of Physics, tsinghua university, beijing 100084, china 2. Center of Quantum Information Science and Technology, tsinghua National Laboratory for information Science and Technology, beijing 100084, china 3. Institute of Physics, school of Sciences, beijing university of Posts and Telecommunications, beijing 100876, china) Key Laboratory for Atomic and Molecular NanoSciences Department of Physics Tsinghua University Beijing 100084 China Center of Quantum Information Science and Technology Tsinghua National Laboratory for Information Science and Technology Beijing 100084 China Institute of Physics School of Sciences Beijing University of Posts and Telecommunications Beijing 100876 China

We study the ground state entanglement in a three-qubit XY chain under the influence of a magnetization current. It is found that the ground state changes from a W state to a disentangled state as the magnetic field varies. When the Lagrange multiplier λ>3, namely under a strong magnetic current, the ground state holds onto a W state for a large range of the magnetic field strength. A phase transition to the magnetization-current phase occurs under a certain condition.

关键词： Heisenberg-XY chain magnetic-current phase transition.

A Back Look on the Binary Phase Diagrams of Metals from the Mass Action Law and the Coexistence Theory of Metallic Melts

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Journal of university of Science and Technology beijing 2001年第1期8卷 15-19页

作者： Jian Zhang Metallurgy school, university of Science and Technology beijing, beijing 100083, china Metallurgy school Univ. of Science/Technology Beijing Beijing 100083 China

According to the mass action law and the coexistence theory of metallic melts, the mass action concentrations of Cu-Mg, Bi-Tl and Ni-Al melts involving compound formation have been calculated. The calculated results show that, except the ultimate case of pure element, when two elements are present in the melts, all structural units (atoms and molecules) without exception will be present in the melts, i.e., their concentrations may change from great to small, but they will not vanish into nothing, and only under such conditions, the calculated results both agree with practice and obey the law of mass action. In view of that over considerable wide composition range, the activities of both elements of the three solid binary alloys mentioned above have been measured, this seems in contradiction with the present relevant phase diagrams, in which the structural units are determined by composition range, so the latter needs further investigation and consideration.

关键词： activity phase diagram the mass action law the coexistence theory

Geological Controls on Seismic indicators of Volcanic Gas Reservoirs:A Case Study from the Changling Fault Depression of Songliao Basin,china

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地学前缘 2009年第S1期16卷 148-149页

作者： Lun Li,Xin Zhang school of software,china university of Geosciences(beijing),beijing 100083,china.

The Songliao basin in northeast china is a Mesozoic rift basin characterized by Mesozoic and Cenozoic hydrocarbon *** Changling fault depression located in the south of the Songliao Basin,

关键词： volcanic gas reservoirs central eruption crevice eruption Changling depression

Effects of disinhibition on spatiotemporal pattern of neuronal first recruitment in neuronal networks

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Progress in Natural Science:Materials International 2009年第5期19卷 615-621页

作者： Liangbin Pana,b,c,1, Xindong Songa,b,c,1, Guangxin Xiang a,b,c, Jing Zhua,b,c, Jing Cheng a,b,c,d,a Medical Systems Biology Research Center, tsinghua university school of Medicine, beijing 100084, china b Department of Biological Sciences and Biotechnology, tsinghua university, beijing 100084, china c National Engineering Research Center for beijing Biochip Technology, 18 Life Science Parkway, beijing 102206, china d State Key Laboratory of Biomembrane and Membrane Biotechnology, tsinghua university, beijing 100084, china Medical Systems Biology Research Center Tsinghua University School of Medicine Beijing 100084 China Department of Biological Sciences and Biotechnology Tsinghua University Beijing 100084 China National Engineering Research Center for beijing Biochip Technology 18 Life Science Parkway Beijing 102206 China State Key Laboratory of Biomembrane and Membrane Biotechnology Tsinghua University Beijing 100084 China

The propagation of neuronal activities is a key feature to understanding information processing in networks. The analysis based on first-spikes of bursts in turn plays an important role in the research of neuronal activity propagation. Our focus here is to investigate how spatiotemporal patterns of neuronal first-spikes are affected by disinhibition. Multi-electrode arrays were used to record stimulation-evoked bursts of multiple neurons in randomly cultured neuronal networks. Both the precise timing of and the rank relationships between first-spikes were analyzed. Compared with evoked bursts in the network’s native state, the precise first-spike latencies in its dis-inhibited state are more consistent and the propagation of its bursting activities is much faster. Additional points of interest are that disinhibited neuronal networks can be evoked to generate stable and distinguishable neuronal first recruitment spatiotemporal patterns specific to the stimulation site, and that the disinhibition may cause the original spatiotemporal patterns to change in a heterogeneous manner with regards to different propagation pathways.

关键词： Neuronal recruitment Spatiotemporal pattern Disinhibition Network Multi-electrode array

Research on Electric Impedance Spectroscopy of Living Cell Suspensions by a Chip with Microelectrodes

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稀有金属材料与工程 2006年第S3期 429-432页

作者： Xing Yang~(1,2,3) Zhaoying Zhou~(1,2,3) Mingfei Xiao~(1,2,3) Ying Wu~(1,2,3) Shangfeng Liu~4 (1.MEMS Lab.,Department of Precision Instruments & Mechanology,tsinghua university,beijing 100084,china) (2.Micro-Nano Technology Research Center,tsinghua university,beijing 100084,china) (3.State Key Laboratory of Precision Measurement Technology and Instruments,tsinghua university,beijing 100084,china) (4.school of Medicine,tsinghua university,beijing 100084,china)

A microfabricated electrical impedance spectroscopy (EIS) chip with microelectrodes was *** substrate and the electrodes of the chip were made of glass and gold,*** experimental results demonstrated that the EIS-chip could distinguish different solutions (physiological saline,culture medium,living cell suspension etc.) by scanning from 10Hz to 45kHz.A 6-element circuit model was used for fitting the real part and the imaginary part admittance curves of the living cell *** actual circuit was also built and tested to verify the 6-element circuit model *** micro-EIS chip has several advantages including the use of small sample volumes,high resolution and ease of *** shows good application prospects in the areas of cellular electrophysioiogy,drug screening and bio-sensors etc.

关键词： electrical impedance spectroscopy(EIS) microelectrode living cell suspension 6-element

Method for tumor recognition with short dynamic PET images:Theory and simulation study

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Progress in Natural Science:Materials International 2009年第1期19卷 73-77页

作者： Huiting Qiao a,Jing Bai a,Yingmao Chen b,Jiahe Tianb a Department of Biomedical Engineering,school of Medicine,tsinghua university,beijing 100084,china b Department of Nuclear Medicine,General Hospital of PLA,beijing 100853,china Department of Biomedical Engineering School of Medicine Tsinghua University Beijing 100084 China Department of Nuclear Medicine General Hospital of PLA Beijing 100853 China

A new method was provided in this paper to recognize tumor in PET images automatically and reduce the waiting time of *** on the unsupervised clustering algorithm(ISODATA),this method diagnoses tumor with short dynamic PET *** theoretical basis of this method is that the metabolic characteristics of different tissues,represented by time-activity curve in the region of interest,are *** computer program was developed and validated using simulated dynamic PET data with small tumor in *** study shows that this method could recognize tumor with the short dynamic PET data in 10 min successfully,and this method was not sensitive to initial cluster center.

关键词： Dynamic PET Clustering algorithm Tumor recognition Simulation

A quantification model for apoptosis in mouse embryos in the early stage of fetation

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Science china(Life Sciences) 2009年第10期52卷 922-927页

作者： WANG PengFei1, FU JianHua1, MA WanYun1, CHEN DieYan1, Lü DanYu2 & BAI WenJia3 1 Key Laboratory for Atomic and Molecular Nanosciences of Education Ministry, Department of Physics, tsinghua university, beijing 100084, china 2 Department of Anatomy & Histology and Embryology, school of Basic Medical Sciences Peking university Health Science Center, beijing 100083, china 3 Department of Automation, tsinghua university, beijing 100084, china Key Laboratory for Atomic and Molecular Nanosciences of Education Ministry Department of Physics Tsinghua University Beijing China Department of Anatomy & Histology and Embryology School of Basic Medical Sciences Peking University Health Science Center Beijing China Department of Automation Tsinghua University Beijing China

Apoptosis is the most important inducement and modulator for embryos in the early stage of fetation, i.e. after the 8-cell stage, mostly the morula and blastula stage, to proceed to the stage of nonlinear development. Using a two-photon laser scanning microscopy (TPLSM) system, we obtained 3-dimensional (3D) fluorescent images of preimplantation mouse embryos. A model for quantification was established. The statistical results for the spatial location of apoptosis bodies in embryos was obtained following image processing, as well as investigation of the kinetics of apoptosis. It was found that most (70%) apoptosis occurred in the trophectoderm, and the departure between the centroid and geometric center of embryos had a step transition when embryos developed into the 32-cell stage, which was consistent with the theoretical prediction that the blastocele would induce a symmetry break of the distribution of cells in embryos.

关键词： apoptosis preimplantation mouse embryo TPLSM quantification model

INFINITE ELEMENT METHOD FOR THE EXTERIOR PROBLEMS OF THE HELMHOLTZ EQUATIONS

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Journal of Computational Mathematics 2000年第6期18卷 657-672页

作者： Lung-an Ying (school of Mathematical Sciences, Peking university, beijing 100871, china) 北京大学北京 100871

There are two cases of the exterior problems of the Helmholtz equation. If λ ≥ 0 the bilinear form is coercive, and if λ < 0 it is the scattering problem. We give a new approach of the infinite element method, which enables us to solve these exterior problems as well as corner problems. A numerical example of the scattering problem is given. [ABSTRACT FROM AUTHOR]

关键词： Helmholtz equation exterior problem infinite element method