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Rare Metals 2002年第2期21卷 142-151页

作者： ZHANG JianMetallurgical engineering school.university of science and Technology {3., {3. 100083. China Metallurgical engineering School University of Science and Technology Beijing 北京 100083

Based on the phase diagrams, measured activities an the annexationprinciple, the calculating models of mass action concentrations forin-Pb-Ag and In-Bi-Sb ternary metallic melts have been *** results of calculation both agree with practice, and obey the lawof mass action, showing that the models formulated can reflect thestructural reality of the corresponding melts and the annexationprinciple is applicable to the them.

关键词： activity mass action concnetration th annexation principle In-PB-Ag

A New Safety Electric Initiating System

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International Journal of Minerals,Metallurgy and Materials 1999年第4期13卷 306-308页

作者： Daze Lin(Resource engineering School, university of science and Technology {3., {3. 100083. China) Univ of science and Technology Beijing Beijing China

Based on the analysis of weakness on the safety of traditional electric detonators, a BJ-l safety electric detonator initiatingsystem and its corresponding safe examination technique were successfully developed. By leading false foot wires and taking advantageof the transmitting frequency band of Mo-Zn ferrite, detonators in this new system can completely impede the direct induction of outsidecrosstalk that may cause casual firing in the ordinary as well as eleclromagnetic ones. Possible causality by lightning was discussed. Results are presented, of its safety tests on resistance to direct and alternating current, electrostatic, and crosstalk induced by damp leakagein saturated salty water.

关键词： electric detonator blasting engineering, electric initiating system, safety

Patterns of platinum-group elements in mantle peridotite, granulite xenoliths and basalt in Hannuoba

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Chinese science Bulletin 1999年第18期44卷 1676-1681页

作者： CHU Xuelei, LI Xiaolin, XU Jiuhua and LIU Jianming1. The Research Center of Mineral Resources Exploration , Chinese Academy of sciences , beijing 100101, China 2. Institute of Geology , Chinese Academy of sciences , beijing 100029, China 3. Institute of High Energy Physics , Chinese Academy of sciences , beijing 100817 , China 4. beijing university of science and engineering , beijing 100083. China corresponding author The Research Center of Mineral Resources Exploration Chinese Academy of Sciences Beijing China Institute of Geology Chinese Academy of Sciences Beijing China Institute of High Energy Physics Chinese Academy of Sciences Beijing China beijing university of science and {3. Beijing China

Neutron activation analysis after preconcentration of nickel sulfide fire assay was used in measurement of Ru, Ph, Pd, Os, Ir, Pt (i.e. PGE elements) and Au concentrations for basalt, mantle and granulite xenoliths in Hannuoba. The chondrite- and primitive mantle-normalized PGE patterns generally exhibit flat (for Iherzolite), negative slope (for harzburgite),

关键词： mantle xenolith granulite xenolith basalt platinum-group element Hannuoba.

Sol-gel Preparation and Infrared Radiation Property of Boron-substituted Cordierite Glass-ceramics

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Journal of Materials science & Technology 2010年第5期26卷 445-448页

作者： Shuming Wang and Fenghua Kuang School of Materials science and engineering,university of science & Technology {4.,{4. 100083.China [a] School of Materials science and engineering university of science & Technology beijing beijing 100083 China

Boron for aluminum substitution in the cordierite structure has been examined by sol-gel preparation of different samples along the compositional junction Mg2Al4.xBxSi5O18 with x=0,0.5,1,*** increasing the x value from 0 to 1.5 the crystallization behavior changed *** amount B2O3.doping can promote the sintering of amorphous cordierite gel,effectively restrain the precipitation of μ-cordierite and enhance the crystallization of α-*** substitution of B3. for Al3. in cordierite crystal structure can effectively improve the near-infrared spectral emissivity of this cordierite based glass-ceramics.

关键词： Sol-gel Glass-ceramics Infrared radiation B3. substitution Solid solution

Theorems for Testing Local Activity of CNN and Application to Cardiac Purkinje Equations

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International Journal of Minerals,Metallurgy and Materials 2000年第2期14卷 139-146页

作者： Lequan Min(Applied science School, university of science and Technology {3., {3. 100083. China) Applied science School University of Science and Technology Beijing Beijing 100083 China

The theorems for testing the local in one-port cellular neural/inear network (CNN) cells with four local state variables are presented. Using the theorems computes the bifurcation diagrams of the cardiac Purkinje fiber (CPE) equations Which describethe long-lasting action and pace-maker potentials of the Purkinje fiber of the heart. The computer simulation shows that periodic trajectories or convergent trajectories of the CPF Equations can be foun if the cormsponing cell Parameters are located in a positive domainbut nearby edge of chaos. In particular a heart with approximate normal frequency of heartbeat but non-normal electrocardiogram maysuddenly stop by slightly perturbing the parameters of the corresponding CPF Equations when the Paramders are located nearby the edge of chaos in the bifurcation diagrams. This research seems to interpret reasonbly the phenomena that patients with cardiac diseases might suddenly die without warning.

关键词： cellular neural network local activity cardiac Purkinje fiber heartbeat

APPLICATION OF THE ANNEXATION PRINCIPLE TO THE STUDY OF THERMODYNAMIC PROPERTIES OF TERNARY METALLIC MELTS Cd-Pb-Sb

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Acta Metallurgica Sinica(English Letters) 2001年第5期14卷 368-374页

作者： J.Zhang Metallurgical engineering School, university of science and Technology {3., {3. 100083. China Sch. of Metall. Eng. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Based on the phase diagrams, measured activities and the annexation principle, the calculating models of mass action concentrations for Cd-Pb, Pb-Sb and Cd-Sb binary as well as Cd-Pb-Sb ternary metallic melts have been formulated. The results of calculation both agree with practice and obey the mass action law. This in turn testifies that the models formulated can reflect the structural reality of corresponding melts and the annexation principle is applicable to these melts.

关键词： Antimony alloys Cadmium alloys Lead alloys Phase diagrams Thermodynamic properties

Progress and review of the studies on the end-Triassic mass extinction event

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science China Earth sciences 2005年第12期48卷 2049-2060页

作者： DENG Shenghui1,2, LU Yuanzheng1,2,3.& XU Daoyi4.1. Research Institute of Petroleum Exploration and Development, beijing 100083. China 2. Key Laboratory of Oil and Gas Reservoir of PetroChina, beijing 100083. China 3. China {4. of Geosciences, beijing 100083. China 4. Institute of Geology, China Earthquake Administration, beijing 100029, China 1. Research Institute of Petroleum Exploration and Development 100083 Beijing China 2. Key Laboratory of Oil and Gas Reservoir of PetroChina 100083 Beijing China 3. China university of Geosciences 100083 Beijing China 4. Institute of Geology China Earthquake Administration 100029 Beijing China

The mass extinction at the end-Triassic is one of the five biggest in the Phanerozoic. However,it is the least well understood among these five events, and only till last decade it became a great academic interesting subject to geologists. The evidences for this event come obviously from bivalves, brachiopods, ammonites, corals, radiolaria, ostracods and foraminifera of marine habitats, and plants and tetrapods of terrestrial realm. By contrast, for some of other groups, such as marine gastropods and marine vertebrates, no mass extinction has been recog-nized yet. The extinction event is strongly marked at specific level but shown a complicated situa-tion at generic and family levels. Dramatic changing of the environment, such as the temperature raise due to the greenhouse effect, the marine anoxic habitats caused by a sudden transgression after the regression at the end of Triassic, has been claimed to be the main cause of the extinction. Many hypotheses have been suggested to demonstrate the mechanisms of the environment changing, among which two popular ones are the bolide impact and volcanic eruption. The Triassic-Jurassic (Tr-J) boundary mass extinction event is still poorly understood because no enough data have been obtained from the Tr-J boundary successional sections of both marine and terrestrial sediments, and most of these studies were regionally restricted. The basic aspects of the event and its associated environmental conditions remain poorly characterized and the causal mechanism or mechanisms are equivocal. Some authors even doubt its occurrence. China has many successionally developed terrestrial and marine Tr-J sections. Detailed studies of these sections may be important and significant for well understanding of the event.

关键词： progress, review, end-Triassic, mass extinction, mechanism, Tr-J boundary.

Dissolving of Nb and Ti carbonitride precipitates in microalloyed steels

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Journal of university of science and Technology beijing 2003年第5期10卷 78-80页

作者： Wenjin Nie, Shanwu Yang, Shaoqiang Yuan, and Xinlai HeMaterials science and engineering School, university of science and Technology {4., {4. 100083. China Materials science and engineering School University of Science and Technology Beijing Beijing 100083 China

The dissolving behaviour of Nb and Ti carbonitride precipitates inmicroalloyed steels during isothermal holding at 13.0℃ was investigated by Transmission electronmicroscopy (TEM) and energy dispersion x-ray spectrum (EDX). It was found that all precipitates inNb-Ti microalloyed steel are (Nb, Ti)(C, N). With holding time increasing, the atomic ratio of Nb/Tiin precipitates decrease gradually. These precipitates still existe even after holding for 4. h at13.0℃ while Nb(C, N) precipitates dissolve away in Nb microalloyed steel only after 4.h at the sametemperature. These results show that formation and thermostability of precipitates are considerablyinfluenced by interaction between Nb and Ti.

关键词： dissolving (Nb, Ti)(C, N) TEM EDX

High Resolution Electron Microscopy Observations of Structural Changes in Iron Nitride Films Annealed in Vacuum

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Journal of Materials science & Technology 1997年第2期13卷 123-126页

作者： Shengkai GONG Huibin XU (Dept. of Materials science and engineering, beijing {3. of Aeronautics and Astronautics, beijing 100083. China) Dept. of Materials science and engineering Beijing University of Aeronautics and Astronautics Beijing 100083 China

Iron-nitride films were prepared by reactive sputtering, and the effect of annealing treatment on the structures was investigated by means of in-situ electron microscopy and high resolution electron microscopy (HREM). As-deposited films were observed to be a mixed structure of a few ultrafine epsilon-Fe2-3. particles existing in the amorphous matrix. it was found that the structure-relaxation in the amorphous occurred at 4.3.K, and the ultrafine grains began to grow at the higher annealing temperatures. The transition of the amorphous to epsilon-Fe2-3. was almost completed at 673.K. It is considered that the formation of the ideal epsilon-Fe3. is originated from the ordering of the nitrogen atoms during the annealing in vacuum. On the other hand, gamma'-phase (Fe4.) was seen to precipitation of epsilon-phase at 723.K. Two possible modes are proposed in the precipitation of gamma'-phase, depending on the heating rate and crystallographic orientation relationships, i.e. [121](epsilon)//[001](gamma), (2(1) over bar0$)(epsilon)//(110)(gamma) and [100](epsilon)//[110](gamma), (001)(epsilon)//(111)(gamma). In addition, alpha-Fe particles were observed to form from the gamma'-phase at high temperatures. We assumed that these structural changes are due to the diffusion of nitrogen and iron atoms during the annealing, except for the case of the precipitation of the gamma'-phase as depicted above. The results obtained in this work are in a good agreement with the assumption.

关键词： Figure High Resolution Electron Microscopy Observations of Structural Changes in Iron Nitride Films Annealed in Vacuum

Algorithm for Computation of Unstructured Real Stability Radius and Its Applications

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International Journal of Minerals,Metallurgy and Materials 1998年第4期12卷 245-250页

作者： Xiaodan Zhang Lequan Min(Applied science School, university of science and Technology {3., {3. 100083. China) Applied science School University of Science and Technology Beijing Beijing 100083 China

An algorithm for the computation of the unstructured real stability radius of high dimensional linearsystem is presented. Using the accurate formula of the real stability radius of 2-dimensional system linear systemchecks the algorithm. The result shows that the algorithm is reliable and efficient. As applications, the unstructuredreal stability radii of 2-dimensional Chua's circuit and 3.dimensional piecewise-linear system are calculated, thedynamical orbits of the corresponding perturbed systems are simulated.

关键词： lincar systems stability robustness parameter perturbation computational methods