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Journal of university of Science and Technology beijing 2002年第3期9卷 170-176页

作者： Man ZhangMetallurgy School, university of Science and Technology beijing, beijing 100083. china (Received 2001-10-27) Metall. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Based on the phase diagrams, measured activities and the annexationprinciple, calculating models of mass action concentrations for In-Bi-Cu and In-Sb-Cu melts havebeen formulated. Calculated results not only agree well with practical values, but also obey themass action law, showing that the deduced model can reflect the structural reality of given meltasand that the annexation principles is applicable to these tow ternary metallic melts. So long asthere is one from three binary systems constituting the ternary melts, in which the activities ofone component exhibit positive deviation relative to Raoultian behavior, heterogeous meltsinevitably would form, so heterogeneous calculating model should be used to calculate their massaction concentrations. On the contrary, if all the binary melts are homogeneous and their activitiesexhibit negative deviation with respect to the Raoult's law, then the ternary melts formed fromthem will certainly be homogeneous, hence single phase model should be applied.

关键词： activity mass action concentration coexistence theory annexationprinciple

Riemann problem for one-dimensional binary gas enhanced coalbed methane process

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Theoretical & Applied Mechanics Letters 2011年第6期1卷 41-44页

作者： Changfu Tang,) and Xiaodong Wang School of Energy Resources, china university of geosciences ({3.), beijing 100083. china School of Energy Resources China University of Geosciences (Beijing) Beijing 100083 China

With an extended Langmuir isotherm, a Riemann problem for one-dimensional binary gas enhanced coalbed methane (ECBM) process is investigated. A new analytical solution to the Riemann problem, based on the method of characteristics, is developed by introducing a gas selectivity ratio representing the gas relative sorption affinity. The influence of gas selectivity ratio on the enhanced coalbed methane processes is identified.

关键词： Riemann problem binary gas enhanced coalbed methane method of characteristics gas selectivity ratio

Assessment of the apparent activation energies for gas/solid reactions—carbonate decomposition

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Journal of university of Science and Technology beijing 2003年第2期10卷 25-29页

作者： Jianhua Liu and Jiayun ZhangMetallurgical Engineering School, university of Science and Technology beijing, beijing 100083. china Metall. Eng. Sch. Univ. of Sci. and Technol. Beijing Beijing 100083 China

The guidelines for assessing the apparent activation energies of gas/solidreactions have been proposed based on the experimental results from literatures. In CO_2 free inletgas flow, CaCO_3.decomposition between 950 and 1250 K with thin sample layer could be controlled bythe interfacial chemical reaction with apparent activation energy E = (215+-10) KJ/mol and E=(200+-10) kJ/mol at T = 813.to 1020 K, respectively. With relatively thick sample layer between 793.nd 1273.K, the CaCO_3.decomposition could be controlled by one or more steps involvingself-cooling, nucleation, intrinsic diffusion and heat transfer of gases, and E could vary between147 and 190 kJ/mol. In CO_2 containing inlet gas flow (5 percent-100 percent of CO_2), E wasdetermined to be varied from 949 to 2897 kJ/mol. For SrCO_3.and BaCO_3.decompositions controlled bythe interfacial chemical reaction, E was (213.-15) kJ/mol (1000-13.0K) and (3.5+-15) kJ/mol(1260-1400 K), respectively

关键词： assessment activation energy decomposition carbonate

Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1, CUI Xi-min2, YU Yi-ju3.1. School of Surveying and Landing Information Engineering, Henan Polytechnic university, Jiaozuo 454003. china 2. College of Geoscience and Surveying Engineering, china university of Mining and Technology, beijing 100083. china 3. Surveying and Mapping Press, beijing 100045, china School of Surveying and Landing Information Engineering Henan Polytechnic University Jiaozuo 454003 China College of Geoscience and Surveying Engineering China University of Mining and Technology Beijing 100083 China Surveying and Mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.13. mm and vertical direction is ±0.192 mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor

EFFECT OF NITROGEN ON GRAPHITE MORPHOLOGY IN GRAY CAST IRON

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Acta Metallurgica Sinica(English Letters) 1993年第8期6卷 151-155页

作者： ZHAI Qijie HU Hanqi university of Science and Technology beijing,beijing,{3. Faculty of Foundry,university of Science and Technology beijing,beijing 100083.{3. beijing Univ of Science and Technology Beijing China

The distribution of N and morphology of graphite in gray cast iron containing N were studicd by adopting the man-made specimens of Fe-C-Si-Mn alloys with some N added. The N adsorbed along the interfaces between graphite and matrix together with solid- solutioned in graphite is believed to be the principal cause of morpholongical variation of graphite.

关键词： gray cast iron graphite morphology N

Some basic concepts and problems on the petrogenesis of intra-plate ocean island basalts

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Chinese Science Bulletin 2009年第22期54卷 4148-4160页

作者： NIU Yaoling1,2,3.1 Department of Earth Sciences, Durham university, Durham DH1 3.E, UK 2 School of Earth Sciences and Resources, china university of {3., beijing 100083. china 3.School of Earth and Space Sciences, Peking university, beijing 100871, china Department of Earth Sciences Durham University Durham UK School of Earth Sciences and Resources China University of Geosciences Beijing China School of Earth and Space Sciences Peking University Beijing China

Basaltic magmatism that builds intra-plate ocean islands is often considered to be genetically associated with "hotspots" or "mantle plumes". While there have been many discussions on why ocean island basalts (OIB) are geochemically highly enriched as an integral part of the mantle plume hypothesis, our current understanding on the origin of OIB source material remains unsatisfactory, and some prevailing ideas need revision. One of the most popular views states that OIB source material is recycled oceanic crust (ROC). Among many problems with the ROC model, the ocean crust is simply too depleted (e.g., [La/Sm]PM > 1) OIB. Another popular view states that the enriched component of OIB comes from recycled continental crust (RCC, i.e.; terrigenous sediments). While both CC and OIB are enriched in many incompatible elements (e.g., both have [La/Sm]PM >>1), the CC has characteristic enrichment in Pb and deletion in Nb, Ta, P and Ti. Such signature is too strong to be eliminated such that CC is unsuitable as source material for OIB. Plate tectonics and mantle circulation permit the presence of ROC and RCC materials in mantle source regions of basalts, but they must be volumetrically insignificant in contributing to basalt magmatism. The observation that OIB are not only enriched in incompatible elements, but also enriched in the progressively more incompatible elements indicates that the enriched component of OIB is of magmatic origin and most likely associated with low-degree melt metasomatism. H2O and CO2 rich incipient melt may form in the seismic low velocity zone (LVZ). This melt will rise because of buoyancy and concentrate into a melt rich layer atop the LVZ to metasomatize the growing lithosphere, forming the metasomatic vein lithologies. Erupted OIB melts may have three components: (1) fertile OIB source material from depth that is dominant, (2) the melt layer, and (3. assimilation of the metasomatic

关键词：岩石成因论海洋 OIB 矿物学

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 beijing, beijing 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

Vertex solution theorem for the upper and lower bounds on the dynamic response of structures with uncertain-but-bounded parameters

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Acta Mechanica Sinica 2009年第3期25卷 367-379页

作者： Zhiping Qiu Xiaojun Wang Institute of Solid Mechanics, Beihang university, 100083.beijing, {3. Institute of Solid Mechanics Beihang University Beijing China

The aim of this paper is to evaluate the effects of uncertain-but-bounded parameters on the dynamic response of structures. By combining the interval mathematics and the finite element analysis, the mass matrix, damping matrix, stiffness matrix and the external loads are represented as interval matrices and vector. With the help of the optimization theory, we present the vertex solution theorem for determining both the exact upper bounds or maximum values and the exact lower bounds or minimum values of the dynamic response of structures, in which these parameters reach their extreme values on the boundary of the interval mass, damping, stiffness matrices and the interval extemal loads vector. Three examples are used to illustrate the computational aspects of the presented vertex solution theorem.

关键词： Dynamic response Vertex solution theorem ,Uncertain-but-bounded parameters

BIFURCATION SOLUTIONS TO A BOUNDARY LAYER PROBLEM ARISING IN THE THEORY OFPOWER LAW FLUIDS

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Acta Mathematica Scientia 2000年第1期20卷 19-26页

作者：郑连存马连喜赫冀成 Institute of Fluid Mechanics Beijing University of Aeronautics and Astronautics Beijing 100083 China School of Matherials Sciences and Technology China University of Geosciences Beijing 100083 China Thermal Engineering Department Northeastern University Shenyang 110006 China

The present paper deals with a singular nonlinear boundary value problem arising in the theory of power law fluids, sufficient conditions for the existence of bifurcation solutions to the problem are obtained.

关键词： bifurcation solution boundary layer problem pseudo-plastic fluids

Numerical Simulation on Irregular Shrinkage of Initial Shell in Continuous Casting of Steel

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International Journal of Minerals,Metallurgy and Materials 1999年第2期13卷 103-106页

作者： Dejun Jing Kaike Cai(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 microstructures of steel, a thermo-elasto-plastic stress model of continuously casting billets is established to study hailal solidifying process in molds. Results show that peritectic phase transformation contributes greatly to the irregular shrinkage ofinitial shell, which makes the billets vulnerable to surface defects.

关键词： thermo-elasto-plastic stress model peritectic phase transformation irregular shrinkage of initial shell