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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

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

The evolution model of the earth's limited expanding

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Chinese Science Bulletin 2000年第4期45卷 304-313页

作者： CHEN Zhigengchina university of Mining and Technology, beijing 100083. china china university of Mining and Technology Beijing China

Based on the prerequisite that the earliest acid rock formed because of the initial global expanding tectonic processes, by combining it with other geological limitation conditions, and starting from the lithosphere elastic mechanics, the following is defined : the earth expansion started at about 43.0 Ma ago, the average increasing rate of the earth radius is 0.40 mm/a, the initial expanding earth radius is 4651 km, and the initial global expansion of tectonic processes happened at 4183.7 Ma ago. From the natural and attenuation evolution condition of the earth and terrestrial planets, through the limit condition got from the combination of the mathematics logic and the geological significance, the limited expanding earth evolution model is established as follows:in which R0= 4.651×106 m, A =1.86×106 m, β = -6.01?10-10 a and ts=3.10 a. From this model the maximum radius Rmax of the limited expanding earth evolution should be 6511 km. The earth’s radius increasing rate is about 0.1 mm/a at present.

关键词： limited earth expansion evolution model start time of expansion start time of expanding tectonism stage character of tectonism .

Study on the Removal of Iron,Manganese and Nitrate in Groundwater by Biological Ribbon Technology

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地学前缘 2009年第S1期16卷 190-191页

作者： Yuchen Li,Yukun Ju School of Water Resources & Environment,china university of geosciences({3.),{3. 100083.china

The pollution of iron,manganese and nitrate in groundwater is a huge threat to human *** this study,column experiments of ceramic,manganese sand,ceramic sand,volcanic rock,quartz sand were *** and manganese contents of influent were 3.3.mg/L and 2.1 mg/*** the biofilm became mature,the highest iron and manganese removal rate achieved by manganese sand as a filter *** did a little worse than manganese sand,but other three filter material could not reach

关键词： removal of iron manganese and nitrate groundwater biological ribbon technology

Effect of Preparation Condition on Low-density PS Particle Size and Distribution

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Journal of university of Science and Technology beijing 2001年第4期8卷 274-276页

作者： Huili Fan, Jiemin Liu, Meijuan Wen, Weixue Tian Applied Science School. university of Science and Technology beijing.beijing {3. china Applied Science School University of Science and Technology Beijing Beijing 100083 China

The preparation conditions were studied in order to obtain smaller, narrow size-distributed and low-density polystyrene (PS) micro-particles by suspension polymerization. The results show that some of preparation conditions, the shape and position of stirrers, and stirring rate etc., have important influence on the size and distribution of particles. The preparation conditions must be carefully designed and controlled in order to obtain high-quality PS beads. A bow-shaped stirrer is helpful to produce small-sized particles and narrow size distribution, and the upper edge of a stirrer should be set to the same level as the surface of mixture, and the stirring rate should be controlled in the range of 520-600 r/min.

关键词： low-density micro-particles suspension polymerization preparation conditions

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

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

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

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

Thermodynamic Properties of Mn-P and Fe-Mn-P Melts

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International Journal of Minerals,Metallurgy and Materials 2000年第1期14卷 10-13页

作者： Jian Zhang Rong Zhu 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 and the coexistence theory of metallic melts structure involving compound formation, the cal- culating models of mass action concentrations for Mn-P and Fe-Mn-P melts have been formulated. The calculated mass action concen- trations agree well with the corresponding measured activities, this in turn shows that the deduced models can reflect the structural char- acteristics of the melts concerned and there isn't any saturation of phosphorus in both melts.

关键词： activity dephosphorization the coexistence theory mass action concentration