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Phase relationship of complex multi-component system in chromate cleaner production

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Progress in Natural science:Materials International 2007年第7期17卷 845-850页

作者： Ge Xinlei~1 Wang Xidong~(1,3.*) Zheng Shili~2 Zhang Mei~1 Zhang Yi~2 (1.Department of Physical Chemistry,university of science and technology {3.,{3. 100083.china 2.Institute of Process Engineering,Chinese Academy of sciences,{3. 100080,china 3.college of Engineering,Peking university,{3. 100871,china) [a]Department of Physical Chemistry University of Science and Technology Beijing Beijing China [b]college of Engineering Peking University Beijing China [c]Institute of Process Engineering Chinese Academy of Sciences Beijing China

The phase relationships of the complex multi-component systems in the liquid-phase oxidization and separation process related with the chromate cleaner production are investigated theoretically and *** phase diagram of main system Fe- Cr2O4-KOH-O2of oxidization process and the relationship of its standard Gibbs free energy change with temperature are calculated.A se- ries of phase diagrams of the separation process at different temperatures,such as K（Na）OH-K（Na）2CrO4-H2O,KOH-KAlO2-H2O, K（Na）OH-K（Na）2CO3.H2O,K（Na）OH-K（Na）HCO3.H2O and K（Na）HCO3.K（Na）2CrO4-H2O have also been *** ex- periments are carried out to verify the calculated *** results showed that the sub-molten salt media are suitable for the oxidization and separation processes;FeCr2O4can be oxidized across a wide range of temperature;K（Na）2CrO4can be separated from K（Na）AlO2system at appropriate temperature and proper concentration;the crystallization of carbonate is easier than that of K（Na）2CrO4.

关键词： chromite chromate system thermodynamics calculation phase diagram

Multiparty simultaneous quantum identity authentication with secret sharing

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science china(Physics,Mechanics & Astronomy) 2008年第3期51卷 321-327页

作者： YANG YuGuang1,2,WEN QiaoYan3.& ZHANG Xing4,5 1 college of Computer science and technology,{3. university of technology,{3. 100022,china 2 State Key Laboratory of Information Security (Graduate university of the Chinese Academy of sciences),{3. 100049,china 3.School of science,{3. university of Posts and Telecommunications,{3. 100876,china 4 Institute of Electronic technology,Information Engineering university,Zhengzhou 450004,china 5 Trusted Computing Laboratory,{3. university of technology,{3. 100022,china college of Computer science technology Beijing University of Technology Beijing 100022 China State Key Laboratory of Information Security [Graduate university of the Chinese Academy of sciences] Beijing 100049 China School of science Beijing University of Posts Telecommunications Beijing 100876 China Institute of Electronic technology Information Engineering University Zhengzhou 450004 China Trusted Computing Laboratory Beijing University of Technology Beijing 100022 China

Two multiparty simultaneous quantum identity authentication (MSQIA) protocols based on secret sharing are presented. All the users can be authenticated by a trusted third party (TTP) simultaneously. In the first protocol,the TTP shares a random key K with all the users using quantum secret sharing. The ith share acts as the authentication key of the ith user. When it is necessary to perform MSQIA,the TTP generates a random number R secretly and sends a sequence of single photons encoded with K and R to all the users. According to his share,each user performs the corresponding unitary operations on the single photon sequence sequentially. At last,the TTP can judge whether the impersonator exists. The sec-ond protocol is a modified version with a circular structure. The two protocols can be efficiently used for MSQIA in a network. They are feasible with current technol-ogy.

关键词： quantum identity authentication secret sharing quantum cryptography

Output-back fuzzy logic systems and equivalence with feedback neural networks

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Chinese science Bulletin 2000年第7期45卷 592-596页

作者： LI HongxingDepartment of Mathematics, beijing normal university, beijing 100875, china Department of Mathematics Beijing Normal University Beijing China

A new idea, output-back fuzzy logic systems, is proposed. It is proved that output-back fuzzy logic systems must be equivalent to feedback neural networks. After the notion of generalized fuzzy logic systems is defined, which contains at least a typical fuzzy logic system and an output-back fuzzy logic system, one important conclusion is drawn that generalized fuzzy logic systems are almost equivalent to neural networks.

关键词： output-back fuzzy logic systems generalized fuzzy logic systems feedforward neural networks feedback neural networks.

Refraction of light in media

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science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 591-600页

作者： ZHANG Tao Key Laboratory of Beam technology and Material Modification of Ministry of Education, Institute of Low Energy Nuclear Physics, beijing normal university, beijing 100875,{3. beijing Radiation Center, beijing 100875,{3. Key Laboratory of Beam technology Material Modification of Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China

The roles of the magnetic field and electric field of the light are investigated when the light is refracted in the medium. The model of the electron cloud conductor is presented. Electron cloud in a molecule is treated as a conductor and the Faraday’s Law is applied to this conductor that is in the alternating magnetic field of the light. dBM/dt of the light gives rise to an alternating induced current on the electron cloud conductor, and the light exchanges energy, i.e. the refractive energy, with the elec- tron cloud conductor. Formulas of refractive index, which is the ratio of light speed in vacuum to that in the medium, are derived with this model. These formulas are tested with several mediums and Langevin’s diamagnetic susceptibility of helium gas, and the results are in good agreement with the measured data. The anisotropy and the nonlinearity of the refractive index are explained with the theory described in this work.

关键词： refractive index, light, speed, medium, propagation

A trust region algorithm for bilevel programing problems

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Chinese science Bulletin 1998年第10期43卷 820-824页

作者： LIU Guoshan 1, HAN Jiye 2 and WANG Shouyang 3.1. Department of Mathematics, beijing normal university, beijing 100875, china 2. Institute of Applied Mathematics, Chinese Academy of {3.s, beijing 100080, china 3. Institute of Systems {3., Chi Department of Mathematics Beijing Normal University Beijing China Institute of Applied Mathematics Chinese Academy of Sciences Beijing China Institute of Systems science Chinese Academy of Sciences Beijing China

A trust region algorithm is proposed for solving bilevel programming problems where the lower level programming problem is a strongly convex programming problem with linear constraints. This algorithm is based on a tr... 详细信息

关键词： bilevel programming problem trust region algorithm global convergence.

Linear operators preserving the generalized decomposable numerical range

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Chinese science Bulletin 1997年第1期42卷 22-26页

作者： LEI TiangangDepartment of Mathematics, beijing normal university, beijing 100875, china Department of Mathematics Beijing Normal University Beijing 100875 China

LET G be a subgroup of the symmetric group Sm. Denote by CG the set of all functions f: G→C. A function f∈CG is said to be positive semi-definite （p. s. d. ） if there exists c∈CG such that for all τ∈G. In particular, the irreducible complex characters of G are p. s. d. Let Cn×m denote the set of all n×m complex matrices. For f∈CG, the

关键词： decomposable numerical range linear operator positive semi-definite function generalized matrix function.

A distributed hydrological model with its application to the Jinghe watershed in the Yellow River Basin

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science china(Technological sciences) 2004年第z1期47卷 60-71页

作者： WANG Zhonggen1, ZHENG Hongxing1, LIU Changming1, , WU Xianfeng2 2 & ZHAO Weimin3.1. Key Laboratory of Water Cycle & Related Land Surface Processes, Institute of Geographic science and Natural Resources Research, Chinese Academy of sciences, beijing 100101,{3. 2. Institute of Environmental science, beijing normal university, beijing 100875,{3. 3. Water Resources Conservation Committee of Yellow River, Zhengzhou 450003.{3. Chinese Acad Sci Key Lab Water Cycle & Related Land Surface Proc Inst Geog Sci & Nat Resources Res Beijing 100101 Peoples R China beijing normal Univ Inst Environm Sci Beijing 100875 Peoples R China Water Resources Conservat Comm Yellow River Zhengzhou 450003 Peoples R China

For the purpose of water resources management in the Yellow River Basin with highly spatial difference, a daily distributed hydrological model was proposed, of which the determination of spatially-distributed parameters and model inputs processing were performed by means of GIS/RS. In the model, the computation of runoff yield was based on the topography index method and flow routing was modeled by Maskingum method. The operation of the model is followed by means of “command structure” technique based upon the topography of river network. A case study using the model was conducted for the Jinghe watershed, which locates at the middle Yellow River Basin. The simulation of the hydrological processes in 1996 has shown that water quantity balance errors were less than 5% and the Nash-Sutcliffe coefficient arrived at 0.7, indicating that the model structure is justifiable, and the precision of the model can satisfy the purpose of water resources management.

关键词： distributed hydrological model, structure and equation, GIS and RS, Jinghe Basin, Yellow River Basin.

Redevelopment of liftoff rates of saltating sand grains based on a simple optimization model

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science china Earth sciences 2010年第4期53卷 568-574页

作者： CHENG Hong & ZOU XueYong State Key Laboratory of Earth Surface Processes and Resource Ecology,beijing normal university,beijing 100875,china MOE Engineering Center of Desertification and Blown-sand Control,beijing normal university,beijing 100875,china Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education of china,beijing normal university,beijing 100875,china 1. State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China2. MOE Engineering Center of Desertification and Blown-sand Control Beijing Normal University Beijing 100875 China3. Key Laboratory of Environmental Change and Natural Disaster of the Ministry of Education of China Beijing Normal University Beijing 100875 China

This paper is a redevelopment result of liftoff rates of saltating sand grains based on our previous *** sand flow is a complex multi-phase flow because of a special two-phase gas-solid flow near ground *** extensive research on the movement of blowing sand,no model fully characterizes aeolian sand flow,and large differences often exist between simulations of aeolian sand movement and field *** key problem is a few of sufficient research on liftoff rates of saltating sand grains(also called the number of liftoff sand grains per unit time and per unit bed area).It is necessary to re-search in advance liftoff rates of saltating sand *** redeveloped liftoff rates of saltating sand grains by establishing an optimization model based on the flux of aeolian sand flow at different heights of the sampler in wind tunnel and the simulated capture of saltating sand grains by different heights of the sampler that are from different liftoff position(distance from the sampler) in order to revise previous inversion condition of liftoff rates of saltating sand *** rates increased rapidly with increasing wind *** frictional wind velocities of u=0.67,0.77,0.82,0.83.and 0.87 m s-1,liftoff rates were 3.40,954502,523.114,5499407,and 7696291 sand grain s-1 m-2,*** rates could be expressed as the square of the instantaneous frictional wind velocity and a constant(0.663. that differs from the critical(threshold) frictional wind velocity at which saltation *** our results require additional experimental validation and the simple optimization model must be improved,they nonetheless provide a strong basis for future research.

关键词： liftoff rates of saltating sand grains optimization model wind tunnel two-phase gas-solid flow

Isomerization of B_6,B_6^- and B_6^+ clusters

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science china Chemistry 2010年第1期53卷 202-209页

作者： WEI GongMin1,PU ZhiFeng2,ZOU Rong3.LI GuoLiang2,3.& LUO Qiong2,3.1Department of Physics,Capital normal university,beijing 100048,{3. 2State Key Laboratory of Explosion science and technology beijing Institute of technology,beijing 100081,{3. 3.enter for Computational Quantum Chemistry,South china normal university,Guangzhou 51063.,{3. 1. Department of Physics Capital Normal University Beijing 100048 China2. State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing 100081 China3. Center for Computational Quantum Chemistry South China Normal University Guangzhou 510631 China

The interconversions between isomers with the same spin multiplicity of neutral B6 and charged B6-and B6+ clusters have been investigated at the B3.YP/6-3.1+G level of theory,including determination of the minimum energy pathways with transition states connecting the corresponding reactants and *** dynamic calculations,26 isomers were optimized,including 11 novel *** order to further refine the energies,single-point B3.YP/6-3.1+G(3.f) calculations were carried out on the corresponding B3.YP/6-3.1+G geometries of all isomers of B6,B6-and B6+ and the corresponding isomerization transition *** stability of each isomer of B6(singlet and triplet states),B6-(doublet state) and B6+(doublet state) was analyzed from both thermodynamic and dynamic viewpoints.

关键词： B6 transition state intrinsic reaction coordinate barrier height