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Density functional theory study of the reaction paths of reactions of CH3C（O）O2.radicals with HO2.in the gas phase

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Progress in Natural Science:Materials International 2006年第12期16卷 1269-1274页

作者： ZHOU Yuzhi~ 1.2., ZHANG Shaowen~1.and LI Qianshu~1.*(1. State Key Laboratory of Explosion Science and Technology, {1. {1. of Technology, {1. 1.0081. China 2. {1. {1. of Education, {1. 1.0044, China) [a]State Key Laboratory of Explosion Science and Technology Beijing Institute of Technology Beijing China [b]beijing {1. of Education Beijing China

A DFT study on the reactions between CH_3C（O）O_2.nd HO_2.adicals has been carried out. It is suggested that both the triplet and singlet potential surfaces involve a complex mechanism with the formation of loosely bound intermediate complexes of reactants and products. The reaction prefers to occur on the triplet surface to produce peracetic acid (CH_3C（O）O_2.) and triplet O_2.olecule. The CH_3C（O）O_2. can further convert into CH_3C（O）O and HO radicals.

关键词： acetyl peroxy radicals HO2.radicals reaction mechanism DFT.

Three industries and wastewater and COD discharge of beijing

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Journal of Environmental Sciences 2000年第4期12卷 474-477页

作者： WANG Yan 1. WANG Hong rui 2. NING Da tong 2.(1. beijing Municipal Research {1. of Environmental Protection, beijing 1.0037, China 2. {1. of Environmental Sciences, beijing Normal University, beijing 1.0875, China) 北京市环境保护所北京 1 0 0 0 3 北京师范大学北京 1 0 0 875

With the swift development of economy, the water quality of beijing is becoming worse day by day and hampers the sustainable development obviously. In this paper, the current conditions of the municipal wastewater structure in the industrial sectors are analysed and discussed in terms of the indicators, such as direct wastewater\|discharge coefficient, complete wastewater\|discharge coefficient, direct discharge coefficient of COD and complete discharge coefficient of COD, by taking a year of 1.90s as the base year. Some countermeasures are studied and the corresponding recommendations are put forward in order to improve the water environment in beijing. This provides a scientific ground for coordinating the relationship between the aquatic environment and economic growth in this city.

关键词： direct wastewater discharge coefficient (DWDC) complete wastewater discharge coefficient (CWDC) direct discharge coefficient of COD(DDC of COD) complete discharge coefficient of COD (CDC of COD)

Research progress in synthesis and catalysis of polyoxometalates

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Progress in Natural Science:Materials International 2005年第5期15卷 385-394页

作者： GONG Yun1. HU Changwen1.* and LIANG Hong2.1. Department of Chemistry, School of Science, the {1. for Chemical Physics, {1. {1. of Technology, {1. 1.0081. China 2. Chemical Industry Press, {1. 1.002., China) Department of Chemistry School of Science the Institute for Chemical Physics Beijing Institute of Technology Beijing 100081 China Chemical Industry Press Beijing 100029 China

Recent progress in the synthetic chemistry and catalysis of polyoxometalates (POMs) is reviewed. The novel POMs and their derivatives emerging in nearly three years (2.02.2.04) are introduced, including POMs with novel structure, POMs-organic hybrid compounds and host-guest complexes. Our review is focused on the elaboration of POMs' supramolecular chemistry.

关键词： polyoxometalates hybrid host-guest structure supramolecule catalysis.

The numerical method for three-dimensional impact with friction of multi-rigid-body system

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Science China(Physics,Mechanics & Astronomy) 2006年第1期49卷 102-118页

作者： ZHAO Zhen1.2. LIU Caishan2.& CHEN Bin2.1. beijing {1. of Graphic Communication, beijing 1.2.00, China 2. Department of Mechanics & Engineering Science, Peking University, beijing 1.0871. China beijing {1. of Graphic Communication Beijing 102600 China Department of Mechanics & Engineering Science Peking University Beijing 100871 China

The differential equations for planar impacts reduce to an algebraic form, and can be easily solved. For three dimensional impacts with friction, there is no closed-form solution, and numerical integration is required due to the swerve behavior of tangential impulse during collisions. The dynamic governing equations in the impact process are built up in impulse space based on the Lagrangian equation in this paper. The coefficient of restitution defined by Poisson is used as the condition of impact termination. A valid nu- merical method for solving three-dimensional frictional impact of multi-rigid body system is established. The singular cases of tangential movement in sticking point are especially noticed and analyzed. Several examples are present to reveal the different kinds of tan- gential movement modes varied with the normal impulse during collision.

关键词： multi-rigid body, impact, friction.

Existence of the solutions and the attractors for the large-scale atmospheric equations

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Science China Earth Sciences 2006年第6期49卷 650-660页

作者： HUANG Haiyang1.& GUO Boling2.1. Department of Mathematics, {1. Normal University, {1. 1.0875, China 2. {2. of Applied Physics and Computational Mathematics, {1. 1.0080, China 1. Department of Mathematics Beijing Normal University Beijing 100875 China 2. {1. of Applied Physics and Computational Mathematics Beijing 100080 China

In this paper, firstly, the proper function space is chosen, and the proper expression of the operators is introduced such that the complex large-scale atmospheric motion equations can be described by a simple and abstract equation, by which the definition of the weak solution of the atmospheric equations is made. Secondly, the existence of the weak solution for the atmospheric equations and the steady state equations is proved by using the Galerkin method. The existence of the non-empty global attractors for the atmospheric equations in the sense of the Chepyzhov-Vishik’s definition is obtained by constructing a trajectory attractor set of the atmospheric motion equations. The result obtained here is the foundation for studying the topological structure and the dynamical behavior of the atmosphere attractors. Moreover, the methods used here are also valid for studying the other atmospheric motion models.

关键词： atmosphere equations, weak solution, trajectory attractor, global attractor, equilibrium.

Calculating soil moisture by remote sensing and analyzing hydrologic cycle process in the Yellow River basin

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Science China(Technological Sciences) 2004年第z1期47卷 1-13页

作者： YANG Shengtian1.& LIU Changming1. 2.1. School of Environmental Sciences, {1. Normal University, {1. 1.0875, China 2. {2. of Geographic Science and Natural Resources Research, {1. 1.01.1. China beijing Normal Univ Sch Environm Sci Beijing 100875 Peoples R China Inst Geog Sci & Nat Resources Beijing 100101 Peoples R China

Based on the AVHRR pathfinder remote sensing data, soil moisture, precipitation and evaporation during the period of 1.82.1.98, soil moisture of all layers of soil-profile (0—1.m) in the Yellow River basin over the 1. years are calculated by the remote sensing model of calculating soil water. The Yellow River basin is divided into seven subcatchments as control sections at the location of six hydrologic stations (Lanzhou, Toudaoguai, Longmen, Sanmenxia, Huayuankou and Lijin). After calculating soil moisture and obtaining runoff data and precipitation data, the dynamical features of hydrological cycle in the Yellow River basin are analyzed for the period from 1.82.to 1.88 using water balance method. The conclusions are as follows: It is feasible to calculate the soil water on the macro-scale, in the soil profile with temporal continuity by means of remote sensing and survey in land. Some values of the key water cycle factors in the Yellow River are obtained, which include the annual precipitation of 4000 km3, the evapotranspiration of 3000-3500 km3, and the soil moisture transformation of ?500- 500 km3. Consequently, we analyzed the process of the water cycle in the Yellow River over the 1. years, and the results show that the segment upstream of Lanzhou city is a relatively humid region, and the area of internal waters and the reaches of Shanshan is the most desiccated region. Therefore, the runoff in the depth process is intensive and the runoff-generating process is weak in more arid regions.

关键词： the Yellow River, soil moisture, remote sensing, hydrologic cycle.

Mineralogy and crystal structure determination of Mg-fillowite

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Science China Earth Sciences 2005年第5期48卷 635-646页

作者： MA Zhesheng 1., SHI Nicheng 1.& YE Danian 2.1. China University of Geosciences, {1. 1.0083, China 2. {1. of Geology, Chinese Academy of Sciences, {1. 1.002., China 1. China University of Geosciences 100083 Beijing China 2. {1. of Geology Chinese Academy of Sciences 100029 Beijing China

Accurate crystal structure determination of complex phosphate Mg-fillowite ? Na2.a(Mn4Mg2.e)7[PO4]6 has been finished. Mg-fillowite occurs in muscovite-pegmatite in the Altay area, Xinjiang, China. It is of the trigonal lattice, with space group R-3, unit cell a=1.51.3(3) nm, c=4.31.1.2. nm, V=8.5736 nm3, Z = 1.. The R-factor of the determination accuracy is R (I > 2. ( I )) = 0.0776. The cationic polyhedra consist of two kinds of structural units: compound col- umn and screw column. In three-dimensional space, they are linked with each other through corner sharing or edge sharing to build the entire structure. There are 45 atoms in an asymmetric unit and 72. atoms in a unit cell. In terms of types and connection manners of the coordination polyhedra, the degree of complicity is rarely seen in all mineral crystal structures. Study of such a structure is significant for the classification of phosphate and the building rule of coordination polyhedra in a complex crystal structure.

关键词： Mg-fillowite, complex phosphate, crystal structure, coordination polyhedron.

Biasing fluctuation model for directional stepping motion of molecular motor

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Chinese Science Bulletin 1998年第22期43卷 1879-1882页

作者： BAO Jingdong 1.and ZHUO Yizhong 2.1. {1. Meteorological College, {1. 1.0081. China 2. China {2. of Atomic Energy, beijing 1.2.1., China beijing Meteorological College Beijing China China institute of Atomic Energy Beijing China

The biasing fluctuation model with a colored noise is presented to study the directional stepping motion of the molecular motor. The expression of probability current is obtained in the adiabatic approximation. The fo... 详细信息

关键词： molecular motor stepping motion biasing force colored noise Langevin equation.

Randomization of protein encoding gene during species evolution

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Chinese Science Bulletin 1998年第4期43卷 299-303页

作者： GE Weiwen 1.and HE Fuchu 2.1. {1. of Hygiene and Environment Medicine, Tianjin 300050, China 2. {1. of Radiation Medicine, {2. 1.0850, China institute of Hygiene and Environment Medicine Tianjin China institute of Radiation Medicine Beijing China

Employing chi_square test, the authors observed the bias of 4 kinds of bases’ locating in 3 codon positions in gene sequence, and proved that there is a positive correlation between higher chi_square value and protein coding structure. By this, the observation that genes undergo progressive reduction in chi_values along evolution direction will reflect the progressive randomization of gene structures and the loss of the characteristics of protein coding sequences. The result proposed that during the evolution of life, genes are unexpectedly degenerating.

关键词： chi_square test gene sequence randomization evolution.