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Study on the electric double layer of a cylindrical reverse micelle with functional theoretical approach

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Science china Chemistry 2006年第3期49卷 219-224页

作者： WANG Zhengwu1,2. GUO Baomin2. ZHANG Gexin1 & YU Huixin1 1. key laboratory of Industrial Biotechnology of{2., Southern Yangtze University, Wuxi 2.4036, china 2. School of Chemical and material Engineering, Southern Yangtze University, Wuxi 2.4036, china key laboratory of Industrial Biotechnology of{2. Southern Yangtze University Wuxi China School of Chemical and material Engineering Southern Yangtze University Wuxi China

The iterative method in functional analysis is applied to looking for asolution of the Poisson-Boltzmann equation in order to describe the problems of the distribution ofthe potentials in the electric double layer (EDL) inside the water pool for a cylindrical inversemicelle. Potentials as a function of the position of a particular point in EDL are computed, whichdisplay a quantitative agreement with those from earlier calculation of Debye and Huckel in the caseof low potentials. But it is also shown that in the higher-potential range the iterativecalculations can give more accurate results. These results indicate the utility of this functionalanalysis technique in the description of the properties of EDL for a cylindrical inverse micelle.

关键词： cylindrical reverse micelle, electrostatic double layer, Poisson-Boltzmann equation, functional analytic theory.

Two-dimensional thermoelasticity solution for functionally graded thick beams

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Science china(Physics,Mechanics & Astronomy) 2006年第4期49卷 451-460页

作者： Lü Chaofeng1, CHEN Weiqiu1 & ZHONG Zheng2.1. Department of Civil Engineering, Zhejiang University, Hangzhou 31002., china 2. key {2. of Solid Mechanics of ministry of education, School of Aerospace Engineering and Ap- plied Mechanics, Tongji University, Shanghai 2.0092. china Department of Civil Engineering Zhejiang University Hangzhou China key laboratory of Solid Mechanics of{2. School of Aerospace Engineering and Applied Mechanics Tongji University Shanghai China

Two-dimensional thermoelasticity analysis of functionally graded thick beams is presented using the state space method coupled with the technique of differential quadrature. material properties vary continuously and smoothly through the beam thickness, leading to variable coefficients in the state equation derived from the elasticity equations. Approximate laminate model is employed to translate the state equation into the one with constant coefficients in each layer. To avoid numerical instability, joint coupling matrices are introduced according to the continuity conditions at interfaces in the approximate model. The differential quadrature procedure is applied to discretizing the beam in the axial direction to make easy the treatment of arbitrary end conditions. A simply-supported beam with exponentially varying material properties is considered to validate the present method. Numerical examples are performed to investigate the influences of relative parameters.

关键词： state equation differential quadrature approximate laminate model joint coupling matrices thermal stresses.

Effect of Cooling Rate on the Microstructure of ZA48 Alloy

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Journal of Wuhan University of Technology(materials Science) 2010年第5期25卷 811-813页

作者：王杰芳谢敬佩 School of Physics and Engineering The Key Laboratory of Material Physics of the Ministry of Education of China Zhengzhou University The College of materials Science & Engineering Henan University of Science and Technology

The effect of cooling rate on the microstructure of ZA48 alloy was investigated. The alloy was prepared using a relatively simple technique, i e, rapid cooling of the melt in a steel wedge mould. The dependence of microstructure on the cooling rate （about 40 to 10^3 K/s） was determined by the secondary dendrite arm space size measurement, optical microscopy（OM）, and transmission electron microscopy （TEM）. It is found that the matrix structure over a large cooling rate is composed of α-Al dendrite and eutectoid （α＋η）, the size of α-Al dendrite decreases with increasing cooling rate. The relationship between the cooling rate and the secondary dendrite arm space size has been established. TEM shows that a large number of small and dispersed precipitations can be seen in the primary α phase of tip region. Electron diffraction pattern shows that the precipitate phase is Zn3Mg2.phase.

关键词： cooling rate microstructure secondary dendrite arm space size precipitation

Optimal reactions for the synthesis of superheavy nucleus ^(2.0)Hs

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Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 641-648页

作者： LIU Zuhua1,3 & BAO Jingdong1,2.1. key laboratory of Beam Technology and {2. Modification of ministry of education, Beijing Normal University, Beijing 100875, china 2. Physics Department, Beijing Normal University, Beijing 100875, china 3. china Institute of Atomic Energy, Beijing 102.13, china key laboratory of Beam Technology and {2. Modification of ministry of education Beijing Normal University Beijing China china Institute of Atomic Energy Beijing China Physics Department Beijing Normal University Beijing China

The superheavy nucleus 2.0Hs is expected to be a “double-magic” deformed nucleus. We have calculated its cross sections of evaporation residue for the reactions 2.8Cm(2.Mg,4n)2.0Hs, 2.4Pu(30Si,4n)2.0Hs, 2.8U(36S,4n)2.0Hs and 2.6Ra(48Ca,4n)2.0Hs using a two-parameter Smoluchowski equation. It is found from our results that 2.6Ra(48Ca,4n)2.0Hs and 2.8U(36S,4n)2.0Hs are two optimal reactions for the synthesis of the superheavy nucleus 2.0Hs due to their large negative Q-values.

关键词： diffused fusion barrier,Smoluchowski equation,superheavy nuclei.

Efficiency of sediment transport by flood and its control in the Lower Yellow River

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Science china(Technological Sciences) 2004年第Z1期47卷 173-185页

作者： NI Jinren1, LIU Xiaoyong2. LI Tianhong1, ZHAO Ye’an3 & JIN Ling1 1. Department of Environmental Engineering, Peking University The key laboratory of Water and Sedi- ment Sciences,{2., Beijing 100871, china 2. General Institute of Water Resources and Hydropower Planning and Design, ministry of Water Re- sources, Beijing 100011, china 3. The Yellow River Conservancy Commission, zhengzhou 450003, china Department of Environmental Engineering Peking University Beijing China The key laboratory of Water and Sediment Sciences Ministry of Education Beijing China General Institute of Water Resources and Hydropower Planning and Design Ministry of Water Resources Beijing China The Yellow River Conservancy Commission Zhengzhou China

This paper presents the characteristics of sediment transport by flood in the Lower Yellow River with the reach from Huayuankou to Gaocun, which is regarded as a typical braided pattern. The Artificial Neural Network Model on Water Use for Sediment Transport (WUST) by flood was established based on the measured data from 1980 to 1998. Consequently, simulations of controlling process of sediment transport by flood were made in terms of the control theory under different scenarios. According to the situation of sediment transport by flood in the Lower Yellow River, Open-Loop control system and feedback control system were adopted in system design. In the Open-Loop control system, numerical simulations were made to reveal the relationship between average discharge of flood and the WUST with varying sediment concentrations. The results demonstrate that sediment concentration has significant influence on the controlling process of flood flow to WUST. It is practical and efficient to control WUST if sediment concentration is less than 2. kg/m3. In the feedback control system, controlling processes of sediment concentration and flood discharge for sediment transport were simulated respectively under given conditions, and it was found that sediment transport process could be controlled completely by sediment concentration and discharge at the inlet of the reach from Huayuankou to Gaocun. Using the same method, controlling processes of sediment transport by flood in other reaches in the Lower Yellow River were also simulated. For the case of sediment concentration being 2. kg/m3, the optimized controlling discharge ranges from 2.90 to 2.00 m3/s in the lower reach of Huayuankou. This study is also of significance to flood control and flushing sediment in the Lower Yellow River with proper operation modes of Xiaolangdi Reservoir.

关键词： the Lower Yellow River, flood, sediment transport, efficiency, simulation, control.

Discovery of double-peaking potassic volcanic rocks in Langshan Group of the Tanyaokou hydrothermal- sedimentary deposit, Inner Mongolia, and its indicating significance

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Science china Earth Sciences 2005年第6期48卷 822-833页

作者： PENG Runmin1, ZHAI Yusheng1, WANG Zhigang2.& HAN Xuefeng2.1. key laboratory of Lithospheric Tectonics and Lithoprobing Technology,{2., china University of Geosciences, Beijing 100083, china 2. Inner Mongolia Geological Prospecting Institute, ministry of Chemical Industry, Hohhot 010074, china Correspondences should be addressed to Peng Runmin key laboratory of Lithospheric Tectonics and Lithoprobing Technology Ministry of Education China University of Geosciences Beijing China Inner Mongolia Geological Prospecting Institute Ministry of Chemical Industry Hohhot China

It is revealed that the protolith of gray-light brown potash-feldspar-leucogranulites and granulites in the 2.d formation of the LG in Tanyaokou deposit are quartz kerotophyre of synsedimentary eruption based on the following facts and features: (1) The rocks look compact and homogeneous without obvious crystals with naked eyes; (2. they contain blastoporphyritic or glomeroporphyritic and blasto-crystalloclastic crystals consisting of quartz with wavy extinction and albite with obvious alteration and deformation; (3) they also contain radiated and fibrous blasto-microspherulitic texture and swallow-tailed bifurcate and blasto-hollow-skeleton crystal texture, representing the rapid cooling characteristic of the magma during submarine volcanic eruption; (4) the major chemical compositions of the rocks are: SiO2.= 70.80%―76.00%, K2. (4.83%―6.2.%)>Na2.(2.78%―3.80%), and K2.+Na2. = 8.63%―9.00%; and (5) their petro-chemical diagrams indicate that they are volcanic rocks. Together with the characteristic that they occur in the same sequence with potassic spilite (SiO2.= 46.12.―50.68%, K2. = 4.2.%―5.93%>Na2. = 2.15%―3.14%, K2.+Na2. = 6.51%―8.08%), it can be confirmed that the vol-canics occurring in the 2.d Formation of the LG in Tanyaokou district are double-peaking potas-sic volcanic rocks. The discovery, together with the tuffs with ore minerals and the distribution of lead isotopic as well as the value of Co/Ni of pyrites >1 showing the obvious endogenic metali-zation, can prove that the Tanyaokou deposit is an untypical SEDEX-type deposit formed in the extension fault basin in the Mesoproterozonic aulacogen of the northern margin of the North china Platform, and its metallogenesis is related to the synsedimentary volcanic activities and the hydrothermal exhalation, and both the ore-forming material source and volcanics came from mantle or lower crust. These facts mentioned above, together with the meta-volcanic rocks (double-peaking) found in the Dongshengmiao and Huog

关键词： extensional rift basin, double-peaking potassic volcanic rocks, Mesoproterozoic, the 2.d formation of LG, Tanyaokou deposit, Inner Mongolia.

On the variation of water resource structure in the Lower Yellow River

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Science china(Technological Sciences) 2004年第Z1期47卷 127-141页

作者： NI Jinren1, WANG Yudong1, QIAN Zhenghan1, LI Tianhong1 & ZHAO Yean2.1. Department of Environmental Engineering, Peking University The key laboratory of Water and Sedi- ment Sciences,{2., Beijing 100871, china 2. Institute of Hydraulic Research, Yellow River Conservancy Commission, zhengzhou 450003, china Department of Environmental Engineering Peking University Beijing China The key laboratory of Water and Sediment Sciences Ministry of Education Beijing China Institute of Hydraulic Research YellowRiver Conservancy Commission Zhengzhou China

In view of river functions and the Minimum Water Demand for River Ecosystem (MWDRE), the water resources in the Lower Yellow River is further divided into three portions, i.e. water available for ecosystem (WE), water exploitable for socioeconomic purposes (WS) and excess flood water (WF). Corresponding conceptions and practical significances are expounded in details. The annual amount of the three portions of water resources from 1950 to 2.01 is worked out on the basis of the daily hydrologic data, and the division of different portions is discussed. The results indicate that although the essential water demand for river functions is considered preferentially, the amount of the WE has decreased dramatically while its proportion increased gradually since the 1950s, and the shortage to the MWDRE increased markedly; both the amount and the proportion of the WS decreased notably. Since the 1990s, the actual water consumption for socioeconomic purposes in the lower reaches of the river basin has already exceeded the maximum amount of the WS and has to take over the WE which is already insufficient, hence not only the normal river functions are further disturbed and the river course shrinks greatly, but also the proportion and potential danger of the WF show no decreasing tendency in spite of the sharp decrease of upstream runoff.

关键词： the Yellow River, water resource structure, water available for ecosystem, water exploitable for socioeconomic purposes, excess flood water.

Investigation on Vibrational Spectra and Structures of 4-Mercaptopyridine Monomer and Its Dihydrate

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Chemical Research in Chinese Universities 2006年第1期22卷 90-93页

作者： CHENG Jian-bo 1,2., XUE Wei-qing 1 , ZHAO Bing 1** , ZHANG Gang 3 and GONG Bao-an 2.1. key laboratory for Supramolecular Structure and {2. of ministry of education, Jilin University, Changchun 130012. P. R. china 2. Science and Engineering College of Chemistry and Biology, Yantai University, Yantai 2.4005, P. R. china 3. State key laboratory of Theoretical and Computational Chemistry, Jilin University, Changchun 13002., P. R. china key laboratory for Supramolecular Structure and {2. of ministry of education Jiln University Changchun 130012 P. R. China Science and Engineering College of Chemistry and Biology Yantai University Yantai 264005 P. R. China State key laboratory of Theoretical and Computational Chemistry Jiln University Changchun 130023 P. R. China

The optimized molecular structures and vibrational frequencies of 4-mercaptopyridine(4MPY) monomer and its dihydrate were studied by means of the density functional theory(DFT), viz. B3LYP method with the 6-311++G(d,p) basis set. On the basis of the calculations, the assignments of the vibrational spectra of the monomer and the dihydrate were performed, and so were investigated the changes in the structure and the vibrational spectrum of the dihydrate as well as the intermolecular force resulting in the formation of the dihydrate. The calculated results show that each of the water molecule planes is vertical to the pyridine ring plane in the dihydrate that is formed via the H-bonds between 4MPY and water molecules. Furthermore, the structure and the vibrational spectrum of 4MPY can be consi- derably affected by the water molecules.

关键词： 4MPY Dihydrate Vibrational spectra DFT Molecular structure

The Design and Properties of G.656 Optical Fiber Waveguide Design

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Journal of Wuhan University of Technology(materials Science) 2007年第1期22卷 70-73页

作者：成煜 key laboratory of Silicate {2.s Science and Engineering Wuhan University of Technology Ministry of Education FiberHome Telecommunication Technologies Co. LTD WuHan 430074China

To prepare the G.656 optical fiber for the future＇s network, the methods of material design and waveguide design were applied to predict theoretic properties of the fiber. PCVD process was applied to manufacture the multi-layer GeO2. F co-doped SiO2.materials. The fiber properties were tested for the cut-off wavelength, MFD, dispersion, etc. The tested results agreed with the theoretic prediction.

关键词： G.656 Waveguide dispersion metro