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Science china Chemistry 2007年第4期50卷 468-475页

作者： WANG ZhengWu1.& YI XiZhang2 1.Department of Food Sciences & Technology, school of Agriculture and Biology, Shanghai Jiao Tong {1., Shanghai 200240, china 2 Institute of Theoretical Chemistry, Shandong {1., jinan 2501.0, china 1. Department of Food Sciences & Technology School of Agriculture and Biology Shanghai Jiao Tong University Shanghai 200240 China 2. Institute of Theoretical Chemistry Shandong University Jinan 250100 China

By using the binary anionic/cationic surfactants system CH3(CH2)nOSO_3/CH3(CH2)nN+(CH3)3 as an ex-ample, the molecular exchanging energy (ε) of adsorption on the surface monolayer of aqueous solu-tion has been studied. ε can be obtained with two methods. One is from the relationship between ε and the molecule interaction parameter (β). This relationship is founded by considering that the adsorption of mixed surfactants on the surface monolayer of solution satisfies the dimensional crystal model condition under which β can be obtained by testing the surface tension of solution. The other is directly from the molecular structure of surfactants with the Lennard-Jones formula. The results for the studied system show that these two methods coincide well.

关键词： surfactant molecule exchanging energy dimensional crystal model

Large second-order optical nonlinearities of s-triazine derivatives: View from micro molecules to macro crystals

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Science china Chemistry 2005年第3期48卷 203-209页

作者： FANG Qi1. LEI Hong2, CUI Yuezhi3, HUANG Zhenli4, XUE Gang1.& YU Wentao1.1. State Key Laboratory of Crystal Materials, Shandong university, {1. 2501.0, china 2. school of Information Science and Engineering, Shandong university, {1. 2501.0, china 3. Department of Chemical Engineering, Light Industry College of Shandong, {1. 2501.0, china 4. Key Laboratory of Biomedical Photonics, Ministry of Education, Huazhong university of Science and Technology, Wuhan 430074, china 1. State Key Laboratory of Crystal Materials Shandong University 250100 Jinan China 2. school of Information Science and Engineering Shandong University 250100 Jinan China 3. Department of Chemical Engineering Light Industry College of Shandong 250100 Jinan China 4. Key Laboratory of Biomedical Photonics Ministry of Education Huazhong University of Science and Technology 430074 Wuhan China

Three s-triazine derivatives have been synthesized and their structures been de-termined. These are Compound I: 2,4-dimethyl-6-(p-N,N-dimethylaminostyryl)-s-triazine (abbre-viated to NMe-1., Compound II: 2,4-dimethyl-6-(p-N,N-diethylaminostyryl)-s-triazine (to NEt-1., and Compound III: 2-methyl-4,6-bis(p-N,N-dimethylaminostyryl)-s-triazine (NMe-2). NMe-1.and NEt-1.molecules belong to the D-π-A type with a one-dimensional charge-transfer character. NMe-1.crystallizes to centrosymmetric P1.space group, while NEt-1.to non-centrosymmetric polar Cc space group with all of the molecular charge-transfer axes taking the same orientation. Under the irradiation of 1.64 nm fundamental laser, NEt-1.powder crystals radiate a 2-order harmonic light with an intensity 46.8 times that of urea. The Λ typed NMe-2 molecule, which has a two-dimensional charge-transfer character, crystallizes to polar P21.space group. Its powder crystals exhibit a 2-order harmonic intensity 46.2 times that of urea. The quantum chemical cal-culations and tensor analyses have been carried out to reveal the dependence of the macro 2-order nonlinear optical (NLO) efficiency on the micro 2-order NLO coefficients (β) and on the crystalline packing styles.

关键词： s-triazine derivatives, synthesis, structure, SHG intensities of crystals, βvalues of molecules.

MULTI-DIMENSIONAL REFLECTED BACKWARD STOCHASTIC DIFFERENTIAL EQUATIONS AND THE COMPARISON THEOREM

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Acta Mathematica Scientia 2010年第5期30卷 1819-1836页

作者：吴臻消华 school of Mathematics Shandong University school of Mathematics and Statistics Shandong University at Weihai

In this article, we study the multi-dimensional reflected backward stochastic differential equations. The existence and uniqueness result of the solution for this kind of equation is proved by the fixed point argument where every element of the solution is forced to stay above the given stochastic process, i.e., multi-dimensional obstacle, respectively. We also give a kind of multi-dimensional comparison theorem for the reflected BSDE and then use it as the tool to prove an existence result for the multi-dimensional reflected BSDE where the coefficient is continuous and has linear growth.

关键词： backward stochastic differential equations comparison theorem local time

Water impoundment modes of flood utilization for the Songnen Plain

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Science china(Technological Sciences) 2008年第5期51卷 506-516页

作者： XU ShiGuo1.& LI WenYi1.2 1.Dalian university of Technology, Dalian 1.6024,{1. 2 Yellow River Shandong Bureauy, jinan 25001.,{1. Dalian university of Technology Dalian 116024 China Yellow River Shandong Bureauy Jinan 250011 China

Taking the Songnen Plain as the research region and basing on the structural division of river water resources, the impounding models of flood water utilization are proposed. Considering the water requirement, potential impoundage and the degree of risk, two modes of the flood water utilization are developed: full impounding and partial impounding. A risk assessment method is put forward according to variation of the flood storage capacity before and after impounding water. A representative hydrological year is taken as an example to analyze the application of the model at the downstream of the Nenjiang River. It is found that the model is very useful for the flood utilization and protection. For flood utilization, the spring drought can be relieved and the risk of impounding water is also acceptable. For flood protection, the river flood peak can be largely reduced and the impounding water can increase the river discharge at the low water period, at the same time the structure of river water resources can be improved as well.

关键词： river water resources flood water utilization detention basin Songnen Plain

Comparison of temporal and Spatial Characteristics of Ozone Pollution at Ground Level in the Eastern china

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Chinese Journal of Population,Resources and Environment 2006年第3期4卷 51-57页

作者： Liu Houfeng1.2 1. Shandong Normal university, {1. 25001., china 2. Chinese Research Academe of Environmental Sciences, Beijing 1.001., china Shandong Normal university Jinan 250014 China Chinese Research Academe of Environmental Sciences Beijing 100012 China

Monitoring data from ozone（O3） automatic stations in three typical cities with different climatic areas in the southern and northern parts of eastern china are used to analyze temporal and spatial characteristics of ozone pollution at ground level. The results show that ozone pollution level has distinct regional differences and the concentration in the suburbs is higher than that in the urban areas. The seasonal variation of ozone concentration in different climatic areas is greatly affected by the variation of precipitation. Ozone concentration in Shenyang and Beijing , in the temperate zone, has one perennial peak concentration, occurring in early summer, May or June. Ozone concentration in Guangzhou, in sub-tropical zone, has two peak values year round. The highest values occur in October and the secondary high value in June. The ozone season in the south is longer than that in the north. The annual average daily peak value of ozone concentrations in different climates usually occur around 3 pm. The diurnal variation range of ozone concentration declines with the increase of latitude. Ozone concentration does not elevate with the increase of traffic flow. Ozone concentration in Guangzhou has a distinct reverse relation to CO and NOx. This complicated non-linearity indicates that the equilibrium of ozone photochemical reaction has regional differences. Exceeding the rate of Beijing＇s lh ozone concentration is higher than that of Guangzhou, whereas the average 8h ozone level is lower than that of Guangzhou, indicating that areas in low latitude are more easily affected by moderate ozone concentrations and longer exposure. Thus, china should work out standards for 8h ozone concentration.

关键词： ozone temporal and spatial characteristics 8h concentrations weekly variation

Thermochemical Evaluation of Combustion Synthesis of Al_2O_3/B_4C Composite

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International Journal of Minerals,Metallurgy and Materials 1998年第2期12卷 90-92页

作者： Yonghe Liu~(1.2)) Sheng Yin~(1.) Weijing Zhang~(1.) Hoyi Lai~(1.) 1. Materials Science and Engineering school, UST Beijing, Beijing 1.0083,{1. 2) school of Materials Science and Engineering, Shandong university of Technology, jinan 25001. Materials Science and Engineering school UST Beijing Beijing 100083 China school of Materials Science and Engineering Shandong University of Technology Jinan 250014 China

The equilibrium phase and adiabatic temperature for combustion synthesis of Al_2O_3/B_4C employing Al, B_2O_3 and C as starting materials is analyzed by both conventional and CALPHAD method. The adiabatic temperature calculed by CALPHAD method is significantly lower than that obtained by conventional method. The CALPHAD calculation also reveals that the equilibrium phases presented at the adiabatic temperature are different to the desired composites. The adiabatic temperature in this system can be lowered by introducing Al_2O_3 as diluents. The maximum amount of Al_2O_3 that can be added to the system while maintain a self-sustaining combusion mode is 1.3 mol.

关键词： thermochemical evaluation SHS Al_2O_3/B_4C composite

The Stamping Formability of AZ31.Magnesium Alloy Sheet Improved by Equal-channel Angular Pressing

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Journal of Wuhan university of Technology(Materials Science) 2010年第2期25卷 234-237页

作者：刘英 Department of Material Science and Engineering Jinan University

Equal channel angular pressing （ECAP） processing and annealing were applied to the AZ31.magnesium alloy sheets to evaluate the potential improvement in the mechanical properties and formability. The ECAP experiment was conducted at 300 ℃ in a die having an included angle of 90o between two channels by the BCZ route with the sheets rotated by 90°about the normal axis of plate plane. The tensile tests and conical cup tests were conducted at various temperatures from 20 to 250 ℃. The experimental results indicated that improving the working temperatures could lead to the soft in the material and the enhancement of ductility. Comparatively, the ECAPed AZ31.alloy sheets showed the lower yield strength and smaller conical cup value （CCV） than the unECAPed counterpart in the room temperature. The difference in yield strength between them became small in the elevated temperature, but the ECAPed samples still had the smaller CCV value, implying the improved formability. The texture of the AZ31.alloy sheets could be modified by ECAP and the decrease in the yield strength and more uniform deformation realized in the material, so the formability of AZ31.alloy sheets was improved.

关键词： AZ31.magnesium alloy sheets equal-channel angular pressing mechanical properties conical cup value (CCV)

Release of Nestorone from Biodegradable Rods System in vitro

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Journal of Wuhan university of Technology(Materials Science) 2010年第1期25卷 4-7页

作者：曹成波 school of Chemistry and Chemical Engineering Shandong University

To study the controlled effect of poly （lactic acid）（PLA）, poly lactic-coglycolic （PLGA） and ethylenediamine （EDA）-maleic anhydride （MAH） modified PLA （EMPLA） for in vitro release of nestorone, rods were prepared using the solvent evaporation method. Amount of drug release in vitro was determined by UV spectrophotometry. Effects of rods diameter, the molecular weight of PLA, the drug percentage and the hydrophilicity of polymers on the release of biodegradable nestorone rods in vitro were investigated. It is indicated that the controlled effect of the biodegradable rods for the release of nestorone in vitro is good. The amount of drug released every week from rods in different diameter is similar to one another. The amount of drug released every week and the accumulative drug released during 1. week were almost in direct proportion with the drug percentage of the rods. The amount of drug released every week is increased as the decreasing of PLA molecular weight. As the hydrophlicity of polymer is improved, the rate of drug release every week is accelerated. The studies show that the plausibility of controlled release of nestorone from PLA, PLGA and EMPLA rods imply the possibility of their application as a controlled delivery system for nestorone. The results show that the greater the molecular weight of PLA is, the slower its degradation is and the slower the drug released; the greater the percentage of nestorone is, the more quickly the drug release. An increase of the hydrophilicity of the polymers will increase their degradation rate and leads to a fast drug release. Anyhow, these rods systems should be further evaluated in vivo.

关键词： nestorone PLA PLGA EMPLA rods in vitro release

The optical near-field speckles and their first order statistics on the basis of the integral equations of electromagnetic field

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Science china(Physics,Mechanics & Astronomy) 2004年第3期47卷 365-380页

作者： CHENG Chuanfu1. 2, SONG Hongsheng2, LIU Chunxiang2, REN Xiaorong2, ZHANG Ningyu3, TENG Shuyun1.& XU Zhizhan1.1. Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P. O. Box 800-21., Shanghai 201.00, china 2. Department of Physics, Shandong Normal {1., jinan 25001., china 3. Shandong Institute of Architecture and Engineering, jinan 25001., china 1. Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences P. O. Box 800-211 201800 Shanghai China 2. Department of Physics Shandong Normal University 250014 Jinan China 3. Shandong Institute of Architecture and Engineering 250014 Jinan China

From Helmholtz equation of the harmonic electromagnetic waves, the integral equations of the light field at the medium boundaries are obtained by use of the Green's theorem and are discretized into linear equation set with the values of the light field and its derivative as the unknowns. On solving the linear equation set, we realize the rigorous computations of the light fields at the boundaries. Then the intensities of the light waves scattered by the random self-affine fractal surfaces in the optical near-field are calculated, and the propagation characteristics, the evolutions of the contrast and the intensity probability density function of the near-field speckles are studied in detail. The near-field speckles are much different from the conventional speckles in the diffraction regions and in the imaging systems. There are obvious local fluctuations in the intensity distributions of the near-field speckles and such fluctuations disappear after propagating a distance of one wavelength from the medium surfaces. For the random surfaces with smaller lateral correlation lengths, the speckle contrasts approach the saturation values and the speckle fields approach Gaussian distribution within the near-field, while for the random surfaces with larger lateral correlation lengths, such evolutions become comparatively slow.

关键词： speckle, near-field optics, first order statistics, Green's function.

Function S-rough sets and security-authentication of hiding law

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Science in china(Series F) 2008年第7期51卷 924-935页

作者： SHI KaiQuan1.2 & ZHAO JianLi3 1.school of Mathematics and Computer Sciences, Longyan {1., Longyan 364000, china 2 school of Mathematics and System Sciences, Shandong {1., jinan 2501.0, china 3 school of Mathematics Science, Liaocheng {1., Liaocheng 252059, china 1. school of Mathematics and Computer Sciences Longyan University Longyan 364000 China 2. school of Mathematics and System Sciences Shandong University Jinan 250100 China 3. school of Mathematics Science Liaocheng University Liaocheng 252059 China

Function S-rbugh sets are defined by R-function equivalence class, which have dynamic characteristic. Function S-rough sets have dynamic characteristic, law characteristic and law-hiding characteristic. Function S-rough sets can generate f-hiding law and f-hiding law. By engrafting, crossing, and penetrating between the information security theory and function S-rough sets, the security hiding and the authentication of f-hiding law and f-hiding law are given respectively in this paper. The fusion and share between function S-rough sets and information security theory is a new research direction of the application of information law in information system.

关键词： function S-rough sets law-hiding elliptic curve the security-authentication of hiding law