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Journal of Biomaterials and Nanobiotechnology 2010年第1期1卷 31-36页

作者： Sungmin Hong Ying-Nai Wang Hirohito Yamaguchi Harinibytaraya Sreenivasappa Chao-Kai Chou Pei-Hsiang Tsou Mien-Chie Hung Jun Kameoka Department of Electrical and Computer Engineering Texas A & M University College Station Texas USA Department of Molecular and Cellular Oncology University of Texas M. D. Anderson Cancer Center Houston Texas USA Department of Molecular and Cellular Oncology University of Texas M. D. Anderson Cancer Center Houston Texas USA.

We have applied Raster Image Correlation Spectroscopy (RICS) technique to characterize the dynamics of protein 53 (p53) in living cells before and after the treatment with DNA damaging agents. HeLa cells expressing Green Fluores-cent Protein (GFP) tagged p53 were incubated with and without DNA damaging agents, cisplatin or eptoposide, which are widely used as chemotherapeutic drugs. Then, the diffusion coefficient of GFP-p53 was determined by RICS and it was significantly reduced after the drug treatment while that of the one without drug treatment was not. It is suggested that the drugs induced the interaction of p53 with either other proteins or DNA. Together, our results demonstrated that RICS is able to detect the protein dynamics which may be associated with protein-protein or protein-DNA interactions in living cells and it may be useful for the drug screening.

关键词： Raster Image Correlation Spectroscopy Diffusion coefficient p53 DNA Damage

Estimation of overall heat transfer coefficient of cooling system in RF capacitive hyperthermia

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Journal of Biomedical Science and Engineering 2013年第5期6卷 509-517页

作者： Seyed Ali Aghayan Dariush Sardari Seyed Rabii Mahdi Mahdavi Mohammad Hasan Zahmatkesh Department of Engineering Science and Research Branch Islamic Azad University Tehran Iran Department of Medical Physics Shahid Beheshti University Tehran Iran Department of Medical Physics Tehran University of Medical Science Tehran Iran

The study presented in this article involves the estimation of the overall heat transfer coefficient of cooling system in RF capacitive hyperthermia treatment using inverse problem based on the conjugate gradient method to provide improved distribution of temperature. The temperature data computed numerically from the direct problem using the finite difference time domain method are used to simulate the temperature measurements. The effects of the errors and sensor positions upon the precision of the estimated results are also considered. The results show that a reasonable estimation of the unknown can be obtained. Finally, measurements in a tissue-equivalent phantom are employed to appraise the reliability of the presented method. The comparison of computed data with measurements shows a good agreement between numerical and experimental results.

关键词： Estimation Hyperthermia Inverse Problem Phantom Overall Heat Transfer coefficient

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2006年北京春季气溶胶吸收系的分离研究

气候变化研究进展 2008年第z1期4卷 37-41页

作者：潘小乐颜鹏汤洁 Chinese Academy of Meteorological Sciences Beijing 100081China

A statistic regression approach was used to estimate the wavelength exponents of black carbon(BC)and dust particles,and further to separate the contributions of the two types of aerosols to the total light absorption coefficient measured in the Beijing urban area in the spring of 2006.The results show that the wavelength exponent(α)of black carbon aerosol at urban site was approximately-0.***.which is in agreement with the value of-0.8±0.2 reported in related studies.The decoupling analysis of the measured light absorption coefficients during the three floating dust periods(March 25,March 27,and April 9)demonstrates that,on average,the light absorption caused by dust particles took up about 32.8% of the total light absorption at 520 nm wavelength,and by black aerosol more than 60%.This indicates that the black carbon was still the major contributor to the total aerosol light absorption in Beijing urban area even during the floating dust periods.

关键词： dust particle black carbon absorption coefficient wavelength exponent

The Analysis of Limitation of Engel's coefficient——A Case Study of Rural Areas in Hebei Province

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Asian Agricultural Research 2011年第4期3卷 24-29页

作者： HAO Jun1,LIU Jie2 1.Shijiazhuang Postal Vocational and Technical College,Shijiazhuang 050021,China 2.Business School,Hebei Normal University,Shijiazhuang 050024,China Shijiazhuang Postal Vocational and Technical College Business School Hebei Normal University

On the basis of introducing relevant theories of Engel's coefficient,this paper analyzes the limitation of these theories in practical application currently in China,for example,continuing to use original theory,not in line with reality of China;comparison invalidity in length and breadth,is not conducive to relevant analysis;culling out the special factors easily causes distortion of conclusion.Taking rural areas in Hebei Province as an example,this paper analyzes the limitation of Engel's coefficient in analyzing the gap of rural economy:in terms of region horizontally,Engel's coefficient neglects the difference of consumption structure among regions,and difference of economic stages among regions;in terms of time vertically,Engel's coefficient neglects the periodic change of consumption structure and the ratio change of different families in different periods.According to the reality of China's rural areas,the correction model of Engel's coefficient is established as follows.Firstly,Engel's coefficient=Percentage of expenditure variation(food+ education+ medical service) /Percentage of total expenditure variation;Engel's coefficient=Percentage of expenditure variation(food+ education+ medical service) /Percentage of income variation.Secondly,Engel's coefficient=Percentage of expenditure variation of food/Percentage of variation of(total expenditure educational expenditure-medical expenditure.Thirdly,Engel's coefficient=Percentage of expenditure variation of food/Percentage of total expenditure variation.

关键词： Engel’s coefficient Difference of consumption stru

A General Calculating Method of Rotor’s Torsional Stiffness Based on Stiffness Influence coefficient

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Engineering（科研） 2010年第9期2卷 698-704页

作者： Danmei Xie Wangfan Li Ling Yang Yong Qian Xianbo Zhao Zhigang Gao School of Power and Mechanical Engineering Wuhan University Dongfang Turbine Co. Ltd

In order to develop a general calculating rotor’s torsional stiffness based on stiffness influence coefficient for different rotor assembling, the calculation method of the torsional stiffness influence coefficient of equal thickness disc is researched in this paper at first. Then the torsional stiffness influence coefficient λ of equal thickness disc is fit to a binary curved face and a calculation equation is obtained based on a large quantity of calculating data, which lays the foundation for research on a general calculating method of rotor torsional stiffness. Thirdly a simplified calculation method for equivalent stiffness diameter of stepped equal thickness disc and cone disc in the steam turbine generators is suggested. Finally a general calculating program for calculating rotor’s torsional vibration features is developed, and the torsional vibration features of a verity of steam turbine rotors are calculated for verification. The calculating results show that stiffness influence coefficient λ of equal-thickness disc depends on parameters of B and H, as well as the stiffness influence coefficient λ;and discs with complex structure can be simplified to equal-thickness discs with little error by using the method suggested in this paper;error can be controlled within 1% when equivalent diameter of stiffness is calculated by this method.

关键词： Rotor Disc General Calculating Method Torsional Stiffness Stiffness Influence coefficient

The ultrasonic-enhanced factor of mass-transfer coefficient in the supercritical carbon dioxide extraction

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Science China(Physics,Mechanics & Astronomy) 2008年第10期51卷 1496-1504页

作者： LUO BenYi LU YiGang School of Physics South China University of TechnologyGuangzhou 510640China

Based on several hypotheses about the process of supercritical carbon dioxide extraction, the onflow around the solute granule is figured out by the Navier-Stocks equation. In combination with the Higbie’s solute infiltration model, the link be-tween the mass-transfer coefficient and the velocity of flow is found. The mass-transfer coefficient with the ultrasonical effect is compared with that without the ultrasonical effect, and then a new parameter named the ultrasonic-enhanced fac-tor of mass-transfer coefficient is brought forward, which describes the mathe-matical model of the supercritical carbon dioxide extraction process enhanced by ultrasonic. The model gives out the relationships among the ultrasonical power, the ultrasonical frequency, the radius of solute granule and the ultrasonic-enhanced factor of mass-transfer coefficient. The results calculated by this model fit well with the experimental data, including the extraction of Coix Lacryma-jobi Seed Oil (CLSO) and Coix Lacryma-jobi Seed Ester (CLSE) from coix seeds and the extrac-tion of Eicosapentaenoic Acid (EPA) and Docosahexaenoic Acid (DHA) from the alga by means of the ultrasonic-enhanced supercritical carbon dioxide extraction (USFE) and the supercritical carbon dioxide extraction (SFE) respectively. This proves the rationality of the ultrasonic-enhanced factor model. The model provides a theoretical basis for the application of ultrasonic-enhanced supercritical fluid extraction technique.

关键词： ultrasonic enhance mass-transfer coefficient supercritical fluid extraction

Algorithm Derivation of Winter Facies Wind Protection of Shelterbelts Structural Parameters and Wind Permeability coefficient

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Chinese Forestry Science and Technology 2012年第3期11卷 89-90页

作者： Wang Zhigang Ren Yu Experimental Center for Desert Forestry Chinese Academy of Forestry

To solve the problem in the absence of permeability algorithm in China’s forestry industry standard "Technical Specification for Oasis Shelter Belt Construction(LY/T 1682—2006)",by defining and calculating the forest structural parameters-porosityβ,stumpage surface porosity S",stumpage volume porosity V’,aboveground surface area density C,aboveground bulk density W,the relations among these structural parameters and their relations with wind permeability coefficientα,shelterbelt width D and mean diameter of branch d were calculated,which is expressed as:W=V’/D=dC/4 =dS’/4D=-πdlnβ/4D = -0.1πZdlnα/D.It is proofed that the main structural parameters have homogeneity and different structural parameters are of inheritance and consistency on the nature,there is no exclusivity in the strict sense,and is convertible under certain conditions,which is convenient for evaluating the wind-resistance effect of shelterbelt. A set of computational formulas for wind effect evaluation of farmland shelterbelt in dry and sandy area in northern China is derived.

关键词： farmland shelterbelt porosity stumpage porosity surface density bulk density wind permeability coefficient

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变系数三阶周期边值问题的正解(英文)

吉首大学学报（自然科学版） 2010年第6期31卷 9-13页

作者：姚庆六南京财经大学应用数学系江苏南京210003

研究了变系数非线性三阶周期边值问题的正解.非线性项可以关于空间变元奇异.利用适当的变换此问题被转换为一个Hammerstein积分方程,利用锥上的Guo-Krasno-selski不动点定理获得了1～2个正解的存在性.

关键词：变系数三阶周期边值问题正解 Variable coefficient Boundary Value Problems Solutions fixed point theorem on cone Hammerstein boundary value problem variable coefficient positive solutions transformation nonlinear term 非线性项不动点定理 existence 积分方程存在性 making 转换

Adhesion coefficient of automobile tire and road surface

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Journal of Central South University 2008年第S1期15卷 210-214页

作者：刘长生 School of Traffic and Tansportation Engineering Central South University of Forestry and Technology

The adhesion coefficient of automobile tire and road surface was analyzed and the formula about it was derived.Some suggestions about highway construction,driving safety of the drivers and the judgment of the traffic accidents were presented.The results show that the adhesion coefficient is a function with the extreme value.If there is atmospheric pressure in the tire,the load of the vehicle and the degree of the coarse on the road surface is not selected properly,it will reach the least and affect the safety of the running automobile.

关键词： constitutive model microstructure mechanics element connecting type adhesion coefficient pavement profile tribology analysis calculation comprehension evaluation

B-spline estimation for varying coefficient regression with spatial data

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Science China Mathematics 2009年第11期52卷 2321-2340页

作者： TANG QingGuo CHENG LongSheng School of Economics and Management Nanjing University of Science and TechnologyNanjing 210094China Institute of Sciences PLA University of Science and TechnologyNanjing 210007China

This paper considers a nonparametric varying coefficient regression with spatial data. A global smoothing procedure is developed by using B-spline function approximations for estimating the coefficient functions. Under mild regularity assumptions,the global convergence rates of the B-spline estimators of the unknown coefficient functions are established. Asymptotic results show that our B-spline estimators achieve the optimal convergence rate. The asymptotic distributions of the B-spline estimators of the unknown coefficient functions are also derived. A procedure for selecting smoothing parameters is given. Finite sample properties of our procedures are studied through Monte Carlo simulations. Application of the proposed method is demonstrated by examining voting behaviors across US counties in the 1980 presidential election.

关键词： spatial data varying coefficient regression B-spline estimators convergence rate asymptotic distribution