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The Superiorities of Bayes Linear Unbiased Estimator in Multivariate Linear Models

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Acta Mathematicae Applicatae Sinica 2012年第2期28卷 383-394页

作者： Wei-ping ZHANG lai-sheng WEI Yu CHEN Department of Statistics and Finance University of Science and Technology of China Hefei 230026 China

In this article, the Bayes linear unbiased estimator （BALUE） of parameters is derived for the multivariate linear models. The superiorities of the BALUE over the least square estimator （LSE） is studied in terms of... 详细信息

关键词： multivariate linear models Bayes linear unbiased estimator least square estimator mean squareerror matrix criterion Bayesian Pitman closeness criterion

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杨辉三角的又一性质及MATLAB计算

实验科学与技术 2011年第6期9卷 189-192页

作者：张悦赖生建王晓琼张瑾电子科技大学物理电子学院成都610054 电子科技大学电子工程学院成都610054

文中研究了杨辉三角的又一性质以及采用MATLAB进行编程的计算技巧。从杨辉三角与数字11的密切关系,提出了杨辉三角的又一性质,并总结又一性质的规律和证明了该性质的正确性。在编程计算实验中,利用MATLAB在矩阵计算方面的一些特点,发现... 详细信息

文中研究了杨辉三角的又一性质以及采用MATLAB进行编程的计算技巧。从杨辉三角与数字11的密切关系,提出了杨辉三角的又一性质,并总结又一性质的规律和证明了该性质的正确性。在编程计算实验中,利用MATLAB在矩阵计算方面的一些特点,发现将又一性质中的辗转相加法可以用非常巧妙的MATLAB编程实现方式,这与采用C语言的计算编程相比,高效简洁得多,并能直观展现又一性质中的辗转相加法。

关键词：杨辉三角又一性质辗转相加法 MATLAB

Melting and floating processes of inorganic materials in molten steel:Visualization physical simulation and mathematical modelling

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China Foundry 2023年第2期20卷 89-98页

作者： Jin-hu lai sheng Yu Yang-jian Xu Dan-qing Jiang San-san Shuai Jiang wang Zhong-ming Ren State Key Laboratory of Advanced Special Steel School of Materials Science and EngineeringShanghai UniversityShanghai 200444China Shaoxing Institute of Technology Shanghai UniversityShaoxing 312000ZhejiangChina

It has been demonstrated that heat absorption method by using the inorganic material rod to cool the molten steel can significantly reduce the macrosegregation level of the large steel ***,owing to the opacity of the molten steel,the physical mechanism of the heat absorption method is not *** this work,a transparent hydraulic physical model with water and paraffin wax was built to simulate the melting and floating processes of inorganic materials in the molten steel.A mathematical simulation was also carried out to analyze the connection between the actual ingot and the physical *** show that it is feasible to simulate the molten steel and inorganic materials with water and paraffin *** the help of the physical model,the process of the melting of paraffin wax and its floating to the surface of water were clearly observed,during which the temperature of water at some characteristic positions in the mold was *** visualization findings demonstrate that the melting and floating processes of paraffin wax can help to bring the heat from the center of the mold to the top surface more quickly,which reduces the superheat and significantly accelerates the cooling rate of *** experimental results show that for the water with a certain superheat,the use of a larger mass of paraffin wax can accelerate the cooling of the water,but there is a risk of incomplete melting of the paraffin wax.A higher superheat of water will lead to a quicker melting rate for a given mass of paraffin wax,while a lower superheat leads to the incomplete melting of paraffin wax as well.

关键词： water and paraffin wax heat absorption method physical simulation superheat large steel ingot

EXPERIMENTS ON HYDRODYNAMIC INTERACTION BETWEEN 3-D OVAL AND WALL

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Journal of Hydrodynamics 2007年第1期19卷 121-126页

作者： SUN Ke sheng Qi-hu ZHANG Liang LI Feng-lai College of Shipbuilding Engineering Harbin Engineering University Harbin 150001 China

The boundary hydrodynamic interaction of a 3-D oval body was experimentally surveyed for different cases. The regression method was employed to fred the experimental formulae of hydrodynamic coefficients relating to the attack angle, clearance to wall, and moving speed. The mechanism of interaction was discussed. The experimental results show that there exists a lifting effect, similar to wings in flow. The lifting effect is remarkable. The boundary hydrodynamic interaction of the small aspect ratio model is almost linearly dependent on the attack angle, but the effect of the moving speed of the body on the hydrodynamic coefficients is very small. The effect of clearance is related to the geometric shape. The boundary hydrodynamic interaction always enhances the lifting effect if the clearance is small.

关键词： hydrodynamic coefficient model experiment,boundary interaction oval

Influences of aerodynamic loads on hunting stability of high-speed railway vehicles and parameter studies

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Acta Mechanica Sinica 2014年第6期30卷 889-900页

作者： Xiao-Hui Zeng Han Wu Jiang lai Hong-Zhi sheng Key Laboratory for Mechanics in Fluid Solid Coupling Systems Institute of Mechanics Chinese Academy of Sciences

The influences of steady aerodynamic loads on hunting stability of high-speed railway vehicles were investigated in this study.A mechanism is suggested to explain the change of hunting behavior due to actions of aerodynamic loads：the aerodynamic loads can change the position of vehicle system（consequently the contact relations）,the wheel/rail normal contact forces,the gravitational restoring forces/moments and the creep forces/moments.A mathematical model for hunting stability incorporating such influences was developed.A computer program capable of incorporating the effects of aerodynamic loads based on the model was written,and the critical speeds were calculated using this *** dependences of linear and nonlinear critical speeds on suspension parameters considering aerodynamic loads were analyzed by using the orthogonal test method,the results were also compared with the situations without aerodynamic *** is shown that the most dominant factors a ff ecting linear and nonlinear critical speeds are different whether the aerodynamic loads considered or *** damping of yaw damper is the most dominant influencing factor for linear critical speeds,while the damping of lateral damper is most dominant for nonlinear *** the influences of aerodynamic loads are considered,the linear critical speeds decrease with the rise of cross wind velocity,whereas it is not the case for the nonlinear critical *** variation trends of critical speeds with suspension parameters can be significantly changed by aerodynamic *** actions of aerodynamic loads and suspension parameters also a ff ect the critical *** effects of such joint action are more obvious for nonlinear critical speeds.

关键词： Hunting stability Linear critical speed Nonlinear critical speed Aerodynamic loads Suspension parameters Orthogonal experimental design

Advanced non-precious electrocatalyst of the mixed valence CoO_x nanocrystals supported on N-doped carbon nanocages for oxygen reduction

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Science China Chemistry 2015年第1期58卷 180-186页

作者： sheng Chen Liwei wang Qiang Wu Xiang Li Yu Zhao Hongwei lai Lijun Yang Tao Sun Yi Li Xizhang wang Zheng Hu Key Laboratory of Mesoscopic Chemistry of Ministry of Education Jiangsu Provincial Lab for Nanotechnology School of Chemistry and Chemical Engineering Nanjing University

Taking advantage of the nitrogen(N)-participation and large surface area of N-doped carbon nanocages(NCNCs),the Co Ox nanocrystals are conveniently immobilized onto the NCNCs with high *** Co Ox/NCNCs hybrid exists in the mixed valence with predominant Co O over Co3O4 and demonstrates superb oxygen reduction reaction activity and stability remaining^94%current density even after operation over 100 *** results suggest a promising strategy to develop advanced electrocatalysts with the novel NCNCs or even beyond.

关键词： cobalt oxide nanocrystals fuel cells non-precious electrocatalysts nitrogen doped carbon nanocages oxygen reductionreaction

Effect of targeted magnetic nanoparticles containing 5-FU on expression of bcl-2, bax and caspase 3 in nude mice with transplanted human liver cancer

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World Journal of Gastroenterology 2007年第23期13卷 3171-3175页

作者： Jian-Ming wang Bao-lai Xiao Jian-Wei Zheng Hai-Bing Chen sheng-Quan Zou Department of General Surgery of Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430 030 Hubei Province China Department of Material Wuhan University of Technology Wuhan 430030 Hubei Province China

AIM: To investigate the anti-tumor effect and mechanisms of magnetic nanoparticles targeting hepatocellular carcinoma. METHODS: Human hepatocellular carcinoma was induced in nude mice, and the mice were randomly divided into group A receiving normal saline, group B receiving magnetic nanoparticles containing 5-fluorouracil (5-FU), group C receiving 5-FU, and group D receiving magnetic nanoparticles containing 5-FU with a magnetic field built in tumor tissues. The tumor volume was measured on the day before treatment and 1, 4, 7, 10 and 13 d after treatment. Tumor tissues were isolated for examination of the expression of bcl-2, bax and caspase 3 by immunohistochemical method, reverse transcription polymerase chain reaction and Western blotting. RESULTS: The tumor volume was markedly lower in groups C and D than in groups A and B (group C or D vs group A or B, P < 0.01). The volume was markedly lower in group D than in group C (P < 0.05). The expression of protein and mRNA of bcl-2 was markedly lower in groups C and D than in groups A and B (group C or D vs group A or B, P < 0.01), and was markedly lower in group D than in group C (P < 0.01). The expression of bax and caspase 3 in groups C and D was signif icantly increased, compared with that in groups A and B (P < 0.01). CONCLUSION: The targeted magnetic nanoparticles containing 5-FU can improve the chemotherapeutic effect of 5-FU against hepatocellular carcinoma by decreasing the expression of bcl-2 gene, and increasing the expression of bax and caspase 3 genes.

关键词： Hepatocellular carcinoma Magnetic nanoparticles Fluorouracil Bcl-2 Bax Caspase 3

Synthesis and biological evaluation of novel thalidomide analogues as potential anticancer drugs

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Chinese Chemical Letters 2008年第8期19卷 928-930页

作者： Tao wang Yi Hua Zhang Shan Yu Hui Ji Yi sheng lai Si Xun Peng a Center of Drug Discovery China Pharmaceutical University Nanjing 210009 China Department of Pharmacology China Pharmaceutical University Nanjing 210009 China

In search of novel anticancer agents, a series of thalidomide analogs （6a-j） were designed and synthesized. Cytotoxicity of these compounds against human hepatoma cells （HepG2） was evaluated by MTT method. Compoun... 详细信息

关键词： Thalidomide 1,3,4-Thiadiazole Anti-tumor activity HepG2

Identification of proteins of human colorectal carcinoma cell line SW480 by two-dimensional electrophoresis and MALDI-TOF mass spectrometry

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World Journal of Gastroenterology 2005年第30期11卷 4679-4684页

作者： Ying-Tao Zhang Yi-Ping Geng Le Zhou Bao-Chang lai Lv-sheng Si Yi-Li wang The-Key Laboratory of Biomedical Information Engineering of Education Ministry Institute of Cancer Research School of Life Science and Technology Xi'an Jiaotong University Xi'an 710061 Shaanxi Province China Department of Gastroenterology First Hospital Xi'an Jiaotong University Xi'an 710061 Shaanxi Province China

AIM： To conduct bhe proteomic analysis of human colorectal carcinoma cell line, SW480 by using two-dimensional electrophoresis （2-DE） and matrix-assisted laser desorption /ionization-time of flight mass spectrometry （MALDITOFMS）. METHODS： The total proteins of human colorectal carcinoma cell line, SW480 were separated with 2-DE by using immobilized pH gradient strips and visualized by staining with silver nitrate. The gel images were acquired by scanner and 2-DE analysis software, Image Master 2D Elite. Nineteen distinct protein spots were excised from gel randomly and digested in gel by TPCK-trypsin. Mass analysis of the byptic digest peptides mixture was performed by using MALDI-TOF MS. Peptide mass fingerprints （PMFs） obtained by the MALDI-TOF analysis were used to search NCBI, SWISS-PROT and MSDB databases by using Mascot software. RESULTS： PMF maps of all spots were obtained by MALDI-TOF MS and thirteen proteins were preliminarily identified. CONCLUSION： The methods of analysis and identification of protein spots of tumor cells in 2-DE gel with silver staining by MALDI-TOF MS derived PMF have been established. Protein expression profile of SW480 has been obtained. It is demonstrated that a combination of proteomics and cell culture is a useful approach to comprehend the process of colon carcinogenesis.

关键词： Colorectal carcinoma SW480 cell line Twodimensional electrophoresis MALDI-TOF MS Peptide mass fingerprinting