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Integrating Factors and Conservation Theorems of Lagrangian Equations for Nonconservative Mechanical System in Generalized Classical Mechanics

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Communications in Theoretical Physics 2006年第1X期46卷 43-45页

作者： QIAO Yong-Fen zhao Shu-Hong Department of Mechanical Engineering and Automation Zhejiang Science and Technology University Hangzhou 310018 China Engineering College of Northeast Agricultural University Harbin 150030 China

The conservation theorems of the generalized Lagrangian equations for nonconservative mechanical system are studied by using method of integrating factors. Firstly, the differential equations of motion of system are given, and the definition of integrating factors is given. Next, the necessary conditions for the existence of the conserved quantity are studied in detail. Finally, the conservation theorem and its inverse for the system are established, and an example is given to illustrate the application of the result.

关键词： generalized nonconservative system Lagrangian equation conservation theorem integrating factor

A smart cluster paradigm based Mo-containing polyoxometalate as a new therapeutic strategy for tumor-specific photothermal therapy

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Science Bulletin 2018年第14期63卷 877-878页

作者： Yuan Yong Shengtao Yang Zhigang zhao College of Chemistry and Environment Protection Engineering. Southwest Minzu University. Chengdu 610041 China

A desirable near-infrared(NIR)photothermal agent based on Mo-based polyoxometalate cluster with self-adaptive electronic structure for tumor acidity/reducibility-specific therapy was reported in a paper on Journal of the American Chemical Society[1].This‘‘small-big"cluster paradigm displayed the capacity of self-assemble to big molecules under activation both the

关键词：治疗学肿瘤瞬间簇电子结构微型环境红外线代理人

Feedforward and feedback optimal control for linear time-varying systems with persistent disturbances

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Journal of Systems Engineering and Electronics 2006年第2期17卷 350-354页

作者： Tang Gongyou zhao Yandong Zhang Baolin Coll. of Information Science and Engineering Ocean Univ. of China Qingdao 266071 P. R. China

The optimal control problem for linear time-varying systems affected by external persistent disturbances with known dynamic characteristics but unknown initial conditions is consider and a design procedure of a feedforward and feedbaek optimal controller is presented. The condition of existence and uniqueness of the control law is given. The disturbanee observer is proposed to make the feedforward control law realizable physically. Simulation results demonstrate that the feedforward and feedbaek optimal control law is more effective and robust than the elassical state feedbaek control law with respect to external disturbanees.

关键词： time-varying systems persistent disturbances optimal control feedforward control disturbance observer.

Variation and heritability of morphological and physiological traits among Leymus chinensis genotypes under different environmental conditions

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Journal of Arid Land 2019年第1期11卷 66-74页

作者： YANG Xue LI Junpeng zhao Tingting MO Lidong ZHANG Jianli REN Huiqin zhao Nianxi GAO Yubao Department of Plant Biology and Ecology College of Life Science Nankai University

Intraspecific trait variation and heritability in different environmental conditions not only suggest a potential for an evolutionary response but also have important ecological consequences at the population, community, and ecosystem levels. However, the contribution of quantitative trait variation within a grassland species to evolutionary responses or ecological consequences is seldom documented. Leymus chinensis is an important dominant species in semi-arid grasslands of China, which has seriously suffered from drought and high temperature stresses in recent decades. In the present study, we measured variation and heritability of 10 quantitative traits, namely the number of tillers, maximum shoot height, number of rhizomes, maximum rhizome length, rhizome mass, aboveground mass, root mass, maximum net photosynthetic rate(Pmax), specific leaf area(SLA), and leaf length to leaf width ratio(LL/LW), for 10 genotypes of L. chinensis under one non-stress(Ck) condition and three environmental stress conditions(i.e., drought(Dr), high temperature(Ht), and both drought and high temperature(DrHt)). Result indicated that(1) the interaction of genotype and environmental condition(G×E) was significant for 6 traits but not significant for the other 4 traits as shown by two-way analysis of variance(ANOVA), suggesting that different selection forces were placed for different traits on the factors dominating phenotypic responses to different environmental conditions. Moreover, these significant G×E effects on traits indicated significantly different phenotypic adaptive responses among L. chinensis genotypes to different environmental conditions. Additionally, individuals could be grouped according to environmental condition rather than genotype as shown by canonical discriminant analysis, indicating that environmental condition played a more important role in affecting phenotypic variation than genotype;(2) by one-way ANOVA, significant differences among L. chinensis genotypes w

关键词： Leymus chinensis genotype quantitative trait variation heritability drought high temperature

Effect of arginine on stability of GST-ZNF191(243-368)

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Chinese Chemical Letters 2007年第3期18卷 355-356页

作者： Dong Xin zhao Zhong Xian Huang Chemical Biology Lab Department of Chemistry Fudan University Shanghai 200433 China

For better understanding the chemical or biological information of ZNF191 （243-368）, we expressed the fusion protein of GST and ZNF191 （243-368）, and used it to obtain the binding DNA sequence of this zinc finger protein. But in the process of expression and purification, we found this fusion protein slowly degradated. For resolving this problem, we simultaneously added charged amino acids L-Arg and L-Glu to the solution of fusion protein, and demonstrated that this method can dramatically increase the stability of this fusion protein. This method can make the fusion protein suitable for the continuous works, especially for situations where high protein concentration and long-term stability without precipitate and degradation of protein are required.

关键词： ZNF191(243-368) GST Stability L-Arg L-Glu

A New Method for the Synthesis of C/D Ring Synthon of Vitamin D

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Chinese Chemical Letters 1998年第3期9卷 259-260页

作者： Gao, LJ zhao, TZ Han, GD Henan Acad Sci Inst Chem Zhengzhou 450003 Peoples R China Chinese Acad Med Sci Inst Mat Med Peking Union Med Coll Beijing 100050 Peoples R China

A C/D ring synthon of vitamin D is readily obtained from cholesteryl acetate via oxidation, elimination of acetoxy group and Norrish type II photochemical reaction.

关键词： C/D ring synthon vitamin D cholesteryl acetate photochemical degradation

Shifting the Education Paradigm:Why International Borrowing Is No Longer Sufficient for Improving Education in China

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ECNU Review of Education 2018年第1期1卷 76-106页

作者： Yong zhao East China Normal University&University of Kansas

Purpose-The purpose of this article is to examine the consequences of mutual borrowing of educational policies and practices between the East and the West and implications for Chinese ***/Approach/Methods-This paper draws upon a wide variety of historical,cultural,and international assessment ***-The analyses found that the mutual borrowing is unlikely to improve education to the extent that the future world ***/Value-Thus,the article concludes that instead of wasting resources and time on learning from each other’s past,education systems around the world should work on inventing a new paradigm of *** is in a unique position to work on the new paradigm.

关键词： Education reform technology comparative education East Asian education Western education future of education

Ni_(3)S_(2) nanocrystals in-situ grown on Ni foam as highly efficient electrocatalysts for alkaline hydrogen evolution

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Rare Metals 2023年第10期42卷 3420-3429页

作者： Rui Sun Zhan-Hua Su Zhi-Feng zhao Mei-Qi Yang Tian-Sheng Li Jing-Xiang zhao Yong-Chen Shang College of Chemistry Guangdong University of Petrochemical TechnologyMaoming525000China College of Chemistry and Chemical Engineering Harbin Normal UniversityHarbin150025China

The exploitation of cost-efficient electrocatalysts is critical to develop the hydrogen evolution reaction(HER) for hydrogen ***,Ni_(3)S_(2)/NF-x h(x=12,16 and 20,reaction time) nanocrystals in-situ grown on Ni foam(NF) were prepared via a facile hydrothermal *** results demonstrate that the reaction time plays key roles in the morphology,the hydrogen evolution performance of the samples,and the hydrogen brittleness of NF ***,the Ni_(3)S_(2)/NF-16 h displays outstanding catalytic activity for HER in alkaline solution and avoids the hydrogen brittleness of the NF skeletons *** afford a catalytic current of20 mA·cm^(-2),Ni_(3)S_(2)/NF-16 h presents ultra-low overpotential of 48 mV for hydrogen evolution and sufficient stability for 40 ***,the density functional theory(DFT) calculations revealed that the excellent electrocatalytic HER activity of Ni_(3)S_(2) could be attributed to its exposed(015) plane,which exhibited good capability for water adsorption and dissociation in an alkaline electrolyte,leading to the optimal free energy for H^(*) *** present work offers a novel strategy to design,synthesize and develop highly efficient electrocatalysts for HER.

关键词： Ni_(3)S_(2) Electrocatalysts Hydrogen evolution reaction Density functional theory calculations

Dielectric Behavior of Middle Phase Microemulsion

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Chinese Chemical Letters 2000年第8期11卷 739-742页

作者： Lei, JP Li, Y zhao, KS S China Normal Univ Dept Chem Guangzhou 510631 Peoples R China

Dielectric measurements were performed on middle phase microemulsions composed of sodium dodecylsulfate(SDS), cetyltrimethylammonium bromide(CTAB), n-butanol, n-heptane and brine. Distinct and unique dielectric behavior, with characteristic frequency dependence regularity on the salinity of the microemulsions, was observed in the low-frequency range from 10-10(3)Hz. It can be considered to be an interfacial polarization mechanism.

关键词： middle phase microemulsions dielectric spectroscopy relaxation time