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Journal of Wuhan University of Technology(Materials Science) 2006年第4期21卷 173-176页

作者：杨平 research center of Micro-Nano Science and Technology Jiangsu University Zhenjiang 212013ChinaResearch Center of Advanced Design & Manufacturing Guilin Institute of Electronic Technology Guilin 541004 China

The aim of this article was to provide a systematic method to perform molecular dynamics simulotion or evaluation for nano-scale interfacial friction behavior between two kinds of materials in MEMS design. Friction is an important factor affecting the performance and reliability of MEMS. The model of the nano-scale interracial friction behavior between two kinds of materials was presented based on the Newton＇ s equations of motion. The Morse potential function was selected for the model. The improved Verlet algorithm was employed to resolve the model, the atom trajectories and the law of the interfacial friction behavior. Comparisons with experimental data in other paper confirm the validity of the model. Using the model it is possible to simulate or evaluate the importance of different factors for designing of the nano-scale interfacial friction behavior between two kinds of materials in MEMS.

关键词： molecular dynamics simulation interfacial friction nano-scale friction MEMS

Quasi-static Analysis of Thrust-loaded Angular Contact Ball Bearings part Ⅱ:results and Discussion

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Chinese Journal of Mechanical Engineering 2012年第1期25卷 81-87页

作者： CHEN Wenhua1,2,MA Zikui1,GAO Liang1,LI Xinglin3,and pAN Jun2 1 Institute of Mechanical design,Zhejiang University,Hangzhou 310027,china 2 Institute of Mechanical design and Manufacturing,Zhejiang Sci-Tech University,Hangzhou 310018,china 3 State Testing Laboratory of Hangzhou Bearing Test & research center,Hangzhou 310022,china Institute of Mechanical design Zhejiang University Hangzhou China Institute of Mechanical design and Manufacturing Zhejiang Sci-Tech University Hangzhou China State Testing Laboratory of Hangzhou Bearing Test & research center Hangzhou China

Ball bearings are widely employed mechanical components characterized by high precision and quality,and usually play important roles in various rotary machines and *** advanced applications require a deep understanding of their various kinematic and tribological characteristics that are essential to predict the fatigue endurance,relieve the vibration and minimize the power dissipation of ball bearings in particular *** angular contact ball bearing under a specified operating condition is simulated with the quasi-static/creepage analytical model proposed in the preceding *** results demonstrate that the ball bearing is a statically determinate *** the balls spin on both inner and outer races means the ball is controlled by neither the inner nor the outer *** friction between the ball and raceway renders the inner and outer contact angles *** larger the coefficient of friction is,the larger the angle *** tangential traction perpendicular to the rolling direction due to the spin induces a gyro-like rotation of the ball with respect to the raceway even if no inertial effects are *** tangential elastic compliance of contacting surfaces gives rise to locked areas within the contact patch and transforms the sliding lines from circles into *** differential slip due to the close conformity of the ball and raceway makes the sliding and traction distributions asymmetric,which will influence the location of the spinning center of the ball with respect to the *** quasi-static/creepage model can be used to reveal the operating behaviors of ball bearings running under steady conditions and to optimize the design of ball bearings for specific applications.

关键词： ball bearing quasi-static creepage differential slip tangential elastic compliance

A discussion on typhoon occurred in the Haikou Bay and impact mechanism on seawater quality

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Acta Oceanologica Sinica 2001年第3期20卷 355-362页

作者： Chen Chunhua, Li Qiaoxiang 1.Marine Exploitation plan & design research Institute of Hainan province, Haikou 570203, china 2.Marine Monitoring center of Hainan province, Haikou 570011, china Marine Exploitation plan/design res. Institute of Hainan Province Haikou 570203 China Marine Monitoring Ctr. Hainan prov. Haikou 570011 China

Water quality parameters such as pH, DO, COD, pQ4 - p, SiO3 - Si, NO2 - N, NO3 -N in the Haikou Bay were monitored respectively before and after Typhoon 9618 occurring on Sep. 18, 1996. Based on the statistics of typhoon in the Haikou Bay and numerical calculation of stormy current, the mechanism of water quality variation caused by typhoon is discussed. The typhoon impact on the Haikou Bay usually appears between July and November, most usually between August and October. The monitoring results before a typhoon were different from that. The stormy wave and windstorm cur-rent stir up the sediment in near-shore bottom and make the bottom water mix with the surface water strongly, specially windstorm current with strong velocity at the head of the bay stirs up higher pollutants sediment near sea area of sewage outfall, and heavy rain with typhoon carries the pollutants from land through the Nandu river to the Haikou Bay, so the contents of COD, pO4 - p, NO4 - N, NO3 ~N, SiO3 after a typhoon are higher than those before. Windstorm current is violent, which makes offshore high DO water exchange more frequently with inner bay water and oxygen in the air dissolves in sea water faster, so DO content after typhoon is higher than that before typhoon. This strong action of water exchange also causes lower pH change before and after the typhoon.

关键词： The Haikou Bay typhoon seawater quality impact mechanism

3D-QSAr study of 20(S)-camptothecin analogs

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Acta pharmacologica Sinica 2007年第2期28卷 307-314页

作者： Ai-jun LU~(1,2) Zhen-shan ZHANG~2 Ming-yue ZHENG~2 Han-jun ZOU~2 Xiao-min LUO~2 Hua-liang JIANG~(2,3,4)1 Jiangsu Simcere pharmaceutical research Company Ltd,Nanjing 210042,china 2 Drug Discovery and design center,State Key Lab of Drug research,Shanghai Institute of Materia Medica,Chinese Academy of Sciences,Shanghai 201203,china 3 School of pharmacy,East china University of Science and Technology,Shanghai 200237,china Jiangsu Simcere pharmaceutical research Company Ltd Nanjing China Drug Discovery and design center State Key Lab of Drug Research Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai China School of pharmacy East China University of Science and Technology Shanghai China

Aim:To build up a quantitative structure-activity relationship（QSAr）model of20（S）-camptothecin（CpT）analogs for the prediction of the activity of new CpTanalogs for drug ***:A training set of 43 structurally diverse CpTanalogs which were inhibitors of topoisomerase I were used to construct a quan-titative structure-activity relationship model with a comparative molecular fieldanalysis（CoMFA）.The QSAr model was optimized using partial least squares（pLS）analysis.A test set of 10 compounds was evaluated using the ***:The CoMFA model was constructed successfully,and a good cross-validated correlation was obtained in which q2was ***,the analysis ofthe non-cross-validated pLS model in which r2was 0.935 was built and permitteddemonstrations of high predictability for the activities of the 10 CpT analogs inthe test set selected in ***:The CoMFA model indicated thatbulky negative-charged group at position 9,10 and 11 of CpT would increaseactivity,but excessively increasing bulky group at position 10 is adverse to inhibi-tory activity;substituents that occupy position 7 with the bulky positive groupwill enhance the inhibitive *** model can be used to design new CpTanalogs and understand the mechanism of action.

关键词： comparative molecular field analysis(CoMFA) camptothecin(CpT) topoisomerase I(Top I)

Scheduling of Development projects with Uncertain Iterations

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Journal of Systems Engineering and Electronics 2001年第2期12卷 82-86页

作者： Yan Jihong & Wu Cheng National CIMS Engineering research center, Tsinghua University, Beijing 100084, p r. china National CIMS Engineering research center Tsinghua University Beijing 100084 P. R. China

This paper studies the scheduling of design projects in concurrent development process with uncertain number of feedback revisions. An optimization based methodology that combines heuristic algorithm, artificial intelligence (fuzzy, genetic algorithm) and scheduling theory is developed. In the algorithm, weighting values of some key factors are defined by genetic algorithm. In addition, fuzzy logic is used to decide the ability coefficients of different roles taken by designers. Moreover, the process of pre-release and feedback revision is realized. Simulation example is a fraction of practical development project, and satisfied results are obtained.

关键词： Concurrent engineering product development process Optimization scheduling.

Geotechnical properties of oceanic sediments in polymetallic nodules belts

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Acta Oceanologica Sinica 2000年第2期19卷 57-67页

作者： Song Lianqing1 (1. center for Ocean Engineering Survey, design and research, State Oceanic Administration,Hangzhou 310012, china) Ctr. for Ocean Engineering Survey State Oceanic Administration Hangzhou 310012 China

Geotechnical data obtained from the polymetallic nodules investigation in 1994, in combi nation with the historical data concerned, are analyses comprehensively to study sediment types, geotechnical properties, soil strength and so on, in order to provide bases for design and construction of engineering facilities and the equipments raquired for the polymetallic nodules mining in the future.

关键词： polymetallic nodules geotechnical properties of sediments soil strength

Explanation of the mechanism of carcinogenesis and syntheses of anticancer agents with high selectivity

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Science china Chemistry 2006年第1期49卷 44-62页

作者： DAI Qianhuan1,2 1. center of Chemistry and Bioengineering of Cancer research, Beijing polytechnic University (Now known as Beijing Univer-sity of Technology), Beijing 100022, china 2. center of Environmental Sciences, peking University, Beijing 100871, china center of Chemistry and Bioengineering of Cancer research Beijing Polytechnic University Beijing China center of Environmental Sciences Peking University Beijing China

In 1979, the mechanism of chemical carcinogenesis, a challenging anddifficult scientific problem pending for a number of years, was explained by Dai Qianhuan. Themechanism named di-region theory predicted that a carcinogen always metabolizes to form a specialbi-functional alky-lating agent. This agent induces cross-linkages between the complementary basepairs in DMA and switches on initial mutageneses in genomes including point and frameshiftmutations. This, in turn, induces further deep mutageneses including the production of variouschimeric chromosomes, deletions and other aberrations found in genomes. In the end this initiatescarcinogenesis of the whole cell through the reverse transcription mechanism after a lengthyincubation period. recently, this laboratory has verified that physical carcinogenesis, includingthe oncogenesis induced by radiation and asbestos as well as the carcinogenesis induced byendogenous factors such as estrogen or diethyl-stilbestrol switch on carcinogenesis by inducing theformation of cross-linkages between the complementary base pairs in DNA. Di-region theory has nowbeen supported by many experimental observations such as mutational spectra of various *** potential for carcinogenesis, teratogenesis, sterility and mutagenesis lumped together asgenetic toxicity appears to originate almost uniformly from the cross-linking between complementarybases, i.e. malignant cross-linking, which is in accordance with di-region theory. Other forms ofcross-linking between non-complementary bases, benign cross-linkings, show bi-functional alkylationanticancer activity but lack genetic toxicity. The predictable design and synthesis of a highselectivity anticancer agent with high efficacy and low genetic toxicity, a goal long pursued incancer chemotherapy, have been realized for the first time in this laboratory by inhibitingmalignant and heightening benign cross-linking using the principles of di-region theory. A series ofpatented new anticanc

关键词： mechanism of carcinogenesis, di-region theory, minoplatin, selectivity of anticancer agent, cross-linking between DNA bases, anticancer platinum complexes, predictive design of anticancer agent, second generation anticancer agent.

Structure-based drug design of a novel family of chalcones as ppArα agonists:virtual screening,synthesis,and biological activities in vitro

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Acta pharmacologica Sinica 2007年第12期28卷 2040-2052页

作者： Xiang-hua LI~(2,3),Han-jun ZOU~(2,3),An-hui WU~2,Yang-liang YE~2,Jian-hua SHEN~(2,4)~2 Drug Discovery and design center,State Key Laboratory of Drug research,Shanghai Institute of Materia Medica,Chinese Academy ofSciences,Shanghai 201203,china Drug Discovery and design center State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Chinese Academy of Sciences Shanghai China

Aim:To design and synthesize a novel class of peroxisome proliferator-activatedreceptors (ppAr)α agonists,which is obtained by the combination of the classi-cal fibrate"head group",a linker with appropriate length and a ***:Thirty seven compounds were designed and identified employing the virtualscreening *** compounds were then selected for synthesis and bioas-say according to the virtual screening results,structural similarity,and ***:Six new compounds (4b and 4d-h) were synthesized *** were found to be potent ppArα agonists,compound 4 h being themost prominent with a 50% effective concentration value of 0.06 μmol/***:This study provides a promising novel family of chalcones with a potentialhypolipidemic effect.

关键词： peroxisome proliferator-activated receptors drug design virtual screening

research ON STABILITY OF OpEN BOTTOM STOrAGE pLATFOrM

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Journal of Hydrodynamics 1999年第2期11卷 14-19页

作者： Qi Xin-yuan Jin Chen-yi Chen Wei-qi Chen Juan-fang(china Ship Scientific research center, Wuxi 214082, p. r. china) china Ship Scientific research Cent Wuxi China

In this paper, we present a new type of offshore structure, open bottomstorage platform, and its theoretical and experimental studies of its stability. In order tooptimize the design of column length and storage tank of the open bottom storage platform, we discuss the effect of air chamber length and storage on the stability of open bottom storage platform.

关键词： ocean engineering open bottom storage platform stability