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DNA computing model based on lab-on-a-chip and its application on solving the timetabling problem

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Progress in Natural science:Materials International 2008年第5期18卷 633-637页

作者： Fengyue Zhang a,1, Bo Liu b,1, Wenbin Liu c, Qiang Zhang d a Department of Biomedical Engineering, School of Life science and technology, Beijing institute of technology, Beijing 100081, China b Chinese Academy of Inspection and Quarantine, Beijing 100029, China c College of Computer science and Engineering, Wenzhou University, Wenzhou, Zhejiang 325027, China d Liaoning Key Laboratory of Intelligent Information Processing, Dalian University, Dalian, Liangning 116622, China Department of Biomedical Engineering School of Life Science and Technology Beijing Institute of Technology Beijing 100081 China Chinese Academy of Inspection and Quarantine Beijing 100029 China College of Computer science and Engineering Wenzhou University Wenzhou Zhejiang 325027 China Liaoning Key Laboratory of Intelligent Information Processing Dalian University Dalian Liangning 116622 China

The essential characteristic of DNA computation is its massive parallelism in obtaining and managing information. With the develop- ment of molecular biology technique, the eld of DNA computation has made a great progress. By using an advanced biochip technique, laboratory-on-a-chip, a new DNA computing model is presented in the paper to solve a simple timetabling problem, which is a special ver- sion of the optimization problems. It also plays an important role in education and other industries. With a simulated biological experiment, the result suggested that DNA computation with lab-on-a-chip has the potential to solve a real complex timetabling problem.

关键词： DNA computing Timetabling problem Lab-on-a-chip

molecular dynamics simulations of thermal effects in nanometric cutting process

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science China(Technological sciences) 2010年第3期53卷 870-874页

作者： GUO YongBo,LIANG YingChun,CHEN MingJun,BAI QingShun&LU LiHua Precision Research Engineering institute,Harbin institute of technology,Harbin 150001,China Precision Research Engineering institute Harbin Institute of Technology Harbin China

Understanding the basic action of how material removing in nanoscale is a critical issue of producing well-formed *** order to clarify thermal effects on material removal at atomic level,molecular dynamics(MD)simulations of nanometric cutting of mono-crystalline copper are performed with Morse,EAM and Tersoff *** effects of cutting speed on temperature distribution are *** simulation results demonstrate that the temperature distribution shows a roughly concentric shape around shear zone and a steep temperature gradient lies in diamond tool,a relative high temperature is located in shear zone and machined surface,but the highest temperature is found in *** a high cutting speed mode,the atoms in shear zone with high temperature implies a large stress is built up in a local region.

关键词： molecular dynamics nanometric cutting temperature distribution

Oxygen pressure dependent electro-resistance in La_(0.9)Sr_(0.1)MnO_3 thin films grown by laser molecular beam epitaxy

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science China(Physics,Mechanics & Astronomy) 2008年第3期51卷 232-236页

作者： OUYANG SiHua1,2,WANG ChunChang2,LIU GuoZhen2,HE Meng2, JIN KuiJuan2,DANG ZhiMin1 & L HuiBin21 College of Materials science and Engineering,Beijing University of Chemical technology,Beijing 100029,China 2 Beijing national Laboratory for Condensed Matter Physics,institute of Physics,Chinese Academy of sciences,Beijing 100080,China College of Materials science and Engineering Beijing University of Chemical Technology Beijing China Beijing national Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing China

We report here studies on the influence of oxygen pressure on the electroresis-tance behavior of La0.9Sr0.1MnO3 thin films fabricated by laser molecular beam epi-taxy. It was found that the film deposited at lower oxygen pressure shows larger c-axis parameter,higher resistance,and more distinct electroresistance. These results reveal that the electroresistance of manganite thin films can be tuned by the conditions of film fabrication.

关键词： La0.9Sr0.1MnO3 thin film electroresistance effect laser molecular beam epitaxy

A Research on Investment Casting technology of Ti Alloys

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Journal of Materials science & technology 2000年第1期16卷 76-78页

作者： Huiguan WAN, Xiumei QI, Jing TIAN, Yuyong CHEN, Weiqiang ZHA and Jun JIA (national Key Laboratory of Precision Hot Processing of Metals, Harbin institute of technology, Harbin 150001, China) national Key Laboratory of Precision Hot Processing of Metals Harbin Institute of Technology Harbin 150001 China

In this research, the materials and the compositions of the surface slurries were chosen by considering the characteristics of Ti investment casting. The effects of solid-liquid ratios on the properties of the slurry and the effects of baking temperatures on the flexural strength have also been investigated. Flawless shells having smooth inner surface were manufactured with proper technology. Ti and its alloys were melted and poured by water-cooled Cu crucible vacuum induction furnace. The qualities of the investment castings made accordingly were studied and analyzed.

关键词： In Ti A Research on Investment Casting technology of Ti Alloys

Tyrosine Hydroxylase as a Target for Deltamethrin in the Nigrostriatal Dopaminergic Pathway

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Biomedical and Environmental sciences 2006年第1期19卷 27-34页

作者： GONG-PING LIU QIANG MA NIAN SHI Department of Toxicology MOE key Laboratory of Environmental and Health Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei China Receptor Biology Laboratory Toxicology and Molecular Biology Branch Health Effects Laboratory Division National Institute for Occupational Safety and Health Centers for Disease Control and Prevention Morgantown WV 26505 USA

Objective To study the effects of deltamethrin on tyrosine hydroxylase in nigrostriatum of male rats. Methods Sprague-Dawley rats were daily treated with deltamethrin at 6.25 or 12.5 mg/kg body weight by gavage for 10 days. Then HPLC-fluorescence detection was used to analyze the contents of dopamine （DA）, 3,4-dihydmxyphenylacetic acid （DOPAC） and homoranillic acid （HVA） in substantial nigra and striatum. The activities of tyrosine hydroxylase （TH） were also detected by HPLC-fluorescence detection. TH mRNA or TH protein levels were measured by RT-PCR and immunohistochemistry method. Results The content of DA in stfiatum was significantly decreased by the treatments, suggesting an inhibition of DA synthesis by deltamethrin. The contents of DA metabolites DOPAC and HVA increased, indicating increased dopamine turnover. Furthermore, deltamethrin significantly decreased the activity, as well as the mRNA and protein levels of TH. Conclusions These findings reveal a novel aspect of deltamethfin neurotoxicity and suggest tyrosine hydroxylase as a molecular target of deltamethin on dopamine metabolism in the nigrostriatal pathway.

关键词： Deltamethrin Nigrostriatum Dopamine Tyrosine hydroxylase Parkinson's disease

Research on the influence of machining introduced sub-surface defects and residue stress upon the mechanical properties of single crystal copper

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science China(Technological sciences) 2010年第12期53卷 3161-3167页

作者： CHEN MingJun, XIAO GaoBo, CHEN JiaXuan & WU ChunYa Harbin institute of technology, Harbin 150001, China Harbin institute of technology Harbin China

Large scale molecular dynamics simulations of nanomachining and stretching of single crystal copper are performed to analyze the machining process’ influence on the material’s mechanical properties. The simulation results show that the machining process will introduce interfacial defects inside the specimen and enhance the compressive stress beneath the surface. Gener- ally speaking, interfacial defects lead to the decrease of the strength limit, while residue compressive stress can enhance the elastic limit and even the strength limit. Various machining parameters are adopted to investigate their influence on the me- chanical behavior of machined specimen. Lower cutting speed and smaller cutting depth lead to less defects and greater residue compressive stress, which brings about better mechanical properties. The elastic limit increases by 36.8% under the cutting depth of 0.73 nm and decreases by 21.1% under the cutting depth of 1.46 nm. The strength limit increases by 7.7% under the cutting speed of 100 m/s and decreases by 28.2% under the cutting speed of 300 m/s.

关键词： nanomachining deformation residue stress molecular dynamics dislocations

CHEMICAL STRUCTURE DEPENDENCE OF THE INTERNAL ENERGY CONTRIBUTION IN RUBBER ELASTICITY

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Chinese Journal of Polymer science 2001年第5期19卷 447-449页

作者： Juan Sun Xiao-zhen Yang Polymer Physics Laboratory Center for molecular sciences, institute of Chemistry Chinese Academy of sciences Beijing 100080 China 中科院化学所高分子物理及化学国家重点实验室北京

Conformational elasticity theory recently developed has been used to explore the internal energy contribution to the elastic force f(e)/f as a function of strain for poly(cis-1,4-isoprene) and poly(trans-1,4-isoprene). Calculated f(e)/f values are in good agreement with those obtained experimentally. Results show that behavior of f(e)/f is mainly contributed by chemical structure, or intramolecular interaction, supporting the experimental observations, and that the internal energy contribution is strain dependent.

关键词： conformational elasticity theory internal energy contribution poly(cis-1,4-isoprene) poly(trans-1,4-isoprene)

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活性碳纳米管的制备及其结构的研究(英文)

新型炭材料 2004年第3期19卷 197-203页

作者：刘云芳沈曾民横川清志马宝海于建民北京化工大学炭纤维及复合材料研究所北京100029 国家先进工业科学与技术研究所结构与工程材料研究室

　采用KOH对催化裂解法制备的碳纳米管进行活化处理,以提高碳纳米管的比表面积,并调整孔结构。研究了活化温度和碱用量对活化碳纳米管的收率、比表面积、晶体结构、微观形貌和孔结构的影响。实验结果表明,通过KOH活化能有效地提高碳纳... 详细信息

　采用KOH对催化裂解法制备的碳纳米管进行活化处理,以提高碳纳米管的比表面积,并调整孔结构。研究了活化温度和碱用量对活化碳纳米管的收率、比表面积、晶体结构、微观形貌和孔结构的影响。实验结果表明,通过KOH活化能有效地提高碳纳米管的比表面积,调整孔隙结构。随活化温度升高,活化碳纳米管的收率逐渐降低,比表面积和孔容则逐渐提高。通过活化,碳纳米管的内孔得到释放,有大量的微孔、中孔结构形成。增大碱用量时,收率降低,而比表面积和微孔孔容增加,在比值为7∶1时比表面积达到最大值。通过研究发现,制备高比表面积碳纳米管的优化工艺条件为:KOH CNTs的质量比为7∶1,活化温度为900℃。此条件下所得碳纳米管的比表面积为360.1m2 g,比未活化碳纳米管的比表面积(24.5m2 g)提高了14倍。

关键词：比表面积活化温度收率制备孔容碳纳米管孔结构碱用量最大值微孔

Local Structure of Ge/Si(100) Self-Assembled Quantum Dots

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中国科学技术大学学报 2001年第3期31卷 282-288页

作者： Alexander V. Kolobov a) onleavefromA .F .IoffePhysico Technicalinstitute,StPetersburg,Russia (Joint Research Center for Atom technology national institute of advanced industrial science and technology, Tsukuba Central 4, 1 1 1 Higashi, Tsukuba 30 Joint Research Center for Atom technology national institute of advanced industrial science and technology 日本 30 5 8562

Local structure of uncapped and Si capped Ge quantum dots grown on Si(100) has been probed by X ray absorption fine structure spectroscopy. It is found that the uncapped Ge dots are partially oxidized and partially alloyed with Si. The amount of Ge present in the Ge phase is found to be about 20 30%. In the Si capped sample, Ge is found to be dissolved in silicon, the fraction of Ge atoms existing as pure Ge phase being not more than 10%.

关键词：自相似锗量子点局域结构 EXAFS XANES