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Theoretical study on S_1(~1B_(3u)) state electronic structure and absorption spectrum of pyrazine

science china chemistry 2008年第12期51卷 1166-1173页

作者： HE RongXing1, ZHU ChaoYuan 2, CHIN Chih-Hao3 & LIN Sheng-Hsien2,3 1 College of chemistry and Chemical Engineering, Southwest university, Chongqing 400715, china 2 department of applied chemistry, institute of molecular science and center for interdisciplinary molecular science, national chiao-tung university, hsinchu 300, china 3 institute of Atomic and molecular sciences, Academia Sinica, Taipei 106, china College of chemistry and Chemical Engineering Southwest University Chongqing China department of applied chemistry Institute of Molecular Science and Center for Interdisciplinary Molecular Science National Chiao-Tung University Hsinchu China institute of Atomic and molecular sciences Academia Sinica Taipei China

Making use of a set of quantum chemistry methods, the harmonic potential surfaces of the ground state (S0(1Ag)) and the first (S1(1B3u)) excited state of pyrazine are investigated, and the electronic structures of the two states are characterized. In the present study, the conventional quantum mechanical method, taking account of the Born-Oppenheimer adiabatic approximation, is adopted to simulate the absorp-tion spectrum of S1(1B3u) state of pyrazine. The assignment of main vibronic transitions is made for S1(1B3u) state. It is found that the spectral profile is mainly described by the Franck-Condon progression of totally symmetric mode ν6a. For the five totally symmetric modes, the present calculations show that the frequency differences between the ground and the S1(1B3u) state are small. Therefore the displaced harmonic oscillator approximation along with Franck-Condon transition is used to simulate S1(1B3u) absorption spectra. The distortion effect due to the so-called quadratic coupling is demonstrated to be unimportant for the absorption spectrum, except the coupling mode ν10a. The calculated S1(1B3u) ab-sorption spectrum is in reasonable agreement with the experimental spectra.

关键词： pyrazine absorption spectrum quantum mechanical method electronic structure

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Subchronic toxicological effects of aquatic nitrobenzene on Medaka and Chinese rare minnow

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science china chemistry 2007年第5期50卷 707-717页

作者： ZHOU QunFang1, FU JianJie1,2, MENG HaiZhen1,2, ZHU XueYan1,2, JIANG GuiBin1, ZHANG JianBin1, LIU JieMin2 & SHI GuoQing2 1 State Key Laboratory of Environmental chemistry and Ecotoxicology, Research center for Eco-environmental sciences, Chinese Academy of sciences, Beijing 100085, china 2 department of chemistry, School of applied science, university of science and Technology Beijing, Beijing 100083, china State Key Laboratory of Environmental chemistry and Ecotoxicology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing China department of chemistry School of Applied Science University of Science and Technology Beijing Beijing China

Based on the simulative exposure experiments of nitrobenzene to two small experimental fishes, Medaka (Oryzias latipes) and Chinese Rare Minnow (Gobiocypris rarus), it was found that nitrobenzene could decrease in a linear way in the static aquatic system. Both fishes could accumulate dose-related levels of nitrobenzene quickly and eliminate the compound rapidly when they were transferred to clean water. The Chinese rare minnow showed more sensitivity to the acute toxicity exposure of nitrobenzene than Medaka. Typical molecular biomarkers in oxidative defense system including superoxide dismu- tase (SOD), catalase (CAT) showed the chemical induced alterations. The changes of acetylcholi- nesterase (AChE) activities indicated that nitrobenzene might affect the normal neural function. Nitro- benzene exposure could also lead to obvious damaging effects on the target organs, such as gill and liver by hitopathological studies.

关键词： nitrobenzene, Medaka, Chinese rare minnow, bioaccumulation, elimination, molecular biomarkers, histopathological effects

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Formation and evolution mechanisms of large-clusters during rapid solidification process of liquid metal Al

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science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 101-112页

作者： LIU Rangsu, DONG Kejun, LIU Fengxiang, ZHENG Caixing, LIU Hairong & LI Jiyong department of applied Physics, Hunan university, Changsha 410082, china College of Materials science and Engineering, Hunan university, Changsha 410082, china College of chemistry and Chemical Engineering, Hunan university, Changsha 410082, china department of applied Physics Hunan University Changsha 410082 China College of Materials science and Engineering Hunan University Changsha 410082 China College of chemistry and Chemical Engineering Hunan University Changsha 410082 China

A molecular dynamics simulation study has been performed for the formation and evolution characteristics of nano-clusters in a large-scale system consisting of 400000 atoms of liquid metal Al. The center-atom method combined with pair-bond analysis technique and cluster-type index method (CTIM) has been applied here to describe the structural configurations of various basic clusters. It is demonstrated that both the 1551 bond-type and the icosahedral cluster (12 0 12 0) constructed by 1551 bond-types are dominant among all the bond-types and cluster-types, respectively, in the system and play a critical role in the microstructure transitions of liquid metal Al. The nano-clusters (containing up to 150 atoms) are formed by the combination of some middle and small clusters with distinctly different sizes, through mutual competition by unceasing annex and evolution in a seesaw manner (in turn of obtaining and losing),which do not occur as the multi-shell structures accumulated with an atom as the center and the surrounding atoms are arranged according to a certain rule. This is the essential distinction of nano-cluster in liquid metal from those obtained by gaseous deposition, ionic spray methods, and so on. Though the nano-clusters differ from each other in shape and size, all of them possess protruding corners that could become the starting points of various dendrite structures in the solidification processes of liquid metals.

关键词： liquid metal, solidification process, large-cluster configuration, evolution mechanism, computer simulation.

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Comparisons of Graph-structure Clustering Methods for Gene Expression Data

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Acta Biochimica et Biophysica Sinica 2006年第6期38卷 379-384页

作者： Zhuo FANG~1,Lei LIU~(2,4),Jiong YANG~3,Qing-Ming LUO~(1*),and Yi-Xue LI~(2*) ~1 Hubei Bioinformatics and molecular Imaging Key Laboratory,College of Life science and Technology, Huazhong university of science and Technology,Wuhan 430074,china ~2 Shanghai center for Bioinformatics Technology,Shanghai 200235,china ~3 department of EECS,Case Western Reserve university,Cleveland 44106,USA ~4 W.M.Keck center for Comparative and Functional Genomics,university of Illinois at Urbana-Champaign,Urbana 61801,USA Hubei Bioinformatics and molecular Imaging Key Laboratory College of Life Science and Technology Huazhong University of Science and TechnologyWuhan 430074 China Shanghai center for Bioinformatics TechnologyShanghai 200235 China W.M. Keck center for Comparative and Functional Genomics University of Illinois at Urbana-ChampaignUrbana 61801 USA department of EECS Case Western Reserve UniversityCleveland 44106 USA

Although many numerical clustering algorithms have been applied to gene expression dataanalysis,the essential step is still biological interpretation by manual *** correlation betweengenetic co-regulation and affiliation to a common biological process is what biologists ***,weintroduce some clustering algorithms that are based on graph structure constituted by biological *** applying a widely used dataset,we compared the result clusters of two of these algorithms in terms ofthe homogeneity of clusters and coherence of annotation and matching *** results show that theclusters of knowledge-guided analysis are the kernel parts of the clusters of Gene Ontology (GO)-Clustersoftware,which contains the genes that are most expression correlative and most consistent with ***,knowledge-guided analysis seems much more applicable than GO-Cluster in a largerdataset.

关键词： clustering expression pattern biological function

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Accurate prediction of interference minima in linear molecular harmonic spectra by a modified two-center model

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Chinese Physics B 2016年第3期25卷 163-168页

作者：崔鑫张頔玉陈高陈基根曾思良郭福明杨玉军 institute of Atomic and molecular Physics Jilin UniversityChangchun 130012China Jilin Provincial Key Laboratory of applied Atomic and molecular Spectroscopy Jilin UniversityChangchun 130012China School of science Changchun University of Science and TechnologyChangchun 130022China department of Physics and Materials Engineering Taizhou UniversityTaizhou 318000China institute of applied Physics and Computational Mathematics Beijing 100088China

We demonstrate that the interference minima in the linear molecular harmonic spectra can be accurately predicted by a modified two-center model. Based on systematically investigating the interference minima in the linear molecular harmonic spectra by the strong-field approximation （SFA）, it is found that the locations of the harmonic minima are related not only to the nuclear distance between the two main atoms contributing to the harmonic generation, but also to the symmetry of the molecular orbital. Therefore, we modify the initial phase difference between the double wave sources in the two-center model, and predict the harmonic minimum positions consistent with those simulated by SFA.

关键词： high-order harmonic generation molecular harmonics

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Comparison of dark energy models:A perspective from the latest observational data

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中国科学：物理学、力学、天文学英文版 2010年第9期53卷 1631-1645页

作者： LI Miao1,2,LI XiaoDong2,3 & ZHANG Xin1,4 1Kavli institute for Theoretical Physics china,Chinese Academy of sciences,Beijing 100190,china 2Key Laboratory of Frontiers in Theoretical Physics,institute of Theoretical Physics,Chinese Academy of sciences,Beijing 100190,china 3interdisciplinary center for Theoretical Study,university of science and Technology of china,Hefei 230026,china 4department of Physics,College of sciences,Northeastern university,Shenyang 110004,china Kavli institute for Theoretical Physics china Chinese Academy of Sciences Beijing China Key Laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences Beijing China interdisciplinary center for Theoretical Study University of Science and Technology of China Hefei China department of Physics College of Sciences Northeastern University Shenyang China

We compare some popular dark energy models under the assumption of a flat universe by using the latest observational data including the type Ia supernovae Constitution compilation,the baryon acoustic oscillation measurement from the Sloan Digital Sky Survey,the cosmic microwave background measurement given by the seven-year Wilkinson Microwave Anisotropy Probe observations and the determination of H0 from the Hubble Space *** comparison statistics such as the Bayesian and Akaike information criteria are applied to assess the worth of the *** statistics favor models that give a good fit with fewer *** on this analysis,we find that the simplest cosmological constant model that has only one free parameter is still preferred by the current *** other dynamical dark energy models,we find that some of them,such as the αdark energy,constant w,generalized Chaplygin gas,Chevalliear-Polarski-Linder parametrization,and holographic dark energy models,can provide good fits to the current data,and three of them,namely,the Ricci dark energy,agegraphic dark energy,and Dvali-Gabadadze-Porrati models,are clearly disfavored by the data.

关键词： dark energy models observational constraints model comparison information criteria

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Investigation on the influence of atomic potentials on the above threshold ionization

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Chinese Physics B 2014年第5期23卷 238-243页

作者：田原野李苏宇魏珊珊郭福明曾思良陈基根杨玉军 institute of Atomic and molecular Physics Jilin University Data center for High Energy Density Physics Institute of Applied Physics and Computational Mathematics science and Technology Computation Physics Laboratory Institute of Applied Physics and Computational Mathematics department of Physics and Materials Engineering Taizhou University

We systematically investigate the influence of atomic potentials on the above-threshold ionization （ATI） spectra in one-dimensional （1D） cases and compare them with the three-dimensional （3D） case by numerically solving the time-dependent Schrrdinger equation. It is found that the direct ionization plateau and the rescattering plateau of the ATI spectrum in the 3D case can be well reproduced by the 1D ATI spectra calculated from the supersolid-core potential and the soft-core potential, respectively. By analyzing the factors that affect the yield of the ATI spectrum, we propose a modified-potential with which we can reproduce the overall 3D ATI spectrum. In addition, the influence of the incident laser intensities and frequencies on the ATI spectra calculated from the proposed modified potential is studied.

关键词： above threshold ionization model potential angular distribution of photoelectron

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Nanotechnology for bioseparations

Nanotechnology for bioseparations

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30th International Symposium on Capillary Chromatography、4th GC×GC Symposium、16th national Symposium and Exhibition on Chromatography,i.e. 1st Dalian International Symposium and Exhibition on Chromatography

作者： Baba Y.~(1-5 *) 1.department of applied chemistry Graduate School of Engineering Nagoya university 2.MEXT Innovative Research center for Preventive Medical Engineering Nagoya university 3.Plasma Nanotechnology Research center Nagoya university 4.Health Technology Research center national institute of Advanced Industrial science and Technology (AlST) 5.institute for molecular science national institute for Natural sciences

＜正＞This lecture will describe the recent development of nanobiotechnologies based on the nanofabrication, molecular nanotechnoiogy,and nanomaterials for bioanalysis and biomedical *** technologies allow us to develop novel methods to analyze several biomolecules,including DNA,RNA,protein,peptide, polysaccharide,and *** of nano-pillar,which is 200 nm wide and 4000 nm tall,is successfully applicable to fast separation of DNA within 10-25 ***-ball,fabricated by molecular nanotechnology,of which diameter is 50 nm,is developed and successfully applied for fast separation of DNA fragments from 100 bp to 15 *** cellulose,which is 50 nm diameter biofiber,is found to be useful high sensitive detection of biomolecule based on the optical confined effect as well as fast analysis of *** nano-biodevice is extremely useful for fast separation of protein samples from several kDa to 200 kDa within 15 seconds. Utilizing this technique,complex protein mixture extracted from human T cell line,lymphoblastic Jurkat cells, were separated within 15s with high *** methods we have taken appear suitable for biomedical and clinical applications,including SNPs analysis,mutation analysis,haplotyping,DNA diagnosis,protein expression analysis,immunoassay,protein disease marker detection,point-of-care *** methods are also applicable to molecular imaging of cancer cell and possible photodynamic therapy of cancer.

关键词： Nanotechnoiogy Biodevice Protein DNA Cell

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酵母内含子在基因序列中的分布对基因转录效率的影响

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生物化学与生物物理进展 2003年第6期30卷 945-949页

作者：张静石秀凡杨恒芬云南大学应用统计中心中国科学院昆明动物研究所

对酵母中高效转录和低效转录基因内含子序列寡核苷酸使用情况的对照分析 ,显示两类内含子的序列结构有差异 ,并且高效转录基因内含子序列含有较多潜在的转录因子结合位点 ,由此推测内含子可能参与基因转录的调控 .这个结论有待更多的数... 详细信息

对酵母中高效转录和低效转录基因内含子序列寡核苷酸使用情况的对照分析 ,显示两类内含子的序列结构有差异 ,并且高效转录基因内含子序列含有较多潜在的转录因子结合位点 ,由此推测内含子可能参与基因转录的调控 .这个结论有待更多的数据证实 .对内含子和外显子在两组基因序列中的分布 (长度、位置等 )进行详细比较分析后显示 ,高效转录基因内含子和低效转录基因内含子的长度有比较明显的界限 .两组基因中外显子长度的均值虽然有些差异 ,却没有明显的界限 .基因序列长度与外显子长度的情况相似 .虽然内含子的相对位置在两类基因中都很靠近 5′端 ,但是从实际位置看 ,高效转录基因中比较多的内含子很靠近基因的 5′端 ,有些则位于 5′ UTR区域 .这些结果提示 ,基因的转录效率与内含子的长度有关 ,与外显子及基因序列的长度无关 ,内含子的位置也可能影响转录效率 ,内含子对基因转录的调控可能与基因上游的转录调控有关联。

关键词：酵母基因转录频率内含子长度内含子位置基因序列基因转录

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反射式扫描近场光学显微镜及其成像

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中国激光 1998年第9期25卷 852-858页

作者：王刚赵钧刘静勇张培林清华大学现代应用物理系和单原子分子测控中心

介绍了一种光纤探针同时作为光源和探测器的反射式扫描近场光学显微镜，该装置通过采用相干探测、偏振分光等技术克服了该类显微镜所普遍面临的噪声背景干扰问题，具有较高的光学信噪比，并通过样品纵向振动调制锁相实现了对样品表面光... 详细信息

介绍了一种光纤探针同时作为光源和探测器的反射式扫描近场光学显微镜，该装置通过采用相干探测、偏振分光等技术克服了该类显微镜所普遍面临的噪声背景干扰问题，具有较高的光学信噪比，并通过样品纵向振动调制锁相实现了对样品表面光强梯度信号的探测成像，进一步改善了成像质量。成像研究表明该装置可对近场衰逝分量进行有效探测并实现了超衍射极限成像。

关键词： SNOM 反射模式衰逝波相干探测光学显微镜

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