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Ashkin-Teller Formalism for Elastic Response of DNA Molecule to External Force and Torque

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Communications in Theoretical Physics 2008年第2期49卷 525-528页

作者： CHANG Zhe~1 WANG Ping~(1,2) ZHENG Ying-Hong~(1,2) 1 Institute of High Energy Physics,the chinese academy of sciences,P.O.Box 918(4),Beijing 100049,china 2 graduate school,the chinese academy of sciences,Beijing 100049,china Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 918(4) Beijing 100049 China graduate school the Chinese Academy of Sciences Beijing 100049 China

We propose an Ashkin Teller-like model for elastic response of DNA molecule to external force and *** base-stacking interaction is described in a simple and uniform *** obtain the phase diagram of dsDNA,andin particular,the transition from B form to the S state induced by stretching and *** elastic response of thessDNA is presented also in a unified *** close relation of dsDNA molecule structure with elastic response isshown *** calculated folding angle of the dsDNA molecule is 59.2°.

关键词： dsDNA elastic property

Kinetics and reaction mechanism of phenol hydroxylation catalyzed by La-Cu_4FeAlCO_3

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Science china Chemistry 2005年第6期48卷 530-537页

作者： CHEN Chunxia1,2, XU Chenghua1, FENG Liangrong1, SUO Jishuan1 & QIU Fali1 1. Chengdu Institute of Organic Chemistry, chinese academy of sciences, Chengdu 610041, china 2. graduate school of the chinese academy of sciences, Beijing 100039, china 1. Chengdu Institute of Organic Chemistry Chinese Academy of Sciences 610041 Chengdu China 2. graduate school of the chinese academy of sciences 100039 Beijing China

The present work synthesizes La-Cu4FeAlCO3 catalyst under microwave irradiation and characterizes its structure using XRD and IR techniques. The results show that the obtained La-Cu4FeAlCO3 has a hydrotalcite structure. In the phenol hydroxylation with H2O2 catalyzed by La-Cu4FeAlCO3, the effects of reaction time and phenol/H2O2 molar ratio on the phenol hy-droxylation, and relationships between the initial hydroxylation rate with concentration of the catalyst, phenol, H2O2 and reaction temperature are also investigated in details. It is shown the phenol conversion can reach 50.09% (mol percent) in the phenol hydroxylation catalyzed by La-Cu4FeAlCO3, under the reaction conditions of the molar ratio of phenol/H2O2 1/2, the amount ratio of phenol/catalyst 20, reaction temperature 343 K, reaction time 120 min, 10 mL distilled water as solvent. Moreover, a kinetic equation of v = k[La ? Cu 4 FeAlCO 3 ][C 6 H 5 OH][H 2 O 2]. and the activation energy of Ea=58.37 kJ/mol are obtained according to the kinetic studies. Due to the fact that the HO-Cu+-OH species are detected in La-Cu4FeAlCO3/H2O2 system by XPS, the new mechanism about the generation of hydroxyl free radicals in the phenol hydroxylation is pro-posed, which is supposed that HO-Cu+-OH species are transition state in this reaction.

关键词： rare earth, hydrotalcite, microwave irradiation, phenol hydroxylation, kinetics, reaction mechanism.

Isospin and symmetry energy study in nuclear EOS

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Science china(Physics,Mechanics & Astronomy) 2011年第S1期54卷 141-148页

作者： TIAN WenDong1, MA YuGang1, CAI XiangZhou1, FANG DeQing1, WANG HongWei1 & WU HongLi1,2 1 shanghai Institute of Applied Physics, chinese academy of sciences, shanghai 201800, china 2 graduate school of University of Science and Technology of china, Hefei 230026, china 1. shanghai Institute of Applied Physics Chinese Academy of Sciences Shanghai 201800 China 2. graduate school of University of Science and Technology of china Hefei 230026 China

This paper summarizes the isoscaling and isospin related studies in asymmetry nuclear reactions by different dynamic and sta tistical models. Isospin dependent quantum molecular dynamics model (IQMD) and lattice gas model (LGM) are used to study the isoscaling properties and isoscaling parameters dependence on incident energies, impact parameters, temperature and other parameters. In the LGM model, the signal of phase transition has been found in free neutron (proton) chemical potential dif ference Δμn or Δμp as a function of temperature, or in free neutron and proton chemical potential difference Δμn-Δμp. Density dependence of symmetry energy coefficient Csym(ρ/ρ0) is also studied in the frame of LGM, with the potential parameters which can reproduce the nuclear ground state property, soft density dependence of symmetry energy is deduced from the sim ulation results. Giant dipole resonance (GDR) induced by isospin asymmetry in entrance channel is also studied via IQMD model, and the dynamic dipole resonance shows isospin sensitivity on the isospin asymmetry of entrance channel and sym metry energy of the nuclear equation of state (EOS). GDR can also be regarded as a possible isospin sensitive signature.

关键词： nuclear EOS isospin isoscaling density giant dipole resonance

Integrated precise orbit determination of Shenzhou IV unmanned spacecraft

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Science china(Technological sciences) 2004年第5期47卷 518-525页

作者： L Congmin1,2, GU Yidong3, LIN Baojun3 & GUO Jiong3 1. Center for Space Science and Applied Research, chinese academy of sciences, Beijing 100080, china 2. graduate school of the chinese academy of sciences, Beijing 100039, china 3. General Establishment of Space Science and Application, chinese academy of sciences, Beijing 100080, china Correspondence should be addressed to L Congmin 1. Center for Space Science and Applied Research Chinese Academy of Sciences 100080 Beijing China 2. graduate school of the chinese academy of sciences 100039 Beijing China 3. General Establishment of Space Science and Application Chinese Academy of Sciences 100080 Beijing China

Considering the characteristic orbit of Shenzhou IV spacecraft and the advantages and disadvantages of several types of domestic orbit measurements, a scheme of IPOD is determined, which uses GPS, SLR and USB observation data jointly plus precise ionosphere corrections to GPS observation data. IPOD system and mathematic models of OD are introduced. The results of different joint OD are analyzed using true observation data, and show that radial accuracy is better than 2 m.

关键词： Shenzhou IV unmanned spacecraft integrated precise orbit determination GPS SLR USB.

Theoretical critical value curve and driving force formation of ecological migration in the arid land

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chinese Science Bulletin 2006年第A01期51卷 196-203页

作者： ZHU Zi’an & ZHANG Xiaolei Xinjiang Institute of Ecology and Geography, chinese academy of sciences, Urumqi 830011, china The graduate school of the chinese academy of sciences, Beijing 100039, china Xinjiang Uygur Autonomous Region Development and Reform Commission, Urumqi 830002, china chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China chinese Acad Sci Grad Sch Beijing 100039 Peoples R China Xinjiang Uygur Autonomous Reg Dev & Reform Commis Urumqi 830002 Peoples R China

干旱陆地的易碎的 eco 环境的特征确定它骚乱抵抗的能力更低。在干旱陆地的自然荒芜的绿洲在在宽 Gobi 沙漠散布的马赛克补丁。人口分发是极大地依赖于水资源。人口与驱散的分发，简单生产和生活被描绘风格，和贫穷和遥远。生态的迁居... 详细信息

干旱陆地的易碎的 eco 环境的特征确定它骚乱抵抗的能力更低。在干旱陆地的自然荒芜的绿洲在在宽 Gobi 沙漠散布的马赛克补丁。人口分发是极大地依赖于水资源。人口与驱散的分发，简单生产和生活被描绘风格，和贫穷和遥远。生态的迁居被执行的原因躺在生态的问题。生态的降级是生态的迁居的主要驱动力。然后，驱动力的力量取决于生态的降级的度。因此，是否执行生态的移植取决于生态的降级的程度。理论上，为在干旱陆地的精明的生态的移植的批评的值曲线通过生态学的相对问题的全面研究被提出，经济等等，在干旱陆地与生态的移植经验结合了，并且基于干旱环境的特征。在这篇文章，与这条曲线，理论研究和生态的迁居的一些实践从不做作的行为和生态的移植的驱动力形成的政府行为的观点被做了。它分析活跃驱动力(因素) 和否定力量(因素) ，并且指出预定和在干旱陆地实现生态的迁居的步骤。理论曲线表达某些创见和适用性，它为为实现生态的迁居工程评估生态的降级和理论底的度提供一个量的方法。

关键词：生态迁移临界值驱动力贫瘠地

A tentative study for the prediction of the CME related geomagnetic storm intensity and its transit time

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Science china(Technological sciences) 2005年第6期48卷 648-668页

作者： ZHAO Xinhua1,2 & FENG Xueshang1,3 1. SIGMA Weather Group, Key Laboratory of Space Weather, Center for Space Science and Applied Re-search, chinese academy of sciences, Beijing 100080, china 2. graduate school of the chinese academy of sciences, Beijing 100039, china 3. school of Geophysics and Geoinformation Systems, china University of Geosciences, Beijing 100083, china 1. SIGMA Weather Group Key Laboratory of Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences 100080 Beijing China 2. graduate school of the chinese academy of sciences 100039 Beijing China 3. school of Geophysics and Geoinformation Systems China University of Geosciences 100083 Beijing China

Using 80 CME-ICME events during 1997.1―2002.9, based on the eruptive source locations of CMEs and solar magnetic field observation at the photosphere, a current sheet magnetic coordinate (CMC) system is established in order to study the propagation of CME and its geoeffectiveness. In context of this coordinate system, the effect of the eruptive source location and the form of heliospheric current sheet (HCS) at the eruptive time of CME on the geomagnetic storm intensity caused by CME and the CME’s transit time at the Earth is investigated in detail. Our preliminary conclusions are: 1) The geomagnetic disturbances caused by CMEs tend to have the so-called “same side-opposite side effect”, i.e. CMEs erupt from the same side of the HCS as the earth would be more likely to arrive at the earth and the geomagnetic disturbances associated with them tend to be of larger magnitude, while CMEs erupting from the opposite side would arrive at the earth with less probability and the corresponding geomagnetic disturbance magnitudes would be relatively weaker. 2) The angular separation between the earth and the HCS affect the corresponding disturbance intensity. That is, when our earth is located near the HCS, adverse space weather events occur most probably. 3) The erupting location of the CME and its nearby form of HCS will also affect its arrival time at the earth. According to these conclusions, in this context of CMC coordinate we arrive at new prediction method for estimating the geomagnetic storm intensity (Dstmin) caused by CMEs and their transit times. The application of the empirical model for 80 CME-ICME events shows that the relative error of Dst is within 30% for 59% events with Dstmin≤?50 nT, while the averaged absolute error of transit time is lower than 10 h for all events.

关键词： coronal mass ejections, current sheet magnetic coordinate system, geomagnetic storm intensity, transit time, prediction method.

Geographical Agglomeration of chinese Manufacturing Industries

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中国人口·资源与环境：英文版 2007年第2期5卷 3-11页

作者： Zhang Hua 1, 2, Zheng Wei3 1. Institute of Geographical sciences and Natural Resources Research, chinese academy of sciences, Beijing 100101, china 2. graduate school of the chinese academy of sciences, Beijing 100039, china 3. school of Geography, Beijing Normal University, Beijing 100875, china Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China graduate school of the chinese academy of sciences Beijing 100039 China school of Geography Beijing Normal University Beijing 100875 China

Based on the plant level data from the First National Census of Basic Units, the Second National Census of Basic Units, and the First National Economic Census of china, this paper ex- amines the geographical agglomeration of chinese manufacturing industries at a more disaggregated level both by industrial classi-fication and spatial unit analysis. Applying the agglomeration index proposed by Maurel and Sedillot, studies show that the most agglomerated industries are resource-intensive, and capital and technology intensive while industries demanding localized inputs or serving localized markets or favored by local governments are fairly dispersed. The more disaggregated industries are more spa- tially agglomerated. At the finer spatial scale, industries are more dispersed. Results indicate that within-county spillovers are stronger than nearby-county spillovers, and within-prefecture spillovers are stronger than nearby prefecture spillovers. Local- ized spillovers are still quite substantial at a range beyond that of counties. Comparing the agglomeration index of chinese manu- facturing industries in 1996, 2001 and 2004, agglomeration seems to be a general tendency. Results also indicate that some industries have experienced remarkable changes in their levels of agglom- eration in the period 1996–2004.

关键词： industrial agglomeration manufacturing industries the MS index

Prediction of Debris-flow Danger Area by Combining Hydrological and Inundation Simulation Methods

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Journal of Mountain Science 2011年第1期8卷 1-9页

作者： CUI Peng Key Laboratory of Mountain Hazards and Earth Surface Process Chinese Academy of Sciences Chengdu 610041 China Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China graduate school of chinese academy of sciences Beijing 100049 China

Debris flows have caused serious human casualties and economic losses in the regions strongly affected by the Ms8.0 Wenchuan earthquake of 2oo8. Debris flow mitigation and risk assessment is a key issue for reconstruction. The existing methods of inundation simulation are based on historical disasters and have no power of prediction. The rain- flood method can not yield detailed flow hydrograph and does not meet the need of inundation simulation. In this paper, the process of water flow was studied by using the Arc-SCS model combined with hydraulic method, and then the debris flow runoff process was calculated using the empirical formula combining the result from Arc-SCS. The peak discharge and runoff duration served as input of inundation simulation. Then, the dangerous area is predicted using kinematic wave method and Manning equation. Taking the debris flow in Huashiban gully in Beichuan County, Sichuan Province, china on 24 Sep. 2oo8 as example, the peak discharge of water flow and debris flow were calculated as 35.52 m3·s-1 and 215.66 m3·s-, with error of 4.15% compared to the measured values. The simulated area of debris-flow deposition was 161,500 m2, vs. the measured area of 144,097 m2, in error of 81.75%. The simulated maximum depth was 12.3 m, consistent with the real maximum depth between lO and 15 m according to the field survey. The minor error is mainly due to the flow impact on buildings and variations in cross-section configuration. The present methodology can be applied to predict debrisflow magnitude and evaluate its risk in other watersheds inthe earthquake area.

关键词： Debris flow Arc-SCS model Inundation simulation Risk analysis Wenchuan earthquake

Temporal-spatial variations of euphotic depth of typical lake regions in Lake Taihu and its ecological environmental significance

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Science china Earth sciences 2006年第4期49卷 431-442页

作者： ZHANG Yunlin1, 2, QIN Boqiang1, HU Weiping1, WANG Sumin1, CHEN Yuwei1 & CHEN Weimin1 1. Nanjing Institute of Geography & Limnology, chinese academy of sciences, Nanjing 210008, china 2. graduate school of the chinese academy of sciences, Beijing 100039, china 1. Nanjing Institute of Geography & Limnology Chinese Academy of Sciences Nanjing 210008 China 2. graduate school of the chinese academy of sciences Beijing 100039 China

By using the data of underwater irradiance measured in the different lakeregions of Lake Taihu during 1998—2004 and total suspended solids (TSS), wind speeds of the total13 stations in typical lake regions during 1993—2003, this paper analyzes the factors ofinfluencing on PAR (pho-tosynthetically available radiation) attenuation, euphotic depth, andpresents the temporal and spatial variations of euphotic depth of typical lake regions in LakeTaihu, and the spectral distributions of euphotic depth at station 2. The results show that theconcentration of TSS is the most important factor impacting PAR attenuation, followed by chlorophylla; chromophoric dissolved organic matter (CDOM) has little impact on the PAR euphotic depth. During1993—2003, the mean yearly PAR euphotic depths of the typical lake regions ranged from 1.04 to1.95 m with a mean value of 1.35±0.23 m. The PAR euphotic depth fell into 3 spatial zone types:Type Ⅰ, the lowest, including the lake center and the inflows of rivers; Type Ⅱ, intermediate,including Meiliang Bay, Wulihu Lake and Gonghu Bay; Type Ⅲ, the greatest, including the East LakeTaihu; corresponding mean depths were approximately 1.1, 1.4, 2.0 m, respectively. The seasonalvariations of euphotic depths were not quite the same in different lake regions. In the lake center,the mean values of PAR euphotic depth in summer and autumn were significantly greater than those inwinter and spring; in the Meiliang Bay, winter means were significantly greater than in the otherthree seasons; in the East Lake Taihu, winter means were significantly less than in the other threeseasons. However, no distinct seasonal change was recorded in the Wulihu Lake, Gonghu Bay and theinflows of rivers. The spectral distributions of euphotic depth present a minimal value at the bluelight wave band of 400 nm, and a peak at the green light wave band of around 580 nm. In 1998 and1999, based on the seasonal many-day continuous measurements, the PAR euphotic depths at station 2w

关键词： lake taihu euphotic depth diffuse attenuation coefficient total suspendedsolid ecological