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A modified multi-reference second order perturbation theory

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中国科学：化学英文版 2010年第4期53卷 933-939页

作者： LI AnYang1, HAN HuiXian2, SUO BingBing3. WANG YuBin3.& WEN ZhenYi3.1institute of Computational Chemistry, Chongqing University of Post and Telecommunications, Chongqing 400065, china 2Department of Physics, Northwest University, Xi’ an 710069, china 3.0} of Modern Physics, Northwest University, Xi’ an 710069, china 1. institute of Computational Chemistry Chongqing University of Post and Telecommunications Chongqing 400065 China2. Department of Physics Northwest University Xi’ an 710069 China3. Institute of Modern Physics Northwest University Xi’ an 710069 China

A new scheme with extended model space is proposed to improve the calculation of multi-reference second order perturbation theory (MRPT2). The new scheme preserves the concise code structure of the original program, and avoids intruder states in constructions of the potential energy surface, which is confirmed by a series of comparable calculations. The new MRPT2 program is an available tool for the research of molecular excited states and electronic spectrum.

关键词： perturbation theory multi-reference intruder state

SYNTHESIS　OF　BENZO－15－CROWN－5　PHENOL－FORMALDEHYDE　RESIN　FOR　LITHIUM　ISOTOPE　SEPARATION

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Chinese Chemical Letters 1996年第3期7卷 289-292页

作者： YOU Heng SHI Qun YAN Duo Yuan WANG Xiao Zhi ZHANG Zhong Guo DENG Hui Bao LU (institute of Photographic Chemistry, Academia Sinica, Beijing, 100101)(china institute of {3. energy, Beijing, 102.13. ACAD SINICA INST PHOTOG CHEMBEIJING 100101PEOPLES R CHINA china INST ATOM energy BEIJING 102413PEOPLES R CHINA

Four kinds of phenol-formaldehyde resins containing benzo-15-crown-5 ether were synthesized for lithium isotope *** adsolptioncapacity and isotope effect of Liin these resins have been investigated. Singleseparation factors 1.023.1.056 were obtained with batch method from isotoperatios, 6Li and Li'were enriched in tile resin phase and liquid phase, respectively.

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PREPARATION,PROPERTIES AND INTERFACE STRUCTURES OF Si_3._(4w)/6061Al COMPOSITE

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Acta Metallurgica Sinica(English Letters) 1992年第11期5卷 423-428页

作者： PAN Jin Changsha institute of Technology,Changsha,chinaNING Xiaoguang YE Hengqiang Laboratory of atomic Imaging of Solids,institute of Metal Research,Academia Sinica,Shenyang,china Changsha Inst of Technology Changsha China

The Si_3._4 whisker reinforced 6061Al composite with bending strength of 790 MPa was prepared by squeeze casting *** heat-treatment under T6 regime i.e.53.℃, 1 h solutioning and 160℃,24 h aging,an increment in strength and microhardness may be over 20% and 28% respectively,The microstructures of Si_3._4 whisker and Si_3._4/Al interface were observed by meas of *** relation between interracial structure and composite properties was discussed.

关键词： β-Si_3._4 wthisker Al matrix composite strength interface

A land surface model incorporated with soil freeze/thaw and its application in GAME/Tibet

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Science china Earth Sciences 2006年第12期49卷 1311-1322页

作者： HU Heping1, YE Baisheng2, ZHOU Yuhua3.& TIAN Fuqiang1 1. Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, china 2. Cold and Arid Regions Environmental and Engineering Research institute, Chinese Academy of Sciences, Lanzhou 73.000, china 3. Department of Civil Engineering, Massachusetts institute of Technology, USA 1. Department of Hydraulic Engineering Tsinghua University Beijing 100084 China 2. Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou 730000 China 3. Department of Civil Engineering Massachusetts Institute of Technology USA

Land surface process is of great importance in global climate change, moisture and heat exchange in the interface of the earth and atmosphere, human impacts on the environment and eco- system, etc. Soil freeze/thaw plays an important role in cold land surface processes. In this work the diurnal freeze/thaw effects on energy partition in the context of GAME/Tibet are studied. A sophisti- cated land surface model is developed, the particular aspect of which is its physical consideration of soil freeze/thaw and vapor flux. The simultaneous water and heat transfer soil sub-model not only reflects the water flow from unfrozen zone to frozen fringe in freezing/thawing soil, but also demon- strates the change of moisture and temperature field induced by vapor flux from high temperature zone to low temperature zone, which makes the model applicable for various circumstances. The modified Picard numerical method is employed to help with the water balance and convergence of the numerical scheme. Finally, the model is applied to analyze the diurnal energy and water cycle char- acteristics over the Tibetan Plateau using the Game/Tibet datasets observed in May and July of 1998. Heat and energy transfer simulation shows that: (i) There exists a negative feedback mechanism between soil freeze/thaw and soil temperature/ground heat flux; (ii) during freezing period all three heat fluxes do not vary apparently, in spite of the fact that the negative soil temperature is higher than that not considering soil freeze; (iii) during thawing period, ground heat flux increases, and sensible heat flux decreases, but latent heat flux does not change much; and (iv) during freezing period, soil temperature decreases, though ground heat flux increases.

关键词： land surface model,soil freeze/thaw,GAME/Tibet,simultaneous liquid,vapor and heat transfer.

Ultrafast excitation relaxation in light-harvesting complex LH2 from *** 601

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Science china Chemistry 2004年第3期47卷 192-199页

作者： GUO Lijun1,2, LIU Yuan3. LIU Weimin2, GUO Junhua1, XU Chunhe3.& QIAN Shixiong2 1. School of Physics and Information Optoelectronics, Henan University, Kaifeng 475001, china 2. Physics Department, Fudan University, Shanghai 20043., china 3. Shanghai institute of Plant Physiology, Chinese Academy of Sciences, Shanghai 20003., china 1. School of Physics and Information Optoelectronics Henan University 475001 Kaifeng China 2. Physics Department Fudan University 200433 Shanghai China 3. Shanghai institute of Plant Physiology Chinese Academy of Sciences 200032 Shanghai China

The energy relaxation and kinetic evolution of transient spectra of bacteriochloro- phylls (BChls) in light-harvesting complex LH2 from Rb. sphaeroides 601 were investigated using femtosecond pump-probe technique. Upon 783.nm excitation, the energy at B800 BChls ex-periences an intramolecular redistribution with 0.3. ps time constant before transferring to B850 BChls. With tuning the excitation wavelength, the dynamical evolution of excited BChls was clearly observed, which indicates an obvious competition between the ground state bleaching and excited state absorption (ESA) of BChls involved and an isosbestic point near 818 nm, and also demonstrates that from the lower electronic excited state of B800 BChls to the higher exci-tonic state of B850 BChls is an efficient routine for energy transfer. The excitation energy in higher excitonic states of B850 BChls relaxes rapidly to the next lowest excitonic state by inter-conversion, delocalization to adjacent molecular, populating the lowest excitonic state and the change of molecular conformation.

关键词： photosynthesis, light-harvesting complex, energy transfer, ultrafast, dynamics, purple bacteria.

china-Russia energy Cooperation:Its Present Situation and Prospect

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和平与发展 2007年第3期 59-64页

作者： Xia Yishan (The author is a Senior Researcher at china institute of International Studies Director,china institute for energy Strategy Studies and Guest Researcher of CPDS.) china institute for energy Strategy Studies and Guest Researcher of CPDS

energy cooperation between china and Russia appears dissimilar to that between china and Kazakhstan and between china and the *** cooperation between china and Kazakhstan and between china and the Sudan takes the form that the Chinese corporations participate in the exploration and exploitation of local oil and gas resources,and gets back their shares the in oil and gas *** main form of energy cooperation between china and Russia,however,is that Russia exports oil and gas to china by way of *** order to

关键词： china-Russia energy Cooperation

Quantifying the effectiveness of SiO_2/Au light trapping nanoshells for thin film poly-Si solar cells

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Science china(Technological Sciences) 2010年第8期53卷 2228-2231页

作者： BAI YiMing 1 ,WANG Jun 2 ,CHEN NuoFu 1,3.,YAO JianXi 1 ,YIN ZhiGang 3.,ZHANG Han 3., ZHANG XingWang 3.,HUANG TianMao 3.,WANG YanShuo 3.&YANG XiaoLi 3.1School of Renewable energy Engineering,North china Electric Power University,Beijing 102206,china 2 National Engineering Research Center for Optoelectronic Devices,{3. of Semiconductors, Chinese Academy of Sciences,PO Box 912,Beijing 100083.china 3.Key Laboratory of Semiconductor Materials Science,{3. of Semiconductors, Chinese Academy of Sciences,PO Box 912,Beijing 100083.china 1. School of Renewable energy Engineering North China Electric Power University Beijing 102206 China2. National Engineering Research Center for Optoelectronic Devices Institute of Semiconductors Chinese Academy of Sciences PO Box 912 Beijing 100083 China3. Key Laboratory of Semiconductor Materials Science Institute of Semiconductors Chinese Academy of Sciences PO Box 912 Beijing 100083 China

In order to enhance light absorption of thin film poly-crystalline silicon(TF poly-Si)solar cells over a broad spectral range, and quantify the effectiveness of nanoshell light trapping structure over the full solar spectrum in theory,the effective photon trapping flux(EPTF)and effective photon trapping efficiency(EPTE)were firstly proposed by considering both the external quantum efficiency of TF poly-Si solar cell and scattering properties of light trapping *** EPTF,EPTE and scattering spectrum exhibit different behaviors depending on the geometric size and density of nanoshells that form the light trapping *** an optimum size and density of SiO2/Au nanoshell light trapping layer,the EPTE could reach up to 40%due to the enhancement of light trapping over a broad spectral range,especially from 500 to 800 nm.

关键词： thin film poly-crystalline silicon surface plasmons SiO2/Au nanoshell

Ancient Changjiang channel system in the East china Sea continental shelf during the last glaciation

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Science china Earth Sciences 2005年第11期48卷 1972-1978页

作者： LI Guangxue1,2, LIU Yong1, YANG Zigeng3. YUE Shuhong4, YANG Wenda5 & HAN Xibin1 1. College of Marine Geo-science, Ocean University of china, Qingdao 266003. china 2. Shandong Key Laboratory of Sea Floor Resource and Exploration Technique, Qingdao 266003. china 3. Qingdao {3. of Marine Geology, Qingdao 266071, china 4. College of Marine Environment, Ocean University of china, Qingdao 266003. china 5. First Survey Team of Marine Geology, Shanghai Bureau of Petroleum, Shanghai 201208, china 1. College of Marine Geo-science Ocean University of China 266003 Qingdao China 2. Shandong Key Laboratory of Sea Floor Resource and Exploration Technique 266003 Qingdao China 3. Qingdao institute of Marine Geology 266071 Qingdao China 4. College of Marine Environment Ocean University of China 266003 Qingdao China 5. First Survey Team of Marine Geology Shanghai Bureau of Petroleum 201208 Shanghai China

Based on the data of high-resolution seismic profiles, an ancient river channel sys-tem of the last glaciation occurred along the Zhedong and Xihu depression in the southeast of Hupijiao rise. The distribution of the channel fill system shows that the ancient Changjiang River went through the Changjiang depression into the low land plain of the outside continental shelf during the low sea level cycle of the last glaciation. The big channel fill into Okinawa Trough is not found due to the depletion of the river kinetic energy in the low land plain. The river discharge dispersal was of an important role to the dilution of the northern Okinawa Trough sea at that time. Six ancient river channel systems (A―F), which are main distributaries of ancient Changjiang in the East china Sea continental shelf during the last glaciation, may be buried off the modern Changjiang estuary. The distribution of these channels coincides with the zonal elevations in the sea floor.

关键词： last glaciation, continental shelf plain, Changjiang River, ancient channel fill

Theoretical Calculation of Neutron Cross Sections for 176Hf

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中国核科技报告 1997年第S2期 53-58页

作者： Huang Xiaolong Lu Hanlin (china institute of atomic {3., Beijing)

Neutron activation cross sections calculation forHf in the neutron energy below 20 MeV is carried out with UNF code. The calculated cross sections for (n,γ), (n,p), (n,α), (n,d), (n,t), (n,2n) and (n,3.) reaction are given. The results of the calculation are compared with the available experimental data and a good agreement is obtained. The calculation is also compared with the relevant evaluation data.

关键词： Theoretical Calculation of Neutron Cross Sections for Hf ENDF