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Ab Initio MO Studies on the Reaction Mechanism for Carbonyl Insertion Catalyzed by Carbonyl Cobalt Complex

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Chemical Research in Chinese Universities 2000年第1期16卷 31-35页

作者： LEI Ming FENG Wen-lin and XU Zhen-feng (Department of applied Chemistry, beijing University of Chemical Technology,beijing {3., P. R. china Department of Chemistry, beijing Normal University, beijing 100875, P. R. china) beijing Univ Chem Technol Dept Appl Chem Beijing 100029 Peoples R China beijing Normal Univ Dept Chem Beijing 100875 Peoples R China

Ab initio method, under the effective core potential(ECP) approximation at HF/LANL2DZ level, has been employed to study the reaction mechanism of the carbonyl insertion of olefin hydroformylation catalyzed by a carbonyl cobalt HCo(CO)_3. The two reaction paths have been discussed. The calculated potential energy barriers for the carbonyl migration and the ethyl group migration are 105. 0 kJ/mol and 3.. 17 kJ/mol, respectively. The results indicate that the reaction path via ethyl migration is more energetically favorable than that via carbonyl insertion.

关键词： Carbonyl Cobalt Hydroformylation Ab initio method Effective core potential

Combinatorial Invariants on Planar Graphs

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Acta Mathematica Sinica,English Series 1995年第2期11卷 211-220页

作者： Liu Yanpei institute of applied Mathematics Academia Sinica beijing, 100080{3. institute of applied Mathematics Academia Sinica Beijing People's Republic of China

This paper introduces three kinds of operators on planar graphs with binary weights on edges, for which combinatorial invariants on two kinds of equivalences are found. Further, it is shown that the Jones polynomial and the bracket polynomial which are proved to be new topological invariants on knots in topology become special cases. Moreover, these invariants are a kind of generalization of Tutte polynomial on graphs.

关键词： link Combinatorial Invariants on Planar Graphs

THE EXISTENCE OF J-HOLOMORPHIC CURVES AND APPLICATIONS TO THE WEINSTEIN CONJECTURE

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Chinese Annals of Mathematics,Series B 1999年第4期20卷 425-434页

作者： MA RENYI(Department of applied Mathmatics, Tsinghua University, beijing 100084, china) Tsinghua Univ Dept Appl Math Beijing 100084 Peoples R China

The author first proves the existences of J-holomorphic curves in the symplectizations of Legendre fibrations and then as an application confirms the Weinstein conjectures on contact manifolds of Legendre fibrations. As a corollary a new proof on the theorem due to Hofer,Viterbo, Gluck, Ziller, Weinstein and Ljusternik-Fet Theorem is provided, which is quite different from their original proofs.

关键词： Symplectic geometry J-holomorphic curves Periodic orbit

Response synchronization: New progress in brain-visual information processing

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Chinese Science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry , institute of Atmospheric Physics , Chinese Academy of Sciences , beijing 100029, china 2. Commission of the National Natural Science Foundation of china , beijing 100083. china 3. The Center of Information Science , Peking University, beijing 100871, china 4. Open Laboratory of Visual Information Processing , institute of Biophysics , Chinese Academy of Sciences , beijing 100101, china State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National Natural Science Foundation of china Beijing China The Center of Information Science Peking University Beijing China Open Laboratory of Visual Information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. Naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

Absolute radiometric calibration of CBERS-02 IRMSS thermal band

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Science china(Technological Sciences) 2005年第S2期48卷 72-90页

作者： ZHANG Yong1,2,3. GU Xingfa1,3.4, YU Tao1,3. ZHANG Yuxiang5, CHEN Liangfu1,3. LI Xiaoying1,2,3. LI Xiaowen1,3.& HE Liming6 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the institute of Remote Sensing Applications of Chinese Academy of Sciences and beijing Normal University, beijing 100101,{3. 2. Graduate University of Chinese Academy of Sciences, beijing 10003.,{3. 3. The Center for National Spaceborne Demonstration, beijing 100101,{3. 4. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 5. National Satellite Meteorological Center, beijing 100081,{3. 6. State Environmental Protection Administration, beijing 100029,{3. Chinese Acad Sci Inst Remote Sensing Applicat State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China beijing Normal Univ State Key Lab Remote Sensing Sci Beijing 100101 Peoples R China Chinese Acad Sci Grad Univ Beijing 100039 Peoples R China Ctr Natl Spaceborne Demonstrat Beijing 100101 Peoples R China INRA F-84914 Avignon France Natl Satellite Meteorol Ctr Beijing 100081 Peoples R China State Environm Protect Adm Beijing 100029 Peoples R China

Based on the laboratory calibration before launch of CBERS-02 IRMSS thermal infrared channel, the onboard blackbody calibration, the radiometric cross- calibration against TERRA MODIS corresponding channel and the in-flight field calibration at Lake Qinghai: water surface radiometric calibration test site of china on Aug. 17, 2004 are carried out in this research. When making onboard blackbody calibration of CBERS-02 IRMSS, it is necessary to understand inside structures and light path in IRMSS camera and receive and process calibration blackbody signals at normal and high temperatures. Onboard blackbody calibration results of each detector are very important to relative radiometric calibration of images processing and absolute radiometric calibration of each detector. In-flight field calibration mainly contains field experiments, obtaining synchronous images, spectrum marching and MODTRAN radiative transmi- ssion computation. Radiometric cross-calibration of CBERS-02 IRMSS thermal band against TERRA MODIS selected 6 times synchronous images of two sensors passing through Lake Qinghai and Lake Taihu from August to December, 2004 to compute the cross calibration data. Combining the in-flight field calibration and radiometric cross calibration data, the absolute radiometric calibration coefficients are calculated by the linear regression method. This new calibration model can obviously control the radiometric calibration uncertainties aroused by the single point method used in the in-flight calibration of CBERS-02 IRMSS, this kind of sensors cannot receive the cosmic background radiation. In this research, the radiometric calibration coefficients obtained through the linear regression model are 8.53.(gain, unit: DN/W m?2sr?1μm?1) and 44.92 (offset, unit: DN).

关键词： CBERS-02 IRMSS thermal band in-flight field calibration onboard blackbody calibration cross calibration.

Information content security on the Internet:the control model and its evaluation

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Science china(Information Sciences) 2010年第1期53卷 30-49页

作者： FANG BinXing1, GUO YunChuan2,3.& ZHOU Yuan4 1School of Computer, beijing University of Posts and Telecommunications, beijing 100029, china 2{3. of Computing Technology, Chinese Academy of Sciences, beijing 100190, china 3.raduate University of Chinese Academy of Sciences, beijing 100049, china 4National Computer Network Emergency Response Technical Team/Coordination Center of china, beijing 100029, china 1. School of Computer Beijing University of Posts and Telecommunications Beijing 100029 China2. Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China3. Graduate University of Chinese Academy of Sciences Beijing 100049 China4. National Computer Network Emergency Response Technical Team/Coordination Center of China Beijing 100029 China

Flooding of harmful information on the Internet seriously endangers the physiological and mental health of teenagers. Due to the user-friendliness of the Internet as well as the difficulty in the authentication for the access of specific categories of information, curbing the transmission of harmful information, i.e., assuring the information content security (ICS), has become a reasonable yet challenging alternative. At present, there is an urgent need to develop a systematic model that can effectively carry out the curbing. In fact, curbing the transmission of harmful information by way of filtering can be modeled by access control. In the paper, based on the three core-elements of communication, namely, "Who communicates with whom", "How do they communicate" and "What is the content of communication", we propose a control model, called ICCON. Unlike the existing access control, the reference monitor (RM) of our model is placed in the transmission channel, and moreover, an evaluation frame is proposed, through which the effectiveness of the RM in controlling information transmission on the Internet can be quantitatively evaluated.

关键词： content security access control quantitative evaluation

The PNA wavetrain and the sea surface temperature in the Northern Pacific

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Acta Oceanologica Sinica 1990年第4期9卷 527-538页

作者： Lin Xuechun institute of Synoptic and Dynamic meteorology, Academy of Meteorological Science, SMA, beijing,{3. Inst. of Synoptic & Dynamic meteorology Academy of Meteorological Science SMA Beijing China.

In this paper, the response of the atmospheric 3.5 year cycle to Northern Pacific SST is discussed, The results are as follows:1. From the simultaneous temporal correlations between the Equatorial Eastern Pacific SST, the westerly dirft area's SST and the Northern Pacific SST at all gridpoints, we find that there are three correlative regions in the Northern Pacific SST field, they are the westerly drift area, the Equatorial Eastern Pacific and the Alaska Bay , and their structures are very similar to the PNA pattern in the atmosphere The difference PTI between the Equatorial Eastern Pacific SST anomaly and the westerly drift area's SST anomaly can indicate the change of the PNA pattern of the Northern Pacific SST anomaly. It can represent SST change of 65 % areas over the Northern Pacific and can keep watch on El Nino and un-El Nino.2. Simultaneous temporal correlative field between PTI and filtered 500hPa (there is 3.5 year cycle only ) of the Northern Hemisphere presents clear PNA structure. The responses of the filtered 500hPa to El Nino and to un-EI Nino produce +PNA and -PNA wavetrains respectively.3. According to the different positions of the sea-surface temperature rise (drop) ,El Nino (un-EI Nino )can be divided into two classes: east-pattern and middle-pattern. The responses of the filtered 500hPa to the east-pattern and to the middle-pattern will produce PNA and EAA wavetrain respectively. This indicates that the responses of the atmosphere to the stationary heat sources in diffrent areas will produce wavetrains in diffrent track.

关键词： Nino EI The PNA wavetrain and the sea surface temperature in the Northern Pacific SST PNA

2002:The extra-strong warm winter event in North Asia and its accompanying anomalous atmospheric circulation

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Chinese Science Bulletin 2003年第10期48卷 1031-1033页

作者： WANG Huijun LASG, institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, china LASG Institute of Atmospheric Physics Chinese Academy of Science China

Features of an extra-strong warm winter event in North Asia in 2002 and its accompanying anomalous atmospheric circulation were studied through diagnosis on the atmospheric reanalysis data set. Results show that the winter of 2002 is of the warmest in the recent 54 years in North Asia, which was caused by both decadal scale and interannual scale variability. The interannual variability is proved to be as the main cause for the event, and it is related to the global scale atmospheric circulation anomalies, with the strongest of them in the Eastern Hemisphere and in the middle and high latitude region of the Southern Hemisphere.

关键词：大气环流亚洲北部高强度暖冬现象天气资料

Dissipative Transitions between Bloch Bands

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Journal of Materials Science & Technology 1999年第4期15卷 363-365页

作者： Xangeng ZHAO(institute of applied Physics and Computational Mathematics, beijing 100088,{3.)E-mail:zhaoxg@*** Inst Appl Phys & Computat Math Beijing 100088 Peoples R China

We study the effect of dissipative transport of two-band systems in a static electric field. With the help of numerical solutions of a stochastic Liouville equation for the density matrix, we find that the Markoffian dephasing will take electrons which are initially located in one band to equal population of the two bands, instead of undergoing Zener resonance, as they do in the absence of scattering.

关键词： Rev Dissipative Transitions between Bloch Bands