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THE THEOrETICAL STUDY OF ADSOrpTION OF METAL IONS ON CHITOSAN

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Chinese Journal of reactive polymers 2005年第Z1期 76-81页

作者： Lü renqing1 ZHANG Hongyu2 QIU Guangmin3 LIU Chenguang1 1 college of Chemistry and Chemical Engineering, china university of petroleum (East china), Dongying 257061, china 2 Environmental Sanitation Office, Municipal Administration, Yantai Economic and Technological Developmental Zone, Yantai 264000, china 3 college of petroleum Engineering, china university of petroleum (East china), Dongying 257061, china

The interactions between metal ions such as Zn2+, pb2+, Mn2+, Hg2+, Cd2+, Ni2+ and chitosan have been investigated using the model cluster model method and density functional method. Full optimization and frequency analysis of all cluster models have been performed employing B3LYp hybrid method at 3-21G basis set level except metal ions which were invoked to use effective core potential (ECp) method. The energy changes, and the main structural parameters have been obtained during the theoretical study of the adsorption of metal ions on the chitosan. The calculations showed that the coordination modes of metal ions with chitosan models were different, the geometries of Mn2+, Zn2+, Cd2+, Hg2+, pb2+ ions coordinated with two nitrogen atoms and two oxygen atoms were distorted tetrahedral, while the square planar structure of Ni2+ coordinated two nitrogen atoms and two oxygen atoms was observed. The heat of reaction between six metal ions and chitosan models showed the order: Mn2+ >Ni2+ >Zn2+ >pb2+ >Hg2+ >Cd2+, this suggested that the coordination strength of Mn2+ >Ni2+ >Zn2+ >pb2+ >Hg2+ >Cd2+.

关键词： Density functional theory Basis set Effective core potential Chitosan, Metal ions.

Mechanistic aspects of oxidation of palladium with O2

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中国科学:化学 2012年第10期42卷 1490-1490页

作者： JIN LiQun & LEI AiWen* college of Chemistry and Molecular sciences,Wuhan university,Wuhan 430072,china college of Chemistry and Molecular sciences Wuhan university Wuhan 430072 china

palladium-catalyzed aerobic transformation has been one of the most challenging topics within organometallics ***,the corresponding methodology has been developed rapidly,involving alcohol oxidation,alkene oxidation,oxidative coupling and so on,which stimulated considerable interests in mechanistic investigation of the oxidation of pd with *** review summarizes most of the mechanistic studies on this topic during the past ten ***,the future of the mechanistic investigation for aerobic oxidation of pd is also discussed.

关键词： palladium O2 mechanism

The evolution of cooperation in asymmetric systems

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Science china(life sciences) 2010年第1期53卷 139-149页

作者： WANG ruiWu1 & SHI Lei2 1 State Key Laboratory of Genetic resources and Evolution,Kunming Institute of Zoology,Chinese Academy of Science,Kunming 650223,china 2 Statistics and Mathematics college,Yunnan university of Finance and Economics,Kunming 650221,china 1. State Key Laboratory of Genetic resources and Evolution Kunming Institute of Zoology Chinese Academy of Science Kunming 650223 China2. Statistics and Mathematics College Yunnan University of Finance and Economics Kunming 650221 China

Explaining the "Tragedy of the Commons" of the evolution of cooperation remains one of the greatest problems for both biology and social *** interaction,which is one of the most important characteristics of cooperative systems,has not been sufficiently considered in the existing models of the evolution of *** the inequality in the number and payoff between the cooperative actors and recipients in cooperation systems,discriminative density-dependent interference competition will occur in limited dispersal *** model and simulation show that the local but not the global stability of a cooperative interaction can be maintained if the utilization of common resource remains unsaturated,which can be achieved by density-dependent restraint or competition among the cooperative *** intense density dependent interference competition among the cooperative actors and the ready availability of the common resource,with a higher intrinsic contribution ratio of a cooperative actor to the recipient,will increase the probability of *** cooperation between the recipient and the cooperative actors can be transformed into conflict and,it oscillates chaotically with variations of the affecting factors under different environmental or ecological *** higher initial relatedness(*** to kin or reciprocity relatedness),which is equivalent to intrinsic contribution ratio of a cooperative actor to the recipient,can be selected for by penalizing less cooperative or cheating actors but rewarding cooperative individuals in asymmetric *** initial relatedness is a pivot but not the aim of evolution of *** explains well the direct conflict observed in almost all cooperative systems.

关键词： cooperation altruism density dependent tragedy of the commons oscillation chaos asymmetric interaction interference competition

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Delay-Dependent passivity Analysis for Delayed Neural Networks with Markovian Jumping parameters

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Delay-Dependent Passivity Analysis for Delayed Neural Networ...

第三十届中国控制会议

作者： LI Yongmin~(1,2),FEI Shumin~2,XIA Jianwei~2,CHU Yuming~1 1.School of Science,Huzhou Teachers college,Huzhou 313000,p.r.china 2.School of Automation,Southeast university,Nanjing 210096,p.r.china

＜正＞This paper deals with the problems of passivity analysis for a class of delayed neural networks whith Markovian jumping *** delay-dependent passivity critira conditions for the neural networks concerned are obtained by using a mode-dependent Lyapunov functional and introducing some slack *** conditions are expressed by means of linear matrix inequalities（LMIs） which are easy to *** from lierature[27],the time-varying delay interval is more general and the uncertainties are Markovian form,thus covers the system studied in[27]as a special case.

关键词： Delay-dependent Conditions Markovian Jumping parameters passivity Time-varying Delays

Effects of growth-promoting factors on long-term proliferation of mouse spermatogonial stem cells(SSCs)

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Effects of growth-promoting factors on long-term proliferati...

中国畜牧兽医学会动物繁殖学分会第十五届学术研讨会

作者： Zhi-Guo Fan~1,rui-Kai Lv~1,Jian-Hong Hu~1,Zhong-Liang Jiang~1, Qing-Wang Li~(1,2),Yu Liu~1,Jin-Xin Mo~1,Zhe Qiang~1 1 college of Animal Science and Technology,Northwest A & F university,Yangling,Shaanxi 712100,p.r.china 2 college of Environment and Chemistry Engineering,Yanshan university,Qinhuangdao,Hebei 066004,p.r.china

To investigate the influence of growth-promoting factors,including EGF,IGF-1 and FGF,on the proliferation of mouse SSCs,21 kinds of culture methods,including single factor groups,double factors combinations and triple factors combinations,were designed to culture SSCs ***,the results were significantly *** the third passage of mouse SSCs was cultured for 4 days,the highest percentage of SSCs proliferation was 40.30%, yet the lowest level was 11.20%(pr groups,the highest percentage of SSCs proliferation was 61.50%,yet the lowest level was 37.51%(p rs combinations,the highest percentage of SSCs proliferation was 56.53%,yet the lowest level was 39.72%(p riple factors *** these data,we can find that single factor EGF(lOng/ml) was able to promote distinctly the SSCs proliferation,whereas the double factors EGF(20ng/ml),IGF-1(20ng/ml) combinations and the triple factors EGF(20ng/ml),IGF-1(20ng/ml), FGF(1Ong/ml) combinations were optimal combinations *** confirm that moderate single factor and the proportionate appropriately multi-factors combinations can promote abundantly the SSCs proliferation in vitro.

关键词： Spermatogonial stem cells proliferation EGF IGF-1 FGF

Habitat selection by territorial male ring-necked pheasants: a synthetic analysis

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Habitat selection by territorial male Ring-necked Pheasants:...

23rd International Ornithological Congress

作者： Ni Xijun Zheng Guangmei and Zhang ZhengwangInstitute of Vertebrate paleontology and paleoanthropology, Chinese Academy of sciences, Beijing, 100044 Ministry Key Laboratory for Biodiversity Science and Ecological Engineering, college of life sciences, Beijing Normal university,Beijing 100875, china

＜正＞ recent research reveals that breeding male ring-necked pheasants （phasianus colchicus） tend to select habitats that are mixed, establishing their territories where patches of several types of habitat meet. Traditional analyses dealt with such preferences by addressing selectivity for each habitat type separately. Our research emphasizes the need for a more interactive approach. Areas where several habitat patches mesh may be termed habitat complexes;pheasant selectivity for such complexes is the outcome of historic adaptation to modern

关键词： habitat complex. ring-necked pheasant habitat selectivity territory.

Assessment model of dam operation risk based on monitoring data

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Science china(Technological sciences) 2007年第z1期50卷 144-152页

作者： WU Zhongru1,2?, SU HuaiZhi1,2 & GUO HaiQing1 1 college of Water Conservancy and Hydropower Engineering, Hohai university, Nanjing 210098, china 2 National Engineering research Center of Water resources Efficient Utilization and Engineering Safety, Nanjing 210098, china 1. college of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China 2. National Engineering research Center of Water resources Efficient Utilization and Engineering Safety Nanjing 210098 China

Although the dams produce remarkable social and economic benefits, the threat made by unsafe dams to the life and property of people who live in the lower river area is un-negligible. Based on the monitoring data which reflect the safety condition of dams, the risk degree concept is proposed and the analysis system and model for evaluating risk degree (rate) are established in this paper by combining the reliability theory and field monitoring data. The analysis method for risk degree is presented based on Bayesian approach. A five-grade risk degree system for dam operation risk and corresponding risk degree is put forward according to the safety condition of dams. The operation risks of four cascade dams on some river are analyzed by the model and approach presented here and the result is adopted by the owner.

关键词： dam monitoring data operation risk degree analysis model

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A self-calibration algorithm for cross array in the presence of mutual coupling

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Science china(Information sciences) 2011年第4期54卷 836-848页

作者： HU XiaoQin 1,2,CHEN Hui 2,WANG YongLiang 2 & CHEN JianWen 2 1 college of Electronic Science and Engineering,National university of Defense Technology,Changsha 410073,china 2 Key Lab of Wuhan radar Academy,Wuhan 430019,china 1. college of Electronic Science and Engineering National University of Defense Technology Changsha 410073 China2. Key Lab of Wuhan Radar Academy Wuhan 430019 China

In this paper,a novel blind mutual coupling self-calibration algorithm especially tailored to cross array is *** method compensates for the mutual coupling not only between sensors in each subarray but also between two *** the property of coupling matrix,the proposed method requires neither the calibration sources in known locations nor the multidimensional nonlinear *** method can jointly estimate the DOAs of the incoming signals and the unknown mutual coupling coefficients,and has high estimation precision and low computational *** analysis and computer simulations show the effectiveness of the proposed algorithm.

关键词： cross array mutual coupling self-calibration DOA estimation

New results for Globally Asymptotic Stability and Instability of recurrent Neural Networks

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New Results for Globally Asymptotic Stability and Instabilit...

第二十六届中国控制会议

作者： Zhang Yutian1,Luo Qi2 1.college of Mathematics and physics,Nanjing university of Information Science and Technology,Nanjing 210044,p.r.china2.college of Information and Control,Nanjing university of Information Science and Technology,Nanjing 210044,p.r.china

This paper presents four new theorems of globally asymptotic stability and instability for a general class of continuous- time recurrent neural networks with variant *** weaker conditions and less restrictive activation function,the obtained stability results improve and extend existing *** and examples are given to illustrate and compare the new results with the old ones.

关键词： Globally Asymptotic Stability recurrent Neural Networks Instability