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Superconductivity of small metal grains

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Science China(phys.cs,Mechanics & Astronomy) 2005年第4期48卷 431-441页

作者： ZHENG Renrong1 CHEN Zhiqian2.& ZHU Shunquan1,3 1. department of phys.cs, Shanghai {2. university, Shanghai 2.02.4, China 2. department of phys.cs, southwest normal university, chongqing 400715, China 3. department of Computer and Electric Technology, Shanghai Business School, Shanghai 2.1400, China 1. department of phys.cs Shanghai Normal University 200234 Shanghai China 2. department of phys.cs Southwest Normal University 400715 Chongqing China 3. department of Computer and Electric Technology Shanghai Business School 201400 Shanghai China

The formulas of the energy gap and superconducting critical temperature appropriate for systems with both odd and even number of electrons are derived; the bases of the derivations are Bcs theory and energy level statistics. Numerical results qualitatively agree with the experimental phenomena. i.e., the superconductivity of small metallic grains will first enhance then decrease to zero when the grain are getting smaller and smaller. The calculations indicate that the above phenomena happen in the metallic grains belonging to Gaussian Orthogonal Ensemble (GOE) and Gaussian Unitary ensemble (GUE) with zero spin; The superconductivity of small metallic grains in Gaussian Symplectic Ensemble (GSE) will monotonically decrease to zero with the decreasing of the grain size. The analyses suggest that the superconductivity enhancements come from pairing and the balance of the strengths between spin-orbital coupling and external magnetic field. In order to take the latter into account, it is necessary to include the level statistics given by Random Matrix Theory (RMT) in describing small metallic grains.

关键词： size effect, superconductivity enhancements, small metallic grains.

Resonance Rayleigh scattering study of the interaction of bleomycinA_5 with nucleic acids and its analytical application

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Science China Chemistry 2007年第5期50卷 629-637页

作者： LIU JiangTao1,2. LIU ZhongFang1 & LIU ShaoPu1 1 School of Chemistry and Chemical Engineering, southwest university,{2., China 2.department of Chemistry, Fuling normal university, chongqing 408000, China School of Chemistry and Chemical Engineering Southwest UniversityChongqing400715China department of Chemistry Fuling Normal UniversityChongqing 408000China

The interaction of bleomycinA5 with nucleic acids has been investigated byusing resonance Rayleigh scattering (RRS),molecular absorption and fluorescence *** resultshows that in near pH 2.2.buffer medium and absence of any metal ions,nucleic acids are capable ofbinding with bleomycinA5 (BLMA5) to form complexes which can remarkably enhance the RRS intensityand result in batho-chromic and hyperchromic molecular absorption of nucleic acids and fluorescencequenching of *** RRS spectral characteristics for the binding products of bleomycinA5with various DNA and RNA are similar,and the maximum RRS peaks are at 301 nm for ctDNA and sDNA,370nm for hsDNA,310 nm for RNAtypeVI and RNAtypelll,*** increments of RRS intensity aregreatly different in which DNA enhances greatly and RNA enhances *** this work,the optimumconditions of the interaction and some influencing factors have been *** reactionmechanism and a binding model for the interaction of BLMA5 with the nucleic acids are ***,a highly sensitive,simple and rapid new method for the determination of DNA has *** detection limits (3 sigma) are 5.7 ng/mL for ctDNA,7.4 ng/mL for sDNA and 9.2.ng/mLfor hsDNA,*** method can be applied to determination of trace amounts of DNA.

关键词： bleomycinA5, nucleic acids, resonance Rayleigh scattering, fluorescence quenching, absorption spectrum.

The joint limiting distribution of maxima with random indexes and sums of normal sequence

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西南师范大学学报（自然科学版） 1998年第5期23卷 1-6页

作者： Xie Shengrong department of Mathematics, southwest China {2. university, chongqing 400715

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Ｒｅｃｅｎｔｌｙ，ａｎｕｍｂｅｒｏｆｐａｐｅｒｓｈａｖｅｓｔｕｄｉｅｄｔｈｅｊｏｉｎｔａｓｙｍｐｔｏｔｉｃｉｎｄｅｐｅｎｄｅｎｔｐｒｏｐｅｒｔｉｅｓｏｆ∨ｎ１Ｘｉａｎｄｎ１Ｘｉｏｆｗｅａｋｌｙｄｅｐｅｎｄｅｎｔｓｔａｔｉｏｎａｒｙｓｅｑｕｅｎｃｅ｛...

关键词： joint limiting distribution maximum random index sum normal sequence

The influence of laser pulse on the photoabsorption spectra of Li atom in strong external field

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Science China(phys.cs,Mechanics & Astronomy) 2006年第2期49卷 178-186页

作者： WANG Dehua1 & LIN Shenglu2.1. School of phys.cs and Electronic Engineering, Yantai normal {2., Yantai 2.402., China 2. department of phys.cs, Shandong normal {2., Jinan 2.0014, China 1. School of phys.cs and Electronic Engineering Yantai Normal University Yantai 264025 China 2. department of phys.cs Shandong Normal University Jinan 250014 China

Using the time-dependent perturbation theory and the calculation formula of the single- and double-pulse absorption spectra of the atom in strong external fields, we calculate the single- and double-pulse absorption spectra of Li atom in strong magnetic field for different pulse widths. The results show that a pulse of some width can reduce the contribution of the short period closed orbits and eliminate the contribution of the long period orbits. Compared with the single-pulse absorption spectra, we found that for some phase differences, the double-pulse laser absorption spectra are strengthened; while for others, they are reduced. Therefore, we can use the pulse laser to control the oscillation of the absorption spectra and obtain the optimization object.

关键词： laser pulse closed orbit absorption spectra.

Fuzzy controllers based on some fuzzy implication operators and their response functions

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Progress in Natural Science:Materials International 2004年第1期14卷 16-21页

作者： LI Hongxing 1*, YOU Fei 1 and PENG Jiayin 2.1. department of Mathematics, Beijing normal {2., Beijing 100875, China 2. department of Mathematics, Neijiang Teacher's College, Neijiang 641112. China) Beijing normal Univ Dept Math Beijing 100875 Peoples R China

The fuzzy controllers constructed by 2. fuzzy implication operators based on CRI algorithm and their response functions are discussed. The conclusions show that the fuzzy controllers constructed by 9 fuzzy implication operators are universal approximators to continuous functions and can be used in practical fuzzy control systems. And these 9 fuzzy implication operators except for Einstein operator intersection are all the adjoint pairs of some fuzzy implication operators. Besides, there are 3 other fuzzy controllers formed by fuzzy implication operators being regarded approximately as fitted functions.

关键词： fuzzy implication operators CRI algorithm fuzzy controllers response functions universal approximators

Periodic Solutions for Second Order Systems at Resonance

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Acta Mathematica Sinica,English Series 1998年第4期14卷 433-440页

作者： Tang Chunlei, department of Mathematics, southwest normal university,{2., China department of Mathematics Southwest Normal University 400715 Chongqing China

The existence and multiplicity results are obtained for periodic solutions of second order systems at resonance with unbounded nonlinearity. The proofs rely on the minimax methods and an interesting integral inequality.

关键词： Periodic solution Resonance Critical point The (PS) condition The saddle point theorem The generalized mountain pass theorem

K-uniformly rotund spaces and k-uniformly smooth spaces

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Chinese Science Bulletin 1998年第2期43卷 92-95页

作者： Suyalatu 1 and WU Congxin 2.1. department of Mathematics,Inner Mongolia normal {2., Huhhot 01002., China 2. department of Mathematics, Harbin Institute of Technology, Harbin 150006, China department of Mathematics Inner Mongolia Normal University Huhhot China department of Mathematics Harbin Institute of Technology Harbin China

The conception of k_uniform smoothness (KUS) is introduced. It is the extension of the conception of uniform smoothness. It is proved that the k_uniform smoothness and Sullivan’s K_uniform rotundity (KUR) are the daul notions. X+* is a KUR space if and only if X is a KUS space, X+* is a KUS space if and only if X is a KUR space. If X is a KUS space, then X is a (K+1)US space. It is also proved that the KUS space includes the Nan’s k_strongly smooth space.

关键词： K_uniform smoothness K_uniform convexity.

A study of the optimal solution of a macroeconomics model

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西南师范大学学报(自然科学版) 1999年第5期24卷 519-525页

作者： Xiong Dasheng 1,Du Dongyao 2.1 department of Mathematics,southwest China {2. university,chongqing 400715 2.Financial Section,Sichuan Union university,Chengdu 610065 西南师范大学数学系重庆四川大学financial section 重庆

The optimal economic growth is always a main problem in economic control theory and it has been investigated by many scholars in their papers. A new sufficient condition of optimal control from a new angle is put forw... 详细信息

关键词： optimal economic growth optimal control sufficient condition trajectory

A hybrid approach of Knowledge Discovery in fishery resources evaluation

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西南师范大学学报(自然科学版) 1999年第5期 536-544页

作者： Li\ Li department of Computer Science,southwest China {2. university,chongqing 400715

A framework is put for ward,which integrates Knowledge Discovery in Database (KDD) with case based reasoning (CBR) and Bayesian *** following tasks are fulfilled:(1)discovering refined rules;(2.retrieving structured data which can not be described by flat vector feature;(3)forecasting the location of central fishing ground for the next *** these have been applied to a real case with some encouraging and interesting results.

关键词： knowledge discovery in databases bayesian network case based reasoning causal network