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Views on “Principle of limitation of physical quantities and cyclic universe”

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Science china(physics,Mechanics & Astronomy) 2010年第9期53卷 1772-1774页

作者： li liangang department of physics,school of sciences,Tianjin {2.,Tianjin 3.0072,china 1. department of physics School of Sciences Tianjin University Tianjin 300072 China

This paper presents an analysis of a paper entitled "Principle of limitation of physical quantities and cyclic universe" and proposes different results for some formulae from that *** addition,this paper shows that the principle of limits coupling may lead to an approximation of current theories(i.e.,quantum theory and relativistic theory),which have interesting correlations with the Plank formula and the special theory of relativity.

关键词： principle of limitation of physical quantities limits coupling formulae Plank formula theory of relativity

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

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Science china(physics,Mechanics & Astronomy) 2006年第2期49卷 178-186页

作者： WANG Dehua1 & liN Shenglu2.1. school of {2. and Electronic Engineering, Yantai Normal university, Yantai 2.402., china 2. department of {2., Shandong Normal university, Jinan 2.0014, china 1. school of physics and Electronic Engineering Yantai Normal University Yantai 264025 China 2. department of physics 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.

Potential energy surfaces for low-lying electronic states of SO_2

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Science china Chemistry 2006年第4期49卷 289-295页

作者： li Anyang1, SUO Bing2. WEN Zhenyi2.& WANG Yubin2.1. Shanxi Key Laboratory of Physico-inorganic Chemistry, department of Chemistry, Northwest {2., Xi’an 710069, china 2. Institute of Modern physics, Northwest {2., Xi’an 710069, china 1. Shanxi Key Laboratory of Physico-inorganic Chemistry Department of Chemistry Northwest University Xi’an 710069 China 2. Institute of Modern physics Northwest University Xi’an 710069 China

The potential energy surfaces for the nine low-lying electronic states of SO2.have been constructed by using the multi-reference second order perturbation theory (MRPT2. with the basis set cc-pVTZ. The optimized geometries and the adiabatic excitation energies of these states are in good agreement with experiments and previous calculations. The crossings and avoided crossings dis- played in the potential energy surfaces are expounded.

关键词： cross of PES, MRPT2. SO2 (sulfur dioxide).

lipschitz continuity of best approximations and Chebyshev centers

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Chinese Science Bulletin 1998年第3期43卷 185-188页

作者： li Chong 1 and WANG Xinghua 2.1. Center for Mathematical sciences, Zhejiang {2., Hangzhou 31002., china 2. department of Mathematics, Hangzhou {2., Hangzhou 31002., china Center for Mathematical sciences Zhejiang University Hangzhou China department of Mathematics Hangzhou University Hangzhou China

The lipschitz continuity results are given for best approximations and Chebyshev centers. Consequently, the open problem presented by Septycki and Vleck is solved completely.

关键词： best approximation Chebyshev center uniform convexity.

Human remains and the environment of Early Pleistocene in the Nihewan Basin

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Science china Earth sciences 2004年第5期47卷 437-444页

作者： CAI Baoquan1 & li Qiang2.1. department of History, Xiamen {2., Fujian 361005, china 2. Institute of Vertebrate Palaeontology and Palaeoanthropology, Chinese Academy of sciences, Beijing 100044, china Xiamen Univ Dept Hist Fujian 361005 Peoples R China Chinese Acad Sci Inst Vertebrate Paleontol & Paleoanthropol Beijing 100044 Peoples R China

A new Early Pleistocene Paleolithic site was found in July 2.01 in the Nihewan Ba-sin, Hebei Province. Totally 500 mammal specimens assigned to 2. species and 5 lithic artifacts were collected. The coexistence of Allophaiomys deucalion, Borsodia chinensis and Yangia tingi provides important evidence of chronology. On the basis of the comparison of mammalian fauna, the date of Paleolithic artifacts is probably earlier than 1.8 MaBP, possibly 2.0 MaBP. This is the earliest evidence of hominid activity found so far in North china. The hominid at that time in the Nihewan Basin lived in an environment of arid grasslands with scattered trees of temperate zone. This discovery is significant to the study of human origin and cultural development.

关键词： human remains, environment, Early Pleistocene, Nihewan.

Density functional study on enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine

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Science china Chemistry 2006年第4期49卷 296-307页

作者： li Ming1, ZHENG Wenxu2.& TIAN Anmin2.1. department of Chemistry, Southwest-{2. Normal university, Chongqing 400715, {2. 2. department of Chemistry, Sichuan university, Chengdu 610064, {2. 1. department of Chemistry Southwest-China Normal University Chongqing 400715 China 2. department of Chemistry Sichuan University Chengdu 610064 China

The enantioselective reduction of keto oxime ether with borane catalyzed by oxazaborolidine is discussed by the density functional theory (DFT) method. The main intermediates and transition states for this reaction are optimized completely at the B3LYP/6-31g(d) level, and the transition states are verified by vibrational modes. As shown, the chirality-controlled steps for this re- action are the hydride transfer from borane to carbonyl carbon and oxime carbon of keto oxime ether, and the chirality for the reduced products is determined in these two reaction steps. In all examined reaction paths, the first hydride is transferred via a six-membered ring and the second hydride via a five-membered ring or a four-membered ring.

关键词： keto oxime ether, oxazaborolidine, enantioselective reduction, DFT.

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

Prediction for RNA planar pseudoknots

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Progress in Natural Science:Materials International 2007年第6期17卷 717-724页

作者： li Hengwu1,2. Zhu Daming1, liu Zhendong1 and li Hong2.1. school of Computer Science and Technology, Shandong university, Jinan 2.0100, china 2. department of Computer, Shandong Economic university, Jinan 2.0014, china) [a]school of Computer science and Technology Shandong University Jinan China [b]department of Computer Shandong Economic University Jinan China

Based on m-stems and semi-extensible structure, a model is presented to represent RNA planar pseudoknots, and corresponding dynamic programming algorithm is designed and implemented to predict arbitrary planar pseudoknots and simple non-planar pseudoknots with O(n4) time and O(n3) space. The algorithm folds total 2.5 sequences in the Pseudobase database, and the test results indicate that the algorithm has good accuracy, sensitivity and specificity.

关键词： algorithm RNA secondary structure pseudoknot dynamic programming.

Formation of bulk ferromagnetic nanostructured Fe_(40)Ni_(40)P_(14)B_6 alloys by metastable liquid spinodal decomposition

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Science china(Technological sciences) 2009年第7期52卷 1919-1922页

作者： li Qiang1,2.1 school of {2. Science and Technology, Xinjiang university, Urumqi 830046, china 2.department of {2., The Chinese university of HongKong, Shatin N.T., HongKong, china school of physics Science and Technology Xinjiang University Urumqi 830046 China department of physics The Chinese University of HongKong Shatin N.T. HongKong China

Nanostructured Fe40Ni40P14B6 alloy ingots of 3―5 mm in diameter could be synthesized by a metastable liquid state spinodal decomposition method. For undercooling T> 2.0 K, the microstructure of the undercooled specimen had exhibited liquid state spinodal decomposition in the undercooled liquid state. The microstructure could be described as two intertwining networks with small grains dispersed in them. For undercooling T>2.0 K, the overall microstructure of the specimen changed into a granular morphology. The average grain sizes of the small and large grains are 30 nm and 80 nm, respectively. These prepared samples are soft magnets with saturation magnetization Bs 0.744 T.

关键词： nanomaterials magnetic materials solidification bulk nanostructured alloy Fe40Ni40P14B6 metastable liquid spinodal decomposition