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Nitrogen content features of several indigenous evergreen and decidous tree species in chongqing region

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西南师范大学学报(自然科学版) 1999年第5期24卷 586-593页

作者： Zeng\ Bo School of Life Science,southwest China normal University,{2. {3. 西南师范大学重庆

To aid to reveal the basic physiological differences existing between evergreen and deciduous plants, so as to facilitate our understanding of relationships between physiological features of evergreen & deciduous plants and their corresponding growth and biomass production, nitrogen content patterns of four indigenous tree species in chongqing region including evergreen and deciduous plants growing in optimal conditions were analyzed. It is shown that leaf nitrogen content of deciduous tree species was significantly higher than that of evergreen tree species. Based on this result, it can be inferred that researched evergreen and deciduous tree species had basic differences in their leaf nitrogen content. There were no significant differences appeared between studied evergreen and deciduous tree species on nitrogen content of branches and stems. Compared with branch and stem, leaves had highest nitrogen content unexceptionally for all researched plants regardless of species. Nitrogen content of stems decreased with the age of stem for all investigated evergreen and deciduous species.

关键词： evergreen deciduous tree species nitrogen content chongqing

Fredholm operators in Toeplitz algebras associated with discrete abelian groups

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Chinese Science Bulletin 1998年第14期43卷 1175-1179页

作者： XU Qingxiang 1 and CHEN Xiaoman 2.1. department of Mathematics, Shanghai normal University, Shanghai 2.02.4, China 2. Laboratory of Mathematics for Nonlinear Sciences and Institute of Mathematics, Fudan University, Shanghai 2.043., China department of Mathematics Shanghai Normal University Shanghai China Laboratory of Mathematics for Nonlinear Sciences and Institute of Mathematics Fudan University Shanghai China

The locally finite below sets are introduced and the Fredholm operators in Toeplitz algebras associated with discrete abelian groups are studied.

关键词： discrete abelian group quasi_ordered group Toeplitz operator Fredholm operator.

THz spectrum of reduced glutathione

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Science China(physics,Mechanics & Astronomy) 2005年第5期48卷 585-592页

作者： WANG Weining1, YAN Haitao1, YUE Weiwei1, ZHAO Guozhong1, ZHANG Cunlin1, LIU Haibo2.& ZHANG Xicheng2.1. department of {3., Capital {2. University, Beijing 10003., China 2. Center for Terahertz Research, Rensselaer Polytechnic Institute, Tory, NY, USA 1. department of physics Capital Normal Univesity 100037 Beijing China 2. Center for Terahertz Research Rensselaer Polytechnic Institute Tory NY USA

The optical characteristics of reduced glutathione molecules between 0.2.THz and 2.4 THz have been investigated by THz time-domain spectroscopy (THz-TDS). The absorption characteristics and optical parameters of the reduced glutathione purged with Nitrogen at room temperature were obtained experimentally. The measured results were fitted well with the theoretical results computed by using Density Functional Theory (DFT) in far-infrared range. Also the conformation of the reduced glutathione molecule was simulated by Gaussian 03. This work has demonstrated significantly that THz-TDS spectroscopy can further be used to study other biological molecules in biological and biomedical engineering.

关键词： THz time domain spectroscopy, reduced glutathione, absorption spectrum, biological engineering.

An equality on Hochschild homology groups

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Chinese Science Bulletin 1997年第8期42卷 624-627页

作者： ZHANG Pu and LIU Shaoxue1. department of Mathematics, University of Science and Technology of China, Hefei 2.002., China 2. department of Mathematics, Beijing {2. University, Beijing 100875, China department of Mathematics University of Science and Technology of China Hefei China department of Mathematics Beijing Normal University Beijing China

LET A be finite-dimensional algebra over field k,and Ae the enveloping algebra of A,i.e.Ae=A kAop,where Aop is the opposite algebra of *** A-bimodule has a natural left Ae-module structure as follows:

关键词： finite-dimensional algebra Hochschild homology groups dimensions.

Variations in the content of zeatin during tuber development of sweet potato and Ipomoea trifida

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西南师范大学学报(自然科学版) 1999年第5期 576-580页

作者： Zhang Qitang 1,Fu Yufan 1,Xiong Fengqi 2.Yuan Lüjiang 2.1 chongqing Sweet Potato Scientific Research Center,{3. China {2. University,chongqing 400715 2.Central Laboratory,{3. China Agricultural University,chongqing 400716

The contents of zeatin in different tuberous roots and fibrous roots of sweet potato and Ipomoea trifida at several periods of growth were determined by applying high performance liquid chromatography(HPLC).The results are as follows:After being planted for 60 days,90 days or 12. days,the contents of zeatin in 3.～70 g,and 100～2.0 g tuberous root of sweet potato are distinctly higher than those in *** and fibrous roots of sweet potato of 0 2.0 5 cm in diameter during the same period of *** during the three periods of growth mentioned above,the content of zeatin in fibrous roots of sweet potato is indistinctly different from that of *** .A comparison of the content of zeatin during development shows that,the content of zeatin after being planted 12. days is remarkably higher than that of zeatin after being planted for 60 days and 90 days, but the difference between those being planted for 60 days and 90 days is not distinct.

关键词： sweet potato Ipomoea trifida zeatin HPLC

袁家军胡衡华王炯程丽华会见出席2.2.重庆国际友好城市合作大会重要嘉宾

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重庆与世界 2024年第5期 16-19页

作者： chongqing Daily 重庆日报

5月2.日上午，市委书记袁家军，市委副书记、市长胡衡华，市人大常委会主任王炯，市政协主席程丽华会见了来渝出席2.2.重庆国际友好城市合作大会的3.个国家48个城市的重要嘉宾。老挝占巴塞省省委书记兼省长阿伦赛·顺那拉，白俄罗斯明...

5月2.日上午，市委书记袁家军，市委副书记、市长胡衡华，市人大常委会主任王炯，市政协主席程丽华会见了来渝出席2.2.重庆国际友好城市合作大会的3.个国家48个城市的重要嘉宾。老挝占巴塞省省委书记兼省长阿伦赛·顺那拉，白俄罗斯明斯克州执行委员会主席图尔钦·亚历山大，

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OPTIMIZATION OF ADAPTIVE DIRECT METHOD FOR APPROXIMATE SOLUTION OF INTEGRAL EQUATIONS OF SEVERAL VARIABLES

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Acta Mathematica Scientia 2004年第2期24卷 228-234页

作者：马万房艮孙 departmentofMathematics BeijingNormalUniversityBeijing100875China

This paper determines the exact error order on optimization of adaptive direct methods of approximate solution of the class of Fredholm integral equations of the second kind with kernel belonging to the anisotropic So... 详细信息

关键词： Integral equations direct methods anisotropic sobolev classes

Theoretical study on S_1(~1B_(3.)) state electronic structure and absorption spectrum of pyrazine

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Science China Chemistry 2008年第12期51卷 1166-1173页

作者： HE RongXing1, ZHU ChaoYuan 2. CHIN Chih-Hao3.& LIN Sheng-Hsien2.3.1 College of Chemistry and Chemical Engineering, southwest University,{3., China 2.{2. of Applied Chemistry, Institute of Molecular Science and Center for Interdisciplinary Molecular Science, National Chiao-Tung University, Hsinchu 3.0, China 3.Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, China 1. College of Chemistry and Chemical Engineering Southwest University Chongqing 400715 China 2. department of Applied Chemistry Institute of Molecular Science and Center for Interdisciplinary Molecular Science National Chiao-Tung University Hsinchu 300 China 3. Institute of Atomic and Molecular Sciences Academia Sinica Taipei 106 China

Making use of a set of quantum chemistry methods, the harmonic potential surfaces of the ground state (S0(1Ag)) and the first (S1(1B3.)) excited state of pyrazine are investigated, and the electronic structures of the two states are characterized. In the present study, the conventional quantum mechanical method, taking account of the Born-Oppenheimer adiabatic approximation, is adopted to simulate the absorp-tion spectrum of S1(1B3.) state of pyrazine. The assignment of main vibronic transitions is made for S1(1B3.) state. It is found that the spectral profile is mainly described by the Franck-Condon progression of totally symmetric mode ν6a. For the five totally symmetric modes, the present calculations show that the frequency differences between the ground and the S1(1B3.) state are small. Therefore the displaced harmonic oscillator approximation along with Franck-Condon transition is used to simulate S1(1B3.) absorption spectra. The distortion effect due to the so-called quadratic coupling is demonstrated to be unimportant for the absorption spectrum, except the coupling mode ν10a. The calculated S1(1B3.) ab-sorption spectrum is in reasonable agreement with the experimental spectra.

关键词： pyrazine absorption spectrum quantum mechanical method electronic structure

Near infrared lights emission of ^(40)Ar^(16+) impacting on metal surfaces

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Science China(physics,Mechanics & Astronomy) 2009年第7期52卷 1021-1026页

作者： ZHANG XiaoAn1,2. XIAO GuoQing2. YANG ZhiHu2. WANG Li1 & ZHAN WenLong2.1 department of physics, Xianyang {2. University, Xianyang 712.00, China 2.Institute of Modern physics, Chinese Academy of Sciences, Lanzhou 73.000, China department of physics Xianyang Normal University Xianyang 712000 China Institute of Modern physics Chinese Academy of Sciences Lanzhou 730000 China

The highly charged ion 40Ar16+ with the velocity (kinetic energy EK=150 keV, velocity V=8.5×105 m/s) smaller than Bohr velocity (VBohr=2.9×106 m/s) was found to hove impacts on the surfaces of metals Ni, Mo, Au and Al, and the Ar atomic infrared light lines and X-rays spectra were simultaneously measured. The experimental results show that the highly charged ion that captures electrons is neutralized, and the multiply-excited hollow atom forms. The hollow atom cascade decay radiates lights from infrared to X-ray spectrum. The intensity of infrared lights shows that the metallic work functions play an important role in the neutralization process of highly charged ions during their interaction with metallic surfaces, which verifies the classical over-the-barrier model.

关键词： infrared light lines X-ray neutralization highly charged ions