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Microwave-assisted reaction of peptide formation by amino acid with phosphate:Exploration of the most possible channels for the origin of life

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Science china Chemistry 2006年第4期49卷 351-356页

作者： HU Rong1, TIAN Jinping2.& YIN Yingwu2.3 1. College of Chemistry & Environment Protection Engineering, Southwest University for Nationalities, chengdu 610041, china 2. TH-UNIS Insight Co., Ltd., Beijing 100085, china 3. Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical biology, Ministry of Education, department of Chemistry, Tsinghua University, Beijing 100084, china 1. College of Chemistry & Environment Protection Engineering Southwest University for Nationalities Chengdu 610041 China 2. TH-UNIS Insight Co. Ltd. Beijing 100085 China 3. Key Laboratory of Bioorganic Phosphorus Chemistry & Chemical biology Ministry of Education Department of Chemistry Tsinghua University Beijing 100084 China

Microwave-assisted reaction of peptide formation by amino acids with phosphate was studied. The results showed that the products were a mixture of peptides containing dipeptide, oc- tapeptides and cyclic peptides, which could be obtained in a short time. Polyphosphate was also produced synchronously by the intermolecular condensation of phosphate. The polymerization de- gree reached 99% (pyrophosphate 64%, trimetaphosphate 35%) after 2.h at 2.0℃ under microwave irradiation. The intermediates of the mixed anhydrides formed by the intermolecular condensation of phosphates and glycin were determined by ESI-MS. Peptides were also produced by the reaction of amino acids with trimetaphosphate in aqueous solution. The conversion degree of valine reached 46.5% even at room temperature. The cyclic process of peptide formation and phosphate polymeri- zation, regeneration and utilization in amino acids-phosphate system under microwave irradiation was detected and proved. Peptides could be continually formed only by inputting energy into this system. The above recycle may be the most possible process for primitive peptide formation in the origin of life.

关键词： microwave, phosphate, amino acid, peptide, origin of life.

Additive characters and orthogonal systems of polynomials in several indeterminates over residue class rings

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Chinese Science Bulletin 1998年第4期43卷 275-277页

作者： HONG Shaofang department of Mathematics, Sichuan University, chengdu 610064,{2. department of Matherrratics Sichuan University Chcngdu China

Let m, n and k be positive integers, m>1 and k≤n . Let Z m =Z/ m Z denote the residue class ring modulo m . Let Z denote the group of additive characters of ring Z m , x 0 denote the identity of Z . A necessary and sufficient condition for the system f\-1, ..., f\-k∈ Z m [ x\-1, ..., x\-n ] to be orthogonal is given: for all additive characters ψ 1, ..., ψ k ∈Z with ψ i≠x 0 for some i, 1≤i≤k, ∑(c\-1, ..., c\-n)∈ Z n m ψ(f\-1(c\-1, ..., c\-n))...ψ k(f\-k(c\-1, ..., c\-n))=0. As corollaries, the result of Shiue_Sun_Zhang and the result of Sun are obtained.

关键词： orthogonal system additive character permutation polynomial Jacobi matrix.

A Method for Obtaining Three-dimensional Images with Visual Reality of Real Objects

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Chinese Journal of Lasers 1999年第5期8卷 425-430页

作者： HUANG Qiong SU Xianyu(department of Opto-electronics, Sichuan University, chengdu 610064,{2.) 四川大学光电子系四川成都 610064 四川大学光电子系四川成都

A new method to remove the shadows in laser triangulation and a computer model for three-dimensional images with visual reality of three-dimensional diffuse objects are presented. The methods for acquiring color data in optical three-dimensional sensing are discussed A method for obtaining three-dimensional images with visual reality of real objects is presented The principles, the system structure and the experimental results are provided.

关键词： three-dimensional sensing laser triangulation shadow three-dimensional images with visual reality

Magnetic mineralogy of the Hongqiling Cu-Ni sulphide deposit: Implications for ore genesis

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Progress in Natural Science:Materials International 2007年第10期17卷 1192-1198页

作者： Xi Aihua1,2. Ge Yuhui1, Cai Yuanfeng2.and Zhang Xuefeng3(1. Faculty of Resources & Environment, Southwest Petroleum University, chengdu 610500, china 2. State Key Laboratory for Endogenic Metal Deposit Research, Nanjing University, Nanjing 2.0093, china 3. department of Natural Resources & Technology Information, china University of Petroleum, Beijing 102.49, china) Faculty of Resources & Environment Southwest Petroleum University Chengdu 610500 China State Key Laboratory for Endogenic Metal Deposit Research Nanjing University Nanjing 210093 China department of Natural Resources & Technology Information China University of Petroleum Beijing 102249 China

Pyrrhotite is one of the common ore minerals in Cu-Ni sulphide deposits, but only monoclinic pyrrhotite is ferromagnetic at room temperature. X-ray and EPA analyses reveal that most pyrrhotite forming sideronitic texture in the Hongqiling Cu-Ni sulphide deposit is monoclinic, but that in the massive ore is a mixture of monoclinic and hexagonal pyrrhotites. Differential thermal and magnetic- thermogravimetric analyses of massive ore indicate a magnetic transition and heat absorption at 32.℃, suggesting that this temperature is the thermomagnetic and phase transition point of pyrrhotite. For massive pyrrhotite ores heated at 400oC for 30 h and then quenched by cool water, the monoclinic pyrrhotite (mpo) transforms completely into the hexagonal pyrrhotite (hpo). However, all the pyrrhotites resulting from slow cooling of the sample in air are mpo. These results indicate that transformation between hpo and mpo depends upon the cooling rate. Therefore, massive ores in this deposit might have been formed via rapid cooling of ore melts. On the other hand, it is significant to study the effect of the ratio of the magnetite in total ores on the genesis of magmatic Cu-Ni suphide deposits.

关键词： pyrrhotite magnetite genesis of Cu-Ni sulphide deposit Hongqiling.

Diffusion Equation on Fractals:Three-Dimensional Case

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Communications in Nonlinear Science and Numerical Simulation 1999年第3期4卷 3-5页

作者： Qiuhua ZENG and Houqiang LI(department of Physics, Sichuan University, chengdu 610064,{2.) department of Physics Sichuan University ChengDu 610064 China

IntroductionInrecentyearsthephenomenonofunusualtrajnsport-prop***onindisorderedmediaorfractalmedia,anomalousdiffusionistheoretic... 详细信息

IntroductionInrecentyearsthephenomenonofunusualtrajnsport-prop***onindisorderedmediaorfractalmedia,anomalousdiffusionistheoretic...

关键词： comb model probability density diffusion on fractals

Accurate studies on the full vibrational energy spectra and molecular dissociation energies for some electronic states of N_(2.molecule

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Science china(Physics,Mechanics & Astronomy) 2005年第4期48卷 385-398页

作者： REN Weiyi1,2. SUN Weiguo1, HOU Shilin3 & FENG Hao4 1. Institute of Physics, College of Chemical Engineering, Sichuan University, chengdu 610065, china 2. Institute of Theoretical Physics, Xihua Normal University, Nanchong 637002. china 3. department of Physics, china Oceanography University, Qingdao 2.6003, china 4. College of Physics, Sichuan University, chengdu 610065, china 1. Institute of Physics College of Chemical Engineering Sichuan University 610065 Chengdu China 2. Institute of Theoretical Physics Xihua Normal University 637002 Nanchong China 3. department of Physics China Oceanography University 266003 Qingdao China 4. College of Physics Sichuan University 610065 Chengdu China

It is usually very difficult to directly obtain molecular dissociation energy De and all accurate high-lying vibrational energies for most diatomic electronic states using modern experimental techniques or quantum theories, and it is also very difficult to give accurate analytical expression for diatomic molecular dissociation energy. This study proposes a new analytical formula for obtaining accurate molecular dissociation energy based on the LeRoy and Bernstein’s energy expression in dissociation limit. A set of full vibrational energy spectra for some electronic states of N2.molecule are studied using the algebraic method (AM) suggested recently, and the corresponding accurate molecular dissociation energies are evaluated using the proposed new formula and high-lying AM vibrational energies. The results show that the AM spectra and the new theoretical dissociation energies agree excellently with experimental data, and thereby providing a new physical approach to generating accurate dissociation energies for electronic states of diatomic molecules.

关键词： vibrational energy, dissociation energy, nitrogen molecule, algebraic method.

Anomalous Fractional Diffusion Equation forTransport Phenomena

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Communications in Nonlinear Science and Numerical Simulation 1999年第2期4卷 99-104页

作者： Qiuhua ZENG Houqiang LI De LIU(department of Physics, Sichuan University, chengdu 610064,{2.) department of Physics Sichuan University ChengDu 610064 China

We derive the standard diffusion equation from the continuity equationand by discussing the defectiveness of earlier proposed equations, we get the generalizedfractional diffusion equation for anomalous diffusion.

关键词： fractal lattice probability density fractal anomalous diffusion

Monitoring the Cultivated Slope Land in the Three Gorges Reservoir Area Based on Remote Sensing and GIS

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Wuhan University Journal of Natural Sciences 2006年第4期11卷 915-921页

作者： ZHOU Jieming1, ZHOU Qigang 2. 3 ,HUANG Zhiqin 2. 3, 4 1. The Faculty of Geography and Resources Science, Sichuan Normal University, chengdu 610066, Sichuan, china 2. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, chengdu 610041, Sichuan, china 3. Graduate University of the Chinese Academy of Sciences, Beijing 100049, china 4. Information Center of Land and Resources department of Sichuan Province, chengdu 610041, Sichuan, china The Faculty of Geography Resources Science Sichuan Normal University 610066 Chengdu Sichuan China Institute of Mountain Hazards Environment Chinese Academy of Sciences 610041 Chengdu Sichuan China Graduate University of the Chinese Academy of Sciences 100049 Beijing China Information Center of Land Resources department of Sichuan Province 610041 Chengdu Sichuan China

By means of combining auto-extraction with manual interpretation, the current distribution information about cultivated land is obtained. The distribution information of 1992.is extracted from the dynamic polygons of 2.02. The monitoring mini-system of the cultivated slope land is established. In the system, detailed surveys, focused on the resources of cultivated slope land, are carried out. The results indicate that the area of the cultivated slope land is very large. Meanwhile, there are lots of cultivated steep slopes with gradient above 35°. The areas of steep land cultivated had been slowly reduced from 1992.to 2.02. At the same time, the pressures of returning farm land to forestry are great in all counties. The conflicts between population growth, insufficient grain supply and stagnant economic development sharpen increasingly. It is inevitable to improve the agricultural structure.

关键词： slope land cultivated remote sensing geography information system (GIS) the pressure of returning farm land to forestry Three Gorges Reservoir Area

Origin and controlling factors of chlorite coatings—an example from the reservoir of T_3x Group of the Baojie area,Sichuan Basin,china

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Petroleum Science 2009年第4期6卷 376-382页

作者： Peng Jun1,Liu Jinku2.Wang Yan2.and Liu Jianfeng2.1 Scientific Research department,Southwest Petroleum University,chengdu,Sichuan 610500,{2. 2.Graduate School,Southwest Petroleum University,chengdu,Sichuan 610500,{2. Scientific Research department Southwest Petroleum University Chengdu Sichuan China Graduate School Southwest Petroleum University Chengdu Sichuan China

The study of the chlorite coatings always attracts scholars in china and other countries because the chlorite coatings play an important role in the preservation of residual primary pores in sandstone *** present,the study of the origin and the controlling factors is relatively *** occurrence,time of formation,genesis,controlling factors,and the mechanism of chlorite coatings inhibiting quartz overgrowths were studied in detail with thin section and SEM *** were from the sandstone reservoirs of the T3x Group in the Baojie area,the transitional zone from the middle to the south of Sichuan *** results indicate that the chlorite coatings on the walls of the pore spaces are oriented perpendicular to grain surfaces in the form of isopachous(even-thickness) grain-coating,while the chlorite coatings at the contacts between adjacent detrital grains are arranged with a preferred orientation tangential to the surface of detrital *** chlorite coatings were formed in the eogenetic *** were formed by recrystallization of Fe-rich clay films during the syndepositional period,and chlorite cements would be recrystallized after the coatings’ *** formation of chlorite coatings was mainly controlled by the depositional environment,provenance conditions,and diagenetic *** presence of chlorite coatings could result in the preservation of primary pores in deeply buried sandstone reservoirs by effectively inhibiting quartz overgrowths and the development of compaction and pressure solution.

关键词： Chlorite coatings occurrence time of formation origin controlling factor quartz overgrowths T3x Group