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Particle tunnels across the horizon of Garfinkle-Horowitz-Strominger dilaton black hole

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Science china(Physics,Mechanics & Astronomy) 2007年第5期50卷 601-610页

作者： FANG HengZhong1 & ZHAO Zheng2.1 department of Physics, china {2. of Petroleum, Dongying 2.7061, china 2.department of Physics, Beijing normal {2., Beijing 100875, china department of Physics China University of Petroleum Dongying China department of Physics Beijing Normal University Beijing China

We promote the work of Parikh and Wilczek on the black hole radiation to the emission of massive and charged particles from Garfinkle-Horowitz-Strominger black hole. The energy and charge of the space-time are conservational during the course of the evaporation. The calculation shows that the emission spectrum is not precisely thermal, while has a correction, and the conclusion supports the view- point of information conservation.

关键词： Hawking radiation, black body spectrum, barrier, information loss, entropy of black hole, Komar energy

Taxonomic circumscription of Sinojackia xylocarpa (Styracaceae)

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Journal of Systematics and Evolution 2011年第2期49卷 163-164页

作者： 1 Li-Qun LUO 2.Chi LUO 1 (department of Chemistry and Life Science, Leshan normal {2., Leshan 614004, china) 2.(department of Mathematics, Leshan normal {2., Leshan 614004, china) (department of Chemistry and Life Science Leshan Normal University Leshan 614004 China) (department of Mathematics Leshan Normal University Leshan 614004 China)

Sinojackia xylocarpa Hu in Journ. Arn. Arb. 9: 130. 192.. Type: china. Jiangsu: Nanjing, Y. L. Keng 1376 (PE!). Sinojackia rehderiana Hu in Journ. Arn. Arb. 11: 2.7. 1930, syn. nov. Type: china. Jiangxi: Nanchang, H. ... 详细信息

关键词： PE Styracaceae Taxonomic circumscription of Sinojackia xylocarpa

CONVERGENCE IN THE CHEMOSTAT MODELWITH DELAYED RESPONSE IN GROWTH

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Systems Science and Mathematical Sciences 1999年第1期12卷 23-32页

作者： WANG Wendi (department of Mathematics, southwest normal university,{2., china)MA Zhien (department of Mathematics, Xi’an Jiaotong university, Xi’an 710049, china) 西南师范大学数学系重庆西安交通大学数学系陕西西安

The asymptotic behavior of solutions of a model for competition between two microorganisms in the chemostat is studied. The model incorporates time delays that allow for cellular components of each competing species to be structured to include unassimilated or stored nutrient and allow uptake functions to be nonmonotone. By introducing two auxiliary functions and using fluctuation lemma, it is shown that at most one competitor survives, and the substrate and the surviving competitor (if one exists), approach limiting values. Our results indicate this kind of time delays do not influence the competitive outcome except for a critical case. The main results of S. F. Ellermeyer[1] are improved on and extended.

关键词： Chemostat competition time delays global dynamics.

Studies on the developmental biology of sweet potato seed

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西南师范大学学报(自然科学版) 1999年第5期24卷 571-575页

作者： Li Kunpei 1,Sun\ Min 1,Yan Yinhong 2.1 School of Life Science,southwest normal {2.,chongqing 400715 2.chongqing Institute of Crop,chongqing 402.60 西南师范大学重庆重庆市作物所重庆

The developmental biology of ovule,embryo and seed of sweetpotato was *** development of sweet potato seed started anthesis fertilization and zygote *** was formed through morphorological changes of ovule in different *** shape and weight of seed related to the number of seed in each capsule related to the development or abortion of *** organic substance of seed consisted of protein,carbohydrate,fat,and accumulated with the days increasing after pollination.

关键词： sweet potato seed developmental biology

Formation and Evolution of Ancient Lakes on South Coast Plain of Laizhou Bay

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Chinese Journal of Population,Resources and Environment 2005年第4期3卷 26-32页

作者： Han Mei 1, Zhou Baohua 2. Yang Peilin 1,Gao Guiqin 1 & Zhang Weiying 1 1. department of Geography, Shandong normal {2., Jinan 2.0014, china 2. department of Geography, Jinan {2., Jinan 2.0001, china department of Geography Shandong Normal University Jinan 250014 China department of Geography Jlnan University Jinan 250001 China

Based on the data of historical geography, the analysis of the stratigraphic section, and the textual research of place names and satellite photographic interpretations, the authors study the formation and evolution of ancient lakes on the south coast plain of Laizhou Bay where there were once three lakes: Judian Lake, Qingshuibo Lake and Biehua Lake. All the lakes formed 6000 years ago evolved from the lagoons near the estuary and went through two periods, the golden age in the Middle Holocene and the shrinking age in the Late Holocene. The disappearance of the lakes resulted from the drying climate, the migration of the river courses and the activities of human beings. Among the three reasons, the migration of the river courses is the main one.

关键词： ancient lake cause historical evolution south coast plain of Laizhou Bay

The optical near-field speckles and their first order statistics on the basis of the integral equations of electromagnetic field

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Science china(Physics,Mechanics & Astronomy) 2004年第3期47卷 365-380页

作者： CHENG Chuanfu1, 2. SONG Hongsheng2. LIU Chunxiang2. REN Xiaorong2. ZHANG Ningyu3, TENG Shuyun1 & XU Zhizhan1 1. Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P. O. Box 800-2.1, Shanghai 2.1800, china 2. department of Physics, Shandong {2. university, Jinan 2.0014, china 3. Shandong Institute of Architecture and Engineering, Jinan 2.0014, china Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaichina department of PhysicsShandong normal {2.Jinanchina Shandong Institute of Architecture and EngineeringJinanchina

From Helmholtz equation of the harmonic electromagnetic waves, the integral equations of the light field at the medium boundaries are obtained by use of the Green's theorem and are discretized into linear equation set with the values of the light field and its derivative as the unknowns. On solving the linear equation set, we realize the rigorous computations of the light fields at the boundaries. Then the intensities of the light waves scattered by the random self-affine fractal surfaces in the optical near-field are calculated, and the propagation characteristics, the evolutions of the contrast and the intensity probability density function of the near-field speckles are studied in detail. The near-field speckles are much different from the conventional speckles in the diffraction regions and in the imaging systems. There are obvious local fluctuations in the intensity distributions of the near-field speckles and such fluctuations disappear after propagating a distance of one wavelength from the medium surfaces. For the random surfaces with smaller lateral correlation lengths, the speckle contrasts approach the saturation values and the speckle fields approach Gaussian distribution within the near-field, while for the random surfaces with larger lateral correlation lengths, such evolutions become comparatively slow.

关键词： speckle, near-field optics, first order statistics, Green's function.

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,{2. 2. State Key Laboratory for Endogenic Metal Deposit Research, Nanjing university, Nanjing 2.0093,{2. 3. department of Natural Resources & Technology Information,{2. university of Petroleum, Beijing 102.49,{2.) 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 Infor- mation 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.

An oscillatory neural network and dynamical associative memory

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西南师范大学学报（自然科学版） 1998年第5期23卷 38-43页

作者： Feng Jiuchao,male,33 years old,associate professor. Feng Jiuchao 1,Zhou Shu 2.1 department of physics,southwest{2. normal university,chongqing 400715 2.South{2. university of Technology,Guangzhou 510641

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关键词： neural network dynamical associative memory synchronous oscillation

Quasirational dynamic system

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Chinese Science Bulletin 2000年第14期45卷 1277-1279页

作者： SUN Daochun & YANG Lo1. department of Mathematics, South china {2. university, Guangzhou 510631, china 2. Institute of Mathematics, Academy of Mathematics and System Sciences, Chinese Academy of Sciences, Beijing 100080, china department of Mathematics South China Normal University Guangzhou China Institute of Mathematics Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing China

Using the iterations of quasirational mappings, the theorems on dynamic system are generalized to the quasirational dynamic system. Some different results are also obtained.

关键词： quasirational mapping dynamic system covering surface.