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Weighted weak type estimates for commutators of the Marcinkiewicz integrals

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science China Mathematics 2004年第1期47卷 83-95页

作者： DING Yong, LU Shanzhen & ZHANG PuDepartment of Mathematics, beijing normal university, beijing 100875, China Department of Information and Computing {2., Zhejiang {3. of {2. and Technology, Hangzhou 3.003., China 1. Department of Mathematics Beijing Normal University 100875 Beijing China 2. Department of Information and Computing science Zhejiang Institute of Science and Technology 310033 Hangzhou China

In this paper the authors give the weighted weak LlogL type estimates for a class of the higher order commutator generated by the Marcinkiewicz integral and a BMO function. In addition, the weak type norm inequalities... 详细信息

关键词： Marcinkiewicz integral, commutator, Ap weight, weak type estimate.

On the stability of diffusion processes with state-dependent switching

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science China Mathematics 2006年第9期49卷 1258-1274页

作者： XI Fubao & ZHAO Liqin Department of Mathematics, beijing institute of Technology, beijing 100081, China School of Mathematical {3.s, beijing normal university, beijing 100875, China Department of Mathematics Beijing Institute of Technology Beijing 100081 China School of Mathematical sciences Beijing Normal University Beijing 100875 China

In this paper we consider the stability for diffusion processes with state-dependent switching. We first prove their Feller continuity by the coupling methods. Furthermore, we also prove their strong Feller continuity and their exponential ergodicity under some reasonable conditions. Finally, we append a very brief discussion about the regularity of these processes.

关键词： Feller continuity, coupling, strong Feller continuity, exponential ergodicity,state-dependent switching.

The information entropy of a static dilaton black hole

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science China(Physics,Mechanics & Astronomy) 2008年第2期51卷 113-125页

作者： LIU ChengZhou institute of Theoretical Physics, Binzhou university, Binzhou 2.6600, China Department of Physics,{2.,{3., China 1. institute of Theoretical Physics Binzhou University Binzhou 256600 China 2. Department of Physics Beijing Normal University Beijing 100875 China

In accordance with holographic principle, by calculating the statistical entropy of the quantum field just at the event horizon of the Garfinkle-Horowitz-Strominger dilaton black hole, the information entropy of the black hole was investigated and the Bekenstein-Hawking formula was obtained. The results show that black hole entropy is identical with the statistical entropy of the quantum field at the horizon. Using the generalized uncertainty relation, the divergence of the state density near the event horizon in usual quantum field theory was removed, and the cutoffs and the little mass approximation in the heat gas method of black hole entropy were avoided. Thus, the microstates of the massive scalar field just at the event horizon of the static dilaton black hole were studied directly and a description on holograph principle was presented. By using residue theorem, the integral difficulty in the calculation was overcome, and the information entropy and the Bekenstein-Hawking formula were obtained quantitatively. Compared with the black hole entropy from the loop quantum gravity, the consistency of methods and results of calculating black hole entropy in non-commutative quantum field theory and loop quantum gravity was investigated. By this, the gravity correction constant in the generalized uncertainty relation was suggested and the sense of holographic principle was discussed.

关键词： black hole entropy holographic principle non-commutative quantum field theory event horizon loop quantum gravity

Refraction of light in media

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science China(Physics,Mechanics & Astronomy) 2007年第5期50卷 591-600页

作者： ZHANG Tao Key Laboratory of Beam Technology and Material Modification of Ministry of Education, institute of Low Energy Nuclear Physics, beijing normal university,{2., China {3. Radiation Center,{2., China Key Laboratory of Beam Technology Material Modification of Ministry of Education Institute of Low Energy Nuclear Physics Beijing Normal University Beijing 100875 China beijing Radiation Center Beijing 100875 China

The roles of the magnetic field and electric field of the light are investigated when the light is refracted in the medium. The model of the electron cloud conductor is presented. Electron cloud in a molecule is treated as a conductor and the Faraday’s Law is applied to this conductor that is in the alternating magnetic field of the light. dBM/dt of the light gives rise to an alternating induced current on the electron cloud conductor, and the light exchanges energy, i.e. the refractive energy, with the elec- tron cloud conductor. Formulas of refractive index, which is the ratio of light speed in vacuum to that in the medium, are derived with this model. These formulas are tested with several mediums and Langevin’s diamagnetic susceptibility of helium gas, and the results are in good agreement with the measured data. The anisotropy and the nonlinearity of the refractive index are explained with the theory described in this work.

关键词： refractive index, light, speed, medium, propagation

Evidence from carbon isotope measurements for biological origins of individual long-chain n-alkanes in sediments from the Nansha Sea,China

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Chinese science Bulletin 2002年第7期47卷 578-581页

作者： DUAN Yi & WANG ZhipingState Key Laboratory of Gas Geochemistry, Lanzhou institute of Geology, Chinese Academy of sciences, Lanzhou 73.000, China institute of {3. science, beijing normal university, beijing 100875, China 1. State Key Laboratory of Gas Geochemistry Lanzhou Institute of Geology Chinese Academy of Sciences 730000 Lanzhou China 2. institute of environmental science Beijing Normal University 100875 Beijing China

Carbon isotopes are measured for individual long-chain n-alkanes in sediments from the Nansha Sea. The features of carbon isotopic compositions of individual n-alkanes and their origins are studied. The results show that the long-chain n-alkanes have a light carbon isotopic composition and a genetic feature of mixing sources, and low-latitude higher plants and microbes are considered to be their main end member sources. Based on the abundances and carbon isotopic compositions of individual n-alkanes, the fractional contributions of the two end member sources to individual n-alkanes are quantitatively calculated by using a mixing model. The obtained data indicate that the fractional contributions of the two biological sources are different in the three samples. A trend is that the contribution of microbes increases with the depth. These results provide the theory basis and quantitatively studied method for carbon isotopic applied research of individual n-alkanes.

关键词： modern marine sediment individual n-alkane carbon isotopic composition biological source.

The formation and stability of Si_(1-x)C_x alloys in Si implanted with carbon ions

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Chinese science Bulletin 2001年第3期46卷 200-204页

作者： WANG Yinshu, LI Jinmin, JIN Yunfan, WANG Yutian, SUN Guosheng & LIN Lanying1. Department of Physics, beijing normal university, beijing 100875, China 2. {2. of Semiconductors, Chinese Academy of {3.s, beijing 100083. China 3. {2. of Modern Physics, Chinese Academy of {3.s, Lanzhou 73.000, China Department of Physics Beijing Normal University Beijing China institute of Semiconductors Chinese Academy of Sciences Beijing China institute of Modern Physics Chinese Academy of Sciences Lanzhou China

Si1-xCx alloys of carbon (C) concentration between 0.6%-1.0% were grown in Si by ion implantation and high temperature annealing. The formation of Si1-xCx alloys under different ion doses and their stability during annealing were studied. If the implanted dose was less than that for amorphizing Si crystals, the implanted C atoms would like to combine with defects produced during implantation and it was difficult to form Si1-xCx alloys after being annealed at 850℃. With the increment of implanted C ion doses, the lattice damage increased and it was easier to form Si1-xCx alloys. But the lattice strain would become saturate and only part of implanted carbon atoms would occupy the substitutional positions to form Si1-xCx alloys as the implanted carbon dose increased to a certain degree. Once Si1-xCx alloys were formed, they were stable at 950℃, but part of their strain would release as the annealing temperature increased to 1 000℃. Stability of the alloys became worse with the increment of carbon

关键词： ion implantation Si1-xCx alloys stability of Si1-xCx alloys.

Study on Water Consumption Coefficient of People's Living and Its Regional Disparity in the North of China

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Chinese Journal of Population,Resources and Environment 2005年第2期3卷 20-26页

作者： Wang Jing’ai 1-3. Mao Rui 3.4, Yang Mingchuan 3.4 & Zhou Junju 11 College of Geography & Remote Sensing 2.Key Laboratory of Regional Geography of beijing normal university 3.Key Laboratory of environmental Change and Natural Disaster of Ministry of Education of China 4 College of Resources {2. & Technology, beijing normal university, beijing 100875, China College of Geography and Remote Sensing Beijing 100048 China Key Laboratory of environmental Change and Natural Disaster of Ministry of Education of China Beijing 100048 China College of Resources science and Technology Beijing Normal University Beijing 100875 China

By employing the information-reshufflingmethod that integrates census data, precipitation dataand inquiry data of water consumption, this paperdiscusses 5 (water consumption coefficient of people’sliving) in allusion to different precipitation zones anddifferent periods of time. The study shows that 5-(water consumption coefficient of urban people’sliving), 5. (water consumption coefficient of ruralpeople’s living) and increase with time passing, andthe increasing extent of 5 is 1.84, 2.62. 2.84 and 2.68times respectively from the west to the east, whichresults from the total quantity of water resources andthe speed of urbanization. 5- and 5. of eachprecipitation zone increased with 5- increasing morequickly than 5., and the difference between the twoalso increased when time passed. In the past fifty years(1950-2.00), the increasing extent of 5- was 1.71,2.96, 2.41 and 2.3. times respectively from the westto the east, in which 2.0-400mm precipitation zoneincreased more than others. Meanwhile the increasingextent of 5. is 1.55, 1.60, 1.53.and 1.64 timesrespectively from the west to the east with eachprecipitation zone increasing similarly. The change of5-is due to the speed of urbanization and the stabilityof water resources. This study provides basis forcalculating the water demand of people’s living andrevealing the impact of water demand of people’s livingon ecological drought in different zones.

关键词： The north of China precipitation zone water consumption coefficient of people’s living

Relation between seed size in different plant species and response of their seedlings to double CO_2

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Chinese science Bulletin 1997年第4期42卷 331-333页

作者： DING Li, ZHANG Chonghao, BAI Kezhi and KUANG Tingyun1 Department of Biology, beijing normal university, beijing 100875, China 2. {2. of Botany, Chinese Academy of {3.s, beijing 100093. China Department of Biology Beijing Normal University Beijing China institute of Botany Chinese Academy of Sciences Beijing China

ATMOSPHERIC CO2.concentration is predicted to increase to 700μL/L by the middle of the 2.st century. The impacts of raising CO2.on vegetation and ecosystem have been intensively studied. It is well known that C3.spec... 详细信息

ATMOSPHERIC CO2./sub> concentration is predicted to increase to 700μL/L by the middle of the 2.st century. The impacts of raising CO2./sub> on vegetation and ecosystem have been intensively studied. It is well known that C3./sub> species and C4 species responded much differently to double CO2./sub>. Potential enhancement of photosynthesis efficiency induced by double CO2./sub> in C3./sub> plants was almost 66%, but in C4 plants only 4%. The response to double CO2./sub> in C3./sub> species might

关键词： double CO2 seed size seedling growth percentage enhancement.

Synthesis of superheavy nuclei with ^(2.8)U target

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science China(Physics,Mechanics & Astronomy) 2009年第10期52卷 1482-1488页

作者： LIU ZuHua1,3.& BAO JingDong2.4 1 Key Laboratory of Beam Technology and Material Modification of Ministry of Education,beijing normal {2.,beijing 100875,China 2.Department of Physics,beijing normal {2.,beijing 100875,China 3.China institute of Atomic Energy,beijing 102.13.China 4 Center of Theoretical Nuclear Physics,National Laboratory of Heavy Ion Accelerator of Lanzhou,Lanzhou 73.000,China Key Laboratory of Beam Technology and Material Modification of Ministry of Education Beijing Normal University Beijing 100875 China Department of Physics Beijing Normal University Beijing 100875 China China institute of Atomic Energy Beijing 102413 China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou 730000 China

The production of superheavy nuclei with Z=108-116 via hot fusion reactions of the neutron-rich projectiles with 2.8U target is systematically *** results show that the production cross sections of superheavy nuclei do not decrease monotonously as the atomic number Z *** cross sections of the superheavy nuclei at Z = 112.and 115 are enhanced as compared with the whole Z-trend in synthesis of the superheavy nuclei,which clearly illustrates that the reactions with large negative Q-value and shell correction are more favorable to synthesize superheavy nuclei.

关键词： superheavy nuclei fusion reaction cross section 2.8U target