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Multifractal Decomposition of Statistically Self-Similar Sets

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Acta Mathematica Sinica,English Series 2001年第3期17卷 507-516页

作者： Jing Hu YU wuhan institute of physics and mathematics,The chinese academy of sciences,wuhan 430071,P.R.china E-mail:ding@wipm.whcnc.ac.cnDi He HU College of mathematics and Statistics.wuhan University,wuhan 430072,P.R.china E-mail:dhhu@*** wuhan institute of physics and mathematics The Chinese Academy of Sciences Wuhan 430071 P. R. China College of mathematics and Statistics Wuhan University Wuhan 430072 P. R. China

Let K be a statistically self-similar set defined by *** this paper,we construct a random measure ρ which is supported by K and study the multifractal decomposition for K with p. Under such a decomposition,we obtain ... 详细信息

关键词： Statistically self-similar sets Multifractal decomposition Spectrum function

Surface modification of γ-Al_2O_3 by sodium ions

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chinese Science Bulletin 2001年第3期46卷 188-193页

作者： DENG Feng, YUE Yong, DU Youru, YE Chaohui, KONG Yuhua, WANG Guoxing & LI Xiaoding1. Laboratory of Magnetic Resonance and Atomic and Molecular physics, wuhan institute of physics and mathematics, chinese academy of sciences, wuhan 430071, china 2. Hubei institute of Chemistry, wuhan 430074, china Laboratory of Magnetic Resonance and Atomic and Molecular physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China Hubei institute of Chemistry Wuhan China

1H/23Na double resonance NMR techniques were employed to study the modification of surface hydroxyls on Y-Al2O3 by sodium ions. 1H-23Na cross polarization (CP) experiment can resolve three kinds of sodium cations that are closely associated with surface hydroxyl groups, while the signal of deposited salt-Na2CO3, which is not connected to surface hydroxyl groups, is completely suppressed. 1H{23Na} spin echo double resonance experiments reveal the surface modification in more detail. At low Na+ coverage (5%, 10%), the acidic hydroxyl groups are preferentially coordinated with sodium ions, while both the acidic and the basic hydroxyl groups are accessible for sodium ions at highcoordination that causes proton of the OH groups to be easily dissolved, which is evidenced by the fact that with calcination temperature of the catalysts increasing, the acidic hydroxyl groups are preferentially removed and only the basic hydroxyl groups remain when the calcination temperature is raised to 600℃.

关键词： surface modification γ-Al2O3 NMR hydrodesulfu-rization catalyst.

POINTWISE MULTIPLIERS OF DIRICHLET TYPE SPACES ON THE UNIT BALL OF C^n

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Journal of Systems Science & Complexity 2001年第3期14卷 306-310页

作者： FENG Shaoji (institute of Systems Science, academy of mathematics and Systems Science, chinese academy of sciences, Beijing 100080 wuhan institute of physics and mathematics, chinese academy of sciences, wuhan 430071, china) 中科院系统科学所北京 100080

In this paper, we establish a criterion for a holomorphic function to be a pointwise multiplier of Dirichlet type spaces, and use this criterion to consider the inclusion relations among M(Dr), α-Bloch spaces and Qp ... 详细信息

关键词： Dirichlet type spaces pointwise multipliers inclusion relation.

A REMARK OF THE HLDER ESTIMATE OFSOLUTIONS OF SOME DEGENERATE PARABOLICEQUATIONS

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Acta Mathematica Scientia 1999年第4期19卷 463-468页

作者：钱黎文范文涛 wuhan institute of physics and mathematics The Chinese Academy of Sciences. Wuhan 430071 China

In this paper, the Cauchy problem of the degenerate parabolic equationsis studied for some cases, and the explicit Holder estimates of the solution u with respectto x is given.

关键词： Cauchy problem degenerate parabolic equation H lder estimate

Photodissociation/photoionization processes of chlorobromomethane induced by femtosecond laser pulses with pump-probe scheme

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chinese Science Bulletin 2008年第5期53卷 681-686页

作者： ZHANG Feng1,2, WEI ZhengRong1,2, CAO ZhenZhou1,2, ZHANG ChangHua1,2 & ZHANG Bing1,2 1 State Key Laboratory of Magnetic Resonance and Atomic and Molecular physics, wuhan institute of physics and mathematics, chinese academy of sciences, wuhan 430071, china 2 Graduate University of chinese academy of sciences, Beijing 100039, china State Key Laboratory of Magnetic Resonance and Atomic and Molecular physics Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences Wuhan China Graduate University of chinese academy of sciences Beijing China

The photodissociation/photoionization processes of chlorobromomethane (CH_2BrCl) induced by fem- tosecond laser pulses have been investigated using pump-probe scheme combined with the time-of-flight mass spectra. The dominate photoproducts are observed at different delay time of the pump (400 nm) and probe (800 nm) pulses and the corresponding time-dependence of them is obtained. The results show that the decaying time of the molecule CH_2BrCl in the A-band is in the 100 fs. The decaying tendencies of the fragment ions (CH_2Cl^+ and CH_2Br^+) and the parent ion (CH_2BrCl^+) are almost the same and the relative ratios of the yields of them keep constant during the delay time of 0 to 150 fs. These facts suggest that the fragment ions come from the fragmentation of the parent ions in excited electronic states. The probabilities to form CH_2Cl^+ and CH_2Br^+ are obtained from the relative ratio of the ion intensity and are about 71.6% and 14.2%, respectively.

关键词：毫微秒激光氯溴化甲烷激光探针光解作用光化电离作用

HAUSDORFF DIMENSION OF GENERALIZED STATISTICALLY SELF-AFFINE FRACTALS

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Acta Mathematica Scientia 2004年第3期24卷 421-433页

作者：余旌胡丁立新 wuhan institute of physics and mathematics The Chinese Academy of Sciences Wuhan 430071 China State Key Laboratory of Software Engineering Wuhan University Wuhan 430072 Chinahe authors consider generalized statistically self-affine recursive fractals K with random numbers of subsets on each level. They obtain the Hausdorff dimensions of K without considering whether the subsets on each level are non-overlapping or not. They also give some examples to show that many important sets are the special cases of their models.

The authors consider generalized statistically self-affine recursive fractals K with random numbers of subsets on each level. They obtain the Hausdorff dimensions of K without considering whether the subsets on each level are non-overlapping or not. They also give some examples to show that many important sets are the special cases of their models.

关键词： Self-affine contraction map statistically recursive set statistically self-affine set Hausdorff measure Hausdorff dimension singular value function

Correlation of Behavior Changes and BOLD Signal in Alzheimer-like Rat Model

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Acta Biochimica et Biophysica Sinica 2004年第12期36卷 803-810页

作者： Zheng-Hui HU#, Xiao-Chuan WANG1#, Li-Yun LI3, Mai-Li LIU3, Rong LIU1, Zhiqun LING1, Qing TIAN1, Xiao-Wei TANG, Yi-Gen WU2*, and Jian-Zhi WANG1* Department of physics and Bio-X disciplinary Laboratory, Zhejiang University, Hangzhou 310027,china 1 Department of Pathophysiology, Tongji Medical College, Huazhong University of Science and Technology, wuhan 430030, china 2institute of High Energy physics and Key Laboratory of Nuclear Analysis Techniques, chinese academy of sciences, P.O. Box 918, Beijing 100039, china 3wuhan institute of physics and mathematics, State Key Laboratory of Magnetic Resonance and Atomic and Molecular physics, chinese academy of sciences, wuhan 430071, china Department of physics and Bio-X disciplinary Laboratory Zhejiang UniversityHangzhou 310027China Department of Pathophysiology Tongji Medical College Huazhong University of Science and TechnologyWuhan 430030 China wuhan institute of physics and mathematics State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics Chinese Academy of SciencesWuhan 430071 China institute of High Energy physics and Key Laboratory of Nuclear Analysis Techniques Chinese Academy of SciencesP.O. Box 918 Beijing 100039 China

To explore a potential means for the early diagnosis of Alzheimer disease, we studied the relationship of resting T2* signal and tau hyperphosphorylation/spatial memory deficit. The rat model with tau hyperphosphorylation and spatial memory deficit was established by bilateral hippocampi injection of isoproterenol (IP). Then, the correlative alteration between resting T2* signal and spatial memory retention was assessed with blood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) study and Morris Water Maze test, and Western blot was employed to confirm tau hyperphosphorylation. The analysis showed following results. (1) Tau phosphorylation at Ser396/Ser404 and Ser199/Ser202 was signifi- cantly increased in IP-injected rats as detected by PHF-1 and tau-1, respectively. (2) An AD-like spatial memory retention disturbance was induced at 24 h after isoproterenol injection. (3) A sensitivity threshold of resting T2* signal intensity, which separated the IP-treated rats from vehicle control, was obtained by applying linear regression analysis, and an estimated sensitivity statistical threshold was at 32.62. These results suggest that resting T2* signal may serve as a noninvasive quantitative marker in predicting AD-like spatial memory deficits and tau hyperphosphorylation.

关键词： Alzheimer disease (AD) functional magnetic resonance imaging (fMRI) isoproterenol (IP) Morris Water Maze diagnosis

NORMAL FAMILY OF COMPOSITIONS OF HOLOMORPHIC FUNCTIONS AND THEIR HIGH ORDER DERIVATIVES

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Acta Mathematica Scientia 2003年第4期23卷 544-548页

作者：邓方文 wuhan institute of physics and mathematics CAS Wuhan 430071 China

Let F = {f} be a family of entire functions and f(k) the k-th derivative of f. The author studies the relation of the nomality of F and that of {f(k) o f : f ∈F} or {f o f(k):f∈F}.

关键词： Normality entire function

Meteor radar observation of circulation near mesopause over wuhan

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chinese Science Bulletin 2003年第15期48卷 1634-1638页

作者： XIONG Jiangang, WAN Weixin, NING Baiqi & LIU Libo wuhan institute of physics and mathematics, chinese academy of sciences, wuhan 430071, china Correspondence should be addressed to Xiong Jiangang (e-mail: xjg@***) wuhan institute of physics and mathematics Chinese Academy of Sciences Wuhan 430071 China

The wuhan meteor radar is the first all-sky meteor radar in china. The circulation near the mesopause from February to September 2002 is studied based on the data obtained by the wuhan meteor radar. The zonal wind is usually eastward in winter from 80 to 100 km. The mean zonal wind become westward from March to early of May, when the winter circulation reverses to the summer circulation. But at the meteor heights, the zonal circulation usually becomes eastward after the middle of May. The meridional circulation is always equatorward. The peaks of the meridional wind move downward with the height, and the peak value reaches its maximum of 21 ms-1 in July. Having made a comparison between monthly mean wind and HWM93 model wind, the value of southward wind, the maximal value of eastward wind as well as the reversal height of zonal wind are found to be quite different from each other.

关键词：武汉市气象雷达带状气流数据采集中间层顶