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控制离子云混沌运动中的不稳定性

物理学报 1997年第11期46卷 2117-2123页

作者：海文华段宜武朱熙文施磊罗学立何春山湖南师范大学物理系中国科学院武汉物理与数学研究所

射频阱中离子云与检测场的相互作用由Ｄｕｆｉｎｇ方程描述．在小阻尼条件下，得到嵌于混沌吸引子中的不稳定周期解及其稳定性条件．分析表明，调节直流扫描电压等参数去拟合该条件，可以控制混沌运动中的不稳定性．有关实验定性支持这... 详细信息

射频阱中离子云与检测场的相互作用由Ｄｕｆｉｎｇ方程描述．在小阻尼条件下，得到嵌于混沌吸引子中的不稳定周期解及其稳定性条件．分析表明，调节直流扫描电压等参数去拟合该条件，可以控制混沌运动中的不稳定性．有关实验定性支持这一结论．

关键词：射频阱离子云混沌运动不稳定性

MEASUREMENT OF PLASMA POTENTIAL USING EMISSIVE PROBE IN A MAGNETIC MI

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国防科技大学学报 1995年第3期17卷 104-108页

作者： Zhang Jiande(Department of Applied physics, NUDT, {2., 410073)Fang Yude Qiu Lijian Ren Zhaoxing(institute of Plasma physics, Academia Sinica, Hefei, 2.0031)

ＭＥＡＳＵＲＥＭＥＮＴＯＦＰＬＡＳＭＡＰＯＴＥＮＴＩＡＬＵＳＩＮＧＥＭＩＳＳＩＶＥＰＲＯＢＥＩＮＡＭＡＧＮＥＴＩＣＭＩＲＲＯＲＺｈａｎｇＪｉａｎｄｅ（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＰｈｙｓｉｃｓ，ＮＵＤＴ，Ｃ... 详细信息

ＭＥＡＳＵＲＥＭＥＮＴＯＦＰＬＡＳＭＡＰＯＴＥＮＴＩＡＬＵＳＩＮＧＥＭＩＳＳＩＶＥＰＲＯＢＥＩＮＡＭＡＧＮＥＴＩＣＭＩＲＲＯＲＺｈａｎｇＪｉａｎｄｅ（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＰｈｙｓｉｃｓ，ＮＵＤＴ，Ｃｈａｎｇｓｈａ，４１００７３）Ｆａ...

关键词：离子体电势测量发射探针磁镜

Effect of Spontaneous Emission on Both Atomic Dynamics and Momentum Transfer of an Atomcavity System

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Chinese Journal of Lasers 1999年第4期8卷 3-5页

作者： YI Xuexi 1 WANG Haijun 2. BA Xinwu 2. WANG Jianwei 3 ( 1 institute of Theoretical physics, Northeast {2. university, Changchun 13002., China 2.Department of Chemistry, Hebei university, Baoding 071000, China 3 Department of 东北师范大学理论物理所吉林长春 130024 河北大学化学系河北保定 071000 河北大学化学系河北保定喀什师范学院物理系新疆喀什 844000

The dynamics of an atom coupling to a quantized cavity field have been studied. The atom is treated as a two level system with a spontaneous emission rate. The transition probabilities have been given for both adiabatic and non adiabatic situations. For a special Λ type atom with dark state, the problem of momentum transfer is discussed in details. The influence of spontaneous emission on validity of the adiabatic approximation is also discussed.

关键词： atomic dynamic momentum transfor quantized cavity

Fabrication, microstructure and properties of SiCp/Cu heat sink materials

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Rare Metals 2006年第z2期25卷 232-236页

作者： KANG Suk-bong Korea institute of Machinery and Materials 66 Sangnam-dong Changwon 641-010 Korea

Cu-coated powder was fabricated by electroless plating process, and the composition and morphology of coated powder were studied. Moreover, Cu-30, 40, 50 vol.%SiCp heat sink materials were fabricated by hot pressing using coated and uncoated powder. And the microstructure and thermophysical properties of the heat sink materials were also studied. The results show that SiCp particles distribute uniformly in heat sink materials and the interface between SiCp particles and Cu matrix is clear and well bonded. On the condition of same volume fraction of SiCp, the thermal conductivity of the material using coated powder is larger than that of the material using uncoated powder. Under experiment conditions, the thermal conductivity and coefficient of thermal expansion of Cu-30 vol.%SiCp heat sink material is 2.6.2.W·m-1·K-1 and 9.9×10-6/K (30-2.0 ℃) respectively. It provides important reference data for future experiments.

关键词： heat sink material electroless copper plating coefficient of thermal expansion thermal conductivity

Characterization of microarc oxidation coatings on pure titanium

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Rare Metals 2003年第1期22卷 42-48页

作者： XUE Wenbin, WANG Chao, Li Yongliang, and CHEN RuyiKey Laboratory for Beam Technology and Materials Modification, institute of Low Energy Nuclear physics, Beijing {2. university, Beijing 100875, China 北京师范大学射线束技术与材料改性教育部重点实验室北京 100875

Key Laboratory for Beam Technology and Materials Modification, institute ofLow Energy Nuclear physics, Beijing {2. universityThe morphology, composition, and phase structure of the oxide coatings produced on the surface ofpure titanium by alternating-current microarc discharge in aluminate solution were investigated byX-ray diffraction and scanning electron microscopy. The profiles of the hardness H and the elasticmodulus E in the coatings were determined using a nanoindentation method. The concentrationdistributions of Ti, Al, and O in the coating show that this coating over 30 mu m thick contains twolayers: an outer layer and an inner layer. The oxide coating is mainly composed of TiO_2.rutile andAl_2.iO_5 compounds. During oxidation, the temperature in the microarc discharge channel was veryhigh to make the local coating molten. From the surface to the interior of the coating, H and Eincrease gradually, and then reach maximum values of 9.78 GPa and 176 GPa respectively at a distanceof 7 mu m from the coating/titanium interface. They are also rather high near the interface.

关键词： pure titanium ceramic coating microarc oxidation microstructure nanoindentation

fMRI time series analysis based on stationary wavelet and spectrum analysis

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Progress in Natural Science:Materials International 2006年第11期16卷 1171-1176页

作者： ZHI Lianhe~ 1,2.3 , ZHAO Xia~4, SHAN Baoci~1**, PENG Silong~5, YAN Qiang~1, YUAN Xiuli~1 and TANG Xiaowei~ 1,6 (1. Key Laboratory of Nuclear Analysis Techniques, institute of High Energy physics, Chinese Academy of Sciences, Beijing 100049, China 2. Graduate School of Chinese Academy of Sciences, Beijing 100049, China 3. D{2. of physics, Zhoukou normal university, Zhoukou 466100, China 4. Research Imaging Center, university of Texas Health Science Center, San Antonio, Texas 782.9, USA 5. National ASIC Design and Engineering Center, institute of Automation, Chinese Academy of Sciences, Beijing 100049, China 6. D{2. of physics, Zhejiang university, Hangzhou 31002., China) [a]Key Laboratory of Nuclear Analysis Techniques Institute of High Energy Physics Chinese Academy of Sciences Beijing China [b]Graduate School of Chinese Academy of Sciences Beijing China [c]Department of physics Zhoukou Normal University Zhoukou China [d]Research Imaging Center University of Texas Health Science Center San Antonio Texas USA [e]National ASIC Design and Engineering Center Institute of Automation Chinese Academy of Sciences Beijing China [f]Department of physics Zhejiang University Hangzhou China

The low signal to noise ratio (SNR) of functional MRI (fMRI) prefers more sensitive data analysis methods. Based on stationary wavelet transform and spectrum analysis, a new method with high detective sensitivity was developed for analyzing fMRI time series, which does not require any prior assumption of the characteristics of noises. In the proposed method, every component of fMRI time series in the different time-frequency scales of stationary wavelet transform was discerned by the spectrum analysis, then the components from noises were removed using the stationary wavelet transform, finally the components of real brain activation were detected by cross-correlation analysis. The results obtained from both simulated and in vivo visual experiments illustrated that the proposed method has much higher sensitivity than the traditional cross-correlation method.

关键词： fMRI stationary wavelet transform spectrum analysis data analysis.

Latest progress on interactions between VLF/ELF waves and energetic electrons in the inner magnetosphere

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Science China Earth Sciences 2010年第3期53卷 317-326页

作者： XIAO FuLiang1,2. ZONG QiuGang3, SU ZhenPeng4, TIAN Tian3 & ZHENG HuiNan4 1 School of physics and Electronic Sciences, changsha {2. of Science and Technology, changsha 410004, China 2.State Key Laboratory of Space Weather, Chinese Academy of Sciences, Beijing 100190, China 3 institute of Space physics and Applied Technology, Peking {2., Beijing 100871, China 4 CAS Key Lab for Basic Plasma Science, School of Earth and Space Sciences, {2. of Science and Technology of China, Hefei 2.002., China 1. School of physics and Electronic Sciences Changsha University of Science and Technology Changsha 410004 China2. State Key Laboratory of Space Weather Chinese Academy of Sciences Beijing 100190 China3. Institute of Space Physics and Applied Technology Peking University Beijing 100871 China4. CAS Key Lab for Basic Plasma Science School of Earth and Space Sciences University of Science and Technology of China Hefei 230026 China

Interactions between very/extremely low frequency (VLF/ELF) waves and energetic electrons play a fundamental role in dynamics occurring in the inner magnetosphere. Here, we briefly discuss global properties of VLF/ELF waves, along with the variability of the electron radiation belts associated with wave-particle interactions and radial diffusion. We provide cases of electron loss and acceleration as a result of wave-particle interactions primarily due to such waves, and particularly some preliminary results of 3D evolution of phase space density from our currently developing 3D code. We comment on the existing mechanisms responsible for acceleration and loss, and identify several critical issues that need to be addressed. We review latest progress and suggest open questions for future investigation.

关键词： wave-particle interaction VLF/ELF waves energetic electrons acceleration and loss inner magnetosphere

The Glacier Area Changes in the Qangtang Plateau Based on the Multi-temporal Grid Method and its Sensitivity to Climate Change

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Journal of Mountain Science 2011年第6期8卷 882-893页

作者： WANG Liping XIE Zichu WANG Xin LIU Shiyin DING Liangfu SHANGGUAN Donghui The College of Resources and Environmental Science Hunan Normal University Changsha China Cold and Arid Regions Environmental and Engineering Research institute Chinese Academy of Sciences Lanzhou China Department of Geography Hunan University of Science and Technology Xiangtan China

Glacier area changes in the Qangtang Plateau are analyzed during 1970-2.00 using air photos,relevant photogrammetric maps and satellite images based on the multi-temporal grid *** results indicate that the melting of glaciers accelerated,only a few of glaciers in an advancing state during 1970-2.00 in the whole Qangtang ***,the glaciers seemed still more stable in the study area than in most areas of western *** estimate that glacier retreat was likely due to air temperature warming during 1970-2.00 in the Qangtang ***,the functional model of glacier system is applied to study climate sensitivity of glacier area changes,which indicates that glacier lifespan mainly depends on the heating rate,secondly the precipitation,and precipitation increasing can slow down glacier retreat and make glacier lifespan prolonged.

关键词： The Qangtang Plateau Glacier change Multi-temporal Climate change Functional model ofglacier system Simulation

Fuzzy cluster analysis of the provenance of ancient Yaozhou porcelain body

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Chinese Science Bulletin 2003年第1期48卷 27-30页

作者： LI Guoxia1, ZHAO Weijuan1, LI Rongwu2. XIE Jianzhong1, FENG Songlin3, FAN Dongyu3, ZHANG Ying3, CAI Zhifang3, ZHUO Zhenxi4 & GAO Zhengyao1 1. Faculty of Physical Engineering, Zhengzhou university, Zhengzhou 450052. China 2. Department of {2., Beijing normal university, Beijing 100875, China 3. High Energy {2. institute, the Chinese Academy of Sciences, Beijing 100080, China 4. Archaeology Research institute, Shanxi Province, Xian 710000, China Correspondence should be addressed to Li Guoxia (e-mail: Liguoxia@ ***) Faculty of Physical Engineering Zhengzhou University Zhengzhou 450052 China Department of physics Beijing Normal University Beijing 100875 China High Energy physics institute Chinese Academy of Sciences Beijing 100080 China Archaeology Research institute Shanxi Province Xi'an 710000 China

The technique of neutron activation analysis (NAA) has been employed to measure the content of 2. kinds of elements in the sample of Yaozhou porcelain bodies. Then a fuzzy cluster analysis has been conducted to the NAA data and a diagram of the dynamic fuzzy cluster analysis has been achieved. The results indicate that the batch of ancient Yaozhou porcelain bodies, which were of different overglaze color and were produced by different kilns during a period of over 800 years from the Tang Dynasty (618—907 A.D.) to the Yuan Dynasty (12.1—1368 A.D.), has shared a stable and concentrated raw material source. Provenances of por-celain bodies from different times, though having their spe-cific independence, enjoy a close relationship and are not far from one another. Provenances of porcelain bodies made during the Tang Dynasty and the Five Dynasties (907—960 A.D.) are found to be closer to one another, while those of the Song (960—12.9 A.D.) and the Jin Dynasty (1115—12.4 A.D.) are comparatively concentrated in certain areas and are dif-ferent from those of the Tang Dynasty. Both the tri-colored glazed pottery made in Yaozhou kilns during the Tang Dy-nasty and the Yaozhou porcelain bodies of the Tang period are from the same provenance.

关键词：古代姚州瓷胎窑址粘土矿原料来源中子活化分布模糊聚类分析