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s-ordering operator expansions of quantum-mechanical fundamental representations and their applications

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science China(Physics,Mechanics & Astronomy) 2011年第12期54卷 2150-2154页

作者： FAN HongYi 1,3., XU YeJun 2.& YUAN HongChun 3.4.1 Department of Materials science and Engineering, University of science and {2. of China, Hefei 2.002., China 2.Department of Physics Electronic and Engineering, Chizhou University, Chizhou 2.7000, China 3.Department of Physics, Shanghai Jiao Tong University, Shanghai 2.003., China 4.College of Optoelectronic Engineering, Changzhou {3. of {2., Changzhou 2.3.02. China 1. Department of Materials science and Engineering University of Science and Technology of China Hefei 230026 China3. Department of Physics Shanghai Jiao Tong University Shanghai 200030 China2. Department of Physics Electronic and Engineering Chizhou University Chizhou 247000 China4. College of Optoelectronic Engineering Changzhou Institute of Technology Changzhou 213002 China

We show that the quantum-mechanical fundamental representations, say, the coordinate representation, the coherent state representation, the Fan-Klauder entangled state representation can be recast into s-ordering operator expansion, which is elegant in form and has many applications in deriving new operator identities. This demonstrates that Dirac's symbolic method can be merged into Newton-Leibniz integration theory in a broad way.

关键词： s-ordering operator expansion operator identities quantum mechanical representation

Spatial heterogeneity of the driving forces of cropland change in China

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science China Earth sciences 2005年第12期48卷 2231-2240页

作者： LIU Xuhua1,2. WANG Jinfeng1, LIU Mingliang4.1 & MENG Bin1,2.3.1. {3. of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, Beijing 100101, China 2. Graduate {3. of the Chinese Academy of sciences, Beijing 10003., China 3. College of Arts and sciences of Beijing Union University, Beijing 100083. China 4. {3. of Forestry and Wildlife sciences, Auburn University, Auburn, Alabama, AL3.84., USA 1. institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences 100101 Beijing China 2. Graduate school of the Chinese Academy of sciences 100039 Beijing China 3. school of Forestry and Wildlife {2.s Auburn University Auburn AL36849 Alabama USA 4. College of Arts and sciences of Beijing Union University 100083 Beijing China

By using digital satellite remote sensing data acquired in 1987―1989 and 1999―2.00 and GIS combined with the natural and socio-economic data, this paper drew an integrated zonation of the cropland change and its driving forces in China. The results indicated that the cropland change in the study period was constrained by geographical factors and driven by cli-mate change as well as socio-economic system. Moreover, the regional differences of the drivers for cropland change were significant. In the midwest of China, natural condition changes and geographical background were the main constraints and drivers, while in Eastern China, social and economic changes and economic policies were the main driving forces. The cropland loss was nationwide. The dominant factors to cause this decrease included buildup of developing area to attract foreign capital and technologies, changes of industry structure due to urban in-fluence, the change of employment notions thanks to living standard improvement, rapid ur-banization due to the expansion of cities and towns, the diminished farming net income partly because of the global warming effects, and the rapid economic growth stimulated by the con-venient transportation system. These factors interact and interdepend with each other to cause the cropland loss in China recently. The reasons for the increase of cropland were primarily the cultivation and deforestation by the farmers who want to increase income. This study on the mechnism of LUCC relied on the cropland change integrated classification considering the natural or human factors both inside and outside the region, which provides a new approach to study the integrated regionalization and LUCC mechanism.

关键词： land use change, driving force, integrated classification, spatial statistics, cropland, China.

Jet formation and penetration mechanism of W typed shaped charge

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Acta Mechanica Sinica 2009年第1期25卷 107-120页

作者： Cheng Wang Fenglei Huang Jianguo Ning State Key Laboratory of Explosion science and technology,Beijing {2. of technology, {4. Beijing, China State Key Laboratory of Explosion science and technology Beijing Institute of Technology 100081 Beijing China

Existing classical shaped charges are well known for their longer jets capable of achieving large hole depth to hole diameter ratios in metallic targets. However, in some situations, there arises demand to obtain 1：1 ratio for hole depth to hole diameter which is beyond normal shaped charges capability. A new variant of shape charge, named W typed shape charge （WSC）, is proposed in this paper, which can meet the demand of 1：1 ratio, and is based on the geometry that can produce annular jets upon proper initiation scheme. In this paper, we present formation and penetration results of WSC based on three different schemes. We also show that not all WSC designs can form annular jets, only annularly initiated WSC, which also fulfils the ＂Internal-External Liners Equal-Impulse＂ criterion, has the capability to form annular jet. The experimental and numerical results show that when the ratio between annular initiation ring diameter and the charge diameter is 0.75, an annular jet is formed, which was also supported by high speed photographs performed in vacuum. 2. numerical simulations are performed with indigenously developed simulation software, where Eulerian approach with multi-material interface tracking algorithm is utilized, to find various mechanisms involved during jet formation process. The calculation results are found in good agreement with the experimental results, indicating that the interface treatment algorithm proposed in this paper can not only deal with large deformation problem, but also depict clearly the variation of materials interface. It is especially suitable for simulation of the process from liner collapse to formation of shaped charge jet.

关键词： WSC Annular jet Interface tracking Numerical simulation

Feedback image encryption algorithm with compound chaotic stream cipher based on perturbation

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science China(Information sciences) 2010年第1期53卷 191-202页

作者： TONG XiaoJun1 & CUI MingGen2.1school of Computer science and {2., Harbin {4. of {2., Weihai 2.4.0}9, China 2.0} of science, Harbin {4. of {2., Weihai 2.4.0}9, China 1. school of Computer science and {2. Harbin Institute of Technology Weihai 264209 China2. School of Science Harbin Institute of Technology Weihai 264209 China

In this paper, two new one-dimensional chaotic functions are designed using Devaney chaotic definition. And a dynamically shifting compound chaotic function is constructed based on the two new one-dimensional chaotic functions. The properties of compound chaotic functions are also proved. A new feedback image encryption algorithm is designed using the new compound chaos and an image pixel permutation, 3. baker scheme is described in detail. In the scheme, a new dynamic block dividing the 3. baker is put forward using the compound chaotic map, and the key space expands. In order to produce avalanche effect and sensitivity of cipher to plaintext, the round times are designed to control the cycle. The entropy analysis, difference analysis, weak-key analysis, statistical analysis, cipher random analysis, and cipher sensibility analysis depending on key and plaintext are introduced to test the security of the new scheme of image encryption. The tests show that the image encryption method passes the random tests of NIST FIPS 14.-2.2.01) and SP 800-2. standards. This paper also solves the problem of short periods and low precision of one-dimensional chaotic function by perturbation.

关键词： compound chaos stream cipher feedback image encryption 3. baker perturbation

Friction Properties of OTS SAMs and Silicon Surface under Water Lubrication

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Journal of Wuhan University of technology(Materials science) 2009年第2期24卷 273-277页

作者：王馨 State Key Laboratory of Tribology Tsinghua University institute of Nuclear and New Energy technology Tsinghua University

The friction and wear properties of silicon surface covered with octadecyltrichlorosilane （OTS） self-assembled monolayers （SAMs） were investigated by a UMT-2.microtribometer with and without water as lubricant, and then compared with that of bare silicon surface. Dry friction measurement results show that OTS SAMs have a very low friction coefficient compared to bare silicon surface under lower sliding velocity and normal contact load. However, heavy wear occurs on OTS SAMs under higher contact stress and sliding velocity. Under water lubrication, OTS SAMs can prevent wear obviously and meanwhile present low coefficient of friction even under high velocities, The improved frictional and anti-wear property on OTS SAMs surface is attributed to the hydrophobic property of OTS and hydrodynamic effect of water. Furthermore, a wear critical phase diagram for OTS SAMs with and without water was proposed, which indicates that OTS SAMs working under water lubrication owns a wider range of available load and velocity to reduce friction and prevent wear.

关键词： silicon surface OTS SAMs water lubrication friction wear

Oxidation-induced strengthening behavior of reaction formed Al_4.iC_4.ceramics

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Rare Metals 2007年第S1期26卷 94-98页

作者： HUANG Xiaoxiao1,2.,WEN Guangwu1,3.,LIU Ruitang2.,and ZHENG Xin1)1) school of Materials {3. and {2.,Harbin {3. of {2.,Harbin 150001,China 2. school of Material {3. and Chemical Engineering,Harbin Engineering University,Harbin 150001,China 3. school of Materials {3. and {2.,Harbin {3. of {2. at Weihai,Weihai 2.4.0}9,China Harbin Inst Technol Sch Mat Sci & Technol Harbin 150001 Peoples R China Harbin Inst Technol Sch Mat Sci & Chem Engn Harbin 150001 Peoples R China Harbin Inst Technol Sch Mat Sci & Technol Weihai 264209 Peoples R China

The bending strengths of Al4.iC4.ceramics were investigated from room temperature to 13.0 ℃ in air and in vacuum,*** is a novel property that the bending strength increases with increasing test temperatures up to 13.0 ℃ in *** strength value of Al4.iC4.ceramics is 4.9.7 MPa at 13.0 ℃ in air,which is about 1.5 times of that at room temperature(3.0 MPa).The self-healing behavior of the flaws on the specimen surface due to the oxidation of the surface layer of the Al4.iC4.ceramics is considered as the main enhancement mechanism at high temperatures.

关键词： calcination and hot pressing surface strength Al_4.iC_4

Final Temperature Prediction Model of Molten Steel in RH-TOP Refining Process for IF Steel Production

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Journal of Iron and Steel Research International 2012年第3期19卷 1-5页

作者： WANG Yu-nan1, BAO Yan-ping1, CUI Heng2. CHEN Bin3. JI Chen-xi3.(1. State Key Laboratory of Advanced Metallurgy, University of science and technology Beijing, Beijing 100083. China 2. Engineering Research {2., University of science and technology Beijing, Beijing 100083. China 3. Shougang Research {2. of technology, Beijing 10004., China) [a] State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Beijing 100083 China [b] Engineering Research institute University of Science and Technology Beijing Beijing 100083 China [c] Shougang Research institute of technology Beijing 100041 China

In order to precisely control the final temperature of molten steel in RH （Ruhrstahl Heraeus）-TOP blowing refining, the final temperature prediction models of molten steel in RH-TOP blowing refining process for Interstitial Free （IF） steel production were established under the condition of oxygen blowing and non-oxygen blowing respec- tively. The results show that the beginning molten steel temperature of refining and the amount of added scrap were influential factors, the baking temperature in vacuum chamber was a factor that had small influence. When the model was operated, the hitting probability was above 95%（under the condition of both oxygen blowing and non-oxygen blo- wing） of prediction deviation ±10℃. The accuracy is analyzed.

关键词： RH-TOP molten steel temperature prediction model

A restudy of Oryctocephalus indicus (Reed,1910)

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Progress in Natural science:Materials International 2006年第11期16卷 1177-1182页

作者： ZHAO Yuanlong~1**, YUAN Jinliang~2. PENG Shanchi~ 2.3., YANG Xinglian~1, PENG Jin~1, LIN Jihpai~4. and GUO Qingjun~5(1. College of Resource and Environment of Guizhou University, Guiyang 550003. China 2. Nanjing institute of Geology and Palaeontology, Chinese Academy of {4.s, Nanjing 2.0008, China 3. State Key Laboratory of Papaeobiology and Stratigraphy, Nanjing institute of Geology and Palaeontology, Nanjing 2.0008, China 4. Department of Geological {4., Ohio State University, Columbus, OH 4.2.0, USA 5. institute of Geochemistry, Chinese Academy of {4.s, Guiyang 550002. China) College of Resource and Environment of Guizhou University Guiyang 550003 China Nanjing institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China State Key Laboratory of Papaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Nanjing 210008 China Department of Geological science Ohio State University Columbus OH 43210 United States institute of Geochemistry Chinese Academy of Sciences Guiyang 550002 China

Restudy on morphology of Oryctocephalus indicus (Reed, 1910), based on specimens from Guizhou, China and Nevada USA, suggests that the subspecies regarded previously as Oryctocephalus indicus indicus (Reed, 1910), O. indicus latus Zhao et Yuan 2.02. and O. indicus kobayashi Saito, 193.2} are synonymous, and Oryctocephalus americanus Sundberg et McCollum, 2.03.is a similar form of O. indicus. Oryctocephalus indicus is rediagnosed as having a glabella that is subconical in outline and tapering forward slightly; a thorax that comprises 12.segments, and a small pygidium that bears 2.3.axial rings with a terminal piece and a postaxial ridge. Oryctocephalus indicus is widely distributed in eastern Guizhou and ranges through a great interval of Kaili Formation. Its first appearance is almost identical with these events of trilobite extinction-recovery occurring at the end of the Early Cambrian, the alternation of acritach assemblages, the change of trace elements (REE) and stable isotopes (carbon) at the Wuliu-Zengjiaya section. As one of the key forms for defining the traditional Lower-Middle Cambrian boundary (the base of Cambrian Series 3.and Stage 5 in the new Cambrian chronstratigraphic standard), O. indicus has received detailed study and has more advantages than other species such as Ovatoryctocara granulata Tchernysheva, 1962.or Arthricocephalus chauveaui Bergeron, 1899.

关键词： Oryctocephalus indicus restudy Kaili Formation Cambrian Guizhou China.

Gas formation mechanism of marine carbonate source rocks in China

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science China Earth sciences 2005年第4期48卷 441-453页

作者： ZHAO Wenzhi1, WANG Zhaoyun1, HE Haiqing2. ZHANG Mingjie3. WANG Hongjun1, WANG Yunpeng4.& QIN Yong5 1. Research institute of Petroleum Exploration & Development, PetroChina, Beijing 100083. China 2. PetroChina Exploration & Production, Beijing 100011, China 3. Department of Geology, Lanzhou University, Lanzhou 73.000, China 4. Guangzhou Geochemical institute, Chinese Academy of {2.s, Guangzhou 51064., China 5. China University of Mining and {3., Xuzhou 2.1000, China 1. Research institute of Petroleum Exploration & Development 100083 PetroChinaBeijin China 2. PetroChina Exploration & Production 100011 Beijing China 3. Department of Geology Lanzhou University 730000 Lanzhou China 4. Guangzhou Geochemical institute Chinese Academy of Sciences 510640 Guangzhou China 5. China University of Mining and technology 221000 Xuzhou China

By breaking through the conventional ideology on the study of gas-formation mechanism of source rocks which focused on merely the characteristics of source rocks them- selves, and based on the development and distribution characteristics of marine carbonate source rocks in the medium-to-bottom parts of the Chinese superimposed sedimentary basins as well as various processes in the course of gas generation and reservoir forming, the complex hydrocarbon-generating model of carbonates is established. Such a model concerns not only the “three-stage” gas formation characteristics of carbonates, but also the gas generation process due to a thermal cracking of oil and the re-generation process of gas from heated secondary organic matters during the gas-generation and reservoir-forming course. The high-quality hy- drocarbon generating matter of marine carbonate source rocks determined a high gas-oil ratio and tended to form paleo-oil-reservoirs, representing an enrichment process of organic matters. The thermal cracking of oil in palaeo-oil-reservoirs is an important means for the effective forma- tion of gas reservoirs. The secondary organic matters in carbonate reservoirs may regenerate gas after a secondary deep burial, thus becoming an effective gas source.

关键词： carbonate, three-stage hydrocarbon generation, inhibitive effect of maturity, oil-cracking gas, second-ary asphalt gas.