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Effects of binders on the performance of electric double-layer capacitors of carbon nanotube electrodes

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Progress in Natural Science:Materials International 2005年第5期15卷 453-457页

作者： LI Chensha1*, WANG Dazhi1, ZHANG Baoyou2. WANG Xiaofeng1, CAO Maosheng3. and LIANG Ji1(1. Department of Mechanical Engineering, Tsinghua University, Beijing 100084, china 2. {2. for Analysis and Measurement, Harbin Institute of Technology, Harbin 150001, china 3. School of Material Science and Engineering, Tsinghua University, Beijing 100084, china) Department of Mechanical Engineering Tsinghua University Beijing 100084 China center for Analysis and Measurement Harbin Institute of Technology Harbin 150001 China School of Material Science and Engineering Tsinghua University Beijing 100084 China

Polarizable electrodes of electric double layer capacitor (EDLCs) were made from carbon nanotubes. Effects of different binders, which are phenolic resin (PF) and polytetrafluoroethylene (PTFE), on the properties of polarizable electrodes are studied. Results indicate that the microstructure, pore size distribution and specific capacitance of the electrodes with PTFE binder are superior to those electrodes with PF binder after carbonization. The suitable binder (PTFE) for carbon nanotubes electrodes is proposed.

关键词： carbon nanotubes electric double-layer capacitors phenolic resin polytetrafluoroethylene.

Electron microscopy study of the sakhaite from endogenous borate deposit in Hunan, china

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Science china Earth Sciences 2004年第3期47卷 232-238页

作者： LIU Xiangwen1,2. YANG Guangming2. ZOU Huamin3. QU Jing1 & ZHAO Wenxia4 1. Graduate School, china University of Geosciences, Wuhan 43.074, china 2. Test center, china University of Geosciences, Wuhan 43.074, china 3. Physics and Technology College, Wuhan University, Wuhan 43.072. china 4. Test center, Zhongshan University, Guangzhou 5102.5, china Graduate School China University of Geosciences Wuhan 430074 China Test center China University of Geosciences Wuhan 430074 China Physics and Technology College Wuhan University Wuhan 430072 China Test center Zhongshan University Guangzhou 510275 China

Sakhaite specimens from an endogenous borate deposit in Hunan Province, china have been studied in detail by means of transmission electron microscopy (TEM). The selected area electron diffraction (SAED) patterns obtained with different crystal zone axes show that the crystal system is cubic, with a = 1.463.nm. The convergent beam electron diffraction (CBED) patterns indicate that the point group and space group of sakhaite is m3. and Fd3., respec-tively. The space group of synthetic sakhaite determined by Chichagov (1974) is F413.. The possible reasons why the space groups of the natural and the synthetic sakhaites are different are discussed.

关键词： sakhaite, space group, convergent beam electron diffraction (CBED).

The quantification of remote sensing

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Science china(Technological Sciences) 2005年第S2期48卷 1-11页

作者： GU Xingfa1,2.3.TIAN Guoliang1,2. LI Xiaowen1,2.& GUO Jianning4 1. State Key Laboratory of Remote Sensing Science, Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University, Beijing 100101, china 2. The {2. for National Spaceborne Demonstration, Beijing 100101, china 3. Institut National de la Recherche Agronomique, Climat Sol Environnement, 84914 Avignon, France 4. china {2. for Resource Satellite Data and Application, Beijing 10083., china State Key Laboratory of Remote Sensing Science Jointly Sponsored by the Institute of Remote Sensing Applications of Chinese Academy of Sciences and Beijing Normal University Beijing 100101 China

The paper firstly defined the remote sensing information quantification, analyzed the necessity of developing remote sensing quantification, figured out the application guidelines requirement, and pointed out the importance of quantification research. Then taking the remote sensing application research of CBERS-02.data quantification as the example, the paper described the whole quantification system of “remotely sensed digital signal-radiation information-field parameter inversion”. Finally the paper gave the prospect for the development trend of the quantitative remote sensing.

关键词： remote sensing information quantification CBERS-02 radiometric calibration surface parame- ter reversion.

Combined adjustment project of national astronomical geodetic networks and 2.00' national GPS control network

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Progress in Natural Science:Materials International 2005年第5期15卷 435-441页

作者： YANG Yuanxi1*, ZHA Ming2. SONG Lijie3. WEI Ziqing1, WANG Zhouping2. OUYANG Guichong2. XU Bilin2. WU Xiaoping3.and WANG Junqin4(1. Xi'an Research Institute of Surveying and Mapping, Xi'an 710054, {2. 2. Xi'an Informational and Technical center of Surveying and Mapping, Xi'an 710054, {2. 3. Zhengzhou Institute of Surveying and Mapping, Zhengzhou 450052. {2. 4. The First Surveying Team of Tianjin, Tianjin 3.0140, {2.) Xian Research Institute of Surveying and Mapping Xi''an 710054 China Xi''an Informational and Technical center of Surveying and Mapping Xi''an 710054 China Zhengzhou Institute of Surveying and Mapping Zhengzhou 450052 China

The combined adjustment project of the nationwide astronomical geodetic networks and 2.00' national GPS control network involve 48519 terrestrial observational stations and 2.66 GPS observational stations. In the terrestrial network, 2.107 stations are height fixed and 2.0}12.stations are in three dimensions. 440793.terrestrial observations and 183.68 unknowns are involved in the adjustment. The three-dimensional observational models for the adjustment have been established. The crustal deformation influences and corrections are researched. Fast methods of solving partitioned adjustment for super large-scale geodetic network have been studied. The standard deviations of three-dimensional coordinates for all stations are evaluated. As a result of the combined adjustment, a unified national geodetic network with nearly 50000 stations is established, the high accurate three-dimensional geocentric coordinates are obtained. The standard deviation for geoid is averagely 0.2.m, for vertical deflection is about 1.5″, for the horizontal position is about 0.12.m, for the geodetic height is about 0.14 m, and for the three-dimensional position is averagely 0.3.m.

关键词： astronomical geodetic network GPS network combined adjustment datum geocentric coordinates.

Possible mechanism of the effect of convection over Asian-Australian “land bridge” on the East Asian summer monsoon onset

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Science china Earth Sciences 2006年第11期49卷 1223-1232页

作者： HE Jinhai1, WEN Min2. DING Yihui3.& ZHANG Renhe2.1. Jiangsu Key Laboratory of Meteorological Disaster (KLME), Nanjing Institute of Meteorology, Nanjing University of Informa- tion Science and Technology, Nanjing 2.0044, china 2. State Key Laboratory of Severe Weather (LaSW), Chinese Academy of Meteorological Sciences, Beijing 100081, china 3. National Climate center, Chinese Meteorological Administration, Beijing 100081, china Jiangsu Key Laboratory of Meteorological Disaster (KLME) Nanjing Institute of Meteorology Nanjing University of Information Science and Technology Nanjing China State Key Laboratory of Severe Weather (LaSW) Chinese Academy of Meteorological Sciences Beijing China National Climate center Chinese Meteorological Administration Beijing China

The Asian-Australian “land bridge” is an area with the most vigorous convection in Asian monsoon region in boreal spring, where the onset and march of convection are well associated with the onset of East Asian summer monsoon. The convection occurs over Indo-china Peninsula as early as mid-April, which exerts critical impact on the evolution of monsoon circulation. Before mid-April there are primarily sensible heatings to the atmosphere over Indo-china Peninsula and Indian Peninsula, so the apparent heating ratios over them decrease with height. However, after mid-April it changes into latent heating over Indo-china Peninsula due to the onset of convection, and the apparent heating ratio increases with height in mid- and lower troposphere. The vertical distribution of heating ratio and its differences between Indo-china Peninsula and Indian Peninsula are the key factors leading to the splitting of boreal subtropical high belt over the Bay of Bengal. Such mechanism is strongly supported by the fact that the evolution of the vertical heating ratio gradient above Indo-china Peninsula leads that of 850 hPa vorticity over the Bay of Bengal. Convections over Indo-china Peninsula and its surrounding areas further increase after the splitting. Since then, there is a positive feedback lying among the convective heating, the eastward retreat of the subtropical high and the march of monsoon, which is a possible mechanism of the advance of summer monsoon and convection from Indo-china Peninsula to South china Sea.

关键词： Asian-Australian 'land bridge', tropical convection, Indo-china Peninsula, the splitting of boreal subtropical high belt, East Asian summer monsoon onset.

Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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Science china Chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2.3.LI Aimin1,3.CAI Jianguo1,3.MENG Guanhua1,3.& ZHANG Quanxing1,3.1. State Key Laboratory of Pollution Control and Resource Reuse,School of the Environment,Nanjing University,Nanjing 2.0093.china 2. Nanjing College of Chemical Technology,Nanjing 2.0048,china 3. Jiangsu Engineering & Technology Research center for Organic Toxicant Control and Resource Reuse,Nanjing 2.003.,china State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing China Nanjing College of Chemical Technology Nanjing China Jiangsu Engineering & Technology Research center for Organic Toxicant Control and Resource Reuse Nanjing China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2.G, 50# and 3.# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.

A formal model of fair exchange protocols

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Science in china(Series F) 2005年第4期48卷 499-512页

作者： QING Sihan1,2.3.& LI Gaicheng1,2.3.1. Engineering Research {2. for Information Security Technology, Institute of Software, Chinese Aca- demy of Sciences, Beijing 100080, china 2. Beijing Zhongke Ansheng Corporation of Information Technology, Beijing 100080, china 3. Graduate School of the Chinese Academy of Sciences, Beijing 10003., china Engineering Research center for Information Security Technology Institute of Software Chinese Aca- demy of Sciences Beijing Zhongke Ansheng Corporation of Information Technology Graduate School of the Chinese Academy of Sciences

Based on the study of existing fair exchange protocols, this paper sets up an accurate formal model by stepwise refinement. In the process of refinement an unreliable channel is employed to simulate an attack behavior. The model provides a novel formal definition of exchanged items, and presents the formal goals for fairness, accountability, etc., reflecting the inherent requirements for fair exchange protocols across-the-board. In order to check, prove, and design fair exchange protocols effectively and efficiently, the model puts forward a novel property of abuse-freeness which applies to all fair exchange protocols, gives a formal definition for trust strand of the third party, and presents general criteria of designing a secure and effective fair exchange protocol. Taking a typical fair exchange protocol as an example, this paper presents the analysis steps of fair exchange protocols appealing to our model. An unknown attack is uncovered. The analysis reveals the process of a complete attack, discovering deeper reasons for causing an attack. Finally, we modify the flawed protocol and the revised protocol ensures the desirable properties.

关键词： events local causal relation local temporal relation global relation exchanged item security goals.

The mechanism of breakdown in laminar-turbulent transition of a supersonic boundary layer on a flat plate-temporal mode

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Science china(Physics,Mechanics & Astronomy) 2005年第5期48卷 614-625页

作者： HUANG Zhangfeng 1, CAO Wei 1,2.& ZHOU Heng 1,2.1. Department of Mechanics, Tianjin University, Tianjin 3.0072. china 2. Liu-Hui {2. of Applied Mathematics, Nankai University and Tianjin University, Tianjin 3.0072. china Department of Mechanics Tianjin University Tianjin China Liu-Hui center of Applied Mathematics Nankai University and Tianjin University Tianjin China

Temporal mode direction numerical simulation has been done for the transition of a supersonic boundary layer on a flat plate with Mach number 4.5. Analysis of the result showed that during the breakdown process in laminar-turbulent transition, the mechanism causing the mean flow profile to evolve swiftly from laminar to turbulent was that the modification of mean flow profile by the disturbances,when they became larger,led to a remarkable change of its stability characteristics. Though the most unstable T-S wave was of second mode for laminar flow, the first mode waves played the key role in the breakdown process in laminar-turbulent transition.

关键词： supersonic boundary layer, transition, breakdown.

A preliminary study on seismic design criteria of offshore platforms in Bohai Sea of china

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Earthquake Engineering and Engineering Vibration 2010年第2期9卷 223-231页

作者： Peng Yanju1,Lu Yuejun1,Yan Jiaquan2.Tang Rongyu1,Wang Junqin3.and Li Jiagang3.1. Institute of Crustal Dynamics,{2. Earthquake Administration,Beijing 100085,{2. 2. Institute of Geophysics,{2. Earthquake Administration,Beijing 100081,{2. 3. Beijing Research center of {2. National Offshore Oil Corp.,Beijing 10002.,{2. Institute of Crustal Dynamics China Earthquake Administration Beijing 100085 China

This paper analyzes the seismicity in Bohai Sea,introducing a shape factor K to characterize the seismic risk distribution in sub-regions of the sea. Based on the seismic design ground motions for 46 platforms located in the Bohai Sea,a statistical analysis was performed for different peak ground acceleration (PGA) ratios at two different probability levels. In accordance with the two-stage design method,a scheme of two seismic design levels is proposed,and two seismic design objectives are established respectively for the strength level earthquake and the ductility level earthquake. By analogy with and comparison to the Chinese seismic design code for buildings,it is proposed that the probability level for the strength level earthquake and ductility level earthquake have a return period of 2.0 and 1000 - 2.00 years,respectively. The validity of these proposed values is discussed. Finally,the PGAs corresponding to these two probability levels are calculated for different sub-regions of the Bohai Sea.

关键词： fixed offshore platform seismic design level seismic design objective return period Bohai Sea