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Synthesis,field emission and microwave absorption of carbon nanotubes filled with ferromagnetic nanowires

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Science china(Technological Sciences) 2010年第6期53卷 1453-1459页

作者： LV RuiTao1,KANG FeiYu1,GU JiaLin1,WANG KunLin2.& WU DeHai2.1 Laboratory of Advanced materials,{3. of materials Science and {3.,Tsinghua University,beijing 100084,china 2.{3. of Mechanical {3.,Tsinghua University,beijing 100084,china Laboratory of Advanced materials Department of Materials Science and Engineering Tsinghua University Beijing China department of Mechanical engineering Tsinghua University Beijing China

Carbon nanotubes filled with ferromagnetic metal nanowires (M-CNTs) were synthesized by using chlorine-contained benzene (***) as *** wall thicknesses of M-CNTs synthesized by trichlorobenzene are much thinner than those by precursor without Cl (***).As-synthesized thin-walled M-CNTs exhibit remarkably enhanced field electron emission performance with a low turn-on field of 0.3.V/μm and better field-emission ***-absorption coatings were made by dispersing as-synthesized M-CNTs into epoxy resin *** is found that the reflection losses in S-band (2.4 GHz),C-band (4-8 GHz) and X-band (8-12.GHz) are enhanced in the order of FeCoNi-CNTs 2.3. kg/m2.when the coating thickness is 2.0 *** demonstrates that M-CNTs are promising to be used as lightweight and wide-band microwave absorbers.

关键词： carbon nanotubes ferromagnetic nanowires field emission microwave absorption

Sorption behavior of U(VI), ^(2.4)U(VI) and ^(2.8)U(VI) onto fracture-filling clays in Beishan granite, Gansu: Application to selecting the site of high-level radwaste repository in china

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Science china Earth Sciences 2005年第10期48卷 1649-1655页

作者： MIN Maozhong1,2. LUO Xingzhang3. WANG Ju4, JIN Yuanxin4 & WANG Rucheng1 1. department of Earth Sciences, State Key Laboratory of Mineral Deposit Research, Nanjing University, Nanjing 2.0093.{3. 2. Center of {2. Analysis, Nanjing University, Nanjing 2.0093.{3. 3. department of Environmental Science and engineering, Nanjing University, Nanjing 2.0093.{3. 4. beijing Geology Institute, Nuclear Industry, beijing 10002.,{3. Nanjing University Nuclear Industry

The first results of sorption experiments of U(VI), 2.4U(VI) and 2.8U(VI) onto original (unpurified) fracture-filling clays from No.1 monzonitic granite intrusion, Beishan area, Gansu Province, china are reported. The monzonitic granite intrusion is a potential location for a high-level radwaste (HLW) repository in china. The present experimental results show that the maximum U(VI) sorption reached 92. at near-neutral pH and the distribution coefficient (Kd) was 12.6 mL/g. A high sorption capacity of the fracture-filling clays in host rock on radioactive ele-ments is necessary for HLW deep geological disposal repository. No preferential sorption of 2.4U onto the clays was found. Finally, the sorption of U(VI) onto the clays was also modeled using a surface complexation model.

关键词： HLW geological disposal repository, granite, uranium, radionuclide, clay, sorption.

Spatiotemporal model of open-pit based on 3.D deposit model

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中国有色金属学会会刊：英文版 2011年第S3期21卷 616-620页

作者： XIA Chun-lin1, ZHOU Hui1, LI Qing-yuan2. MA Zhen-li3.1. School of Geomatics, Liaoning Technical University, Fuxin 12.000, china 2. State Key Laboratory for GIS engineering, Chinese Academy of Surveying and Mapping, {2. 10083., china 3. Yinchuan College, china University of Mining and Technology, Yinchuan 750011, china School of Geomatics Liaoning Technical University Fuxin 123000 China State Key Laboratory for GIS engineering Chinese Academy of Surveying and Mapping Beijing 100830 China Yinchuan College China University of Mining and Technology Yinchuan 750011 China

A new method was put forward to make up the three-dimensional deposit model, and the spatiotemporal models of open-pit with temporal dynamics were also studied combined with the corrected models of multilevel ground states so as to bring the three-dimensional open-pit model at different time and its model serial formed from the evolvement into the management of temporal dimension in order to realize the spatial three-dimension and temporal dynamic for the mining management in open-pits,which makes this model easy to query and analyze 3.D information, also help surface mining replaying and stope evolution forecasting. Finally, the time-spatial model was established to show the dynamic mining on some open-pit under the windows XP and VC++ environment.

关键词： 3. model of deposit three-dimensional model mixed model temporal model open-pit

Enhancing the capacitances of electric double layer capacitors based on carbon nanotube electrodes by carbon dioxide activation and acid oxidization

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Science china(Technological Sciences) 2010年第5期53卷 1234-1239页

作者： LI ChenSha1,2.QIAO YingJie1,WU JianJun2.WANG DaZhi2.& YUAN DianBo2.1 department of materials Science,Harbin {2. University,Harbin 150001,{3. 2.department of Mechanical {2.,Tsinghua University,beijing 100084,{3. department of materials Science Harbin Engineering University Harbin China department of Mechanical engineering Tsinghua University Beijing China

Polarizable electrodes of electric double layer capacitors(EDLCs) were made from carbon nanotubes(CNTs).Effect of carbon dioxide activation together with acid oxidation for the electrodes on the characteristics and performances of electrodes and EDLCs was *** dioxide activation changed the microstructure of the electrodes,increased the effective surface area of CNTs and optimized the distribution of apertures of the *** oxidization modified the surface characteristics of *** on the polarizable electrodes treated by carbon dioxide activation and acid oxidization,the performances of EDLCs were greatly *** specific capacitance of the electrodes with organic electrolyte was increased from 2..8 F/g to 60.4 F/g.

关键词： carbon nanotube electric double layer capacitor scan electron microscopy

Distinguishing malignant from normal stomach tissues and its in vivo, in situ measurement in operating process using FTIR Fiber-Optic techniques

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Science china Chemistry 2005年第2期48卷 167-175页

作者： XU Yizhuang1, YANG Limin1, XU Zhi3. ZHAO Ying2. LING Xiaofeng3. LI Qingbo1, WANG Jiansheng4, ZHANG Nengwei3. ZHANG Yuanfu1 & WU Jinguang1 1. The State Key Laboratory of Rare Earth materials and Applications, College of Chemistry and Molecular engineering, Peking University, {2. 100871,{3. 2. Institute of Chemistry, Chinese Academy of Sciences, {2. 100080,{3. 3. department of Surgery, Third Hospital, Peking University, {2. 100083.{3. 4. department of Oncology Surgery, the First Hospital of Xi’an Jiaotong University, Xi’an 710061,{3. Correspondence should be addressed to Wu Jinguang (email: wujg@***) The State Key Laboratory of Rare Earth materials and Applications College of Chemistry and Molecular Engineering Peking University Beijing China department of Surgery Third Hospital Peking University Beijing China Institute of Chemistry Chinese Academy of Sciences Beijing China department of Oncology Surgery the First Hospital of Xi’an Jiaotong University Xi’an China

Gastric tissue samples were studied using mid-IR fiber-optic attenuated total reflectance (ATR) spectroscopy. FTIR spectra of 90 tissue samples from 48 patients, including 3.0}normal and 58 malignant tissue samples, were chosen as examples. Malignancy was usually characterized by the absence of CH and C=O bands, a weak amide II band near 1545 cm-1, a shift of the amide I band to lower wave number, a decrease in the ～1450 cm-1 peak to less than the～1400 cm-1 peak. Subtraction spectra indicate that the amide I and amide II bands of normal and malignant tissues have larger differences in peak positions and relative intensities. The statistical analysis results confirm this conclusion. The results indicate that FTIR fiber optic techniques provide important information about cancerous tissue of the stomach, which can be used to differentiate the malignant tissue from the normal tissue. Based on the above results we successfully realize the detection of the tumor tissues of digestive tract in vivo and in situ. And the results of detection cancer near operating room and in vivo and in situ in the operating room are consistent with the conclusions for the samples stored in liquid N2. which is the basis for the clinical application.

关键词： FTIR, Fiber-Optics, stomach tissues, cancer, diagnosis.

Discrete Element Modeling of Asphalt Concrete Cracking Using a User-def ined Three-dimensional Micromechanical Approach

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Journal of Wuhan University of Technology(materials Science) 2011年第6期26卷 1215-1221页

作者：陈俊 College of Civil and Transportation engineering Hohai University

We established a user-defined micromechanical model using discrete element method （DEM） to investigate the cracking behavior of asphalt concrete （AC）. Using the ＂Fish＂ language provided in the particle flow code in 3.Demensions （PFC3.）, the air voids and mastics in asphalt concrete were realistically built as two distinct phases. With the irregular shape of individual aggregate particles modeled using a clump of spheres of different sizes, the three-dimensional （3.） discrete element model was able to account for aggregate gradation and fraction. Laboratory uniaxial complex modulus test and indirect tensile strength test were performed to obtain input material parameters for the numerical simulation. A set of the indirect tensile test were simulated to study the cracking behavior of AC at two levels of temperature, i e, -10 ℃ and 15 ℃. The predicted results of the numerical simulation were compared with laboratory experimental measurements. Results show that the 3. DEM model is able to predict accurately the fracture pattern of different asphalt mixtures. Based on the DEM model, the effects of air void content and aggregate volumetric fraction on the cracking behavior of asphalt concrete were evaluated.

关键词： discrete element method asphalt concrete cracking behavior three-dimensional simulation micromechanics

Experimental study on bed-load sediment transport under irregular wave and current combined flow

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Acta Oceanologica Sinica 2001年第2期20卷 271-280页

作者： Wu Yongsheng,Qin Chongren (1. department of Hydraulic engineering, Tsinghua University, {2. 100084,{3. 2. School of Civil engineering, Tianjin University, Tianjin 3.0072.{3.) department of Hydraulic engineering Tsinghua University Beijing 100084 China

Using an irregularly oscillating tray and flume, a series of experiments are completed to evaluate bed-load sediment transport rate under irregular wave -current coexistent field. Testing conditions include three interaction angles 0', 45', 90' and two kinds of median sizes (0.3. and 1.10 mm). The results of transport rate show that the net sediment transport rate can be expressed approximately as the function of the maximum bottom shear stress of waves, mean shear stress of current and the grain size.

关键词： Irregular wave-current bed-load transport rate

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.{3. 2. {2. of Physics, {3. Normal University, beijing 100875,{3. 3. High Energy Physics Institute, the Chinese Academy of Sciences, {3. 100080,{3. 4. Archaeology Research Institute, Shanxi Province, Xian 710000,{3. 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—13.8 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

Numerical simulation of air-water two-phase flow over stepped spillways

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Science china(Technological Sciences) 2006年第6期49卷 674-684页

作者： CHENG Xiangju1, CHEN Yongcan1 & LUO Lin2.1. department of Hydraulic engineering, Tsinghua University, {2. 100084,{3. 2. State Key Laboratory of Hydraulics and Mountain River engineering, Sichuan University, Chengdu 610065,{3. department of Hydraulic engineering Tsinghua University Beijing China State Key Laboratory of Hydraulics and Mountain River engineering Sichuan University Chengdu China

Stepped spillways for significant energy dissipation along the chute have gained interest; popularity among researchers; dam engineers. Due to the complexity of air-water two-phase flow over stepped spillways, the finite volume computational fluid dynamics module of the FLUENT software was used to simulate the main characteristics of the flow. Adopting the RNG k- turbulence model, the mixture flow model for air-water two-phase flow was used to simulate the flow field over stepped spillway with the PISO arithmetic technique. The numerical result successfully reproduced the complex flow over a stepped spillway of an experiment case, including the interaction between entrained air bubbles; cavity recirculation in the skimming flow regime, velocity distribution; the pressure profiles on the step surface as well. The result is helpful for understanding the detailed information about energy dissipation over stepped spillways.

关键词： stepped spillway, mixture model, RNG k-εmodel, air-water two-phase flow.