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Reinforcing epoxy resin with nitrogen doped carbon nanotube:A potential lightweight structure material

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Journal of Materials Science & Technology 2018年第11期34卷 2205-2211页

作者： Qi Wang Guodong Wen Junnan Chen dang sheng Su School of Materials Science and Engineering University of Science and Technology of China Institute of Metal Research Chinese Academy of Sciences

The outstanding mechanical properties of nanocarbon materials, especially carbon nanotube（CNT）, make them one of the most promising reinforcing nanofillers for the high-performance lightweight structural material. However, the complicated but not eco-friendly surface functionalization processes（e.g. HNO3 oxidation） are generally necessary to help disperse nanocarbon materials into epoxy or build chemical bonds between them. Herein, nitrogen doped carbon nanotube（NCNT） was used to replace CNT to reinforce the epoxy resin, and the mechanical properties of the NCNT/epoxy nanocomposite showed significant superiorities over the CNT/epoxy nanocomposites. The fabrication process was simple and environmentally friendly, and avoided complicated, polluting and energy intensive surface functionalization processes. Moreover, the NCNT/epoxy suspension exhibited a relative low viscosity, which was favorable for the subsequent application. The reinforcing mechanism of NCNT was also proposed. The present work gives out an easy solution to the preparation of a high-performance nanocomposite as a potential lightweight structure material.

关键词： Epoxy-matric nanocomposite Nitrogen doped carbon nanotube NCNT/epoxy Mechanical properties Toughness

Design,fabrication and kinematics of a bio-inspired robotic bat wing

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Science China(Technological Sciences) 2016年第12期59卷 1921-1930页

作者： YIN Dong Fu ZHANG zhi sheng School of Mechanical Engineering Southeast University

The current work is oriented toward the development of a novel biologically inspired bat aerial robot with morphing wings. Based on the flight characteristics data of natural bats(Eptesicus fuscus), a novel four degrees of freedom robotic bat wing was developed to emulate the movements of bat wing. The design, fabrication, programing and wind tunnel experiments of the robot bat wing are described in this paper. Based on this robotic wing, the influence of flap amplitude, wind speed, flight frequency, downstroke ratio and stroke plane angle as well as the contributions of flap, elbow, sweep and wrist motions on the aerodynamic force and mechanical power were studied and analyzed. Results of wind tunnel experiments validated that higher lift would bring greater power consumption, and the flap motion would generate the most force and need more energy expenditure compared with other motions of bat. The experimental results suggest that the flap and fold motions are indispensable to make a robotic bat wing that has a better flight performance. This study provides some implications and a better understanding for the future robotic bat.

关键词： bio-inspiration wing robotic bat flight kinematics wrist motion

RMAC： A Reliable MAC Protocol Supporting Multicast for Wireless Ad Hoc Networks

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Journal of Computer Science & Technology 2005年第5期20卷 702-712页

作者： Wei-sheng Si Cheng-zhi Li School of Software Dalian University of Technology P.R. China Department of Computer Science and Engineering University of Texas at Arlington U.S.A.

This paper presents a new reliable MAC protocol called “RMAC”supporting reliable multicast for wireless ad hoc networks. By utilizing the busy tones to realize the multicast reliability, RMAC has three novelties：（1） it uses a variablelength control frame to stipulate an order for the receivers to respond, thus solving the feedback collision problem; （2） it extends the usage of busy tone for preventing data frame collisions into the multicast scenario; and （3） it introduces a new usage of busy tone for acknowledging data frames positively. In addition, RMAC is generalized into a comprehensive MAC protocol that provides both reliable and unreliable services for all the three modes of communications： unicast, multicast, and broadcast, making it capable of supporting various upper-layer protocols. The evaluation shows that RMAC achieves high reliability with very limited overhead. RMAC is also compared with other reliable MAC protocols, showing that RMAC not only provides higher reliability but also involves lower cost.

关键词： wireless ad hoc network medium access control reliable multicast busy tone

Watershed protection and landscape enhancement by utilization of river water

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Journal of Environmental Sciences 2003年第4期15卷 487-493页

作者： HUDe-zhi PEIYuan-sheng LUANZhao-kun ResearchCenterforEco-EnviromentalSciences ChineseAcademyofSciencesBeijing100085China InstituteofEnvironmentalSciencesandEngineering LanzhouJiaotongUniversityLanzhou730070China

A scheme for watershed protection and landscape enhancement(WPLE) by utilization of river water was proposed to renovate water resources and protect ecological environment in Qiongshan City, Hainan Province, China. Utilization of river water may diminish the drought and flood risks. The scheme is beneficial to solve the problems of water resources shortage, groundwater declines and saltwater intrusion in the watershed. The object of the WPLE scheme is to achieve a sustainable integrated development of environment, ecology, economy and society. A kind of physically beautiful and functionally vivid landscape may exert its synthetical function on the diversity of landscape and the enjoyment of inhabitants. Feasibility of the scheme will be demonstrated by more experiments and tests, as well as observations in a long term.

关键词： watershed landscape water resources eco environment

碳材料表面活性基团对苯甲醇氧化催化性能的调控研究

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现代化工 2025年第1期45卷 131-136页

作者：陈志佳王盛杨本群杨慧敏内蒙古科技大学化学与化工学院内蒙古包头014000 天水师范学院化学工程与技术学院甘肃天水741000

采用硝酸对生物质基活性炭进行改性处理引入含氧基团(SOGs),研究了碳材料表面官能团对催化苯甲醇氧化反应性能的调控作用。通过SEM、XRD、XPS等对制备的催化剂进行表征,考察了硝酸浓度对活性炭表面氧化基团的影响。结果表明,当用浓度为1... 详细信息

采用硝酸对生物质基活性炭进行改性处理引入含氧基团(SOGs),研究了碳材料表面官能团对催化苯甲醇氧化反应性能的调控作用。通过SEM、XRD、XPS等对制备的催化剂进行表征,考察了硝酸浓度对活性炭表面氧化基团的影响。结果表明,当用浓度为1.5 mol/L的HNO_(3)处理活性炭时,煅烧后所得催化剂AC-1.5催化苯甲醇氧化反应的转化率为94%,选择性为99%,使用5次后仍保持活性,这主要与AC-1.5中羰基含量高有直接关系。该研究结果为开发高效、低成本的生物质基催化剂提供参考。

关键词：活性炭含氧基团羰基催化氧化

Synthesis and properties of physically crosslinked poly (vinyl alcohol) hydrogels

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Journal of China University of Mining and Technology 2008年第2期18卷 271-274页

作者： MA Ru-yin XIONG dang-sheng Department of Materials Science ＆ Engineering Nanjing University of Science and Technology Nanjing Jiangsu 210094 China

The present study is an investigation of the properties of poly(vinyl alcohol),which would be a better contact lens mate- rial than conventional HEMA in some ways.A transparent PVA hydrogel was prepared from a PVA solution in a mixed solvent consisting of water and a water-miscible organic solvent,DMSO,by the freezing-thawing *** water content,visible light transmittance,mechanical and swelling properties of the hydrogels were evaluated as a function of PVA concentration and number of freeze-thaw *** results show that the properties of PVA hydrogels depend on the polymer concentration,the number of freeze-thaw cycles and the addition of the organic solvent.

关键词： poly (vinyl alcohol) hydrogel freezing-thawing method swelling property

Preparation and Application of a Nanocomposite (MPNS/SMA) in Leather Making

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Chinese Chemical Letters 2005年第10期16卷 1409-1412页

作者： Hui PAN zhi Jun ZHANG Hong Xin dang State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 Lab. of Special Functional Material Henan University Kalfeng 475001

A nanocomposite of MPNS/（Styrene-maleic anhydride） was prepared by the polymerization of methacryloxypropyl nano SiO2 （MPNS）, styrene （ST） and maleic anhydride （MA） with benzoyl peroxide （BPO） as initiator in toluene. The prepared samples were characterized by Fourier transform infrared spectroscopy （PT-IR） and transmission electron microscope （TEM）. Meanwhile, the nanocomposite was applied as a tanning agent in leather making and the results showed that leather treated with MPNS/SMA nanocomposite has excellent quality.

关键词： Nano-sized SiO2 composite polymerization tanning agent.

Effect of Counterface Material on Friction and Wear Behavior of Ni-Cr-W-Al-Ti-MoS_2 Composites

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Chinese Journal of Aeronautics 2006年第B12期19卷 74-77页

作者： LI Jian-liang XIONG dang-sheng WAN Yi Department of Materials Science and Engineering Nanfing University of Science and Technology Nanjing 210094 China

Ni-Cr-W-Al-Ti-MoS2 self-lubricating composites were prepared through the powder metallurgy （P/M） method. Their friction properties were investigated by a pin-on-disk tribometer in the range from the room temperature to 600 ℃. Alumina, silicon nitride and nickel-iron-sulfide alloys were selected as the counterface materials. Results indicate that the lowest friction coefficients under 0.22 can be obtained at 600℃ when rubbed against alumina. When rubbed against nickel-iron-sulfide alloys, are presented the lowest wear rates in the magnitude of 10^-6 mm^3/N-m, one order of magnitude lower than those when rubbed against ceramics. In the case of three rubbing pairs, the wear rates of the composite containing MoS2 present themselves inversely proportional to friction coefficients. With alumina ceramics used as a counterface, transfer films and glaze layers will form on the contact surface playing a main role in lubrication at high temperatures. However, when silicon nitride and nickel-iron-sulfide alloy are used, the lubricating transfer films appear not to be prominent.

关键词： powder metallurgy (P/M) high temperature solid lubrication Ni-based composite

A Compact System of Capacitively Coupled Contactless Conductivity Detection Based on the Square Wave Excitation Signal for Capillary Electrophoresis

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Chinese Chemical Letters 2006年第9期17卷 1229-1232页

作者： Shui Feng ZHANG Li Shi WANG zhi dang College of Environmental Science and Engineering South China University of Technology Guangzhou 510640

This paper reported a compact system of capacitively coupled contactless conductivity detection （C4D） based on the square wave excitation voltage for capillary electrophoresis, and it exhibited excellent sensitivity at the optimal frequency of 198 kHz. The feasibility and sensitivity of this detector was demonstrated by simultaneous detection of thirteen ions including alkali, alkaline earth and heavy metal ions. And the detection limits （S/N 3） were in the range of 0.2-1μmol/L for Mn^2＋, K^＋, Na^＋, Mg^2＋, Ca^2＋, Li^＋, Ba^2＋, and 7-25 μmol/L for Ni^2＋, Cu^2＋, Cd^2＋, Pb^2＋, Co^2＋, Zn^2＋.

关键词： Capillary electrophoresis square wave excitation signal contactless conductivitydetector metal ions.