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Miniature Boat Fabrication with Striking Loading Capacity in Seawater from Hydrophobic Steel Mesh

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Chinese Journal of Chemical Physics 2015年第6期28卷 -页

作者： Zai-xing jiang Ming-qiang Wang Hao cheng Hai-bao Lv Yong-tao Yao Yong-ping Bai Lu Shao Department of Polymer Science and Technology School of Chemical Engineering and TechnologyHarbin Institute of Technology Harbin 150001 China Science and Technology on Advanced Composites in Special Environments Laboratory Harbin Institute of Technology Harbin 150080 China

A superhydrophobic steel mesh film was prepared by combination of macro-scale rough surface and low surface energy material treatment through a facile coating method. The contact angle for seawater is measured to be as high as 130.16°. A reformed Cassie-Baxter equation was applied for the theoretical predictions of this novel material for the first time. Good agreement between the predictions and experiments was obtained. The loading capacities of these boats, fabricated from the resulting hydrophobic steel meshes, were also characterized. The highest loading weight about 17.50 g was obtained by the steel mesh treated by 2.0wt% (heptadecafluoro-1,1,2,2,-tetradecyl)trimethoxysilane solution. The striking loading capacity of this miniature boat may be attributed to the air film trapped around the mesh surface. This novel superhydrophobic steel mesh material have wide applications on medical materials, marine materials and smart materials.

关键词： Hydrophobic Steel mesh Loading capacity

Multi-channel blind deconvolution algorithm for multiple-input multiple-output DS/CDMA system

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Journal of Systems Engineering and Electronics 2007年第3期18卷 454-461页

作者： cheng Hao Guo Wei jiang Yi National Key Lab of Communication Univ. of Electronic Science and Technology Chengdu 610054 P. R. China

Direct sequence spread spectrum transmission can be realized at low SNR, and has low probabilityof detection. It is aly problem how to obtain the original users＇ signal in a non-cooperative context. In practicality, the DS/CDMA sources received are linear convolute mixing. A more complex multichannel blind deconvolution MBD algorithm is required to achieve better source separation. An improved MBD algorithm for separating linear convolved mixtures of signals in CDMA system is proposed. This algorithm is based on minimizing the average squared cross-output-channel-correlation. The mixture coefficients are totally unknown, while some knowledge about temporal model exists. Results show that the proposed algorithm can bring about the exactness and low computational complexity.

关键词： DS/CDMA signal non-cooperative MBD stochastic gradient algorithms for MBD.

Personal Review:Progress and prospect in electro-Fenton process for wastewater treatment

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第7期8卷 1118-1125页

作者： jiang cheng-chun ZHANG Jia-fa School of Civil and Environmental Engineering Shenzhen Polytechnic Shenzhen 518055 China College of Civil Engineering Huaqiao University Quanzhou 362021 China

As a novel advanced oxidation process (AOP), electro-Fenton process is powerful for degrading most organic compounds including toxic and non-biodegradable ones, and so has attracted great attention. This paper reviews this process in detail including the mechanism, electrolytic bath, electrode materials, aerations and operation parameters. The application of electro-Fenton method in wastewater treatment is evaluated and summarized. Future work in this field is suggested, and three main directions of new electrode exploitation, development of assisted technologies and mechanistic study should be strengthened.

关键词： Electro-Fenton Hydroxyl radicals Advanced oxidation process (AOP) Refractory wastewater

Achieving p-type conductivity in ZnO/Bi_(0.5)Sb_(1.5)Te_(3) composites

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Journal of Energy Chemistry 2021年第2期30卷 163-167,I0006页

作者： Li Yin Lin Sun Peng jiang Xinhe bao State Key Laboratory of Catalysis CAS Center for Excellence in NanoscienceDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina University of Chinese Academy of Sciences Beijing J00049China

With the rapid exhaustion of fossil energy, the demand for clean and renewable energy is urgently growing. Thermoelectric(TE) materials, which can directly convert waste heat into electrical energy, are attracting gre... 详细信息

关键词： ZnO Achieving p-type conductivity in ZnO/Bi Te_(3)composites

A new principle and device for large aircraft components gaining accurate support by ball joint

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第5期12卷 405-414页

作者： bao-gui QIU Jun-xia jiang Ying-lin KE The State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

How to obtain an accurate support for large components by ball joint is a key process in aircraft digital assembly. A novel principle and device is developed to solve the problem. Firstly, the working principle of the device is introduced. When three or four displacement sensors installed in the localizer are touched by the ball-head, the spatial relation is calculated between the large aircraft component's ball-head and the localizer's ball-socket. The localizer is driven to achieve a new position by compensation. Relatively, a support revising algorithm is proposed. The localizer's ball-socket approaches the ball-head based on the displacement sensors. According to the points selected from its spherical surface, the coordinates of ball-head spherical center are computed by geometry. Finally, as a typical application, the device is used to conduct a test-fuselage's ball-head into a localizer's ball-socket. Positional deviations of the spherical centers between the ball-head and the ball-socket in the x, y, and z directions are all controlled within ±0.05 mm under various working conditions. The results of the experiments show that the device has the characteristics of high precision, excellent stability, strong operability, and great potential to be applied widely in the modern aircraft industry.

关键词： Aircraft digital assembly Large aircraft component Accurate support Ball joint Displacement sensor Three coordinate numerical control localizer

Performance of Polyaniline-coated Short Carbon Fibers in Electromagnetic Shielding Coating

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Journal of Materials Science & Technology 2007年第4期23卷 529-534页

作者： Dongxiu YU jiang cheng Zhuoru YANG School of Chemical and Energy Engineering South China University of Technology Guangzhou 510640 China

Combined nitric acid oxidation method and polyaniline （PANI）-coated method were applied to modify the surface properties of short carbon fibers （SCF）. The electrical and mechanical properties of acrylic coatings with 50 wt pct PANI-coated carbon fiber were investigated by using scanning electron microscope （SEM）, UV-Vis spectrophotometer, four-probe method and the coaxial cable method. The results of the pH measurement and XPS （X-ray photoelectron spectroscopy） patterns showed that the oxygen functional groups, such as -OH and -COOH, were attached on the carbon fiber surfaces after oxidation treatment. The XPS analysis of PANl-coated oxidized SCF （PAOSCF） revealed that PANI may bond on the surface of oxidized SCF with chemical bonds. SEM images and surface roughness analyses showed that PANl-coated layer changed the surface morphology. Compared with SCF/acrylic coating, the surface resistivity of PAOSCF/acrylic coating decreased from17.1 to 5.3 Ω/sq and the shielding efficiency （SE） value increased from 1.54 to 23.3 dB.

关键词： Carbon fibers Polyaniline Surface treatment Dispersion stability Shielding effectiveness

A Nonlinear Small-Gain Theorem for Large-Scale Infinite-Dimensional Systems

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Journal of Systems Science & Complexity 2018年第1期31卷 188-199页

作者： bao Adiya LIU Tengfei jiang Zhong-Ping ZHANG Lina State Key Laboratory of Synthetical Automation for Process Industries Northeastern University Shenyang 110819 China Tandon School of Engineering New York University Brooklyn NY 11201 USA

This paper develops a large-scale small-gain result for dynamic networks composed of infinite-dimensional subsystems. It is assumed that the subsystems are input-to-output stable（IOS）and unboundedness observable（UO）, and the large-scale infinite-dimensional system can be proved to be IOS and UO if the proposed small-gain condition is satisfied.

关键词： Infinite-dimensional systems input-to-output stability(IOS) input-to-state stability(ISS) small-gain theorem

A surface parametric control and global optimization method for axial flow compressor blades

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Chinese Journal of Aeronautics 2019年第7期32卷 1618-1634页

作者： Jinxin cheng jiang CHEN Hang XIANG School of Energy and Power Engineering Beihang University

An aerodynamic optimization method for axial flow compressor blades available for engineering is developed in this paper. Bezier surface is adopted as parameterization method to control the suction surface of the blades, which brings the following advantages:(A) significantly reducing design variables;(B) easy to ensure the mechanical strength of rotating blades;(C) better physical understanding;(D) easy to achieve smooth surface. The Improved Artificial Bee Colony(IABC) algorithm, which significantly increases the convergence speed and global optimization ability, is adopted to find the optimal result. A new engineering optimization tool is constructed by combining the surface parametric control method, the IABC algorithm, with a verified Computational Fluid Dynamics(CFD) simulation method, and it has been successfully applied in the aerodynamic optimization for a single-row transonic rotor(Rotor 37) and a single-stage transonic axialflow compressor(Stage 35). With the constraint that the relative change in the flow rate is less than0.5% and the total pressure ratio does not decrease, within the acceptable time in engineering, the adiabatic efficiency of Rotor 37 at design point increases by 1.02%, while its surge margin 0.84%,and the adiabatic efficiency of Stage 35 0.54%, while its surge margin 1.11% after optimization, to verify the effectiveness and potential in engineering of this new tool for optimization of axial compressor blade.

关键词： Aerodynamic optimization Bezier surface Compressor Global optimization Surface parametric control

Design and simulation of fault diagnosis based on NUIO/LMI for satellite attitude control systems

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Journal of Systems Engineering and Electronics 2012年第4期23卷 581-587页

作者： Yuehua cheng Qian Hou Bin jiang College of Automation Engineering Nanjing University of Aeronautics and Astronautics Nanjing 210016 R R. China Academy of Frontier Science Nanjing University of Aeronautics and Astronautics Nanjing 210016 P. R. China

This paper presents a scheme of fault diagnosis for flexible satellites during orbit maneuver. The main contribution of the paper is related to the design of the nonlinear input observer which can avoid false alarm arising from the disturbance from orbit control force. The effects of orbit control force on the fault diagnosis system for satellite attitude control systems, including the disturbing torque caused by the misalignments and the model uncertainty caused by the fuel consumed, are discussed, where standard Lu- enberger observer cannot work well. Then the nonlinear unknown input observer is proposed to decouple faults from disturbance, Besides, a linear matrix inequality approach is adopted to reduce the effect of nonlinear part and model uncertainties on the observer. The numerical and semi-physical simulation demonstrates the effectiveness of the proposed observer for the fault diagnosis system of the satellite during orbit maneuver.

关键词： orbit control flexible satellite attitude control system,nonlinear unknown input observer (NUIO) fault diagnosis.