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Study of Laser Lap Welding of SUS301L Austenitic Stainless Steel Using Optimal Design Method

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稀有金属材料与工程 2011年第S4期40卷 63-67页

作者： Liu Jia,Shi Yan,Zhang Hong school of Electromechanical Engineering,{2.,changchun 13002.,china changchun Univ Sci & Technol Sch Electromech Engn Changchun 130022 Peoples R China

This paper presents an experimental design approach to process parameter optimization for the laser lap welding of SUS301L austenitic stainless steels using Nd:YAG laser in order to reduce the welding deformations of the back of the welding seams while ensuring mechanical properties of welding *** determine the optimal laser-welding parameters,a set of mathematical models were developed relating welding parameters to each of the weld *** were validated both statistically and *** order to reduce experimental error and the number of specimens,the part of orthogonal experiments were used in this *** quality criteria set for the weld to determine optimal parameters were the maximization of weld width and the minimization of weld *** power,welding speed,the laser irradiation angle,the focused distance and shield gas of 3.5kW,7.0m/min,70°,0mm and N2.with the flow of 30L/min,respectively,with a fiber diameter of 600μm were identified as the optimal set of process parameters.

关键词： laser lap welding sus301l austenitic stainless steel welding deformation orthogonal experiments

The study of adsorption gas sensor based carbon nanotube film

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science china(Technological sciences) 2005年第4期48卷 372-384页

作者： LI Xin1, LIU Junhua2.& ZHU changchun1 1. school of {2. and Information Engineering, Xi’an Jiaotong university, Xi’an 710049, china 2. school of Electric Engineering, Xi’an Jiaotong university, Xi’an 710049, china 1. school of electronic and Information Engineering Xi’an Jiaotong University 710049 Xi’an China 2. school of Electric Engineering Xi’an Jiaotong University 710049 Xi’an China

The study of gas sensitivity of multi-wall carbon nanotubes (MWNTs), which is deposited by low press chemical vapor deposition (LPCVD), is presented. The results show that the pure MWNTs are not sensitive to the gases measured, while the composite film consisting of the MWNTs and silicon dioxide is sensitive to the methane, the hydrogen and the acetylene. The MWNTs and silicon dioxide composite film have the capacitance characteristic because of the formation of Schottky junctions within the MWNTs. The chemistry adsorption of the gas measured on the surface of the MWNTs affects the space discharge area of the Schottky junction, so that the dielectric constant changes with the gas concentration. That is why the gas is sensed.

关键词： gas sensor, carbon nanotubes, low press chemical vapor deposition, scatter.

Boosting photocatalytic hydrogen evolution enabled by SiO_(2.-supporting chiral covalent organic frameworks with parallel stacking sequence

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Chinese Journal of Catalysis 2024年第9期64卷 87-97页

作者： Zheng Lin Wanting Xie Mengjing Zhu changchun Wang Jia Guo State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China

Two-dimensional covalent organic frameworks(2. COFs)feature extendedπ-conjugation and ordered stacking sequence,showing great promise for high-performance *** atomic frameworks of 2. COFs facilitate the in-plane photogenerated charge transfer,but the precise ordered alignment is limited due to the non-covalentπ-stacking of COF layers,accordingly hindering out-of-plane transfer ***,we address a chiral induction method to construct a parallelly superimposed stacking chiral COF ultrathin shell on the support of SiO_(2. *** to the achiral COF analogues,the chiral COF shell with the parallel AA-stacking structure is more conducive to enhance the built-in electric field and accumulates photogenerated electrons for the rapid migration,thereby affording superior photocatalytic performance in hydrogen evolution from water *** the simplest ketoenamine-linked chiral COF as a shell of SiO_(2. particle,the resulting composite exhibits an impressive hydrogen evolution rate of 107.1 mmol g^(-1)h^(-1)along with the apparent quantum efficiency of 14.31%at 475 ***,the composite photocatalysts could be fabricated into a film device,displaying a remarkable photocatalytic performance of 178.0 mmol m^(-2.h^(-1)for hydrogen *** work underpins the surface engineering of organic photocatalysts and illustrates the significance of COF stacking structures in regulating electronic properties.

关键词： Covalent organic framework Photocatalysis Hydrogen generation Chiral induction Core-shell structure

Using multi-matching system based on a simplified deformable model of the human iris for iris recognition

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Journal of Bionic Engineering 2004年第3期1卷 183-190页

作者： MING Xing , XU Tao , WANG Zheng-xuan 1 2.3 1. College of Computer science and technology, Nanling Campus,Jilin {2., 5988 Renmin Street,changchun 13002., P. R. china 2. College of mechanical science and Engineering, Nanling Campus,Jilin {2., 5988 Renmin Street, changchun 13002., P. R. china 3. College of Computer science and technology, Qianwei Campus,Jilin {2., 10 Qianwei Road, changchun 130012. P. R. china. Jilin university Jilin university Jilin university

A new method for iris recognition using a multi-matching system based on a simplified deformable model of the human iris was proposed. The method defined iris feature points and formed the feature space based on a wavelet transform. In the matching stage it worked in a crude manner. Driven by a simplified deformable iris model, the crude matching was refined. By means of such multi-matching system, the task of iris recognition was accomplished. This process can preserve the elastic deformation between an input iris image and a template and improve precision for iris recognition. The experimental results indicate the va- lidity of this method.

关键词： iris recognition wavelet transform feature points deformable model

Fabrication and Characterization of Nano Silver Powder Prepared by Spray Pyrolysis

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Journal of Wuhan university of technology(Materials {2.) 2009年第6期24卷 871-874页

作者：章桥新 school of mechanical and {2. Engineering Wuhan University of Technology State Key Laboratory of Advanced technology for Materials Synthesis & Processing Wuhan University of Technology

Silver powder was fabricated by spray pyrolysis, using 2.-2.% AgNO3 solution, 336-500 mL/h flux of AgNO3 solution, 0.2.-0.32.MPa flux of carrier gas and in the 62.-82. ℃ temperature range. The effects of furnace set temperature, concentration of AgNO3 aqueous solution, flux of AgNO3 aqueous solution as well as carrier gas on the morphology and particle size distribution of silver powder, were investigated. The experimental results showed that with the high concentration of AgNO3 aqueous solution, the average grain size of silver decreased with the increasing of furnace set temperature. But the gain size distribution was not homogenous, the discontinuous grain growth occurred. With the low concentration of AgNO3 aqueous solution, the higher furnace set temperature made the nano sliver grains sintered together to grow. Nano silver powder about 100 nm was fabricated by spray pyrolysis, using 2.t% AgNO3 solutions, 336 mL/h flux of AgNO3 aqueous solution, 0.32.MPa flux of carrier gas at 72. ℃ furnace set temperature.

关键词： nano silver powder fabrication characterization spray pyrolysis

Bionic Design and Finite Element Analysis of Elbow in Ice Transportation Cooling System

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Journal of Bionic Engineering 2010年第3期7卷 301-306页

作者： Dejun Miao~(1,2., Xiuhua Sui~3, Linjing Xiao~3 1. Key Laboratory of Mine Hazard Prevention and Control (Ministry of Education, china), Shandong university of {2. and technology, Qingdao 2.6510, P. R. china 2. school of Architecture, Tsinghua university, Beijing 100084, P. R. china 3. College of mechanical and electronic Engineering, Shandong university of {2. and technology, Qingdao 2.6510, P. R. china [a] Key Laboratory of Mine Hazard Prevention Control (Ministry of Education China) Shandong University of Science technology Qingdao 266510 P. R. China [b] School of Architecture Tsinghua University Beijing 100084 P. R. China [c] College of Mechanical electronic Engineering Shandong University of Science technology Qingdao 266510 P. R. China

With the increase in mining depth, mine heat harm has appeared to be more prominent. The mine heat harm could be resolvedor reduced by ice refrigeration. Thus, ice transportation through pipeline becomes a critical problem; typically flowresistance occurs in the elbow. In the present study, according to the analysis of the surface morphology of fish scale, abiomimetic functional surface structure for the interior wall of elbow is designed. Based on the theory of liquid-solid two phaseflow, a CFD numerical simulation of ice-water mixture flowing through the elbow is carried out using finite element *** experiments of pressure drop and flow resistance for both bionic and common elbows are conducted to test theeffect of the bionic elbow on flow resistance reduction. It is found that with the increase in the ice mass fraction in the ice-watermixture, the effect of bionic elbow on resistance reduction becomes more obvious.

关键词： bionic elbow two phase flow ice transportation flow resistance reduction pressure loss

Digital Design of Virtual Prototype based on Multidisciplinary Design Optimization

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武汉理工大学学报 2006年第S2期28卷 728-733页

作者： WU Baogui~1 HUANG Hongzhong~2.TAO Ye~1 1.school of mechanical Engineering,Dalian {2. of technology,Dalian 11602.,china, 2.school of Mechatronics Engineering,{2. of electronic science and technology of china,Chengdu 610054,china school of mechanical Engineering Dalian University of TechnologyDalian 116023China school of Mechatronics Engineering University of Electronic Science and Technology of ChinaChengdu 610054China

In order to obtain digital design of complex mechanical product as optimal as possible in an efficient way,multi- discipline integrated design method is proposed,which integrates multidisciplinary design optimization (MDO) into digital design process to design virtual prototype (VP) *** combining MDO and multi-body system dynamics,MDO integra- tion platform,which takes VP as the core,is *** automated MDO design of VP is realized and changes of mechani- cal design project can be expressed intuitively during MDO design *** proposed approach is also demonstrated by using inte- grated analyzing flow of vehicle engineering *** result shows that the method not only can feasibly realize the MDO of VP, but also can solve the optimization problem of vehicle multi-body system dynamic *** can be adopted to the digital de- sign of other complex system.

关键词： complex mechanical product virtual prototype digital design multidiscipline design optimization integration platform vehicle design

Photocatalytic Degradation of Rhodamine B Dye with High Purity Anatase Nano-TiO_2.Synthesized by a Hydrothermal Method

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Journal of Wuhan university of technology(Materials {2.) 2011年第4期26卷 600-605页

作者：史晓亮 school of mechanical and {2. Engineering Wuhan University of Technology State Key Laboratory of Advanced technology for Materials Synthesis & Processing Wuhan University of Technology

High purity anatase nano-TiO2.powders with high photocatalytic activity were prepared by a hydrothermal synthesis method. X-ray diffraction （XRD）, field emission transmission electron microscopy （FETEM）, ultraviolet-visible （UV-Vis） light absorption spectrum and photoluminescence （PL） spectrum were adopted to characterize the catalyst. Effects of temperature, time and sol concentration of hydrothermal synthesis on particle size and phases were investigated. Photocatalytic activities in the degradation of Rhodamine B Dye were studied. The experimental results indicated that photocatalytic activity of the nano-TiO2.powers was much higher than that of P2. （Degussa）.

关键词： TiO2 hydrothermal synthesis photocatalytic activity high purity anatase

Theoretical analysis of alloy multiplying factor by the empirical electron theory of solids and molecules

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science china(Technological sciences) 2007年第6期50卷 807-814页

作者： SONG YuePeng1,2. LIU GuoQuan2. LI ZhiLin3, FENG ChengMing1 1 mechanical and electronic Engineering College, Shandong Agricultural {2., Tai’an 2.1018, china 2.College of Materials science and Engineering, {2. of science and technology, Beijing 100083, china 3 College of Material science and Engineering, Beijing {2. of Chemical technology, Beijing 10002., china mechanical electronic Engineering College Shandong Agricultural University Tai’an 271018 China College of Materials science Engineering University of Science technology Beijing 100083 China College of Material science Engineering Beijing University of Chemical Technology Beijing 100029 China

By introducing the distribution probability of structural units in austenite contain- ing alloying elements and considering its effects on phase transformation, this paper establishes a calculation model of distribution probability of structural units. A new valence electron structure (VES) parameter-transformation effect coefficient of alloying elements (HL), is defined and then studied both theoretically and ex- perimentally. The relationship between the parameter HL and the multiplying factor (the quenching capability factor) of alloying elements is studied. The results indi- cate that the two parameters (HL and the quenching capability factor) have the same variation characteristic and substance feature. Therefore, the multiplying factor virtually expresses the relative quantity of structural units in the alloying elements-containing austenite.

关键词： multiplying factor (the quenching capability factor), empirical electron theory of solids and molecules, transformation effect coefficient of alloying elements, structural units in austenite containing alloying elements