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Acta Mechanica Solida Sinica 2011年第2期24卷 153-165页

作者： zhongjin wang jianguang liu School of Materials Science and Engineering Harbin Institute of Technology Harbin 150001 China

The present paper is devoted to developing a new numerical simulation method for the analysis of viscous pressure forming （VPF）, which is a sheet flexible-die forming （FDF） process. The pressure-carrying medium used in VPF is one kind of semisolid, flowable and viscous material and its deformation behavior can be described by the visco-elastoplastic constitutive model. A sectional finite element model for the coupled deformation analysis between the viscoelastoplastic pressure-carrying medium and the elastoplastic sheet metal is proposed. The resolution of the Updated Lagrangian （UL） formulation is based on a static explicit approach. The frictional contact between sheet metal and visco-elastoplastic pressure-carrying medium is treated by the penalty function method. Coupled deformation between sheet metal and visco-elastoplastic pressure-carrying medium with large slip is analyzed to validate the developed algorithm. Finally, the viscous pressure bulging （VPB） process of DC06 sheet metal is simulated. Good agreement between numerical simulation results and experimental measurements shows the validity of the developed algorithm.

关键词： viscous pressure forming(VPF) sheet forming sectional finite element analysis coupled deformation visco-elastoplastic pressure-carrying medium

Viscous Inner and Outer Pressure Forming Method of Thin-walled Tube and Its Application

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Journal of Wuhan University of Technology(Materials Science) 2015年第2期30卷 404-407页

作者：高铁军 liu Yang wang zhongjin Faculty of Aerospace Engineering Shenyang Aerospace University School of Materials Science and Engineering Harbin Institute of Technology

Aiming at overcoming the difficulties in integral forming of thin-walled tubes with complex shapes, a novel forming method by inner and outer pressure through viscous was proposed. In this method, by dividing large deformation of the part into inner and outer pressure forming deformations, the limit deformation of tube part can be increased by several times. Meanwhile, the principle of viscous inner and outer pressure forming was provided, and key problems during the forming process such as reduction of the wall-thickness and instability wrinkling were analyzed. Thereby, the complex curved surface super-alloy GH3044 thin-walled tube with varying diameter ratio of 1.35（the ratio between the maximum and minimum diameters of the part） can be integrally formed by this method. The experimental surface of the formed part is superior in quality and the wall-thickness distribution is uniform. The results show that the viscous inner and outer pressure forming can provide a new approach for integral forming of thin-walled tubes with complex shapes.

关键词： thin-walled tube inner and outer pressure forming viscous medium integral forming

Dynamic Resistance and Energy Absorption of Sandwich Beam via a Micro-Topology Optimization

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 146-162页

作者： Shiqiang Li Yuwei Li Xiaomin Ma jianguang Fang Zhifang liu Zhihua wang Institute of Applied Mechanics Taiyuan University of TechnologyTaiyuan 030024China Shanxi Key Laboratory of Material Strength and Structural Impact Taiyuan University of TechnologyTaiyuan 030024China School of Civil and Environmental Engineering University of Technology SydneySydneyNSW 2007Australia

The current research of sandwich structures under dynamic loading mainly focus on the response characteristic of *** micro-topology of core layers would sufficiently influence the property of sandwich ***,the micro deformation and topology mechanism of structural deformation and energy absorption are *** this paper,based on the bi-directional evolutionary structural optimization method and periodic base cell(PBC)technology,a topology optimization frame work is proposed to optimize the core layer of sandwich *** objective of the present optimization problem is to maximize shear stiffness of PBC with a volume *** effects of the volume fraction,filter radius,and initial PBC aspect ratio on the micro-topology of the core were *** dynamic response process,core compression,and energy absorption capacity of the sandwich beams under blast impact loading were analyzed by the finite element *** results demonstrated that the overpressure action stage was coupled with the core compression *** the same loading and mass per unit area,the sandwich beam with a 20%volume fraction core layer had the best blast *** filter radius has a slight effect on the shear stiffness and blast resistances of the sandwich *** increasing the filter radius could slightly improve the bending *** changing the initial PBC aspect ratio,there are three ways for PBC evolution:The first is to change the angle between the adjacent bars,the second is to further form holes in the bars,and the third is to combine the first two ***,not all three ways can improve the energy absorption capacity of the *** the aspect ratio of the PBC arbitrarily may lead to worse *** studies are necessary for further detailed *** research proposes a new topology sandwich beam structure by micro-topology optimization,which has sufficient shear *** micro mechanism of structural

关键词： Topology optimization Sandwich beam Impact loading Dynamic resistance Energy absorption Micro mechanism

FPGA Optimized Accelerator of DCNN with Fast Data Readout and Multiplier Sharing Strategy

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Computers, Materials & Continua 2023年第12期77卷 3237-3263页

作者： Tuo Ma Zhiwei Li Qingjiang Li Haijun liu zhongjin Zhao Yinan wang College of Electronic Science and Technology National University of Defense TechnologyChangsha410073China

With the continuous development of deep learning,Deep Convolutional Neural Network(DCNN)has attracted wide attention in the industry due to its high accuracy in image *** with other DCNN hard-ware deployment platforms,Field Programmable Gate Array(FPGA)has the advantages of being programmable,low power consumption,parallelism,and low ***,the enormous amount of calculation of DCNN and the limited logic capacity of FPGA restrict the energy efficiency of the DCNN *** traditional sequential sliding window method can improve the throughput of the DCNN accelerator by data multiplexing,but this method’s data multiplexing rate is low because it repeatedly reads the data between *** paper proposes a fast data readout strategy via the circular sliding window data reading method,it can improve the multiplexing rate of data between rows by optimizing the memory access order of input *** addition,the multiplication bit width of the DCNN accelerator is much smaller than that of the Digital Signal Processing(DSP)on the FPGA,which means that there will be a waste of resources if a multiplication uses a single DSP.A multiplier sharing strategy is proposed,the multiplier of the accelerator is customized so that a single DSP block can complete multiple groups of 4,6,and 8-bit signed multiplication in ***,based on two strategies of appeal,an FPGA optimized accelerator is *** accelerator is customized by Verilog language and deployed on Xilinx *** the accelerator recognizes the CIRFAR-10 dataset,its energy efficiency is 39.98 GOPS/W,which provides 1.73×speedup energy efficiency over previous DCNN FPGA *** the accelerator recognizes the IMAGENET dataset,its energy efficiency is 41.12 GOPS/W,which shows 1.28×−3.14×energy efficiency compared with others.

关键词： FPGA accelerator DCNN fast data readout strategy multiplier sharing strategy network quantization energy efficient

Nitrification and denitrification in biological activated carbon filter for treating high ammonia source water

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Frontiers of Environmental Science & Engineering 2008年第1期2卷 94-98页

作者： jianguang liu Xiaojian ZHANG Zhansheng wang Department of Environmental Science and Engineering Tsinghua UniversityBeijing 100084China School of Public Works and Environmental Engineering Shandong Jianzhu UniversityJinan 250101China

Since the ammonia in the effluent of the tradi-tional water purification process could not meet the supply demand,the advanced treatment of a high concentration of NH4+-N micro-polluted source water by biological activated carbon filter(BACF)was *** filter was operated in the downflow manner and the results showed that the remov-ing rate of NH_(4)^(+)-N was related to the influent concentration of NH_(4)^(+)-*** removing rate could be higher than 95%when influent concentration was under 1.0 mg/*** could also decrease with the increasing influent concentration when the NH_(4)^(+)-N concentration was in the range from 1.5 to 4.9 mg/L and the dissolved oxygen(DO)in the influent was under 10 mg/L,and the minimum removing rate could be 30%.The key factor of restricting nitrification in BACF was the influent *** the influent NH_(4)^(+)-N concentration was high,the DO in water was almost depleted entirely by the nitrifying and hetetrophic bacteria in the depth of 0.4 m filter and the filter layer was divided into aerobic and anoxic *** nitrification and degradation of organic matters existed in the aerobic zone,while the denitrification occurred in the anoxic *** to the limited carbon source,the denitrifica-tion could not be carried out properly,which led to the accu-mulation of the denitrification intermediates such as NO_(2)^(−).In addition to the denitrification bacteria,the nitrification and the heterotrophic bacteria existed in the anoxic zone.

关键词： biological activated carbon micro-polluted source water nitrification denitrification

AFLP analysis revealed differences in genetic diversity of four natural populations of Manila clam (Ruditapes philippinarum) in China

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Acta Oceanologica Sinica 2007年第1期26卷 150-158页

作者： liu Xiangquan BAO Zhenmin HU Jingjie wang Shi ZHAN Aibin liu Hui FANG jianguang wang Rucai Laboratory of Marine Genetics and Breeding （ MGB） Ocean University of China Qingdao 266003 China Yellow Sea Fisheries Research Institute Chinese Academy of Fishery Science Qingdao 266071 China

The amplified fragment length polymorphism （AFLP） technology was used to analyze the genetic diversities in four natural populations of Manila clam （ Ruditapes philippinarum）, distributed in four sea areas of China, i.e. , the Bohai Sea, the Huanghai Sea, the East China Sea and the South China Sea. Two hundred and sixty-four AFLP loci were analysed in 195 individuals and revealed high levels of genetic diversity. The percentage of polymorphic loci ranged from 92.13% to 96.06% and the Shannon＇ s information index was from 0.256 8 to 0. 275 6. By analyzing molecular variance （ AMOVA）, it was found that there were high levels of genetic differentiation between populations of Qingdao and the other three sea areas. Cluster analysis by Nei＇ s pairwise distances grouped specimens by geographical origin, except the population of Qingdao. A conclusion can be drawn that there are high genetic diversities in the four natural populations of Manila clam in China and some distinct differences existed among and between the four populations. The results also indicated that human cultivation activities will have great influence on the genetic structure of the population of Qingdao.

关键词： Ruditapes philippinarum genetic diversity geographical population AFLP

Rationally designed Ti_(3)C_(2) MXene/CaIn_(2)S_(4) Schottky heterojunction for enhanced photocatalytic Cr(VI) reduction:Performance,influence factors and mechanism

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Journal of Materials Science & Technology 2023年第30期161卷 123-135页

作者： Chao liu Wen Xiao Xingyu liu Qiang wang Jiawei Hu Siyuan Zhang jianguang Xu Qinfang Zhang Zhigang Zou School of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China School of Energy and Materials Shanghai Polytechnic UniversityShanghai 201209China Eco-Materials and Renewable Energy Research Centre(ERERC) Nanjing UniversityNanjing 210093China

As a highly toxic heavy metal,Cr(VI)reduction by developing high-efficiency photocatalysts is of great ***,we firstly design few-layer Ti_(3)C_(2) MXene(FTM)by the hand-operated shaking,show-ing dual advantages of structural stability and more exposed reactive ***,a refluxed process is performed to fabricate FTM/CaIn_(2)S_(4)(FTC) composites,where 2D CaIn_(2)S_(4)(CIS) nanoplates are closely con-nected with 2D FTM to form Schottky *** optimal 1-FTC with the FTM/CIS mass ratio of 1 wt.%exhibits the highest activity toward photocatalytic Cr(VI)reduction under visible *** is well eluci-dated that the broadened light absorption range and promoted charge carrier separation rate induced by the introduction of FTM are responsible for improving photocatalytic activity of *** Cr(VI)photoreduction,1-FTC possesses excellent photo-stability and *** effects of catalyst mass,co-existing ions,water sources and pH values on the Cr(VI)photoreduction efficiency are ***-togenerated•O_(2)^(−)and e−are the main radical species accounting for Cr(VI)photoreduction over *** photocatalytic mechanism along with Cr(VI)removal pathway is *** work may provide some insights into constructing FTM-based Schottky junctions for the efficient water purification.

关键词： CaIn_(2)S_(4) Ti_(3)C_(2)MXene Cr(VI)reduction Visible light Photocatalysis

板材软模成形二维断面有限元分析界面接触摩擦处理

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机械工程学报 2006年第5期42卷 155-159页

作者：王忠金刘建光哈尔滨工业大学材料科学与工程学院哈尔滨150001

板材软模成形是板材和柔性传力介质耦合变形过程,存在板材和刚性模具及板材和柔性传力介质两种类型的界面接触。采用罚函数法计算接触力,推导了Mindlin轴对称壳单元和实体单元两种不同单元类型之间接触摩擦的有限元列式。采用静力显式... 详细信息

板材软模成形是板材和柔性传力介质耦合变形过程,存在板材和刚性模具及板材和柔性传力介质两种类型的界面接触。采用罚函数法计算接触力,推导了Mindlin轴对称壳单元和实体单元两种不同单元类型之间接触摩擦的有限元列式。采用静力显式的时间积分方法,通过控制载荷步长保持接触状态稳定。粘弹塑性软模材料的板材变形数值算例表明该算法是有效的。该算法也适用于其他类型软模材料的板材变形接触摩擦问题的处理。

关键词：板材软模成形有限元法接触摩擦静力显式

Microstructure-Property Relationship in Self-Crosslinked Non-Derivative Acetic Acid Lignin-Containing Polyurethane Membranes

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Green and Sustainable Chemistry 2014年第3期4卷 162-174页

作者： Baojian liu zhongjin Li Haihua wang Shaanxi University of Science & Technology Xi’an China

With the assistance of different solvents, self-crosslinked acetic acid lignin-containing polyurethane (LPU) membranes were synthesized. Compared with tetrahydrofuran and dioxane, N, N-dimethylacetamide with stronger polarity together with higher boiling point was demonstrated to be beneficial for preparing LPU particles of smaller size and enhanced binding force. It was also found that lignin domain can interpenetrate into polyurethane domain well with 43.3% lignin addition, resulting in enhanced phase mixing and better performance. In addition, relative homogeneous and smooth LPU membrane can be obtained with 2% TMP addition, while stress crack took place when TMP content was greater than 3%.

关键词： Polyurethane Phase Behavior Acetic Acid Lignin Membrane Microstructure

板材粘性介质压力成形粘性附着力影响因素试验研究

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机械工程学报 2006年第10期42卷 146-150页

作者：刘建光王忠金高铁军哈尔滨工业大学材料科学与工程学院哈尔滨150001

针对粘性介质压力成形过程是粘性介质与板材耦合的变形过程,不易确定板材在粘着应力作用下变形行为的情况,自行设计了粘性附着力拉伸试验装置,将粘着应力作为板材拉伸力,直接测量粘着应力对板材变形的作用。采用聚甲基乙烯基聚合物作为... 详细信息

针对粘性介质压力成形过程是粘性介质与板材耦合的变形过程,不易确定板材在粘着应力作用下变形行为的情况,自行设计了粘性附着力拉伸试验装置,将粘着应力作为板材拉伸力,直接测量粘着应力对板材变形的作用。采用聚甲基乙烯基聚合物作为成形传力介质,初步研究了粘性附着力拉伸过程板材受到的粘性介质粘性附着力对板材变形的影响以及粘性附着力的影响因素。试验结果表明,增大板材表面压力差、提高粘性介质流动速度及提高粘性介质压力有利于提高粘性附着力的作用。研究结果可为合理利用粘性附着应力作用,提高板材成形性提供理论基础。

关键词：粘性介质压力成形粘性附着力耦合变形