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Acta Metallurgica Sinica(English Letters) 2010年第1期23卷 41-49页

作者： Fang wang Weicheng cui China Ship Scientific Research Center Wuxi 214082 China

A new model for the analysis of fatigue crack growth in the metal structures was proposed. This model shows a promising capability of explaining various fatigue phenomena. The new crack growth model is further completed by a continuous empirical formula for estimating the value of variable fracture toughness during crack propagation and a modified continuous equation for the crack tip stress/strain constraint factor used to calculate the stress intensity factor at the opening level. The prediction results are proved to agree well with the observed phenomena in test.

关键词： Marine structures Crack growth rate Three dimensional stress state Fracture toughness Crack tip stress/strain constraint factor

Hybrid multiple attribute decision making model based on entropy

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Journal of Systems Engineering and Electronics 2007年第1期18卷 72-75页

作者： wang Wei cui Mingming Dept. of Management Science Naval Univ. of Engineering Wuhan 430033 P.R. China

From the viewpoint of entropy, this paper investigates a hybrid multiple attribute decision making problem with precision number, interval number and fuzzy number. It defines a new concept： project entropy and the de... 详细信息

关键词： Decision making Project entropy Hybrid multiple attribute Fuzzy number

Simulation Study on Hydrogen-Heating-Power Poly-Generation System based on Solar Driven Supercritical Water Biomass Gasification with Compressed Gas Products as an Energy Storage System

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Journal of Thermal Science 2020年第2期29卷 365-377页

作者： JIN Hui wang cui FAN Chao State Key Laboratory of Multiphase Flow in Power Engineering Xi'an Jiaotong UniversityXi'an 710049China

Supercritical water gasification driven by solar energy is a promising way for clean utilization of biomass with high moisture content, but direct discharge of liquid residual causes energy waste and decreases energy efficiency. To reduce energy waste, a poly-generation system for hydrogen-rich gas production coupling heat supply and power generation based on supercritical water gasification of biomass driven by concentrated solar energy was established in this paper, which also provided a novel energy storage method to overcome the shortcomings of solar discontinuity. Thermodynamic model of the system was proposed and life cycle assessment(LCA) of the system was conducted. Influence of different parameters(temperature of 600℃ to 800℃, outlet temperature of heat exchanger of 42℃ to 56℃, biomass slurry concentration of 5% to 6.5%) on the gasification performance, energy and exergy efficiency, energy distribution and global warming potential(GWP) was discussed. The results indicated that hydrogen yield increased as gasification temperature increased since free radical reaction was enhanced which gas production reaction was classified into. Molar fraction of hydrogen increased as gasification temperature increased and reached 65.6% at 750℃. Energy and exergy efficiency of the system reached 74.84% and 34.87% at 700℃ and 600℃ respectively and that of gas production was 18.15% at 650℃, which was the highest. Increasing reaction temperature and decreasing biomass slurry concentration were effective ways to decrease GWP. Optimal operating parameter was reaction temperature of 650℃, outlet temperature of heat exchanger of 50℃ and biomass concentration of 5%.

关键词： biomass supercritical water gasification poly-generation system thermodynamics analysis energy storage life cycle assessment

Stable Lagrangian numerical differentiation with the highest order of approximation

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Science China Mathematics 2006年第2期49卷 225-232页

作者： wang Xinghua cui Feng Department of Mathematics Zhejiang University Hangzhou 310028 China Department of Mathematics Zhejiang University Hangzhou 310028 China

Some asymptotic representations for the truncation error for the Lagrangian numerical differentiation are presented, when the ratio of the distance between each interpolation node and the differentiated point to step-parameter h is known. Furthermore, if the sampled values of the function at these interpolation nodes have perturbations which are bounded by ε, a method for determining step-parameter h by means of perturbation bound ε and order n of interpolation is provided to saturate the order of approximation. And all the investigations in this paper can be generalized to the set of quasi-uniform nodes.

关键词： Lagrangian numerical differentiation truncation error stability saturation approximation superconvergence

Enantioselective induction of oxidative stress by acetofenate in rat PC12 cells

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Journal of Environmental Sciences 2010年第12期22卷 1980-1986页

作者： Ling Li Fen Hu cui wang Xuedong wang Research Center of Environmental Science College of Biological and Environmental Engineering Zhejiang University of Technology Hangzhou 310032 China School of Environmental Science and Public Health Wenzhou Medical College Wenzhou 325035 China

In a non-chiral environment, the enantiomers of a racemate possessed the identical physico-cbemical properties, but in the biological systems they possessed different activities. Considering that the involvement of oxidative damage has been implicated in the toxicities of various pesticides, this study investigated the possibility of enantioselective oxidative stress and cytotoxicity induction by acetofenate （AF） which contains an asymmetrical center on PC12 cells. The results of the cytotoxicity assay indicated that S-（＋）-AF presented more toxic effects than R-（-）-AF and （＋）-AF. It also demonstrated that S-（＋）-AF possessed the strongest effects in induction of reactive oxygen species （ROS） production, decrease in superoxide dismutase （SOD） and catalase （CAT） activities, and increase in malondialdehyde （MDA） level. These results suggested that AF and its enanfiomers could induce enantioselecfive cytotoxicity in PC12 cells mediated by oxidative stress. Therefore, the assessment in environmental safety and new chiral pesticide development should consider enantioselectivity.

关键词： chiral organochlorine pesticides acetofenate enantioselectivity cytotoxicity oxidative stress

Effect of V and V-N Microalloying on Deformation-Induced Ferrite Transformation in Low Carbon Steels

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Journal of Materials Science & Technology 2006年第2期22卷 159-163页

作者： Kai wang Lijun wang Wenfang cui Chunming LIU School of Materials and Metallurgy Northeastern University Shenyang 110004 China

Deformation-induced ferrite transformation （DIFT） has been proved to be an effective approach to refine ferrite grains. This paper shows that the ferrite grains can further be refined through combination of DIFT and V or V-N microalloying. Vanadium dissolved in γ matrix restrains DIFT. During deformation, vanadium carbonitrides rapidly precipitate due to strain-induced precipitation, which causes decrease in vanadium dissolved in matrix and indirectly accelerates DIFT. Under heavy deformation, deformation induced ferrite （DIF） grains in V microalloyed steel were finer than those in V free steel. The more V added to steel, the finer DIF grains obtained. Moreover, the addition of N to V microalloyed steels can remarkably accelerate precipitation of V, and then promote DIFT. However, DIF grains in V-N microalloyed steel easily coarsen.

关键词： Deformation induced ferrite transformation Strain induced precipitation V microalloyed steel V-N microalloyed steel Thermomechanical simulation

Semi-solid Thixoforming Simulation of Al-Cu-Mn-Ti Alloy Parts via AnyCasting

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Journal of Materials Science & Technology 2007年第3期23卷 359-362页

作者： Ping wang Jianzhong cui Guimin LU Key Laboratory of Ministry of Education for Electromagnetic Processing of Materials Northeastern University Shenyang 110004 China

The software AnyCasting was used to simulate the thixotropic die-casting process of semi-solid Al-Cu-Mn-Ti alloy slurry to form the parts of a particular shape, especially on how the in-gate size of die and injection speed affect the process. The results showed that the die cavity can be filled well with the semi-solid slurry in form of laminar flow under conditions that the temperature of the semi-solid slurry is 640℃ and that of die 200-240℃, thickness of in-gate is 11 mm and, more important, the injection speed should be changed from 0.1 to 1.0 m/s when 60% of die cavity has been filled. The simulation result is highly proved in conformity to the actual die-casting specimens in accordance to the filling process as simulated. Moreover, the hardness of the specimens is up to 116.6 HV after the treatment of solid solution plus underaging, i.e. 45.7% higher than that in conventional ones.

关键词： Al-Cu-Mn-Ti alloy Seml-solid die casting Laminar flow Hardness

Evolution of gp85 gene of subgroup J avian leukosis virus under the selective pressure of antibodies

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Science China(Life Sciences) 2006年第3期49卷 227-234页

作者： wang Zhengfu cui Zhizhong College of Animal Science and Veterinary Medicine Shandong Agricultural University Taian 271018 China College of Animal Science and Veterinary Medicine Shandong Agricultural University Taian 271018 China

Subgroup J Avian leucosis virus (ALV-J) strain NX0101 was inoculated into chicken embryo fibroblasts (CEF) monolayers in 6-well plates. The six wells of CEF inoculated with NX0101 were divided into groups A (without anti-ALV-J serum in the medium); B (with anti-ALV-J serum in the medium), then viruses from each well of both groups were separately passed in CEF every 6 d; formed their independent passage lineages. For each lineage of both groups, gp85 genes of the viruses in the 10th, 20th; 30th passages were amplified, cloned; sequenced. The sequence data indicated that the homologies of gp85 at aa level between the primary virus; the passed viruses of different passages of 3 lineages in group A were 97.7%–99.7%;; the homologies of gp85 between the primary virus; the passed viruses of different passages of 3 lineages in group B were 93.8%–96.1%. Analysis of the ratios of nonsynonium (NS) vs synonium (S) mutations of nucleic acids demonstrated that NS/S in 3 highly variable (hr-) regions at aa#110–120, aa#141–151; aa#189–194 of gp85 in 3 lineages of group A were 2 (8/4), 1(3/3); 1.3 (4/3), however, NS/S in the same 3 hr-regions of group B were 4.1 (13/3), 4.7 (14/3); 3.3 (11/3). This study is the first demonstration of influence of immune selective pressure on evolution of ALV-J gp85 by specific antibodies under the controlled in vitro experiments.

关键词： subgroup J avian leucosis virus, gp85 gene, evolution, immune selection.

Hydrodynamic constraints on the energy efficiency of droplet electricity generators

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Microsystems & Nanoengineering 2021年第3期7卷 209-218页

作者： Antoine Riaud cui wang Jia Zhou wanghuai Xu Zuankai wang State Key Laboratory of ASIC and System School of MicroelectronicsFudan UniversityShanghai200433China Department of Mechanical Engineering City University of Hong KongHong Kong999077China

Electric energy generation from falling droplets has seen a hundred-fold rise in efficiency over the past few ***,even these newest devices can only extract a small portion of the droplet *** this paper,we theoretically investigate the contributions of hydrodynamic and electric losses in limiting the efficiency of droplet electricity generators(DEG).We restrict our analysis to cases where the droplet contacts the electrode at maximum spread,which was observed to maximize the DEG ***,the electro-mechanical energy conversion occurs during the recoil that immediately follows droplet *** then identify three limits on existing droplet electric generators:(i)the impingement velocity is limited in order to maintain the droplet integrity;(ii)much of droplet mechanical energy is squandered in overcoming viscous shear force with the substrate;(iii)insufficient electrical charge of the *** all these effects,we found that up to 83%of the total energy available was lost by viscous dissipation during *** this loss by using cascaded DEG devices to reduce the droplet kinetic energy may increase future devices efficiency beyond 10%.

关键词： viscous constraints limiting

Dynamic Modeling and Analysis of 9-DOF Omnidirectional Legged Vehicle

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Chinese Journal of Mechanical Engineering 2011年第4期24卷 515-521页

作者： GAO Feng wang Guofu cui Ying YANG Xinhong School of Transportation Science ＆ Engineering Beihang University Beijing 100191 China

The omnidirectional legged vehicle with steering-rails has a specific mechanism feature, and it can be controlled flexibly and accurately in omnidirectional motion. Currently there lacks further research in this area. In this paper, the mechanical characteristics of independent walking control and steering control and its kinematics principle are introduced, and a vehicle has a composite motion mode of parallel link mechanism and steering mechanism is presented. The motion direction control of the proposed vehicle is only dependant on its steering rails, so its motion is simple and effective to control. When the relative motion between the walking and steering is controlled cooperatively, the vehicle can walk perfectly. By controlling the steering rails, the vehicle can walk along arbitrary trajectory on the ground. To achieve a good result of motion control, an equivalent manipulator model needs to be built. In terms of the mechanism feature and the kinematic principle, the simplified manipulator model consists of a rail in stance phase, a rail in swing phase, and an equivalent leg. Considering the ground surface slope during walking, a parameter of inclination angle is added. Based on such a RPP manipulator model, the equations of motion are derived by means of Lagrangian dynamic approach. To verify the dynamic equations, the motion of the manipulator model is simulated based on linear and nonlinear motion planning. With the same model and motion parameters, the dynamic equations can be solved by Matlab and the calculation data can be gained. Compared with the simulation data, the result confirms the manipulator dynamic equations are correct. As a result of such special characteristics of the legged mechanism with steering rails, it has a potential broad application prospects. The derivation of dynamics equation could benefit the motion control of the mechanism.

关键词： legged vehicle omnidirectional motion steering rails dynamic modeling dynamic simulation