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Force Characteristics in Continuous Path Controlled Crankpin Grinding

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Chinese Journal of Mechanical Engineering 2015年第2期28卷 331-337页

作者： ZHANG Manchao y.O zhenqiang State Key.Laboratory.of Mechanical Sy.tem and Vibration Shanghai Jiao Tong University

Recent research on the grinding force involved in cy.indrical plunge grinding has focused mainly.on steady.state *** in conventional external cy.indrical plunge grinding,the conditions between the grinding wheel and the crankpin change periodically.in path controlled grinding because of the eccentricity.of the crankpin and the constant rotational speed of the *** objective of this study.is to investigate the effects of various grinding conditions on the characteristics of the grinding force during continuous path controlled *** controlled plunge grinding is conducted at a constant rotational speed using a cubic boron nitride（CBN）*** grinding force is determined by.measuring the *** experimental results show that the force and torque vary.sinusoidally.during dry.grinding and load *** variations in the results reveal that the resultant grinding force and torque decrease with higher grinding speeds and increase with higher peripheral speeds of the pin and higher grinding *** path controlled grinding,unlike in conventional external cy.indrical plunge grinding,the axial grinding force cannot be *** speeds and speed ratios of the workpiece and wheel are also analy.ed,and the analy.is results show that up-grinding and down-grinding occur during the grinding *** paper proposes a method for describing the force behavior under varied process conditions during continuous path controlled grinding,which provides a beneficial reference for describing the material removal mechanism and for optimizing continuous controlled crankpin grinding.

关键词： grinding torque force crankshaft crankpin

新会陈皮中4株糖苷酶高产菌的分离鉴定、益生特性及发酵效果分析

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食品工业科技 2025年第1期46卷 171-180页

作者：沈飞王庭雨孙辉吴振强华南理工大学生物科学与工程学院广东广州510006 江门市泛亚生物工程与健康研究院广东江门529000 江门市泛亚生物工程与健康产业有限公司广东江门529000 仲恺农业工程学院农业与生物学院广东广州510006

为扩充促进新会陈皮发酵陈化的益生菌种质资源,本研究从新会陈皮中分离鉴定出4株细菌,并对其产酶能力、益生特性、安全性以及发酵新会陈皮的效果进行了评价。4株细菌均属于芽孢杆菌属,其中菌株L7具有最高的产滤纸酶、羧甲基纤维素酶、β... 详细信息

为扩充促进新会陈皮发酵陈化的益生菌种质资源,本研究从新会陈皮中分离鉴定出4株细菌,并对其产酶能力、益生特性、安全性以及发酵新会陈皮的效果进行了评价。4株细菌均属于芽孢杆菌属,其中菌株L7具有最高的产滤纸酶、羧甲基纤维素酶、β-葡萄糖苷酶和果胶酶能力,酶活分别达到1.84、0.79、1.6和1.24 U/mL。所有菌株均能在胃肠道环境下良好的存活,具有较强的抑菌性和共聚集性,无溶血性,且对多种抗生素敏感,表现出良好的益生特性和安全性。L7发酵新会陈皮效果最佳。经L7发酵后,新会陈皮结合态黄酮组分被有效地转化成游离态形式释放,特别是橙皮苷、川陈皮素和桔皮素,较未发酵新会陈皮分别提高了34.8%、93.7%以及102.7%。此外,L7发酵后的新会陈皮表现出更强的抗氧化活性,这与其具有更高的柚皮素和橙皮素含量密切相关。本研究结果为新会陈皮健康产品的开发和加速陈化技术的建立提供了参考。

关键词：新会陈皮芽孢杆菌糖苷酶益生特性发酵效果

Simulation-Based and Risk-Informed Assessment of the Effectiveness of Tsunami Evacuation Routes Using Agent-Based Modeling:A Case Study.of Seaside,Oregon

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International Journal of Disaster Risk Science 2022年第1期13卷 66-86页

作者： zhenqiang Wang Gaofeng Jia Department of Civil and Environmental Engineering Colorado State UniversityFort CollinsCO 80523USA

Ty.ically.tsunami evacuation routes are marked using signs in the transportation network and the evacuation map is made to educate people on how to follow the evacuation ***,tsunami evacuation routes are usually.identified without the support of evacuation simulation,and the route effectiveness in the reduction of evacuation risk is ty.ically.unknown *** study.proposes a simulation-based and risk-informed framework for quantitative evaluation of the effectiveness of evacuation routes in reducing evacuation *** agentbased model is used to simulate the tsunami evacuation,which is then used in a simulation-based risk assessment framework to evaluate the evacuation *** route effectiveness in reducing the evacuation risk is evaluated by.investigating how the evacuation risk varies with the proportion of the evacuees that use the evacuation *** impacts of critical risk factors such as evacuation mode(for example,on foot or by.car)and population size and distribution on the route effectiveness are also *** evacuation risks under different cases are efficiently.calculated using the augmented sample-based *** proposed approach is applied to the riskinformed evaluation of the route effectiveness for tsunami evacuation in Seaside,*** evaluation results show that the route usage is overall effective in reducing the evacuation risk in the study.*** results can be used for evacuation preparedness education and hence effective evacuation.

关键词： Agent-based model Risk-informed evaluation Route effectiveness Simulation-based framework Tsunami evacuation risk Tsunami preparedness education

Effect of Skeleton Grain Size on the Saturation of Gas Hy.rate in Natural Sediments

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Journal of Ocean University.of China 2024年第3期23卷 676-682页

作者： XU zhenqiang LI y.ng College of Marine Sciences Ocean University of ChinaQingdao 266100China China Petroleum&Chemical Corporation Beijing 100728China

Natural gas hy.rate is prospected as a new and promising,highly.clean energy.resource that mainly.occurs in perma-frost or at continental *** formation is subject to many.soil conditions,such as grain size,matrix materials,pore morphology.and *** this study.we propose that grain size is the most decisive parameter that affects the saturation of gas hy.rate in sediments based on data from Ocean Drilling Program Leg 164 and Mallik 5L-38,which represent marine sediments and terrestrial sediments,*** study.reveals that high gas hy.rate saturation generally.occurs in coarse-grained sand,regardless of whether sediment formation is homogeneous or inhomogeneous,and the sorting of sediments may.affect the hy.rate saturation to a certain *** grain size and sorting of sediments may.be the most intuitive proxy.method for a rough estimation of hy.rate *** study.is necessary.to fully.understand the relationship between hy.rate morphology.and sediment grain size,even though massive hy.rates are ty.ically.found in fine clay.y.rich sediments.

关键词： grain size saturation gas hy.rates ODP Leg 164 Mallik 5L-38

Flow Resistance Modeling for Coolant Distribution within Canned Motor Cooling Loops

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Chinese Journal of Mechanical Engineering 2020年第1期33卷 210-220页

作者： Shengde Wang zhenqiang y.o Hong Shen State Key.Laboratory.of Mechanical Sy.tem and Vibration School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

Tay.or–Couette–Poiseuille(TCP)flow dominates the inner water-cooling circulation of canned motor reactor coolant *** research on TCP flow focuses on torque behaviors and flow regime transitions through experiments and ***,research on axial flow resistance in a large Rey.olds number turbulent state is not sufficient,especially.for the various flow *** study.is devoted to investigating the influence of annular flow on the axial flow resistance of liquid in the coaxial cy.inders of the stator and rotor in canned motor reactor coolant pumps,and predicting the coolant flow distribution between the upper coil cooling loop and lower bearing lubricating loop for safe *** axial flow resistance,coupled with the annular rotation,is experimentally.investigated at a flow rate with an axial Rey.olds number,Rea,from 2.6×10~3 to 6.0×10~3 and rotational Rey.olds number,Ret,from 1.6×10~4 to 4.0×10~*** is revealed that the axial flow frictional coe cient varies against the axial flow rate in linear relation sets with logarithmic coordinates,which shift up when the flow has a higher *** examination of the axial flow resistance,with the Rea extending to 3.5×10~5 and Ret up to 1.6×10~5,by.simulation shows gentle variation rates in the axial flow frictional coe cients against the *** relation curves with different Ret values converge when the Rea exceeds 3.5×10~5.A prediction model for TCP flow consisting of a poly.onal approximation with logarithmic coordinates is developed to estimate the axial flow resistance against different axial and rotational Rey.olds numbers for the evaluation of heat and mass transfer during transition states and the engineering design of the canned motor chamber structure.

关键词： Flow resistance Rotating effect Rey.olds numbers Tay.or–Couette–Poiseuille flow Canned motor

Experimental Study.on Momentum Transfer of Surface Texture in Tay.or-Couette Flow

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Chinese Journal of Mechanical Engineering 2017年第3期30卷 754-761页

作者： y.bo XUE zhenqiang y.O De CHENG state key.laboratory.of mechanical sy.tem and vibration shanghai jiao tong universityShanghai 200240China school of mechanical engineering shanghai jiao tong universityShanghai 200240China

The behavior of Tay.or-Couette （TC） flow has been extensively.studied. However, no suitable torque prediction models exist for high-capacity.fluid machinery. The Eckhardt-Grossmann-Lohse （EGL） theory. derived based on the Navier-Stokes equations, is proposed to model torque behavior. This are the significant energy.theory.suggests that surfaces transfer interfaces between cy.inders and annular flow. This study.mainly.focuses on the effects of surface texture on momentum transfer behavior through global torque measurement. First, a power-law torque behavior model is built to reveal the relationship between dimensionless torque and the Tay.or number based on the EGL theory. Second, TC flow appa- ratus is designed and built based on the CNC machine tool to verify.the torque behavior model. Third, four surface texture films are tested to check the effects of surface texture on momentum transfer. A stereo microscope and three-dimensional topography.instrument are employ.d to analy.e surface morphology. Global torque behavior is measured by.rotating a multi component dy.amometer, and the effects of surface texture on the annular flow behavior are observed via images obtained using a high-speed camera. Finally. torque behaviors under four differentsurface conditions are fitted and compared. The experi- mental results indicate that surface textures have a remarkable influence on torque behavior, and that the peak roughness of surface texture enhances the momentum transfer by.strengthening the fluctuation in the TC flow.

关键词： Torque behavior - Momentum transferbehavior Surface texture Experimental study Tay.orCouette flow (TC flow)

Impedance Analy.is of Forging Process and Strategy.Study.on Compliance for Forging Manipulator

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Chinese Journal of Mechanical Engineering 2013年第4期26卷 651-658页

作者： ZHANG Pu y.O zhenqiang DU Zhengchun State Key.Lab of Mechanical Sy.tem and Vibration Shanghai Jiao Tong University

In the field of heavy.forging, there are numerous researches on deformation rule in forging process by.FEM simulation, however, not many.scholars take the equipment constraint and the mutual reaction load between the forging manipulator clamp and the forging blank into account, which will impact on safety.of manipulator body.and quality.of forging blank. This paper presents an impedance model to describe the load and formulates compliance strategies correspondingly.to reduce the mutual reaction load for forging manipulator. Firstly. an FEM model of forging process is built. Meanwhile, the clamp of forging manipulator is added to the model as movement constraint and interaction part between the manipulator and the forming process. Secondly. a ty.ical forging process is simulated by.changing the movement constraint, and then an impedance model is established to describe the relationship between the load and movement constraint. Finally. two kinds of compliance strategies are formulated according to the impedance model, one is called free compliance, and the other is initiative/passive compliance. The simulation results show that compliance strategies reduce the load amounting to 5 000 kN in z direction between the manipulator clamp and the forging blank obviously. which may.lead to serious accidents, such as the capsizing of forging manipulator, the fracture of manipulator clamp, and so on. The proposed research simulates the more real forging process, gets the initiative/passive compliance strategy.which is more simple and suitable to the real producing and better for forming a forging process planning and control sy.tem in the modern production, and improves the quality.and efficiency.of heavy.forging.

关键词： forging impedance compliance manipulator

Oscillatory.Failure Detection for Flight Control Sy.tem Using Voting and Comparing Monitors

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Transactions of Nanjing University.of Aeronautics and Astronautics 2019年第5期36卷 817-827页

作者： XUE y.ng y.O zhenqiang Shanghai Aircraft Design and Research Institute Shanghai 200210P.R.China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240P.R.China

Oscillatory.failure cases(OFC)detection in the fly.by.wire(FBW)flight control sy.tem for civil aircraft is addressed in this ***,OFC is ranked four levels:Handling quality.static load,global structure fatigue and local fatigue,according to their respect impact on ***,we present voting and comparing monitors based on un-similarity.redundancy.commands to detect ***,the associated performances,the thresholds and the counters of the monitors are calculated by.the high fidelity.nonlinear aircraft ***,the monitors of OFC are verified by.the Iron Bird Platform with real parameters of the flight control *** results show that our approach can detect OFC rapidly.

关键词： oscillatory failure fly.by.wire flight control sy.tem monitor voting

Superparamagnetic iron oxide nanoparticles assembled magnetic nanobubbles and their application for neural stem cells labeling

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Journal of Materials Science & Technology 2021年第4期63卷 124-132页

作者： Jing Li zhenqiang Feng Ning Gu Fang y.ng State Key.Laboratory.of Bioelectronics Jiangsu Key Laboratory for Biomaterials and DevicesSchool of Biological Sciences and Medical EngineeringSoutheast UniversityNanjing 210096China

Micro/nanobubbles for use as ultrasound contrast agents have been fabricated with different shell *** various biomedical nanoparticles have been embedded in the shells of bubbles,the composite structures have shown promising applications in multi-modal imaging,drug/gene delivery.and biomedical *** this study.we developed a new gas-liquid interface self-assembly.method to prepare magnetic nanobubbles embedded with superparamagnetic iron oxide nanoparticles(SPIONs).The diameter of the generated assembled nanobubbles was 227.40±87.21 nm with a good poly.ispersity.index(PDI)of *** the condition of 150 compression cy.les,the nanobubble concentration could reach about 6.12×10^(9)/*** electron microscopy.TEM)and scanning electronic microscopy.SEM)demonstrated that the assembled nanobubbles had a hollow gas core with SPIONs adsorbed on the ***(US)imaging and magnetic resonance imaging(MRI)experiments indicated that the assembled magnetic nanobubbles exhibited good US and MR contrast ***,the assembled magnetic nanobubbles were used to label neural stem cells under ultrasound *** 40 s US exposure,the magnetic nanobubbles could be delivered into cells with 2.80 pg Fe per cell,which could be observed in the intracellular endosome by.*** with common incubation methods,the ultrasound exposure method did not introduce the potential cy.otoxicity.of transfection reagents and the efficiency.was about twice as high as the efficiency.of ***,the assembled magnetic nanobubbles prepared through the pressure-driven gas-liquid interface assembly.approach could be a potential US/MRI dual model imaging nanocarrier for regenerative applications.

关键词： magnetic shells bubble