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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第5期10卷 391-394页

作者： Yuan YUAN Fei LI Yue-min wang Rong-qing ZHANG Li-ping WEI hai-chang wang Department of Cardiology Xijing Hospital the Fourth Military Medical University Xi 'an 710032 China Department of Physiology the Fourth Military Medical University Xi 'an 710032 China

To shorten operation time and improve survival rate of rats with myocardial ischemia or myocardial infarction,we use a novel device comprised of a face mask and a head/neck retainer in this *** report the basic design of the novel respiratory face mask(RFM) and evaluate its performance in a rat model of myocardial *** device is cost-effective and easier to handle than other devices,such as tracheal *** with conventional tracheal intubation,we found that RFM shortens operation time significantly while keeping blood indices normal;the mean operation time for rats in the mask group was(32±3) min,and that for the intubation group was(45±7) min(Pchanged according to the body weight of *** conclusion,RFM is an appropriate device for the establishment of myocardial infarction or ischemia-reperfusion in rats.

关键词： Rats Respiratory face mask (RFM) Myocardial ischemia Myocardial infarction

Effect of Antibiotic Treatment on Toxin Production by Alexandrium tamarense

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Biomedical and Environmental Sciences 2003年第4期16卷 340-347页

作者： chang-hai wang, YI-YUN wang, YING-YING SUN, AND XIAN-TANG XIEDepartment of Bioengineering, Dalian University of Technology, Dalian 116024, Liaoning, China Department of Bioengineering Dalian University of Technology Dalian 116024 Liaoning Chin

Objective Impact of the presence of bacteria associated with a marine dinoflagellate, Alexandrium tamarense CI01, on the growth and toxin production of the algae in batch culture was investigated. Methods Pronounced changes in the activities of the algal culture were observed when the culture was treated with different doses of a mixture of penicillin and streptomycin. Results In the presence of antibiotics at the initial concentration of 100 u/mL in culture medium, both algal growth and toxin yield increased markedly. When the concentration of antibiotics was increased to 500 u/mL, the microalgal growth was inhibited, but resumed in a few days to eventually reach the same level of growth and toxin production as at the lower dose of the antibiotics. When the antibiotics were present at a concentration of 1 000 u/mL, the algal growth was inhibited permanently. Conclusions The results indicate that antibiotics can enhance algal growth and toxin production not only through their inhibition of the growth and hence competition for nutrients, but also through their effects on the physiology of the algae.

关键词： Alexandrium tamarense Harmful algal bloom Antibiotic Toxin Saxitoxin

Omnidirectional simulation analysis of thermomechanical coupling mechanism in inertia friction welding of Ni-based superalloy

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Chinese Journal of Aeronautics 2025年第1期38卷 202-216页

作者： chang-an LI Guoliang QIN Hao wang School of Materials Science and Engineering Shandong UniversityJinan 250061China

The coupling between heat and pressure is the kernel of inertia friction welding(IFW)and is still not fully understood.A novel 3D fully coupled finite element model based on a plastic friction pair was developed to simulate the IFW process of a Ni-based superalloy and reveal the omnidirectional thermo-mechanical coupling mechanism of the friction *** numerical model successfully simulated the deceleration,deformation processes,and peak torsional moments in IFW and captured the evolution of temperature,contact pressure,and *** simulated results were validated through measured thermal history,optical macrography,and axial *** results indicated that interfacial friction heat was the primary heat source,and plastic deformation energy only accounted for 4%of the *** increase in initial rotational speed and friction pressure elevated the peak temperature,reaching a maximum of 1525.5K at an initial rotational speed of 2000 r/min and friction pressure of 400 *** interface heat generation could form an axial temperature gradient exceeding 320K/*** radial inhomogeneities of heat generation and temperature were manifested in a concentric ring distribution with maximum heat flux and temperature ranging from 2/5 to 2/3 *** radial inhomogeneities were caused by increasing linear velocity along the radius and an opposite distribution of contact pressure,which could reach 1.7 times the set pressure at the *** circumferential inhomogeneity of thermomechanical distribution during rotary friction welding was revealed for the first time,benefiting from the 3D *** deflection and transformation of distribution in contact pressure and Mises stress were indicators of plastic deformation and transition of quasi-steady state *** critical Mises stress was 0.5 times the friction pressure in this *** presented modeling provides a reliable insight into the thermo-mechanical coupling mechanism of IFW and lays a solid found

关键词： Inertia friction welding Thermo-mechanical coupling Inhomogeneity Numerical simulation Ni-based superalloy

Bifurcations and Spatiotemporal Patterns in the Diffusive Nutrient-Microor ganism Model

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Acta Mathematicae Applicatae Sinica 2025年第1期41卷 162-178页

作者： Ya-di wang hai-long YUAN Yan-ling LI School of Arts and Sciences Shaanxi University of Science and TechnologyXi'an 710021China School of Mathematics and Statistics Xi'an Jiaotong UniversityXi'an 710049China School of Mathematics and Information Science Shaanxi Normal UniversityXi'an 710062China

In this paper,the diffusive nutrient-microorganism model subject to Neumann boundary conditions is *** Hopf bifurcations and steady state bifurcations which bifurcate from the positive constant equilibrium of the system are investigated in *** addition,the formulae to determine the direction of Hopf and steady state bifurcations are *** results show the existence of spatially homogeneous/nonhomogeneous periodic orbits and steady state solutions,which indicates the spatiotemporal dynamics of the *** numerical simulations are also presented to support the analytical results.

关键词： nutrient-microorganism model Hopf bifurcation steady state bifurcation simulations

Influence of minor cerium addition on microstructure and fluidity of as-cast Al-Cu-Mn-Mg alloy

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Journal of Rare Earths 2025年第2期43卷 377-383页

作者： Yishan wang Yu Bai Kaixi Jiang Wenxue Fan Puxuan wang hai Hao Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province) School of Materials Science and EngineeringDalian University of Technology Ningbo Research Institute of Dalian University of Technology

Al-Cu-Mn alloys are widely used to produce automobile components like cylinder heads and engine blocks because of their capability to retain excellent thermal and mechanical characteristics at high ***,the Al-Cu-Mn-based alloys demonstrate restricted fluidity,leading to casting defects such as shrinkage and incomplete *** research investigated the microstructure and fluidity of Al-4.7Cu-1.0Mn-0.5Mg（wt%） alloy with minor cerium（Ce） *** as-cast alloys predominantly comprise α-Al matrix,accompanied by the presence of Al2Cu,Al6Mn,and Al8Cu4Ce *** influence of adding Ce on the fluidity of the Al-4.7Cu-1.0Mn-0.5Mg alloy was investigated using a trispiral fluidity test mold in this *** findings suggest that the addition of Ce within the range of 0.1 wt% to 0.5 wt% in the Al-4.7Cu-1.0Mn-0.5Mg alloy results in an enhancement in ***,the alloy containing 0.4 wt% Ce exhibits a significant increase in fluidity distance,from 349.7 to 485.7 *** improvement can be attributed to the reduction in viscosity,the refinement of secondary dendrite arm spacing,and the modification of secondary phase ***,a higher concentration of Ce leads to a decrease in fluidity length,potentially due to the formation of Al8Cu4Ce.

关键词： Al-Cu-Mn-Mg alloy Ce addition Fluidity Microstructure Rare earths

Potential dependence in electrocatalysis:a theoretical perspective

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Science China Chemistry 2025年第1期68卷 21-25页

作者： Leyu Liu Zhaoming Xia Zeyu wang Yinjuan Chen hai Xiao Department of Chemistry Tsinghua UniversityBeijing 100084China Fundamental Science Center of Rare Earths Ganjiang Innovation AcademyChinese Academy of SciencesGanzhou 341119China Key Laboratory of Advanced Catalytic Materials and Technology Advanced Catalysis and Green Manufacturing Collaborative Innovation CenterChangzhou UniversityChangzhou 213164China

Electrocatalysis is a key technology for the new energy era and sustainable development,serving as the interface for interconversion of electrical and chemical energies,which spans a wide spectrum of applications in sustainable energy and environmental *** reactions including electrochemical CO_(2)reduction reaction(eCO_(2)RR),hydrogen evolution reaction(HER),and oxygen evolution/reduction reactions(OER/ORR),hold essential promise for renewable energy technologies as well as complement the biogeochemical carbon and oxygen cycles.

关键词： spectrum interface Electrocatalysis

Do Institutional Investor Cliques Undermine Stock Price Efficiency?

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China & World Economy 2025年第1期33卷 223-258页

作者： hai Jiang Shuangyi Chen Zifeng wang School of Economics Jinan UniversityChina Dongguan Academy of Social Sciences China

This study investigates the effects of institutional investor cliques on stock price efficiency. Using a community network algorithm, it identifies cliques of institutional investors and finds that they significantly undermined stock price efficiency in China. The robustness of this finding is demonstrated through a range of methodologies, including the substitution of dependent variables, the alteration of estimation methods, the exclusion of data from extreme market periods, and the application of instrumental variables. The role of institutional investor cliques in diminishing market efficiency is attributed to market speculation. The detrimental effect of cliques on efficiency is exacerbated in environments characterized by low stock liquidity, poor information disclosure, and heightened panic among retail investors. However, regulatory interventions, such as inquiry letters, are shown to mitigate these effects and enhance market efficiency. These findings highlight the unexpected ways institutional investor cliques can influence emerging market economies and underscore the critical importance of effective regulation to safeguard market efficiency.

关键词： emerging market economics institutional investor clique stock pric efficiency

Release characteristics of arsenic from sediments and its source or sink competition with phosphorus:A case of a great lake with grass-algae alternation

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Journal of Environmental Sciences 2025年第3期149卷 278-287页

作者： Shuhang wang Yongsheng chang Wei Huang Dianhai Yang Feifei Che State Key Laboratory of Pollution Control and Resource Reuse College of Environmental Science and EngineeringTongji UniversityShanghai 200092China College of Environmental Science and Engineering Donghua UniversityShanghai 201620China National Engineering Laboratory for Lake Pollution Control and Ecological Restoration Chinese Research Academy of Environmental SciencesBeijing 100012China

The arsenic(As)release from sediments in great lakes is affected by various *** this study,the characteristics of As release fromsediments was investigated,and the As sources and sinks with the strengths in sediments from different areas(grass-type,algae-type,and grass-algae alternation areas)in great shallow lakes(Taihu Lake,China)were analyzed,and the influence of P competition in the process of As release was also *** results showed that changing trend of the values of equilibrium As concentration in sediments were consistent with the regional changes(0 to 28.12μg/L),and the sediments from algaetype areas had the higher *** sediments from western lake and northwest lake bay were a strong As and a weak P source,and the north lake bay had the opposite trend of these two *** P source competition with As from the sediments occurred in algae-type *** grass-type areas had strong As and P retention capacities,indicating a sink role of sediment with high As and P sorption *** degree of As and P saturation had similar trend in sediments,and the grass-type areas had the higher values,18.3%-21.4%and 15.31%-20.34%,*** analysis results showed that most of As release contribution was from the bottom(30-50 cm)sediments,and the surface(0-10 cm)sediments from algae-type areas contributed more to the overlying water than other region.

关键词： Arsenic Phosphorus Sediment Source and sink Contribution

Controlling segregation and hardenability of gear steel based on as-cast structure

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Journal of Iron and Steel Research International 2025年第1期32卷 144-158页

作者： hai-jie wang Ze Zhang Peng Lan Gang Chen Pu wang Chuan-hui Jiang Jia-quan Zhang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Weifang Iron and Steel Group Co. Ltd.Weifang 261000ShandongChina

Hardenability significantly impacts the distortion of gear during heat treatment,correlated to the uniformity of solute distribution in steel *** experimental analysis was conducted on the macrostructure,solute distribution,dendrite structure,and rod hardenability of 20CrMnTiH gear steel in continuously cast blooms and hot roller *** evaluation approach by the standards for the hardenability of gear steel rods and the corresponding blooms was analyzed,and the inheritance mechanism from solidification segregation to hardenability fluctuation of gear steel was *** results indicate that semi-macroscopic spot segregation located in the equiaxed zone exhibits larger size,higher solute enrichment,and worse solute homogeneity,leading to significant solute fluctuations in the blooms and hardenability fluctuation in the *** increasing the liquid steel superheat from 35 to 40℃,reducing the mold electromagnetic stirring from 300 to 100 A,and implementing the soft reduction(SR)of 7 mm at the solidification end,the equiaxed ratio of the strand decreased from 26.42%to 6.69%.Consequently,the solute fluctuation range and standard deviation decrease significantly in the transverse section,while the maximum segregation ratio,average fluctuation range,and average standard deviation of solutes C,Cr,and Mn in the spot segregation decrease at the same *** the meanwhile,the equiaxed ratio of the rod decreased from 24.89%to 4.09%,and the structure of the hardenability detection zone was transformed from equiaxed crystals to columnar ***,the solute fluctuation range and standard deviation in the transverse section decreased,while the homogeneity in spot segregation was also *** hardness difference of A and B surfaces at J9 and J15 positions was smaller than 2 HRC,meeting the qualification standard for hardenability.

关键词： Gear steel Continuous casting Solute distribution Dendritic structure Hardenability

等通道角变形对搅拌铸造SiC_P/AZ91复合材料显微组织与室温性能的影响

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复合材料学报 2017年第3期34卷 611-618页

作者：常海王金龙郑明毅王晓军北京科技大学材料服役安全科学中心北京100083 哈尔滨工业大学材料科学与工程学院哈尔滨150001

采用搅拌铸造法成功制备了SiC_P/Mg(AZ91)复合材料并对铸态复合材料进行了等通道角挤压变形(Equal channel angular pressing,ECAP)。结果表明,搅拌铸造态SiC_P/AZ91复合材料的基体组织致密,颗粒与基体结合良好,没有出现宏观团聚;SiC_P... 详细信息

采用搅拌铸造法成功制备了SiC_P/Mg(AZ91)复合材料并对铸态复合材料进行了等通道角挤压变形(Equal channel angular pressing,ECAP)。结果表明,搅拌铸造态SiC_P/AZ91复合材料的基体组织致密,颗粒与基体结合良好,没有出现宏观团聚;SiC_P大部分聚集在晶界附近区域并呈"项链状"分布。ECAP变形可以有效地消除铸态SiC_P/AZ91复合材料中的SiC_P"项链状"分布,并且随着ECAP道次的增加,SiC_P分布更加均匀;在ECAP过程中,SiC_P发生了一定断裂但并不明显。SiC_P/AZ91复合材料基体晶粒随着变形道次的提高而逐渐细化。基体晶粒细化以及SiC_P分布均匀化是SiC_P/AZ91复合材料屈服强度和抗拉强度随着道次提升而逐渐增加的主要原因。

关键词：搅拌铸造等通道角挤压变形 SiCP/AZ91 金属基复合材料显微组织室温性能