检索结果-南通市图书馆

Observation of ballistic-diffusive thermal transport in GaN transistors using thermoreflectance thermal imaging

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第1期43卷 389-394页

作者： Zhi-Ke Liu yang Shen Han-Ling Li bing-yang cao Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China

To develop effective thermal management strategies for gallium-nitride (GaN) transistors, it is essential to accurately predict the device junction temperature. Since the width of the heat generation in the devices is comparable to phonon mean free paths (MFPs) of GaN, phonon ballistic transport exists and can significantly affect the heat transport process.

关键词： temperature. transistors GaN

Study on Non-Newtonian Behaviors of Lennard-Jones Fluids via Molecular Dynamics Simulations

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Chemical Physics 2016年第6期29卷 754-760,I0002页

作者： Ruo-yu Dong bing-yang cao He-ming Yun Bao-ming Chen KeyLaboratoryofRenewableEnergyUtilizationTechnologiesinBuildingofMinistryofEducation ShandongJianzhuUniversityJinan250101China KeyLaboratoryforThermalScienceandPowerEngineeringofMinistryofEducation DepartmentofEngineeringMechanicsTsinghuaUniversityBeijing100084China

Using nonequilibrium molecular dynamics simulations, we study the non-Newtonian rhe-ological behaviors of a monoatomic fluid governed by the Lennard-Jones potential. Both steady Couette and oscillatory shear flows are investigated. Shear thinning and normal stress effects are observed in the steady Couette flow simulations. The radial distribution function is calculated at different shear rates to exhibit the change of the microscopic struc- ture of molecules due to shear. We observe that for a larger shear rate the repulsion between molecules is more powerful while the attraction is weaker, and the above phenomena can also be confirmed by the analyses of the potential energy. By applying an oscillatory shear to the system, several findings are worth mentioning here： First, the phase difference between the shear stress and shear rate increases with the frequency. Second, the real part of complex viscosity first increases and then decreases while the imaginary part tends to increase mono- tonically, which results in the increase of the proportion of the imaginary part to the real part with the increasing frequency. Third, the ratio of the elastic modulus to the viscous modulus also increases with the frequency. These phenomena all indicate the appearance of viscoelasticity and the domination of elasticity over viscosity at high oscillation frequency for Lennard-Jones fluids.

关键词： Non-Newtonian Viscoelasticity Lennard-Jones fluids Molecular dynamics

Extended social force model with a dynamic navigation field for bidirectional pedestrian flow

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Frontiers of physics 2017年第5期12卷 181-189页

作者： Yan-Qun Jiang Bo-Kui Chen bing-Hong Wang Weng-Fai Wong bing-yang cao School of Science Southwest University of Science and Technology Mianyang 621000 China School of Computing National University of Singapore Singapore 117417 Singapore Department of Modern Physics and Nonlinear Science Center University of Science and Technology of China Hefei 230026 China Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering Mechanics Tsinghua University Beijing 100084 China

An extended social force model with a dynamic navigation field is proposed to study bidirectional pedestrian movement. The dynamic navigation field is introduced to describe the desired direction of pedestrian motion resulting from the decision-making processes of pedestrians. The macroscopic fundamental diagrams obtained using the extended model are validated against camera-based observations. Numerical results show that this extended model can reproduce collective phenomena in pedestrian traffic, such as dynamic multilane flow and stable separate-lane flow. Pedestrians＇ path choice behavior significantly affects the probability of congestion and the number of self-organized lanes.

关键词： bidirectional pedestrian flow social force model dynamic navigation field collective phenomena complex systems

N-acetylcysteine blocked hypoxia-reoxygenation induced apoptosis through ROS-p38 MAPK signaling pathway in neonatal rat cardiomyocytes

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Geriatric Cardiology 2009年第3期6卷 168-172页

作者： Feng-Xiang Zhang Ming-Long Chen bing yang Ke-Jiang cao Cardiovascular Medical Center of Jiangsu the First Affiliated Hospital of Nanjing Medical University Nanjing China

Objective Previous investigations have shown that N-acetylcysteine （NAC） could regulate diverse cell type＇s apoptosis. The purpose of this study was to evaluate the mechanism of NAC reversed apoptosis of cardiomyocytes induced by hypoxia-reoxygenation （H/R）. Methods Cardiomyocytes were treated with hypoxia 6 h and reoxygenation 72 h in the absence and presence of NAC （100/2mol/ L）. The ROS was assayed by using Image-iTTM LIVE green reactive oxygen species detection kit. The viability of cell was assayed with trypan blue. Early stages ofapoptosis were assessed by flow cytometry using Annexin V, and late stages of apoptosis were assessed using TUNEL system. Bcl2 and bax mRNA levels were determined by real-time quantitative PCR. Bcl2, bax, p38 and pp38 protein levels were determined by western blot. Results We found that H/R could markedly increase ROS generation and induce the apoptosis of cardiomyocytes （P〈0.01）. NAC （10012 mol/L） significantly reduced the generation of ROS and apoptosis （P all 〈0.01）. NAC also significantly reduced the protein ratio of pp38 and p38 and increased the RNA and protein ratio of bcl2 and bax （P all 〈0.01）. Conclusion The results showed that NAC significantly reduced apoptosis through inhibiting the phosphorylation of p38 signal pathway, which has potential value for clinical cardiac diseases （J Geriatr Cardio12009; 6：168-172）.

关键词： NAC apoptosis hypoxia-reoxygenation ROS p38

Infrared Dual Spectral Imaging System

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Infrared Dual Spectral Imaging System

An Experimental Study on Flow Patterns and Width Adjustment in Self-formed Channels

2007亚洲光电子会议红外技术与应用分会场

作者： Wang Hai-tao,Geng An-bing,yang Chang-cheng,cao Qiong,Guo Liang-xian Huazhong Institute of Electro-Optics,Wuhan 430073,China

Based on the spectral characteristics of the target,dual spectral imaging system is conducted in target *** dual spectral system has simultaneously less false alarm probability and widened operating distance,There are many models of dual spectral system,such as ultraviolet and visible light,visible light and near infrared,mid-IR and long-IR system and *** principle of dual spectral system is described,and especially the paper studied deeply hybrid refractive-reflective dual-band system;refractive mid-IR and long-IR system.A designed sample of part-optics-light-path refractive detection system based on the application of re-imaging and 100% cold shield efficiency is given which is operating in the 3.7～4.8μm and 7.7～10.3μm wavelength bands and the rectification of the ray aberrations in both bands has been simultaneously *** of the same aperture、field of view and focal length,the dual spectral optical images can be coupled and be simultaneously displayed in one picture.

关键词： dual spectral,optical design,mid-IR,long-IR

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

四川大学学报(工程科学版) 2005年第S1期37卷 106-111页

作者： LFU Xingnian yang Kejun cao Shuyou SHI bing State Key Lab.of Hydraulics and Mountain River Eng. Sichuan Univ.Chengdu 610065China School of Civil Eng. Ocean Univ.of ChinaQingdao 266071China

The distribution of velocity is one of the basic issues in river *** on the experimental data measured by ADV in the flume of State Key Hydraulics Laboratory (SKHL),this paper analyzed the ver- tical distribution of point velocity and the varying law of turbulence intensity in straight mobile compound chan- nel with an asymmetric *** certain relative height,the streamwise point velocity follows the loga- rithmic *** the location,the velocity varies linearly approxim...

关键词： compound channels velocity turbulence intensity width adjustment mobile bed

Vectorial Bed load Equations and River Width Dynamic Adjustment Modeling

在线全文

学校读者我要写书评

暂无评论

四川大学学报（工程科学版） 2005年第S1期37卷 124-127页

作者： Shi, bing cao, Shuyou Liu, Xingnian yang, Kejun Lab. of Hydraulics and Mountain River Eng. Sichuan Univ. Chengdu 610065 China School of Eng. Ocean Univ. of China Qingdao 266071 China

Based on the analysis of forces acting on non-cohesive sediment particle under non-equilibrium con- dition,a vectorial equation of coarse particle movement on arbitrarily riverbed and the mathematical model used to simulate river width adjust are developed,some flume experiments for the time evolution of straight river channel are done.

关键词： sediment transport vectorial equation river width adjustment

Phonon relaxation and heat conduction in one-dimensional Fermi Pasta Ulam β lattices by molecular dynamics simulations

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2012年第1期21卷 279-283页

作者： Hou Quan-Wen cao bing-yang Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing 100084China Key Laboratory of Space Applied Physics and Chemistry of Ministry of Education Department of Applied PhysicsNorthwestern Polytechnical UniversityXi’an 710072China

The phonon relaxation and heat conduction in one-dimensional Fermi Pasta-Ulam （FPU） β lattices are studied by using molecular dynamics simulations. The phonon relaxation rate, which dominates the length dependence of the FPU β lattice, is first calculated from the energy autoeorrelation function for different modes at various temperatures through equilibrium molecular dynamics simulations. We find that the relaxation rate as a function of wave number k is proportional to k^1.688, which leads to a N^0.41 divergence of the thermal conductivity in the framework of Green-Kubo relation. This is also in good agreement with the data obtained by non-equilibrium molecular dynamics simulations which estimate the length dependence exponent of the thermal conductivity as 0.415. Our results confirm the N^2/5 divergence in one-dimensional FPU β lattices. The effects of the heat flux on the thermal conductivity are also studied by imposing different temperature differences on the two ends of the lattices. We find that the thermal conductivity is insensitive to the heat flux under our simulation conditions. It implies that the linear response theory is applicable towards the heat conduction in one-dimensional FPU β lattices.

关键词： thermal conductivity phonon relaxation low-dimensional heat conduction FermiPasta Ulam (FPU) Key Laboratory of Space Applied Physics and Chemistry of Ministry of Education Department of Applied Physics Northwestern Polytechnical University Xi'an 710072 China lattice

Mitophagy in acute central nervous system injuries:regulatory mechanisms and therapeutic potentials

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第9期20卷 2437-2453页

作者： Siyi Xu Junqiu Jia Rui Mao Xiang cao Yun Xu Department of Neurology Nanjing Drum Tower HospitalClinical College of Jiangsu UniversityNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalChinese Academy of Medical Science&Peking Union Medical CollegeNanjingJiangsu ProvinceChina Department of Neurology Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing UniversityNanjingJiangsu ProvinceChina State Key Laboratory of Pharmaceutical Biotechnology and Institute of Translational Medicine for Brain Critical Diseases Nanjing UniversityNanjingJiangsu ProvinceChina Jiangsu Key Laboratory for Molecular Medicine Medical School of Nanjing UniversityNanjingJiangsu ProvinceChina Nanjing Neurology Medical Center NanjingJiangsu ProvinceChina

Acute central nervous system injuries,including ischemic stro ke,intracerebral hemorrhage,subarachnoid hemorrhage,traumatic brain injury,and spinal co rd injury,are a major global health *** optimal therapies and improving the long-term neurological functions of patients with acute central nervous system injuries are urgent *** are susceptible to damage after acute central nervous system injury,and this leads to the release of toxic levels of reactive oxygen species,which induce cell ***,a selective form of autophagy,is crucial in eliminating redundant or damaged mitochondria during these *** evidence has highlighted the significant role of mitophagy in acute central nervous system *** this review,we provide a comprehensive overview of the process,classification,and related mechanisms of *** also highlight the recent developments in research into the role of mitophagy in various acute central nervous system injuries and drug therapies that regulate *** the final section of this review,we emphasize the potential for treating these disorders by focusing on mitophagy and suggest future research paths in this area.

关键词： autophagy intracerebral hemorrhage ischemic stroke mitochondria mitochondrial biogenesis mitochondrial quality control mitophagy spinal cord injury subarachnoid hemorrhage traumatic brain injury