检索结果-南通市图书馆

The Electronic Structure and Formation Energies of Ni-doped CuAlO2 by Density Functional Theory Calculation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics Letters 2014年第3期31卷 118-121页

作者： XU Ying LI Fei SHENG Wei NIE Guo-Zheng yuan ding-wang School of Physics Hunan University of Science and Technology Xiangtan 411202 Department of Education Science Hunan First Normal University Changsha 410205 College of Materials Science and Engineering Hunan University Changsha 410082

The electronic structure and formation energies of Ni-doped CuAlO2 are calculated by first-principles calculations. Our results show that Ni is good for p-type doping in CuAlO2. When Ni is doped into CuAlO2, it prefers to substitute Al-site. NiAl is a shallow acceptor, while NiCu is a deep acceptor and its formation energy is high. Further electronic structure calculations show that strong hybridization happens between Ni-3d and O-2p states for Ni substituting Al-site, while localized Ni-3d states are found for Ni substituting Cu-site.

关键词： SEMICONDUCTOR doping RESEARCH DENSITY functional theory FERMI energy ELECTRONIC structure -- Research PHYSICS research

Analytical Expression for the Atomic Friction of a Single Asperity Based on the Prandtl-Tomlinson Model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2024年第3期37卷 416-422页

作者： Weike yuan Yue ding Gangfeng wang Xinrui Niu Department of Engineering Mechanics SVLMMLXi’an Jiaotong UniversityXi’an710049China Department of Mechanical Engineering City University of Hong KongHong Kong SAR999077China

The Prandtl-Tomlinson(PT)model has been widely applied to interpret the atomic friction mechanism of a single *** this study,we present an approximate explicit expression for the friction force in the one-dimensional PT model under quasi-static ***‘stick-slip’friction curves are first approximated properly by sawtooth-like lines,where the critical points before and after the‘slip’motion are described analytically in terms of a dimensionless parameterη.Following this,the average friction force is expressed in a closed form that remains continuous and valid forη>***,an analytical expression for the load dependence of atomic friction of a single asperity is derived by connecting the parameterηwith the normal *** the parameters reported in experiments,our prediction shows good agreement with relevant experimental results.

关键词： Atomic friction Stick-slip friction Prandtl-Tomlinson model Friction force microscope

Data-driven discovery of linear dynamical systems from noisy data

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Science China(Technological Sciences) 2024年第1期67卷 121-129页

作者： wang YaSen yuan Ye FANG HuaZhen ding Han School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China State Key Lab of Digital Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Artificial Intelligence and Automation Huazhong University of Science and TechnologyWuhan 430074China Department of Mechanical Engineering University of KansasLawrence 66045USA

In modern science and engineering disciplines,data-driven discovery methods play a fundamental role in system modeling,as data serve as the external representations of the intrinsic mechanisms within ***,empirical data contaminated by process and measurement noise remain a significant obstacle for this type of *** this study,we have developed a data-driven method capable of directly uncovering linear dynamical systems from noisy *** method combines the Kalman smoothing and sparse Bayesian learning to decouple process and measurement noise under the expectation-maximization framework,presenting an analytical method for alternate state estimation and system ***,the discovered model explicitly characterizes the probability distribution of process and measurement noise,as they are essential for filtering,smoothing,and stochastic *** have successfully applied the proposed algorithm to several simulation *** results demonstrate its potential to enable linear dynamical system discovery in practical applications where noise-free data are intractable to capture.

关键词： system identification sparse Bayesian learning Kalman smoothing process and measurement noise

Delaying Modified QUICK Scheme and its Application in Slug Flow

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2001年第2期10卷 139-143页

作者： LU yuan-Wei HE An-ding wang Yue-She ZHOU Fang-De The National Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong University Xi’an China

The National Laboratory of Multiphase Flow in Power Engineering Xi' an Jiaotong University, Xi' an 710049, China Abstract:Calculations of several classic questions in numerical heat transfer with delaying modified QUICK scheme show good agreement with benchrnark. Combining volume of fluid model with the well known SIMPLEC method. the reasonanble Tgylor bubble shape has ben obtained by using delaying modified QUICK scheme and donor acceptor scheme of interfacial advection respectively. At the same the the stream field and the liquid film thickness around the Taylor bubble have been well figured out

关键词： slug flow Taylor-bubbles QUICK scheme SIMPLEC method.

Development of CONTHAC-3D and hydrogen distribution analysis of HPR1000

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2024年第2期35卷 210-221页

作者： Hui wang Jing-Jing Li yuan Chang Gong-Lin Li Ming ding China Nuclear Power Engineering Co.LTD. Beijing 100084China Fundamental Science on Nuclear Safety and Simulation Technology Laboratory Harbin 100049China

An in-house code,CONTHAC-3D,was developed to calculate and analyze thermal-hydraulic phenomena in containments during severe ***-3D is a three-dimensional computational fluid dynamics code that can be applied to predict gas flow,diffusion,and steam condensation in a containment during a severe hypothetical accident,as well as to obtain an estimate of the local hydrogen concentration in various zones of the ***-3D was developed using multiple models to simulate the features of the proprietary systems and equipment of HPR1000 and ACP100,such as the passive cooling system,passive autocatalytic recombiners and the passive air cooling *** validate CONTHAC-3D,a GX6 test was performed at the Battelle Model Containment *** hydrogen concentration and temperature monitored by the GX6 test are accurately predicted by ***,the hydrogen distribution in the HPR1000 containment during a severe accident was *** results show that the hydrogen removal rates calculated using CONTHAC-3D for different types of PARs agree well with the theoretical values,with an error of less than 1%.As the accident progresses,the hydrogen concentration in the lower compartment becomes higher than that in the large space,which implies that the lower compartment has a higher hydrogen risk than the dome and large space at a later stage of the *** amount of hydrogen removed by the PARs placed on the floor of the compartment is small;therefore,raising the installation height of these recombiners appropriately is ***,we do not recommend installing all autocatalytic recombiners at high *** study findings in regard to the hydrogen distribution in the HPR1000 containment indicate that CONTHAC-3D can be applied to the study of hydrogen risk containment.

关键词： Hydrogen risk mitigation Pressurized water reactor HPR1000 Thermal hydraulic CONTHAC-3D

Heat management technology for solid-state high voltage and high repetitive pulse generators:Towards better effects and reliability

在线全文

学校读者我要写书评

暂无评论

High Voltage 2024年第1期9卷 2-21页

作者： Yanan wang Linyuan Ren Zihao Yang Saikang Shen Zichen Deng Qi yuan Weidong ding Zhenjie ding School of Electrical Engineering Xi'an Jiaotong UniversityXi'anChina School of Electronic and Information Engineering Xi'an Jiaotong UniversityXi'anChina

Solid-state high voltage high repetitive pulse generators have a broad prospect in various *** high power and high-frequency operation of the pulse generator suffer from the massive heat dissipation problem,which limits the improvement of the output parameters and even affects the *** article focuses on heat management technology for high voltage high repetitive pulse ***,the typical circuit topology of the high repetitive pulse generators was *** the perspective of different application requirements,the demands of the heat management design were ***,the heat generation characteristics and difficulties of solid-state high voltage high repetitive pulse generators were ***,the different stateof-art cooling techniques were reviewed,and their applicability and limitations for the high voltage high repetitive generators were ***,a flow chart for heat management design was given.

关键词： pulse state high

Dual-curvilinear beam enabled tunable manipulation of high-and low-refractive-index particles

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Photonics Research 2024年第7期12卷 1427-1436页

作者： ZHENG yuan CHENCHEN ZHANG yuan GAO WENXIANG YAN XIAN LONG ZHI-CHENG REN XI-LIN wang JIANPING ding HUI-TIAN wang National Laboratory of Solid State Microstructures and School of Physics Nanjing UniversityNanjing 210093China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093China Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics Nanjing 210093China

We present an innovative approach for the simultaneous agile manipulation of high-refractive-index(HRI) and low-refractive-index(LRI) particles. Our method involves introducing a dual-curvilinear optical vortex beam(DC-OVB) generated by superimposing a pair of curved beams: HRI and LRI particles are controlled by the bright curve and the dark channel between the two curves, respectively. The proposed DC-OVB provides customizable motion paths and velocities for both LRI and HRI particles. Each curve of the DC-OVB can support a distinct orbital flow density(OFD), enabling the application of torques to HRI and LRI particles, guiding them to orbit along specified trajectories and prompting them to execute various curvilinear motions simultaneously,including curvilinear movement, revolution, and rotation.

关键词： tunable refractive beam

Dynamic Response of A Group of Cylindrical Storage Tanks with Baffles Considering the Effect of Soil Foundation

在线全文

学校读者我要写书评

暂无评论

China Ocean Engineering 2024年第1期38卷 129-143页

作者： SUN Ying wang Jia-dong HUO Rui-li ZHOU ding GU Zhen-yuan QIAN wang-ping School of Transportation and Civil Engineering Nantong UniversityNantong 226019China Faculty of Civil Engineering and Mechanics Jiangsu UniversityZhenjiang 212013China College of Civil Engineering Nanjing Tech UniversityNanjing 211816China

The sloshing in a group of rigid cylindrical tanks with baffles and on soil foundation under horizontal excitation is studied *** solutions for the velocity potential are derived out by the liquid subdomain *** models with mass-spring oscillators are established to replace continuous *** with the least square technique,Chebyshev polynomials are employed to fit horizontal,rocking and horizontal-rocking coupling impedances of soil,respectively.A lumped parameter model for impedance is presented to describe the effects of soil on tank structures.A mechanical model for the soil-foundation-tank-liquid-baffle system with small amount of calculation and high accuracy is proposed using the substructure *** analytical solutions are in comparison with data from reported literature and numerical codes to validate the effectiveness and correctness of the *** dynamic properties and seismic responses of the soil-tank system are given for the baffle number,size and location as well as soil parameter.

关键词： cylindrical tanks multiple annular baffles equivalent analytical model soil−structure interaction subdomain method dynamic response

Iso-propagation vortices with OAM-independent size and divergence toward future faster optical communications

在线全文

学校读者我要写书评

暂无评论

Advanced Photonics 2024年第3期6卷 51-59页

作者： Wenxiang Yan Zhaozhong Chen Xian Long yuan Gao Zheng yuan Zhi-Cheng Ren Xi-Lin wang Jianping ding Hui-Tian wang Nanjing University School of Physics National Laboratory of Solid State Microstructures Nanjing University Collaborative Innovation Center of Advanced Microstructures University of Glasgow James Watt School of Engineering Nanjing University Collaborative Innovation Center of Solid-State Lighting and Energy-Saving Electronics

Recognized in the 1990s, vortex beams' ability to carry orbital angular momentum(OAM) has significantly contributed to applications in optical manipulation and high-dimensional classical and quantum information communication. However, inherent diffraction in free space results in the inevitable expansion of beam size and divergence contingent upon the OAM, limiting vortex beams' applicability in areas such as spatial mode multiplexing communication, fiber-optic data transmission, and particle manipulation. These domains necessitate vortex beams with OAM-independent propagation *** introduce iso-propagation vortices(IPVs), vortex beams characterized by OAM-independent propagation behavior, achieved through precise radial index configuration of Laguerre–Gaussian beams. IPVs display notable transmission dynamics, including a reduced quality factor, resilience post-damage, and decreased and uniform modal scattering under atmospheric turbulence. Their distinctive attributes render IPVs valuable for potential applications in imaging, microscopy, optical communication, metrology, quantum information processing, and light–matter interactions. Notably, within optical communication, the case study suggests that the IPV basis, due to its OAM-independent propagation behavior, provides access to a more extensive spectrum of data channels compared with conventional spatial multiplexing techniques, consequently augmenting information capacity.

关键词： orbital angular momentum optical communication structured light optical vortices