检索结果-南通市图书馆

BOUNDARY PENALTY FINITE ELEMENT METHODS FOR BLENDING SURFACES,I BASIC THEORY

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 1998年第5期16卷 457-480页

作者： zi-cai li (Department of Applied Mathematics, National Sun Yat-sen University,Kaohsiung 80242, Taiwan) National Sun Yat-sen Univerisy 台湾

When parametric functions are used to blend 3D surfaces, geometric continuity of displacements and derivatives until to the surface boundary must be satisfied. By the traditional blending techniques, however, arbitrariness of the solutions arises to cause a difficulty in choosing a suitable blending surface. Hence to explore new blending techniques is necessary to construct good surfaces so as to satisfy engineering requirements. In this paper, a blending surface is described as a flexibly elastic plate both in partial differential equations and in their variational equations, thus to lead to a unique solution in a sense of the minimal global surface curvature. Boundary penalty finite element methods (BP-FEMs) with and without approximate integration are proposed to handle the complicated constraints along the blending boundary. Not only have the optimal convergence rate O(h(2)) of second order generalized derivatives of the solutions in the solution domain been obtained, but also the high convergence rate O(h(4)) of the tangent boundary condition of the solutions can be achieved, where h is the maximal boundary length of rectangular elements used. Moreover, useful guidance in computation is discovered to deal with interpolation and approximation in the boundary penalty integrals. A numerical example is also provided to verify perfectly the main theoretical analysis made. This paper yields a framework of mathematical modelling, numerical techniques and error analysis to the general and complicated blending problems.

关键词： blending surfaces parametric surfaces plate mathematical modelling variational equations finite element methods boundary penalty method computer geometric aided design

Micro segment analysis of supercritical methane thermal-hydraulic performance and pseudo-boiling in a PCHE straight channel

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2024年第2期21卷 1275-1289页

作者： Qian li zi-Jie lin liu Yang Yue Wang Yue li Wei-Hua cai Laboratory of Thermo-Fluid Science and Nuclear Engineering Northeast Electric Power UniversityJilin132000JilinChina School of Energy and Power Engineering Northeast Electric Power UniversityJilin132000JilinChina

The printed circuit heat exchanger(PCHE) is receiving wide attention as a new kind of compact heat exchanger and is considered as a promising vaporizer in the LNG process. In this paper, a PCHE straight channel in the length of 500 mm is established, with a semicircular cross section in a diameter of 1.2 *** simulation is employed to investigate the flow and heat transfer performance of supercritical methane in the channel. The pseudo-boiling theory is adopted and the liquid-like, two-phase-like, and vapor-like regimes are divided for supercritical methane to analyze the heat transfer and flow *** results are presented in micro segment to show the local convective heat transfer coefficient and pressure drop. It shows that the convective heat transfer coefficient in segments along the channel has a significant peak feature near the pseudo-critical point and a heat transfer deterioration when the average fluid temperature in the segment is higher than the pseudo-critical point. The reason is explained with the generation of vapor-like film near the channel wall that the peak feature related to a nucleateboiling-like state and heat transfer deterioration related to a film-boiling-like state. The effects of parameters, including mass flow rate, pressure, and wall heat flux on flow and heat transfer were *** calculating of the averaged heat transfer coefficient of the whole channel, the traditional method shows significant deviation and the micro segment weighted average method is adopted. The pressure drop can mainly be affected by the mass flux and pressure and little affected by the wall heat flux. The peak of the convective heat transfer coefficient can only form at high mass flux, low wall heat flux, and near critical pressure, in which condition the nucleate-boiling-like state is easier to appear. Moreover,heat transfer deterioration will always appear, since the supercritical flow will finally develop into a filmboiling-like state. So hea

关键词： Printed circuit heat exchanger Vaporization Supercritical methane Pseudo-boiling Micro segment analysis

lithium-induced graphene layer containing li_(3)P alloy phase to achieve ultra-stable electrode interface for lithium metal anode

在线全文

学校读者我要写书评

暂无评论

Rare Metals 2024年第2期43卷 562-574页

作者： Jia-Xin Chen Guo-Qiang Zhang Xian-Ying Qin Kui lin zi-Jin Yang Ge-Meng liang Yue Xia Guo-Bin Zhang Hai-Kun Wu Qiu-Chan cai Hai lin Bao-Hua li Shenzhen Key Laboratory on Power Battery Safety Research and Shenzhen Geim Graphene Center Tsinghua Shenzhen International Graduate SchoolShenzhen518055China Shenzhen Graphene Innovation Center Co. Ltd.Shenzhen518107China School of Chemical Engineering and Advanced Materials The University of AdelaideAdelaideSA5005Australia Department of Chemistry City University of Hong KongHong Kong990077China

Uncontrolled growth of lithium dendrite will lead to low Coulombic efficiency and poor cycle stability,which hinders the commercialization of lithium metal ***,a novel modified lithium anode with reduced graphene oxide conductive network containing trace lithiophilic phosphorus(P-rGO/Cu)is prepared by electrospraying technique combined with heat treatment *** rGO layer has a concave and undulating conductive structure,which can significantly improve the effective electrical contact between lithium metal and the current collector,speed up the kinetics of interfacial electron transport and reaction,and improve the resistance of the negative electrode to the internal stress caused by volume change of the lithium,which is advantageous for the stability of the SEI *** extremely small and uniformly distributed red phosphorus element avoids the volume change caused by lithiation to the maximum *** two-phase compound li_(3)P obtained by alloying P with li can directionally induce the homogeneous nucleation and dense deposition of lithium metal,address the issue of lithium dendrites and extend the cycle life of the *** obtained P-rGO/Cu exhibits excellent electrochemical performance with an average Coulombic efficiency(CE)of 98%at a current density of 1 mA·cm^(−2) for 400 cycles,and the capacity retention rate of the full cell matched with lithium iron phosphate(LFP)is 83%after 400 cycles at 1C.

关键词： lithium anode Dendrite-free lithiophilicity Induced nucleation deposition

Adaptive Stabilization and Trajectory Tracking of Airship with Neutral Buoyancy

在线全文

学校读者我要写书评

暂无评论

自动化学报 2008年第11期34卷 1437-1440页

作者： ZHANG Yan QU Wei-Dong XI Yu-Geng cai zi-li Department of Automation Shanghai Jiao Tong University Shanghai 200240 P. R. China Research and Development Center GE （China） Co. Ltd. Shanghai 201203 P. R. China

这份报纸介绍一个适应非线性的控制答案给一架自治飞艇的水平运动。我们定义包括配置错误和速度错误的错误功能的一个新奇家庭。然后，我们建立错误系统。稳定错误系统的适应非线性的控制器被 Lyapunov 直接方法和 Matrosov 定理设计。... 详细信息

这份报纸介绍一个适应非线性的控制答案给一架自治飞艇的水平运动。我们定义包括配置错误和速度错误的错误功能的一个新奇家庭。然后，我们建立错误系统。稳定错误系统的适应非线性的控制器被 Lyapunov 直接方法和 Matrosov 定理设计。数字研究被介绍说明建议控制器的有效性。

关键词：自适应系统稳定性轨迹飞船浮力

New insights into the pre-lithiation kinetics of single-crystalline Ni-rich cathodes for long-life li-ion batteries

在线全文

学校读者我要写书评

暂无评论

Green Energy & Environment 2024年第3期9卷 556-564页

作者： Qiang Han Lele cai Zhaofeng Yang Yanjie Hu Hao Jiang Chunzhong li Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Chemical EngineeringEast China University of Science and TechnologyShanghai200237China Key Laboratory for Ultrafine Materials of Ministry of Education School of Materials Science and EngineeringEast China University of Science and TechnologyShanghai200237China

Developing single-crystalline Ni-rich cathodes is an effective strategy to improve the safety and cycle life of li-ion batteries(liBs).However,the easy-to-loss of li and O in high-temperature lithiation results in unsatisfactory ordered layered structure and ***,we demonstrate the synthesis of highly-ordered and fully-stoichiometric single-crystalline liNi_(0.83)Co_(0.12)Mn_(0.05)O_(2)(SC-NCM83)cathodes by the regulation of pre-lithiation *** well-balanced pre-lithiation kinetics have been proved to greatly improve the proportion of layered phase in the intermediate by inhibiting the formation of metastable spinel phase,which promoted the rapid transformation of the intermediate into highly-ordered layered SC-NCM83 in the subsequent lithiation *** coating a layer of li_(2)O–B_(2)O_(3),the resultant cathodes deliver superior cycling stability with 90.9%capacity retention at 1C after 300 cycles in pouch-type full *** enhancement mechanism has also been *** findings exhibit fundamental insights into the pre-lithiation kinetics process for guiding the synthesis of high-quality singlecrystalline Ni-rich cathodes.

关键词： Single-crystalline cathode Ni-rich oxides Pre-lithiation li-ion batteries Surface modification

Combined effects of ultrasonic vibration and FeCoNiCrCu coating on interfacial microstructure and mechanical properties of Al/Mg bimetal by compound casting

在线全文

学校读者我要写书评

暂无评论

China Foundry 2024年第5期21卷 588-598页

作者： Yuan-cai Xu Wen-ming Jiang Qing-qing li ling-hui Yu Xiao-peng Yu zi-tian Fan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

In this work,a new treatment method combining ultrasonic vibration with FeCoNiCrCu high entropy alloy(HEA)coating was used to prepared Al/Mg bimetal through the lost foam compound *** effects of composite treatment involving ultrasonic vibration and HEA coating on interfacial microstructure and mechanical properties of Al/Mg bimetal were *** demonstrate that the interface thickness of the Al/Mg bimetal with composite treatment significantly decreases to only 26.99%of the thickness observed in the untreated Al/Mg *** HEA coating hinders the diffusion between Al and Mg,resulting the significant reduction in Al/Mg intermetallic compounds in the *** Al/Mg bimetal interface with composite treatment is composed of Al_(3)Mg_(2)and Mg_(2)Si/AlxFeCoNiCrCu+FeCoNiCrCu/δ-Mg+Al_(12)Mg_(17)eutectic *** interface resulting from the composite treatment has a lower hardness than that without *** acoustic cavitation and acoustic streaming effects generated by ultrasonic vibration promote the diffusion of Al elements within the HEA coating,resulting in a significant improvement in the metallurgical bonding quality on the Mg *** fracture position shifts from the Mg side of the Al/Mg bimetal only with HEA coating to the Al side with composite *** shear strength of the Al/Mg bimetal increases from 32.16 MPa without treatment to 63.44 MPa with ultrasonic vibration and HEA coating,increasing by 97.26%.

关键词： ultrasonic vibration FeCoNiCrCu HEA coating Al/Mg bimetal interfacial microstructure shear strength compound casting

Catalytic anode surface enabling in situ polymerization of gel polymer electrolyte for stable li metal batteries

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

Nano Research 2024年第6期17卷 5216-5223页

作者： Guocheng li Kang liang Yuanjian li Xiangrui Duan lin Fu Zhao cai Zhaofu Zhang Jiangnan Dai Yongming Sun Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China The Institute of Technological Sciences Wuhan UniversityWuhan 430074China Faculty of Materials Science and Chemistry China University of Geoscience(Wuhan)Wuhan 430074China

Employing quasi-solid-state gel polymer electrolyte(GPE)instead of the liquid counterpart has been regarded as a promising strategy for improving the electrochemical performance of li metal ***,the poor and uneven interfacial contact between li metal anode and GPE could cause large interfacial resistance and electrochemical li stripping/plating inhomogeneity,deteriorating the electrochemical ***,we proposed that the functional component of composite anode could work as the catalyst to promote the in situ polymerization reaction,and we experimentally realized the integration of polymerized-dioxolane electrolyte and li/li_(22)Sn_(5)/liF composite electrode with low interfacial resistance and good stability by in situ catalyzation ***,the reaction kinetics and stability of metallic li anode were significantly *** a demonstration,symmetric cell using such a GPE-li/li_(22)Sn_(5)/liF integration achieved stable cycling beyond 250 cycles with small potential hysteresis of 25 mV at 1 mA·cm^(−2)and 1 mAh·cm^(−2),far outperforming the counterpart regular GPE on pure *** with liNi0.5Co0.3Mn0.2O2,the full cell with the GPE-li/li_(22)Sn_(5)/liF integration maintained 85.7%of the original capacity after 100 cycles at 0.5 C(1 C=200 mA·g^(−1)).Our research provides a promising strategy for reducing the resistance between GPE and li metal anode,and realizes li metal batteries with enhance electrochemical performance.

关键词： catalyzation polymerization interface resistance interfacial stability li metal batteries electrochemical performance

Insights into the interplay between gut microbiota and lipid metabolism in the obesity management of canines and felines

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 Animal Science and Biotechnology 2024年第5期15卷 1761-1777页

作者： Kaiqi li Xiangyu Xiao Yuling li Sichen Lu Jianghang zi Xiaoqiang Sun Jia Xu Hao‑Yu liu Xiaoqiong li Tongxing Song Demin cai Laboratory of Animal Physiology and Molecular Nutrition Jiangsu Key Laboratory of Animal Genetic Breeding and Molecular DesignCollege of Animal Science and TechnologyYangzhou UniversityYangzhou 225009China College of Animal Science and Technology Huazhong Agricultural UniversityWuhan 430070China School of life Science and Engineering Foshan UniversityFoshan 528231China State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro‑Products Institute of Food ScienceZhejiang Academy of Agricultural SciencesHangzhouZhejiang 310021People’s Republic of China College of Agriculture Jinhua PolytechnicJinhua 321017China

Obesity is a prevalent chronic disease that has significant negative impacts on humans and our companion animals,including dogs and *** occurs with multiple comorbidities,such as diabetes,hypertension,heart disease and osteoarthritis in dogs and cats.A direct link between lipid metabolism dysregulation and obesity-associated diseases has been ***,the understanding of such pathophysiology in companion animals is *** review aims to address the role of lipid metabolism in various metabolic disorders associated with obesity,emphasizing the involvement of the gut ***,we also discuss the management of obesity,including approaches like nutritional interventions,thus providing novel insights into obesity prevention and treatment for canines and felines.

关键词： Cat Dog Gut microbiota lipid metabolism Obesity Management

Semi-supervised remote sensing image scene classification with prototype-based consistency

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第2期37卷 459-470页

作者： Yang li Zhang li zi WANG Kun WANG Qifeng YU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Deep learning significantly improves the accuracy of remote sensing image scene classification,benefiting from the large-scale ***,annotating the remote sensing images is time-consuming and even tough for *** neural networks trained using a few labeled samples usually generalize less to new unseen *** this paper,we propose a semi-supervised approach for remote sensing image scene classification based on the prototype-based consistency,by exploring massive unlabeled *** this end,we,first,propose a feature enhancement module to extract discriminative *** is achieved by focusing the model on the foreground ***,the prototype-based classifier is introduced to the framework,which is used to acquire consistent feature *** conduct a series of experiments on NWPU-RESISC45 and Aerial Image Dataset(AID).Our method improves the State-Of-The-Art(SOTA)method on NWPU-RESISC45 from 92.03%to 93.08%and on AID from 94.25%to 95.24%in terms of accuracy.

关键词： Semi-supervised learning Remote sensing Scene classification Prototype network Deep learning