检索结果-南通市图书馆

Molecular Dynamics Simulation of Behaviours of Non-Polar Droplets Merging and Interactions with Hydrophobic Surfaces

在线全文

学校读者我要写书评

暂无评论

Journal of Bionic Engineering 2008年第4期5卷 271-281页

作者： y.y. yan c.y. Ji School of the Built Environment University of Nottingham Nottingham NG7 2RD UK

This paper presents a molecular dynamics simulation of the behaviours of non-polar droplets merging and also the fluid molecules interacting with a hydrophobic surface. Such behaviours and transport phenomena are popular in general microchannel flow boiling and two-phase flow. The droplets are assumed to be composed of Lennards-Jones type molecules. Periodic boundary conditions are applied in three coordinate directions of a 3-D system, where there exist two liquid droplets and their vapour. The two droplets merge when they come within the prescribed small distance. The merging of two droplets apart from each other at different initial distances is tested and the possible larger （or critical） non-dimensional distance, in which droplets merging can occur, is discussed. The evolution of the merging process is simulated numerically by employing the Molecular Dynamics （MD） method. For interactions with hydrophobic solid wall, a system with fluid confined between two walls is used to study the wetting phenomena of fluid and solid wall. The results are compared with those of hydrophilic wall to show the unique characteristics of hydrophobic interactions by microscopic methods.

关键词： molecular dynamics simulation mist flow droplets merging hydrophobic wetting

cyclic stress-controlled tests on offshore clay

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2017年第2期9卷 376-381页

作者： S.y. Thian c.y. Lee Department of civil Engineering Jalan Ikram-UnitenUniversiti Tenaga NasionalKajang43000Malaysia

One of the main concerns in cyclic behavior of soft clay is gradual degradation with the progression of loading cycle.A series of cyclic constant-volume direct simple shear(cDSS) loading tests was performed on Malaysia offshore clay to study its undrained *** testing program consists of stresscontrolled tests with cyclic shear ratio ranging from 0.34 to 0.83 at different overconsolidation ratios(OcRs).For a given cyclic stress ratio in stress-controlled tests,the accumulated cyclic strain and pore water pressure increase with elevated number of *** heavily overconsolidated clay specimens,the negative cyclic pore water pressure is generated followed by positive cyclic pore water pressure as cyclic tests *** post-cyclic strength of offshore clay specimens is reduced by undrained cyclic stresscontrolled loading.

关键词： Offshore clay cyclic degradation Undrained cyclic loading Shear strength Pore pressure Overconsolidation ratio(OcR)

Miyaoka-type inequalities for terminal threefolds with nef anti-canonical divisors

在线全文

学校读者我要写书评

暂无评论

Science china Mathematics 2025年第1期68卷 1-18页

作者： Masataka Iwai chen Jiang Haidong Liu Department of Mathematics Graduate School of ScienceOsaka University Shanghai center for Mathematical Sciences & School of Mathematical Sciences Fudan University Department of mathematics Sun Yat-sen University

In this paper,we study Miyaoka-type inequalities on chern classes of terminal projective 3-folds with nef anti-canonical *** X be a terminal projective 3-fold such that-KXis *** show that if c1（X） · c2（X）≠0,then c1（X） · c2（X） ≥ 1/252;if further X is not rationally connected,then c1（X） · c2（X） ≥ 4/5 and this inequality is *** order to prove this,we give a partial classification of such varieties along with many *** also study the nonvanishing of c1（X）dim X-2· c2（X） for terminal weak Fano varieties and prove a Miyaoka-Kawamata-type inequality.

关键词： terminal threefolds Miyaoka-type inequality boundedness

PREDIcTION FOR FORMING LIMIT OF AL2024T3 SHEET BASED ON DAMAGE THEORy USING FINITE ELEMENT METHOD

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Mechanica Solida Sinica 2006年第2期19卷 174-180页

作者： Tang c.y. Fan Jianping Tsui c.P. Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong China School of civil Engineering and Mechanics Huazhong University of Science and Technology Wuhan 430074 China

This paper presents the application of anisotropic damage theory to the study of forming limit diagram of A12024T3 aluminum alloy sheet. In the prediction of limiting strains of the aluminum sheet structure, a finite element cell model has been constructed. The cell model consists of two phases, the aluminum alloy matrix and the intermetallic cluster. The material behavior of the aluminum alloy matrix is described with a fully coupled elasto-plastic damage constitutive equation. The intermetallic cluster is assumed to be elastic and brittle. By varying the stretching ratio, the limiting strains of the sheet under biaxial stretching have been predicted by using the necking criterion proposed. The prediction is in good agreement with the experimental findings. Moreover, the finite element cell model can provide information for understanding the microscopic damage mechanism of the aluminum alloy. Over-estimation of the limit strains may result if the effect of material damage is ignored in the sheet metal forming study.

关键词： forming limit diagram (FLD) anisotropic damage finite element method (FEM) limit strain localized necking elasto-plastic deformation

construction of 3D porous cu_(1.81)S/nitrogen-doped carbon frameworks for ultrafast and long-cycle life sodium-ion storage

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 191-200页

作者： chen chen Hongyu Xue Qilin Hu Mengfan Wang Pan Shang Ziyan Liu Tao Peng Deyang Zhang yongsong Luo Key Laboratory of Microelectronics and Energy of Henan Province Henan Joint International Research Laboratory of New Energy Storage TechnologyCollege of Physics and Electronic EngineeringXinyang Normal UniversityXinyang 464000China School of Physics and Electronic Engineering Nanyang Normal UniversityNanyang 473061China

Transition metal sulfides have great potential as anode mterials for sodium-ion batteries(SIBs)due to their high theoretical specific ***,the inferior intrinsic conductivity and large volume variation during sodiation-desodiation processes seriously affect its high-rate and long-cyde performance,unbeneficial for the application as fast-charging and long-cycling SIBs ***,the three-dimensional porous cu_(1.81)S/nitrogen-doped carbon frameworks(cu_(1.81)S/Nc)are synthesized by the simple and facile sol-gel and annealing processes,which can accommodate the volumetric expansion of cu_(1.81)S nanoparticles and accelerate the transmission of ions and electrons during Na^(+)insertion/extraction processes,exhibiting the excellent rate capability(250.6 mA·g^(-1)at 20.0 A·g^(-1))and outstanding cycling stability(70% capacity retention for 6000 cycles at 10.0 A·g^(-1))for ***,the Na-ion full cells coupled with Na_(3)V_(2)(PO_(4))_(3)/c cathode also demonstrate the satisfactory reversible specific capacity of 330.5 mAh·g^(-1)at 5.0 A·g^(-1)and long-cycle performance with the 86.9% capacity retention at 2.0 A·g^(-1)after 750 *** work proposes a promising way for the conversionbased metal sulfides for the applications as fast-charging sodium-ion battery anode.

关键词： copper sulfide nanoparticles porous carbon framework fast charging long-cycle performance sodium-ion full batteries

Si-c Foam Porous-Medium combustion Power-Generation System for Low-calorific-Value Biomass Syngas

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2025年第1期34卷 206-222页

作者： yANG Jianwen chen Wei cAO Bingwei LIU Xinhui LI Hang college of Mechanical and Aerospace Engineering Jilin University School of Mechanical and Vehicle Engineering Changchun University

Syngas produced from the gasification of organic feedstocks from biomass is one of the clean and sustainable sources of *** advantages of simple access and renewability of biomass energy can meet the energy needs of temporary power *** study presents a biomass power-generation system for vehicular *** biomass and a free-piston Stirling engine generator（FPSEG） as the primary material and prime mover,respectively,biomass energy is converted into electricity by combusting the syngas to heat the *** and key parameter design for biomass gasification and thermoelectric conversion systems within a power generation system were performed.A porous medium area was constructed using Si-c foam ceramics to obtain an energy-conversion experimental *** effects of bed height,porosity,porous-region diameter,and air-intake conditions on the power-generation performance were investigated,and optimisations were performed for the thermoelectric conversion *** rate of increase during FPSEG power generation first increased and then decreased with increasing bed height,peaking at a bed height of 40 *** increasing porous-region diameter accelerated FPSEG power generation,whereas porosity changes in the porous media did not significantly affect the rate of change during FPSEG power *** increasing air intake,the rate of increase during power generation first increased and then *** maximum change rate and the highest thermoelectric conversion efficiency of the power-generation system occurred at 9.5 m3/h and 6.5 m3/h（～45.1%）air intakes,*** the thermal inertia and combustion structure of the thermoelectric conversion system significantly increased the power-generation rate of the system,with 1.8 W/s being observed at a 9.7 m3/h air intake.

关键词： biomass combined heat and power (cHP) gasification porous media combustion power generation

Revisiting the intraseasonal,interannual and interdecadal variability of tropical cyclones in the western North Pacific

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Atmospheric and Oceanic Science Letters 2018年第2期11卷 198-208页

作者： LI Richard c.y. ZHOU Wen city University of Hong Kong Shenzhen Research Institute Shenzhen China School of Energy and Environment Guy Carpenter Asia-Pacific Climate Impact Center City University of Hong Kong Hong Kong China

This paper reviews the recent progress and research on the variability of tropical cyclones(Tcs) at different time scales. Specific focus is placed on how different types of external forcings or climatic oscillations contribute to Tc variability in the western North Pacific(WNP). At the intraseasonal scale, recent advances on the distinctive impacts of the Madden–Julian Oscillation(MJO), the Quasi-biweekly Oscillation, and the asymmetric MJO modulation under different El Ni?o–Southern Oscillation(ENSO) states, as well as the influences of the Pacific–Japan teleconnection, are highlighted. Interannually, recent progress on the influences of the ENSO cycle, different flavors of ENSO, and impacts of Indian Ocean warming is presented. In addition, the uncertainty concerning interdecadal Tc variations is discussed, along with the recently proposed modulation mechanisms related to the zonal sea surface temperature gradient, the North Pacific Gyre Oscillation, and the Pacific Decadal Oscillation(PDO). It is hoped that this study can deepen our understanding and provide information that the scientific community can use to improve the seasonal forecasting of Tcs in the WNP.

关键词： Tropical cylones intraseasonal oscillation ENSO Pacific-Japan teleconnection

Boosting cationic and anionic redox activity of Li-rich layered oxide cathodes via Li/Ni disordered regulation

在线全文

学校读者我要写书评

暂无评论

Journal of Energy chemistry 2025年第1期100卷 533-543页

作者： Zewen Liu Zhen Wu Hao Wang Xudong Zhang yuanzhen chen yongning Liu Shengwu Guo Shenghua chen yanli Nan yan Liu State Key Laboratory for Mechanical Behavior of Materials Xi'an Jiaotong University School of Materials Science and Engineering Xi'an University of Architecture and Technology Hefei Advanced computing center Operation Management corp Ltd Network Information center Xi'an Jiaotong University

Lithium-rich layered oxides （LLOs） are increasingly recognized as promising cathode materials for nextgeneration high-energy-density lithium-ion batteries （LIBs）.However,they suffer from voltage dec.y.and low initial coulombic efficiency （IcE） due to severe structural degradation caused by irreversible O ***,we introduce a three-in-one strategy of increasing Ni and Mn content,along with Li/Ni disordering and TM–O covalency regulation to boost cationic and anionic redox activity simultaneously and thus enhance the electrochemical activity of *** target material,Li1.2Ni0.168Mn0.558co0.074O2（L1）,exhibits an improved IcE of 87.2%and specific capacity of 293.2 mA h g-1and minimal voltage dec.y.of less than 0.53 m V cycle-1over 300 cycles at 1c,compared to Li1.2Ni0.13Mn0.54co0.13O2（Ls）(274.4 mA h g-1for initial capacity,73.8%for IcE and voltage dec.y.of 0.84 mV/cycle over 300 cycles at 1c).Theoretical calculations reveal that the density of states （DOS） area near the Fermi energy level for L1 is larger than that of Ls,indicating higher anionic and cationic redox reactivity than ***,L1 exhibits increased O-vacancy formation energy due to higher Li/Ni disordering of 4.76%（quantified by X-ray diffraction Rietveld refinement） and enhanced TM–O covalency,making lattice O release more difficult and thus improving electrochemical *** increased Li/Ni disordering also leads to more Ni2+presence in the Li layer,which acts as a pillar during Li+de-embedding,improving structural *** research not only presents a viable approach to designing low-co LLOs with enhanced capacity and IcE but also contributes significantly to the fundamental understanding of structural regulation in high-performance LIB cathodes.

关键词： Ice

Effect of Quercetin on Formation of choroidal Neovascularization (cNV) in Age-related Macular Degeneration (AMD)

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Eye Science 2011年第1期26卷 23-29页

作者： George c.y. chiou Institute of Ocular Pharmacology College of MedicineTexas A&M Health Science CenterCollege StationTX 77843USA

Purpose:Age-related macular degeneration(AMD)as a disease entity is "dry" at early stage and made up of two main components at late stage:atrophic AMD and exudative *** acts as an anti-oxidant to protect retinal pigment epithelial cells(RPE)from damaged by oxidative stress,but its effect on formation of choroidal neovascularization(cNV)in AMD is *** aim of this study is to investigate the effect of quercetin on the formation of cNV in ***:The development of cNV induced by laser was *** fluorescein angiography(FA).colored microsphere technique was used to determine the choroidal blood flow in ocular hypertensive rabbit *** in vitro studies,HUVEcs were treated with NaIO3,H2O2 and NaN3 to induce oxidative cell *** effect of quercetin on various oxidations-induced injuries in HUVEcs was measured by MTT *** migration was assessed using a wound healing ***:Quercetin significantly inhibited the formation of laser-induced *** choroidal blood flow in rabbit eyes was significantly increased after quercetin *** vitro results showed quercetin enhanced various oxidations-induced injuries in HUVEcs and inhibited migration of HUVEcs during wound ***:Quercetin inhibited the formation of cNV both in vivo and in vitro and increased choroidal blood *** could become a promising candidate for the treatment of AMD.

关键词：槲皮素年龄相关新生血管 AMD 脉络膜变性黄斑氧化应激损伤