检索结果-南通市图书馆

Penile prosthesis implantation and tunica albuginea incision without grafting in the treatment of Peyronie＇s disease with erectile dysfunction

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

Asian Journal of Andrology 2013年第3期15卷 391-394页

作者： Miroslav L Djordjevic vladimir Kojovic School of Medicine University of Belgrade Belgrade 11000 Serbia

We evaluated penile prosthesis implantation with tunica albuginea-relaxing incisions without grafting in the treatment of Peyronie＇s disease associated with erectile dysfunction. Between April 2005 and June 2011, 62 patients underwent surgery due to severe Peyronie＇s disease associated with erectile dysfunction. Malleable and inflatable penile prostheses were inserted in 49 and 13 cases, respectively. Penile prostheses were inserted into the corpora cavernosa using the standard ventral approach. After lifting the neurovascular bundle, the tunica albuginea was incised and opened at the plaque region to correct the deformities and to lengthen the penis. Subsequently, the wide neurovascular bundle was replaced, and all incisions of the tunica albuginea were covered to prevent corporal grafting. In the median follow-up of 35 months （range 14-82 months）, the penis was completely straightened in 59 （95%） patients. Numbness of the glans, which the patients found initially upsetting, decreased or disappeared spontaneously 3-6 months later. Penile prosthesis implantation with tunica albuginea incisions is a viable alternative in the treatment of Peyronie＇s disease because the extensive dissection of the neurovascular bundle allows a good approach to the plaque and provides excellent covering of the incised tunica albuginea without additional grafting.

关键词： erectile dysfunction neurovascular bundle penile prosthesis Peyronie's disease tunica albuginea

Transient near tip fields in crack dynamics

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

Science China(Physics,Mechanics & Astronomy) 2011年第7期54卷 1309-1318页

作者： BRATOV vladimir PETROV Yuri UTKIN Alexander Institute of Problems of Mechanical Engineering Russian Academy of SciencesSt.-Petersburg 199178Russia St.-Petersburg State University St.-Petersburg 198504Russia

Transient effects of stress-strain fields in the vicinity of a stationary crack tip under high rate loads are *** analytical solutions to near tip stresses are compared to fields prescribed by leading terms(one or several) of Williams asymptotic *** of load application mode,time(or,which is the same,distance from a crack tip) and Poisson's ratio on this discrepancy is extensively *** effects connected with crack tip propagation speed are also *** inconsistencies between real(or received in numerical solutions of state *** element computations) crack tip fields and stress intensity factor(SIF) singular field observed by numerous researchers are *** scope of problems where SIF field can be used for correct prediction of dynamic stress-strain fields in the crack tip region is *** to correctly approximate fields that are not SIF dominated,accounting additional terms of Williams expansion,is studied.

关键词： transient crack tip fields dynamic fracture high-rate loads asymptotic expansions

Power system restoration:a literature review from 2006 to 2016

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2016年第3期4卷 332-341页

作者： Yutian LIU Rui FAN vladimir TERZIJA Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education Shandong UniversityJinan 250061China Department of Electrical and Electronic Engineering University of ManchesterManchester M139PLUK

Power system restoration has attracted more attention and made great progress recently. Research progress of the power system restoration from 2006 to 2016 is reviewed in this paper, including black-start, network reconfiguration and load restoration. Some emerging methods and key techniques are also discussed in the context of the integration of variable renewable energy and development of the smart grid. There is a long way to go to achieve automatic self-healing in bulk power systems because of its extreme complexity. However, rapidly developing artificial intelligence technology will eventually enable the step-by-step dynamic decision-making based on the situation awareness of supervisory control and data acquisition systems(SCADA) and wide area measurement systems(WAMS) in the near future.

关键词： Large-scale blackout Power system restoration Self-healing Smart grid Renewable energy Wide area measurement system(WAMS) Cyber attack

Periodical zonal character of damage near the openings inhighly-stressed rock mass conditions

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2016年第2期8卷 164-169页

作者： vladimir VMakarov Mikhail AGuzev vladimir NOdintsev Lyudmila SKsendzenko Far-Eastern Federal University VladivostokRussia Russian Academy of Sciences MoscowRussia

Rock mass damage at great depths near underground openings is often of a zonal ***,the classical elastoplastic theory fails to explain sufficiently all properties of zonal failure structures.A new non-Euclidean mathematical model for highly-stressed rock mass was developed based on the principles of mechanics of defected material and non-equilibrium *** were developed to determine model parameters that provide satisfactory correspondence between the experimental findings concerning faulted zonal structures near openings at great depths and mathematical *** mechanism of this phenomenon was discovered which consisted in a periodical character of stresses in the surrounding rock mass and development of tensile macrocracks at zones of maximal tangential *** relationships between the cracking zone width and rock mass strength were established.

关键词： Rock failure Openings Zones Modeling

Kinetics of oxidative coupling of methane:Bridging the gap between comprehension and description

在线全文

学校读者我要写书评

暂无评论

Journal of Natural Gas Chemistry 2009年第3期18卷 273-287页

作者： Mikhail Sinev Zukhra Fattakhova vladimir Lomonosov Yurii Gordienko Semenov Institute of Chemical Physics ZAO "SCHAG" Company

The development of notions about the mechanism of the oxidative coupling of methane （OCM） over oxide catalysts and corresponding progress in its kinetic description are reviewed and discussed. The latter becomes essential at the stage of scaling up and optimization of the process in pilot and industrial reactors. It is demonstrated that the main achievements in the development of kinetic models can be reached by combining the approaches conventionally used in homogeneous gas-phase kinetics and in heterogeneous catalysis. In particular, some important features of the OCM process can be described if several elementary reactions of free radical species （formation and transformation） with surface active sites are included into the detailed scheme of methane oxidation in gas. However, some important features, such as a non-additive character of the reciprocal influence of methane and ethane in the case of their simultaneous presence in the reaction mixture, cannot yet be described and comprehended in the framework of schemes developed so far. Possible ways towards an advanced kinetic model, accounting the main principles of catalyst functioning （redox nature of active sites） and pathways of product formation （via free radicals） are traced.

关键词： natural gas methane oxidative coupling of methane ethane ethylene kinetics mechanism rate equations

Analysis of Bingham fluid radial flow in smooth fractures

在线全文

学校读者我要写书评

暂无评论

Journal of Rock Mechanics and Geotechnical Engineering 2020年第5期12卷 1112-1118页

作者： Liangchao Zou Ulf Håkansson vladimir Cvetkovic Division of Resources Energy and InfrastructureDepartment of Sustainable DevelopmentEnvironmental Science and EngineeringRoyal Institute of TechnologyStockholm10044Sweden Division of Soil and Rock Mechanics Department of Civil and Architectural EngineeringRoyal Institute of TechnologyStockholm10044Sweden Skanska Sweden AB Stockholm11274Sweden

Solutions for radial flow of a Bingham fluid are analyzed in this *** aims to eliminate confusions in the literature concerning the plug flow region in different solutions for analysis and design of grouting in rock *** analyses based on the force balance equation reveal that the plug flow region in Bingham radial flow is independent of the fracture radius,and is not a growth function adapted from the solution of one-dimensional(1D)slit flow according to‘similarity’.Based on the shear stress distribution,we analytically proposed that a non-uniform plug flow region cannot *** Bingham fluid(grout)penetration and flowrate evolution as functions of grouting time are given using the correct expression for the plug flow *** radius-independent plug flow region and the presented flowrate evolution equation are also verified *** radial flow,the relative penetration length is equal to the relative width of plug flow region,which is the same as that for 1D channel *** in analytical solutions for grout penetration and flowrate evolution were also *** clarification of the plug flow region and evaluation of discrepancies in analytical solutions presented in this work could simplify modeling and design of grouting in rock engineering applications.

关键词： Rock grouting Radial flow of Bingham fluids Plug flow region Force balance Energy dissipation Analytical solution

Structure,mechanical characteristics,biodegradation,and in vitro cytotoxicity of magnesium alloy ZX11 processed by rotary swaging

在线全文

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2020年第4期8卷 1038-1046页

作者： Natalia Martynenko Natalia Anisimova Mikhail Kiselevskiy Natalia Tabachkova Diana Temralieva Dmitry Prosvirninb vladimir Terentiev Andrey Koltygina vladimir Belov Mikhail Morosov vladimir Yusupov Sergey Dobatkina National University of Science and Technology"M1SIS" Leninsky prospect4119049 MoscowRussia A.A.Baikov Institute of Metallurgy and Materials Science of the RAS Leninsky prospect49119334 MoscowRussia ≪N.N.Blokhin National Medical Research Center of Oncology≫of the Ministry of Health of the Russian Federation Kashirskoye Highway23115478 MoscowRussia A.M.Prokhorov General Physics Institute of the RAS Vavilova st.3&Moscow 119991、Russia 5.Department of Materials Science and EngineeringMonash UniversityClaytonMelbourne VIC 3800Australia 6.Department of Mechanical EngineeringThe University of Western AustraliaCrawleyPerth WA 6009Australia

Rotary swaging(RS)of alloy Mg-1.03Zn-0.66Ca(ZX11)was shown to refine the average grain size to 4.5±1.2μm in a longitudinal section and 4.8±0.9μm in a transverse *** addition,a small amount of Mg2Ca particles about 300nm in size and Mg6Zn3Ca2 particles with a size of about lOOnm was *** resulted in pronounced strengthening:the yield strength and the ultimate tensile strength rose to 210±8 MPa and 276±6 MPa,respectively,while the elongation hardly decreased(22.0±1.8% and 18.3±2.9% before and after RS).Furthermore,RS led to an increase in the fatigue limit of the alloy from 120 MPa to 135 MPa and did not impair its resistance to chemical *** studies in vitro showed that ZX11 induces hemolysis without inhibiting the viability of peripheral blood mononuclear cells and has a more pronounced cytotoxic effect on tumor cells in comparison with non-transformed *** significant difference of the latter effect between the initial and the deformed states was observed.

关键词： Magnesium alloy Rotary swaging Mechanical characteristics Hemolysis Cell viability Cytotoxicity

COMPACT DIFFERENCE SCHEMES FOR THE DIFFUSION AND SCHRODINGER EQUATIONS. APPROXIMATION, STABILITY, CONVERGENCE, EFFECTIVENESS, MONOTONY

在线全文

学校读者我要写书评

暂无评论

Journal of Computational Mathematics 2014年第3期32卷 348-370页

作者： vladimir A. Gordin Eugeny A. Tsymbalov National Research University Higher School of Economics Hydrometeorological Center of Russia Moscow 123242 Russia

Various compact difference schemes （both old and new, explicit and implicit, one-level and two-level）, which approximate the diffusion equation and SchrSdinger equation with periodical boundary conditions are constructed by means of the general approach. The results of numerical experiments for various initial data and right hand side are presented. We evaluate the real order of their convergence, as well as their stability, effectiveness, and various kinds of monotony. The optimal Courant number depends on the number of grid knots and on the smoothness of solutions. The competition of various schemes should be organized for the fixed number of arithmetic operations, which are necessary for numerical integration of a given Cauchy problem. This approach to the construction of compact schemes can be developed for numerical solution of various problems of mathematical physics.

关键词： Compact schemes Pairs of test functions Courant number Two-level scheme,Order of convergence Effectiveness Monotony.

Numerical study on the characteristics of natural supercavitation by planar symmetric wedge-shaped cavitators for rotational supercavitating evaporator

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

Science China(Technological Sciences) 2015年第6期58卷 1072-1083页

作者： ZHENG ZhiYing LI FengChen LI Qian KULAGIN vladimir A School of Energy Science and Engineering Harbin Institute of Technology Department of Heat Technology and Fluid Dynamics Siberian Federal University

With the application of supercavitation effect, a novel device named rotational supercavitating evaporator(RSCE) was recently designed for desalination. In order to improve the blade shape of rotational cavitator in RSCE for performance optimization and then design three-dimensional blades, numerical simulations are conducted on the supercavitating flows(with cavitation number ranging from 0.055 to 0.315) around two-dimensional planar symmetric wedge-shaped cavitators with different wedge angles varied from 10 to 180 degrees. Proper numerical method for simulating supercavitating flows around planar symmetric cavitator is established, and assessment of k-ε-v2 -f turbulence model in simulating cavitating flows is conducted. It shows that the size of computational domain would affect the simulation result. Empirical formulae for supercavity dimensions about cavitation number at different wedge angles are obtained, which are of significant importance in the subsequent design of three-dimensional blade. The characteristics of resistance at different wedge angles are discussed, which, together with the characteristics of supercavity dimensions, play important roles in the optimal design of RSCE.

关键词： rotational supercavitating evaporator desalination planar symmetric wedge-shaped cavitators CFD numerical simulation