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Impact of Clocking on the Aero-Thermodynamics of a second stator tested in a One and a Half stage HP Turbine

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Journal of Thermal science 2008年第2期17卷 97-110页

作者： N.Billiard g.Paniagua R.Dénos Turbomachinery and Propulsion Department von Karman Institute for Fluid Dynamics

This paper focuses on the experimental investigation of the time-averaged and time-accurate aero- thermodynamics of a second stator tested in a 1.5 stage high-pressure turbine. The effect of clocking on aerodynamic and heat transfer are investigated. Tests are performed under engine representative conditions in the VKI compression tube CT3. The test program includes four different clocking positions, i.e. relative pitch-wise positions between the fh-st and the second stator. Probes located upstream and downstream of the second stator provide the thermodynamic conditions of the flow field. On the second stator airfoil, measurements are taken around the blade profile at 15, 50 and 85% span with pressure sensors and thin-film gauges. Both time-averaged and time-resolved aspects of the flow field are addressed. Regarding the time-averaged results, clocking effects are mainly observed within the leading edge region of the second stator, the largest effects being observed at 15% span. The surface static pressure distribution is changed locally, hence affecting the overall airfoil performance. For one clocking position, the thermal load of the airfoil is noticeably reduced. Pressure fluctuations are attributed to the passage of the up- stream transonic rotor and its associated pressure gradients. The pattern of these fluctuations changes noticeably as a function of docking. The time-resolved variations of heat flux and static pressure are analyzed together showing that the major effect is due to a potential interaction. The time-resolved pressure distribution integrated along the second stator surface yields the unsteady forces on the vane. The magnitude of the unsteady force is very dependent on the clocking position.

关键词： transonic flow turbines stator clocking forces heat transfer.

CFD simulation of a Hydrogen/Argon Plasma Jet Reactor for Coal Pyrolysis

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Chemical Research in Chinese Universities 2004年第4期20卷 446-451页

作者： CHEN H. g. XIE K. C. Taiyuan University of Technology Taiyuan University of Technology Taiyuan 030024 P. R. China City University London EC1V 0HB UKand Taiyuan 030024 P. R. China

A Computational Fluid Dynamics(CFD) model was formulated for DC arc hydrogen/argon plasma jet reactors used in the process of the thermal H_2/Ar plasma pyrolysis of coal to acetylene. In this model, fluid flow, convective heat transfer and conjugate heat conductivity are considered simultaneously. The error caused by estimating the inner-wall temperature of a reactor is avoided. The thermodynamic and transport properties of the hydrogen/argon mixture plasma system, which are usually expressed by a set of discrete data, are fitted into expressions that can be easily implemented in the program. The effects of the turbulence are modeled by two standard k-εequations. The temperature field and velocity field in the plasma jet reactor were calculated by employing sIMPLEsT algorithm. The knowledge and insight obtained are useful for the design improvement and scale-up of plasma reactors.

关键词： Plasma Reactor Computational fluid dynamics Coal pyrolysis

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事件层的保存潜力探讨

沉积学报 2001年第1期19卷 7-12页

作者： s.g.Pemberton 周志澄 J.MacEachern 加拿大艾伯塔大学地球和大气科学系中国科学院南京地质古生物研究所南京210008 加拿大西蒙弗雷泽大学地球科学系

影响事件层保存潜力的主要因素有 :纯粹的沉积速率、生物成因的混合速率以及机械改造的规模 ,可以从时间规模 (过渡时间和消除时间 )的角度来考虑事件层保存潜力。基底的机械改造同样对于事件层和正常天气下的沉积物的保存具有重要影响... 详细信息

影响事件层保存潜力的主要因素有 :纯粹的沉积速率、生物成因的混合速率以及机械改造的规模 ,可以从时间规模 (过渡时间和消除时间 )的角度来考虑事件层保存潜力。基底的机械改造同样对于事件层和正常天气下的沉积物的保存具有重要影响。综合分析影响事件层保存潜力的各种因素表明 ,在近基的临滨带中、上部及滨外带下部 ,事件层具有较高的保存潜力 ,而在近基及远基两端之间的临滨带下部及滨外带上部。

关键词：事件层保存潜力过渡时间消除时间机械改造沉积速率生物成因事件地层学

Flow and heat transfer over hyperbolic stretching sheets

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Applied Mathematics and Mechanics(English Edition) 2012年第4期33卷 445-454页

作者： A. AHMAD s. AsgHAR COMsATs Institute of Information Technology Department of Mathematics King Abdulaziz University

The boundary layer flow and heat transfer analysis of an incompressible viscous fluid for a hyperbolically stretching sheet is presented. The analytical and numer- ical results are obtained by a series expansion method and a local non-similarity （LNs） method, respectively. The analytical and numerical results for the skin friction and the Nusselt number are calculated and compared with each other. The significant observation is that the momentum and the thermal boundary layer thickness decrease as the distance from the leading edge increases. The well-known solution of linear stretching is found as the leading order solution for the hyperbolic stretching.

关键词： hyperbolic stretching sheet boundary layer flow heat transfer seriesexpansion method local non-similarity method

Effects of some Thiol Chelators on Enzymatic Activities in Blood, Liver and Kidneys ofAcute Arsenic (Ⅲ) Exposed Mice

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Biomedical and Environmental sciences 1998年第1期11卷 38-45页

作者： NEELIMATRIPATHI s.J.sFLORA DivisionofPharmacologyandToxicology DefenceResearchandDevelopmentEstablishmentGwalior－474002India D

The effects of meso 2, 3-dimercaptosuccinic acid (DMsA), sodium 2, 3 dimercaptopropane 1-sulfonate (DMPs) and s-adenosyl L-methionine (sAM) on the enzymatic activities of mice were studied. The mice were given intraperitoneal (i. p. ) injections of these chelating agents (1 mmol/kg) and 3 h later the activity of 8-aminolevulinic acid dehydratase (ALAD) in the blood, and aspartate aminotransferase (AsT), alanine aminotransferase (ALT), γ-glutamyltranspeptidase (γ-gT), alkaline phosphatase (ALP) in the liver and kidney were determined. The activity of blood ALAD was significantly increased by the administration of DMsA and sAM while DMPs had only a moderate effect. The activities of other hepatic enzymes changed little when the mice were treated with these chelating agents, except for a significant reduction in hepatic ALP activlty following DMPs administration. Arsenic (Ⅲ) administration markedly increased the activities of ALT and ALP in the liver and kidneys. The changes in the enzymatic activities by treatment with arsenic were prevented by injection of DMsA,DMPs and sAM, DMsA being the most effective. These results indicate that DMsA, DMPs and sAM were not toxic to the liver or kidneys of mice and that treatment with DMsA is more effective than DMPs or sAM in protecting mice from acute hepatic or renal toxicity caused by arsenic.

关键词： ADENOsYL-L-METHIONINE LEAD-INTOXICATION MEsO-2,3-DIMERCAPTOsUCCINIC ACID 2,3-DIMERCAPTOsUCCINIC ACID THERAPEUTIC EFFICACY sODIUM ARsENITE DMsA RATs EXCRETION AgENTs

Pathogenesis and managenent of pain in chronic pancreatitis

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World Journal of gastroenterology 2000年第4期6卷 490-496页

作者： C. s. Pitchumoni Professor of Medicine/Community and Preventive Medicine New York Medical College Director of Medicine and Chief of GastroenterologyOur Lady of Mercy Medical CenterBronxNew York 10466

INTRODUCTIONOf the three cardinal manifestations of chronic pancreatitis-pain,diabetes mellitus and steatorrhea,it is pain thatbrings the patient to the physician and is the most difficultto *** intractabale pain that... 详细信息

关键词： pancreatitis/therapy pain/therapy pain intractable/therapy lithotripsy alcoholics anonymous parenteral nutrition total antioxidants analgesics enzyme inhibitors somatostatin sphincterotomy endoscopic

Comparison analysis of multiple-omics data between female germline stem cells and spermatogonial stem cells

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genes & Diseases 2023年第3期10卷 727-730页

作者： geng g.Tian Jing Li Ji Wu Renji Hospital Key Laboratory for the Genetics of Developmental&Neuropsychiatric Disorders(Ministry of Education)Bio-X InstitutesSchool of MedicineShanghai Jiao Tong UniversityShanghai 200240China Department of Bioinformatics and Biostatistics School of Life Sciences and BiotechnologyShanghai Jiao Tong UniversityShanghai 200240China Key Laboratory of Fertility Preservation and Maintenance of Ministry of Education Ningxia Medical UniversityYinchuanNingxia 750004China

Female germline stem cells(FgsCs)and spermatogonial stem cells(ssCs)are germline stem cells that transmit the genetic material from generation to ***,it is essential to understand the similarities and differences between FgsCs and *** this study,we comprehensively compared the epigenetics of FgsCs and ssCs,including high-order chromatin organization,chromatin histone modification,and transcriptome by analyzing multiple-omics data(Hi-C,ChIP-seq,and RNA-seq).

关键词： ssCs female analysis

基于XeF(C-A)放大器的混合(固态/气态)超高功率飞秒激光系统(英文)

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光学精密工程 2011年第2期19卷 252-259页

作者： LOsEV V ALEKsEEV s IVANOV N KOVALCHUK B MIKHEEVL MEsYATs g PANCHENKO Yu PUCHIKIN A RATAKHIN N YAsTREMsKY A Institute of High Current Electronics of siberian Branch of Russian Academy of sciences aveAkademichesky 2/3Tomsk 634055Russia Lebedev Physical Institute of Russian Academy of sciences Leninsky Prospekt53119991 Russia

提出了基于前端发生器和终端放大器,使用光泵浦XeF（C-A）激活介质的太瓦级混合激光器（THL-100）系统。前端发生器由长532 nm的连续激光泵浦的钛宝石飞秒脉冲振荡器,脉冲展宽机构,532 nm的脉冲激光泵浦的再生多通道放大器,衍射光栅压... 详细信息

提出了基于前端发生器和终端放大器,使用光泵浦XeF（C-A）激活介质的太瓦级混合激光器（THL-100）系统。前端发生器由长532 nm的连续激光泵浦的钛宝石飞秒脉冲振荡器,脉冲展宽机构,532 nm的脉冲激光泵浦的再生多通道放大器,衍射光栅压缩器和二次谐波发生器（KDP）组成。其光束输出参数为：脉冲持续时间50 fs,二次谐波（475 nm）辐射能量5 mJ。前端发生器以10 Hz的单脉冲模式工作。XeF（C-A）放大器由双高压脉冲发生器（线性变压器）,爆炸式阴极发射真空二极管,电子束注入系统,充满Xe的气室转换器和激光单元组成。高压发生器包括12个变压器,每个变压器有8个电容（40 nF）和火花隙,电容可以充电至100 kV。真空二极管中的电子束参数为：总电流300 kA,峰值电压550kV,脉冲持续时间约150 ns。穿透金属箔片到达Xe转换器的6个100 cm×12 cm电子束的总能量为67 kJ。激光系统通过泵浦能量的级联处理导致Xe2＊的快速形成,并在（172±5）nm连续辐射。真空紫外辐射通过CaF2窗口辐射到含有XeF2蒸汽和氮气缓冲气体的激光单元中,使XeF2光解,形成XeF＊准分子。由真空紫外辐射泵浦的放大器激活介质长110 cm,直径为24 cm。文中通过数值模拟给出了输出参数和第一实验结果,根据XeF（C-A）放大器参数模型和增益测量结果,得到的输出能量高达23 J,这意味着50 fs脉冲的峰值功率高达4060 TW。

关键词：混合激光器 XeF(C—A)放大器飞秒脉冲宽度电子束紫外转换器

Viscous dissipation of Rankine vortex profile in zero meridional flow

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Acta Mechanica sinica 2005年第6期21卷 550-556页

作者： Y.Ahoelkassem g.H.Vatistas N.Esmail Department of Mechanical and Industrial Engineering Concordia UniversityMontreal.Quebec H3G 1M8Canada

An analytical solution is given for a time-decay Rankine vortex profile due to viscous effects. The vortex filament is assumed to be isolated, strong, concentrated and having zero-meridional flow （i.e. radial and axial velocities are equal to zero）. Zero-meridional renders the governing equations for an unsteady, incompressible and axisymmetric vortex in a simple form. Based on the tangential momentum equation, the spatial-temporal distributions of the swirl velocity are given in terms of Fourier-Bessel series by using separation of variables technique. A general formula is derived by total differentiation of the swirl velocity with respect to time, depicting the viscous dissipation for Oseen and Taylor-like vortex profiles. This analysis is validated by comparison with previous experimental data.

关键词： Rankine vortex Dissipation Fourier series Monopolar Zero-Meridional