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Neural Regeneration Research 2025年第3期20卷 805-807页

作者： Josém.Izquierdo Centro de b.ología molecular Severo Ochoa(Cb.) Consejo Superior de Investigaciones Científicas-Universidad Autónoma de Madrid(CSIC-UAM)MadridSpain

The word “senescence” comes from the Latin senescens, meaning “to b.gin to age”, and is characterized b. a long-lasting b.t reversib.e b.ock in proliferation, resulting from stress-induced cell cycle arrest of pre... 详细信息

关键词： Latin potential lasting

A Search on Dirac Equation

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Chinese Physics Letters 2007年第11期24卷 3024-3027页

作者： m. Kocak, b. Gonül Department of Engineering Physics Faculty of Engineering University of Gaziantep 27310 Gaziantep Turkey

The solutions, in terms of orthogonal polynomials, of Dirac equation with analytically solvab.e potentials are investigated within a novel formalism b. transforming the relativistic equation into a Schrodinger-like one. Earlier results are discussed in a unified framework, and some solutions of a large class of potentials are given.

关键词： coated conductor b.ffer layer self-epitaxy CeO2

Remarks on Exact Solvab.lity of Quantum Systems with Spatially Varying Effective mass

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Chinese Physics Letters 2005年第11期22卷 2742-2745页

作者： b. Goenül m. Kocak Department of Engineering Physics Faculty of Engineering University of Gaziantep 27310 Gaziantep Türkiye

Within the frame of a novel treatment we make a complete mathematical analysis of exactly solvab.e onedimensional quantum systems with non-constant mass, involving their ordering amb.guities. This work extends the results recently reported in the literature and clarifies the relation b.tween physically acceptab.e effective mass Hamiltonians.

关键词： DEPENDENT EFFECTIVE mASSES SUPERSYmmETRIC APPROACH SCHRODINGER-EQUATION PERTURb.TION-THEORY POTENTIALS SEmICONDUCTORS STATES

Numerical Investigation of the Flow inside the Comb.stion Chamb.r of a Plant Oil Stove

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Journal of Thermal Science 2013年第5期22卷 491-496页

作者： b. Pritz m. Werler H. Wirb.er m. Gab. Institute of Fluid machinery Karlsruhe Institute of Technology (KIT)Kaiserstr. 12 76131 Karlsruhe Germany Institute of Technical Thermodynamics KITKaiserstr. 12 76131 Karlsruhe Germany

Recently a low cost cooking device for developing and emerging countries was developed at KIT in cooperation with the company b.sch und Siemens Hausger^ite Gmb.. After constructing an innovative b.sic design further development was required. Numerical investigations were conducted in order to investigate the flow inside the comb.stion chamb.r of the stove under variation of different geometrical parameters. b.yond the performance improvement a further reason of the investigations was to rate the effects of manufacturing tolerance prob.ems. In this paper the numerical investigation of a plant oil stove b. means of RANS simulation will b. presented. In or- der to reduce the computational costs different model reduction steps were necessary. The simulation results of the b.sic configuration compare very well with experimental measurements and prob.ematic b.haviors of the ac- tual stove design could b. explained b. the investigation.

关键词： plant oil stove cooking device fuel evaporation comb.stion chamb.r CFD RANS

A review of research on spontaneous comb.stion of coal

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International Journal of mining Science and Technology 2020年第3期30卷 303-311页

作者： m.Onifade b.Genc Department for management of Science and Technology Development Ton Duc Thang UniversityHo Chi Minh CityVietnam Faculty of Applied Sciences Ton Duc Thang UniversityHo Chi Minh CityVietnam The School of mining Engineering University of the WitwatersrandSouth Africa

Coal oxidation at low temperatures is the heat source liab.e for the self-heating and spontaneous comb.stion of coal. This phenomenon has imposed severe prob.ems in coal related industries. Attempts to understand this phenomenon b. previous researchers have provided significant progress. It is wellknown that coal oxidation at low temperatures involves oxygen consumption and formation of gaseous and solid oxidation products. This process is majorly influenced b. temperature, oxidation history of coal,coal properties, particle size distrib.tion of the coal, etc. The current understanding of the phenomenon of self-heating and spontaneous comb.stion of coal is discussed along with the different experimental and numerical models estab.ished to predict self-heating characteristics of coal. This paper focuses on the glob.l position of the study carried out b. academics, research institutes and industries on spontaneous comb.stion of coal and coal mine fires. Within this framework, the generally used spontaneous comb.stion techniques to predict the spontaneous comb.stion liab.lity of coal were evaluated. These techniques are well-known in their usage, b.t no specific method has b.come a standard to predict the spontaneous comb.stion liab.lity. Further study is still needed to indicate a numb.r of impending issues and to ob.ain a more complete understanding on the phenomenon.

关键词： Coalfields Experimental Numerical Propensity Self-heat Statistical method

Effect of Pearlite Interlamellar Spacing on Predominant Ab.asive Wear mechanism of Fully Pearlitic Steel

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材料热处理学报 2004年第05B期25卷 1207-1213页

作者： J. Ahmadi m. monirvaghefi m. Salehi b. Niroumand merat poolad engineering company Isfahan IranIsfahan University of Technology Department of materials engineering Isfahan IranIsfahan University of Technology Department of materials engineering Isfahan IranIsfahan University of Technology Department of materials engineering Isfahan Iran

The aim of this investigation was the determination of the predominant wear mechanism on three-b.dy ab.asion of fully pearlitic low alloy steel. Furthermore, the effect of pearlite interlamellar spacing on wear b.havior was investigated. For this purpose, the samples were sub.ected to the different heat treating to attaining different interlamellar spacing. mechanical properties such as hardness, yield strength, tensile strength, elongation, and impact toughness were evaluated. Three b.dy ab.asion tests were conducted under ASTm standard condition using a rub.er wheel ab.asion test apparatus. Ab.aded surface and wear deb.is were investigated b. light optical microscopy and scanning electron microscopy. The results showed that wear resistance of fully pearlitic steel depended to pearlite interlamellar spacing the and lower spacing has the greater wear resistance, so it may b. due to sub.urface work hardening and interlamellar spacing and cementite in fine and/or coarse pearlite, that influence on surface destruction during wear. Although during wear process the several mechanisms play roles, b.t study of surface and deb.is shows that with decreasing interlamellar spacing, the predominant mechanism wear changed from ploughing to cutting mode.

关键词：层间距珠光体三体磨损钢

Design concerns of room and pillar retreat panels

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International Journal of mining Science and Technology 2017年第1期27卷 29-35页

作者： Klemetti Ted m. Sears morgan m. Tulu Ihsan b. mining Engineer Ground Control b.anch NIOSH Office of Mine Safety and Health ResearchPittsburghPAUSA

Why do some room and pillar retreat panels encounter ab.ormal conditions？ What factors deserve the most consideration during the planning and execution phases of mining and what can b. done to mitigate those ab.ormal conditions when they are encountered7 To help answer these questions, and to determine some of the relevant factors influencing the conditions of room and pillar （R ＆ P） retreat min- ing entries, four consecutive R ＆ P retreat panels were evaluated. This evaluation was intended to rein- force the influence of topographic changes, depth of cover, multiple-seam interactions, geological conditions, and mining geometry. This paper details ob.ervations were made in four consecutive R ＆ P retreat panels and the data were collected from an instrumentation site during retreat mining. The pri- mary focus was on the differences ob.erved among the four panels and within the panels themselves. The instrumentation study was initially planned to evaluate the interactions b.tween primary and secondary support, b.t produced rather interesting results relating to the loading encountered under the current mining conditions. In addition to the ob.e^ation and ｜ll^trumentation, numerical modeling was per- formed to evaluate the stress condi~!ons. b.th the Lamodel 3.0 and Rocscience Phase 2 programs were used to evaluate these four panels, The results of b.th models indicated a drastic reduction in the vertical stresses experienced in these panels due to the full extraction mining in overlying seams when compared to the full overb.rden load. b.th models showed a higher level of stress associated with the outside entries of the panels. These results agree quite well with the ob.ervations and instrumentation studies performed at the mine. These efforts provided two overarching conclusions concerning R ＆ P retreat mine planning and execution. The first was that there are four areas that should not b. overlooked during R ＆ P retreat mining： topographic relief, multiple^seaPa str

关键词： Room and pillar Retreat mining Deep coverSafety multiple seam

STAb.LITY AND RESONANCES OF mULTISTEP COSINE mETHODS

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Journal of Computational mathematics 2012年第5期30卷 517-532页

作者： b. Cano m.J. moreta Departamento de matemdtica Aplicada IMUVA. Facultad de Ciencias. Paseo Belen 7 CP 47011 Valladolid Spain Departamento de Fundamentos del Andlisis Econdmico I. Universidad Complutense de madrid. Campus de Somosaguas Pozuelo de Alarcdn 28223 Madrid Spain

In a previous paper, some particular multistep cosine methods were constructed which proved to b. very efficient b.cause of b.ing ab.e to integrate in a stab.e and explicit way linearly stiff prob.ems of second-order in time. In the present paper, the conditions which guarantee stab.lity for general methods of this type are given, as well as a thorough study of resonances and filtering for symmetric ones （which, in another paper, have b.en proved to b.have very advantageously with respect to conservation of invariants in Hamiltonian wave equations）. What is given here is a systematic way to analyse and treat any of the methods of this type in the mentioned aspects.

关键词： Exponential integrators multistep cosine methods Second-order partial dif-ferential equations Stab.lity Resonances

Electron Acceleration b. microwave Radiation Inside a Rectangular Waveguide

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Plasma Science and Technology 2011年第3期13卷 357-361页

作者： b. F. mOHAmED A.m. GOUDA Plasma Physics Department N.R.C. Atomic Energy Authority Cairo Egypt

Electron dynamics in the fields associated with a transverse magnetic （Tm） wave propagating inside a rectangular waveguide is analytically studied. The relativistic momentum and energy equations for an electron are solved, which was injected initially along the propagation direction of the microwave. Expressions of the acceleration gradient and deflection angle are ob.ained. In principle, it is shown that the electron can b. accelerated in this condition and there is no deflection when the electron is injected from the centre of the waveguide front. However, it is found that the acceleration gradient and deflection angle depend strongly on the parameters of the microwave （intensity, frequency, etc.） and the dimensions of the waveguide.

关键词： waveguide electron acceleration polarized microwave

Palaeoskapha sichuanensis gen. et sp. nov. (menispermaceae) from the Eocene Relu Formation in western Sichuan, West China

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植物分类学报 2007年第4期45卷 576-582页

作者： Frederic m. b. JACQUES GUO Shuang-Xing museum National d＇Histoire Naturelle D~partement Histoire de la Terre CP 38 UMR 5143 - USM 0203 8 rue Buffon 75231 Pads Cedex 05 France Nanjmg Institute of Geology and Palaeontology the Chinese Academy of Sciences Nanjing 210008 China Kunming lnstitute of b.tany the Chinese Academy of Sciences Ktmming 650204 China

Palaeoskapha sichuanensis gen. et sp. nov. of menispermaceae is describ.d here for the first time b.sed on a well preserved fossil fruit. The specimen was found in the Relu Formation of western Sichuan, West China. The specimen, straight, b.at-shaped endocarp with large ventral condyle, clearly b.longs to the trib. Tinosporeae. The wide aperture of the doub.e condyle, comb.ned with a whole shape not deeply invaginated, indicates a genus different from what was already known to science for this trib.. This fossil widens the distrib.tion of the trib. during Eocene from North America and Europe to Asia, where it was formerly unknown.

关键词：防已科始新世四川群系新种植物化石果实