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Thermodynamic Characterization of Planar Shapes and Curves, and the Query of Temperature in Black Holes

Journal of Applied Mathematics and Physics 2021年第8期9卷 2004-2037页

作者： güngö r gündüz Orta Doğ u Teknik Ü niversitesi Ankara Turkey

The purpose of this research is to characterize shapes in thermodynamic terms, namely, in terms of total energy, dissipative energy, entropy, and temperature. As case studies, polygons and some well-known curves were taken, and they were characterized using physical terms. The relation between entropy and curvature was elucidated, and the black hole surface gravity and temperature were criticized and reinterpreted from this point of view. Particular energy attributions were evaluated by comparing the position of any edge of a polygon (i.e. its angle with the horizontal axis) with a broken crystal surface. Energies of all edges were added up at all positions between 0˚ - 360˚. In regular polygons, the total energy decreases with the increase of the number of edges. Entropy increases in the reverse order, and the increase of the number of edges increases entropy. It implies that the circle has the lowest energy but the highest surface entropy. In curves (circle, sine-curve, spiral, and exponential curve), the total energy, dissipative energy, and entropy all depend on amplitude and also on specific variables. Black hole entropy expressed in terms of the surface area is a configurational entropy and not thermal entropy;therefore, it does not involve a varying temperature term. The surface gravity of a black hole is connected to acceleration and thus to curvature. To relate it with the temperature needs to be reinterpreted, because, surface gravity behaves like an attractive force not exactly like temperature. Hawking radiation is still possible, but the black hole does not get warmer as it evaporates. Material loss from the black hole gets faster as its radius decreases due to the curvature effect, i.e. by a mechanism similar to the gibbs-Thomson effect.

关键词： Polygons Curves Viscoelasticity Energy Entropy Temperature Black Hole

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Recycling of spent lithium-ion batteries as a sustainable solution to obtain raw materials for different applications

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Journal of Energy Chemistry 2023年第4期79卷 118-134页

作者： V.M.Leal J.S.ribeiro E.L.D.Coelho M.B.J.g.Freitas Federal University of Espírito Santo Department of ChemistryLaboratory of Electrochemistry and ElectrochemistryAv.Fernando Ferrari514VitóriaES 29075-910Brazil

Lithium-ion batteries(LIBs)containing graphite as anode material and LiCoO_(2),LiMn_(2)O_(4),and LiNi_(x)Mn_(y)Co_(z)O_(2) as cathode materials are the most used worldwide because of their high energy density,capacitance,durability,and ***,such widespread use implies the generation of large amounts of electronic *** is estimated that more than 11 million ton of LIBs waste will have been generated by *** recycling can contribute to minimizing environmental contamination and reducing production costs through the recovery of high-value raw materials such as lithium,cobalt,and *** most common processes used to recycle spent LIBs are pyrometallurgical,biometallurgical,and *** the current scenario,it is necessary to develop environmentally friendly methods to recycle batteries and synthesize materials with multiple technological *** study presents a review of industrial and laboratory processes for recycling spent LIBs and producing materials that can be used in new batteries,energy storage devices,electrochemical sensors,and photocatalytic reactions.

关键词： Li-ion batteries Recycling Cathode Battery Hydrometallurgical Pyrometallurgical

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Effect of high anodic polarization on the passive layer properties of superduplex stainless steel friction stir welds at different chloride electrolyte pH values and temperatures

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International Journal of Minerals,Metallurgy and Materials 2019年第6期26卷 710-721页

作者： L.A.Santa-Cruz g.Machado A.A.Vicente T.F.C.Hermenegildo T.F.A.Santos Department of Mechanical Engineering Universidade Federal de PernambucoAv.da Arquiteturas/n50740-550RecifePEBrazil Center of Nanotechnology Centro de Tecnologias Estratégicas do NordesteCETENERecifePEBrazil Department of Chemical Engineering Universidade de Sao PauloSao PauloSPBrazil

The conditions used for friction stir welding of duplex stainless steels determine the resulting mechanical and corrosion performance of the *** study investigates the corrosion resistance of UNS S32750 and S32760 superduplex stainless steels(SDSSs)joined by friction stir welding,employing cyclic polarization,Mott–Schottky,and microscopy techniques for *** microscopy images indicated the presence of a deleterious intermetallic phase after electrolytic etching of S32760,as well as decreased corrosion *** presence of molybdenum in the steels promoted better passive behavior at low *** Mott–Schottky curves revealed p-n heterojunction behavior of the passive *** acquired after the polarization test by scanning electron microscopy showed higher passivation propensity with increases of temperature and pH.

关键词： superduplex stainless steel friction stir welding corrosion resistance cyclic polarization Mott–Schottky

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Multi-dimensional, light-controlled switch of fluorescence resonance energy transfer based on orderly assembly of 0D dye@micro-micelles and 2D ultrathin-layered nanosheets

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Nano Research 2016年第12期9卷 3828-3838页

作者： Zhixiong Li Ruizheng Liang Simin Xu Wendi Liu Dongpeng Yan Min Wei David g. Evans Xue Duan State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

Fluorescence resonance energy transfer （FRET） systems have broad applications in visual detection, intelligent materials, and biological imaging, all of which favor the transmission of light through multiple dimensions and in diverse directions. Herein, we have demonstrated multi-dimensional （0D and 2D） FRET within a multi-layer ultrathin film （UTF） by employing a layer-by-layer （LBL） assembly technique. The anionic block copolymer micelle poly（tert-butyl acrylate- co-ethyl acrylate-co-methacrylic acid）（PTBEM） is chosen as a molecular carrier for the incorporation of bis（8-hydroxyquinolate） zinc （Znq2） and open-ring merocyanine （MC）（denoted as （Znq2/MC）@PTBEM）. Alternatively, electrostatic assembly is performed with cationic layered double hydroxide （LDH） nanosheets （denoted as [（Znq2/MC）@PTBEM/LDH]n）. This [（Znq2/MC）@PTBEM/ LDH]n system offers a multi-dimensional propagation medium and ensures that the FRET donor and acceptor are located within their F6rster radii in each direction. The system demonstrates a FRET process that can be switched via alternating ultraviolet/visible （UV/vis） irradiation, with tunable blue-green/red fluorescence, resulting in a FRET efficiency as high as 81.7%. It is expected that this assembly method, which uses 0D micelles on a 2D layered material, can be extended to other systems for further development of multi-dimensional FRET.

关键词： bis(8-hydroxyquinolate)zinc (Znq2) open-ring merocyanine layered double hydroxide layer-by-layerself-assembly multi-dimensionalfluorescence resonanceenergy transfer

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CompactPCI/Linux Platform in FTU Slow Control System

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Plasma Science and Technology 2004年第6期6卷 2535-2540页

作者： F.Iannone L.Wang C.Centioli M.Panella g.Mazza V.Vitale AssociazioneEuratom／ENEAsullaFusione CentroRicercheFrascati00044FrascatiItaly InstituteofPlasmaPhysics ChineseAcademyofSciencesHefei230031China

In large fusion experiments, such as tokamak devices, there is a common trendfor slow control systems. Because of complexity of the plants, the so-called 'Standard Model' (SM)in slow control has been adopted on several tokamak machines. This model is based on a three-levelhierarchical control: 1) High-Level Control (HLC) with a supervisory function; 2) Medium-LevelControl (MLC) to interface and concentrate I/O field equipments; 3) Low-Level Control (LLC) withhard real-time I/O function, often managed by PLCs. FTU control system designed with SM concepts hasunderwent several stages of developments in its fifteen years duration of runs. The latestevolution was inevitable, due to the obsolescence of the MLC CPUs, based on VME-MOTOROLA 68030 withOS9 operating system. A large amount of C code was developed for that platform to route the dataflow from LLC, which is constituted by 24 Westinghouse Numalogic PC-700 PLCs with about 8000field-points, to HLC, based on a commercial Object-Oriented Real-Time database on Alpha/CompaqTru64platform. Therefore, we have to look for cost-effective solutions and finally a CompactPCI—Intelx86 platform with Linux operating system was chosen. A software porting has been done, taking intoaccount the differences between OS9 and Linux operating system in terms of Inter/Network ProcessesCommunications and I/O multi-ports serial driver. This paper describes the hardware/softwarearchitecture of the new MLC system, emphasizing the reliability and the low costs of the open sourcesolutions. Moreover, a huge amount of software packages available in open source environment willassure a less painful maintenance, and will open the way to further improvements of the systemitself.

关键词： compact PCI/linux control system tokamak

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Dominant pulse simulation of near fault ground motions

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Earthquake Engineering and Engineering Vibration 2013年第2期12卷 267-278页

作者： S.R. Hoseini Vaez M.K. Sharbatdar g. ghodrati Amiri H. Naderpour A. Kheyroddin Department of Civil Engineering Faculty of EngineeringUniversity of Qom Faculty of Civil Engineering Semnan University Center of Excellence for Fundamental Studies in Structural Engineering School of Civil EngineeringIran University of Science and Technology

In this study, a new mathematical model is developed composed of two parts, including harmonic and polynomial expressions for simulating the dominant velocity pulse of near fault ground motions. Based on a proposed velocity function, the corresponding expressions for the ground acceleration and displacement time histories are also derived. The proposed model is then fitted using some selected pulse-like near fault ground motions in the Next generation Attenuation （NgA） project library. The new model is not only simple in form but also simulates the long-period portion of actual velocity near fault records with a high level of precision. It is shown that the proposed model-based elastic response spectra are compatible with the near fault records in the neighborhood of the prevailing frequency of the pulse. The results indicate that the proposed model adequately simulates the components of the time histories. Finally, the energy of the proposed pulse was compared with the energy of the actual record to confirm the compatibility.

关键词： dominant pulse near fault ground motions forward directivity response spectra simulation

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Bulging in incremental sheet forming of cold bonded multi-layered Cu clad sheet: Influence of forming conditions and bending

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Transactions of Nonferrous Metals Society of China 2019年第1期29卷 112-122页

作者： Khalid A.AL-gHAMDI g.HUSSAIN Department of Industrial Engineering King Abdulaziz University Faculty of Mechanical Engineering GIK Institute of Engineering Sciences & Technology

Bulge is a defect that causes geometrical inaccuracy and premature failure in the innovative incremental sheet forming (ISF) process. This study has two-fold objectives:(1) knowing the bulging behavior of a Cu clad tri-layered steel sheet as a function of forming conditions, and (2) analyzing the bending effect on bulging in an attempt to identify the associated mechanism. A series of ISF tests and bending analysis are performed to realize these objectives. From the cause-effect analysis, it is found that bulge formation in the layered sheet is sensitive to forming conditions in a way that bulging can be minimized utilizing annealed material and performing ISF with larger tool diameter and step size. The bending under tension analysis reveals that the formation of bulge is an outgrowth of bending moment that the forming tool applies on the sheet during ISF. Furthermore, the magnitude of bending moment depending upon the forming conditions varies from 0.046 to 10.24 N·m/m and causes a corresponding change in the mean bulge height from 0.07 to 0.91 mm. The bending moment governs bulging in layered sheet through a linear law. These findings lead to a conclusion that the bulge defect can be overcome by controlling the bending moment and the formula proposed can be helpful in this regards.

关键词： incremental forming clad sheet bulge bending moment forming conditions

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土壤压实对土壤物理性质及小麦氮磷钾吸收的影响(英文)

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农业工程学报 2008年第1期24卷 74-79页

作者： g．R．Mari 姬长英周俊南京农业大学工学院南京210031 Department of Agricultural Engineering Sindh Agricultural University Tando-jam Pakistan

为了研究土壤压实对土壤物理性质以及小麦养分吸收情况的影响,在2006和2007年进行了两轮田间试验。试验中,先用旋耕机对田块进行旋耕,耕深10 cm,然后使用手扶式、轮式、履带式拖拉机在旋耕后的田块中通过1次(T1)、2次(T2)、4次(T3)以对... 详细信息

为了研究土壤压实对土壤物理性质以及小麦养分吸收情况的影响,在2006和2007年进行了两轮田间试验。试验中,先用旋耕机对田块进行旋耕,耕深10 cm,然后使用手扶式、轮式、履带式拖拉机在旋耕后的田块中通过1次(T1)、2次(T2)、4次(T3)以对土壤进行压实处理,对照组(T4)不作任何压实处理。压实处理后再次对土壤表层进行浅旋耕,耕深5 cm,耕后用播种机进行小麦播种,小麦品种为南京-601。试验结果发现,次表层土壤的压实处理显著影响次表层土壤的容重,孔隙度,小麦蛋白质含量以及植物中N、P、K的含量。除次表层的土壤容重在T3组中最大,T4组中最小外,其他参数值在T4组中最大,T3组中最小。并且,随着次表层土壤压实程度的增加,几乎所有的参数(土壤容重除外)都有所减少。不过,与第一年相比,参数值在第二年略有增加。总之,土壤压实严重破坏土壤结构,不利于小麦对养分的吸收。

关键词：小麦压实谷物蛋白质容重孔隙度 N/P/K 土壤

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EXTRAPOLATION AND A-POSTEriOri ERROR ESTIMATORS OF PETROV-gALERKIN METHODS FOR NON-LINEAR VOLTERRA INTegRO-DIFFERENTIAL EQUATIONS

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Journal of Computational Mathematics 2001年第4期19卷 407-422页

作者： Shu-hua Zhang (Department of Mathematical Sciences, University of Alberta, Edrmonton, Alberta, Canada T6g 2g1) Tao Lin (Department of Mathematics, Virginia Tech, Blacksburg VA 24061) Yan-ping Lin (Department of Mathematical Sciences, University of Alberta University of Alberta 加拿大 T6G 2G1 Virginia Tech 美国 VA 24061 University of Alberta 加拿大 T6G 2G6

In this paper we will show that the richardson extrapolation can be used to enhance the numerical solution generated by a Petrov-galerkin finite element method for the initial value problem for a nonlinear Volterra integro-differential equation. As by-products, we will also show that these enhanced approximations can be used to form a class of posteriori estimators for this Petrov-galerkin finite element method. Numerical examples are supplied to illustrate the theoretical results.

关键词： Volterra integro-differential equations Petrov-galerkin finite element methods Asymptotic expansions Interpolation post-processing A-posteriori error estimators.

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交联聚乙烯电缆绝缘中的双结构电树枝特性及其形态发展规律

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中国电机工程学报 2006年第3期26卷 79-85页

作者：郑晓泉 g Chen AE Davies 西安交通大学电力设备电气绝缘国家重点实验室陕西省西安市710049 英国南安普敦大学电子与计算机工程系

根据从电树枝动态生长过程中所拍摄的大量实验照片和生长特性数据,探讨了在XLPE电缆绝缘中的电树枝发展特征与材料聚集态结构的关系。研究表明,由于半结晶高聚物不均匀聚集态、不均匀结晶和残存应力的影响,会在XLPE电缆绝缘中生成枝状... 详细信息

根据从电树枝动态生长过程中所拍摄的大量实验照片和生长特性数据,探讨了在XLPE电缆绝缘中的电树枝发展特征与材料聚集态结构的关系。研究表明,由于半结晶高聚物不均匀聚集态、不均匀结晶和残存应力的影响,会在XLPE电缆绝缘中生成枝状、丛林状、藤枝状、松枝状和混合结构电树枝。并且在电树枝发展过程会呈现非常清晰的三个基本阶段,即引发阶段、滞长阶段和迅速发展阶段。引发阶段猛烈时生成迅速生长的纯枝状电树枝,引发阶段较弱或材料均匀时易导致丛林树状电树枝产生,发展于极不均匀区的电树枝多为鲜明的双结构;另外,引入一种新的参数,电树枝扩展系数来描述电树枝生长特性,并综合电树枝生长过程分形维数的变化规律和速度关系对产生这种实验现象的机理进行了分析。

关键词：交联聚乙烯电缆绝缘电树枝结构聚集态阶段发展规律

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