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Krein regularization of λφ~3 theory

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Chinese Physics C 2015年第6期39卷 30-33页

作者： b.Forghan Department of Physics Islamic Azad University

In this paper, the one-loop self energy of λφ3 theory is calculated by using Krein regularization in four and six dimensions and the result, which is finite, is compared with the conventional result of λφ3 theory in Hilbert space. The self energy is calculated in the one-loop approximation and the result is automatically regularized as a result of “Krein Regularization”.

关键词： regularization theory automatically dimensions quantization appearance applying rotation similarity remove

High-risk prostate cancer： is androgen deprivation monotherapy still appropriate？

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Asian Journal of Andrology 2012年第3期14卷 419-420,I0006页

作者： Vahakn b Shahinian Department of Internal Medicine University of MichiganAnn Arbor MI 48109-2029 USA

The optimal management of high-risk prostate cancer, defined by tumor stage T3a or higher, a Gleason score ot 8-10 or a prostate-specific antigen level 〉20 ng m1-1, is unclear, and continues to be a source of substantial controversy.1 Though now much less common with the widespread adoption of prostate-specific antigen screening, it remains important as a cause of prostate cancer death. In large clinical trials,

关键词： High-risk androgen

Energy Savings Estimation of a Distribution System in Presence of Intelligent Volt-VAr Control based on IEEE Std.1547-2018

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CSEE Journal of Power and Energy Systems 2022年第5期8卷 1477-1486页

作者： Saran Satsangi G.b.Kumbhar Department of Electrical Engineering Indian Institute of Technology RoorkeeRoorkeeUttarakhandIndia

In the present scenario,many solar photovoltaic(SPV)systems have been installed in the distribution network,most of them are operating at the unity power factor,which does not provide any reactive power *** future distribution grids,there will be significant advances in operating strategies of SPV systems with the introduction of smart inverter *** new IEEE Std.1547-2018 incorporates dynamic Volt/VAr control(VVC)for smart *** smart inverters can inject or absorb reactive power and maintain voltages at points of common coupling(PCCs)based on local voltage *** multiple inverter-interfaced SPV systems connected to the grid,it becomes a necessary task to develop local,distributed or hybrid VVC algorithms for maximization of energy *** paper aims to estimate substation energy savings through centralized and decentralized control of inverters of SPV system alongside various VVC *** strategies of each SPV inverter have been accomplished in compliance with IEEE ***-series simulations are carried out on the modified IEEE-123 node test *** utilizing smart inverters in traditional SPV systems,considerable energy savings can be *** savings can be further increased by incorporating optimal intelligent VVC characteristics(IVVCC).Results show that just by allowing smart inverters on a predefined IVVCC(as per IEEE Std.1547-2018),a reduction of 11.69%in reactive demand and 5.63%in active demand have been acquired when compared with a conventional SPV *** energy demand is additionally reduced to 48.42%by considering centralized control of VVC devices alongside optimal IVVCC.

关键词： Conservation voltage reduction IEEE Std.1547-2018 smart inverter functions solar photovoltaic system Volt/VAr control Volt/VAr optimization

Processing and characterization of the microstructure and mechanical properties of Al6061–Tib_(2) composite

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International Journal of Minerals,Metallurgy and Materials 2021年第6期28卷 1080-1089页

作者： Y.Pazhuhanfar b.Eghbali Faculty of Materials Science and Engineering Sahand University of TechnologyTabrizIran

In the present research,aluminum metal matrix composites were processed by the stir casting *** effects of Tib2 reinforcement particles,severe plastic deformation through accumulative roll bonding(ARb),and aging treatment on the microstructural characteristics and mechanical properties were also *** tensile tests and microhardness measurements were conducted,and the microstructural characteristics were ***,the important problems associated with cast samples,including nonuniformity of the reinforcement particles and high porosity content,were solved through the ARb *** the initial stage,particle-free zones,as well as particle clusters,were observed on the microstructure of the ***,after the ARb process,fracturing phenomena occurred in brittle ceramic particles,followed by breaking down of the fragments into fine particles as the number of rolling cycles ***,composites with a uniform distribution of particles were ***,the tensile strength and microhardness of the ARb-processed composites increased with the increase in the reinforcement mass ***,their ductility exhibited a different *** post-deformation aging treatment(T6),the mechanical properties of composites were improved because of the formation of fine Mg2Si precipitates.

关键词： stir casting accumulative roll bonding aging treatment mechanical properties microstructural characteristics Tib2 ceramic particle

A review of research on spontaneous combustion 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 liable for the self-heating and spontaneous combustion of coal. This phenomenon has imposed severe problems in coal related industries. Attempts to understand this phenomenon by 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 by temperature, oxidation history of coal,coal properties, particle size distribution of the coal, etc. The current understanding of the phenomenon of self-heating and spontaneous combustion of coal is discussed along with the different experimental and numerical models established to predict self-heating characteristics of coal. This paper focuses on the global position of the study carried out by academics, research institutes and industries on spontaneous combustion of coal and coal mine fires. Within this framework, the generally used spontaneous combustion techniques to predict the spontaneous combustion liability of coal were evaluated. These techniques are well-known in their usage, but no specific method has become a standard to predict the spontaneous combustion liability. Further study is still needed to indicate a number of impending issues and to obtain a more complete understanding on the phenomenon.

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

Intermetallic growth behavior during post deformation annealing in multilayer Ti/Al/Nb composite interfaces

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International Journal of Minerals,Metallurgy and Materials 2022年第8期29卷 1608-1617页

作者： R.Jafari b.Eghbali Department of Materials Engineering Faculty of EngineeringUrmia UniversityP.O.Box 57561-165UrmiaIran Faculty of Materials Engineering Sahand University of TechnologyP.O.Box 51335-1996TabrizIran

The tri-metal Ti-Al-Nb composites were processed through three procedures:hot pressing,rolling,and hot pressing,followed by subsequent *** fabricated composites were then subjected to annealing at 600,625,and 650℃ temperatures at different *** observation at the interfaces reveals that the increase in plastic deformation strain significantly affects TiAl_(3) intermetallic layers’evolution and accelerates the layers’*** the contrary,the amount of applied strain does not significantly affect the evolution of the NbAl_(3) intermetallic layer *** was also found that Al and Ti atoms’diffusion has occurred throughout the TiAl_(3) layer,but only Al atoms diffuse through the NbAl_(3) *** slow growth rate of the NbAl_(3) intermetallic layer is due to the lack of diffusion of Nb atoms and the high activation energy of Al atoms’reaction with Nb atoms.

关键词： intermetallic compounds diffusion Ti/Al/Nb composite deformation annealing

Pseudospin symmetric solutions of the Dirac equation with the modified Rosen-Morse potential using Nikiforov-Uvarov method and supersymmetric quantum mechanics approach

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Chinese Physics b 2022年第5期31卷 107-112页

作者： Wen-Li Chen I b Okon School of Intelligent Science and Information Engineering Xi’an Peihua UniversityXi’an 710125China Theoretical Physics Group Department of PhysicsUniversity of UyoNigeria

Employing the Pekeris-type approximation to deal with the pseudo-centrifugal term,we analytically study the pseudospin symmetry of a Dirac nucleon subjected to equal scalar and vector modified Rosen-Morse potential including the spin-orbit coupling term by using the Nikiforov-Uvarov method and supersymmetric quantum mechanics *** complex eigenvalue equation and the total normalized wave functions expressed in terms of Jacobi polynomial with arbitrary spin-orbit coupling quantum number k are presented under the condition of pseudospin *** eigenvalue equations for both methods reproduce the same result to affirm the mathematical accuracy of analytical *** numerical solutions obtained for different adjustable parameters produce degeneracies for some quantum number.

关键词： Dirac equation modified Rosen-Morse potential Nikiforov-Uvarov method supersymmetric quantum mechanics approach

Nonlinear dynamics and performance analysis of modified snap-through vibration energy harvester with time-varying potential function

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Applied Mathematics and Mechanics(English Edition) 2022年第2期43卷 185-202页

作者： K.DEVARAJAN b.SANTHOSH Department of Mechanical Engineering Amrita School of EngineeringAmrita Vishwa VidyapeethamCoimbatore641112India

Vibration energy harvesting has emerged as a promising method to harvest energy for small-scale *** the performance of a vibration energy harvester(VEH)incorporating nonlinear techniques,for example,the snap-through VEH with geometric non-linearity,has gained attention in recent years.A conventional snap-through VEH is a bi-stable system with a time-invariant potential function,which was investigated extensively in the *** this work,a modified snap-through VEH with a time-varying potential function subject to harmonic and random base excitations is *** snap-through VEHs,such as the one considered in this study,are used in wave energy ***,the studies on their dynamics and energy harvesting under harmonic and random excitations are *** dynamics of the modified snap-through VEH is represented by a system of differential algebraic equations(DAEs),and the numerical schemes are proposed for its *** a harmonic excitation,the system exhibits periodic and chaotic motions,and the energy harvesting is superior compared with the conventional *** dynamics under a random excitation is investigated by the moment differential method and the numerical scheme based on the modified Euler-Maruyama *** Fokker-Planck equation representing the dynamics is derived,and the marginal and joint probability density functions(PDFs)are obtained by the Monte Carlo *** study shows that the modified snap-through oscillator based VEH performs better under both harmonic and random *** dynamics of the system under stochastic resonance(SR)is investigated,and performance enhancement is *** results from this study will help in the development of adaptive VEH techniques in the future.

关键词： snap-through vibration energy harvester(VEH) time-varying potential function bifurcation probability density function(PDF) Fokker-Planck equation

Characterization and corrosion studies of ternary Zn–Ni–Sn alloys

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International Journal of Minerals,Metallurgy and Materials 2020年第1期27卷 74-82页

作者： Reyhan Solmaz b.Deniz Karahan Department of Metallurgical and Materials Engineering Istanbul Technical UniversityMaslakIstanbul 34469Turkey School of Engineering and Natural Sciences Istanbul Medipol UniversityBeykozIstanbul 34810Turkey

Nine distinct zinc-nickel-tin films with different compositions have been galvanostatically electrodeposited. The films have been characterized by scanning electron microscopy(SEM) and energy dispersive spectrometry(EDS). Their corrosion potentials and densities have been estimated using Tafel extrapolation. Next, the electrochemical behaviors of the films(deposited through the electrolytes containing 0, 6, 8, and10 g/L SnCl2?6H2O) have been examined based on cyclic voltammetry(CV) measurements. Further, these films have been immersed in 3.5 wt%Na Cl solution for 1 h, 1 d, 7 d, 14 d, 28 d, and 42 d followed by application of Tafel extrapolation and electrochemical impedance spectroscopy(EIS) tests on each aged sample. Finally, to analyze the morphologies and the compositions of the oxide films covering the surfaces of the 42-d aged films, FT-IR and SEM analyses have been performed. The results indicated that the Zn–Ni–Sn film produced through the bath including 6g/L SnCl2?6H2 O exhibits superior corrosion resistance because of the high Ni content in the presence of Sn that promotes the barrier protection capability of the deposit.

关键词： ternary alloys corrosion electro galvanizing anomalous deposition Tafel