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Fabrication of an r-Al_2Ti intermetallic matrix composite reinforced with α-Al_2O_3 ceramic by discontinuous mechanical milling for thermite reaction

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International Journal of Minerals,Metallurgy and Materials 2014年第10期21卷 1037-1043页

作者： A.Mosleh M.Ehteshamzadeh r.Taherzadeh Mousavian Department of Materials Science and Engineering Shahid Bahonar University of Kerman Department of Metallurgy Zanjan Branch Islamic Azad University

In this study, a powder mixture with an Al/TiO2 molar ratio of 10/3 was used to form an r-Al2Ti intermetallic matrix composite （IMC） reinforced with α-Al2O3 ceramic by a novel milling technique, called discontinuous mechanical milling （DMM） instead of milling and ignition of the produced thermite. The results of energy dispersive X-ray spectroscopy （EDX） and X-ray diffraction （XrD） of samples with varying milling time indicate that this fabrication process requires considerable mechanical energy. It is shown that Al2Ti-α-Al2O3 IMC with small grain size was produced by DMM after 15 h of ball milling. Peaks for γ-TLA1 as well as Al2Ti and Al2O3 are observed in XrD patterns after DMM followed by heat treatment. The microhardness of the DMM-treated composite produced after heat treatment was higher than Hv 700.

关键词： composite materials intermetallics alumina titanium aluminide ball milling thermite reaction process

Logarithmic Entropy Corrected Holographic Dark Energy with F(r, T ) Gravity

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Communications in Theoretical Physics 2015年第10期64卷 485-490页

作者： Ali r.Amani A.Samiee-Nouri Faculty of Sciences Department of Physics Ayatollah Amoli Branch Islamic Azad University Department of Physics Central Tehran Branch Islamic Azad University

In this paper, we consider F(r,T) gravity as a linear function of the curvature and torsion scalars and interact it with logarithmic entropy corrected holographic dark energy to evaluate cosmology solutions. The model is investigated by FrW metric, and then the energy density and the pressure of dark energy are calculated. Also we obtain equation of state(EoS) parameter of dark energy and plot it with respect to both variable of redshift and e-folding number. Finally, we describe the scenario in three status: early, late and future time by e-folding number.

关键词： equation of state parameter F(r T) gravity logarit

Swampland dS conjecture in mimetic f(r,T)gravity

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Communications in Theoretical Physics 2022年第8期74卷 101-115页

作者： S Noori Gashti J Sadeghi S Upadhyay M r Alipour Department of Physics Faculty of Basic SciencesUniversity of Mazandaran PO Box 47416-95447BabolsarIran Department of Physics K.L.S.CollegeNawadaBihar 805110India Department of Physics Magadh UniversityBodh GayaBihar 824234India Inter-University Centre for Astronomy and Astrophysics(IUCAA) PuneMaharashtra 411007India School of Physics Damghan UniversityDamghan ***Iran

In this paper,we study a theory of gravity called mimetic f(r,T)in the presence of swampland dS *** this purpose,we introduce several inflation solutions of the Hubble parameter H(N)from f(r,T)=r+δT gravity model,in which r is ricci scalar,and T denotes the trace of the energy–momentum ***,δand N are the free parameter and a number of e-fold,*** we calculate quantities such as potential,Lagrange multiplier,slow-roll,and some cosmological parameters such as nsand *** we challenge the mentioned inflationary model from the swampland dS *** discuss the stability of the model and investigate the compatibility or incompatibility of this inflationary scenario with the latest Planck observable data.

关键词： mimetic f(r,T)gravity Lagrange multiplier swampland conjecture

On the ruled surfaces in Minkowski 3-space r1^3

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第3期7卷 326-329页

作者： ■rENM■■ Alper Osman BALGET■r Handan ErGüT Mahmut Department of Mathematics Faculty of Arts and Sciences F■rat University Elaz■■ Turkey Department of Mathematics Faculty of Arts and Sciences F■rat University Elaz■■ TurkeyDepartment of Mathematics Faculty of Arts and Sciences F■rat University Elaz■■ Turkey

Izumiya and Takeuchi （2003） obtained some characterizations for ruled surfaces. Turgut and Haclsalihoglu （1998） defined timelike ruled surfaces and obtained some characterizations in timelike ruled surfaces. Choi （1995） and Jung and Pak （1996） studied ruled surfaces. This study uses the method in （lzumiya and Takeuchi, 2003） to investigate cylindrical helices and Bertrand curves as curves on timelike ruled surfaces in Minkowski 3-space r1^3. We have studied singularities of the rectifying developable （surface） of a timelike curve. We observed that the rectifying developable along a timelike curve a is non-singular if and only if a is a cylindrical helice. In this case the rectifying developable is a cylindrical surface.

关键词： Timelike ruled surfaces Bertrand curve Cylindrical helices

Exergy analysis of r1234ze（Z） as high temperature heat pump working fluid with multi-stage compression

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Frontiers in Energy 2017年第4期11卷 493-502页

作者： Bin HU Di WU L.W. WANG r.Z. WANG Institute of refrigeration and Cryogenics Shanghai Jiao Tong University Shanghai 200240 China

In this paper, the simulation approach and exergy analysis of multi-stage compression high tempera- ture heat pump （HTHP） systems with r1234ze（Z） working fluid are conducted. Both the single-stage and multi-stage compression cycles are analyzed to compare the system performance with 120℃ pressurized hot water supply based upon waste heat recovery. The exergy destruction ratios of each component for different stage compression systems are compared. The results show that the exergy loss ratios of the compressor are bigger than that of the evaporator and the condenser for the single-stage compres- sion system. The multi-stage compression system has better energy and exergy etticiencies with the increase of compression stage number. Compared with the single- stage compression system, the coefficient of performance （COP） improvements of the two-stage and three-stage compression system are 9.1% and 14.6%, respectively. When the waste heat source temperature is 60℃, the exergy efficiencies increase about 6.9% and 11.8% for the two-stage and three-stage compression system respec- tively.

关键词： multi-stage compression high temperatureheat pump heat recovery exergy destruction,r1234ze(Z) working fluid

ZnO nanorefrigerant in r152a refrigeration system for energy conservation and green environment

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Frontiers of Mechanical Engineering 2014年第1期9卷 75-80页

作者： D. SENDIL KUMAr r. ELANSEZHIAN Department of Mechanical Engineering Pondicherry EngineeringCollege Puducherry 605014 India

In this paper the reliability and performance of a vapour compression refrigeration system with ZnO nanoparticles in the working fluid was investigated experimentally. Nanorefrigerant was synthesized on the basis of the concept of the nanofluids, which was prepared by mixing ZnO nanoparticles with r152a refrigerant. The conventional refrigerant r134a has a global warming potential （GWP） of 1300 whereas r152a has a significant reduced value of GWP of 140 only. An experimental test rig is designed and fabricated indigenously in the laboratory to carry out the investigations. ZnO nanopar- ticles with refrigerant mixture were used in HFC r152a refrigeration system. The system performance with nanoparticles was then investigated. The concentration of nano ZnO ranges in the order of 0.1% v, 0.3% v and 0.5%v with particle size of 50nm and 150g of r152a was charged and tests were conducted. The compressor suction pressure, discharge pressure and evaporator temperature were measured. The results indicated that ZnO nanore- frigerant works normally and safely in the system. The ZnO nanoparticle concentration is an important factor considered for heat transfer enhancement in the refrigera- tion system. The performance of the system was significantly improved with 21% less energy consumption when 0.5%v ZnO-r152a refrigerant. Both the suction pressure and discharge pressure were lowered by 10.5% when nanorefrigerant was used. The evaporator tempera- ture was reduced by 6% with the use of nanorefrigerant. Hence ZnO nanoparticles could be used in refrigeration system to considerably reduce energy consumption. The usage of r 152a with zero ozone depleting potential （ODP） and very less GWP and thus provides a green and clean environment. The complete experimental results and their analysis are reported in the main paper.

关键词： ZnO nanorefrigerant reduced GWP COP,pressure ratio green energy

Dirac r-matrix calculations of photoionization cross sections of Ni Ⅻ and atomic structure data of Ni 

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Chinese Physics B 2017年第2期26卷 127-140页

作者： r T Nazirt M A Bari M Bilal S Sardar M H Nasim M Salahuddin Department of Physics and Applied Mathematics Pakistan Institute of Engineering and Applied Sciences Islamabad 45650 Pakista

We performed r-matrix calculations for photoionization cross sections of the two ground state configuration 3s^23p^5（~2P_（3/2,1/2）~o） levels and 12 excited states of Ni Ⅻ using relativistic Dirac Atomic r-matrix Codes（DArC） across the photon energy range between the ionizations thresholds of the corresponding states and well above the thresholds of the last level of the Ni XIII target ion. Generally, a good agreement is obtained between our results and the earlier theoretical photoionization cross sections. Moreover, we have used two independent fully relativistic GrASP and FAC codes to calculate fine-structure energy levels, wavelengths, oscillator strengths, transitions rates among the lowest 48 levels belonging to the configuration（3s^23p^4, 3s3p^5, 3p^6, 3s^23p^33d） in Ni XIII. Additionally, radiative lifetimes of all the excited states of Ni XIII are presented. Our results of the atomic structure of Ni XIII show good agreement with other theoretical and experimental results available in the literature. A good agreement is found between our calculated lifetimes and the experimental *** present results are useful for plasma diagnostic of fusion and astrophysical plasmas.

关键词： photoionization cross sections energy levels wavelengths lifetimes

FLrW cosmology in metric-affine F(r,Q)gravity

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Chinese Physics C 2024年第12期48卷 158-172页

作者： Dinesh Chandra Maurya K.Yesmakhanova r.Myrzakulov G.Nugmanova Centre for Cosmology Astrophysics and Space ScienceGLA UniversityMathura-281406Uttar PradeshIndia ratbay Myrzakulov Eurasian International Centre for Theoretical Physics Nur-Sultan010009Kazakhstan

We investigated some Friedmann-Lemaître-robertson-Walker(FLrW)cosmological models in the context of metric-affine F(r,Q)gravity,as proposed in[arXiv:1205.5266v6].Here,r and Q are the curvature and nonmetricity scalars using non-special connections,*** obtained the modified field equations using a flat FLrW *** then found a connection between the Hubble constant H_(0),density parameter Ω_(m0),and other model parameters in two different situations involving scalars u and ***,we used new observational datasets,such as the cosmic chronometer(CC)Hubble and Pantheon SNe Ia datasets,to determine the optimal model parameter values through a Markov chain Monte Carlo(MCMC)*** these best-fit values of the model parameters,we discussed the results and behavior of the derived ***,we discussed the Akaike information criterion(AIC)and Bayesian information criterion(BIC)for the derived models in the context of the Lambda cold dark matter(ΛCDM).We found that the geometrical sector dark equation of state parameter ω_(de)behaves just like a dark energy *** also found that both models are transit phase ***-Ⅰ approaches the ΛCDM model in the late-time universe,whereas Model-Ⅱ approaches quintessence scenarios.

关键词： metric-affine F(r,Q)gravity FLrW flat universe FLrW cosmology transit phase expansion observational constraints

Emotion Exploration in Autistic Children as an Early Biomarker through r-CNN

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Intelligent Automation & Soft Computing 2023年第1期35卷 595-607页

作者： S.P.Abirami G.Kousalya r.Karthick Coimbatore Institute of Technology CoimbatoreIndia Steps rehabilitation Center(I) Steps GroupsCoimbatoreIndia

Autism Spectrum Disorder(ASD)is found to be a major concern among various occupational *** foremost challenge of this neurodeve-lopmental disorder lies in the fact of analyzing and exploring various symptoms of the children at their early stage of *** early identification could prop up the therapists and clinicians to provide proper assistive support to make the children lead an independent *** expressions and emotions perceived by the children could contribute to such early intervention of *** this regard,the paper implements in identifying basic facial expression and exploring their emotions upon a time-variant *** emotions are analyzed by incorporating the facial expression identified through Convolution Neural Network(CNN)using 68 landmark points plotted on the frontal face with a prediction network formed by recurring Neural Network(rNN)known as the rCNN based Facial Expression recommendation(FEr)*** paper adopts recurring Convolution Neural Network(r-CNN)to take the advantage of increased accuracy and performance with decreased time complexity in predicting emotion as textual network *** papers prove better accuracy in identifying the emotion in autistic children when compared over simple machine learning models built for such identifications contributing to autistic society.

关键词： Autism spectrum disorder facial expression emotion CNN rNN