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Communications in Theoretical Physics 2020年第10期72卷 139-148页

作者： h A m Ali D m habashy Physics Department Faculty of EducationAin Shams UniversityRoxyCairo 11757Egypt

The impedance spectroscopy,electrical conductivity and electric modulus of bulk phenol red were measured,as a function of both frequency and *** neural networks(ANNs)were used for modeling its electrical *** two parts(real and imaginary)of its complex impedance(Z^*)were analyzed and the activation energy related to the electrical relaxation process was *** curves were plotted showing semicircles for the different *** AC electrical conductivity follows a power lawσac(ω)αω^η.The maximum barrier height Bm was derived for specific temperatures.A plausible mechanism for the AC conduction of bulk phenol red was deduced from the temperature reliance of the frequency *** dielectric data was analyzed using electric modulus as a *** addition,ANNs were used to model the impedance parts and the total electrical *** runs were tried,to obtain the best *** training and prediction results were compared to the equivalent experimental results,with a good match *** equation describing the experimental results was obtained math.m.tically,based on the use of *** outputs demonstrated that ANNs are an admirable tool for modeling experimental results.

关键词： phenol red impedance spectroscopy electric modulus neural network

Effect of partition coefficient on microsegregation during solidification of aluminium alloys

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International Journal of minerals,metallurgy and materials 2014年第10期21卷 980-989页

作者： m.h.Avazkonandeh-Gharavol m.haddad-Sabzevar h.Fredriksson Department of metallurgy and materials Engineering Faculty of Engineering Ferdowsi University of Mashhad Department of materials Science and Engineering School of Industrial Engineering and Management Royal Institute of Technology

In the modeling of microsegregation, the partition coefficient is usually calculated using data from the equilibrium phase diagrams. The aim of this study was to experimentally and theoretically analyze the partition coefficient in binary aluminum--copper alloys. The sam- ples were analyzed by differential thermal analysis （DTA）, which were melted and quenched from different temperatures during solidifica- tion. The mass fraction and composition of phases were measured by image processing and scanning electron microscopy （SEm） equipped with an energy-dispersive X-ray spectroscopy （EDS） unit. These data were used to calculate as the experimental partition coefficients with four different methods. The experimental and equilibrium partition coefficients were used to model the concentration profile in the primary phase. The modeling results show that the profiles calculated by the experimental partition coefficients are more consistent with the experi- mental profiles, compared to those calculated using the equilibrium partition coefficients.

关键词： aluminum copper alloys solidification partition coefficient microsegregation numerical modeling differential thermal analysis

Effect of substrate temperature on the morphological,structural,and optical properties of RF sputtered Ge(1-x)Snx films on Si substrate

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Chinese Physics B 2017年第5期26卷 313-318页

作者： h.m.hmodi m R hashim Nano-Optoelectronics Research Laboratory School of Physics Universiti Sains Malaysia 11800 USM Pulau Penang Malaysia Institute of Nano Optoelectronics Research and Technology (INOR) Universiti Sains Malaysia 11800 USM Pulau Penang Malaysia

In this study, Ge（1-x）Snx alloy films are co-sputtered on Si（100） substrates using RF magnetron sputtering at different substrate temperatures. Scanning electron micrographs, atomic force microscopy（AFm）, Raman spectroscopy, and x-ray photoemission spectroscopy（XPS） are conducted to investigate the effect of substrate temperature on the structural and optical properties of grown Ge Sn alloy films. AFm results show that RmS surface roughness of the films increases from 1.02 to 2.30 nm when raising the substrate temperature. This increase could be due to Sn surface segregation that occurs when raising the substrate temperature. Raman spectra exhibits the lowest FWhm value and highest phonon intensity for a film sputtered at 140℃. The spectra show that decreasing the deposition temperature to 140℃ improves the crystalline quality of the alloy films and increases nanocrystalline phase formation. The results of Raman spectra and XPS confirm Ge–Sn bond formation. The optoelectronic characteristics of fabricated metal-semiconductor-metal photodetectors on sputtered samples at room temperature（RT） and 140℃ are studied in the dark and under illumination. The sample sputtered at 140℃ performs better than the RT sputtered sample.

关键词： sputtering magnetron illumination crystalline raising roughness optoelectronic phonon segregation FWhm

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功能语体:两种对立倾向的相互作用

当代修辞学 1989年第3期 44-46页

作者： h.m.拉辛金娜刘大为

功能语体这一概念能够产生，仅仅是因为研究者开始把注意力转向各种类型话语篇章中不断重复出现的语言特征上，功能语体就此被确定为一个个稳定的系统，它们能够在特定的话语表现中对语言手段的选择进行调节。可是语言手段选择过程中的... 详细信息

功能语体这一概念能够产生，仅仅是因为研究者开始把注意力转向各种类型话语篇章中不断重复出现的语言特征上，功能语体就此被确定为一个个稳定的系统，它们能够在特定的话语表现中对语言手段的选择进行调节。可是语言手段选择过程中的稳定性只是功能语体的一个侧面，而另一个侧面，也就是稳定性中动态的、灵活的性质，却没有得到同样广泛的阐明。

关键词：功能语体相互作用对立倾向话语篇章语言手段稳定性语言特征选择过程

Electrical,thermal and electroch.m.cal properties of γ-ray-reduced graphene oxide

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International Journal of minerals,metallurgy and materials 2021年第10期28卷 1726-1734页

作者： m.m.Atta h.A.Ashry G.m.Nasr h.A.Abd El-Rehim Radiation Physics Department National Center for Radiation Research and Technology(NCRRT)Atomic Energy AuthorityCairo 11787Egypt Physics Department Faculty of ScienceCairo UniversityCairo 12613Egypt Radiation Ch.m.stry Department National Center for Radiation Research and Technology(NCRRT)Atomic Energy AuthorityCairo 11787Egypt

The properties of γ-ray-reduced graphene oxide samples(GRGOs)were compared with those of hydrazine hydrate-reduced graphene oxide(hRGO).Fourier transform infrared spectroscopy,X-ray diffractometry,Raman spectroscopy,Brunauer-Emmett-Teller surface area analysis,thermogravimetric analysis,electrometry,and cyclic voltammetry were carried out to verify the reduction process,structural changes,and defects of the samples,as well as to measure their thermal,electrical,and electroch.m.cal *** with γ-rays distorted the structure of GRGOs and generated massive defects through the extensive formation of new smaller sp^(2)-hybridized domains compared with those of *** thermal stability of GRGOs was higher than that of hRGO,indicating the highly efficient removal of thermally-labile oxygen species by γ-*** prepared at 80 kGy showed a pseudocapacitive behavior comparable with the electrical double-layer capacitance behavior of ***,the specific capacitance of GRGO was enhanced by nearly three times compared with that of *** results reflect the advantages of radiation reduction in energy storage applications.

关键词： graphene γ-ray electrical thermal electroch.m.cal

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玻璃熔窖用电熔耐火材料

玻璃熔窖用电熔耐火材料

1983年

作者： (苏)h.m.加尔吉娜

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高等学校教学用书材料力学下第1分册

高等学校教学用书材料力学下第1分册

Bending analysis of five-layer curved functionally graded sandwich panel in magnetic field:closed-form solution

1956年

作者： h.m.别辽耶夫于光瑜等译

来源：汇雅图书（南通市图书馆... 评论

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Applied math.m.tics and mechanics(English Edition) 2021年第2期42卷 251-274页

作者： m.ShABAN h.m.ZAhERI mechanical Engineering Department Bu-Ali Sina UniversityHamadan 3869-6517Iran

In this paper,an exact closed-form solution for a curved sandwich panel with two piezoelectric layers as actuator and sensor that are inserted in the top and bottom facings is *** core is made from functionally graded(FG)material that has heterogeneous power-law distribution through the radial *** is assumed that the core is subjected to a magnetic field whereas the core is covered by two insulated composite *** determine the exact solution,first characteristic equations are derived for different material types in a polar coordinate system,namely,magneto-elastic,elastic,and electro-elastic for the FG,orthotropic,and piezoelectric materials,*** displacement-based method is used instead of the stress-based method to derive a set of closed-form real-valued solutions for both real and complex *** on the elasticity theory,exact solutions for the governing equations are determined layer-by-layer that are considerably more accurate than typical simplified *** accuracy of the presented method is compared and validated with the available literature and the finite element *** effects of geometrical and material parameters such as FG index,angular span along with external conditions such as magnetic field,mechanical pressure,and electrical difference are investigated in detail through numerical examples.

关键词： five-layer sandwich panel piezoelectric material closed-form solution functionally graded(FG)material magnetic field

Nonlinear dynamical wave structures of Zoomeron equation for population models

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Chinese Physics B 2022年第6期31卷 235-240页

作者： Ahmet Bekir Emad h.m.Zahran Neighbourhood of Akcaglan Imarli StreetNumber:28/426030EskisehirTurkey Departments of math.m.tical and Physical Engineering Benha UniversityFaculty of EngineeringShubraEgypt

The nonlinear dynamical exact wave solutions to the non-fractional order and the time-fractional order of the biological population models are achieved for the first time in the framwork of the Paul-Painlevéapproach.m.thod(PPAm).When the variables appearing in the exact solutions take specific values,the solitary wave solutions will be easily *** realized results prove the efficiency of this technique.

关键词： (2+1)-dimensional non-fractional Zoomeron equation time-fractional biological population model Paul-Painlevéapproach.m.thod traveling wave solutions

EFFECT OF SnO_2 ADDITION ON ThE SERVICE LIFE AND ELECTROCh.m.CAL PROPERTIES OF Ti/IrO_2,+Ta_2O_5 ANODES IN PhENOLSULFONIC ACID SOLUTION

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Acta metallurgica Sinica(English Letters) 2000年第4期13卷 937-943页

作者： J.m. hu h.m. meng D.B. Sun S.J. Zhang J.X. Wu and D.J. Yang Beijing Corrosion and Protection Center, Open Laboratory of Corrosion, Erosion and Surface Technology, University of Science and Technology Beijing, Beijing 100083, China Beijing Univ of Science and Technology Beijing China

Service life of two different oxide anodes in phenolsulfonic acid (PSA) solution was investigated by accelerated electrolysis. The durability of Ti/IrO_2+Ta_2 O_5 anode increased by the addition of SnO_2 in the mixed oxides. The degradation mechanisms of Ti/IrO_2+ Ta_2 O_5 and Ti/IrO_2 +Ta_2 O_5 +SnO+2 anodes were different. It was shown from the observation of scanning electron microscopy (SEm) and the electroch.m.cal measurement that, the deactivation of Ti/IrO_2 + Ta_2 O_5 anode was due to the build-up of an organic film on surface. The growth of the covered film on surface was restricted by addition of SnO_2, which resulted in increasing of the service life of anodes. The over-potential for oxygen evolution on Ti/IrO_2 +Ta_2 O_5 electrode increased after doping SnO_2, and the intermediate products of PSA building-up on the surface was much.m.re rapidly oxidized. meanwhile, a certain part of the surface oxide deposit entered into the solution leading to loss of oxides, which resulted in degradation of Ti/IroO_2 + Ta_2 O_5 anode containing SnO_2 component.

关键词： metal oxide anode IrO_2 + Ta_2 O_5 IrO_2 + Ta_2 O_5 +SnO_2 phenolsulfonic acid degradation