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Acta Metallurgica Sinica(English Letters) 2013年第6期26卷 699-706页

作者： Muhammad Arslan Riaz Muhammad Arshad Mahmood rashad rasheed Department of Applied Physics Federal Urdu University of ArtsSciences and Technology National Institute of Lasers and Optronics

Thin films of Zn1-xCuxSe （x= 0.00, 0.05, 0.10, 0.15, 0.20） were grown on glass substrates by closed space sublimation technique. The deposited films were annealed at 200 ~C and 400 ~C in air for 1 h. The annealed samples have been investigated through Rutherford backscattering spectroscopy （RBS）, X-ray diffraction （XRD）, spectroscopic ellipsometer, spectrophotometer and Raman spectroscopy. Through RBS, the composition of the films was calculated and compared with the initial concentration. Structural characteriza- tion including crystal structure, crystal orientation, lattice parameter, grain size, strain and dislocation density were carried out using XRD data. From XRD spectra it was revealed that the as-deposited and annealed films were polycrystalline in nature with zinc-blende structure. However, the crystallinity and the grain size were improved with the increase of annealing temperature. According to Raman spectroscopy, it was observed that as deposited and annealed samples have the same characteristic vibrational modes of ZnSe at low and high frequency optical phonon modes while another mode was observed for 400 ℃ annealed samples at 745 cm-1. Spectroscopic ellipsometer has been used to found annealing effect on the optical properties of ZnSe. The band gap energy has been determined using transmission spectra. It was found that the band gap energy of the film increased with the increase of annealing temperature.

关键词： Closed space sublimation Annealing effect Structural Transmission Band gap Spectroscopic ellipsometer Raman spectroscopy

Understanding the low temperature electrochemistry of magnesium-lithium hybrid ion battery in all-phenyl-complex solutions

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Journal of Energy Chemistry 2021年第5期30卷 383-390页

作者： Muhammad rashad Muhammad Asif School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003JiangsuChina Bernal Institute Department of Chemical SciencesUniversity of LimerickLimerick V94 T9PXIreland

Magnesium-lithium hybrid ion batteries have emerged as a new class of energy storage systems owing to dendrite free cycling of magnesium anode and possibility of practice of numerous conventional lithium *** present work,we used hybrid ion strategy to analyze the performance of lithium titanate based lithium cathode,magnesium metal anode,and all-phenyl complex(APC)electrolytes at different temperatures(25℃,10℃,0℃,-10℃,and-20℃).The hybrid ion battery exhibited excellent rate performance(228 m Ah g^(-1)/20 m A g^(-1) and 163 mAh g^(-1)/1000 mA g^(-1))with stable voltage plateaus at 0.90 and 0.75 V,which corresponds to specific energy of 178 Wh kg^(-1) at room temperature(25℃).Experimental results revealed that APC-THF solutions have strong potential to suppress the freezing of electrolyte solutions owing to low boiling point of *** low temperature electrochemical testing revealed the reversible capacities of 213.4,165.5,143.8,133.2 and 78.56 mAh g^(-1) at 25,10,0,-10,and-20℃,***,ex-situ XRD,SEM,and EIS tests were carried out to understand the reaction kinetics of both Mg2+and Li+ions inside the lithium titanate *** hope this work will shed light on low temperature prospective of electrochemical devices for use in cold environments.

关键词： Mg ion battery Mg-Li hybrid ion batteries Electrochemical properties Low temperature Energy storage

Multivariate form of Hermite sampling series

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 253-265页

作者： rashad M.Asharabi Department of Mathematics College of Arts and SciencesNajran UniversityNajranSaudi Arabia

In this paper,we establish a new multivariate Hermite sampling series involving samples from the function itself and its mixed and non-mixed partial derivatives of arbitrary *** multivariate form of Hermite sampling will be valid for some classes of multivariate entire functions,satisfying certain growth *** will show that many known results included in Commun Korean Math Soc,2002,17:731-740,Turk J Math,2017,41:387-403 and Filomat,2020,34:3339-3347 are special cases of our ***,we estimate the truncation error of this sampling based on localized sampling without decay *** examples are also presented.

关键词： multidimensional sampling series sampling with partial derivatives contour integral truncation error

tRNA cleavage: a new insight

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Neural Regeneration Research 2020年第1期15卷 47-52页

作者： Sherif rashad Kuniyasu Niizuma Teiji Tominaga Department of Neurosurgery Tohoku University Graduate School of MedicineSendaiJapan Department of Neurosurgical Engineering and Translational Neuroscience Tohoku University Graduate School of MedicineSendaiJapan Department of Neurosurgical Engineering and Translational Neuroscience Graduate School of Biomedical EngineeringTohoku UniversitySendaiJapan

Over the past decades,tRNA was found to be a rich hub of RNA modifications such as 1-methyladenosine and 5-methycytosine modifications and others,holding more than half of all modifications occurring in RNA ***,tRNA was discovered to be a source of various small noncoding RNA species,such as the stress induced angiogenin cleaved tRNA halves(tiRNA)or the miRNA like tRNA derived *** cleavage under stress was fist discovered in bacteria and later was found to be conserved across different species,including *** cellular stress conditions,tRNA undergoes conformational changes and angiogenin cleaves it into 3′and 5′halves.5′tiRNA halves were shown to repress protein *** cleavage is thought of to be a cytoprotective mechanism by which cells evade apoptosis,however some data hints to the opposite;that tiRNA are cytotoxic or at least related to apoptosis *** cleavage also was shown to be affected by tRNA modifications via different enzymes in the cytosol and *** this review,we will highlight the biology of tRNA cleavage,show the evidence of it being cytoprotective or a marker of cell death and shed a light on its role in disease models and human diseases as well as possible future directions in this field of RNA research.

关键词： angiogenin apoptosis cell stress RNA modification stress granules stroke tiRNA translation repression tRNA tRNA cleavage

Activation Functions Effect on Fractal Coding Using Neural Networks

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Intelligent Automation & Soft Computing 2023年第4期36卷 957-965页

作者： rashad A.Al-Jawfi Department of Mathematics Faculty of Sciences and ArtsNajran UniversityKSA

Activation functions play an essential role in converting the output of the artiﬁcial neural network into nonlinear results,since without this nonlinearity,the results of the network will be less *** is the mission of all nonlinear functions,except for *** activation function must be dif-ferentiable for backpropagation *** study’s objective is to determine the best activation functions for the approximation of each fractal *** results have been attained using Matlab and Visual Basic programs,which indi-cate that the bounded function is more helpful than other *** non-lin-earity of the activation function is important when using neural networks for coding fractal images because the coefﬁcients of the Iterated Function System are different according to the different types of *** most commonly cho-sen activation function is the sigmoidal function,which produces a positive *** functions,such as tansh or arctan,whose values can be positive or negative depending on the network input,tend to train neural networks *** coding speed of the fractal image is different depending on the appropriate activation function chosen for each fractal *** this paper,we have provided the appro-priate activation functions for each type of system of iterated functions that help the network to identify the transactions of the system.

关键词： Activation function fractal coding iterated function system

Cost-effective integrated strategy for the fabrication of hard-magnet barium hexaferrite powders from low-grade barite ore

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International Journal of Minerals,Metallurgy and Materials 2016年第9期23卷 991-1000页

作者： M.M.S.Sanad M.M.rashad Central Metallurgical R & D Institute

Ultrafine barium hexaferrite（BaFe12O19） powders were synthesized from the metallurgical extracts of low-grade Egyptian barite ore via a co-precipitation route. Hydrometallurgical treatment of barite ore was systematically studied to achieve the maximum dissolution efficiency of Fe（～99.7%） under the optimum conditions. The hexaferrite precursors were obtained by the co-precipitation of BaS produced by the reduction of barite ore with carbon at 1273 K and then dissolved in diluted HCl and FeCl3 solution at pH 10 using NaOH as a base; the product was then annealed at 1273 K in an open atmosphere. The effect of Fe^3＋/Ba^2＋ molar ratio and the addition of hydrogen peroxide（H2O2） on the phase structure, crystallite size, morphology, and magnetic properties were investigated by X-ray diffraction, scanning electron microscopy, and vibrating sample magnetometry. Single-phase BaFe（12）O（19） powder was obtained at an Fe^3＋/Ba^2＋ molar ratio of 8.00. The formed powders exhibited a hexagonal platelet-like structure. Good maximum magnetization（48.3 A×m^2×kg^–1） was achieved in the material prepared at an Fe^3＋/Ba^2＋ molar ratio of 8.0 in the presence of 5% H2O2 as an oxidizer and at 1273 K because of the formation of a uniform, hexagonal-shaped structure.

关键词： chemical process barite ore treatment characterization magnetic properties ferrites

Generalized Marshall Olkin Inverse Lindley Distribution with Applications

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Computers, Materials & Continua 2020年第9期64卷 1505-1526页

作者： rashad Bantan Amal S.Hassan Mahmoud Elsehetry Deanship of Scientific Research King AbdulAziz UniversityJeddah21589Saudi Arabia Faculty of Graduate Studies for Statistical Research Cairo UniversityCairo11865Egypt Deanship of Information Technology King AbdulAziz UniversityJeddah21589Saudi Arabia

In this article,a new generalization of the inverse Lindley distribution is introduced based on Marshall-Olkin family of *** call the new distribution,the generalized Marshall-Olkin inverse Lindley distribution which offers more flexibility for modeling lifetime *** new distribution includes the inverse Lindley and the Marshall-Olkin inverse Lindley as special *** properties of the generalized Marshall-Olkin inverse Lindley distribution are discussed and investigated including,quantile function,ordinary moments,incomplete moments,moments of residual and stochastic *** likelihood method of estimation is considered under complete,Type-I censoring and Type-II *** likelihood estimators as well as approximate confidence intervals of the population parameters are discussed.A comprehensive simulation study is done to assess the performance of estimates based on their biases and mean square *** notability of the generalized Marshall-Olkin inverse Lindley model is clarified by means of two real data *** results showed the fact that the generalized Marshall-Olkin inverse Lindley model can produce better fits than power Lindley,extended Lindley,alpha power transmuted Lindley,alpha power extended exponential and Lindley distributions.

关键词： Generalized Marshal-Olkin family inverse Lindley distribution maximum likelihood estimation

Zubair Lomax Distribution:Properties and Estimation Based on Ranked Set Sampling

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Computers, Materials & Continua 2020年第12期65卷 2169-2187页

In this article,we offer a new adapted model with three parameters,called Zubair Lomax *** new model can be very useful in analyzing and modeling real data and provides better fits than some others new *** properties of the Zubair Lomax model are determined by moments,probability weighted moments,Renyi entropy,quantile function and stochastic ordering,among *** likelihood method is used to estimate the population parameters,owing to simple random sample and ranked set sampling *** behavior of the maximum likelihood estimates for the model parameters is studied using Monte Carlo *** measures including biases,mean square errors and relative efficiencies are used to compare *** the simulation study,we observe that the estimates based on ranked set sampling are more efficient compared to the estimates based on simple random *** importance and flexibility of Zubair Lomax are validated empirically in modeling two types of lifetime data.

关键词： Lomax distribution Zubair-g family moments maximum likelihood estimation ranked set sampling

Double sampling derivatives and truncation error estimates

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Applied Mathematics(A Journal of Chinese Universities) 2018年第2期33卷 209-224页

作者： rashad M.Asharabi Aisha M.Al-Hayzea Department of Mathematics College of Arts and Sciences Najran University

This paper investigates double sampling series derivatives for bivariate functions defined on R2 that are in the Bernstein space. For this sampling series, we estimate some of the pointwise and uniform bounds when the function satisfies some decay conditions. The truncated series of this formula allow us to approximate any order of partial derivatives for function from Bernstein space using only a finite number of samples from the function itself. This sampling formula will be useful in the approximation theory and its applications, especially after having the truncation error well-established. Examples with tables and figures are given at the end of the paper to illustrate the advantages of this formula.

关键词： double sampling series truncation error bounds convergence rate

Enhanced ductility of Mg–3Al–1Zn alloy reinforced with short length multiwalled carbon nanotubes using a powder metallurgy method

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Progress in Natural Science:Materials International 2015年第4期25卷 276-281页

作者： Muhammad rashad Fusheng Pan Muhammad Asif Li Li College of Materials Science and Engineering Chongqing University National Engineering Research Center for Magnesium Alloys Chongqing University Chongqing Academy of Science and Technology School of Materials Science and Engineering Dalian University of Technology

Mg–3Al–1Zn–CNTs composites, with different weight fractions(0.25–1.0 wt%) of carbon nanotubes(CNTs) were successfully fabricated via a powder metallurgy method. The processing parameters were adopted in such a way to have uniform dispersion of short length CNTs without any damage, as well as re fi ned and dissolved β phases structures throughout the composite matrix. The composite exhibited impressive increase in microhardness(about+23%) and tensile failure strain value(about+98%) without signi fi cant compromise in tensile strength, compared to the un-reinforced Mg–3Al–1Zn alloy. The synthesized composites can be used in automotive and aerospace industries due to their low density and high speci fic strength.

关键词： Metal matrix composites Mechanical properties Powder processing