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Effect of Co substitution on the structural,electrical,and magnetic properties of Bi_(0.9)La_(0.1)FeO_3 by sol-gel synthesis

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international Journal of Minerals,Metallurgy and Materials 2013年第2期20卷 166-171页

作者： Ghulam Ali Saadat A.Siddiqi shahid M.Ramay shahid Atiq Murtaza Saleem Centre of Excellence in Solid State Physics University of the Punjab interdisciplinary Research Centre in Biomedical Materials COMSATS Institute of Information Technology Chemical Engineering Department College of EngineeringKing Saud University

Cobalt （Co）-doped ***3 multiferroics were synthesized by a sol-gel method based on the auto- combustion technique. As-synthesized powder was examined using various characterization techniques to explore the effect of Co substitution on the properties of Bi0.9La0.1FeO3. X-ray diffraction reveals that Co-doped Bi0.9La0.1FeO3 preserves the perovskite-type rhombohedral structure of BiFeO3, and the composition without Co preserves the original structure of the phase; however, a second-phase Bi2Fe409 has been identified in all other compositions. Surface morphological studies were performed by scanning electron microscopy. Temperature-dependent resistivity of the samples reveals the characteristic insulating behavior of the multiferroic material. The resistivity is found to decrease with the increase both in temperature and Co content. Room temperature frequency-dependent dielectric measurements were also reported. Magnetic measurements show the enhancement in magnetization with the increase in Co content.

关键词： multiferroics cobalt doping microstructure electric properties magnetic properties sol-gel process

Accretion onto Charged Black Holes in Einstein and Massive Theories of Gravity

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Communications in Theoretical Physics 2019年第6期71卷 702-710页

作者： Abdul Jawad shahid Chaudhary Department of Mathematics COMSATS UniversityIslamabadLahore Campus-54000Pakistan Department of Mathematics Sharif College of Engineering and TechnologyLahore-54000Pakistan

The accretion process is being investigated onto some important black holes such as Born-infeld-AdS black hole, non-linear charged black hole solution in AdS space-time and Einstein-Yang-Mills massive gravity in the presence of Born-infeld nonlinear electrodynamics. We find out the relations of radial velocity, energy density and change of mass for mention black holes and analyze their behavior graphically for different values of equation of state parameters ω.We also examine the relations for critical speed for these black holes. it is observed that for different state parameters different fluids exhibit different evolutions in black holes backgrounds. The energy density of some fluids is negative or positive near the black hole while other fluids become cause to increase or decrease in black hole mass.

关键词： accretion black holes Einstein gravity massive gravity

Generalized Coherent States for Position-Dependent Effective Mass Systems

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Communications in Theoretical Physics 2016年第12期65卷 615-620页

作者： Naila Amir shahid iqbal School of Electrical Engineering and Computer Sciences National University of Sciences and Technology School of Natural Sciences National University of Sciences and Technology

A generalized scheme for the construction of coherent states in the context of position-dependent effective mass systems has been presented. This formalism is based on the ladder operators and associated algebra of the system which are obtained using the concepts of supersymmetric quantum mechanics and the property of shape invariance. in order to exemplify the general results and to analyze the properties of the coherent states, several examples have been considered.

关键词： generalized coherent states supersymmetric quantum mechanics shape invariance ladder operators position-dependent effective mass systems non-linear oscillators Mandel parameter subPoissonian statistics

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工时定额动态参数建模及可视化研究

系统仿真学报 2008年第S1期20卷 330-333页

作者：陆远 shahid ikramullah butt 南昌大学机电学院南昌中国330031 制造工程学院国立科技大学

工时定额数据获取的快速基于动态参数的工时定额计算方法。对影响工时定额计算结果的诸多参数进行分析,根据参数的性和准确性影响着制造成本和作业计划。传统计算方法效率低、准确性差,为解决这一问题提出了信息表达方式进行分类,建立... 详细信息

工时定额数据获取的快速基于动态参数的工时定额计算方法。对影响工时定额计算结果的诸多参数进行分析,根据参数的性和准确性影响着制造成本和作业计划。传统计算方法效率低、准确性差,为解决这一问题提出了信息表达方式进行分类,建立动态参数计算模型。利用VRML技术构造可视化加工特征模型,将动态参数映射到加工特征模型上,实现工时定额计算参数的图形化拾取。该技术已应用于企业生产过程中,取得良好的效果。

关键词：工时定额动态参数 VRML

Diagnosis of hepatocellular carcinoma

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World Journal of Gastroenterology 2009年第11期15卷 1301-1314页

作者： Asmaa i Gomaa shahid A Khan Edward LS Leen imam Waked Simon D Taylor-Robinson Department of Hepatology and Gastroenterology Division of Medicine Imperial College London St Mary's Hospital Campus South Wharf Road London W2 1NY United Kingdom National Liver institute Menoufi ya University Shebeen ElKom 32111 Egypt imaging Sciences Department MRC Clinical Sciences Centre Imperial College London Hammersmith Hospital Campus Du Cane Road London W12 0HS United Kingdom

Hepatocellular carcinoma (HCC) is one of the commonest cancers worldwide, particularly in parts of the developing world, and is increasing in incidence. This article reviews the current modalities employed for the diagnosis of HCC, including serum markers, radiological techniques and histological evaluation, and summarises international guidelines for the diagnostic approach to HCC.

关键词： Diagnosis Hepatocellular carcinoma imaging Serum markers

Coherent States of Nonlinear Oscillators with Position-Dependent Mass:Temporal Stability and Fractional Revivals

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Communications in Theoretical Physics 2017年第8期68卷 181-190页

作者： Naila Amir shahid iqbal School of Electrical Engineering and Computer Sciences National University of Sciences and Technology Department of Physics School of Natural Sciences National University of Sciences and Technology

We develop generalized coherent states for a class of nonlinear oscillators with position-dependent effective mass in the context of the Gazeau–Klauder formalism and discuss some of their properties. in order to investigate the temporal evolution we first explore the statistical properties by means of weighting distribution and the Mandel parameter. it is found that the temporal evolution of the coherent states may exhibit the phenomena of quantum revivals and fractional revivals for a particular choice of position-dependent mass oscillator.

关键词： position-dependent effective mass nonlinear oscillators Gazeau–Klauder coherent states Mandel parameter sub-Poissonian statistics temporal stability quantum revivals fractional revivals

Barut–Girardello Coherent States for Nonlinear Oscillator with Position-Dependent Mass

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Communications in Theoretical Physics 2016年第7期65卷 41-48页

Using ladder operators for the non-linear oscillator with position-dependent effective mass, realization of the dynamic group SU(1,1) is presented. Keeping in view the algebraic structure of the non-linear oscillator, coherent states are constructed using Barut–Girardello formalism and their basic properties are discussed. Furthermore, the statistical properties of these states are investigated by means of Mandel parameter and second order correlation function. Moreover,it is shown that in the harmonic limit, all the results obtained for the non-linear oscillator with spatially varying mass reduce to corresponding results of the linear oscillator with constant mass.

关键词： position-dependent mass nonlinear oscillator Schdinger factorization Ladder operators su(1 1) algebra Barut–Girardello coherent states sub-poissonian statistics

Total Fragmentation Cross Section of 158A GeV Lead Projectiles in Cu Target

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Chinese Physics Letters 2008年第9期25卷 3208-3211页

作者： Mukhtar Ahmed Rana shahid Manzoor Physics Division Directorate of Science PINSTECH PO Nilore Islamabad Pakistan

Total fragmentation cross section for the reaction 158A Pb ions ＋ Cu target is measured using the most sensitive track detector CR-39. Measured values are compared with calculations. Exposures of target-detector stack with 158A P5 projectiles are made at CERN-SPS beam facility. Results of calibration of CR-39 detector in a charge region （63 ≤ Z ≤ 83） are also reported, which can be used for high energy particle identification using CR-39 and in determination of partial charge changing cross sections. The charge resolution δz achieved by this technique is about 0.2e. A systematic dependence of total fragmentation cross section on target properties is revealed and the corresponding results are presented.

关键词： the power-law exponents precipitation durative abrupt precipitation change

A Novel Compact Highly isolated UWB MiMO Antenna with WLAN Notch

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Computers, Materials & Continua 2023年第4期75卷 669-681页

作者： Muhammad Awais shahid Bashir Awais Khan Muhammad Asif Nasim Ullah Hend i.Alkhammash Department of Electrical Engineering University of Engineering and TechnologyPeshawar25000Pakistan Department of Electrical Engineering University of Science and TechnologyBannu28100Pakistan Department of Electrical Engineering College of Engineering Taif UniversityAl-HawiyahTaifP.O.Box 888Saudi Arabia Department of Electrical Engineering College of EngineeringTaif UniversityP.O.Box 11099Taif21944Saudi Arabia

This paper presents a compact Multiple input Multiple Output(MiMO)antenna with WLAN band notch for Ultra-Wideband(UWB)*** antenna is designed on 0.8mmthick low-cost FR-4 substrate having a compact size of 22mm×30 *** proposed antenna comprises of two monopole patches on the top layer of substrate while having a shared ground on its bottom *** mutual coupling between adjacent patches has been reduced by using a novel stub with shared ground *** stub consists of complementary rectangular slots that disturb the surface current direction and thus result in reducing mutual coupling between two ports.A slot is etched in the radiating patch for WLAN band *** slot is used to suppress frequencies ranging from 5.1 to 5.9 *** results show that the proposed antenna has a very good impedance bandwidth of|S11|ithin the frequency band from 3.1–14 GHz.A low mutual coupling of less than−23 dB is achieved within the entire UWB ***,the antenna has a peak gain of 5.8 dB,low ECCigh Diversity Gain(DG>9.98).

关键词： Multiple input multiple output(MiMO) ultra-wide band(UWB) defected ground structure envelope correlation coefficient diversity gain