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Chinese Physics B 2016年第4期25卷 358-364页

作者： R M Rosnan Z Othaman R Hussin Ali A Ati Alireza Samavati Shadab Dabagh samad zare Centre for Sustainable Nanomaterials Ibnu Sina Institute for Scientific and Industrial Research Universiti Teknologi Malaysia 81310 Skudai Johor Bahru Malaysia

In this study, nanocrystalline Co-Ni-Mg ferrite powders with composition Coo.5Nio.5-xMgxFe2O4 are successfully synthesized by the co-precipitation method. A systematic investigation on the structural, morphological and magnetic properties of un-doped and Mg-doped Co-Ni ferrite nanoparticles is carried out. The prepared samples are characterized using x-ray diffraction （XRD） analysis, Fourier transform infrared spectroscopy （FTIR）, field emission scanning electron microscopy （FESEM）, and vibrating sample magnetometry （VSM）. The XRD analyses of the synthesized samples confirm the formation of single-phase cubic spinel structures with crystallite sizes in a range of - 32 nm to - 36 nm. The lat- tice constant increases with increasing Mg content. FESEM images show that the synthesized samples are homogeneous with a uniformly distributed grain. The results of IR spectroscopy analysis indicate the formation of functional groups of spinel ferrite in the co-precipitation process. By increasing Mg2- substitution, room temperature magnetic measurement shows that maximum magnetization and coercivity increase from - 57.35 emu/g to - 61.49 emu/g and - 603.26 Oe to 684.11 Oe （l Oe = 79.5775 A.m-l）, respectively. The higher values of magnetization Ms and Mr suggest that the opti- mum composition is Co0.5Ni0.4Mg0.1Fe204 that can be applied to high-density recording media and microwave devices.

关键词： co-precipitation magnetic materials spinel ferrite magnetic properties

Optical behavior of self-assembled high-density Ge nanoislands embedded in SiO_2

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Chinese Optics Letters 2013年第11期11卷 91-95页

作者： Alireza Samavati Zulkafli Othaman Sib Krishna Ghoshal samad zare Ibn Sina Institute for Fundamental Science Studies Universiti Teknologi Malaysia Advanced Optical Material Research Group Department of PhysicsFaculty of ScienceUniversiti Teknologi Malaysia

The radio frequency magnetron sputtering method is used to prepare well-dispersed pyramidal-shaped Ge nanoislands embedded in amorphous SiO2 sublayers of various thicknesses. The estimated size and number density of Ge nanoislands in SiO2 sublayer thicknesses beyond 30 nm are approximately 15 nm and 1011 cm-2, respectively. Atomic force microscopy （AFM） reveals root mean square （RMS） roughness sensitivity as the SiO2 sublayer thickness varies from 30 to 40 nm. The formation of nanoislands with high aspect ratios is attributed to the higher rate of surface reactions between Ge adatoms and nucleated Ge islands than reactions associated with SiO2 and Ge. The Ge nanoisland polyorientation on SiO2 （50-nm thickness） is revealed by X-ray diffraction （XRD） patterns. Photoluminescence （PL） peaks of 2.9 and 1.65 eV observed at room temperature （RT） are attributed to the radiative recombination of electrons and holes from the Ge nanoislands/SiO2 and Si02/Si interfaces, respectively. The mean island sizes are determined by fitting the experimental Raman profile to two models, namely, the phonon confinement model and the size distribution combined with phonon confinement model. The latter model yields the best fit to the experimental data. We confirm that SiO2 matrix thickness variations play a significant role in the formation of Ge nanoislands mediated via the minimization of interfacial and strain energies. OCIS codes： 250.5230, 170.5660.

关键词： Ge SiO high

A Cognitive Study on Politeness Intention Processing and Its Association with Pragmatic Failure in Cross-Cultural Communication

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Chinese Journal of Applied Linguistics 2024年第3期47卷 481-497,525页

作者： Rong YAN Tengfei FENG samad zare Academy of Future Education Xi’an Jiaotong-Liverpool University School of English Language Literature&CultureBeijing International Studies University

Although a large number of studies have focused on various aspects of politeness,very little is known about how politeness intention is activated cognitively during verbal *** present study aims to explore the cognitive mechanism of politeness intention processing,and how it is related to pragmatic failure during cross-cultural *** 30 Chinese EFL university students who were instructed to finish a probe word judgment task with 96 virtual scenarios,the results indicate that within both mono-and cross-cultural contexts,the response time in the experimental scenarios was significantly slower than that of the filler *** suggests that politeness intention was activated while understanding the surface meaning of the conversation;however,the EFL learners could not completely avoid the negative transfer of their native politeness conventions when they were comprehending the conversational intention of the target ***,no significant differences in response time were found between the groups with high and low English pragmatic competence,illustrating that transferring the pragmatic rules and principles into cross-cultural communication skills was more cognitively ***,this study adds to the literature on politeness research and provides some implications for foreign language pragmatic instructions.

关键词： politeness intention cognitive processing pragmatic failure cross-cultural pragmatics cross-cultural communication

Spin Filtering in a Nanowire Superlattice by Dresselhause Spin-Orbit Coupling

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Chinese Physics Letters 2011年第8期28卷 330-332页

作者： samad Javidan Department of physics Faculty of ScienceKNT University of TechnologyP.O.Box 15875-4416TehranIran

An InAs/GaSb nanowire superlattice using GaAs for the impure layers is *** spin-orbit coupling eliminates spin degeneracy,induces one miniband in the superlattices to split into two minibands and leads to complete spi... 详细信息

关键词： InAs/GaSb polarization Coupling

Mineralogy and Geochemistry of Major, Trace and Rare Earth Elements in Sediments of the Hypersaline Urmia Salt Lake, Iran

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Acta Geologica Sinica(English Edition) 2018年第4期92卷 1384-1395页

作者： samad ALIPOUR Khadije MOSAVI ONLAGHI Geology Department Faculty of Sciences UrmiaUniversity Urmia Iran Urmia University Urmia Iran

Urmia Salt Lake （USL） is a hypersaline lake located at the NW corner of the Iran platform. The lake area is estimated to have been over 5000 km2 at one point, but has now decreased to 〈1000 km^2 in the last two decades. It contains 4.6×109 tons of halite and other detrital and evaporative minerals such as calcite, aragonite, dolomite, quartz, feldspars, augite and sylvite. This study examined the mineralogy and geochemistry of bed sediments along the mid-east toward NE bank sediments collected from 1.5 meters depth and nearby augite placer. Due to the diverse iithology of the surrounding geology, bed sediments vary from felsic in the mid-east to mafic in the northeast. Weathering of tephrite and adakite rocks of the Islamic Island at the immediate boundary has produced a large volume of augite placer over a 40 km length, parallel to the shoreline. Based on the study result, weathering increases from south to north and the geochemistry of the sediments shows enrichment of MgO, CaO, Sr and Ba associated with Sr deployment in all samples. Rare earth elements （REE） patterns normalized to the upper continental crust （UCC） indicated LREEs enrichment compared to HREEs with an elevated anomaly of Eu, possibly due to surface absorbance of Mn and Fe minerals, associated with Sr elevation originating from adakites in the lake basin vicinity.

关键词： mineralogy geochemistry augite placer Urmia Lake Iran

A perspective on 3D bioprinting in tissue regeneration

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Bio-Design and Manufacturing 2018年第3期1卷 157-160页

作者： samad Ahadian Ali Khademhosseini Department of Bioengineering University of California Los Angeles CA 90095-1600 USA Center for Minimally Invasive Therapeutics (C-MIT) University of California Los Angeles CA 90095-1600 USA California NanoSystems Institute (CNSI) University of California Los Angeles CA 90095-1600 USA Department of Radiological Sciences University of California Los Angeles CA 90095-1600 USA Department of Chemical and Biomolecular Engineering University of California Los Angeles CA 90095-1600 USA

IntroductionA rapidly increasing need for organ transplantation and short list of donated organs have led to the development of new materials and technologies for organ manufacturing. Although some simple organs, such as skin and cartilage, have been successfully fabricated and commercialized, it is still difficult to make tissues and organs with high complexity. Engineered tissues have other biomedical applications, such as drug screening models and bio-actuators. Threedimensional （3D） bioprinting has become a great tool to fabricate tissue constructs on demand for transplantation and other biomedical applications.

关键词：器官移植生物材料生物技术发展现状

Smart scaffolds in tissue regeneration

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Regenerative Biomaterials 2018年第3期5卷 125-128页

作者： samad Ahadian Ali Khademhosseini Toronto General Research Institute University Health NetworkTorontoON M5G 2C4Canada Department of Bioengineering Department of Radiology Department of Chemical and Biomolecular Engineering Center for Minimally Invasive Therapeutics(C-MIT) California NanoSystems Institute(CNSI) University of CaliforniaLos AngelesCA 90095-1600USA

Recent advances in biofabrication technologies and chemical synthesis approaches have enabled the fabrication of smart scaffolds that aim to mimic the dynamic nature of the native extracellular *** scaffolds have pave... 详细信息

关键词： drug delivery scaffolds regenerative mechanism

Studies on batch adsorptive removal of cadmium and nickel from synthetic waste water using silty clay originated from Balochistan-Pakistan

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Chinese Journal of Chemical Engineering 2020年第4期28卷 1171-1176页

作者： Abdul samad Muhammad Imran Din Mahmood Ahmed Institute of Chemistry University of the PunjabLahore 54590Pakistan Renacon Pharma Limited Lahore 54600Pakistan

The potentials of silty clay(SC),acquired from Chaman,Balochistan,were investigated as adsorbent for Ni(Ⅱ)and Cd(Ⅱ)removal from contaminated *** influence of different operating factors like dose,pH,temperature,and time of contact was explored,and optimum values were noted under batch adsorption *** study was conducted with varying concentrations of solutions on optimized conditions and different adsorption models i.e.,Langmuir,Freundlich,Temkin and Dubinin-Radushkevich(D-R)isotherm,which were employed to interpret the *** isothermal data of both Ni(Ⅱ)and Cd(Ⅱ)were well fitted to Langmuir isotherm suggesting the formation of monolayer of metal ions on silty *** values of adsorption capacity noted for Ni(Ⅱ)and Cd(Ⅱ)were 3.603 mg·g^-1 and 5.480 mg·g^-1,*** studies affirmed that pseudo second order(PSO)kinetics was being obeyed by the removal of Ni(Ⅱ)and Cd(Ⅱ).Thermodynamic variables like free energy change(ΔG°),enthalpy change(ΔH°)and entropy change(ΔS°)were *** negative value ofΔG°and the positive values ofΔH°andΔS°unfolded that the removal process of both metal ions of by SC was spontaneous,endothermic and feasible.

关键词： Adsorption Kinetics Isotherm Toxicity Silty clay Thermodynamics

Analysis and Modeling of Propagation in Tunnel at 3.7 and 28 GHz

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Computers, Materials & Continua 2022年第5期71卷 3127-3143页

作者： Md Abdus samad Dong-You Choi Department of Information and Communication Engineering Chosun UniversityGwangju61452Korea Department of Electronics and Telecommunication Engineering International Islamic University ChittagongChittagong4318Bangladesh

In present-day society,train tunnels are extensively used as a means of ***,to ensure safety,streamlined train operations,and uninterrupted internet access inside train tunnels,reliable wave propagation modeling is *** have experimented and measured wave propagation models in a 1674 m long straight train tunnel in South *** measured path loss and the received signal strength were modeled with the Close-In(CI),Floating intercept(FI),CI model with a frequency-weighted path loss exponent(CIF),and alpha-beta-gamma(ABG)models,where the model parameters were determined using minimum mean square error(MMSE)*** measured and the CI,FI,CIF,and ABG modelderived path loss was plotted in graphs,and the model closest to the measured path loss was identified through *** on the measured results,it was observed that every model had a comparatively lower(n<2)path loss exponent(PLE)inside the *** also determined the path loss component’s possible deviation(shadow factor)through a Gaussian distribution considering zero mean and standard deviation calculations of random error *** FI model outperformed all the examined models as it yielded a path loss closer to the measured datasets,as well as a minimum standard deviation of the shadow factor.

关键词： Path loss shadow factor telecommunications train tunnel wave propagation wireless networks

Synthesis of zinc oxide nanoparticles reinforced clay and their applications for removal of Pb(II)ions from aqueous media

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Chinese Journal of Chemical Engineering 2021年第4期34卷 454-461页

作者： Abdul samad Muhammad Imran Din Mahmood Ahmed Saghir Ahmad Institute of Chemistry University of the PunjabLahore 54590Pakistan Renacon Pharma Limited Lahore 54600Pakistan

The aim of the study was to synthesize zinc oxide nanoparticles(ZnONPs)composite with clay by a novel route and then to explore the capability of composite of ZnONPs and silty clay(SC)as adsorbents for Pb(II)eradication from aqueous media by batch adsorption *** effect of different operating factors like temperature,pH,dose and time of contact on the adsorption process were studied to optimize the ***,Freundlich,Dubinin-Radushkevich(DR)and Temkin isotherms were applied for the interpretation of the *** R^(2)and q values obtained from Langmuir model suggested that the process is best interpreted by this *** values of adsorption capacity(qm)noted were 12.43 mg·g^(-1) and 14.54 mg·g^(-1)on SC and ZnONPsSC *** kinetic studies exposed that pseudo second order(PSO)kinetics is followed by the processes suggesting that more than one steps are involved to control the rate of *** thermodynamic variables such as change in free energy(AGe),change in enthalpy(AH9)and change in entropy(ASe)were *** data suggested that Pb(II)adsorption on SC and ZnONPsSC are spontaneous,endothermic and feasible processes.

关键词： Adsorption Isotherm Kinetics Silty clay Thermodynamic