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Journal of Natural Gas Chemistry 2010年第5期19卷 548-551页

作者： A.m.Rashidi A.Karimi H.R.Bozorgzadeh K.Kashefi m.zare Nanotechnology Research Center Research Institute of petroleum industry (RIPI)West Blvd.Azadi Sport ComplexP.O.Box: 14665-1998TehranIran

Single-wall carbon nanotubes （SWNTs） with high surface area were synthesized over nanoporous Co-mo/mgO by a chemical vapor deposition （CVD） method. The SWNTs were used as catalyst support for selective hydrogenation of syngas to hydrocarbons. Here an extensive study of Fischer-Tropsch synthesis （FTS） on CNT-supported cobalt catalysts with different amounts of cobalt loading up to 40 wt% is reported. The catalysts were characterized by different methods including N2 adsorption-desorption, X-ray diffraction, hydrogen chemisorption, inductively coupled plasma （ICP） and temperature-programmed reduction. Enhancement of the reducibility of Co3O4 to CoO, CoO to Co° and small cobalt oxide particles, dispersion of the cobalt, and activity and selectivity of FTS were investigated and compared with a conventional support. The CNT supported catalysts achieve a high dispersion and high loading of the active metal, cobalt in particular, so that the bulk formation of cobalt metal, which tends to occur in conventional support, can be avoided. The results showed that the specific activity of CNT supported catalysts increase significantly （there is a two fold increase in CO Conversion per gram of the active metal） with respect to the conventional supported catalyst.

关键词： CNT SWNTs Fiscber-Tropsch cobalt reducibility activity C5+ selectivity

Novel Conductive PANI/Hydrophilic Thiacalix[4]arene Nanocomposites: Synthesis, Characterization and Investigation of Properties

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Chinese Journal of Polymer Science 2014年第2期32卷 218-229页

作者： Rafieh-Sadat Norouzian moslem m.Lakouraj Ehsan N.zare Polymer Chemistry Research Laboratory Department of Organic Chemistry Faculty of Chemistry University of Mazandaran

Nanocomposites of polyaniline （PANI） and the macrocycle thiacalix[4]arene tetra sulfonate （TCAS） were successfully synthesized in feed ratios of 1：0.25, 1：0.50 and 1：0.75 by three prevail synthetic methods, i.e. in situ polymerization, emulsion polymerization and solution casting technique. The structures of the nanocomposites were confirmed by FTIR, UV-Vis, XRD, SEm, and TEm techniques. The conductivity was measured by a four probe method. The conductivity was recorded to be as high as 105 x 10-2 ***-~ for the nanocomposite with a nanometer size structure and homogeneously distributed morphology. The electroactivity of the nanocomposites was approved by cyclic voltammetry （CV） and impedance spectroscopy technique （EIS）. The antioxidant ability and thermal property of the composites were further studied. Preliminary studies have evidenced the production of conductive nanocomposites with good thermal property and relatively good solubility in N-methyl 2-pyrrolidone （NmP）, with the antioxidant activity reaching up to 80%.

关键词： Thiacalixarene Nanocomposite Polyaniline Conductivity Antioxidant.

Supposition of graphene stacks to estimate the contact resistance and conductivity of nanocomposites

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Applied mathematics and mechanics(English Edition) 2024年第4期45卷 663-676页

作者： Y.zare m.T.mUNIR G.J.WENG K.Y.RHEE Biomaterials and Tissue Engineering Research Group Department of Interdisciplinary TechnologiesBreast Cancer Research CenterMotamed Cancer InstituteTehran ***Iran College of Engineering and Technology American University of the Middle EastEgaila 54200Kuwait Department of mechanical and Aerospace Engineering Rutgers UniversityNew BrunswickNJ 08903U.S.A. Department of mechanical Engineering(BK21 Four) College of EngineeringKyung Hee UniversityYongin 446701Republic of Korea

In this study,the effects of stacked nanosheets and the surrounding interphase zone on the resistance of the contact region between nanosheets and the tunneling conductivity of samples are evaluated with developed equations superior to those previously *** contact resistance and nanocomposite conductivity are modeled by several influencing factors,including stack properties,interphase depth,tunneling size,and contact *** developed model's accuracy is verified through numerous experimental *** further validate the models and establish correlations between parameters,the effects of all the variables on contact resistance and nanocomposite conductivity are ***,the contact resistance is primarily dependent on the polymer tunnel resistivity,contact area,and tunneling *** dimensions of the graphene nanosheets significantly influence the conductivity,which ranges from 0 S/m to90 S/*** increased number of nanosheets in stacks and a larger gap between them enhance the nanocomposite's ***,the thicker interphase and smaller tunneling size can lead to higher sample conductivity due to their optimistic effects on the percolation threshold and network efficacy.

关键词： graphene polymer composite stacked nanosheet tunneling conductivity contact resistance interphase

Effects of mg substitution on the structural and magnetic properties of Co0.5Ni（0.5-x）mgxFe2O4 nanoparticle ferrites

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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

Nonlinear forced vibration in a subcritical regime of a porous functionally graded pipe conveying fluid with a retaining clip

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Applied mathematics and mechanics(English Edition) 2025年第1期46卷 101-122页

作者： m.GHOLAmI m.EFTEKHARI Department of mechanical Engineering Shahid Bahonar University of Kerman

This study examines the nonlinear behaviors of a clamped-clamped porous pipe made of a functionally graded material(FGm) that conveys fluids and is equipped with a retaining clip, focusing on primary resonance and subcritical dynamics. The nonlinear governing equations for the FGm pipe are derived by the extended Hamilton's principle, and subsequently discretized through the application of the Galerkin *** direct method of multi-scales is then used to solve the derived equations. A thorough analysis of various parameters, including the clip stiffness, the power-law index, the porosity, and the clip location, is conducted to gain a comprehensive understanding of the system's nonlinear dynamics. Through the analysis of the first natural frequency, the study highlights the influence of the flow velocity and the clip stiffness, while the comparisons with metallic pipes emphasize the role of FGm composition. The examination of the forced response curves reveals saddle-node bifurcations and their dependence on parameters such as the detuning parameter and the power-law index, offering valuable insights into the system's nonlinear resonant behavior. Furthermore, the frequency-response curves illustrate the hardening nonlinearities influenced by factors such as the porosity and the clip stiffness, revealing nuanced effects on the system response and resonance characteristics. This comprehensive analysis enhances the understanding of nonlinear behaviors in FGm porous pipes with a retaining clip, providing key insights for practical engineering applications in system design and optimization.

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Development of a Circuit-theory Based Transmission Cost Allocation method by Orthogonal Projection and Equal-sharing Principle

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CSEE Journal of Power and Energy Systems 2019年第2期5卷 159-170页

作者： Saeid Pouyafar mehrdad Tarafdar Hagh Kazem.zare Department of Electrical and Computer Engineering University of TabrizTabrizIran.M.T.Hagh is also with Engineering FacultyNear East University99138 NicosiaNorth CyprusMersin 10Turkey

This paper presents a new solution to the problem of transmission cost allocation to its *** proposed technique utilizes modified Z-bus theory,equivalent current injection and impedance of the generators and loads,and is developed by the equal-sharing as well as the orthogonal projection *** procedure is performed in three ***,the modified Z-bus theory is used to calculate the contribution of the users into the network bus voltages as well as the branch ***,the equal sharing principle is confirmed by the game theory solutions and is subsequently applied to identify the users’contributions into the branch power *** that,the orthogonal projections of the contributions are calculated and the concept of effective contributions is *** proposed methodology provides the percentage shares of the users on the network complex variables,which help to better assess the contributions.A 2-bus and the IEEE 30-bus test system are used to validate the proposed ***,the proposed methodology is applied to the polish 2383-bus system to emphasize its applicability to large practical systems.

关键词： Effective contribution equal sharing of interaction-terms modified impedance matrix orthogonal projection concept transmission cost allocation

Reduced graphene oxide-grafted bovine serum albumin/bredigite nanocomposites with high mechanical properties and excellent osteogenic bioactivity for bone tissue engineering

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Bio-Design and manufacturing 2021年第2期4卷 243-257页

作者： Esfandyar Askari mohammad Rasouli Seyedeh F.Darghiasi Seyed m.Naghib Yasser zare Kyong Y.Rhee Nanotechnology Department School of Advanced TechnologiesIran University of Science and Technology(IUST)P.O.Box 16846-13114TehranIran Biomaterials and Tissue Engineering Research Group Department of Interdisciplinary TechnologiesBreast Cancer Research CenterMotamed Cancer InstituteACECRTehranIran Department of mechanical Engineering College of EngineeringKyung Hee UniversityYongin 446-701Republic of Korea

The optimization of the scaffolds to provide a suitable matrix and accelerate the regeneration process is vital for bone tissue ***,poor mechanical and biological characteristics remain the primary challenges that must be *** example,although bredigite(Br)has shown great potential for application in bone tissue engineering,it easily fails in *** the present work,these challenges are addressed by reinforcing the Br matrix with nanosheets of graphene oxide(rGO)that have been reduced by bovine serum albumin(BSA)in order to enhance the mechanical properties and biological *** reduction of graphene oxide by BSA improves the water stability of the nanosheets and provides an electrostatic interaction between theBSA-rGO nanosheets and theBr *** high thermal conductivity of theBSA-rGO nanosheets decreases the porosity of the Br by transferring heat to the core of the ***,the addition of BSA-rGO nanosheets into the Br matrix enhances the adhesion of G-292 cells on the surface of the *** findings suggest that the tablet consisting of BSA-rGO-reinforced Br has encouraging potential for application in bone tissue engineering.

关键词： Bovine serum albumin(BSA) Reduced graphene oxide(rGO) Bredigite mechanical properties Bone tissue engineering

Surfactant assisted solvothermal synthesis of ZnO nanoparticles and study of their antimicrobial and antioxidant properties

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Journal of materials Science & Technology 2018年第6期34卷 1035-1043页

作者： mina zare K. Namratha K. Byrappa D.m. Surendra S. Yallappa Basavaraj Hungun Centre for materials Science and Technology Vijnana Bhavan University of Mysore 570006 India DOS in Earth Science University of Mysore Vijnana Bhavan Manasagangotri Mysore 570 006 India Dept. of Chemistry Gokhale Centenary College Ankola 581314 Uttara Kannada India Department ofBiotechnology KLE Technological University Hubballi 580031 India

This study demonstrated a solvothermal method of growth of three different morphologies of zinc oxide nanoparticles （ZnO NPs）： i） flower-like nanorod and nanoflakes, ii） assembled hierarchical structure, and iii） nano granule. Oleic acid （C18H3402）, gluconic acid （C6H1207） and tween 80 （C64H124026） were used as surfactant/capping/reducing agent for the formation of different morphologies of nanoparticles. The as-synthesized ZnO NPs were characterized by different physicochemical techniques such as UV-vis （UV-vis） spectroscopy, X-ray diffraction （XRD）, fourier transform infrared spectroscopy （FFIR）, field emission scanning electron microscopy （FE-SEm）, energy dispersive X-ray （EDX） analysis and dynamic light scattering （DLS） studies. Further, the antioxidant and antimicrobial activity of these nanostructures was evaluated. The antioxidant activity of these nanostructures was assessed via 2,2-diphenyl,1-1 picrylhydrazyl （DPPH）, 2,2＇-azino-bis （3-ethylbenzothiazoline-6-sulphonic acid）（ABTS） and H202 free radical scavenging activity. The in vitro antimicrobial activity of the obtained nanostructures was demonstrated against both gram negative （Escherichia coil） and gram positive （Staphylococcus aureus） bacterial genera. This study revealed antioxidant and antimicrobial properties of different structures ofZnO NPs suggesting their biomedical and industrial applications.

关键词： ZnO nanoparticles Solvothermal method Nanorods Nanoflakes[k]Nano granule Antioxidant & antimicrobial studies

Neurogenesis dynamics in the olfactory bulb:deciphering circuitry organization, function, and adaptive plasticity

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Neural Regeneration Research 2025年第6期20卷 1565-1581页

作者： moawiah m.Naffaa Department of Psychology and Neuroscience Duke UniversityDurhamNCUSA Department of Cell Biology Duke University School of MedicineDurhamNCUSA

Adult neurogenesis persists after birth in the subventricular zone, with new neurons migrating to the granule cell layer and glomerular layers of the olfactory bulb, where they integrate into existing circuitry as inhibitory interneurons. The generation of these new neurons in the olfactory bulb supports both structural and functional plasticity, aiding in circuit remodeling triggered by memory and learning processes. However, the presence of these neurons, coupled with the cellular diversity within the olfactory bulb, presents an ongoing challenge in understanding its network organization and function. moreover,the continuous integration of new neurons in the olfactory bulb plays a pivotal role in regulating olfactory information processing. This adaptive process responds to changes in epithelial composition and contributes to the formation of olfactory memories by modulating cellular connectivity within the olfactory bulb and interacting intricately with higher-order brain regions. The role of adult neurogenesis in olfactory bulb functions remains a topic of debate. Nevertheless, the functionality of the olfactory bulb is intricately linked to the organization of granule cells around mitral and tufted cells. This organizational pattern significantly impacts output, network behavior, and synaptic plasticity, which are crucial for olfactory perception and memory. Additionally, this organization is further shaped by axon terminals originating from cortical and subcortical regions. Despite the crucial role of olfactory bulb in brain functions and behaviors related to olfaction, these complex and highly interconnected processes have not been comprehensively studied as a whole. Therefore, this manuscript aims to discuss our current understanding and explore how neural plasticity and olfactory neurogenesis contribute to enhancing the adaptability of the olfactory system. These mechanisms are thought to support olfactory learning and memory, potentially through increased

关键词： network adaptability neurogenesis neuronal communication olfactory bulb olfactory learning olfactory memory synaptic plasticity

Probabilistic prediction of expected ground condition and construction time and costs in road tunnels

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Journal of Rock mechanics and Geotechnical Engineering 2016年第5期8卷 734-745页

作者： A.mahmoodzadeh S.zare School of mining Petroleum and Geophysics EngineeringShahrood University of Technology

Ground condition and construction （excavation and support） time and costs are the key factors in decision-making during planning and design phases of a tunnel project. An innovative methodology for probabilistic estimation of ground condition and construction time and costs is proposed, which is an integration of the ground prediction approach based on markov process, and the time and cost variance analysis based on monte-Carlo （mC） simulation. The former provides the probabilistic description of ground classification along tunnel alignment according to the geological information revealed from geological profile and boreholes. The latter provides the probabilistic description of the expected construction time and costs for each operation according to the survey feedbacks from experts. Then an engineering application to Hamro tunnel is presented to demonstrate how the ground condition and the construction time and costs are estimated in a probabilistic way. In most items, in order to estimate the data needed for this methodology, a number of questionnaires are distributed among the tunneling experts and finally the mean values of the respondents are applied. These facilitate both the owners and the contractors to be aware of the risk that they should carry before construction, and are useful for both tendering and bidding.

关键词： markov process Geological condition monte-Carlo (mC) simulation Construction time and costs Hamro tunnel