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Communications in Theoretical Physics 2016年第8期65卷 237-243页

作者： M.Mobaraki s.jafari Department of Physics University of Guilan

In this paper, the nonlinear interaction of ultra-high power laser beam with fusion plasma at relativistic regime in the presence of obliquely external magnetic field has been studied. Imposing an external magnetic field on plasma can modify the density profile of the plasma so that the thermal conductivity of electrons reduces which is considered to be the decrease of the threshold energy for ignition. To achieve the fusion of Hydrogen–Boron(HB) fuel,the block acceleration model of plasma is employed. Energy production by HB isotopes can be of interest, since its reaction does not generate radioactive tritium. By using the inhibit factor in the block model acceleration of plasma and Maxwell's as well as the momentum transfer equations, the electron density distribution and dielectric permittivity of the plasma medium are obtained. Numerical results indicate that with increasing the intensity of the external magnetic field, the oscillation of the laser magnetic field decreases, while the dielectric permittivity increases. Moreover, the amplitude of the electron density becomes highly peaked and the plasma electrons are strongly bunched with increasing the intensity of external magnetic field. Therefore, the magnetized plasma can act as a positive focusing lens to enhance the fusion process. Besides, we find that with increasing θ-angle(from oblique external magnetic field) between 0 and 90°, the dielectric permittivity increases, while for θ between 90° and 180°, the dielectric permittivity decreases with increasing θ.

关键词： laser-plasma interaction external magnetic field laser fusion HB fuel

Gain calculation of a free-electron laser operating with a non-uniform ion-channel guide

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Chinese Physics B 2011年第9期20卷 187-191页

作者： A.Hasanbeigi H.Mehdian s.jafari Department of Physics and Plasma Research Institute of Tarbiat Moallem University 49 Dr Mofatteh AvenueTehran 15614Iran Department of Physics University of GuilanRasht 41335-1914Iran

Amplification of an electromagnetic wave by a free electron laser （FEL） with a helical wiggler and an ion channel with a periodically varying ion density is examined. The relativistic equation of motion for a single electron in the combined wiggler and the periodic ionbchannel fields is solved and the classes of possible trajectories in this configuration are discussed. The gain equation for the FEL in the low-gain-per-pass lirnit is obtained by adding the effect of the periodic ion channel. Numerical calculation is employed to analyse the gain induced by the effects of the non-uniform ion density. The variation of gain with ion-channel density is demonstrated. It is shown that there is a gain enhancement for group I orbits in the presence of a non-uniform ion-channel but not in a uniform one. It is also shown that periodic ion-channel guiding is used to reach the maximum peak gain in a low ion-channel frequency （low ion density）.

关键词： free electron laser nonuniform ion-channel helical wiggler

Nonlinear Free Vibration of Reinforced skew Plates with sWCNs Due to Finite strain

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Advances in Applied Mathematics and Mechanics 2018年第6期10卷 1344-1364页

作者： s.jafari Mehrabadi s.M.Nodeh Farahani Department of Mechanical Engineering Arak BranchIslamic Azad UniversityArakIran Department of Mechanical Engineering Kashan UniversityKashanIran

This paper is an attempt to investigate the nonlinear free vibration of skew plates reinforced by carbon nanotubes(CNTs)due to finite strain *** material properties of the nano-composite are estimated using the molecular dynamic results and the rule of ***,the differential equations governing the motions are derived on the basis of Classical Plate Theory(CPT)regarding the nonlinear Green-Lagrange strain *** order to solve the nonlinear equations,Galerkin’s method,Frechet derivative and differential quadrature method are *** effects of volume fraction of functionally graded materials(FGM),skew angle,distribution of CNTs and geometrical features of the plate on the nonlinear vibration of system have been *** results of this study have been compared with other researches and a good agreement has been achieved.

关键词： Finite strains nonlinear vibration skew plate carbon nanotubes functionally graded materials

Fusion Energy and stopping Power in a Degenerate DT Pellet Driven by a Laser-Accelerated Proton Beam

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Communications in Theoretical Physics 2016年第6期65卷 761-766页

作者： M.Mehrangiz A.Ghasemizad s.jafari B.Khanbabaei Department of Physics University of Guilan Department of Physics Damghan University

In this paper, we have improved the fast ignition scheme in order to have more authority needed for highenergy-gain. Due to the more penetrability and energy deposition of the particle beams in fusion targets, we employ a laser-to-ion converter foil as a scheme for generating energetic ion beams to ignite the fusion fuel. We find the favorable intensity and wavelength of incident laser by evaluating the laser-proton conversion gain. By calculating the source-target distance, proton beam power and energy are estimated. Our analysis is generalized to the plasma degeneracy effects which can increase the fusion gain several orders of magnitude by decreasing the ion-electron collisions in the *** is found that the wavelength of 0.53 μm and the intensity of about 1020W/cm^2, by saving about 10% conversion coefficient, are the suitable measured values for converting a laser into protons. Besides, stopping power and fusion burn calculations have been done in degenerate and non-degenerate plasma mediums. The results indicate that in the presence of degeneracy, the rate of fusion enhances.

关键词： proton fast ignition degenerate plasma laser-to-proton converter foil stopping power

Free Vibration Analysis of Nanocomposite Plates Reinforced by Graded Carbon Nanotubes Based on First-Order shear Deformation Plate Theory

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Advances in Applied Mathematics and Mechanics 2013年第1期5卷 90-112页

作者： s.jafari Mehrabadi B.sobhaniaragh V.Pourdonya Department of Mechanical Engineering Arak BranchIslamic Azad UniversityArakIran Young Researchers Club Arak BranchIslamic Azad UniversityArakIran

Based on the Mindlin’s first-order shear deformation plate theory this paper focuses on the free vibration behavior of functionally graded nanocomposite plates reinforced by aligned and straight single-walled carbon nanotubes(sWCNTs).The material properties of simply supported functionally graded carbon nanotube-reinforced(FGCNTR)plates are assumed to be graded in the thickness *** effective material properties at a point are estimated by either the Eshelby-Mori-Tanaka approach or the extended rule of *** types of symmetric carbon nanotubes(CNTs)volume fraction profiles are presented in this *** equations of motion and related boundary conditions are derived using the Hamilton’s principle.A semianalytical solution composed of generalized differential quadrature(GDQ)method,as an efficient and accurate numerical method,and series solution is adopted to solve the equations of *** primary contribution of the present work is to provide a comparative study of the natural frequencies obtained by extended rule of mixture and Eshelby-Mori-Tanaka *** detailed parametric studies are carried out to study the influences various types of the CNTs volume fraction profiles,geometrical parameters and CNTs volume fraction on the free vibration characteristics of FGCNTR *** results reveal that the prediction methods of effective material properties have an insignificant influence of the variation of the frequency parameters with the plate aspect ratio and the CNTs volume fraction.

关键词： Carbon nanotube-reinforced functionally graded Hamilton’s principle EshelbyMori-Tanaka symmetric profiles extended rule of mixture

Vibration Behavior of a sandwich Porous Elliptical Micro-shell with a Magneto-Rheological Core Based on the Modified Couple stress Theory

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Advances in Applied Mathematics and Mechanics 2023年第6期15卷 1655-1698页

作者： A.Mohammadpour s.jafari Mehrabadi P.Yousefi H.Mohseni Monfared Department of Mechanical Engineering Islamic Azad UniversityArak Branch.ArakIran

Recently,the use of porous materials has grown widely in many structures,such as beams,plates,and *** characteristics of porous materials change in the thickness direction by different *** study has investigated the free vibration analysis of a sandwich porous elliptical micro-shell with a magneto-rheological fluid(MRF)core for the first ***,we examined the displacement of the middle layer’s macro-and micro-components,using Love’s shell ***,we used the modified couple stress theory(MCsT)to obtain the strain and symmetrical curvature tensors for the three *** Hamilton’s principle was implemented to derive the equations of *** also used the Galerkin’s method to solve the equations of motion,resulting in a system of equations in the form of a linear eigenvalue *** solving the governing equations,we obtained the various natural frequencies and loss factors of the elliptical micro-shell,and compared them with the results in earlier ***,we investigated the effects of thickness,porosity distribution pattern,aspect ratio,length scale parameter,and magnetic field intensity on the natural frequency and loss factor of the *** data accuracy was validated by comparing them with those of reputable previous articles.

关键词： Elliptical micro shell free vibration magneto-rheological core modified couple stress theory sandwich porous material

Theoretical framework of the Isfahani style: Inspiring sustainable aspects of a vernacular urban development

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Frontiers of Architectural Research 2024年第2期13卷 349-369页

作者： Hatef jafari sharami seyed Jamalaldin Hosseini Department of Architecture and Urbanism University of EyvanekeyEyvanekey 99888-35918Iran Faculty of Civil and Architecture University of EyvanekeyEyvanekey 99888-35918Iran

The Isfahani style represents a method of traditional Iranian architecture and urban development that existed in the early 20th century and is regarded as a leading model in most traditional Iranian cities. It exhibits several vigorous features contributing to its recognition as a traditional approach to sustainable architecture and urban development. This research endeavors to reveal a theoretical framework beneath these inspiring aspects using the typology of sustainable modern forms, including the hierarchy, passive design strategies, compactness, density, diversity, mixed land use, pluralism, balance, good composition, and integration over time. To this end, the study employs qualitative research methods, drawing from traditional samples, to identify innovative, energy and socially efficient, and low-impact strategies implemented in this vernacular architecture of Iran's semi-arid and hot climates. The findings revealed that the neighborhood concept as a local and plural community (Mahalla) was a vital phenomenon in Iran's urban development. Apparently, the demise of this paradigm effectively played an important role in the numerous challenges regarding the social, energy, and economic viability of modern Iranian cities. Hence, this study presented theoretical frameworks—aligned with sustainable concepts—from the Isfahani style through its analysis, classification, and interpretation, which can contribute to modern urban development.

关键词： Isfahani style Vernacular urban development sustainable urban development Iranian cities Vernacular architecture

Nurses'attitude toward patients'safety climate during COVID-19 pandemic:a cross-sectional study

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Frontiers of Nursing 2024年第1期11卷 39-46页

作者： Asra Nassehi Kobra Ghorbanzadeh somaye Moayedi Javad jafari Parvin Mahmoodi Mojtaba jafari Department of Nursing Bam University of Medical SciencesBamIran Department of Nursing Khalkhal University of Medical SciencesKhalkhalIran Community Nursing Research Center Department of NursingZahedan University of Medical SciencesZahedanIran Clinical Care Research Center Department of NursingNursing and Midwifery SchoolKurdistan University of Medical SciencesSanandajIran

Objective:Patient safety is a fundamental factor in improving the quality of care provided in ***,it is considered a significant parameter by all healthcare organizations around the *** present study was conducted to investigate the attitude of nurses toward the patient safety climate during the Coronavirus Disease 2019(COVID-19)pandemic in the southeast of ***:This is a cross-sectional descriptive *** all the nurses working in one of the hospitals in the southeast of Iran,171 nurses participated in the study through convenience sampling *** survey was conducted between June 1 and July 30,2020.A 2-part questionnaire including demographic information and an assessment of nurses'attitudes toward patients'safety climate was used for data collection in *** content validity of the scale is(0.77)and reliability was re-calculated and confirmed by the present study with Cronbach's alpha(α=0.9).Data were analyzed by sPss 20(IBM Corporation,Armonk,New York,United states)using descriptive and analytical statistical ***:The mean score of safety climates was 3.2±5.20(out of 5 scores).The results showed that among all dimensions of the safety climate,only the education dimension was statistically significant between males and females(Pso,there was a significant relationship between the overall average of the safety climate and its dimensions according to the people's position only in the dimension of supervisors'attitude(Psignificant correlation between the education level and the overall score of safety climate(Ps well as the supervisor's attitude dimension(Ps ***:The results showed that the safety climate was at a relatively favorable *** the impact of nurses'attitudes on the safety climate of patients,its improvement seems *** is recommended to design training courses and educate nurses in order to promote a p

关键词： COVID-19 Iran nurses patient safety climate

Late infection after peri-orbital autologous micro-fat graft:a case presentation and literature review

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 603-606页

作者： Farzad Pakdel Hassan Asadigandomani Melika Arab Bafrani Zohreh Nozarian Zohre Abedinifar Niloofar Pirmarzdashti Behzad jafari Zaynab siami Department of Oculofacial Plastic surgery Farabi HospitalSchool of MedicineTehran University of Medical SciencesTehran ***Iran Craniomaxillofacial Research Center Tehran University of Medical SciencesTehran ***Iran Department of Ophthalmology School of MedicineTehran University of Medical SciencesTehran ***Iran Department of Pathology Farabi HospitalSchool of MedicineTehran University of Medical SciencesTehran ***Iran Department of Microbiology Farabi HospitalSchool of MedicineTehran University of Medical SciencesTehran ***Iran Pediatric Cell and Gene Therapy Research Center Children’s Medical CenterSchool of MedicineTehran University of Medical SciencesTehran ***Iran

Citation:Pakdel F,Asadigandomani H,Arab Bafrani M,Nozarian Z,Abedinifar Z,Pirmarzdashti N,jafari B,siami *** infection after peri-orbital autologous micro-fat graft:a case presentation and literature *** J Ophthalmol ... 详细信息

关键词： graft orbital after

Correction:Integration of light and hormone signaling pathways in the regulation of plant shade avoidance syndrome

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aBIOTECH 2024年第1期5卷 115-115页

作者： Yang Liu Fereshteh jafari Haiyang Wang Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China state Key Laboratory for Conservation and Utilization of subtropical Agro-Bioresources South China Agricultural UniversityGuangzhou 510642China Guangdong Laboratory for Lingnan Modern Agriculture Guangzhou 510642China

Correction:aBI0TECH(2021)2:131-145 https://doi.0rg/10.1007/s42994-021-00038-1 In this article the author's name Fereshteh jafari was incorrectly written as Feresheeh *** original article has been *** Access This article is licensed under a Creative Commons Attribution 4.0 International License,which permits use,sharing,adaptation,distribution and reproduction in any medium or format.

关键词： Integration Open Creative