Estimation of lattice strain in metallic oxide–organic material nanocomposite using Williamson-Hall equation M Roodbari Shahmiri گروه فیزیک حالت جامد، دانشکده علوم پایه، دانشگاه مازندران، بابلسر author A Bahari گروه فیزیک حالت جامد، دانشکده علوم پایه، دانشگاه مازندران، بابلسر author F Rostamian گروه فیزیک حالت جامد، دانشکده علوم پایه، دانشگاه مازندران، بابلسر author M Baradaran Khaniani گروه فیزیک حالت جامد، دانشکده علوم پایه، دانشگاه مازندران، بابلسر author text article 2019 per In the present work, metallic oxide–organic material hybrid nanocomposites (Poly vinyl pyrrolidone- zinc oxide, PVP-ZnO) have been synthesized using sol-gel method. Nanostructural properties of aforementioned materials were studied by scanning electron microscope (SEM) and X-ray diffraction techniques. Williamson equation was used to estimate lattice strain in the PVP-ZnO nanocomposite. The dominated peaks in XRD spectra and Williamson- Hall diagrams were considered and the nano crystallite strain was plotted by drawing strain slopes. The obtained results showed that hybrid nanocomposites synthesized at 150ºC have lower strain and therefore higher yield strain. The SEM image indicated that nanoparticles are distributed uniformly. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 15 v. 3 no. 2019 279 282 https://ijpr.iut.ac.ir/article_1147_8dfc554ab16a288c81b2c8c8ed9cfa58.pdf dx.doi.org/10.18869/acadpub.ijpr.15.3.279 Study of the coherent propagation of charged leptons coming from pion and W decay in Bohmian mechanics H Azizakram گروه فیزیک، دانشکده علوم پایه، دانشگاه قم، قم author M M Ettefaghi گروه فیزیک، دانشکده علوم پایه، دانشگاه قم، قم author S V Mousavi گروه فیزیک، دانشکده علوم پایه، دانشگاه قم، قم author text article 2019 per Although charged leptons, contrary to neutrinos, cannot oscillate, exploring whether a coherent  superposition of charged lepton states can change to others during the propagation is an important problem in the neutrino oscillation theory. In this paper, we consider electrons and muons coming from the pions and W decays and study their propagation in relativistic Bohmian quantum mechanics. We find out that the Bohmian trajectories of them are separated after atomic distance propagations. In fact, the computed Bohmian trajectories of electrons and muons coming from W and pion decays show that Bohmin results are consistent with those of standard quantum mechanics. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 15 v. 3 no. 2019 283 289 https://ijpr.iut.ac.ir/article_1148_862c8977a6f1faf8ea6be36a8189da4a.pdf dx.doi.org/10.18869/acadpub.ijpr.15.3.283 Ab-initio study of Ag-chain adsorbed on graphene sheet H Salehi گروه فیزیک، دانشکده علوم، دانشگاه شهید چمران اهواز author M Moaddeli گروه فیزیک، دانشکده علوم، دانشگاه شهید چمران اهواز author P Amiri گروه فیزیک، دانشکده علوم، دانشگاه شهید چمران اهواز author text article 2019 per In this paper, the long-range Van Der Walls dispersion force correction (vdW-DF) for a combined system consisting of an Ag-chain adsorbed on a monolayer of graphene is studied. Calculations are based on density functional theory (DFT) performed by using various LDA, PBE and BLYP approximations. Since Ag chain is weakly adsorbed on graphene sheet, the Van Der Waals contribution to the total adsorption energy cannot be ignored. When applying this correction, the structural and electronic properties of the combined system such as adsorption energy, adsorption distance, and the Fermi level shift with respect to the Dirac point are significantly affected. The weak hybridization of the electronic states of silver and carbon at the interface gives rise to a small band gap opening at the Dirac point. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 15 v. 3 no. 2019 291 298 https://ijpr.iut.ac.ir/article_1149_20cc1cc54aeed8aed7f80b166ca5bf51.pdf dx.doi.org/10.18869/acadpub.ijpr.15.3.291 Effects of finite size on tera Hertz radiation of a superconductor media M Hosseini دانشکده فیزیک، دانشگاه صنعتی شیراز author text article 2019 per The Tera hertz radiation from a finite size superconductor media inside a magnetic field has been investigated. The tera hertz radiation is due to the flux flow motion inside the media. The electromagnetic fields inside the superconductor due to fluxons are calculated and using those fields, the radiation is obtained. In this research, the effects of finite size on the radiated power and signal mean width are investigated. The results show that by increasing the superconductor thickness, the peak values of harmonics increase and the mean width decreases. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 15 v. 3 no. 2019 299 303 https://ijpr.iut.ac.ir/article_1150_1e81ea6c2c3b4c6f4f3d434913d8c018.pdf dx.doi.org/10.18869/acadpub.ijpr.15.3.299 Mammographic image enhancement using wavelet transform and homomorphic filter F Majidi دانشگاه آزاد اسلامی، واحد علوم وتحقیقات یزد، دانشکده فنی و‌ مهندسی، یزد author A M Latif دانشکده برق و کامپیوتر، دانشگاه یزد author J Malakouti دانشکده پرستاری و مامایی، دانشگاه علوم پزشکی تبریز author H Kasayi پژوهشکده مواد، پژوهشگاه علوم و فنون هسته‌ای، سازمان انرژی اتمی author text article 2019 per Mammography is the most effective method for the early diagnosis of breast cancer diseases. As mammographic images contain low signal to noise ratio and low contrast, it becomes too difficult for radiologists to analyze mammogram. To deal with the above stated problems, it is very important to enhance the mammographic images using image processing methods. This paper introduces a new image enhancement approach for mammographic images which uses the modified mathematical morphology, wavelet transform and homomorphic filter to suppress the noise of images. For performance evaluation of the proposed method, contrast improvement index (CII) and edge preservation index (EPI) are adopted. Experimental results on mammographic images from Pejvak Digital Imaging Center (PDIC) show that the proposed algorithm improves the two indexes, thereby achieving the goal of enhancing mammographic images. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 15 v. 3 no. 2019 305 310 https://ijpr.iut.ac.ir/article_1151_e38f50bdd066925eec3bb80fb853afae.pdf dx.doi.org/10.18869/acadpub.ijpr.15.3.305 Effect of increasing length on the electronic transport of an armchair graphene nano-ribbons Sh Aghamiri Esfahani دانشکده فیزیک، دانشگاه خیام مشهد author M Sedaghatnia دانشکده فیزیک، دانشگاه خیام مشهد author text article 2019 per In this research, we have investigated the effect of increasing length on the electronic transport of an armchair graphene nano-ribbons with nitrogen atom impurity and without impurity. The semi-infinite, one-dimensional molecular systems are connected to two electrodes and the electron-electron interaction is ignored. The system is described by a simple tight binding model. All calculations are based on the Green&#39s function and Landauer–Buttiker approach, and the electrodes are described in a wide band approximation. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 15 v. 3 no. 2019 311 315 https://ijpr.iut.ac.ir/article_1152_5ddd047ad4d3457394c65f2021c86121.pdf dx.doi.org/10.18869/acadpub.ijpr.15.3.311 Tripartite entanglement of bosonic systems in a noninertial frame beyond the single- mode approximation M Soltani گروه فیزیک، دانشگاه اصفهان، اصفهان author A Javaheri گروه فیزیک، دانشگاه اصفهان، اصفهان author M Hadi گروه فیزیک، دانشگاه اصفهان، اصفهان author text article 2019 per In this work, we generalize the entanglement of three-qbit Bosonic systems beyond the single-mode approximation when one of the observers is accelerated. For this purpose, we review the effects of acceleration on field modes and quantum states. The single-mode approximation and beyond the single-mode approximation methods are introduced. After this brief introduction, the main problem of this paper, tripartite entanglement of bosonic systems in a noninertial frame beyond the single- mode approximation is investigated. The tripartite entangled states have different classes with GHZ and W states being most important. Here, we choose &pi-tangle as a measure of tripartite entanglement. If the three parties share GHZ state, the corresponding &pi-tangle will increase by increasing acceleration for some Unruh modes. This phenomenon, increasing entanglement, has never been observed in the single-mode approximation for bosonic case. Moreover, the &pi-tangle dose not exhibit a monotonic behavior with increasing acceleration. In the infinite acceleration limit, the &pi-tangle goes to different nonzero values for distinct Unruh modes. Unlike GHZ state, the entanglement of the W state shows only monotonically increasing and decreasing behaviors with increasing acceleration. Also, the entanglement for all possible choices of Unruh modes approaches only 0.176 in the high acceleration limit. Therefore, according to the quantum entanglement, there is no distinction between the single-mode approximation and beyond the single-mode approximation methods in this limit. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 15 v. 3 no. 2019 317 335 https://ijpr.iut.ac.ir/article_1153_335e7102a00b099695f7c5fbfceb2a0a.pdf dx.doi.org/10.18869/acadpub.ijpr.15.3.317 An investigation into crystalline phases and nano structural and mechanical properties of HH heat resistant stainless steels M Hosseini 1. گروه فیزیک، دانشگاه آزاد اسلامی واحد شهرضا author A Bahari 2. گروه فیزیک، دانشگاه بابلسر، مازندران author F Ahmadian 2. گروه فیزیک، دانشگاه بابلسر، مازندران author text article 2019 per In the present work, the effects of different casting parameters including pouring temperature and cooling rate on stainless steel structures and mechanical properties of heat resistant alloy (HH) were studied. Mo nanoparticles were synthesized through sol-gel method and were coated on the stainless steel device using spin-coating method. The effect of coating layer on the device was studied by using XRD (X-Ray Diffraction) and FT-IR (Fourier Transform Infra red ) and SEM (Scanning Electron Microscopy) techniques. The obtained results indicated an enhancement of corrosion, surface abrasion protection without changing metal surface structure, and a reduction of leakage current through the stainless steel device. Furthermore, pouring temperature and cooling rate increase caused a fine grain structure to be acquired with less carbides and better distribution in the austenitic matrix. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 15 v. 3 no. 2019 337 341 https://ijpr.iut.ac.ir/article_1154_2c93578203ae87c912e330da00579a1a.pdf dx.doi.org/10.18869/acadpub.ijpr.15.3.337 Investigation of the non-linear magnetic reconnection in solar chromosphere Z Fazel گروه فیزیک نظری و اخترفیزیک، دانشکده فیزیک، دانشگاه تبریز author text article 2019 per In order to see the occurrence of magnetic reconnection in the solar chromosphere, we investigate the behavior of non-linear perturbations on the magneto hydro dynamic (MHD) equations. Numericalstudy of the resistive tearing instability in a current sheet is presented by considering the MHD framework.To do this, the four field model is applied. It is shown based on the simulation that the non-linear terms make the reconnection occur faster during the spicule life time in the chromosphere. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 15 v. 3 no. 2019 343 343 https://ijpr.iut.ac.ir/article_1155_a4383c27ab888306c1b628f70ca0a7e4.pdf dx.doi.org/10.18869/acadpub.ijpr.15.3.343 Interaction between F2 gas with the pristine and 3C-doped(4, 4) armchair boron phosphide nanotubes: a DFT study M Rezaei-Sameti گروه شیمی فیزیک، دانشکده علوم پایه، دانشگاه ملایر author E A Dadfar گروه شیمی فیزیک، دانشکده علوم پایه، دانشگاه ملایر author text article 2019 per In this research, the structure, quantum and NQR (Nuclear quadrupole resonance)parameters of F2 gas adsorption on the pristine and 3C-doped (4,4) armchair models of boron phosphide nanotubes (BPNTs) have been investigated in the framework of density functional theory. For this purpose, at the first step, four models for F2 adsorption on the inner and outer surfaces of pristine and 3C-doped BPNTS are considered and then all structures are optimized by using Gaussian 03 program package. The optimized structures are used to calculate the quantum and NQR parameters. The calculated results reveal that the adsorption energy of pristine and 3C-doped models of BPNTs are exothermic and adsorption process is a physisorption process due to the weak Van der Waals interaction. The substitution of three carbons with three B atoms of nanotube decreases significantly the adsorption energies. The F2 adsorption and 3C-doping decrease the band gap, global hardness, and ionization potential of the pristine BPNTs. The calculated NQR parameters of all the models show that CQ and &etaQ values of the first layer are larger than those of the other layers. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 15 v. 3 no. 2019 344 344 https://ijpr.iut.ac.ir/article_1156_552363a42d70adf5f4bcec0b982695c4.pdf dx.doi.org/10.18869/acadpub.ijpr.15.3.344 Ultra-fast spectroscopy investigation of Verwey transition in magnetite A Mokhtari گروه فیزیک، دانشگاه آزاد اسلامی واحد اراک author J R Neal گروه فیزیک وستاره‌شناسی، دانشگاه شفیلد انگستان author H J Blythe گروه فیزیک وستاره‌شناسی، دانشگاه شفیلد انگستان author G A Gehring گروه فیزیک وستاره‌شناسی، دانشگاه شفیلد انگستان author text article 2019 per Magnetite has a different electrical resistance behavior with temperatures below and above the Verwey temperature. Here, we report on Verwey transition in Fe3O4 by means of the frequency-doubled output from the Ti-sapphire laser in pump-probe experiments and from the insulator to metal transition observed by changing the temperature at the wavelength 370nm (~3.36 eV) both for pump and probe. We observed a clear difference below and above the Verwey temperature in ultra-fast transmission changes. Iranian Journal of Physics Research Isfahan University of Technology, The Physics Society of Iran 1682-6957 15 v. 3 no. 2019 345 345 https://ijpr.iut.ac.ir/article_1157_95b64e976019d4d8d5afb89efe6ac190.pdf dx.doi.org/10.18869/acadpub.ijpr.15.3.345