Journal of Theoretical and Applied Physics (JTAP) Mitigation of disruption on IR-T1 tokamak by means of low-energy neutral beam injection to control runaway electron generation Volume 14 (2020) Issue 4, August 2020 2023 11 17 Mitigation of disruption on IR-T1 tokamak by means of low-energy neutral beam injection to control runaway electron generation 10.1007/s40094-020-00386-1 EN M. Kafi Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran Mahmoud Ghoranneviss Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, Tehran, Iran Mohammad Reza Ghanbari Department of Basic Sciences, Garmsar Branch, Islamic Azad University, Garmsar, Iran Mohammad Kazem Salem Plasma Physics Research Center, Science and Research Branch, Islamic Azad University, P.O. Box: 14665‑678, Tehran, Iran 0000-0002-8810-1820 Journal Article 2023 11 17 AbstractIn a tokamak, the poloidal magnetic field provided by the toroidal plasma current forms an essential part of the magnetic field confining the plasma. However, instabilities of magnetohydrodynamic equilibrium can lead to an uncontrolled sudden loss of plasma current and energy, which is called a disruption. Disruptions are of significant concern to future devices due to the large amount of energy released during the rapid quenching of the plasma. One important consequence of disruption is the generation of significant current carried in multi-MeV runaway electrons that are eventually lost into plasma components. They can damage the tokamak walls and its structure if they are not controlled. Disruption control by neutral beam injection has been performed on IR-T1 to study the effect on runaway electron generated by plasma disruptions. Noble gases are used for injection, pure Hydrogen, Helium and Argon. The use of these non-reactive gases for disruption control ensures they fast removed from the vessel after the termination of a tokamak discharge. A piezo-valve is used for injection which has the precision of 1 ms. The effect of runaway electron generation control during disruption is studied using a comparison between reference disruptive discharge and a discharge into which different impurity species are injected. The data collected can then be used to optimize the performance of these energetic electrons control generated in disruption.

Journal of Theoretical and Applied Physics (JTAP) Enhancement of charge breeding efficiency for rare isotope beam with the control of magnetic field profile and electron beam energy in EBIS Volume 14 (2020) Issue 4, August 2020 2023 11 17 Enhancement of charge breeding efficiency for rare isotope beam with the control of magnetic field profile and electron beam energy in EBIS 10.1007/s40094-020-00388-z EN Jong-Won Kim Rare Isotope Science Project, Institute for Basic Science, Daejeon 34000, Korea 0000-0003-3052-8482 Journal Article 2023 11 17 AbstractThe magnetic field in the ion trap of electron beam ion source (EBIS) determines the current density of electron beam and thus the depth of trap potential, which affects the charge breeding efficiency to desired charge state. An EBIS charge breeder has been constructed to be used for the Rare Isotope Science Project in Korea. A 6 T superconducting solenoid is used for the trap, and uniform magnetic field is extended with correction coils at the ends. The effect of field uniformity on the electron current density is evaluated using TRAK, and it is shown sizable improvement in the charge breeding efficiency for rare isotope beams can be obtained by elaborate magnetic design. Furthermore, the electron beam energy affects the ionization efficiency. The electron energy is often reduced in the trap for optimal matching with charge striping cross section. However, virtual cathode formation can appear in the process of energy reduction. Maximum beam currents limited by electron energy are studied analytically and by TRAK simulation in the view of improving the charge breeding efficiency.

Journal of Theoretical and Applied Physics (JTAP) Transcriptional responses following seed priming with cold plasma and electromagnetic field in Salvia nemorosa L. Volume 14 (2020) Issue 4, August 2020 2023 11 17 Transcriptional responses following seed priming with cold plasma and electromagnetic field in Salvia nemorosa L. 10.1007/s40094-020-00387-0 EN Maryam Ghaemi Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran Ahmad Majd Department of Biology, Faculty of Biological Sciences, North-Tehran Branch, Islamic Azad University, Tehran, Iran Alireza Iranbakhsh Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran Journal Article 2023 11 17 AbstractThis study was conducted to monitor the plant responses to seed priming with electromagnetic fields (0, 4, or 6 mT) or cold plasma (0, 80, or 100 s) in Salvia nemorosa. The cold plasma or electromagnetic field treatments significantly increased shoot fresh weight (49%), root fresh weight (41%), and root length (56%). The results highlighted that seed priming with cold plasma or the electromagnetic field is an effective method to modify seedling growth. The electromagnetic field and plasma treatments upregulated the AREB1 gene (mean = 3.9-fold). Except for the electromagnetic field of 4mT, the other treatments stimulated expressions of the WRKY1 gene by an average of 6.7-fold relative to the control. The cold plasma or electromagnetic field also induced the expression of cinnamoyl-CoA reductases (CCR2) gene (mean = fourfold). These treatments also changed the expression of the rosmarinic acid synthase by an average of sixfold. These findings may improve our knowledge of plant reactions to cold plasma and electromagnetic field for possible functions in seed technology.

Journal of Theoretical and Applied Physics (JTAP) The effects of multiwall carbon nanotubes on the electrical characteristics of ZnO-based composites Volume 14 (2020) Issue 4, August 2020 2023 11 17 The effects of multiwall carbon nanotubes on the electrical characteristics of ZnO-based composites 10.1007/s40094-020-00389-y EN N. Asaadi Department of Condensed Matter Physics, Faculty of Physics, University of Tabriz, 29 Bahman Blvd., Imam St., Tabriz, Iran M. Parhizkar Department of Condensed Matter Physics, Faculty of Physics, University of Tabriz, 29 Bahman Blvd., Imam St., Tabriz, Iran 0000-0002-6847-6799 H. Bidadi Department of Condensed Matter Physics, Faculty of Physics, University of Tabriz, 29 Bahman Blvd., Imam St., Tabriz, Iran S. Mohammadi Aref Department of Condensed Matter Physics, Faculty of Physics, University of Tabriz, 29 Bahman Blvd., Imam St., Tabriz, Iran M. Ghafouri Department of Physics, Faculty of Physics, Shabestar Branch, Islamic Azad University, Shabestar, Iran Journal Article 2023 11 17 AbstractIn this experimental work, the effects of multiwall carbon nanotubes (MWCNTs) on electrical characteristics of zinc oxide–MWCNT–high-density polyethylene composite varistors have been investigated. All the samples were made at the temperature of 130 °C and pressure of 60 MPa by the hot-press method. Results show that increasing zinc oxide content in the mixture increases breakdown voltage up to 170 V, where the highest nonlinear coefficient (α ~ 13) corresponds to the samples with 95 wt% of ZnO. Results with regard to the effects of MWCNT as an additive reveal that increasing its content from 1 to 2.5% in the composites, the breakdown voltage decreases to 50 V, but the highest nonlinear coefficient (~ 14) corresponds to the sample with 1.5% of MWCNT content. It is also revealed that, heat treatment of the sample at a constant temperature of 135 °C and different time intervals from 2 to 10 h, the sample with 6 h annealing time shows maximum breakdown voltages (Vb = 140 V) with the highest nonlinear coefficient (~ 14). Investigation of the potential barrier height of samples shows a complete consistency with the breakdown voltage variations. The results have been justified regarding XRD patterns and SEM micrographs of samples.

Journal of Theoretical and Applied Physics (JTAP) Fabrication of Au/ZnO/MWCNTs electrode and its characterization for electrochemical cholesterol biosensor Volume 14 (2020) Issue 4, August 2020 2023 11 17 Fabrication of Au/ZnO/MWCNTs electrode and its characterization for electrochemical cholesterol biosensor 10.1007/s40094-020-00390-5 EN Davood Ghanei Agh Kaariz Department of Physics, Faculty of Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran Elham Darabi Department of Physics, Faculty of Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran 0000-0001-9887-5291 Seyed Mohammad Elahi Department of Physics, Faculty of Sciences, Science and Research Branch, Islamic Azad University, Tehran, Iran Journal Article 2023 11 17 AbstractIn this work, a new sensitive enzyme-based electrode for electrochemical cholesterol biosensor was fabricated based on a nanocomposite of Au nanoparticles, ZnO nanoparticles and multi-wall carbon nanotubes (Au/ZnO/MWCNTs). The nanocomposite was prepared by sol–gel method and deposited on FTO substrate by dip coating, followed by cholesterol oxidase (ChOx) enzyme immobilized (ChOx/Au/ZnO/MWCNTs). Structural properties and morphology of the nanocomposite have been studied using X-ray diffraction (XRD) and Field emission scanning electron microscopy (FESEM). The sample was subjected to Fourier transform infrared spectroscopy (FTIR) to determine functional groups. Electrochemical behavior of the electrode was studied by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) techniques as a function of cholesterol concentration. Electrochemical impedance spectroscopy (EIS) was also considered to study of surface modified electrodes. The ChOx/Au/ZnO/MWCNTs electrode has been found to have enhanced electron transfer and display excellent analytical linear performances. The fabricated electrode exhibited low detection limit (0.1 μM), high sensitivity (25.89 μA/μM) evaluated from DPV data in the detection range of 0.1–100 µM and high selectivity in the determination of cholesterol over glucose and uric acid. The application of the ChOx/Au/ZnO/MWCNTs electrode in detection of cholesterol in human serum was also confirmed.

Journal of Theoretical and Applied Physics (JTAP) Transmission of electromagnetic waves through a nonlinear over-dense plasma slab Volume 14 (2020) Issue 4, August 2020 2023 11 17 Transmission of electromagnetic waves through a nonlinear over-dense plasma slab 10.1007/s40094-020-00391-4 EN M. Tohfeh Department of Physics, North Tehran Branch, Islamic Azad University, Tehran, Iran Leila Rajaei Department of Physics, Faculty of Basic Sciences, University of Qom, Qom, Iran 0000-0002-1303-9225 Sedigheh Miraboutalebi Department of Physics, North Tehran Branch, Islamic Azad University, Tehran, Iran 0000-0002-3117-3938 L Farhang Matin Department of Physics, North Tehran Branch, Islamic Azad University, Tehran, Iran Journal Article 2023 11 17 AbstractA study on the transmission of the electromagnetic waves from a structure consisting of an over-dense plasma layer with nonlinear effects is undertaken. The applied nonlinearity is presented due to the series expansion of the polarization in the medium. The nonlinear plasma layer is supposed to be placed between two linear dielectric layers. The transparency conditions are investigated for the p-polarized obliquely incident waves. It is shown that the formation of the surface waves can eventuate to the transmission of the incident waves. This fact has already be seen in the case of the linear over-dense plasma, but, here, it is examined in the presence of the nonlinear effects. To determine the propitious conditions for the surface wave excitation, the exact solutions of the electromagnetic field equations are used in all regions. The transmission, the reflection, and the dissipation rates of the electromagnetic waves from the entire structure are obtained, and the effects of the main parameters on them are discussed.

Journal of Theoretical and Applied Physics (JTAP) Terahertz emission during laser-plasma interaction: effect of electron temperature and collisions Volume 14 (2020) Issue 4, August 2020 2023 11 17 Terahertz emission during laser-plasma interaction: effect of electron temperature and collisions 10.1007/s40094-020-00392-3 EN Hitendra K Malik Plasma Waves and Particle Acceleration Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi, India 0000-0002-9432-8140 Divya Singh Rajdhani College, Delhi University, Delhi, New Delhi, India Journal Article 2023 11 17 AbstractThe electron-neutral collisions in the plasma become crucial with regard to the generation of THz radiation when thermal motion of the electrons is considerable. If we look at the mechanism of THz emission, this is only the movement/oscillations of the electrons which is responsible for the excitation of nonlinear current that generated the THz radiation. The present work aims to disclose the role of thermal motion of the plasma electrons to the resonance condition and the THz emission when two co-propagating super-Gaussian laser beams beat in the plasma. The dynamics of the plasma electrons and subsequent generation of nonlinear current are discussed in greater detail for the emission of THz radiation.

Journal of Theoretical and Applied Physics (JTAP) Tunable and reversible thermo-plasmonic hot spot imaging for temperature confinement Volume 14 (2020) Issue 4, August 2020 2023 11 17 Tunable and reversible thermo-plasmonic hot spot imaging for temperature confinement 10.1007/s40094-020-00393-2 EN N. S. Shnan Magneto‑plasmonic Lab, Laser and Plasma Research Institute, Shahid Beheshti University, Tehran, Iran Department of Laser Physics, College of Science for Woman, University of Babylon, Babylon, Iraq N. Roostaei Magneto‑plasmonic Lab, Laser and Plasma Research Institute, Shahid Beheshti University, Tehran, Iran S. M. Hamidi Magneto‑plasmonic Lab, Laser and Plasma Research Institute, Shahid Beheshti University, Tehran, Iran 0000-0002-5298-2224 Journal Article 2023 11 17 AbstractIn the present study, a novel tunable two-dimensional thermo-plasmonic grating based on gold nanorods was demonstrated by combining the plasmonic properties of the gold nanostructure and the applied external voltage. In this structure, a thin layer of the gold grating was typically deposited on a patterned polydimethylsiloxane substrate using the nanoimprint lithography method. The surface plasmon resonance of the fabricated plasmonic structure was excited by the surface plasmon imaging system based on a high numerical aperture objective lens and the charged coupled device camera. Based on the results, the number of the plasmonic hot spots due to the thermo-plasmonic effect increased by the external voltage, leading to an increase in this effect. Therefore, this reversible and tunable temperature confinement can be used as the controller of each element including cells in a defined micro-position.

Journal of Theoretical and Applied Physics (JTAP) Comparative study of behavior of electrical conductivity in KI‒Al2O3 and KI‒TiO2 heterostructure composites Volume 14 (2020) Issue 4, August 2020 2023 11 17 Comparative study of behavior of electrical conductivity in KI‒Al2O3 and KI‒TiO2 heterostructure composites 10.1007/s40094-020-00394-1 EN Suhail Iqbal Wani Physical Chemistry Division, Department of Chemistry, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India Nazli Zeeshan Physical Chemistry Division, Department of Chemistry, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India Rafiuddin Physical Chemistry Division, Department of Chemistry, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India Journal Article 2023 11 17 AbstractThe present work reports development of binary KI–Al2O3 and KI–TiO2-based nanocomposites using simple solid-state reaction method and is characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy and impedance spectroscopy. The results show the effect of heterogeneously doped Al2O3 and TiO2 on the ionic conductivity of pure KI which is moderately conductive. The results supported the composite development in which the interface layer portrays a significant part in governing the bulk properties of the compound. Improvement in electrical conductivity is seen in the incorporation of Al2O3 and TiO2 dispersoid into the matrix of KI. With temperature, electrical conductivity increased and the activation energies were found to be decreasing. The activation energies for KI–Al2O3 and KI–TiO2 systems were 0.22 eV and 0.21 eV, respectively, in the temperature range 20‒400 °C. Dielectric constant increases with the increase in temperature in the entire temperature range studied attributed to the phenomenon of distortion of electric charges.

Journal of Theoretical and Applied Physics (JTAP) The effects of grounded electrode geometry on RF-driven cold atmospheric pressure plasma micro-jet Volume 14 (2020) Issue 4, August 2020 2023 11 17 The effects of grounded electrode geometry on RF-driven cold atmospheric pressure plasma micro-jet 10.1007/s40094-020-00395-0 EN Davood Hassanpour Advanced Plasma Laboratory, Faculty of Physics, University of Tabriz, Tabriz, Iran 0000-0003-1010-2775 Sayyed‑Jalal Pestehe Advanced Plasma Laboratory, Faculty of Physics, University of Tabriz, Tabriz, Iran 0000-0003-3224-4600 Journal Article 2023 11 17 AbstractWith the argument that two-electrode DBD-like systems are much more operational than single-electrode systems in biomedical applications, targets sensitive to temperature and electric shock, the effects of parameters associated with the geometry of the grounded electrode such as its shape, size, and position it at the output of the atmospheric pressure RF plasma jet in two-electrode systems is investigated. By varying the position of the typical narrow ring grounded electrode on the dielectric tube toward the powered electrode, the ratio of the axial to radial electric field components depend on the externally applied potential to the plasma has been investigated and shown that the axial component of the electric field is maximized at certain position(s) of the grounded electrode. The analysis of the data indicates that there is an inverse relationship between the magnitude of the axial electric field in the plasma channel and the discharge ignition voltage, and a direct relationship with the plasma jet length. It is known that by increasing the width of the ground electrode until the full covering of dielectric, the jet length increases from the dielectric output to the neighborhood near the needle electrode, and reduces the discharge ignition threshold and consequently power consumption of the jet, but increasing its width to greater than the above values does not have a significant effect on jet output. It has also been shown that by tapering the dielectric end and fully covering it with its conical-shaped electrode, the output jet length increases and decreases its width.

Journal of Theoretical and Applied Physics (JTAP) Industrial application of apodized gas sensor for on-line and in situ measurement of CO and CO2 concentration Volume 14 (2020) Issue 4, August 2020 2023 11 17 Industrial application of apodized gas sensor for on-line and in situ measurement of CO and CO2 concentration 10.1007/s40094-020-00396-z EN Alireza Khorsandi Department of Physics, University of Isfahan, Isfahan 81746‑73441, Iran 0000-0002-9086-718X Saeed Ghavami Sabouri Department of Physics, University of Isfahan, Isfahan 81746‑73441, Iran 0000-0002-6200-4459 Journal Article 2023 11 17 AbstractThe performance of an apodized gas sensor is demonstrated through simultaneous detection of CO and CO2 absorption lines around 1.57 µm in the recuperator channel of a gas-fired industrial furnace at Shahid Montazeri power plant (SMPP) industry. This led to the concentration measurement of targeted molecules as less than ~ 1% and 9.5%, respectively, at atmospheric pressure and 350 °C, indicating close consistency with the reference data reported by SMPP. A minimum detectable absorption of ~ 0.4 × 10−3, corresponding to a detection sensitivity of ~ 4.8 × 10−9 cm−1 Hz−1/2 is measured in this application.