Puckered Penta-like PdPX (X = O, S, Te) Semiconducting Nanosheets: First-Principles Study of the Mechanical, Electro-Optical, and Photocatalytic Properties.

The atomic, electronic, optical, and mechanical properties of penta-like two-dimensional PdPX (X = O, S, Te) nanosheets have been systematically investigated using density functional theory calculations. All three PdPX nanosheets exhibit dynamic and mechanical stability on the basis of an analysis of phonon dispersions and the Born criteria, respectively. The PdPX monolayers are found to be brittle structures.

First-principles investigation of electronic, mechanical and thermoelectric properties of graphene-like XBi (X = Si, Ge, Sn) monolayers.

Research progress on single layer group III monochalcogenides has been increasing rapidly owing to their interesting physics. Herein, we investigate the dynamically stable single layer forms of XBi (X = Ge, Si or Sn) using density functional theory calculations. Phonon band dispersion calculations and ab initio molecular dynamics simulations reveal the dynamical and thermal stability of the considered monolayers.

Semiconducting Chalcogenide Alloys Based on the (Ge, Sn, Pb) (S, Se, Te) Formula with Outstanding Properties: A First-Principles Calculation Study.

Very recently, a new class of the multicationic and -anionic entropy-stabilized chalcogenide alloys based on the (Ge, Sn, Pb) (S, Se, Te) formula has been successfully fabricated and characterized experimentally [Zihao Deng , 6070 ()]. Motivated by the recent experiment, herein, we perform density functional theory-based first-principles calculations in order to investigate the structural, mechanical, electronic, optical, and thermoelectric properties. The calculations of the cohesive energy and elasticity parameters indicate that the alloy is stable.

Electronic and optical properties of two-dimensional heterostructures and heterojunctions between doped-graphene and C- and N-containing materials.

The electronic and optical properties of vertical heterostructures (HTSs) and lateral heterojunctions (HTJs) between (B,N)-codoped graphene (dop@Gr) and graphene (Gr), CN, BC and h-BN monolayers are investigated using van der Waals density functional theory calculations. We have found that all the considered HTSs are energetically and thermally feasible at room temperature, and therefore they can be synthesized experimentally. The dop@Gr/Gr, BC/dop@Gr and BN/dop@Gr HTSs are semiconductors with direct bandgaps of 0.

Tunable electronic properties of the dynamically stable layered mineral PtHgSe (Jacutingaite).

Density functional theory calculations are performed in order to study the structural and electronic properties of monolayer PtHgSe. Our results show that the dynamically stable monolayer PtHgSe is a topological insulator with a band gap of 160 meV. In addition, the effect of layer thickness, strain and electric field on the electronic properties are systematically investigated using fully relativistic calculations.

Two-dimensional silicon bismotide (SiBi) monolayer with a honeycomb-like lattice: first-principles study of tuning the electronic properties.

Using density functional theory, we investigate a novel two-dimensional silicon bismotide (SiBi) that has a layered GaSe-like crystal structure. molecular dynamic simulations and phonon dispersion calculations suggest its good thermal and dynamical stability. The SiBi monolayer is a semiconductor with a narrow indirect bandgap of 0.

Correction: The mechanical, electronic, optical and thermoelectric properties of two-dimensional honeycomb-like of XSb (X = Si, Ge, Sn) monolayers: a first-principles calculations.

[This corrects the article DOI: 10.1039/D0RA05587E.].

The mechanical, electronic, optical and thermoelectric properties of two-dimensional honeycomb-like of XSb (X = Si, Ge, Sn) monolayers: a first-principles calculations.

Herein, by using first-principles calculations, we demonstrate a two-dimensional (2D) of XSb (X = Si, Ge, and Sn) monolayers that have a honey-like crystal structure. The structural, mechanical, electronic, thermoelectric efficiency, and optical properties of XSb monolayers are studied. molecular dynamic simulations and phonon dispersion calculations suggests their good thermal and dynamical stabilities.

Investigation of strain and doping on the electronic properties of single layers of CN and CN: a first principles study.

In this work, by performing first-principles calculations, we explore the effects of various atom impurities on the electronic and magnetic properties of single layers of CN and CN. Our results indicate that atom doping may significantly modify the electronic properties. Surprisingly, doping Cr into a holey site of CN monolayer was found to exhibit a narrow band gap of 125 meV upon compression strain, considering the spin-orbit coupling effect.

Embedding of atoms into the nanopore sites of the CN and CN porous carbon nitride monolayers with tunable electronic properties.

Using first-principles calculations, we study the effect of embedding various atoms into the nanopore sites of both C6N6 and C6N8 monolayers. Our results indicate that the embedded atoms significantly affect the electronic and magnetic properties of C6N6 and C6N8 monolayers and lead to extraordinary and multifarious electronic properties, such as metallic, half-metallic, spin-glass semiconductor and dilute-magnetic semiconductor behaviour. Our results reveal that the H atom concentration dramatically affects the C6N6 monolayer.

Control of CN and CN carbon nitride nanosheets' electronic and magnetic properties through embedded atoms.

In the present work, the effect of various embedded atom impurities on tuning electronic and magnetic properties of CN and CN nanosheets have been studied using first-principles calculations. Our calculations show that CN is a semiconductor and it exhibits extraordinary electronic properties such as dilute-magnetic semiconductor (with H, F, Cl, Be, V, Fe and Co); metal (with N, P, Mg and Ca), half-metal (with Li, Na, K, Al, Sc, Cr, Mn, and Cu) and semiconductor (with O, S, B, C, Si, Ti, Ni and Zn) with the band gaps in the range of 0.3-2.

The automatic frequency control based on artificial intelligence for compact particle accelerator.

In this work, an advantage actor critic (A2C) based intelligent automatic frequency control (AFC) system was developed for X-band linear accelerator (LINAC). A2C is one type of reinforcement learning, which indicates how software agents should perform actions in an environment. In this paper, the A2C based AFC algorithm and its environment design, simulation result, and controller hardware and software processes are described.

Tuning the electronic and magnetic properties of antimonene nanosheets via point defects and external fields: first-principles calculations.

Defects are inevitably present in materials, and their existence in a material strongly affects its fundamental physical properties. We have systematically investigated the effects of surface adsorption, substitutional impurities, defect engineering, an electric field and strain engineering on the structural, electronic and magnetic properties of antimonene nanosheets, using spin-polarized density functional calculations based on first-principles. The adsorption or substitution of atoms can locally modify the atomic and electronic structures as well as induce a variety of electronic behaviors including metal, half-metal, ferromagnetic metal, dilute magnetic semiconductor and spin-glass semiconductor.

Development of a disposable kit with fully automatic self-shielding reactor for [F]FDG synthesis.

A self-shielding device for the synthesis of radiopharmaceuticals was developed and fabricated in this study. Radiation exposure was minimized by the self-shielding of the kit, installation of the disposable kit in the auxiliary chamber while in a shielded state, and discharge of the kit into a radioactive waste container upon completion of the synthesis process. The developed self-shielding synthesis kit was tested by synthesizing 2-[F]fluoro-2-deoxy-D-glucose ([F]FDG) in order to verify its performance.

Development of an 83.2 MHz, 3.2 kW solid-state RF amplifier using Wilkinson power divider and combiner for a 10 MeV cyclotron.

We design a stripline-type Wilkinson power divider and combiner for a 3.2 kW solid-state radio frequency (RF) amplifier module and optimize this setup. A Teflon-based printed circuit board is used in the power combiner to transmit high RF power efficiently in the limited space.

Estimation of photoneutron yield in linear accelerator with different collimation systems by Geant4 and MCNPX simulation codes.

At present, the bremsstrahlung photon beams produced by linear accelerators are the most commonly employed method of radiotherapy for tumor treatments. A photoneutron source based on three different energies (6, 10 and 15 MeV) of a linac electron beam was designed by means of Geant4 and Monte Carlo N-Particle eXtended (MCNPX) simulation codes. To obtain maximum neutron yield, two arrangements for the photo neutron convertor were studied: (a) without a collimator, and (b) placement of the convertor after the collimator.

Proton beam dosimetry: a comparison between a plastic scintillator, ionization chamber and Faraday cup.

In this study, a comparison was made between a plastic scintillator (BC400), a Faraday Cup (FC) and an ionization chamber (IC) used for routine proton dosimetry. Thin scintillators can be applied to proton dosimetry and consequently to proton therapy as relative dosimeters because of their water-equivalent nature, high energy-light conversion efficiency, low dimensions and good proportionality to the absorbed dose at low stopping powers. To employ such scintillators as relative dosimeters in proton therapy, the corrective factors must be applied to correct the quenching luminescence at the Bragg peak.