Showing 3 results for Miran
A. Namiranian , M. Kalantar,
Volume 8, Issue 3 (september 2011 2011)
Abstract
The process of mullitization of kyanite concentrate was studied at different conditions of heat treatment (1400
– 1600 °C and 0.5 – 3.5 hours) and particle size of raw materials (38-300 ?m). Kyanite concentrate was obtained from
ore-dressing of kyanite deposits of Mishidowan-Bafgh region at 100 km northeastern part of Yazd. The results of
microstructure (shape, distribution and size of the grains) and phase evolution studies by SEM and XRD showed that
total transformation of kyanite to mullite takes place by heat treatment between 1500 –1550 °C during 2.5 hours.. At
temperatures below 1500 °C need-like mullite grains are always produced. At higher temperatures the mullite grains
reveal rounded and platelet morphology. At 1550 °C, the rate of mullitization and densification were improved by
increasing soaking time from 1h to 3h and decreasing particle size of materials from 300 to 38 m
Hussein Ali Jan Miran, Zainab Naji Abdullah, Mohammednoor Altarawneh, M Mahbubur Rahman, Auday Tariq Al-Bayati, Ebtisam M-T. Salman,
Volume 20, Issue 1 (March 2023)
Abstract
This contribution evaluates the influence of Cr doping on the ground state properties of SrTiO3 Perovskite using GGA-PBE approximation. Results of the simulated model infer agreement with the previously published literature. The modification of electronic structure and optical properties due to Cr3+ doping levels in SrTiO3 has been investigated. Structural parameters infer that Cr3+ doping alters the electronic structures of SrTiO3 by shifting the conduction band through lower energies for the Sr and Ti sites. Substituting Ti site by Cr3+ results the energy gap in being eliminated revealing a new electrical case of conducting material for the system. Furthermore, it has been noticed that Cr doping either at Sr or Ti positions could effectively develop the SrTiO3 dielectric constant properties. Consequently, Cr3+ is an effective dopant due to enhancing the optical absorption properties, thus opening up new prospects for optoelectronic applications.
Noor Alhuda Hassan, Zainab Jaf, Hanaa Ibrahem, Mohammed Hamid, Hussein Miran,
Volume 21, Issue 0 (IN PRESS 2024)
Abstract
This work reports the influence of Cu dopant and annealing temperature on CdOx thin films deposited on glass substrates by spray-pyrolysis method. The Cu doping concentrations were 0, 0.46, and 1.51 at% with respect to the CdOx undoped material. Then, the fabricated films were subjected to annealing process at temperature of 450°C. X-ray diffraction (XRD) examination confirms that the as-deposited films show a cubic crystallographic structure with high purity of CdO in the annealed films. It was found that the (111) peak is the most predominant diffraction orientation in the surveyed samples. At the microscopic scale, AFM machine was operated to quantify the three important parameters of the mean roughness (Ra), rms value (Rq), and z scale. These parameters hold highest values for the sample with 0.46 at% of Cu. Finally, reflectance, absorbance, transmittance and other optical parameters dielectric measurements were comprehensively analyzed. Our evaluation of optical band gaps for the studied samples reveals that the synthesized films have direct band gap character with the fact that the rise in the Cu contents in the as-deposited films lead to lessen the band gap values. In contrast, annealing process results in raising the band gap.
