Biography:

Bhim Kafle, (Ph.D. in physics), now is an Assistant professor of physical chemistry at Kathmandu University (KU), head of the Material Science Research Laboratory(MSRL,KU) and a life Member of the Chemical Society of Nepal. He got his B Sc (with physics, chemistry and math as majors), M Sc in Physical Chemistry (Tribhuvan University, Nepal) and also in Solar Energy and Environmental Science (Ben-Gurion University, Israel), Specialist in photochemistry, Doctor's degree (Ph.D.) at Graduate University for Advanced Studies (GUAS, Japan), got “The World Academy of Science (TWAS)” Award in 2012, and a best poster presentation Award from “Electrostatic Storage Devices Workshop (ESD-2011)”, US, 2011. Currently Dr. Kafle’s researches focus on the Spectroscopy of sensitizers for dye sensitized and perovskite solar cells and thin film preparation techniques.

Abstract:

In this study, dependence of optical and electrical properties of FTO thin transparent film on calcination conditions (thermal treatment in an oven in aerobic and anaerobic conditions, specifically, in the presence of either air or N₂ gas) were studied. The FTO films were fabricated with low cost home-made spray pyrolysis setup and calcinated at 500 ^oC for two different environments for thirty minutes. The homogeneous solution of stannous chloride (Sncl₂.2H₂O) and ammonium fluoride (NH₄F) in distilled water was used as a precursor solution. The films’ structural, surface, optical and electrical properties were measured with XRD, SEM, UV-Vis spectroscopy, and 2-Probe measurements, respectively. The FTO films fabricated by spraying the precursor solution for 30 minutes with F to Sn to ratio of 0.85:1.81 and calcined in the presence of air followed by low temperature plasma treatment yielded the lowest electrical resistance of 17 Ωcm^-1 and maximum transmittance of ca. 80 %. Also, the effect of calcination environment and plasma treatment on film’s reflectance will also be discussed.  

Biography:

 

Tohid Saeid is a Faculty of Materials Engineering of Sahand University of Technology .

Abstract:

Friction stir welding (FSW) was conducted on a SAF 2205 duplex stainless steel at welding speed of 50 mm/min and rotational speed of 400 rpm.  Characterization of evolved material was studied using electron microscopy equipped with electron back scattered diffraction (EBSD) system. The results indicated that the severe plastic deformation and the heat generated during the FSW process developed a very fine microstructure in the stir zone (SZ) of the weldment. It was found that the finest grains with average grain size of 1 µm were formed in the bottom of the SZ where the material was more likely to receive the lowest temperature in both constituent phases of ferrite and austenite. The presence of such severe deformation along with the elevated temperature during the welding procedure inside the SZ activates the occurrence of continuous dynamic recrystallization mechanism throughout the material which seems to be responsible for grain refinement. Moreover, Texture analysis showed that the rotating tool broke the initial microstructure, modified the pre-existence rolling texture of the starting material, and introduced simple shear texture components into the SZ. This kind of modification mainly took place by activation of the {111}<110> and {110}<111> easy slip systems of austenite and ferrite, respectively.

 

Biography:

Mohana F. Attia is a Sudanese academic researcher. Attia obtained a B.Sc. in applied physics and mathematics at Omdurman Ahlia University and a M.Sc. in applied physics at Dongola University. Now about to complete his PhD from Al– Neelain University, Sudan. He has many articles and two books and has been lectured at many Universities and Research Centers in (Sudan, KSA). Since 2017, he is lecturer of Alasala Colleges, KSA.

Abstract:

The purpose of this paper is to investigate the structural and optical characteristics of a doped in ZnO nanoparticles. Part of the aim is to study the characterization of chalcone doped ZnO nanoparticles by several techniques such as X-ray diffraction, Scanning electron microscope, FTIR spectroscopy and diffuse reflection spectra.  All doped samples showed hexagonal wurtzite structure. This study has shown that, the crystallite size of pure ZnO varied from 23.50 to 27.45 nm and when, increasing the chalcone percentage by 1 and 1.5% has increased the crystallite sizes in the range of 33.40–33.80 nm and 33.80–36.20 nm, respectively. The value of the energy gap (Eg) for ZnO nanoparticles was 3.14 eV. For 1 and 1.5% chalcone doped ZnO, the energy gap decreased by an order of magnitude 0.18 eV. The vibration band of ZnO at 435 cm −1 was shifted to the higher wave number of 442 and 447 cm −1 for the dopant 1 and 1.5%, respectively.  

Biography:

Yahia CHERGUI is a lecturer in Electrical & Electronics Engineering Institute, Boumerdes Algeria. He has completed his PhD from Badji Mokhtar University in Annaba, Algeria. He did all his  PhD work in Cardiff University in UK. His research field is Physics(condensed matter, simulation by molecular dynamics). He is  a lecturer in Boumerdes University( Electrical & Electronics Engineering Institute) since 2012. He has many published articles and international conferences. He has been serving as a referee with condensed matter journal (IOP), Energy journal (Elsevier), and recently accepted to be a reviewer of American Journal of Modern Physics. He is an academic member of the Athens Institute for Education and Research belonging to Physics Unit.

 

Abstract: