Thin a-:H films were grown successfully by fabrication of designated ingot followed by evaporation onto glass slides. A range of growth conditions, Ge contents, dopant concentration (Al and As), and substrate temperature, were employed. Stoichiometry of the thin films composition was confirmed using standard surface techniques. The structure of all films was amorphous. Film composition and deposition parameters were investigated for their bearing on film electrical and optical properties. More than one transport mechanism is indicated. It was observed that increasing substrate temperature, Ge contents, and dopant concentration lead to a decrease in the optical energy gap of those films. The role of the deposition conditions on values of the optical constants was determined. Accordingly, models of the density of states for the :H thin films as pure, doped with 3.5% of Al (p-type) and that doped with 3.5% As (n-type), were proposed.
Several attempts have been made to modify the quasi-Newton condition in order to obtain rapid convergence with complete properties (symmetric and positive definite) of the inverse of Hessian matrix (second derivative of the objective function). There are many unconstrained optimization methods that do not generate positive definiteness of the inverse of Hessian matrix. One of those methods is the symmetric rank 1( H-version) update (SR1 update), where this update satisfies the quasi-Newton condition and the symmetric property of inverse of Hessian matrix, but does not preserve the positive definite property of the inverse of Hessian matrix where the initial inverse of Hessian matrix is positive definiteness. The positive definite prope
... Show MoreThis study is qualitative, it illustrates H.G. Wells\\'s The Time Machine through the scientific and social framework of the Victorian Era. Wells\\'s portrayal of future societies examines the rapid technological progress and social changes of the 19th century. The analysis scrutinizes the division between the Eloi and the Morlocks, tracing the consequences of social division. To meet the objective of the study, Victorian frame of mind is utilized to examine the class struggle that is symbolized by the Eloi and the Morlocks. The analysis highlights the economic and social effects of industrialization and how Wells examines the capitalist system and its impact on human relationships and class division. The study also utilizes concepts from D
... Show MoreThis research aims to study the optical characteristics of semiconductor quantum dots (QDs) composed of CdTe and CdTe/CdSe core-shell structures. It utilizes the refluxed method to synthesize these nanoscale particles and aims to comprehend the growth process by monitoring their optical properties over varied periods of time and pH 12. Specifically, the optical evolution of these QDs is evaluated using photoluminescence (PL) and ultraviolet (UV) spectroscopy. For CdTe QDs, a consistent absorbance and peak intensity increase were observed across the spectrum over time. Conversely, CdTe/CdSe QDs displayed distinctive absorbance and peak intensity variations. These disparities might stem from irregularities in forming selenium (Se) layers a
... Show MoreZinc-indium-selenide ZnIn2Se4 (ZIS) ternary chalcopyrite thin film on glass with a 500 nm thickness was fabricated by using the thermal evaporation system with a pressure of approximately 2.5×10−5 mbar and a deposition rate of 12 Å/s. The effect of aluminum (Al) doping with 0.02 and 0.04 ratios on the structural and optical properties of film was examined. The utilization of X-ray diffraction (XRD) was employed to showcase the influence of aluminum doping on structural properties. XRD shows that thin ZIS-pure, Al-doped films at RT are polycrystalline with tetragonal structure and preferred (112) orientation. Where the
The size and the concentration of the gold nanoparticles (GNPs)
synthesized in double distilled deionized water (DDDW) have been
found to be affected by the laser energy and the number of pulses.
The absorption spectra of the nanoparticles DDDW, and the
surface plasmon resonance (SPR) peaks were measured, and found to
be located between (509 and 524)nm using the UV- Vis
spectrophotometer. SPR calculations, images of transmission
electron microscope, and dynamic light scattering (DLS) method
were used to determine the size of GNPs, which found to be ranged
between (3.5 and 27) nm. The concentrations of GNPs in colloidal
solutions found to be ranged between (37 and 142) ppm, and
measured by atomic absorptio
The effect of different Ti additions on the microstructure of Al-Ti alloy prepared by powder metallurgy was investigated. A certain amount of Ti (10wt%, 15wt%, and 20wt%) were added to aluminium and the tests like microhardness, density, scanning electron microscope (SEM), optical microscope (OM) and X-Ray Diffraction (XRD) were conducted to determine the influence of different Ti additives on the Al-Ti alloy properties and microstructure. The results show that the grains of α-Al changed from large grains to roughly spherical and then to small rounded grains with increasing Ti content, the micro-hardness of the alloy increases with increasing Ti, and XRD results confirm the formation of TiAl3 intermetallic co
... Show MoreBackground: In the present study used device jet plasma needle with atmospheric pressure which generates non thermal plasma jet to measure treatment potent with plasma against pathogenic bacteria founded in UTI was inactivated with plasma at 10 sec,
Objective:. This work included the application of the plasma produced from the system in the field of bacterial sterilization , where sample of Gram- negative bacteria (Escherichia coli) were exposed to intervals (1-10)second . Midstream Urine samples swabs were obtained from patients with urinary tract infections.
Type of the study: Cross -sectional study.
Methods: The work were used i
... Show MoreThe human stomach is home to the Gram-negative bacterium Helicobacter pylori, which has been connected to several gastrointestinal disorders. There may be a link between H. pylori infection and the start of autoimmune disorders, according to recent research. This review examines the intricate connections between persistent H. pylori infection, immune system dysregulation, and their possible role in initiating autoimmune disorders. The study begins with a summary of H. pylori infection and its prevalence worldwide, emphasizing the mounting data that connects this bacterium to autoimmune disorders. Then, using experimental data from animal models and epidemiological research as support, it undertakes a thorough review of autoimmune di
... Show MoreThe A.C conductivity of three samples of lanthanide oxide : zinc oxide (La2O3)1-x(ZnO)x pellets with different zinc oxide content which were sintered 1273 K temperatures were studied using LRC meters in the frequency range of 50–106 Hz at temperature of 30 °C. The a.c conductivity, was analyzed depending of the universal power law proposed by Jonsher,. The slope of the relation between logarithm of a.c conductivity and angular frequency represent the s value were in the range (0.44-0.77) which found to increase by increasing of zinc oxide content which coincided with the small po