In this work, (Cu1-xAgx)2ZnSnSe4 (CAZTSe) alloys with various silver content (x= 0.0, 0.1and 0.2) have been prepared by reacting their high purity elements (Cu, Ag, Zn, Sn and Se) in an evacuated quartz tube under pressure of 10 -3Torr. The composition of the prepared alloys was determined by energy dispersive X-ray spectroscopy (EDXS) analysis, the results were close to the theoretical values. CAZTSe thin films with a thickness of 800 nm were deposited by thermal evaporation technique on glass substrates at room temperature (RT) with a deposition rate of 0.53nm/sec. Similarly, CdS thin films were deposited with a thickness of 100 nm on the same substrates at RT with a deposition rate of 0.3nm/sec from ready-made CdS alloy powder. All prepared thin films were annealed at temperatures of 373K and 473K under vacuum (10-3Torr) for 1h. X-ray analysis showed that all CAZTSe alloys and their thin films were polycrystalline and have the tetragonal structure with preferential orientation in the (112) direction, while all thin CdS films were polycrystalline and have the hexagonal structure with preferential orientation in the (002) direction. The scanning electron microscopy (SEM) technique was used to study the surface morphology of all prepared CAZTSe films, while the atomic force microscopy (AFM) technique was used to study the surface topography of all prepared CAZTSe and CdS films. SEM results revealed that CAZTSe films had uniform surface features with irregular sized grains, while AFM results showed that the surface roughness and the average grain size of CAZTSe and CdS thin films increased with increasing Ag content for CAZTSe thin films and annealing temperature for CAZTSe and CdS thin films. The absorbance and transmittance spectra for CAZTSe and CdS thin films were recorded in the wavelength ranges of (400-1100) nm and (350- 1100) nm, respectively. Optical measurements showed that all CAZTSe and CdS thin films have a direct energy gap (Eg) that decreased with increasing silver content for CAZTSe thin films and annealing temperature (Ta) for both types of prepared thin films, so it decreased from 1.73 eV to1.5 eV when x content increased from 0.0 to 0.2 and decreased from 1.5 eV to1.46 eV and from 2.47 eV to 2.38 eV when Ta increased from RT to 473K for CAZTSe thin films with x content equal to 0.2 and CdS thin films, respectively. Optical constants such as extinction coefficient, refractive index and dielectric constant were calculated for all prepared thin films. The measurements of the electrical properties for prepared films showed that the D.C electrical conductivity (σd.c) increased with increasing Ag content for CAZTSe thin films and annealing temperature for both types of thin films. So the electrical conductivity changed from 1.1276*10-2 (Ω.cm)-1 to 28.9266*10-2 (Ω.cm)-1 when x changed from 0.0 to 0.2 and changed from 28.9266*10-2 (Ω.cm)-1 to 57.4599*10-2 (Ω.cm)-1 and from 4.0476*10-4 (Ω.cm)-1 to 9.4227*10-4 (Ω.cm)-1 when Ta changed from RT to 473K for CAZTSe thin films with Ag content equal to 0.2 and CdS thin films, respectively. The prepared thin films have two activation energies (Ea1 & Ea2) in the temperature ranges of (318-488)K and (313-443)K for CAZTSe and CdS films, respectively. The results of Hall effect for CAZTSe thin films showed that all films were of acceptor type and the concentration of holes in them decreased with increasing silver content and annealing temperature, while CdS thin films were of donor type and the concentration of electrons in them increased with increasing annealing temperature. In this research, solar cells were fabricated from CdS/CAZTSe/Si structurThe C-V measurements revealed that all prepared heterojunctions were of the abrupt type and the junction capacitance and carrier concentration reduced while the width of depletion region and the built-in potential increased with increasing the silver content and annealing temperature. The current-voltage characteristics under dark condition of CAZTSe heterojunctions showed that both the ideality factor and saturation current decreased with increasing Ag content and annealing temperature. While,The current-voltage characteristics under dark condition of CAZTSe heterojunctions showed that both the ideality factor and saturation current decreased with increasing Ag content and annealing temperature. While, the current-voltage measurements under illumination showed that the performance of heterojunction solar cell improved with increasing Ag content and annealing temperature. The result indicated that the prepared solar cell with 0.2 Ag content and 473K annealing temperature exhibited the highest efficiency (η = 2.827%) compared to other prepared solar cells
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In this article four samples of HgBa2Ca2Cu2.4Ag0.6O8+δ were prepared and irradiated with different doses of gamma radiation 6, 8 and 10 Mrad. The effects of gamma irradiation on structure of HgBa2Ca2Cu2.4Ag0.6O8+δ samples were characterized using X-ray diffraction. It was concluded that there effect on structure by gamma irradiation. Scherrer, crystallization, and Williamson equations were applied based on the X-ray diffraction diagram and for all gamma doses, to calculate crystal size, strain, and degree of crystallinity. I
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The target of this study was to synthesize several new Ciprofloxacin drug analogs by providing a nucleophilic substitution procedure that provides new functionality at the carboxylic group location. The analogs were synthesized, designed, and characterized by 1HNMR, and FTIR. The synthetic path began from the reaction of ciprofloxacin drug with morpholine to give compound[B], ciprofloxacin derivative was linked with a variety of primary and secondary amines to give compounds[B1-B9]. The above-mentioned prepared compounds [B3 and B5] were applied to liver enzymes, and the increase in the activity of these enzymes was observed. In addition, a theoretical study was conducted to study the energies and properties of the prepared co
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The target of this study was to synthesize several new Ciprofloxacin drug analogs by providing a nucleophilic substitution procedure that provides new functionality at the carboxylic group location. The analogs were synthesized, designed, and characterized by 1HNMR, and FTIR. The synthetic path began from the reaction of ciprofloxacin drug with morpholine to give compound[B], ciprofloxacin derivative was linked with a variety of primary and secondary amines to give compounds[B1-B9]. The above-mentioned prepared compounds [B3 and B5] were applied to liver enzymes, and the increase in the activity of these enzymes was observed. In addition, a theoretical study was conducted to study the energies and properties of the prepared compounds.
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In this work we present a detailed study on anisotype nGe-pSi heterojunction (HJ) used as photodetector in the wavelength range (500-1100 nm). I-V characteristics in the dark and under illumination, C-V characteristics, minority carriers lifetime (MCLT), spectral responsivity, field of view, and linearity were investigated at 300K. The results showed that the detector has maximum spectral responsivity at λ=950 nm. The photo-induced open circuit voltage decay results revealed that the MCLT of HJ was around 14.4 μs
The performance of single and two stage solar concentrator were studied ' " The ratio of the primary to the secondary mirrors diameter is taking to be 0.5, depending on the theoretical calculation for the accumulated energy by the concentrator with ratio between 0.0 to 0.9. The design of the systems were designed and examined by using a ray-tracing program. The efficiency of the single and the two stage concentrators are calculated and compared with and without cooling systems.
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