Optoelectronic devices, widely used in high energy and nuclear physics applications, suffer severe radiation damage that leads to degradations in its efficiency. In this paper, the influence of gamma radiation (137Ce source) and beta radiation (90Sr source) on the photoelectric parameters of the Si solar cell, based on the I–V characterization at different irradiation exposer, has been studied. The penetrating radiation produces defects in the base material, may be activated during its lifetime, becoming traps for electron–hole pairs produced optically and, this will, decrease the efficiency of the solar cell. The main objective of the paper is to study and measure changes in the I–V characteristics of solar cells, such as efficiency, maximum current, maximum power, and efficiency, due to the exposure of solar systems to different doses of γ and β irradiations
Additive aluminum powder to the polystyrene to prepare the composites Polystyrene– Aluminum.The samples were prepared by using mechanical compressed method at low pressure and a temperature 120°C. Measurements of absorbance and reflectance spectra were carried out by UV-Visible spectrophotometer , the effect of additive aluminum on the optical band gap Eop and optical constants ( refractive index n, extinction coefficient k ,dielectric constant ε and optical conductivity σop) were studied for the prepared composites . Results showed a decrease in the Eop with increasing perc
... Show MoreActivated carbon loading with metals oxides is new adsorbents and catalyst, which seem very promising for desulfurization process. The present study deals with the preparation of three metals oxides loaded on activated carbon (AC). The tri composite of ZnO/NiO/CoO/AC was characterized by X-Ray Diffraction (XRD), X-Ray florescence (XRF), N2 adsorption for BET surface area, pore volume and Atomic Force Microscopy (AFM). The effect of calcination temperature is investigated. The best calcination temperature is 250oC based on the presence of phase, low weight loss and keep at high surface area. The surface area and pore volume of prepared tri composite are 932.97m2/g and 0.6031cm3/g respec
... Show MoreIn this paper a new series of morpholine derivatives was prepared by reacting the morpholine with ethyl chloro acetate in the presence triethylamine as a catalyst in benzene gave morpholin-N-ethyl acetate(1) which reacted with hydrazine hydrate in ethanol, and gave morpholin-N-ethyl acetohydrazide (2) . Morpholin-N-aceto semithiocarbazide (3) were prepared by reacting compound(2) with ammonium thiocyanate , concentrated hydrochloric acid and ethanol as a solvent .Compound (3) reacted with sodium hydroxide and hydrochloric acid to give 5-(morpholin-N-methylene)-1H-1,2,4-triazole-3-thiol (4) .The new series of 1,2,4-triazol derivatives (5-8) was synthesized by reaction of compound(4) with formaldehyde , DMF as a solvent and different
... Show MoreIn this study, Schiff's bases [S3,S4] were synthezied by condensation of N,N-dimethyl amino benzaldehyde with primary aromatic amine[N-(hydrazinyl methyl)benzamide]. These Sciff's bases were found to react with maleic anhydride and phthalic anhydride to give 1,3Oxazepine[S5,S6,S7,S8] in good yields. The structures confired by m.p ,T.L.C.,FT.IR and 1H-NMR (of some of them).
A cermet (ceramic-metal) composite have been prepared from alumina (γ-Al2O3) reinforced with aluminum (Al) for the concentrations of (0, 10, 20, 30, 40, & 50) wt. %Al. The cermet was formed by single axial pressing, sintered in vacuum atmosphere. Compaction behaviors were studied in solid state sintering at sintering temperatures (400, 450, & 550) °C, sintering times (2, 4, & 6) hrs., and forming pressures (5, 10, 15) MPa, also in liquid phase sintering at (800 °C). The cermet was characterized by x-ray diffraction (XRD) and by scanning electron microscope (SEM), also physical and mechanical properties have been studied. SEM results showed the Al flowing inside the ceramic body due to uniform distribution of Al particles a
... Show MoreThis work contain many steps starting from esterification of isophthalic acid to yield diester compound [I] which was converted to their acid hydrazide [II], then the later compound reacted with ethylacetoacetate to yield pyrazol-5-one compound [III]. Afterword added acetyl chloride to give the compound [IV], the reaction of this compound with theiosemicarbazide led to produce a new carbothioamide compound [V], which was reacted with ethyl chloro acetate to yield the thioxoimidazolidin compound [VI]. The condensation reactions of this compound with different substituted aldehyde give new alkene derivatives [VII] ad. The synthesized compounds were characterized by melting points, FT-IR, 1H-NMR and Mass spectroscopy.
In this research, we prepared a polymer blend of polyvinylalcohol (PVA)/carrageenan/kaolinite by means of the solution cast approach. The composition of the blend was PVA in 1 gm by weight with 0.2 gm carrageenan as a plasticizer. The ratio of nanoclay varied between 1 and 5 wt%. Different properties were investigated in this study such as water vapor permeability, hardness, tear strength, color stability, thermal stability, and antibacterial activity. Water vapor permeability was decreased with increasing the ratio of nanoclay, while the values of hardness, tear strength, color stability, and thermal stability were increased. Also, the antibacterial activity examination with two types of bacteria, e.g.
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