The structural, optical and electrical properties of ZnS films prepared by vacuum evaporation technique on glass substrate at room temperature and treated at different annealing temperatures (323, 373, 423)K of thickness (0.5)µm have been studied. The structure of these films is determined by X-ray diffraction (XRD). The X-ray diffraction studies show that the structure is polycrystalline with cubic structure, and there are strong peaks at the direction (111). The optical properties investigated which include the absorbance and transmittance spectra, energy band gab, absorption coefficient, and other optical constants. The results showed that films have direct optical transition. The optical band gab was found to be in the range to (2.96-3.06)eV with increasing annealing temperatures. The electrical properties of these films have been studied, it was observed that D.C conductivity at room temperature decreases with the increase of annealing temperatures, and the mechanism of conductivity occurs in two ranges of temperature, from Hall measurements the conductivity for all samples of ZnS films is n-type.
يعد علم التدريب الرياضي الحديث عملية تربوية علمية مبنية على اسس صحيحة هدفها وصول اللاعبين الى التكامل في الاداء الفني وهذا يتم عن طريق التأثير المنظم والدقيق بواسطة استعمال التمارين البدنية التي تحدث تغيرات خاصة في عمل اعضاء واجهزة جسم الرياضي والتي بدورها تؤدي الى رفع كفاءة الاعضاء والاجهزة لتحقيق الانجازات الرياضية العالية ولقد استعملت الباحثتان اسلوب حديث من اساليب التدريب الرياضي من اجل تطوير تحم
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Polymers, being one of the most important materials in dentistry, offer great physical and mechanical qualities, as well as good biocompatibility. Aim of this study was done to evaluate the Polyetherketoneketone and Polyetherketoneketone polymer composite material used as dental implant through tensile strength, Fourier Transform Infrared analysis FTIR, and wettability). Polyetherketoneketone composites (Polyetherketoneketone and Strontium-containing hydroxyapatite) with selected weight percentage ratios of (0, 10%, 20%, 30%), were fabricated using a compression molding technique”, The study involved Samples preparation (sheets) shaped and form into the desired shape according to standard for tests which included tensile strength,
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This article includes designed and synthesized for bent-shaped liquid crystal molecules starting from 5,5-diethylpyrimidine-2,4,6(1H,3H,5H)-trione and two moles of chloroacetylchloride in N, N-dimethyl formamide (DMF) and triethylamine (TEA) to product compound [I] ,then reacted the later compound with two moles of 4-hydroxybenzonitrile to yield nitrile compound [II]. Likewise, reaction 5,5-diethylpyrimidine-2,4,6(1H,3H,5H)-trione and two moles of ethylchloroacetate with fused sodium acetate in ethanol to create an ester compound [III], and then the later compound was reacted with two moles of hydrazine hydrate in ethanol to obtained hydrazide acid compound [IV]. After that, the compound [IV] reacted with two moles of ethyl acetoacetate in
... Show MoreDensity Functional Theory (DFT) with B3LYP hybrid exchange-correlation functional and 3-21G basis set and semi-empirical methods (PM3) were used to calculate the energies (total energy, binding energy (Eb), molecular orbital energy (EHOMO-ELUMO), heat of formation (?Hf)) and vibrational spectra for some Tellurium (IV) compounds containing cycloctadienyl group which can use as ligands with some transition metals or essential metals of periodic table at optimized geometrical structures.
The job that confronts players with the effectiveness of shooting with an air rifle is high, so it requires necessary functional adaptations that differ in their degrees from other sports. Regular training in air rifle shooting leads to physiological changes in most of the body's internal systems, and changes and responses can be identified. The functional accompanying physical activity through the presence of body components that reflect these physiological changes in the form of changes in some components, and the importance of research lies in studying the physiological changes accompanying the maximum physical effort and the consequent development of the level of achievement in the effectiveness of shooting with air rifle and body
... Show MoreBackground: Orthodontic tooth movement is characterized by tissue reactions, which consist of an inflammatoryresponse in periodontal ligament and followed by bone remodeling in the periodontium depending on the forces applied. These processes trigger the secretion of various proteins and enzymes into the saliva.The purpose of thi study was to evaluate the activity of alkaline phosphatase (ALP) in saliva during orthodontic tooth movement using different magnitude of continuous orthodontic forces.
Materials and Methods: Thirty orthodontic patients (12 males and 18 females) aged 17-23 years with class II division I malocclusion all requiring bilateral maxillary first premolar extractions were randomly divided into three groups according t
The research aim to measure the impact of the Industry specialization of the auditors on the quality in audit in Iraqi auditing firms, as well as measuring the factors of Industry specialization in the Iraqi audit companies by measuring the market shares of Iraqi audit firms that audit the companies listed on the Iraqi Stock Exchange For 2010 to 2016, by surveying the opinions of (35) Audit firm on the impact of the Industry specialization of auditing firms in audit quality factors, The effect of the variables was revealed through the use of the survey form Distributed to Iraqi audit companies, The industry speci
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