This survey investigates the thermal evaporation of Ag2Se on glass substrates at various thermal annealing temperatures (300, 348, 398, and 448) °K. To ascertain the effect of annealing temperature on the structural, surface morphology, and optical properties of Ag2Se films, investigations and research were carried out. The crystal structure of the film was described by Xray diffraction and other methods.The physical structure and characteristics of the Ag2Se thin films were examined using X-ray and atomic force microscopy (AFM) based techniques. The Ag2Se films surface morphology was examined by AFM techniques; the investigation gave average diameter, surface roughness, and grain size mutation values with increasing annealing temperature (75.74 nm–96.36 nm). Additionally, With various variations to the nominal values, the absorbance and transmittance spectra are further studied and reported in accordance with the wavelength range of (400-1100) nm. The findings indicate that the sample highest absorbance value was attained at a temperature treatment of 448 K, whereas the sample highest transmittance was at a temperature treatment of 300 K. According to the results, direct transitions were permitted in the under-review thin films at optical energies of (2.15, 1.85, 1.75, and 1.7) eV, respectively
Background: Coated aesthetic archwires are currently the existing solutions for the esthetic problem, but the color of these archwires tends to change overtime. This study was aimed to evaluate the color stability of different types of esthetic archwires from four different companies at different time periods after immersion of two different staining drinks which are tea and Pepsi cola. Materials and methods: 48 specimens were prepared, each specimen contains 10 aesthetic archwires; and were divided according to type of solution into two groups: A (tea) &B (Pepsi cola); each group contained 24 specimens (12 specimens were immersed in the staining solution as 4 specimens for each time intervals and 12 specimens were immersed in distilled wa
... Show MoreThis study is concerned with a survey of seven species belonging to seven genera under two families and two orders found in some different areas of the Tigris River, especially since these areas have not been surveyed for a long time, and an attempt to identify the existing species at the present time after the recent water scarcity of the Tigris and Euphrates rivers and all water bodies interior of Iraq and the impact of this scarcity on the fish diversity found in some areas of the Tigris River in Baghdad.
In this work the corrosion behavior of Ti-6Al-4V alloy was studied by using galvanostatic measurements at room temperature in different media which includ sodium chloride (food salt), sodium tartrate (presence in jellies, margarine, and sausage casings,etc.), sodium oxalate (presence in fruits, vegetables,etc.), acetic acid (presence in vinegar), phosphoric acid (presence in drink), sodium carbonate (presence in 7up drink,etc.), and sodium hydroxide in order to compare.
Corrosion parameters were interpreted in th
... Show MoreGas hydrate formation poses a significant threat to the production, processing, and transportation of natural gas. Accurate predictions of gas hydrate equilibrium conditions are essential for designing the gas production systems at safe operating conditions and mitigating the problems caused by hydrates formation. A new hydrate correlation for predicting gas hydrate equilibrium conditions was obtained for different gas mixtures containing methane, nitrogen and carbon dioxide. The new correlation is proposed for a pressure range of 1.7-330 MPa, a temperature range of 273-320 K, and for gas mixtures with specific gravity range of 0.553 to 1. The nonlinear regression technique was applie
أن لعبة كرة السلة في تقدم وتطور مستمر حالها في ذلك حال الألعاب الرياضية الأخرى حيث أن الفضل في ذلك يعود إلى المعرفة بالعلوم المختلفة وكذلك البحث العلمي من اجل تحقيق نتائج متقدمة تنشدها معظم الدول ومنها العراق على الصعيد المحلي والعربي والدولي. ومما لاشك فيه أن متطلبات تطور مستوى نتائج القدرات البدنية في أيُة لعبة مرتبطة بالبرمجة والتخطيط الصحيح للمناهج التدريبية إذ تقودنا هذه الحقيقة إلى إجراء المزيد من الا
... Show MoreHard-grade asphalt binders like AC20-30 typically exhibit excessive stiffness, reduced penetration, and compromised workability, necessitating modification before use in paving applications. This study evaluates the efficacy of regular polyalphaolefin (PAO), a synthetic olefin-based lubricant, as a performance-enhancing modifying agent for such binders. AC20-30 was blended with PAO at dosages ranging from 2 wt.% to 10 wt.%, and the modified binders were characterized via penetration, ductility, softening point, and rotational viscosity measurements, alongside advanced rheological and chemical-morphological analyses. Incorporating PAO in AC20-30 asphalt progressively reduced the binder stiffness and enhanced its flexibility, with all modifie
... Show MoreDuring the last two decades, nanomaterial application has gained a significant attraction into asphalt technology due to their effect in enhancing asphalt binder improving the asphaltic mixture. This study will modify the asphalt binder with two different nano types, nano SiO2 and CaCO3, at levels ranging from 1% to 7%. The resulting optimum nano-modified Asphalt will be subject to a series of rheological tests, including dynamic shear rheometer (DSR), Viscosity, and bending beam rheometer (BBR) to determine asphalt binder sensitivity towards low-medium-high temperature range. Results indicate that both nano types improved the physical characteristics of Asphalt, and 5% by weight of Asphalt was suggested as a reasonable dosage of nano-SiO2
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