Abstract: In the present work, the heat transfer of Nano Aluminum Oxide -NAO- has been studied practically to define the appropriate insulation conditions. This study focuses on finding of the amount of heat transfer through a glass substrate that is coated with nanoalumina doped on PMMA matrix. The optical and thermal properties were systematically investigated. The density of heat flow rate, was calculated in the range values (240-260) W/m2 while the optimum values confine between (250-260) W/m2 at temp. (25-35)Co. The results showed that the thermal insulation of the sample was significantly enhanced at temp. (30-50)Co. The simulated net heat transfer through window decreased linearly with increase of both of coating thickness concentration. Furthermore, the overall transmittance in the visible region and reflectance in infrared and ultraviolent regions decrease with increasing of weight content of the coated film.
The social networking sites have brought about fundamental changes and a qualitative shift in the marketing industry and its strategies. The Iraqi ministries have used this site i.e. Facebook to spread and disseminate values in order to consolidate it in Iraqi society which has witnessed many changes in all aspects of life.
The researcher studies the pages of both ministries to know the values contained in the publications of the pages of these two ministries, the quality of grooming as well as the forms in which these values are marketed.
The researcher uses a survey method and content analysis for the publications of these two pages during the study period starting from January 1, 2
... Show MoreThis paper presents a novel idea as it investigates the rescue effect of the prey with fluctuation effect for the first time to propose a modified predator-prey model that forms a non-autonomous model. However, the approximation method is utilized to convert the non-autonomous model to an autonomous one by simplifying the mathematical analysis and following the dynamical behaviors. Some theoretical properties of the proposed autonomous model like the boundedness, stability, and Kolmogorov conditions are studied. This paper's analytical results demonstrate that the dynamic behaviors are globally stable and that the rescue effect improves the likelihood of coexistence compared to when there is no rescue impact. Furthermore, numerical simul
... Show MoreThe effect of mixed corrosion inhibitors in cooling system was evaluated by using carbon steel specimens and weight loss analysis. The carbon steel specimens immersed in mixture of sodium phosphate (Na2 HPO4) used as corrosion inhibitor and sodium glocunate (C6 H11 NaO7) as a scale dispersant at different concentrations (20,40, 60, 80 ppm) and at different temperature (25,50,75 and 100)ºC for (1-5) days. The corrosion inhibitors efficiency was calculated by using uninhibited and inhibited water to give 98.1%. The result of these investigations indicate that the corrosion rate decreases with the increase the corrosion inhibitors concentration at 80 ppm and at 100ºC for 5 days, (i.e,
... Show MoreThe effect of using different R -molar ratio under variable reaction conditions (acidic as well as basic environment and reaction temperature) have been studied. The overall experiments are driven with open and closed systems. The study shows that there is an optimum value for a minimum gelling time at R equal 2. The gelling time for all studied open system found to be shorter than in closed system. In acidic environment and when R value increased from 2 to 10, the gelling time of closed systems has increased four times than open systems at T=30 ?C and fourteen times when temperature reaction increased to 60 ?C. While in basic environment the influence of increasing R value was limited.
Background: Sealers should demonstrate adhesive properties to dentin, decreasing the chance of endodontic treatment failure. Increased adhesive properties to dentin may lead to greater strength of the restored tooth, which may provide greater resistance to tooth fracture and clinical longevity of an endodontically treated tooth. The aim of this study was to evaluate the shear bond strength of Bioceramic iRoot SP sealer, AH plus sealer and Apexit plus sealer in absence or presence of smear layer using push out bond strength test. Materials and Methods: Sixty straight single roots of the mandibular premolars were selected for this study. All canals were instrumented using ProTaper rotary instruments to achieve tapered canal walls, instrumenta
... Show MoreThe objective of this work was to determine and compare the physiological changes in some: blood components (packed cell volume and hemoglobin) and plasma biochemical parameters (glucose, total protein, albumin, cholesterol and triglycerides) under 3 day of different types of stress: water deprivation, starvation, overcrowding and handling stress. Twenty five male Wister rats weighted 100-120 gm, were divided randomly into five groups: control, water deprivation, starvation, overcrowding and handling stress. On the third day of stress the animals anesthetized for blood collection; the results of blood component revealed a significant increase in PCV and a significant decrease in Hb of water deprivation group and starva
... Show MoreThis work deals with the production of light fuel cuts of (gasoline, kerosene and gas oil) by catalytic cracking treatment of secondary product mater (heavy vacuum gas oil) which was produced from the vacuum distillation unit in any petroleum refinery. The objective of this research was to study the effect of the catalyst -to- oil ratio parameter on catalytic cracking process of heavy vacuum gas oil feed at constant temperature (450 °C). The first step of this treatment was, catalytic cracking of this material by constructed batch reactor occupied with auxiliary control devices, at selective range of the catalyst –to- oil ratio parameter ( 2, 2.5, 3 and 3.5) respectively. The conversion of heavy vacuum gas
... Show MoreCorrosion behavior of aluminum alloy 7025 was investigated in hydrochloric acid (pH=1) containing 0.6 mol.dm-3 NaCl in the existence and absence of diverse concentrations of sulphamethoxazole as environmentally friendly corrosion inhibitor over the temperature range (298-313)K. Electrochemical polarization method using potentiostatic technique was employed. The inhibition efficiency has been raised with increased sulphamethoxazole concentration but lessened at temperature increases. The highest efficiency value was 96.5 at 298 K and 2 x10-4 mol.dm-3 concentration of sulphamethoxazole. The sulphamethoxazole adsorption was agreed with Langmuir adsorption isotherm. Some thermodynamic parameter (△Gads) and activation energy (Ea) were determin
... Show MoreThe present study was conducted to evaluate the effect of different inhibitors on the corrosion rate of aluminum in 50% (v/v) ethylene glycol solution at 80°C and pH 8.0 in which the electrochemical technique of linear sweep voltammetry was employed to characterize each inhibitor function and to calculate the corrosion rate from Tafel plots generated by a computer assisted potentiostat.
It is found that both sodium dichromate and borax reduces the corrosion rate by polarizing the anodic polarization curve while sodium phosphate, potassium phosphate, and sodium benzoate reduces the corrosion rate by polarizing both the anodic and cathodic polarization curve.
When inhibitor concentration increases from I g/l up
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