In this research an experimental study has done for testing the thermal performance of selective surfaces used in solar collectors for substrate of iron, galvanized iron and aluminum which are commercially available. The coating process for the samples has done in two ways, the electroplating and the chemical spray pyrolysis. The results of the thermal performance test of these samples are comparing with the thermal performance of a sample without paint and other paint with black paint without shines commercially available. For the electroplated samples, the performance study has done for different immersion time in plating bath, the
distance between electrical poles, the current density, and area ratio of the sample plated area to the nickel pole face area. The chemical sprayed pyrolysis samples, study has done for different coating times, atomizing gas pressures, distance between the aperture of atomizer and the sample and the paint mass flow rate. The results showed that the best performance of the iron's
samples is the sample which is coated with two layers. The first layer is of zinc done by electroplating where the time of plating is (2 min.) and the second layer is of black nickel done by electroplating, where the time is (20 min.), the distance between the poles is (6 cm), the current density is (0.15 A/dm2 ) and area ratio of the sample plated area to the nickel pole face area is equal to (1). The percentage of the increasing in heat storage of electroplating sample to galvanized iron sample without paint at the beginning of testing the performance of samples and at the end were (58.23%& 44.97%) respectively. For aluminum samples, the best performance was regarded for two samples electroplating sample and chemical spray pyrolysis sample. The best electroplating sample was coated with a layer of black nickel where the time of plating is (20 min.), the distance between the poles is (6 cm), the current density is (0.15 A/dm2) and area ratio of the sample plated area to the nickel pole face area is equal to (1). While the best chemical spray pyrolysis sample has been coated with a layer of black nickel where the time of plating is (16 sec.) and the distance between the aperture of the reservoir and the surface of the sample is (27 cm), the amount of flow is (4.8 ml / min.), the atomizing gas pressure is (1 bar) and temperature of the sample surface is (290 0C).
The measurements of major and trace elements in different brands of milk powder selected from the Iraqis market via the X-ray fluorescence (XRF) Technique have been studied in the present work. The result of the measurements reveals the high concentrations of sodium, phosphorus, sulfur, chlorine, potassium, calcium and magnesium. Furthermore, low concentrations of aluminum, silicon, iron, bromine, molybdenum, iodine, barium, titanium, manganese, cobalt, chrome, nickel, copper, zinc and lead were detected. Neutron activation analysis (NAA) and Kjeldahl technique were also employed to determine the concentrations of nitrogen. It was found that the nitrogen concentration was in the range of (1.96 - 3.23) % which is within the permissible li
... Show MoreThe current study was conducted to determine the sensitivity of some pathogenic bacterial isolates isolated from wounds and burns water toward the disposer of the Yas Rue tested five crude bacterial isolates isolated from wounds and burns which these isolates sensitive to aqueous extract crude
EM International
Background: The final stage of endodontic therapy is complete obturation of the root canal system to provide as perfect as possible at the cementodentinal junction of the apical foramen. The purpose of this in vitro study was to evaluate the sealing ability of injection molded thermoplasticized gutta percha and lateral condensation techniques with and without the use of sealers. Materials and Methods: Forty freshly extracted adult human maxillary central incisors with complete formed apices were utilized in this study. The teeth were randomly divided into four groups for evaluation of the apical seal. Group (1) lateral condensation gutta percha technique without sealer, (2) lateral condensation gutta percha technique with sealer, (3) Inject
... Show MoreThe purpose of this paper is to gain a good understanding about wake region behind the car body due to the aerodynamic effect when the air flows over the road vehicle during its movement. The main goal of this study is to discuss the effect of the geometry on the wake region and the aerodynamic drag coefficient. Results will be achieved by using two different shapes, which are the fastback and the notchback. The study will be implemented by the Computational Fluid Dynamic (CFD) by using STAR-CCM+® software for the simulation. This study investigates the steady turbulent flow using k-epsilon turbulence model. The results obtained from the simulation show that the region of the air separation behind the vehicle
... Show MoreThe current study suggested a thermal treatment as a necessary proactive step in improving the adsorption capacity of bio-waste for contaminants removal in wastewater. This approach was based on the experimental and histological investigation of biowaste pods shell. This investigation showed that these shells compose of parenchyma cells that store secondary metabolites compounds produced from cells were exhibited in present study. The results also reported that these compounds are extracted directly from the cells as soon as they are exposed to an aqueous solution, hampering their use as an adsorbent material. The increase in the weight of bio-waste adsorbent at unit liquid volume increases the production of secondary metabolites compounds
... Show MoreThe electronic properties (such as energy gap HOMO levels. LUMO levels, density of state and density of bonds in addition to spectroscopic properties like IR spectra, Raman spectra, force constant and reduced masses as a function of frequency) of coronene C24 and reduced graphene oxide C24OX , where x=1-5, were studied.. The methodology employed was Density Functional Theory (DFT) with Hybrid function B3LYP and 6-311G** basis sets. The energy gap was calculated for C24 to be 3.5 eV and for C24Ox was from 0.89 to 1.6862 eV for x=1-5 ,respectively. These energy gaps values are comparable to the measured gap of Graphene (1-2.2 eV). The spectroscopic properties were compared with experimental measurements, specificall
... Show MoreThis study was carried out at Poultry Research Station, State Board of Agricultural Research, Ministry of Agriculture for the period from 27 September 2014 to 9 November 2014 to evaluate the Supplementation of different levels of Conjugated Linoleic Acid (CLA) on productive performance of broiler. Four hundred eighty chicks (Ross-308),one day old were randomly distributed to four dietary treatments for 42 days of age with 3 replicates/vtreatment (40 bird/replicate). Experimental treatments were as follow; T1 (Control diet) without supplement, while the treatment T2,T3 and T4 were Supplemented with 1, 1.5, 2 g CLA /kg diet respectively. The results showed significant (P ≤ 0.05) increased in mean of body weight, weight gain, ave
... Show MoreLactobacillus Plantarum and Lactobacillus rhamnosus GG were encapsulated using 3% of alginate via extrusion technique. And the probiotics capsules produced were further coated used 1% chitosan to increase the survival of probiotics, and evaluation of The heat resistance of the slow pasteurization and fast pasteurization for Lb,pla and Lb.GG for control and bacteria coated one layer and bacteria coated two layer at 63°C/ 30 minutes and 72°C/ 15 seconds. The results indicate that the Probiotic coated two layer are more resistant to pasteurization temperatures at 63°C/ 30 minutes and 72°C/ 15 seconds than the Probiotic coated one layer. While the results of the control follow a significant reduction for viability of cell toward pasteuri
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