In this study, pebble bed as an absorber and storage material was placed in a south facing, flat plate air-type solar collector at fixed tilt angle of (45°). The effect of this material and differ- ent parameters on collector efficiency has been investigated experimentally and
theoretically. Two operation modes were employed to study the performance of the solar air heater. An inte- grated mode of continuous operation of the system during the period of (11:00 am – 3:00 pm) and non-integrated mode in which the system stored the solar energy through the day then used the stored energy during the period of (3:00 pm – 8:00 pm). The results of parametric study in case of continuous operating showed that the maximum average temperature difference of air between inlet and outlet sections observed on (0.018 kg/s) air mass flow rate were exceeded (17°C) and the maximum outlet temperature that got was exceeded (34°C) for the three months (December, January and February) of experiments. Average efficiency was ranged from 53% to 65%. In the case of storage and then operating, the maximum outlet air temperature was ranged from (27°C) up to (31°C) then
decreased with spend of energy to reach (13°C) to (18°C) and the maximum storage energy was (165.14 W) for the porosity of (0.29) , height of (20 cm) and (0.01 kg/s) mass flow rate. The results also, showed that the solar air collector supplied a solar heating fraction (SHF) with an average of (0.65) for a meeting room (3 * 4 * 7 m) located in Baghdad as a case study.
Abstract
The study of oxygen mass transfer was conducted in a laboratory scale 5 liter stirred bioreactor equipped with one Rushton turbine impeller. The effects of superficial gas velocity, impeller speed, power input and liquid viscosity on the oxygen mass transfer were considered. Air/ water and air/CMC systems were used as a liquid media for this study. The concentration of CMC was ranging from 0.5 to 3 w/v. The experimental results show that volumetric oxygen mass transfer coefficient increases with the increase in the superficial gas velocity and impeller speed and decreases with increasing liquid viscosity. The experimental results of kla were correlated with a mathematical correlation des
... Show MoreSurgical site infections are the second most common type of adverse events occurring in hospitalized patients. Surgical antibiotic prophylaxis refers to the use of preoperative and postoperative antibiotics to decrease the incidence of postoperative wound infections. The objective of this study was to evaluate the antibiotic administration pattern for surgical antibiotic prophylaxis and the adherence to American Society of Health-System Pharmacists surgical antibiotic prophylaxis guideline in Medical City Teaching Hospitals/Baghdad. The medical records of one hundred patients who underwent elective surgical procedures were reviewed. Adherence to the recommendations of American society of health‑system pharmacists guideline was ass
... Show MoreT-joints are common structures encountered in the assemblage of many industrial applications due to their advantages. However, joining these structures when using Friction Stir Welding (FSW) could be prone to defects that cause severe consequences like loss of strength and fracture. The current paper implements an experimental procedure to assess the effect of geometrical tool shape on void formation in friction stir welded AA 6061-T6 T-joint configuration. Taguchi optimization method was put into service to minimize the number of experiments and fulfil the goal of discovering the optimal FSW parameters that allow the manufacturing of such configurations with high mechanical properties. X-ray radiography and micrograph images were u
... Show MoreThe main idea of this research is to consider fibrewise pairwise versions of the more important separation axioms of ordinary bitopology named fibrewise pairwise - spaces, fibrewise pairwise - spaces, fibrewise pairwise - spaces, fibrewise pairwise -Hausdorff spaces, fibrewise pairwise functionally -Hausdorff spaces, fibrewise pairwise -regular spaces, fibrewise pairwise completely -regular spaces, fibrewise pairwise -normal spaces and fibrewise pairwise functionally -normal spaces. In addition we offer some results concerning it.
Inflation is one of the important issues that the economic authorities in all countries of the world care about, where the loss of money for its function is one of the most important and largest inflationary effects that this phenomenon leaves on the economy, and Iraq, like other countries, has had its share of the problem of inflation for a long time due to the circumstances that He went through it, whether it was the wars he fought or the economic blockade that was imposed on him in the nineties of the last century. Economically, the problem of inflation is addressed through the use of fiscal policy tools, including tax increases in order to abso
... Show MoreThis thesis aims to show the effects of the development of the traditional manual system of the tax accounting process to the electronic system by the activation of the tax identification numbers (TINs) mechanism. The impact of this development is facilitating the tax accounting process, tax fraudand thus increasing the tax outcome.To prove the research hypothesis, an electronic system was designed based on income tax report, estimation note of individuals, in additional to using Adobe Dreamweaver application to write PHP, HTML, Javascript, and CSS web languages to implement the proposed system. The research reached a set of conclusions, the most important of which is; not enough the communication methods between the Genera
... Show MoreBackground: Antioxidant, sedative, anticancer, and antibacterial properties are among the numerous pharmacological characteristics of Galium verum. Aim: The primary goal of this research was to investigate the therapeutic effects of G. verum extract against folic acid-induced acute kidney injury (AKI). Materials and methods: 18 male rats were assigned into three groups: Control, AKI, and G. verum. AKI was induced by a dose of folic acid (250 mg/kg, i.p.) while G. verum (250 mg/kg) was administrated for 7 consecutive days. Results: G. verum methanol extract contains flavonoids, anthraquinones, tannins, iridoids, triterpen
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