This paper aims to study the effect of circular Y-shaped fin arrangement to improve the low thermal response rates of a double-tube heat exchanger containing Paraffin phase change material (PCM). ANSYS software is employed to perform the computational fluid dynamic (CFD) simulations of the heat exchanger, including fluid flow, heat transfer, and the phase change process. The optimum state of the fin configuration is derived through sensitivity analysis by evaluating the geometrical parameters of the Y-shaped fin. For the same height of the fins (10 mm), the solidification time is reduced by almost 22%, and the discharging rate is enhanced by almost 26% using Y-shaped fins compared with the straight fins. The results demonstrate that the solidification time is inversely proportional to the fin's length. The heat release rate for the case with the longest fins (stem length of 10 mm) is 39 W, almost 2.8 times higher than that with the fins' stem length of 5 mm. The case with the tributary's angle of 22.5o solidified in 55 min, faster than the other studied angles. Increasing the number of fins significantly affects the solidification time and discharging rate. By increasing the number of fins from 3 to 9, the heat transfer rate improves by 194%. The advantages of circular Y-shaped fins are well known in heat transfer applications and therefore are characterized toward higher performance in this study for the first time during the solidification process.
The spectral propetties (absorption and fluorescence) of Coumarine-47 laser dye have been studied. This type of laser dye belong the Coumarine family and it has dissolved in chloroform at different concentrations (1x10-5, 5x10-5, and 1x10-4 M) at room temperature. The achieved results have been pointed out to increase in the absorption and fluorescence as the concentration increased which are agreements with Beer – Lambert law. These have been also showed an expansion in the spectral range of absorption and fluorescence with a noticed shift in the direction of longer wavelength (Red-shift) with increasing concentration. The quantum efficiency of the dissolved C47 in chloroform has been computed by using the brevious concentrations
... Show MoreA total of 72 specimens of the wild jungle cat Felis chaus furax De Winton, 1898 were
examined for the purpose of this study. The results show that 55.6% of the sample harbored
either single or mixed infections with ecto- and/ or endoparasites. The mode of infection
shows that only four specimens( 5.6% of the total sample) acquire single infections, the
double infections comprise 15.3%, the triple infections comprised 33.3%, while the
quadruplicate infections comprised 1.4%.
The systematic list of the parasites included six ectoparasites: Ctenocephalides felis (insect),
Sarcoptes scabiei (mite), Haemaphysalis adleri, Rhipicephalus leporis, Rhipicephalus
turanicus and Hyalomma anatolicum excavatum (ticks) and seven
Basketball is one of the most popular and popular games that have a large audience both globally and locally because of the magic it contains in terms of performance. For this sport to be a success, fundamental factors must exist and these factors is the referee. The referee plays a large and important role in the success of the game and the establishment and application of rules.The research aimed at identifying the effect of special on the development of referee's physical abilities. The researcher used the experimental method. The subjects were (12) first class basketball referees. The researcher recommended using special exercises due to their great role in developing the physical abilities of first class basketball referees
Objective(s): To assess the practices of early childhood’s mothers regarding toilet training and to find out the relationship between mothers’ practices and their socio-demographic characteristics and their children’s demographic characteristics.
Methodology: A descriptive study is conducted at primary health care centers in Al-Rusafa District in Baghdad City for the period of September 19th 2020 to March 16th 2021. Non probability “convenient” sample of (225) early childhood’s mothers is selected. A questionnaire format is designed and composed of two parts: the first part includes mothers’ socio-demographic characteristics and their children and the second part includes structured close-ended questions to assess the p
Natural Bauxite (BXT) mineral clay was modified with a cationic surfactant (hexadecy ltrimethy lammonium bromide (BXT-HDTMA)) and characterized with different techniques: FTIR spectroscopy, X-ray powder diffraction (XRD) and scanning electron microscopy (SEM). The modified and natural bauxite (BXT) were used as adsorbents for the adsorption of 4- Chlorophenol (4-CP) from aqueous solutions. The adsorption study was carried out at different conditions and parameters: contact time, pH value, adsorbent dosage and ionic strength. The adsorption kinetic (described by a pseudo-first order and a pseudo-second order), equilibrium experimental data (analyzed by Langmuir, Freundlich and Temkin isotherm models) and thermodynamic parameters (change in s
... Show MoreIn order to investigate the presence of methicillin or multidrug resistant Staphylococcus aureus in food-chain especially Cows raw milk and white raw soft cheese and its whey, a total of 30 samples were collected randomly from different markets in Baghdad Province during December 2012 till February 2013, in which samples were analyzed by a standard isolation protocols of food microbiology with some modification processing by new, modern and rapid technology tools such as chromogenic medium Baird-Parker agar, Electronic RapIDTM Staph Plus Code Compendium Panel System (ERIC®) Dryspot Staphytect Plus and Penicillin Binding Protein (PBP2') Plus assays; as well as, studying the susceptibility of isolates to different selected antibiotics. The r
... Show MoreThe selection of proper field survey parameters of electrical resistivity can significantly provide efficient results within a reasonable time and cost. Four electrode arrays of 2D Electric Resistivity Imaging (ERI) surveys were applied to characterize and detect subsurface archaeological bodies and to determine the appropriate array type that should be applied in the field survey. This research is to identify the subsurface features of the Borsippa archaeological site, Babylon Governorate, Middle Iraq. Synthetic modeling studies were conducted to determine the proper array and parameters for imaging the shallow subsurface features or targets. The efficiency of many array types has been tested for the detection the buried archaeolog
... Show MoreThat internal control is particularly important in improvingperformance and tax reform، they play an important role in the regularity ofwork and development and the anti corruption and activating the decisionsand tax legislation، as contained in the organizational plan and the means،procedures and components designed from which to ensure a policy andimplementation plans The research aims to review the reality of the internalcontrol in the General Commission for Taxes and stand on the deficiencies init, with the strengthening of the role of internal control in the GeneralAuthority for taxes based on the laws and regulations and by using modernmeans to work as well as developing the performance of employees in thebody، including helpin
... Show MoreBackgrround:: Cholera is gastroenteritis caused by enterotoxin producing Vibrio cholera. Cholera is predominantly a waterborne disease especially in countries with inadequate sanitation. Several rapid methods have been developed and used to detect V. cholerae serotypes directly from stools.
Objjecttiives:: to evaluate a rapid and accurate method for the diagnosis of cholera caused by V. cholerae O1 and O139 serogroups d to find the incidence of sporadic cases of cholera in Baghdad.
Metthods:: Sixty four stool samples were collected from four hospitals in Baghdad. The age of patients ranging from two months to 12 years, 26 were females and 38 males. Immunochromatographic visual test for qualitative detection of O1 and /or O139 serog