This paper presents an experimental and theoretical analysis to investigate the two-phase flow boiling heat transfer coefficient and pressure drop of the refrigerant R-134a in the evaporator test section of the refrigeration system under different operating conditions. The test conditions considered are, for heat flux (13.7-36.6) kW/m², mass flux (52-105) kg/m².s, vapor quality (0.2-1) and saturation temperature (-15 to -3.7) ˚C. Experiments were carried out using a test rig for a 310W capacity refrigeration system, which is designed and constructed in the current work. Investigating of the experimental results has revealed that, the enhancement in local heat trans

An experimental study was conducted on pressure drop of water flow through vertical cylindrical packed beds in turbulent region and the influence of the operating parameters on its behavior. The bed packing was made of spherical and non-spherical particles (spheres, Rasching rings and intalox saddle) with aspect ratio range 3.46  D/dp  8.486 obtaining bed porosities 0.396 0.84 and Reynolds number 1217  21758. The system is consisted of 5 cm inside diameter Perspex column, 50 cm long; distilled water was pumped through the bed with flow rate 875, 1000, 1125, 1250,1375 and 1500 l/h and inlet water temperature 20, 30, 40 and 50 ˚C. The packed bed system was monitored by using LabVIEW program, were the result

Presupposition is the background belief that is known by both the speaker and the addressee, it is tied to particular words and aspects of the surface structure that act as linguistic triggers. The present study aims at investigating whether Iraqi fourth -year university students are able to recognize the English presuppositions through the meaning of these linguistic triggers .To fulfil the basic requirements of the study, the researcher has conducted a test . The results of the study have validated the hypothesis of the work and it is found that the linguistic triggers are important tools in recognizing presuppositions.    

Gas sensors based on titanium dioxide (TiO₂) and zinc oxide (ZnO) nanocomposites are considered energy-saving devices that are utilized to find dangerous or harmful gases in an environment. The performance of nitrogen dioxide (NO₂) gas sensors have been improved by spin-coating a TiO₂ and TiO₂:ZnO nanocomposite with varying concentrations (₉₀TiO₂:₁₀ZnO, ₇₀TiO₂:₃₀ZnO, and ₅₀TiO₂:₅₀ZnO). To correlate structural properties with gas-sensing behavior, structural and morphological characterization has been done using FESEM, XRD, and EDX.  Without any ZnO-specific crystalline phase, TiO₂

This study aims to document and describe the speech sounds and sound inventory that are present in Sorani which is dialect of Kurdish and compare the results with their English counterparts.  The research concentrates on the voicing system and the quality of Sorani sounds which are measured by using the voice onset time (VOT) of the stop consonants, and the first three formants of the vowel sounds; the closure duration of voiceless stop consonants in medial position is measured as well.

Ten native speakers of the Sorani dialect (5 males and 5 females) participated in this experiment. All speakers are between 20 and 50 years of age, were born in Sulaimanyiah, migrated to the US, and remain in the US at the time of recording.

The main problem of the current study concentrates on applying critical discourse analysis to examine textual, discoursal and social features of reduplication in some selected English newspaper headlines. The main aim of the current study is to analyze the linguistic features of reduplication by adopting Fairclough's three-dimensional model (2001). This study sets forth the following hypotheses: (1) English headline – newspapers comprise various textual, discoursal and social features ;(2)the model of analysis is best suited for the current study.To achieve the aims and verify the hypotheses, a critical discourse analysis approach is used represented by Fairclough's socio-cultural approach (2001).The present study has examined the use of

The calibration of a low-speed wind tunnel (LSWT) test section had been made in the present work. The tunnel was designed and constructed at the Aerodynamics Lab. in the Mechanical Engineering Department/University of Baghdad. The test section design speed is 70 m/s. Frictional loses and uniformity of the flow inside the test section had been tested and calibrated based on the British standards for flow inside ducts and conduits. Pitot-static tube, boundary layer Pitot tube were the main instruments which were used in the present work to measure the flow characteristics with emphasize on the velocity uniformity and boundary layer growth along the walls of the test section. It is found that the maximum calibrated velocity for empty test s

The calibration of a low-speed wind tunnel (LSWT) test section had been made in the present work. The tunnel was designed and constructed at the Aerodynamics Lab. in the Mechanical Engineering Department/University of Baghdad. The test section design speed is 70 m/s. Frictional loses and uniformity of the flow inside the test section had been tested and calibrated based on the British standards for flow inside ducts and conduits. Pitot-static tube, boundary layer Pitot tube were the main instruments which were used in the present work to measure the flow characteristics with emphasize on the velocity uniformity and boundary layer growth along the walls of the test section. It is found that the maximum calibrated velocity for empty test sect

Evaluation of Dot. ELISA test for Diagnosis Visceral Leishmaniasis in Infected Children