A free convective heat transfer from the inside surface of a uniformly heated vertical circular tube has been experimentally investigated under a constant wall heat flux boundary condition for laminar air flow in the ranges of Ra_L from 6.910⁸ to 510⁹. The effect of the different sections (restrictions) lengths placed at the exit of the heated tube on the surface temperature distribution, the local and average heat transfer coefficients were examined. The experimental apparatus consists of aluminum circular tube with 900 mm length and 30 mm inside diameter (L/D=30). The exit sections (restrictions) were included circular tubes having the same inside diameter as the heated tube but with different lengths of

The heat and mass transfer coefficients of the indirect contact closed circuit cooling tower, ICCCCT, were investigated experimentally. Different experiments were conducted involving the controlling parameters such as air velocity, spray water to air mass flow rate ratio, spray water flow rate, ambient air wet bulb temperature and the provided heat load to investigate their effects on the performance of the ICCCCT. Also the effect of using packing on the performance of the ICCCCT was investigated. It was noticed that these parameters affect the tower performance and the use of packing materials is a good approach to enhance the performance for different operational conditions. Correlations for mass and heat transfer coefficients are pres

Mixed convection heat transfer in a vertical concentric annulus packed with a metallic porous media and heated at a constant heat flux is experimentally investigated with water as the working fluid. A series of experiments have been carried out with a Rayleigh number range from Ra=122418.92 to 372579.31 and Reynolds number that based on the particles diameter of Re_d=14.62, 19.48 and 24.36. Under steady state condition, the measured data were collected and analyzed. Results show that the wall surface temperatures are affected by the imposed heat flux variation and Reynolds number variation. The variation of the local heat transfer coefficient and the mean Nusselt number are presented and analyzed. An empirical

The importance of the research comes from dealing with the problem of lack of traffic awareness, which causes accidents and the occurrence of human and material losses, and the research aims to study the role of satellite channels in forming traffic awareness among the public, and a sample was chosen from Baghdad consisting of (280) individuals, male and female, and used the questionnaire tool. To obtain the data, which included several questions, the results were analyzed statistically and several results were reached, the most important of which is that there is an interest among the public in following traffic programs at a rate of one to two hours to receive information through traffic programs and to identify and apply gener

A land magnetic survey was carried out along regional profile, which is located at the north part of the Iraqi western desert. It starts from al –Qaam City (at north) toward Rutba City (at south) with a total length of 238km. The survey was carried out along the paved road between the two cities, About 113 measuring points were done with inter-station distance of 2 km (for 198 km) and 2 to 5km (for 40km). Two proton magnetometers were used in this survey. One of them is used for base station monitoring, which was fixed as of Salah Aldin field (Akkas). Its readings were used for diurnal corrections. All magnetic measurements were corrected for normal and topographic corrections. The readings were reduced to a certain base level. The resu

This research was conduct to evaluate the cytotoxic effect of exotoxin A (ETA) produced by Pseudomonas aeruginosa on mice in comparison with (phosphate buffer saline (PBS) as a negative control. The effect of the toxin was measured by employing the cytogenetic analysis which included (the mitotic index (MI), chromosomal aberrations (CAs), micronucleus (MN) and sperm abnormalities) parameters. In order to specify the cytotoxic effect of the toxin, three doses of ETA (125, 250 and 500 ng/ml) were used. Results showed that ETA was found to cause a significant decrease in mitotic index (MI) percentage, while significant increase in micronucleus (MN), chromosomal aberrations (CAs) and sperm abnormalities parameters in compression with control wa

Shiranish formation has been divided into two microfacies units: 1-Marly biowacke stone facies 2-Biogenic pack stone facies These microfacies reflected marine deep shelf margin in the upper part of the formation, the lower part was deeper. 238 slides were investigated depending on Mineralogical, compositional and Biological processes, which reflect deep shelf margin at upper part of the formation, but at the lower part open sea environment. The age of the formation is estimated depending on the recognized biostratigraphic zone using the index fossils to be Upper- Middle Maestrichtian.

In this publication, several six coordinate bridged-polymeric metal complexes are reported. The reaction of 4,4`-dipyridine with ethyl chloroacetate in mole ratio of 1:2 gave the multidentate carboxylate ligand bis(N-carboxylatomethyl)-4,4`-dipyridinium). The reaction of the ligand with metal chloride and sodium azide resulted in the formation of the required polymeric complexes. Upon complex formation, the carboxylato ligand behaves as a neutral multidantate species. The mode of bonding and overall geometry of the complexes were determined through physicochemical and spectroscopic methods. These studies revealed octahedral geometry about metal centres and complexes of the general formula [Cr2(L)(N3)4]Cl2.H2O, Na2[Ag2(L)(N3)4].H2O and [M2(L

Find taught dimension aesthetic in the formation of post-modernism, which is one of the themes of aesthetics in the stream of postmodernism, is problematic because of the lack of provisions and fixed values reinforce the concept of beauty, and put done technical plastic in the circle of evaluation and judgment aesthetic, this research as an attempt to reveal the aesthetic concepts that can be drawn from artistic experiments in the formation of post-modernism, through the development of those concepts viable mainstream.
Search contains four chapters: the first chapter includes a general approach to the research, has been showcasing the research problem and the importance of research and goal of Search: detection dimension aesthetic in