In this work, an experimental study has been done to expect the heat characteristics and performance of the forced-convection from a heated horizontal rectangular fins array to air inside a rectangular cross-section duct. Three several configurations of rectangular fins array have been employed. One configuration without notches and perforations (solid) and two configurations with combination of rectangular-notches and circular-perforations for two various area removal percentages from fins namely 18% notches-9% perforations and 9% notches-18% perforations are utilized. The rectangular fins dimensions and fins number are kept constant. The fins array is heated electrically from the base plate with five different magnitudes of power-inputs. Five several air flow velocity into a duct are utilized. The influence of fin geometry, air flow velocity, Reynolds number and the surface heat flux on the heat-performance of forced heat convection have been simulated and studied experimentally. The experimental data indicates that the combination of 18% rectangular-notched and 9% circular-perforated rectangular fins array gave best forced heat performance in terms of average heat transfer coefficient about (25% - 45%) and (7% - 20%) compared than solid and 9% notches with18% perforations fins array respectively. Five empirical correlations to predict the average Nusselt number for the 18% notches with 9% perforations rectangular fins array at wide range of surface heat flux are deduced. The present data are compared with previous works and a good closeness in behavior is noticed.
This study investigates the stomach morphology and histochemistry of Clarias gariepinus. Grossly, the stomach is a J-shaped organ with three distinct regions: cardiac, fundic, and pyloric. Histologically, its wall comprises four layers: mucosa, submucosa, muscularis externa, and serosa. The mucosa exhibits broad longitudinal folds lined by high columnar cells with basal oval nuclei. These cells contain apical mucosubstances that react positively with Periodic Acid Schiff (PAS) stain and negatively with Alcian Blue (AB). Gastric pits result from mucosal invaginations. Glands are present in the fundic and cardiac regions but absent in the pyloric. Oxynticopeptic cells exclusively line the fundic glands. Enteroendocrine cells are distr
... Show MoreThis study investigates the stomach morphology and histochemistry of Clarias gariepinus. Grossly, the stomach is a J-shaped organ with three distinct regions: cardiac, fundic, and pyloric. Histologically, its wall comprises four layers: mucosa, submucosa, muscularis externa, and serosa. The mucosa exhibits broad longitudinal folds lined by high columnar cells with basal oval nuclei. These cells contain apical mucosubstances that react positively with Periodic Acid Schiff (PAS) stain and negatively with Alcian Blue (AB). Gastric pits result from mucosal invaginations. Glands are present in the fundic and cardiac regions but absent in the pyloric. Oxynticopeptic cells exclusively line the fundic glands. Enteroendocrine cells are distr
... Show MoreThe mobile phone is widespread all over the world. This technology is one of the most widespread with more than five billion subscriptions making people describe this interaction system as Wireless Intelligence. Mobile phone networks become the focus of attention of researchers, organizations and governments due to its penetration in all life fields. Analyzing mobile phone traces allows describing human mobility with accuracy as never done before. The main objective in this contribution is to represent the people density in specific regions at specific duration of time according to raw data (mobile phone traces). This type of spatio-temporal data named CDR (Call Data Records), which have properties of the time and spatial indications for th
... Show MoreThe research has designed for studying the relationship between manufacturing strategy and its flexibility under the flexible manufacturing system with their reflection on the competitive environmental performance of the firm. To interpret and tackle the problem, a hypothesis has formulated stating that “ the competitive performance of a firm is interpreted by the manufacturing strategy and flexibility which are derived from the firm and its business strategies under the flexible manufacturing system”. Related literatures with their theoretical dissertations, which enhanced the thoughtful content, have analyzed. An illustrative case study on the flexible manufacturing system at Toyota Motors Corporation working at the g
... Show MoreWadi AL – yabis situated to the north jorden , its extended from Aglon
mountain to the jorden river , the surveying of this valley about 186 KM , and the
highest point in it about 1200 m upon the sea level , the lower point ther under the
sea level . This study lay to appear the historical important and to study the variation
of environment and population which happened in the different periods , in the
beginning the Paleolithic until the later period , and to understand the environment ,
political and economical circumstances , which it can to influenced or limited in
human behavior from choosing , the settlement sits and than ( we could ) knowledge
of living ways and the tools which they used in there living a
Aims current research to identify the mistakes coding contained in the reading first grade. Encoding knew that he had failed in Retrieval or identifying information, the researcher diagnosis of mistakes and presented to a group of teachers first grade and they have an appropriate adjustment and using the percentage shows that the agreement on the mistakes ratio and adjusted researcher recommended a set of proposals and recommendations can work out the future for the advancement of scientific level
This work aims to detect the associations of C-peptide and the homeostasis model assessment of beta-cells function (HOMA2-B%) with inflammatory biomarkers in pregnant-women in comparison with non-pregnant women. Sera of 28 normal pregnant women at late pregnancy versus 27 matched age non-pregnant women (control), were used to estimate C-peptide, triiodothyronine (T3), and thyroxin (T4) by Enzyme-linked-immunosorbent assay (ELISA), fasting blood sugar (FBS) by automatic analyzer Biolis 24i, hematology-tests by hematology analyzer and the calculation of HOMA2-B% and homeostasis model assessment of insulin sensitivity (HOMA2-S%) by using C-peptide values instead of insulin. The comparisons, correlations, regression analysis tests were perfo
... Show MoreAs a result of the exacerbation of the problem of water pollution, research was directed towards studying the treatment using ceramic membranes, which proved to be highly effective in treating all water sources. The research aims to study the possibility of preparing a new type of ceramic membranes from Syrian zeolite that was not previously used in this field. In this research, ceramic membranes were prepared from Syrian raw zeolite in several stages. Zeolite sample was characterized, grinded, mixed with boric acid, pressed to form desks, treated thermally according to experiment program, finally coated with silver nanoparticles. Specifications of prepared membranes were determined according to reference methods, effectiveness of prepar
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