Preferred Language
Articles
/
joe-357
Study Effect of Central Rectangular Perforation on the Natural Convection Heat Transfer in an Inclined Heated Flat Plate
...Show More Authors

Anumerical solutions is presented to investigate the effect of inclination angle (θ) , perforation ratio (m) and wall temperature of the plate (Tw) on the heat transfer in natural convection from isothermal square flat plate up surface heated (with and without concentrated hole). The flat plate with dimensions of (128 mm) length × (64 mm) width has been used five with square models of the flat plate that gave a rectangular perforation of (m=0.03, 0.06, 0.13, 0.25, 0.5). The values of angle of inclination were (0o, 15o 30o 45o 60o) from horizontal position and the values of wall temperature (50oC, 60 oC, 70 oC, 90 oC, 100oC). To investigate the temperature, boundary layer thickness and heat flux distributions; the numerical computation is carried out using a very efficient integral method to solve the governing equation. The results show increase in the temperature gradient with increase in the angle of inclination and the high gradient and high heat transfer coefficients located in the external edges of the plate, for both cases: with and without holed plate. There are two separation regions of heat transfer in the external edge and the internal edges. The boundary layer thickness is small in the external edge and high in the center of the plate and it decreases as the inclination angle of plate increases. Theoretical results are compared with previous result and it is found that the Nusslet numbers in the present study are higher by (22 %) than that in the previous studies. And the results show good agreement in range of Raleigh number from 105 to 106.

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Nov 08 2022
Journal Name
V. International Scientific Congress Of Pure, Applied And Technological Sciences
The effect of background vacuum pressure on the length of gas discharge plasma by using Aluminum electrodes
...Show More Authors

Length of plasma generated by dc gas discharge under different vacuum pressures was studied experimentally. The cylindrical discharge tube of length 2m was evacuated under vacuum pressure range (0.1-0.5) mbar at constant external working dc voltage 1500V. It was found that the plasma length (L) increased exponentially with increasing of background vacuum air pressure. Empirical equation has been obtained between plasma length and gas pressure by using Logistic model of curve fitting. As vacuum pressure increases the plasma length increases due to collisions, ionizations, and diffusions of electrons and ions.

Publication Date
Fri Jun 01 2012
Journal Name
Advances In Materials Physics And Chemistry
The Effect of Zn Concentration on the Optical Properties of Cd10–xZnxS Films for Solar Cells Applications
...Show More Authors

ABSTRACT:In this paper, Cd10–xZnxS (x = 0.1, 0.3, 0.5) films were deposited by using chemical spray pyrolysis technique, the molar concentration precursor solution was 0.15 M/L. Depositions were done at 350°C on cleaned glass substrates. X-ray dif- fraction technique (XRD) studies for all the prepared film; all the films are crystalline with hexagonal structure .The optical properties of the prepared films were studied using measurements from VIS-UV-IR spectrophotometer at wave- length with the range 300 - 900 nm; the average transmission of the minimum doping ratio (Zn at 0.1%) was about 55% in the VIS region, it was decrease at the increasing of Zn concentration in the CdS films, The band gap of the doped CdS films was varied as 3.7, 3

... Show More
Preview PDF
Publication Date
Thu Jan 15 2015
Journal Name
مجلة كلية التربية-المؤتمر العلمي التخصصي لكلية التربية
Investigation the Effect of Irradiation by Gamma-Ray on the Structural and Optical Properties of (CIGS) Films
...Show More Authors

Publication Date
Fri Mar 31 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
The Effect of some Variables on the Formulation of Captopril as Tablets Shaymaa Nazar Al – Sammarrai
...Show More Authors

Captopril is an angiotensin converting enzyme inhibitor (ACEI) used to treat hypertension,
congestive heart failure, and myocardial infraction.
The only dosage form available for captopril is the plain tablet in strength of 12.5,25,50 and 100mg
tablet.
This investigation is concerned with factors affecting the formulation of captopril as a plain
tablet dosage form of 50mg. Many trials were made to prepare satisfactory tablets for the drug by
using wet – granulation methods with various additives. It was found that poly vinyl pyrrolidone
(P.V.P.) as binder gave the most satisfactory tablets. At the same time a shorter disintegrantion time
and slower dissolution rate were obtained with the addition of starch

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Mar 01 2008
Journal Name
Al-khwarizmi Engineering Journal
Effect Of Polar Component(1-Propanol) On The Relative Volatility Of The Binary System N-Hexane - Benzene
...Show More Authors

Vapor-liquid equilibrium data are presented for the binary systems n-hexane - 1-propanol, benzene - 1-propanol and n-hexane – benzene at 760 mm of mercury pressure. In addition ternary data are presented at selected compositions with respect to the 1-propanol in the 1-propanol, benzene, n-hexane system at 760 mmHg. The results indicate the relative volatility of n-hexane relative to benzene increases appreciably with addition of 1-propanol.

View Publication Preview PDF
Publication Date
Thu Dec 01 2016
Journal Name
Journal Of Engineering
Analytical and Experimental Investigation for the Effect of Air Injection Angle on the Performance of Airlift Pump
...Show More Authors

The effect of air injection angle on the performance of airlift pump used for water pumping has been studied analytically and experimentally. An airlift pump of dimensions 42mm diameter and 2200 mm length with conventional and modified air injection device was considered. A modification on conventional injection device (normal air-jacket type) was carried out by changing injection angle from 90  (for conventional) to 45  and 22.5  (for modified). Continuity and one-dimensional momentum balance for the flow field with basic principle of two-phase flow and expressions of slip ratio and friction factor as function of flow rates were formulated. The analytical and experimental investigations were carried out f

... Show More
View Publication Preview PDF
Publication Date
Sun Jan 17 2021
Journal Name
Academic Journal Of Interdisciplinary Studies
Employees Retention Strategy and its Impact on Organizational Memory: An Exploratory Research for the opinion of Faculty Members at Private Colleges on Baghdad
...Show More Authors

The research aims to determine the impact of employees’ retention strategy on organizational memory. This research is historical, descriptive, and analytical. The sample consists of 158 faculty members in five private colleges in Baghdad. The technique used to analyze the data is SEM (Structural Equation Modeling), and SPSS (Statistical Package for the Social Sciences). The research concludes that the employees retaining strategy plays a vital role in retaining employees and hence maintains organizational memory. The findings and recommendations of this research assure the administrations of private colleges that employees retention strategy play a vital role in retaining its employee and hence maintains organizational memory. T

... Show More
View Publication
Scopus (3)
Crossref (7)
Scopus Crossref
Publication Date
Thu Oct 18 2018
Journal Name
Journal Of Economics And Administrative Sciences
Effect of Attitudes in the ethics of the public job of the individual
...Show More Authors

Attitude is an important subject that has attracted researchers and thinkers in organizational theory and organizational behavior because of its great importance in various field studies. Field evidence suggests that individuals in their daily lives or careers respond to specific events through a set of internal tendencies Internal tendencies are negative or positive and systematic. These trends tend to be invisible, not limited to certain boundaries, and involve a significant number of individuals within organizations or society.

 The research aims to identify the impact of trends in the ethics of public service workers for individuals, through a sample of (72) doctors and (60) administrative staff

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Jun 15 2017
Journal Name
Journal Of Baghdad College Of Dentistry
Anti-Microbial Effect Of Different Time’sexposureofozonized Gas And Ozonized Water Onperiodontalpathogens (In Vitro Study)
...Show More Authors

Background: the oral cavity is consider to be an open ecosystem, with the balance between the microorganism’s entrance and the defenses of the host. The initiation of periodontitis has been associated with restricted kinds of anaerobic bacteria, such as Aggregatibacter actinomycetemcomitans (A.a) and Porphyromonas gingivalis (P.g) in plaque subgingivally. Ozone has a biological effects on bacteria due to oxidation of bio-molecules and its toxins. The aim is to determine and compare the antimicrobial effect of gaseous ozone and ozonized water on the growth of isolated anaerobic bacteria (A.a and P.g) when exposed to different time intervals. Materials and methods:This experiment is done byozone generator OLYMPIC- III(600mg/hr) to gene

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Jun 04 2017
Journal Name
Baghdad Science Journal
Levels of Serum Lipid profile and Kidney Function Tests in Iraqi Hypertensive Patients: Duration Effect Study
...Show More Authors

Hypertension is one of the leading causes of the global burden of disease, which causes serious health problems. The aim of this study is to investigate the lipid profile levels in sera of Iraqi hypertensive patients by measuring Total cholesterol (TC), triglyceride (TG) and low density lipoproteins (LDL) and kidney function levels by measuring uric acid, urea and creatinine. Seventy five individuals of Iraqi adults (Males) were divided into three groups: 25 hypertensive patients with duration of disease (1-10) year (group 1), 25 hypertensive patients with duration of disease (11-30) year (group 2) and 25 normal individuals as control group (group3). The findings indicate that serum (TC, TG and LDL) levels were significantly elevated (

... Show More
View Publication Preview PDF
Scopus Crossref