Preferred Language
Articles
/
joe-237
Absorber Diameter Effect on the Thermal Performance of Solar Steam Generator
...Show More Authors

In this work, a convex lens concentrating solar collector is designed and manufactured locally by using 10 convex lenses (concentrator) of a diameter 10cm and one Copper absorber tube of a diameter 12.5mm and 1mm in thickness 1m length. Two axes manual Tracking system also constructed to track the sun continuously in two directions. The experiments are made on 17th of May 2015 in climatic conditions of Baghdad. The experimental data are fed to a computer program to solve the thermal performing equation, to find efficiency and actual useful energy. Then this data is used in numerical CFD software for three different absorber diameters (12.5 mm, 18.75 mm and 25 mm). From the results that obtained the maximum thermal efficiency for the collector of diameter 12.5mm equal to 82.3% is higher than that for the collector of 18.75 mm and 25 mm diameter. The maximum outlet temperature is found equal to (105C, 93.9C and 83.5C) for collector absorber diameter equal to (12.5 mm, 18.75mm and 25 mm) respectively. The maximum mass flow rate 0.53 kg/hr when the solar radiation intensity equal to 899 W/m2. The all-day collector efficiency varies with diameter and reaches to maximum value of (77.9%, 61.4% and 52.8) for collector diameter equal to (12.5 mm, 18.75mm and 25 mm) respectively.

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun May 08 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The effect of the relationship between the internal auditor and the external auditor on the Earnings quality in Iraqi companies listed in the Iraqi Stock Exchange
...Show More Authors

The changes that have occurred in the business environment and scientific and technological progress, as well as the complexity of administrative problems resulting from its practice of various activities, have led to an increase in the responsibilities entrusted to it, and for the purpose of achieving its strategic objectives, which has made the pillars of corporate governance an inevitable matter required by the nature of modern scientific management of the governorate, the success that companies seek is based on the fertile environment and the dialectical relationship between the individual and the company, and to achieve this success there must be a compatible and harmonious audit environment between the internal and external

... Show More
View Publication Preview PDF
Publication Date
Sun Mar 31 2013
Journal Name
European Scientific Journal, Esj
EFFECT OF SALT CONTENT ON TOTAL AND MATRIC SUCTION OF UNSATURATED SOILS
...Show More Authors

Soils located above the groundwater table are generally unsaturated and possess negative pore-water pressures. A soil-water characteristic curve (SWCC) that relates the water content of a soil to matric suction is an important relationship for the unsaturated soil mechanics. The SWCC essentially shows the ability of an unsaturated soil to retain water under various matric suctions. The filter paper method is a soil suction measurement technique. Soil suction is one of the most important parameters describing the moisture condition of unsaturated soils. The measurement of soil suction is crucial for applying the theories of the engineering behavior of unsaturated soils.In this paper, three soil samples were collected from three sites within

... Show More
View Publication Preview PDF
Publication Date
Mon Jun 15 2020
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of plasma treatment on some surface properties of acrylic resin polymer
...Show More Authors

Background: Polymer surfaces usually present problems in bonding and finishing due to their low hydrophilicity. The aim of this study is to investigate the effect of plasma treatment with the use of two types of gases (oxygen and argon) on surface roughness, and chemical surface properties of acrylic resin denture base polymer material. Materials and Methods: Three heat cured acrylic resin specimens of (2*8*30 mm) dimensions were prepared for each test carried out in this study. Two tests were conducted, surface roughness test and chemical surface analysis test. Results: Application of plasma treatment increased surface roughness for both oxygen and argon plasma treated acrylic resin specimen groups compared with control untreated group,

... Show More
View Publication Preview PDF
Scopus (3)
Crossref (1)
Scopus Crossref
Publication Date
Sun Mar 04 2012
Journal Name
Baghdad Science Journal
Effect of Temperature on Reliability and Degradation of 0.63?m Laser Diode
...Show More Authors

The reliability of optical sources is strongly dependent on the degradation and device characteristics are critically dependent on temperature. The degradation behaviours and reliability test results for the laser diode device (Sony-DL3148-025) will be presented .These devices are usually highly reliable. The degradation behaviour was exhibited in several aging tests, and device lifetimes were then estimated. The temperature dependence of 0.63?m lasers was studied. An aging test with constant light power operation of 5mW was carried out at 10, 25, 50 and 70°C for 100hours. Lifetimes of the optical sources have greatly improved, and these optical sources can be applied to various types of transmission systems. Within this degradation range,

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Wed Apr 01 2020
Journal Name
Indian Journal Of Ecology,
Effect of foliar spraying with bilirubin on growth traits of wheat varieties
...Show More Authors

Scopus (4)
Scopus
Publication Date
Fri Sep 15 2023
Journal Name
Bionatura
Effect of Freezing On Some Morphometric Features of Planiliza Abu ( Hekel,1843)
...Show More Authors

The present study attempts to determine the effect of freezing for different periods on preserved bodies of fish in the laboratory to keep for the research and diagnosis of taxonomic studies and not for consumption. It also endeavors to identify the effect of freezing on some morphometric features of the preserved bodies of fishes. Planiliza abu fish were used to conduct the present study. Fish were frozen by regular freezing in the home refrigerator freezer with temperatures reaching four degrees centigrade below zero. Freezing time is distributed over four months; biometric measurements of frozen fish have been taken in these periods represented by body total length, Standard length, and Head length in centimeters using a ruler ve

... Show More
View Publication
Scopus Crossref
Publication Date
Mon Dec 18 2017
Journal Name
Al-khwarizmi Engineering Journal
Effect of Magnesium Addition on Corrosion Resistance of Aluminum -17%Silicon Alloy
...Show More Authors

The electrochemical behavior of Al-17%Si alloy is investigated in 3.5wt% NaCl solution. Many alloys with addition of the different wt% magnesium metal of  1wt%, 2%, 3wt% ,4.5wt% ,and 9wt% were prepared by gravity die casting . The microstructures of prepared alloys were examined by optical and SEM microscopes. Corrosion behavior was investigated by using potentiostat instrument under static potentials test and corrosion current was recorded to determine corrosion resistance of all prepared samples. It was found that the addition of Mg metal improves the corrosion resistance of Al-17%Si alloy in 3.5%NaCl solution. The alloy containing 1%Mg shows less corrosion rate than the others while the alloys containing 4.5%Mg, 9%Mg content have

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Wed Jun 01 2022
Journal Name
Civil And Environmental Engineering
Effect of Alkali - Activated Natural Pozzolan on Mechanical Properties of Geopolymer Concrete
...Show More Authors

As an alternative to Ordinary Portland Cement (OPC), the alkali-activated binders have been developed with better technical characteristics and more extended durability. The Alkali-Activated Iraqi Natural Pozzolans (AANP) could produce geopolymer cementation building materials and make them ecologically acceptable. The primary advantage of geopolymer cement is that it has a lower environmental effect that contributes to it. The engineering characteristics of geopolymer concrete produced using activated Iraqi natural Pozzolan are summarized in this research. The mechanical properties, modulus of elasticity, and ultrasonic pulse velocity of various concrete mixes were determined via experimental study. The impact of essential variables like w

... Show More
View Publication
Scopus (19)
Crossref (19)
Scopus Clarivate Crossref
Publication Date
Mon Jul 01 2024
Journal Name
Iop Conference Series: Earth And Environmental Science
Effect of Nitrogen and Sulfur Fertilizers on Growth and Yield of Canola
...Show More Authors
Abstract<p>For the purpose of determining the impact of three levels of nitrogen fertilizer (0, 60, and 120 kg.ha<sup>-1</sup>) and sulfur fertilizer (0, 40, and 60 kg.ha<sup>-1</sup>) on production and growth indicators (number of leaves, number of branches, chlorophyll pigments, and fresh and dry weights), a field experiment was carried out during the winter season (2021/2022) in the fields of Al-Diwaniyah Province, Ministry of Agriculture, Diwaniyah Agriculture Directorate, Al-Nouriyah Forest Division. Means were compared using the least significant difference test (LSD) at a 0.05 level of probability. In a factorial experiment employing a wholly randomized block design wi</p> ... Show More
View Publication
Scopus (1)
Crossref (1)
Scopus Crossref
Publication Date
Tue Jun 01 2021
Journal Name
International Journal Of Agricultural And Statistical Sciences
Effect of phosphorous and amino acid on growth and yield of pea
...Show More Authors

Scopus (5)
Scopus