Preferred Language
Articles
/
joe-599
Experimental Study of Optimum Chilled Water Distribution Configuration in Air Conditioning Terminal Unit Using RSM Technique
...Show More Authors

The distribution of chilled water flow rate in terminal unit is an important factor used to evaluate the performance of central air conditioning unit. A prototype of A/C unit has been made, which contains three terminal units with a complete set of accessories (3-way valve, 2-way valve, and sensors) to study the effect of the main parameters, such as total water flow rate and chilled water supply temperature with variable valve opening. In this work, 40 tests were carried out. These tests were in two groups, 20 test for 3-way valve case and 20 test for 2-way valve case. These tests were performed at three levels of valve opening, total water flow rate and water supply temperature according to the design matrices established by Design of Experiment (DOE) software 'version 7' with Response surface methodology (RSM) technique. The model was conducted for each case of total heat rate, then checked statistically for adequacy by Analysis of variance (ANOVA), and found good with 95% confidence level. The results showed that the water supply temperature has a significant effect on the total heat rate of two cases. It was found that the optimum solution for maximum total heat rate and minimum flow deviation represented by standard deviation was obtained at 10°C water supply temperature, 5.5 l/min total water flow rate and 70% valve opening. The total heat rate and standard deviation were (890.249 Watt), (0.000513), respectively in three-way valve case and (743.155 Watt), (0.00277), respectively in two-way valve case. Finally, the predicted and experimental results of total heat rate and standard deviation were in agreement with a maximum error of 6.6 % in three-way valve case and 1.4% in two-way valve case.

 

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Thu Dec 31 2015
Journal Name
Al-khwarizmi Engineering Journal
Modeling of Mass Transfer Coefficient in Rotating Biological Contactor with Perforated Discs (RPBC)
...Show More Authors

Abstract

 In order to make an improvement associated with rotating biological contactor (RBC), a new design of biofilm reactor called as Rotating perforated disc biological contactor (RPBC) was developed in which the rotating discs are perforated. The transfer of oxygen from air to wastewater was investigated. Mass-transfer coefficient (KLa)  in the liquid phase was determined by measuring  the rate transfer of oxygen.  A   laboratory scale of (RPBC) consisted of a semicircular trough was used with a working capacity of 40 liters capacity of liquid. Synthetic wastewater was used as a liquid phase, while air was used as a gas phase.

The effects of m

... Show More
View Publication Preview PDF
Publication Date
Tue Feb 01 2011
Journal Name
Biochemical Engineering Journal
Elicitation of Streptomyces coelicolor with E. coli in a bioreactor enhances undecylprodigiosin production
...Show More Authors

View Publication
Scopus (20)
Crossref (15)
Scopus Clarivate Crossref
Publication Date
Fri Feb 08 2019
Journal Name
Iraqi Journal Of Laser
Laser Induced Fluorescence Spectroscopy of Decamethylrhenocene ( - C5 Me5)2 Re in Supersonic Jet
...Show More Authors

In this paper we report the use of supersonic jet laser induced fluorescence (LIF) spectroscopy to facilitate the study of the spectra of some organometallic sandwich compounds particularly the metallocenes. The charge-transfer processes within these compounds, especially ligand to metal charge transfer within decamethylrhenocene ( - C5 Me5)2 Re were of particular interest. The spectrum shows a high degree of structures, indicating that there are several levels populated and these molecules are able to undergo many possible transitions

View Publication Preview PDF
Publication Date
Sun Jun 25 2023
Journal Name
Tikrit Journal Of Pure Science
Chemical comparison and Trichomes types of Salvia species growing in Anbar Governorate – Iraq
...Show More Authors

The trichomes and chemical composition of three species of the genus Salvia wild-grown (Salvia lanigera, Salvia spinosa) and cultured (Salvia officinalis) were studied in the Anbar governate, the chemical components of the stem and leaves were studied by Gas chromatography–mass spectrometry(GC-MS), in addition to studying the trichomes of the epidermis in the stem and leaves (upper and lower epidermis) by Light microscope. Important differences appeared to us in the chemical study, where it was found that some compounds were found in species without others, which gives them taxonomic importance, also, the trichomes were important in distinguishing the studied species, the species S. spinosa was distinguished by the presence of gla

... Show More
View Publication
Crossref
Publication Date
Sat Mar 30 2013
Journal Name
College Of Islamic Sciences
 The responses of the army overseer to the grammarians in the preposition section
...Show More Authors

This is a contextual study in face and isotope science, and I have made it in one of the terms faces and isotopes, which is the word (bad). Quranic also, and that is at every aspect they mentioned.
The nature of the research required that it be divided into three sections:
The first topic: I singled it out to show the types of contextual connotations.
- The second topic: I singled it out to define the word bad and its meaning.
- The third topic: I devoted it to the study of the word bad and explaining the significance of the Quranic context on the additional meaning and the original meaning.
Conclusion: It mentioned the most important results, which are:
1- The significance of the Quranic context is one of the most impo

... Show More
View Publication Preview PDF
Publication Date
Wed Jan 01 2025
Journal Name
Aip Conference Proceedings
Analysis of wake effects induced by heavy ion tracks in titanium nitride ceramic
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Thu Jun 29 2023
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Synthesis of Novel Porphyrin Derivatives and Investigate their Application in Sensitized Solar Cells
...Show More Authors

Solar energy has significant advantages compared to conventional sources such as coal and natural gas, including no emissions, no need for fuel, and the potential for installation in a wide range of locations with access to sunlight. In this investigation, heterocyclic derivatives were synthesized from several porphyrin derivatives (4,4',4",4"'-(porphyrin-5,10,15,20-tetrayl) tetra benzoic acid) compound (3), obtained by reaction Pyrrole with 4-formyl benzoic acid. Subsequently, porphyrin derivative-component amides 5a, 5b, and 5c were produced by reacting compound (3) with amine derivatives at a 1:4 molar ratio. These derivatives exhibited varying sensitivities for utilization in solar cells, with compound 5a displaying the highest power

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jul 02 2017
Journal Name
Journal Of Educational And Psychological Researches
Complex thinking among secondary school student in accordance with the views of lipman
...Show More Authors

The current study has sought to identify the levels of the compound thinking among secondary school students basing and relying on the opinions of Lipman who sees that the compound thinking consists of creative thinking and critical thinking, In accordance with this point of view, researchers have resorted to build scale of the critical thinking in its final form of (28) item additionally to the adoption of Torrance for the creative thinking which was translated by sayed. Khairallah in 1981 after confirming psychometric Properties Of both scales and then collect scores of both scales and be the final score represented the level of the compound thinking that has been shown by the results of secondary school students they have no skill of

... Show More
View Publication Preview PDF
Publication Date
Thu Sep 15 2022
Journal Name
Al-academy
Color diversity and its aesthetic value in the designs of children's fashion fabrics
...Show More Authors

Fabric design is one of the arts in which humans participate functionally and aesthetically. Researching its design aspects is an important goal, especially after taking technical developments to cover many of its fields. Modern designs emphasize the importance of preparing designs and implementing them according to the child’s ability, inclinations and desires (mental, psychological and emotional). ), as the child is the real focus of the design idea, and the designer has paid most of his attention to the requirements and needs of this stage (childhood stage) because of its importance in the life of society, as he focused his attention on implementing designs that could achieve stability and stability in the child’s psyche through s

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Jan 01 2022
Journal Name
Geotechnical Engineering And Sustainable Construction
Numerical Modelling of Surface Runoff in Watershed Areas Related to Bahr AL-Najaf
...Show More Authors

View Publication
Scopus (1)
Scopus Crossref