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Improving the melting performance in a triple-pipe latent heat storage system using hemispherical and quarter-spherical fins with a staggered arrangement
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This study aims to evaluate the melting characteristics of a phase change material (PCM) in a latent heat storage system equipped with hemispherical and quarter-spherical fins. A vertical triple-pipe heat exchanger is used as the PCM-based heat storage unit to improve the melting performance compared with a double-pipe system. Furthermore, the fins are arranged in inline and staggered configurations to improve heat transfer performance. For the quarter-spherical fins, both upward and downward directions are examined. The results of the system equipped with novel fins are compared with those without fins. Moreover, a fin is added to the heat exchanger’s base to compensate for the natural convection effect at the bottom of the heat exchanger. Considering similar fin volumes, the results show that the system equipped with four hemispherical fins on the side walls and an added fin on the bottom wall has the best performance compared with the other cases with hemispherical fins. The staggered arrangement of the fins results in a higher heat transfer rate. The downward quarter-spherical fins with a staggered configuration show the highest performance among all the studied cases. Compared with the case without fins, the heat storage rate improves by almost 78% (from 35.6 to 63.5 W), reducing the melting time by 45%.

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Publication Date
Mon Sep 23 2019
Journal Name
Baghdad Science Journal
Representation of Algebraic Integers as Sum of Units over the Real Quadratic Fields
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In this paper we generalize Jacobsons results by proving that any integer  in   is a square-free integer), belong to . All units of  are generated by the fundamental unit  having the forms

our generalization build on using the conditions

This leads us to classify the real quadratic fields  into the sets  Jacobsons results shows that  and Sliwa confirm that  and  are the only real quadratic fields in .

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Publication Date
Sun Apr 04 2010
Journal Name
Journal Of Educational And Psychological Researches
Translation & Adaptation of(Patterns) & (Assembly) Scales of The Flanagan Aptitude Classification Tests (FACT)
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The Flanagan Aptitude Classification Tests (FACT) assesses aptitudes that are important for successful performance of particular job-related tasks. An individual's aptitude can then be matched to the job tasks. The FACT helps to determine the tasks in which a person has proficiency. Each test measures a specific skill that is important for particular occupations. The FACT battery is designed to provide measures of an individual's aptitude for each of 16 job elements.

The FACT consists of 16 tests used to measure aptitudes that are important for the successful performance of many occupational tasks. The tests provide a broad basis for predicting success in various occupational fields. All are paper and pen

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Publication Date
Sun Jun 05 2011
Journal Name
Baghdad Science Journal
Toxicity effects of some heavy metals on the growth of alga Scenedesmus dimorphus
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The toxicity effect of some heavy metals (Lead, Cadmium, Copper, and Zinc) on the growth of alga Scenedesmus dimorphus which belongs to the Division of Chlorophyta was studied and depended on the total cell number . The growth rate and doubling time were also calculated accordingly in present of absent of the the heavy metals . There were differences in toxic effects of the metals (p<0.05) . The growth was decreased gradually with alga when exposured to Lead at 15,20 and 25 mg/l in comparison with the control , mean while 30 mg/l caused an acute decrease in growth . Treating the alga with 0.05,0.1,0.5 mg/l concentration of Cadmium the number of cells decreased while at 1 mg/l the effect was more pronounced . As for Copper the conc

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Publication Date
Sun Mar 01 2009
Journal Name
Csasc English Ver., 4th Scientific Conference; College Of Science; Babylon University
Effect of NaCl on the cresyl violet( CV) –sodium dodecyl sulphate (SDS) complex
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Abstract: In this research we study the of added NaCl with concentration (0.2, 0.02)M on the spectral of cationically charged dye (cresyl violet) and anionically charged surfactant (sodium dodecyl sulphate) with different concentration, the result show two peaks appearance the first attributed to micelle and the other formation of dye surfactant complex, in addition to the increase in the quantum efficiency of emission spectrum and shifted toward long wavelength (λmax=692.5nm-626nm).

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
the effect of organic solvent extracts of callistemon citrinns leaves on some biological
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In this study, evaluate the impact of organic extracts of leaf butterfly Albzl in some aspects of life has been affected performance ratio destruction of eggs increased by 0.8% extract Alorat ethanol solvent, ethyl acetate and hexane, respectively ..

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Publication Date
Sun Jun 27 2021
Journal Name
Journal Of The College Of Education For Women
Morphometric Characteristics of the Aziana Valley Basin: هبه محمد فياض, اسحق صالح العكام
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The present study aims at examining quantitatively the morphometric characteristics of Iziana Valley basin that is located in the northern part of Iraq; particularly in south of Erbil Governorate. This basin is considered one of the small sub-basins where its valleys run on formations of the Triple and Quadrant Ages, which are represented by the Bay Hassan formations, and the sediments and mixed sediments of the cliffs, respectively. The area of ​​the Iziana basin amounts to (36.39 km2) whereas the percentage of its rotation reaches (0.17); a low percentage, which indicates that the basin diverges from the circular to the rectangular shape. The value of the elongation ratio of the basin reaches (0.38) while the terrain rat

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Publication Date
Sun Mar 30 2008
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Pyrolysis of High-density Polyethylene for the Production of Fuel-like Liquid Hydrocarbon
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Pyrolysis of high density polyethylene (HDPE) was carried out in a 750 cm3 stainless steel autoclave reactor, with temperature ranging from 470 to 495° C and reaction times up to 90 minute. The influence of the operating conditions on the component yields was studied. It was found that the optimum cracking condition for HDPE that maximized the oil yield to 70 wt. % was 480°C and 20 minutes. The results show that for higher cracking temperature, and longer reaction times there was higher production of gas and coke. Furthermore, higher temperature increases the aromatics and produce lighter oil with lower viscosity.

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Publication Date
Tue Dec 31 2019
Journal Name
Journal Of Economics And Administrative Sciences
“The Strategic Partnership to Strategic Leadership of Upgrade Higher Education Quality (Global Perspective)”
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The higher education has become an enterprise integrate system that described as knowledge society, the essential part in its electronic and virtual format in the shadow of globalization challenges with its various dimensions . Until the logical ryles aboat a strategic partnership between the Iraqi higher education establishments and their international equivalent ones Strategic windows should be invested for the purpose of enhancing the quality of higher education in a sustainable way. This forms a challenge before the international education leaders on the social, operational and establishment's level to determinte knowledge gap, observing, diagnosing and processing in the present and future, e

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Publication Date
Sat Dec 01 2012
Journal Name
Iraqi Journal Of Physics
The effect of additive carbon nano tube on optical properties of epoxy resin
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In this work, MWCNT in the epoxy can be prepared at room temperature and thickness (1mm) at different concentration of CNTs powder. Optical properties of multi-walled carbon nanotubes (CNTs) reinforced epoxy have been measured in the range of (300-800)nm. The electronic transition in pure epoxy and CNT/epoxy indicated direct allowed transition. Also, it is found that the energy gap of epoxy is 4.1eV and this value decreased within range of (4.1-3.5)eV when the concentration of CNT powder increased from (0.001-0.1)% respectively.
The optical constants which include (the refractive index (n), the extinction coefficient (k), real (ε1) and imaginarily (ε2) part of dielectric constant calculated in the of (300-800)nm at different concent

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Publication Date
Sun Mar 01 2020
Journal Name
Baghdad Science Journal
The Biofilm Inhibitory Potential of Compound Produced from Chlamydomonas reinhardtii Against Pathogenic Microorganisms
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Microalgae present much usefulness for antimicrobial research because of its enormous biodiversity and rapid growth rate. From this study results it is reaveled that Chlamydomonas reinhardtii were isolated from a pond of water in the province of Diwaniyah. The culture supernatants were obtained when extracted with methanol solvent. Antimicrobial activity of extracts was tested for pathogens, and the best inhibition zone obtained was against Candida albicans (32mm), S.aureus (15mm), and to E.coli (9mm). While it showed no effect against both S.epidermidis and Klebsiella spp. Biofilm was formed by all tested isolates with differences in its strength formation. The C. reinhardtii

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