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Experimental and Theoretical Study for Performance Enhancement of Air Solar Collectors by Using Different Absorbers
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An experimental and theoretical study has been done to investigate the thermal performance of different types of air solar collectors, In this work air solar collector with a dimensions of (120 cm x90 cm x12 cm) , was tested under climate condition of  Baghdad city with a (43° tilt angel)  by using  the absorber plate (1.45 mm thickness, 115 cm height x 84 cm width), which was manufactured from iron painted with a black matt.

The experimental test deals with five types of absorber:-

 Conventional smooth flat plate absorber , Finned absorber , Corrugated absorber plate, Iron wire mesh on absorber And matrix of porous media  on absorber .

The hourly and average efficiency of the collectors were investigated for three values of mass flow rates (0.016 kg/s to 0.027 kg/s) for each type of collector and then the porosity for the last collector type was tested by changing the porosity of porous media.

A typical air solar collector has been studied Theoretically to build a standard software for testing any type of air solar collectors with local weather data .

From the experimental study  it can be seen  by using some obstacle material to the air flow (fins, corrugated absorber plate, iron wire mesh porous media on the absorber) could be enhanced the efficiencies not less than 4 %  for  finned type and 8 % for corrugated and 25 % for mesh and 30  %  for porous media comparing with flat plate (smooth) collector .

Theoretically, the results showed that the collector with high convention heat transfer coefficient porous media has high  hourly efficiency about (η = 56 %) and iron wire mesh on absorber ( η = 52 % ), on the other  side the minimum  performance occurred in the  flat plate absorber  (η = 28  %).

Comparison of results reveals that the theoretical predictions agree reasonably well with experimental results. And the difference between the theoretical   and experimental efficiency in general was between (1─ 15 %).

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Publication Date
Sun Jul 01 2018
Journal Name
قضايا سياسية
نظرية النخبة في الفكر السياسي الغربي المعاصر
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تعد ظاهرة النخبة من اهم الموضوعات التي يعنى بها دارسو العلوم السياسية، اذ تشكل هذه الظاهرة محور نشاطات الجماعة السياسية، وبالرغم من تباين النظريات المتعلقة بتفسير وجود هذه الظاهرة ونشأتها، فان هناك اتفاقا على ارتباط هذه الظاهرة بتوزيع القوة داخل المجتمع الانساني فبعد ان كانت هذه الكلمة )النخبة( تستخدم في القرن السابع عشر لوصف سلع ذات تفوق معين امتد استعمالها فيما بعد ليشمل الاشارة الى فئات اجتماعية متفوقة ك

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Publication Date
Thu Jul 28 2022
Journal Name
Mechanics Based Design Of Structures And Machines
Experimental investigation on the damping characteristics in dry and saturated sands
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Publication Date
Mon Nov 01 2010
Journal Name
Iraqi Journal Of Physics
Streams and plasma parameters experimental studies in He-CO gas mixtures
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DC glow discharges were generated between a thin cylindrical anode and a flat cathode, streamers are thought to propagate by photo-ionization; the parameters of photo-ionization depend on the He: CO ratio. Therefore we study streamers in He ( 90%, 80% and 70% ) with (10%, 20% and 30%) CO respectively. The streamer diameter is essentially the change by increase for similar voltage and pressure in all He-CO mixtures.

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Publication Date
Sat Dec 31 2016
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Investigation of Binary Solvents Performance for Regeneration of Iraqi 15W- 40 Waste Lubricant
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The aim of this study was to investigate the effectiveness of binary solvent for regeneration of spent lubricating oil by extraction-flocculation process. The regeneration was investigated by bench scale experiments by using locally provided solvents (Heavy Naphtha, n-Butanol, and iso-Butanol). Solvents to used oil, mixing time, mixing speed and temperatures were studied as operating parameters. The performance on three estimated depended key parameters, namely the percentage of base oil recovered (Yield), percent of oil loss (POL), and the percent of sludge removal (PSR) were used to evaluate the efficiency of the employed binary solvent on extraction process. The best solvent to solvent ratio for binary system were 30:70 for Heavy Naph

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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
Study the Effect of solvent on the Optical Properties Performance of active polymeric laser media
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The paper include studies the effect of solvent of dye doped in polymeric laser sample which manufactured in primo press way, which is used as an active (R6G) tunable dye lasers. The remarks show that, when the viscosity of the solvent (from Pure Water to Ethanol), for the same concentration and thickness of the performance polymeric sample is increased, the absorption spectrum is shifts towards the long wave length (red shift), & towards short wave length (blue shift) for fluorescence spectrum, also increased the quantum fluorescence yield. The best result we obtained for the quantum fluorescence yield is (0.882) with thickness (0.25mm) in Ethanol solvent in concentration (2*10-3mole/liter), while when we used the Pure Water as a solvent,

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Publication Date
Tue Oct 30 2001
Journal Name
3rd. Jordanian Civil Engineering Conference ,29-31 Oct.2001. 2001
The Use of the F.E.M. to Study the Performance of Stone Columns in Soft Soil
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In this paper, the penetration of the stone column was investigated in order to get the minimum length of the stone column above which the increase in length has little advantage. The effect of using different materials in column are also studied. The material used is granular of different angle of internal friction (). The results of the investigation indicated that the effect of stone column remains constant when the ratio of the thickness of the soft clay layer to the stone column’s diameter is more than 15. The results also indicated that a pronounced effect is obtained when the angle of internal friction of the stone column material is increased.

Publication Date
Sun Jun 01 2008
Journal Name
Baghdad Science Journal
Study the Effect of thickness on the Optical Properties Performance of active polymeric laser media
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The paper include study the effect thickness of the polymeric sample which is manufactured by thermo press way. The sample was used as an active tunable R6G laser media. The remarks show that, when the thickness of the samples is increased, with the same concentration, the spectrum will shift towards the short wavelength, & the quantum fluorescence yield will increased. The best result we obtained for the quantum fluorescence yield is (0.68) at the sample, with thickness (0.304mm) in Ethanol solvent, while when we used the Pure Water as a solvent, we found that the best quantum fluorescence yield is (0.63) at (0.18mm) thickness of the sample.

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Publication Date
Sat Aug 31 2019
Journal Name
Iraqi Journal Of Physics
A Study of the Spectroscopic Performance of Laser Produced CdTe(x):S(1-x) Plasma
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Abstract

In this work, the plasma parameters (electron temperature (Te), electron density( ne), plasma frequency (fp) and Debye length (λD)) have been studied by using the spectrometer that collect the spectrum of Laser produce CdTe(X):S(1-X) plasma at X=0.5 with different energies. The results of electron temperature for CdTe range 0.758-0.768 eV also the electron density 3.648 1018 – 4.560 1018 cm-3  have been measured under vacuum reaching 2.5 10-2 mbar .Optical properties of CdTe:S were determined through the optical transmission method using ultraviolet visible spectrophotometer within the r

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Publication Date
Mon May 01 2023
Journal Name
Journal Of Molecular Liquids
On the influence of hydrocarbons solvents on the inhibition efficiency of some organic corrosion inhibitors: Theoretical and validation studies
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Publication Date
Sun May 15 2016
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
Population growth and the culture of consumption A field study in the city of Arbil.: Population growth and the culture of consumption A field study in the city of Arbil.
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research objectives to:
1. identify the social, economic and cultural factors affecting consumption.
2. detect the consumption culture among the population in the city of Erbil.
3. Identify the GATT consumer protection and rights.
The most important results:
1. that there is variation in the answers of respondents about keep up with modernity in the basic consumption (necessary), it swallowed the proportion of yes answers about keep up with modernity in food consumption (72%), and is an indication of growing consumer awareness of the individual in the side of nutrition. The clothing on the side of the proportion of yes answers amounted to (85%), in the health field note that the percentage of yes answers (83%), who are abr

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