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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
Sat Apr 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Measuring the level of unemployment in Iraq by using the user / product schedule for 2010
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Economic performance is one of the most important indicators of economic activity and with the performance of the economy progress varied sources of output and increase economic growth rates and per capita national income, and to recover the business environment and increase investment rates and rising effectiveness of the financial and monetary institutions and credit market. Which leads to increased employment rates and reducing unemployment rates and the elimination of many of the social problems and improve the average per capita income as well as improve the level of national income.

The input / output tables is a technique mathematical indicates economic performance

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Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Engineering
Using a New Modification on Wind Turbine Ventilator for Improving Indoor Air Quality
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This paper describes a newly modified wind turbine ventilator that can achieve highly efficient ventilation. The new modification on the conventional wind turbine ventilator system may be achieved by adding a Savonius wind turbine above the conventional turbine to make it work more efficiently and help spinning faster. Three models of the Savonius wind turbine with 2, 3, and 4 blades' semicircular arcs are proposed to be placed above the conventional turbine of wind ventilator to build a hybrid ventilation turbine. A prototype of room model has been constructed and the hybrid turbine is placed on the head of the room roof. Performance's tests for the hybrid turbine with a different number of blades and different values o

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Publication Date
Thu Jun 01 2023
Journal Name
Baghdad Science Journal
Determination of essential and trace elements in various vegetables using ICP-MS
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Metal contents in vegetables are interesting because of issues related to food safety and ‎potential health risks. The availability of these metals in the human body ‎may perform many biochemical functions and some of them linked with various diseases at ‎high levels. The current study aimed to evaluate the concentration of various metals in ‎common local consumed vegetables using ICP-MS. The concentrations of metals in vegetables ‎of tarragon, Bay laurel, dill, Syrian mesquite, vine leaves, thymes, arugula, basil, common ‎purslane and parsley of this study were found to be in the range of, 76-778 for Al, 10-333 for B, 4-119 for ‎Ba, ‎2812‎-24645 for Ca, 0.1-0.32 for Co, 201-464 for Fe, 3661-46400 for K, 0.31–‎‎1.

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Publication Date
Sat Sep 21 2013
Journal Name
Nonlinear Dynamics
BER performance enhancement for secure wireless optical communication systems based on chaotic MIMO techniques
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Publication Date
Tue Jan 01 2019
Journal Name
Technologies And Materials For Renewable Energy, Environment And Sustainability: Tmrees19gr
Theoretical study for the calculation of some attenuation parameters of polymeric composites
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Publication Date
Fri Mar 31 2017
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Experimental Study for Commercial Fertilizer NPK (20:20:20+TE N: P: K) in Microalgae Cultivation at Different Aeration Periods
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Recently, microalgae have become a promising source in the production of biofuel. However, the cost of production is still the main obstacle to develop of this type of source. Although there are many extensive studies on the requirements provided for the cultivation of the microalgae, the study of the process, via the variables that affect the cultivation of microalgae, being still one of the important tasks to improve the production of biofuel. The present article is a serious attempt to investigate of use commercial fertilizer NPK (20:20:20+TE N: P: K) as considered a cheap nutrient medium in growth Chlorella vulgaris by comparison with traditional nutrient (Chu.10 medium). In addition, the current study addresses effect of di

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Publication Date
Thu Mar 16 2017
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Experimental Study for Commercial Fertilizer NPK (20:20:20+TE N: P: K) in Microalgae Cultivation at Different Aeration Periods
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Recently, microalgae have become a promising source in the production of biofuel. However, the cost of production is still the main obstacle to develop of this type of source. Although there are many extensive studies on the requirements provided for the cultivation of the microalgae, the study of the process, via the variables that affect the cultivation of microalgae, being still one of the important tasks to improve the production of biofuel. The present article is a serious attempt to investigate of use commercial fertilizer NPK (20:20:20+TE N: P: K) as considered a cheap nutrient medium in growth Chlorella vulgaris by comparison with traditional nutrient (Chu.10 medium). In addition, the current study addresses effect of different spar

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Publication Date
Wed May 10 2023
Journal Name
Journal Of Planner And Development
Relationship of LST, NDVI, and NDBI using Landsat-8 data in Duhok city in 2019-2022
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One of the most significant elements influencing weather, climate, and the environment is vegetation cover. Normalized Difference Vegetation Index (NDVI) and Normalized Difference Built-up Index (NDBI) over the years 2019–2022 were estimated based on four Landsat 8 TIRS’s images covering Duhok City. Using the radiative transfer model, the city's land surface temperature (LST) during the next four years was calculated. The aim of this study is to compute the temperature at the land's surface (LST) from the years 2019-2022 and understand the link, between LST, NDVI, and NDBI and the capability for mapping by LANDSAT-8 TIRS's. The findings revealed that the NDBI and the NDVI had the strongest correlation with the

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Publication Date
Wed Jun 10 2009
Journal Name
Iraqi Journal Of Laser
Characteristic of Discrete Raman Amplifier at Different Pump Configurations
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Discrete Raman amplifier have many attractive aspects over rare-earth doped fiber amplifier such as (EDFA) including arbitrary gain band, better adjustability of gain shape, and better linearity. This paper shows that discrete Raman amplifier has higher gain in bidirectional pumping than counter pumping. The gain increases with increasing fiber length, and the noise figure remain at the same value for short fiber length.

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Publication Date
Sun Sep 04 2016
Journal Name
Baghdad Science Journal
Study the Shielding Properties against Gamma-rays for Epoxy Resin Reinforced by Different materials
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In the present work the Buildup factor for gamma rays were studied in shields from epoxy reinforced by lead powder and by aluminum powder, for NaI(Tl) scintillation detector size ( ×? ), using two radioactive sources (Co-60 and Cs-137). The shields which are used (epoxy reinforced by lead powder with concentration (10-60)% and epoxy reinforced by aluminum powder with concentration (10-50)% by thick (6mm) and epoxy reinforced by lead powder with concentration (50%) with thick (2,4,6,8,10)mm. The experimental results show that: The linear absorption factor and Buildup factor increase with increase the concentration for the powders which used in reinforcement and high for aluminum powder than the lead powder and decrease with inc

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