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Thermal Characteristics of Closed Wet Cooling Tower Using Different Heat Exchanger Tubes Arrangement
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This paper presents thermal characteristics analysis of a modified Closed Wet Cooling Tower (CWCT) based on heat and mass transfer principles to improve the performance of this tower in Iraq. A prototype of CWCT optimized by added packing was designed, manufactured and tested for cooling capacity of 9 kW. Experiments are conducted to explore the effects of various operational and conformational parameters on the thermal performance. In the test section, spray water temperature and both dry bulb temperature and relative humidity of the air measured at intermediate points of the heat exchanger and packing. Heat exchangers consist of four rows and eight columns for an inline tubes arrangement and six rows and five columns for staggered tubes arrangement. According to experimental data, the inline tubes arrangement has a better thermal performance than the staggered tubes arrangement. The inline tubes arrangement enhanced thermal efficiency more than (7%) compared to the staggered tubes arrangement. Furthermore the effect of added packing to CWCT on thermal performance was significant compared to CWCT without packing. Comparing CWCT with packing, it has been observed that the best performance for the CWCT with packing under heat exchanger. It can be watched that the thermal efficiency for CWCT with packing under heat exchanger and CWCT with packing above heat exchanger approximately (28%) and (16%) higher than that CWCT without packing respectively. This study provides correlations to predict heat and mass transfer considering the influences of operational parameters for both inline and staggered heat exchanger tubes arrangement.

 

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Publication Date
Wed Oct 01 2014
Journal Name
Journal Of Economics And Administrative Sciences
Impact of investigator personality pattern on job stress at the General inspectors of offices /applied thesis
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This research studied the relationship of patterns of investigator personality with the big five dimensions (Extraversion, stability, interoperability, openness, and personal benevolent), in facing the job stress with its resources(characteristics of the role, quality of work, organizational structure, work environment, organizational policies, social relations, and organizational processes) which the investigators exposed to it at the General Inspectors Offices.

The researcher derived the idea of ​​research from the importance of the work of these offices in a confrontation of various cases of financial and administrative corruption in Iraq at the present time, since itis one of the most important in

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Publication Date
Fri Jan 01 2021
Journal Name
E3s Web Of Conferences 318, 03006 (2021)
Effect of External Post-Tensioning Strengthening Technique on Flexural Capacity of Simple Supported Composite Castellated Beam
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This research is carried out to study the effect of the external post-tensioning technique on the flexural capacity of simply supported composite castellated beam experimentally. In this research, seven composite castellated beams having the same dimensions and material properties were cast and tested up to failure by applied two concentrated loads at 700 mm from each end. Two external strands of 12.7 mm diameter were fixed at each side of the web of strengthening beams and located at depth 180 mm from top fiber of the section (dps) at each end of the beam. The strands have been tensioned by using a hydraulic jack with a constant stress of 100 MPa. This research aims to study the effect of the strengthening by different shapes of st

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Publication Date
Fri Sep 30 2022
Journal Name
Journal Of Economics And Administrative Sciences
The impact of digital leadership in the effectiveness of organizational crisis management by mediating strategic vigilance
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The current research aims to verify the impact of digital leadership as an independent variable, in the effectiveness of crisis management as a response  variable through centralizing strategic vigilance in the faculties of the University of Baghdad and its departments, and to investigate the level of interest of its leaders and subordinates in research variables, as well as coming up with recommendations that contribute to strengthening the practices of the three variables. In the university under study, and based on the researcher’s  interest  to diagnose the influence relationship between the variables, because of their importance in the university’s headquarters and its members on the one hand, and its refl

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Publication Date
Sun Jul 01 2012
Journal Name
Journal Of Educational And Psychological Researches
Psycological tolerance and its relationship to self-efficacy among the students of the University of Baghdad
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The study aimed to measure the phsycological tolerance and self-efficacy among the students of Baghdad university and knon the significant differences in psychological tolerance and self-efficacy according to the variables (Gender-Specialization)and the interaction between themas well as the study aimed to identify the strength and direction of the relationship between psychological tolerance and self-efficacy of the study sampleincluded asample of the current study(370) students from grades four ,the researcher used the measure of psychological tolerance and self-efficacy prepared by the researcher ,and the results showed that college students Generally have adegree of psychological tolerance and that there are statistically sig

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Publication Date
Thu Oct 01 2009
Journal Name
Iraqi Journal Of Physics
Crystal Growth of Semiconductor CuAl0.4Ti0.6Se2 and studding the Structural Properties of its Alloy and Thin Film
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Tetragonal compound CuAl0.4Ti0.6Se2 semiconductor has been prepared by
melting the elementary elements of high purity in evacuated quartz tube under low
pressure 10-2 mbar and temperature 1100 oC about 24 hr. Single crystal has been
growth from this compound using slowly cooled average between (1-2) C/hr , also
thin films have been prepared using thermal evaporation technique and vacuum 10-6
mbar at room temperature .The structural properties have been studied for the powder
of compound of CuAl0.4Ti0.6Se2u using X-ray diffraction (XRD) . The structure of the
compound showed chalcopyrite structure with unite cell of right tetragonal and
dimensions of a=11.1776 Ao ,c=5.5888 Ao .The structure of thin films showed

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Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Study of structural, optical and electrical properties of thin Ag2Cu2O4 films prepared by pulsed laser deposition
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The influence of sintering and annealing temperatures on the structural, surface morphology, and optical properties of Ag2Cu2O4 thin films which deposited on glass substrates by pulsed laser deposition method have been studied. Ag2Cu2O4 powders have polycrystalline structure, and the Ag2Cu2O4 phase was appear as low intensity peak at 35.57o which correspond the reflection from (110) plane. Scan electron microscopy images of Ag2Cu2O4 powder has been showed agglomerate of oxide particles with platelets shape. The structure of thin films has been improved with annealing temperature. Atomic Force micrographs of Ag2Cu2O4 films showed uniform, homogenous films and the shape of grains was almost spherical and larger grain size of 97.85 nm has o

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Publication Date
Sat Jan 12 2019
Journal Name
Journal Of The College Of Education For Women
Spatial analysis of mortality older population in the city of Baghdad , for the period (1997 - 2013)
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The current study is concerned with the analysis of spatial and temporal to death the elderly population in the city of Baghdad and at the level of administrative units Minor (districts and the areas) depending on the general population census of the province of Baghdad, data for 1997 and data from the Ministry of Health Department of Health and Vital Statistics for 2013.
The study showed differing age and quality of mortality rates at the level of administrative units of the study area, and notes the high mortality rates of elderly people of all age groups in 2013 compared to 1997, and this is due to security conditions after the USA occupation, and the accompanying conditions have affected the increase in mortality rates.

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Publication Date
Mon Mar 07 2016
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
Determination of mercury level in skin whitening creams: Determination of mercury level in skin whitening creams
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This study included the determination of mercury level in twelve samples of skin whitening cream available in local market in Baghdad by atomic absorption spectrophotometer ,all the samples analyzed was contained a detectable amount of mercury. The lowest concentration of mercury in the sample C (Top Shirley) was 0.482 μg/g, and the higher concentration was 29.54 μg/g in the sample J (Norseen) .It was also noted that the samples H (whitening speckle removing day cream) and K (whitening speckle removing night cream) did not mention in the label significance the name of the country of origin and date of the validity of the product.

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Publication Date
Sun Mar 18 2018
Journal Name
Mustansiria Dental Journal
The Effect of Pepsi Cola Beverage on Surface Roughness of Two Composite Resins (In Vitro study)
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An acidic environment causes surface changes of resin composites. Filler particlesize and filler distribution also have a direct effect on these surface changes. This invitro study evaluated the influence of Pepsi Cola drink on the surface roughness ofComposan LCM and Composan Ceram over time. Sixteen disc shaped specimens(10mm diameter, 2mm thickness) of each resin composite were fabricated, therebyforming two groups (n= 8). Surface roughness (Ra) was analyzed after 24 hrs beforeexposure to beverage. The specimens were submitted to a five minutes immersion inPepsi Cola three times daily interrupted by immersion in deionized distilled water (37C˚). Surface roughness measurements were done at 10, 30, and 60 days intervals. Datawere

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Publication Date
Wed Nov 01 2023
Journal Name
Journal Of Modern Project Management
THE IMPACT OF STRATEGIC INTELLIGENCE ON ORGANIZATIONAL PERFORMANCE: A TEXTILE SECTOR PERSPECTIVE OF A DEVELOPING ECONOMY
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In today’s competitive environment, organizational efficiency and sustained growth are crucial for survival. The performance of an organization is intricately connected to strategic planning, prompting firms to gather and leverage competitive information for a competitive advantage. Senior managers, recognizing this, initiate actions accordingly. This study aims to investigate the relationship between foresight, vision, strategic partnerships, motivation, system thinking, and organizational performance. Data, gathered through a self-administered questionnaire from various textile units, were analysed using structural equation modelling (SEM). The findings indicate that sub-constructs of strategic intelligence positively impact organizatio

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