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joe-2070
Evaluation of Convective Heat Transfer and Natural Circulation in an Evacuated Tube Solar Collector
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The evacuated tube solar collector ETC is studied intensively and extensively by experimental and
theoretical works, in order to investigate its performance and enhancement of heat transfer, for Baghdad climate
from April 2011 till the end of March 2012. Experimental work is carried out on a well instrumented collector
consists of 16 evacuated tubes of aspect ratio 38.6 and thermally insulated tank of volume 112L. The relation
between convective heat transfer and natural circulation inside the tube is estimated, collector efficiency, effect of
tube tilt angles, incidence angle modifier, The solar heating system is investigated under different loads pattern (i.e
closed and open flow) to evaluate the heat loss coefficient from tank and tubes, test the collector with various
aspect ratios (32.9 and 27.2). The enhancement in collector performance is studied by using two reflectors (Flat
Plate and Curved Plate) and nanofluid (Water-AL2O3).Theoretical work is run by software (Fluent 6.3), to compute
the velocity and temperature profiles within the tube, for different tube diameters, effect of tube junction angle and
stagnant region in the bottom of the evacuated tube. The experimental results shows that the heat loss coefficient
for tube is W/m2.K and for tank is W/m2.K, the maximum collector temperature is 79°C in winter and
99°C in summer, while that belong to nanofluid collector is 99°C in winter. The best tilted angle (optimum) of
evacuated tube is 41° annually. The collector efficiency increased when using nanofluid of (1, 0.6, 0.3)% volume
fraction as(28.4, 6.8, 0.6)% respectively. The efficiency decreases as (33, 62)% when decreasing tube aspect ratio
from 38.6% to 32.9% and 27.2% respectively. An increase of (16.9 and 7.08)% in collector efficiency is obtained
when using curved and flat plate reflectors respectively. From simulation the best junction angle of the tank is
22.5°. The stagnant region is influenced with changing heat flux, tilted angle and aspect ratio.

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Publication Date
Tue Oct 06 2020
Journal Name
College Of Islamic Sciences
Difficulties in learning and teaching Arabic to non-native speakers in the Kurdistan Region Types and solutions
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This research is a study of the difficulties of learning the Arabic language that faces Arabic language learners in the Kurdistan Region, by revealing its types and forms, which can be classified into two categories:

The first type has difficulties related to the educational system, the source of which is the Arabic language itself, the Arabic teacher or the learner studying the Arabic language or the educational curriculum, i.e. educational materials, or the educational process, i.e. the method used in teaching.

The second type: general difficulties related to the political aspect, the source of which is the policy of the Kurdistan Regional Government in marginalizing the Arabic language and replacing the forefront of th

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Publication Date
Wed Mar 30 2022
Journal Name
Journal Of Educational And Psychological Researches
Associations Between Phonological Processing and Working Memory in Students with and without Reading disabilities in Basic Education Cycle One Schools in Muscat
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The study aimed to examine the phonological processing profile for students with and without reading disabilities in cycle 1 schools of basic education in the Governorate of Muscat, Sultanate of Oman. The study participants included 306 students, 165 students with reading disabilities and 141 students without reading disabilities. The Comprehensive Test of Phonological Processing (CTOPP) and Working Memory Test (WMT) were administered to the participants. The results of the study showed that the mean score of students without reading disabilities was higher than that of students of reading disabilities in all measures of phonological processing, and that there are statistically significant differences on the  case of students in all

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Publication Date
Wed Dec 29 2021
Journal Name
Journal Of The College Of Education For Women
Professional Development and its Relationship with some Variables in the Light of Sullivan Theory among Male and Female Teachers in the Basic Education Schools in Sultanate of Oman: سالم بن ناصر بن سعيد الكحالي
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The study aims to reveal the level of professional development in basic education schools from the male and female teachers’ viewpoint in the Sultanate of Oman. It further aims to examine its relationship with some variables in light of Sullivan theory, and the differences in the level of professional development (teachers’ skills, professional participation, professional development problems) according to the gender variable, and the educational stage (first cycle/ second cycle). The study sample consisted of (93) teachers distributed as such: (46) male teachers, and (47) female teachers. A questionnaire was prepared and applied to measure the level of the professional development of the male and female teachers. The questionnaire c

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Publication Date
Sun Feb 25 2018
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
10.28936 PARTIAL PURIFICATION OF BACTERIOCIN PRODUCED FROM PEDIOCOCCUS ACIDILACTICI-FMAC278 AND WEISSELLA PARAMESENTEROIDES-DFR6 AND ITS APPLICATION IN THE PRESERVATION OF CHICKEN SAUSAGES: PARTIAL PURIFICATION OF BACTERIOCIN PRODUCED FROM PEDIOCOCCUS ACIDILACTICI-FMAC278 AND WEISSELLA PARAMESENTEROIDES-DFR6 AND ITS APPLICATION IN THE PRESERVATION OF CHICKEN SAUSAGES
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Bacteriocins were partially purified by ammonium sulphate 50% concentraction, bacteriocin activity of Pediococcus acidilactici-FMAC278 was 25600 U/ml with 5.8 folds and 7.6% yeild, the activity decrease to 12800 U/ml after dialysis with 6.3 folds and 3% yield, On the other hand the bacteriocin activity of Weissella paramesenteroides-DFR6 was 12800 U/ml with 2.7 folds and 8.8% yeild, after dialysis the activity became 6400 U/ml with 5.1 fold and 3.4% yield, Chicken Sausage were made by adding 0.25, 0.5 and 1% particaly purified bacteriocin to study its effect on microorganisms and increasing shelf life of Sausage. It is found that bacterial numbers were decreased after 3 days of storage at refrigerator at 0.5% conc. While the molds decrea

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Publication Date
Thu Dec 31 2020
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
DISPERSIVE LIQUID LIQUID MICRO EXTRACTION SPECTROPHOTOMETRIC DETERMINATION OF TELMESARTAN AND IRBESARTAN IN PHARMACEUTICALS SAMPLES: DISPERSIVE LIQUID LIQUID MICRO EXTRACTION SPECTROPHOTOMETRIC DETERMINATION OF TELMESARTAN AND IRBESARTAN IN PHARMACEUTICALS SAMPLES
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The current work is characterized by simplicity, accuracy and high sensitivity Dispersive liquid - Liquid Micro Extraction (DLLME). The method was developed to determine Telmesartan (TEL) and Irbesartan (IRB) in the standard and pharmaceutical composition. Telmesartan and Irbesartan are separated prior to treatment with Eriochrom black T as a reagent and formation ion pair reaction dye. The analytical results of DLLME method for linearity range (0.2- 6.0) mg /L for both drugs, molar absorptivity were (1.67 × 105-    5.6 × 105) L/ mole. cm, limit of detection were (0.0242and0.0238), Limit of quantification were (0.0821and0.0711), the Distribution coefficient were

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Publication Date
Wed Jun 03 2020
Journal Name
Political Sciences Journal
The Muslim Arab Self and the image of the other, religiously and culturally different: a critical analytical study of the causes and forms of political and social intolerance in Iraq
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This research aims to analyze the intellectual and civilizational regression that afflicted Iraqi and Arab society due to political and religious tyranny and internal conflicts, which was reflected in the deterioration of human rights values and the absence of equality and justice in dealing with the other religiously, which affected the reluctance of members of religious groups to interact with their national societies and then migrate to Outside, which contributed to a double loss, in terms of the loss of these societies by productive and effective national competencies, and in terms of distorting the image of Islam. The research stressed that the first treatments of this phenomenon are the consolidation of the values of citize

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Publication Date
Thu Dec 31 2020
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
ASTUDYON THERECORDOF EVALUATINGTHE SUPPLIERSACCORDING TO THE CONCEPT OF QUALITY AND BENEFITING FROM IT IN PRACTICE IN AL-FURAT STATE COMPANY AND FINDING POSSIBLE PROPOSALS FOR ITS DEVELOPMENT: ASTUDYON THERECORDOF EVALUATINGTHE SUPPLIERSACCORDING TO THE CONCEPT OF QUALITY AND BENEFITING FROM IT IN PRACTICE IN AL-FURAT STATE COMPANY AND FINDING POSSIBLE PROPOSALS FOR ITS DEVELOPMENT
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Success in selecting the best among the sources of supply is one of the most important factors in the efficiency of the procurement activity in the company, because the proper selection of the source of the supply significantly affect the achievement of what is desired by the factors of quality, quantity, price and service, and the ability of the competent supplier to meet everything associated with this Factors of commitments, hereby supporting the procurement function's efforts to fully discharge its responsibilities, and in view of adopting of Al-Furat company quality management system by applying the standards of ISO (9001: 2015) and purpose of getting the on-demand benefits from the application of international standards reg

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Publication Date
Sat Jun 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Future trends of the insurance sector in the integration of public insurance companies in Iraq And its impact on the quality of insurance service: Applied Study in the Iraqi General Insurance Company and the National Insurance Company
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     This study research to Showing The impact of the integration process on the quality of Insurance service and analyze the impact financially to determine whether there is any impact on the quality of the insurance service, in addition to identifying the obstacles that impede the merger between the insurance companies, insurance and the appropriate proposals for its' application and benefit from the benefits achieved.

The importance of The study lies in the fact that it is an important and vital spotlight that is becoming increasingly important in the world to confront the various difficulties and crises that have occurred  recently in light of the liberalization of international trade, globalization a

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Publication Date
Sun Feb 15 2026
Journal Name
Актуальные проблемы обучения русскому языку Xiii
ARABIC PHONO-GRAMMAR AND ITS RUSSIAN EQUIVALENTS AS A NEW APPROACH IN FL TEACHING (RUSSIAN AND ARABIC IN RUSSIAN AND ARABIC CLASSROOMS)
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Central and Eastern European Online Library - CEE journals, documents, articles, periodicals, books available online for download, Zeitschrfitendatenbank, Online Zeitschriften, Online Zeitschriftendatenbank

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Publication Date
Wed Oct 01 2008
Journal Name
Saudi Medical Journal
The therapeutic and prophylactic role of oral zinc sulfate in management of recurrent aphthous stomatitis (ras) in comparison with dapsone.
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KE Sharquie, RA Najim, RK Al-Hayani, AA Al-Nuaimy, DM Maroof, Saudi medical journal, 2008 - Cited by 74

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