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joe-2109
Experimental Study of Power Increase Transient in Heat Generation Systems Simulated By Immersed Heat Source
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Theoretical and experimental investigations of the transient heat transfer parameters of constant heat flux source subjected to water flowing in the downward direction in closed channel are conducted. The power increase transient is ensured by step change increase in the heat source power. The theoretical investigation involved a mathematical modeling for axially symmetric, simultaneously developing laminar water flow in a vertical annulus. The mathematical model is based on one dimensional downward flow. The boundary conditions of the studied case are based on adiabatic outer wall, while the inner wall is subjected to a constant heat flux. The heat & mass balance equation derived for specified element of bulk water within the annulus and solved by using Laplace method to
determine the variation of bulk water temperature. The experimental investigation included a set of experiments carried out to investigate the temperature variation along the heat source for power increase transient of (5%, 10%, 15% and 20%) of its nominal value during and after reaching the steady state condition. Estimation of the boiling safety factor is predicted and compared with the theoretical values. Reliable agreement between experimental and theoretical approaches is reached. The later showed that the elapsed time required for the clad surface temperature to reach its steady state values after each transient is less than that related to bulk water temperature. New correlation for prediction of critical heat flux, CHF based on inlet water temperature and water mass flux are investigated and compared with CHF correlations obtained from previous researches. Specific recommendations concerned with preventive measured required to eliminate the effect of boiling crisis are concluded based on theoretical and experimental results related to transients setting times obtained from each case study.

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Publication Date
Wed Sep 20 2006
Journal Name
00
INVESTIGATING SOME OF THE SYNTACTIC ERRORS MADE BY EFL COLLEGE STUDENTS IN WRITTEN ENGLISH EXPRESSIONS استقصاء بعض الاخطاء النحوية لطلبة الكلية دارسي اللغة الانكليزية لغة اجنبية في التعابير الانشائية
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Publication Date
Sun Mar 06 2011
Journal Name
Baghdad Science Journal
Isolation and Identification of Vibrio cholerae causes Epidemic cholera 2007 in Iraq by Rapid Method (Immunochromatographic one step rapid visual test) and comparing it with the traditional Bacterlogical Methods
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This study was for searching for Cholera Bacteria serotype which causes epidemiology Cholera in the 2007 in a fast method which contains (Rapid Visual Test) (Crystal V.C.) which was used for the first time in Iraq to diagnosis of Cholera Bacteria & compared with the traditional bacteriology method. The Cholera disease is one of the most dangerous epidemiological diseases which lead to death with a percentage of (50 – 70) % in the severe cases for untreated patients . For this purpose, 100 samples of stool from the patients from a (13) hospitals in Baghdad Governorate in the period from August to the end of December. The Cholera was diagnosis in two methods, 1st method was the fast method using the nitrocellulose which is coated with anti-

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Publication Date
Thu Mar 30 2023
Journal Name
Journal Of Economics And Administrative Sciences
The Role of Electronic Customer Trust Building Tools On Excellent Performance An analytical study of the opinions of a sample of individuals in the administrative and leadership positions in the Northern Cement Company
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The current study aims to overcome the conflicts facing the company in its way of staying and continuing to maintain its performance excellent in light of the intense competition, which made it seek to find strong ways and links with its customers through electronic communication using electronic platforms, and this put confidence and safety in The place of suspicion and fear of not fulfilling credibility or violating the privacy, so this research comes to answer about the question:  “Can the company achieve an excellent performance by relying on the customer's electronic confidence?”.

The study followed the descriptive and analytical approaches by providing a virtual model and testing the zero hypotheses, which stipulat

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Publication Date
Sun Mar 01 2015
Journal Name
Baghdad Science Journal
Synthesis of Mixed Ligand Complexes of M(II) Dithiocarbamato Derivative and 2,2'-bipyridyl and Study their Cytotoxic Effect Against HepG2 Cell Line in vitro
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Mixed ligand of Co and Ni (II) complexes were prepared from [5-(p-nitrophenyl)-4/-phenyl-1,2,4-triazole-3-dithiocarbamato hydrazide](TRZ.DTC) as primary ligand and 2,2'-bipyridyl (bipy) as a co-ligand with metal salts. These complexes were analytically and spectroscopically characterized in solid state by elemental analyses, flame atomic absorption, magnetic susceptibility and molar conductance measurements, as well as by UV–Vis and FTIR spectroscopy. Infrared, ultra violet spectra reveal a bidentate coordination of the two ligands with metal ions 1:1:1 mole ratio. Room temperature magnetic moments and solid reflectance spectra data indicate paramagnetic complexes with five-coordinate square pyramidal geometry for nickel (II) comple

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Publication Date
Fri Jan 01 2010
Journal Name
Iraqi Journal Of Science
IMMUNONOLOGICAL EVALUATION AND ACUTE TOXICITY STUDY WITH FERTILITY EXAMINATION FOR THE EFFECT OF AQUEOUS EXTRACT FROM DRIED FRUITS OF Piper nigrum L. IN MICE
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The research work was conducted to investigate the effect of oral administration of water extract of black pepper at doses of (1, 5) mg/kg body weight for two weeks daily by determining the genotoxic effect (mitotic index), evaluation of immunological effect (IgG, IgM, IgA, C3, C4) and measuring fertility hormones (follicles stimulation hormone/FSH, lutenising hormone/LH) levels with histopathological examinations of female albino swiss mice ovaries in comparison with control (normal saline). A clear effect in increasing mitotic activity was reveled for both doses in comparison with control. Results also showed a significant increase in the value of the all immunological parameters at both doses in comparison with control. Also obvious rais

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Publication Date
Sat Feb 28 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Aging effect of different types of composite resin restoration on shear bond strength to different orthodontic adhesives with sapphire bracket (In vitro comparative study)
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Background: This study was performed to determine the effect of aging of different types of composite material restorations on: Shear bond strength (SBS) to light cure and no mix chemical cure orthodontic adhesives with sapphire bracket and the debonding failure sites. Materials and methods: One hundred forty four composite disks were made from three different composite resin materials which are: 3M Filtek Z250, 3M filtek Z350 and 3M Valux plus, each group with (48) disks each, then according to the duration of storage each group was subdivided into two equal groups one of them stored for one day and the other was stored for one month, then each group was further subdivided into two equal subgroups with (12) disks each one bonded with ligh

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Publication Date
Sat Jun 15 2019
Journal Name
Journal Of Baghdad College Of Dentistry
Investigation of the consistency between reported chief complaint and periodontal health status of Iraqi patients in relation to age and gender (A retrospective study)
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Publication Date
Wed May 01 2013
Journal Name
Chemical And Process Engineering Research
Synthesis and Characterization of Polycyclicacetal Derived from PEG & Erythro-Ascorbic Acid Derivative and Study Its Effect on the Activity of ACh Enzyme (In Vitro)
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Polycyclicacetal was prepared from the reaction of PEG with aldehyde derived from Erythro-ascorbic acid (pentulosono-ɣ-lactone-2,3-enedianisoate).All these compounds were characterized by Thin Layer Chromatography (TLC) and FTIR spectra and aldehyde was also characterized by (U.V-Vis), 1HNMR, 13CNMR, and mass spectra.The inhibitory effect of prepared polymer on the activity of human serum AcetylCholinesterase has been studied in vitro. The polymer showed a remarkable activity at low concentration (4.7x10-3 – 4.7x10-8M).

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Publication Date
Sat Jun 15 2019
Journal Name
Journal Of Baghdad College Of Dentistry
Investigation of the consistency between reported chief complaint and periodontal health status of Iraqi patients in relation to age and gender (A retrospective study)
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Background: Chief complaint of patients attending dental clinic represents the first step towards treatment plan. However, most of patients are not aware but the extent and severity of periodontal disease, which could be also, misdiagnose by the dentist. Aim of the study: To investigate whether reported chief complaint(s) are consistent with oral hygiene status Materials and methods: Records of 1102 patients, attending periodontics clinics in the college of dentistry/ university of Baghdad, were used to determine ten most commonly reported chief complaints. Sample of patients was further subdivided according to gender and age. In addition, plaque and gingival index were recorded to determine oral hygiene status. Results: Patients mostly

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Publication Date
Sun Sep 02 2012
Journal Name
Baghdad Science Journal
Study The Predation Efficiency of Chrysoperla carnea (Stephens)(Neuroptera :Chrysopidae) Larvae in Controlling Nymphs and Adults of Cabbage Aphid Brevicoryne brassicae (L.) (Homoptera :Aphididae).
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Results showed high efficiency of the predator Chrysoperla carnea (Stephens) to attack and consume nymphal instars and adults of cabbage aphid, Brevicoryne brassicae (L.).The total average of the nymphal instars consumed by the larval stage of predator were 308.67, 285.9, 198.77, 154.7 for 1st ,2nd ,3rd ,4th nymphal instars respectively .While it was 110,107.9 for apterae and alatae respectively . Also, predation efficiency increases with the progress of the larval instars up to the third (last) which was the most voracious .The 1st instar nymph consumed by the larvae of the predator were 47,80,181.67 nymphs ,with predation rate of 14.71% , 23.75% and 50.13% for 1st ,2nd and 3rd larval instars

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