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Hydrodynamics, Mass and Heat Transfer in Reactive Distillation
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      The ethyl acetate synthesis via heterogeneous reactive distillation is studied experimentally using ethanol and acetic acid. Three types of cation exchanging resins were used as catalysts: Zerolit 225, Zerolit 226 and Ambylite 400. Experiments were carried out in two units of the same dimensions. Each unit consisted of three sections: rectifying, reactive and stripping sections of heights (60+25+20) cm respectively and 2.5cm column diameter. The first unit (column-A-) was a fractionation type and the second unit (column-B-) was packed column. The packing type was hollow glass cylinders with 10 mm height, and 4, 5 mm inner and outer diameter respectively.

      The experiments were carried out by using two operation modes. The semi-batch and continuous operation mode. In the first part of present investigation, the semi-batch mode was used to evaluate the catalyst type and to evaluate the performance of reactive distillation unit configuration (Fractionation and packed column). Results show that, the column-B- gave higher conversion rates than column-A-. This is attributed to the high surface area available for liquid vapour contact in packed type column, which leads to increasing mass transfer rates.  On the other hand, Ambylite 400 catalyst showed higher activity for esterification reaction than other two types of catalysts.

      The second part of work continued with column -B- only. It is well known that, the esterification process is regarded one of exothermic reactions. Therefore, the monitoring of the temperature distribution along column axial for all three types of catalysts showed that the temperature distribution was essentially the same due to steady state operation in continuous operation mode. On the other hand, the effect of reflux ratio on temperature distribution was clearly noted, that is as the reflux ratio increased the temperature distribution along the column was reduced for each type of catalysts.

      On the other hand, the experimental results point that, as a reflux ratio increases the conversion rates of acetic acid is increased too because such increasing is related to high mass transfer rates between  vapour and liquid along reactive distillation column.

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Publication Date
Sat Jan 01 2022
Journal Name
International Journal Of Research In Social Sciences & Humanities
knowledge sharing and its role in Organizational excellence
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The current research aims to diagnose the extent of interest in knowledge sharing and its role in achieving organizational excellence at the level of the Iraqi environment Primary data through descriptive statistics (arithmetic mean, standard deviation, coefficient of variation, percentages, frequencies) and hypothesis testing using appropriate statistical methods for inferential statistical analysis (Pearson correlation coefficient, simple linear regression, multiple regression, path analysis) and checking the quality of the data from During (normal distribution, confirmatory factor analysis, structural modeling method, and exploratory factor analysis), after collecting data from (358) observations from the company’s leaders, as

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Publication Date
Thu Jun 18 2020
Journal Name
Rimak International Journal Of Humanities And Social Sciences
STRESS IN ENGLISH AND ARABIC: A CONTRASTIVE STUDY
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DBN Rashid, Rimak International Journal of Humanities and Social Sciences, 2020

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Publication Date
Mon Apr 03 2023
Journal Name
The Journal Of Physical Chemistry A
Excited-State Aromaticity Reversals in Naphthalene and Anthracene
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Aromaticity reversals between the electronic ground (S0) and low-lying singlet (S1, S2) and triplet (T1, T2, T3) states of naphthalene and anthracene are investigated by calculating the respective off-nucleus isotropic magnetic shielding distributions using complete-active-space self-consistent field (CASSCF) wavefunctions involving gauge-including atomic orbitals (GIAOs). The shielding distributions around the aromatic S0, antiaromatic S1 (1Lb), and aromatic S2 (1La) states in naphthalene are found to resemble the outcomes of fusing together the respective S0, S1, and S2 shielding distributions of two benzene rings. In anthracene, 1La is lower in energy than 1Lb, and as a result, the S1 state becomes aromatic, and the S2 state becomes anti

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Publication Date
Tue Jan 01 2019
Journal Name
World Journal Of Dentistry
Facial Fractures in Preschool- and School-aged Children
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Aim: The purpose of this study was to analyze the patterns of facial fractures in children and to compare them between preschool- and school-aged children. Materials and methods: This retrospective observational study included 57 children with facial fractures. The variables analyzed were the age of the patients—divided into a preschool-aged group (0–5 years) and a school-aged group (6–12 years)—gender, cause of trauma, the facial bones involved, the pattern of fracture, the modality of treatment used, the time between injury and treatment, and the postoperative complications. Results: The incidence of facial fractures in children ≤12 years was 30.2%. The patients consisted of 40 (70.2%) males and 17 (29.8%) females, and most pati

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Publication Date
Thu Jun 02 2011
Journal Name
Вестник Воронежского государственного университета. Серия: Лингвистика и межкультурная коммуникация
direct and indirect nomination in single-component characteristics...
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Publication Date
Sat Oct 01 2016
Journal Name
Journal Of Engineering
Intelligence in Construction between Contemporary and Traditional Architecture
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The authentic traditional architecture proved that it is very convenient to the environmental and social regulations where it appeared and lasted for hundred of years.

This traditional architecture got the intelligence in providing thermal comfort for their occupants by the intelligent usage of the building materials and the intelligent planning and designs which took in consideration the climatic condition and the aerodynamics of the whole city as one ecological system starting from the cold breeze passing through its narrow streets till it enters the dwelling units and glides out through the wind catchers.

This architecture had been neglected and replaced by modern imported architecture which had collap

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Publication Date
Mon Mar 27 2023
Journal Name
Recent Progress In Science And Technology
Recent Progress in Science and Technology Vol. 8
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Publication Date
Sun Jan 01 2012
Journal Name
Biochemistry Research International
Endocytosis and Sphingolipid Scavenging in Leishmania mexicana Amastigotes
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Leishmaniaspecies are the causative agents of the leishmaniases, a spectrum of neglected tropical diseases. Amastigote stage parasites exist within macrophages and scavenge host factors for survival, for example,Leishmaniaspecies utilise host sphingolipid for synthesis of complex sphingolipid. In this studyL. mexicanaendocytosis was shown to be significantly upregulated in amastigotes, indicating that sphingolipid scavenging may be enhanced. However, inhibition of host sphingolipid biosynthesis had no significant effect on amastigote proliferation within a macrophage cell line. In addition, infection itself did not directly influence host biosynthesis.

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Publication Date
Sun Feb 08 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Periodontal health status and salivary parameters in pregnancy
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Background: Pregnancy is considered a major risk factor for development and progression of periodontal disease. There are hormonal changes in both estrogen and progesterone hormones in addition to bacterial effect and poor oral hygiene that will enhance development of periodontal disease in pregnant women. Materials and methods: Seventy subjects were enrolled in the study, the subjects with an age range (20-35) years old without any history of systemic disease. The subjects were divided into 20 non-pregnant women they represent the control group (G I), 30 pregnant women with gingivitis (GII) and 20 pregnant women with periodontitis (GIII).All periodontal parameters (plaque index, gingival index, bleeding on probing, probing pocket depth an

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Publication Date
Wed Jan 30 2013
Journal Name
Al-kindy College Medical Journal
Multiple Hydatid Cysts in Lungs, Liver and Spleen
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We presented here a 25years old lady with a multiple hatdtid cysts in lung and liver and spleen in large number in each organ. Which regarded inoperable and difficult to treared.We use medical treatment with antihelimenthes drugs in new regime and follow-up over 1year clinically, laboratory investigations, U/s and CT.scan. There was good disappearance of liver and spleen cysts with very good response in lungs.

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