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Estimation of Volumetric Mass Transfer Coefficient in Bioreactor
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This study is concentrated to investigate the effects of aeration and stirring speed on the volumetric mass transfer coefficient (KLa). A dynamic technique was used in estimating KLa values in order to achieve the aim of this study.

This study was done in 10L bioreactor by using two medias:-

  1. Dionized water
  2. Xanthan solution (1 g /L)

Moreover, the research covered a comparison between the obtained values of KLa.

The Xanthan solution was used because of its higher viscosity in comparison with water. It behaves similarly to the cultivation medium when organisms are cultivated in a bioreactor. Growth of organisms in the reactor leads to a change in the viscosity of the medium which affects the mass transfer.

Two variables, the effect of air flow rate (3-20 L/min) and the effect of stirring speed (250-700rpm) on KLa value were studied. Other parameters such as temperature, liquid volume, and stirrer shape and stirrer position were held constant; the results demonstrated an increase in KLa – value and mass transfer with increasing stirrer speed. Thus at higher speed, better dispersion of the bubbles was obtained. Therefore, that increased the surface / volume ratio which increased the mass transfer area i.e. KLa value.

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Publication Date
Thu Jun 23 2022
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Phytochemical screening and Free radicals scavenging activity of leaves of Echinops polyceras Boiss. grown in Syria
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Free radicals are reactive compounds, their excessive production is considered to be an important cause of oxidative damage in biomolecules causing degenerative diseases. Polyphenols are one of the most important groups of secondary metabolites of plants, which have an antioxidant activity depending on their properties as hydrogen donors. Echinops polyceras Boiss. (Asteraceae) is one of Echinops genus species that spread in Syria, Lebanon, and Palestine. Phytochemicals found in this species leaves have been extracted with gradient polarity solvents, and primary screening of the secondary metabolites was established. The phenolic compounds and flavonoids contents were determined. The free radicals scavenging activity was evaluated for all

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Scopus Crossref
Publication Date
Thu Mar 30 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Evaluation of the Role of Interleukein-2 and Interleukein-4 in the Immunopathogenesis of Steroid Therapy Resistance in Iraqi Asthmatic Patients
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Interleukins (IL-2 and IL-4) are increased in asthmatics and were reported to induce resistance to steroid therapy in some patients who fail to get benefit from glucocorticoids when used in full dose and for long period of time. In this context, the present study was conducted on Iraqi patients to provide additional laboratory mean, beside the clinical diagnosis, for the decision whether the asthma is steroid sensitive or resistant by monitoring the level of immunoglobulins, complement proteins and interleukins among asthmatic patients (steroid sensitive or resistant) and the possible contribution of other factors like age, sex and environments in the development of steroid resistance. A total number of 55 asthmatics and 28 normal subjec

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Crossref
Publication Date
Sat Jan 01 2022
Journal Name
Revista Iberoamericana De Psicologia Del Ejercicio Y El Deportethis Link Is Disabled.,
THE EFFECT OF EXERCISES WITHIN A FACTORY HIERARCHICAL STRUCTURE IN REDUCING THE DEGREE OF PAIN IN A SAMPLE OF BACK PATIENTS
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Scopus
Publication Date
Mon Feb 18 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The Role of the financial Statements in Achieving of the Banking Supervision: An Applied Study in A sample of Iraqi Banks
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Banks are considered the main basis of financial sector ,so they must be submitted to sound and strict regulatory system and so as to ensure their operations and according to instructions and regulations , in order to maintain the integrity of the banking sector and financial sector in general .One of the importance regulatory tools that are adopted by the Iraqi Central Bank to control over the banks an financial and periodic statements that are provided by the banks in accordance with planned schedules .The financial statements of the banks must reflect clearly and accurately financial situation and the result of their activities during the period in which they represent to achiveing its purposes.So it has the goal of Search is statemen

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Crossref
Publication Date
Tue Mar 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
The role of strategic leadership in knowledge management processes "Diagnostic Study in the Office of the Ministry of Oil - Project Department"
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The research deals with the important and modern two subjects, strategic leadership which have six demotions and knowledge management
(four demotions') . the gools & the research is to know the relation & the effect them in the oil ministry (project department) , the sample was (50) persons who works in the department the questionnaire was the tool of data gathering .

The research divided to four parties, the first  to the theotical review of the research variables, the second to the research methrology, the third to analysis and discoed the empirical results the last to the conclusions and recommendations .

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Crossref (1)
Crossref
Publication Date
Thu Jun 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
The Impact of Architecture design quality in build competitiveness for contracting companies in The Ministry of Housing and Construction of Iraq
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The study aimed at interpreting the role of architectural design quality in in build competitiveness model in accordance with the proposal included the idea of ​​architectural design quality for its removal; interesting design factors of the environment, good design of the spaces, and design aesthetic explanatory variable. The competitiveness dimensions; the level of innovation, stimulate research, and the quality of the company's products, and activating the role of human resources, entrepreneurship, profitability, market share and competitiveness, variable responsive. The study of construction companies in the Ministry of Housing and Construction has taken the Iraqi society for the study. The sample consisted of (48) manage

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Crossref
Publication Date
Thu Apr 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
The Role of the values of accounting culture in maximizing financial performance - A field study in a sample of Iraqi banks
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The influence of culture on accounting systems and practices, including financial reports and accounting information through the values ​​identified by Gray and derived from social-cultural values, and the four accounting values ​​were derived from generally accepted accounting principles represented by (Conservatism, Uniformity, Secrecy, and Professionalism). Important and significant in maximizing financial performance, and measuring the extent of the role of these values ​​in improving financial performance through attention to the values ​​of accounting culture, this research

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Crossref
Publication Date
Thu Jun 30 2022
Journal Name
Sports Culture
Analysis of the kinetic path of some physical measurements and kinetic abilities in terms of the direct attack in the foil
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Through the researchers' acquaintance with the previous studies, the problem was identified as that the preparation of training curricula in all its units must be based on accurate scientific foundations. Positively affect the type of attack and its implication in the presence of correlational relations, whether direct or indirect, i.e., precedence in training and in preparing units Therefore, the researcher decided to build a causal model to know the relationships to show the best model of the direct straight attack. The study aimed to build a causal model for the most important physical measurements and kinetic capabilities of the direct straight attack in the research sample. The two researchers used the descriptive approach in t

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Crossref (6)
Crossref
Publication Date
Mon Apr 01 2019
Journal Name
Journal Of Educational And Psychological Researches
The Role of Tabuk University in Intellectual Education for Students in the Light of the Requirements of Enhancing the Intellectual Security
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The study aims to identify the degree of Tabuk University practices to raise the intellectual awareness of students through scientific research, as well as to identify the degree of Tabuk University practicing to raise the intellectual awareness through the educational process (faculty member – activities). The study also seeks to identify the degree of Tabuk University practicing to raise the intellectual awareness of students through community service and university media. The study is descriptive in nature that employed the questionnaire as a tool in collecting data. Total of (540) students were chosen randomly from different colleges at universities of Tabuk to form the study sample. The results showed that faculty member has pract

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Publication Date
Sun Aug 10 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Concentrations of selected elements in permanent teeth and enamel among a group of adolescent girls in relation to severity of caries
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Background: Human teeth considered to be an important etiological host factor in relation to dental caries through its morphology and composition. Elements may incorporate in tooth structure during pre and post-eruptive period changing the resistance for caries. The aims of this study were to determine the concentration of selected major (Calcium and phosphorus) and trace elements (Ferrous iron, nickel, chromium and aluminum) in permanent teeth and enamel among a group of adolescent girls in relation to severity of dental caries Material and Methods: The study group consisted of 25 girls with an age of 13-15 years old referred by Orthodontists for extractions of upper first premolars (two sides). Tooth and enamel samples were prepared for

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