Preferred Language
Articles
/
alkej-140
Estimation of Volumetric Mass Transfer Coefficient in Bioreactor
...Show More Authors

 

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.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Oct 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
The applicability of green productivity tools: An analytical study in a sample of industrial companies in the province of Nineveh
...Show More Authors

                The current research aims to identify the most important green productivity tools GPT and the possibility of applied in industrial companies in general and the companies operating in the province of Nineveh, in particular, as well as the study of some personality characteristics and functional, which is believed to be an impact on the application of these tools in industrial companies. Accordingly, the research community of managers in the company of medicines and medical supplies ready-made clothes _ operating in the province of Nineveh, who are (80) while the manager was subjected to research procedures (49) Director representing (61.25%)

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Aug 02 2025
Journal Name
Al–bahith Al–a'alami
Effectiveness of Dialogic Communication in Online Public Relations with an Audience : (Analytical Study of the Websites of Universities in UAE)
...Show More Authors

The Study addressed the effectiveness of dialogic communication in online public relations with an audience of higher education institutions in the United Arab Emirates. The study aimed to know about the interest extent of higher education institutions through their websites with the elements of dialogic communication in online public relations to communicate with their audience. The researcher used survey methodology and content Analysis tool as an essential tool for collecting information. Some of the important results of the study are: The websites of higher education institutions in terms of indicators of ease of use; the main links on the websites are clearly available on the opening page, there is a map on the websites, reduce depe

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Feb 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
The role of accounting responsibility in the success of the reform of financial and administrative / applied research in high School
...Show More Authors

The reform process is a dynamic process going on, especially the administrative and financial reform, which contributes to the work and directing operations towards success and continuous development, which requires determining the validity and the responsibility and the rights and duties of all officials in the school settings (within the formations educational institutions) for the purpose of reducing the administrative and financial corruption, and then ensure management efficient and effective way by taking advantage of the physical, financial and human resources available to achieve the greatest benefit at the lowest cost to the fact that the follow-up performance on an ongoing basis in accordance with the specific of powers

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Mar 07 2010
Journal Name
Baghdad Science Journal
Effect of magnetic water in the some parameters of growth & activity of some enzymes in the ( Raphanus raphanistrum L.) Plant
...Show More Authors

View Publication Preview PDF
Crossref
Publication Date
Sat Aug 02 2025
Journal Name
Journal Of Baghdad College Of Dentistry
In vivo histological evaluation of the effect of the topical application of estrogen hormone on wounds healing in ovariectomized rabbit
...Show More Authors

Background: Wound healing, as a normal biological process in the human body, is achieved through four precisely and highly programmed phases: hemostasis, inflammation, proliferation, and remodeling. Growth factors released in the traumatized area promote cell migration into the wound area (chemotaxis), stimulate the growth of epithelial cells and fibroblasts (mitogenesis), initiate the formulation of new blood vessels (angiogenesis), and stimulate matrix formation and remodeling of the affected region. One of factors that effects on wound healing is a sex hormones and one of these hormones is an estrogen hormone. A wide range of cutaneous cell types (eg, fibroblast, endothelial, epithelial, and inflammatory) expressed estrogen receptors, in

... Show More
View Publication Preview PDF
Publication Date
Wed Oct 05 2016
Journal Name
Al-academy
The Employment of Brainstorming in developing the idea of design of Fine Arts Institute Students in Designing the Technical Advertisement
...Show More Authors

Brainstorming is considered as one of the manners that develop learners' mental abilities. Besides, it can help learners get a lot of ideas and thoughts. And by following applied steps to answer the problem concerned, the researcher carried out this practical study aimed at:Developing the ideas of design of third year students/Institute of Fine Arts/Evening Studies- Baghdad/First Rusafa by employing Brainstorming mechanism to develop the ideas of design of institute students in designing the technical advertisement and to achieve the authenticity of the goal of the research, Department of Plastic Arts/Institute of Fine Arts/Evening Studies/Baghdad-First Rusafa was chosen as a case study for the research. It embraced (20) students who rep

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Jun 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
The impact of corporate governance in the promotion of business ethics A prospective study in a sample of private banks
...Show More Authors

 The study aims to know the role of governance in the consolidation of the principles of business ethics, through the application of the principles of governance and the dimensions of business ethics in the private sector. And knowledge of the validity of the hypothesis key of the current study according to which "increases the ethics of business organizations strength and coherence in the presence of the principles of governance" as it was distributed the questionnaire to a sample of a chairman and board members and managers department  and heads of sections in some of the private banks. I have been using correlation analysis and regression testing (t) to see the moral differences and to find out the c

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Sep 15 2023
Journal Name
Al-academy
The aesthetics of abstract expressionism and its representations in the artistic productions of the students of the Department of Art Education
...Show More Authors

The research section tagged (Aesthetics of Abstract Expressionism and its Representations in the Artistic Products of Students of the Department of Art Education) into four chapters and it included in..
The first chapter: (the methodological framework) for the research, and the research problem is summarized through the question (what are the aesthetics of abstract expressionism and its representations in the artistic productions of the students of the Department of Art Education). In the products of students of the Department of Art Education).
The aim of the research was (discovering the aesthetics of abstract expressionism and its representations in the artistic products of the students of the Department of Art Education). As we

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Jan 02 2017
Journal Name
Journal Of Educational And Psychological Researches
The effectiveness of the structural model of learning in the acquisition of geographical concepts among students of the first grade average)
...Show More Authors

The current research aims to find out ( the effectiveness of the structural model of learning in the acquisition of geographical concepts at the first grade average students ) , and achieving the goals of research has been formulating the null hypothesis of the following :

    " There is no difference statistically significant when Mistoi (0.5 ) between the mean scores of the collection of students in the experimental group that is studying the general geographical principles " Bonmozj constructivist learning " and the mean scores of the control group , which is considering the same article ," the traditional way " to acquire concepts.

The researcher adopted th

... Show More
View Publication Preview PDF
Publication Date
Sun Oct 02 2011
Journal Name
Journal Of Educational And Psychological Researches
Levels of Geometrical Thinking of The Students of Mathematic Department in Basic Education College at AL- Mustansiriyah University
...Show More Authors

This  research aimes to expose the levels of geometrical thinking among the students of mathematic department in Basic Education College at AL-Mustansiriyah University throughout their respondes on the test of  geometrical thinking which consists (50) multi- choice items  distributed on the first four levels of Van Hiele ( recognition – analysis – ordering – deduction ).

The validity and the reliability of the test have been investigated. Besides, the difficulty and its discrimination have been measured. The activity of the wrong variables has been measured.

The test has been applied on (180) male and female students of the first, second and third grades.

... Show More
View Publication Preview PDF