Abstract

The study of oxygen mass transfer was conducted in a laboratory scale 5 liter stirred bioreactor equipped with one Rushton turbine impeller. The effects of superficial gas velocity, impeller speed, power input and liquid viscosity on the oxygen mass transfer were considered. Air/ water and air/CMC systems were used as a liquid media for this study. The concentration of CMC was ranging from 0.5 to 3 w/v. The experimental results show that volumetric oxygen mass transfer coefficient increases with the increase in the superficial gas velocity and impeller speed and decreases with increasing liquid viscosity. The experimental results of k_la were correlated with a mathematical correlation des

Receipt date:6/3/2021  acceptance date:4/5/2021 Publication date:31/31/2021

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The research in the role of variables contact for non-state actors have become more influential in the current of contemporary events, that related with the reality of seeking services and providing all of that in favor of maintaining the social peace, and ensuring its empowerment in order to make peace and stability outcomes as a real fa

Uncompleted Personality and it’s relation with Some Variables of the University Students

Abstract This study seeks to deal academically with how the EU treats clandestine immigration, through adopting a purley security approach, based on the European understanding of security threats posed to the security of communities and States in EU at all levels. So they agreed upon criminalizing this threat within the bloc while using repressive tools and steps to limit illegal immigrants flow to European territories. Accordingly, the EU gave the phenomen a security character. So it takes it from low politics level , that of employment and economic field to that of high politics, as a new security problem lying within a new security language embraced by ruling European elites, in other words EU touched on this issue as a speech act emp

The issue of volunteerism is one of the most important issues that have become prominent in social sciences and contemporary social thought, especially as a result of the transformations and changes that the world undergoes today. The voluntary sector has become the concern of all societies and governments for its development and service to society and various sectors. The practice of women is prominent in the work of volunteerism after 2003 in Iraq, but its work face a number of obstacles and hindrance. The problem of research is the obstacles of women's work in non-governmental organizations. The research aims to identify the nature and characteristics of volunteer work of Iraqi women.        &nb

أهمية البحث والحاجة إليه:

          من مظاهر التواصل الحضاري في جانبه العلمي والتكنولوجي هو متابعة أبناء مجتمعنا ولاسيما الشباب لكل منجز حديث واتخاذه وسيلة للحصول على المعلومات والمعرفة والتسلية، بحيث أصبح هذا التعامل ممارسة يومية حياتية، وهذا دليل على مدى تفتح ذهنية وعقلية ورغبات أبنائنا ومواكبتهم لروح العصر ومتطلباته وتعبيراً صادقاً عنه فضلاً عن إشغال أوقات ف

This study is about finding the estimation of tow equations, the comparative has been done between the estimations  by using seemingly unrelated regression equations for the variable and random error has been distribution with poisson and the variable and random error has been distribution with normal and the method by using oldenary lest square.

While in the application side, we have estimated the parameter of investment specification function for the sector of agriculture with the industry sector is enabled us to obtain an estimation efficiency for the model of seemingly unrelated Poisson regression equation.

المستخلص

The study seeks the relationship between the mathematical-procedural Knowledge and the logical-mathematical intelligence among students at the third stage in mathematics department. To this end, three questions were arisen: what is the level of mathematical-procedural Knowledge among the third stage students in mathematics department regarding their gender? Do male or female students have more logical-mathematical intelligence and are there significant differences base on their gender? What kind of correlation is between the level of mathematical-procedural Knowledge and the logical-mathematical intelligence of male and female students in the third stage in the mathematics department? A sample of (75) male and female students at the thir

Several problems have emerged as a result of urban expansion or the connection of urban areas with rural areas. This process has led to the urbanization of rural areas, and to have overlapping edges and margins of areas, which were outside the basic design of the city. Accordingly, the present research assumes that the accelerating growth of Baghdad population has contributed significantly to the process of unplanned urbanization. Thus, the study aims to examine the factors that have led to an increase of urban sprawl at the expense of the agricultural land. The study has thus adopted the descriptive, analytical, and historical approaches relying on the simple linear regression method to predict the phenomenon of urban expansion and its

Most of the studies conducted in the past decades focused on the effect of interest rates and exchange rates on domestic investment under the assumption that the independent variables have the same effect on the dependent variable, but there were limited studies that investigated the unequal effects of changes in interest rates and exchange rates, both positive and negative, on domestic investment.  This study used a nonlinear autoregressive distributed lag (NARDL) model to assess the unequal effects of the real interest rate and real exchange rate variables on domestic investment in Egypt for the period 1976 - 2020.  The results revealed that positive and negative shocks for both exchange rates have unequal effects on