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

Abstract

                The aim of the research is to demonstrate the impact of long-term investment on profitability, and in order to achieve this goal, long-term investment was chosen, represented by (the ratio of long-term investments to total investments, the ratio of long-term investment to the total (deposits) as independent variables, and studying its impact on the dependent variable, which is profitability as measured by the rate of return on investments, the rate of return on equity. In order to reach the results, the inductive approach and the analytical descriptive approach were used, and the research found a significant impac

The research aims to enhance the level of evaluation of the performance of banking transactions control policies and procedures. The research is based on the following hypothesis: efficient transactions control policies and procedures contribute enhancing financial reporting, by assessing non-application gap of those policies and procedures in a manner that helps to prevent, discover, and correct material misstatements. The researchers designed an examination list that includes the control policies and procedures related to the transactions, as a guide to the bank audit program prepared by the Federal Financial Supervision Bureau. The research methodology is

Plant regeneration and cormel production was carried out from callus cultures initiated from White Prosperity and Priscilla Gladiolus Varities. It is aimed to produce plants and cormels in vitro all year round. The study included many experiments, these were the effect of Naphthalene acetic acid (NAA) and Kinetin (Kin) interaction on callus initiation, effect of Benzyl adenine (BA) on shoot regeneration from callus culture, effect of NAA on rooting after 30, 40 and 50 days in culture. The role of the type of agricultural medium (Peat moss or river sand and their mixture on plantlets survival after weaning was studied. Results showed that the interaction between NAA and Kin induced callus on axillary bud explants. Callus was best ini

Nasryia oil field is located about 38 Km to the north-west of Nasryia city. The field was discovered in 1975 after doing seismic by Iraqi national oil company. Mishrif formation is a carbonate rock (Limestone and Dolomite) and its thickness reach to 170m. The main reservoir is the lower Mishrif (MB) layer which has medium permeability (3.5-100) md and good porosity (10-25) %. Form well logging interpretation, it has been confirmed the rock type of Mishrif formation as carbonate rock. A ten meter shale layer is separating the MA from MB layer. Environmental corrections had been applied on well logs to use the corrected one in the analysis. The combination of Neutron-Density porosity has been chosen for interpretation as it is c

Understanding, promoting, and teaching media literacy is an important societal challenge. STEM educators are increasingly looking to incorporate 21st century skills such as media literacy into core subject education. In this paper we investigate how undergraduate Computer Science (CS) students can learn media literacy as a by-product of collaborative video tutorial production. The paper presents a study of 34 third-year CS undergraduates who, as part of their learning, were each asked to produce three video tutorials on Raspberry Pi programming, using a collaborative video production tool for mobile phones (Bootlegger). We provide results of both quantitative and qualitative analysis of the production process and resulting video tutorials,