Evaluation of Tensile Strength and Durability of Microbial Cement Mortar
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The current research aims to diagnose the nature of the relation between dynamic capabilities as an independent variable and competitive advantage as a respondent variable, and identify the role of each of them in achieving the required performance of the organizations and adapt to the rapid environmental changes. The research was applied to the Iraqi Cement State Company one of the formations of the Iraqi Ministry of Industry and Minerals, and based on the importance of the subject matter of the research and the importance of the research sample and company of inquiry, The researcher adopted the descriptive analytical method in completing his research. The sample of the research was Intention
... Show MoreThis Research involves radiological study to assess the marl layer in the Euphrates Formation (Early Miocene) as a raw material for Portland cement industry. Nine wells are drilled penetrating the marl layer to the limestone beneath it. Nine samples were collected from core wells. Each sample represents one well. The concentration of the natural radionuclides 226Ra, 232Th and 40K are 14.91, 5.16 and 223.98 Bq/kg-1, respectively. They are determined by using the technique of gamma-ray spectroscopy with HPGe detector. The radiation doesn't exceed the globally
permissible limits. Then the results were compared with the reported data of other countries and with the world average activity of cement raw materials. The radium equivalent (Rae
This research introduces a developed analytical method to determine the nominal and maximum tensile stress and investigate the stress concentration factor. The required tooth fillets parametric equations and gears dimensions have been reformulated to take into account the asymmetric fillets radiuses, asymmetric pressure angle, and profile shifting non-standard modifications. An analytical technique has been developed for the determination of tooth weakest section location for standard, asymmetric fillet radiuses, asymmetric pressure angle and profile shifted involute helical and spur gears. Moreover, an analytical equation to evaluate gear tooth-loading angle at any radial distance on the involute profile of spur and hel
... Show MoreDissolution of gypsum rock in water is significant, which may result in hydrocarbon reservoir formation and evaporate deposits. However, the complexity of the gypsum dissolution process is still of interest because of its uncleanness that requires more critical analysis. The objectives of this experimental study are emphasis on the dissolution characteristics of gypsum rock under room temperature and by various types of water; namely: deionized, tap, fresh, acidic, well, and normal rainwatre. In addition, the influences of dissolution on gypsum rock's mechanical and physical characteristics. Gypsum rock was obtained from Agjalar area, in the southwest of Sulaymaniyah city, Northern Iraq. Experimental results show that we
... Show MoreBackground: acrylic resin denture base consider a common denture base material for its acceptable cost, aesthetic and easy processing but still has disadvantages including easy of fracture and low impact strength. Material and method: The experimental group was prepared by addition of 15% phosphoric acid 2-hydroxyethyl methacrylate ester (PA2HEME) with polymethyl methacrylate monomer; the experimental groups was compared with the control one. The specimens were prepared according to ADA specification No. 12 with dimension 65 mm x 10 mm x2.5 mm (length x width x thickness respectively). The prepared specimens were tested by three-point flexural strength utilizing Instron Universal Testing Machine (WDW, Layree Technology Co.), Shore D hard
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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 kla were correlated with a mathematical correlation des
... Show MoreThe present study was designed to isolate the microbial community from oil-contaminated sites and other non-oil-contaminated sites which served as control samples in Kerbala city. In addition to test the effect of hydrocarbons on the growth of some types of bacteria. Bacterial genera and species were identified based on their growth on nutrient agar and blood agar as well as biochemical tests. According to the high bacterial growth rate on crude oil, 5 bacterial isolates were selected for further study. Growth of some identified bacteria in Minimal salt medium amended with hydrocarbon as the sole carbon source was investigated. Acinetobacter sp., Pseudomonas aeruginosa, Pseudomonas fluorescens, P
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