Bacteria strain H8, which produces high amount of exopolysaccharide (EPS), was isolated from soil, and identified as strain of Azotobacter chrococcum by its biochemical /physiological characteristics, EPS was extracted, partially purified and used as bioflocculant. The biochemical analysis of the partially purified EPS revealed that it was an alginate. analysis of EPS by Fourier transform infrared spectrometry (FTIR) show that the -OH groups present in bioflocculant are clearly seen at 3433.06 cm-1, the peaks attributed to the -CH3 groups present at 2916.17 cm-1 , and some distinct peaks such as carboxyl group showed strong absorption bands at 1604.66 cm-1, 1411.80 cm-1 and 1303.79 cm-1 indicate the chemical structure of alginate. The effects of various salts, temperature, bioflocculant dosage and pH on the flocculation activity (turbidity removal) were evaluated. When various salts, were used as cation, results showed that CaCl2 and ZnSO4.7H2O enhanced flocculation activity 57.3% and 55.3% respectively compared with CuSO4 and MnCl2 which was 37.5% and 10 % respectively. The bioflocculant had strong thermal stability within the range of 20-100 °C, and the flocculating activity was over 50 %, the maximum flocculation activity was observed at an optimum bioflocculant dosage of 0.25 mL /10 mL (60.8%)., the bioflocculant had highest flocculating activity at alkaline condition pH 10 (77.7 %). After optimization of flocculation conditions, bioflocculant produced was applied to deal with river water and the flocculating activity (turbidity removal) increased to 81%.
The study aimed to reveal the impact of employing the strategy of the talk-ative groups on the achievement and academic tendencies of chemistry forstudents of the fifth grade of applied science for the academic year (2018 -2019), and to achieve this goal the researcher used the experimental methodon the sample of the study consisting of (50) students, prepared achievementtest falls Under (60) paragraphs, and the scale of tendencies for chemistryfalls under (30) paragraphs, and after the researcher completed the researchexperiment according to what was planned:The superiority of the experimental group studied according to the strate-gy of the talkative groups was found in the post-application of the test ofachievement and attitudes of chemis
... Show MoreThe research aims to identify the most important difficulties facing the scientific research in the technical university in the financial, organizational and administrative according to the quality standards according to the paragraphs studied in the questionnaire questionnaire prepared for this purpose, including the research community on the Central Technical University, which includes several technical colleges and technical institutes were selected A sample of the researchers in the Institute of Technical Management where the number of training was 78 teachers took a random sample of researchers amounted to 40% of the questionnaire, and after the collection and classification of data were used statistical means, including the mean ar
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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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(6)
COVID-19 is a disease that has abnormal over 170 nations worldwide. The number of infected people (either sick or dead) has been growing at a worrying ratio in virtually all the affected countries. Forecasting procedures can be instructed so helping in scheming well plans and in captivating creative conclusions. These procedures measure the conditions of the previous thus allowing well forecasts around the state to arise in the future. These predictions strength helps to make contradiction of likely pressures and significances. Forecasting procedures production a very main character in elastic precise predictions. In this case study used two models in order to diagnose optimal approach by compared the outputs. This study was introduce
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(3)
A field study aimed at identifying the degree of satisfaction of secondary school principals with regard to the role of universities and their obstacles in developing their administrative skills. It adopted the descriptive analytical approach. The research community consisted of (249) male and female principals in the schools of Baghdad (Al-Rusafa and Karkh), and the research sample was chosen by the simple random stratified method at a percentage of (40%) of the research community, and the number of the sample was (100) male and female principals. A questionnaire consisting of (40) items distributed between two domains was developed. Its validity and reliability were confirmed. The researcher used the (SPS
... Show MoreThe research aims to diagnose the shortcomings and weaknesses in applying the dimensions of the quality of work life and the extent of their impact on employees’ attitudes and behaviors, and thus their relationship to enhancing their core competencies. The scientific value of the research stems from highlighting the importance of the dimensions of the quality of professional life in improving the productive efficiency of workers in the public sector and raising the level of organizational performance. Because the quality of working life plays an important role in enhancing the core competencies of employees in the public sector, it can also be an incentive or a disincentive for any employee by adapting to the economic and social condit
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The optical detectors which had been used in medical applications, and especially in radioactive treatments, need to be modified studied for the effects of radiations on them. This study included preparation of the MnS thin films in a way that vacuum thermal evaporation process at room temperature 27°C with thickness (400+-10nm) nm and a sedimentation rate of 0.39nm/sec on glass floors. The thin films prepared as a detector and had to be treated with neutron irradiation to examine the results gained from this process. The results decay X-ray (XRD) showed that all the prepared thin films have a multi-crystalline structure with the dominance of the direction (111), the two samples were irradiated with a neutron irradiation source (241Am-9Be)
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(1)
The city has normal natural state, and the man has a usual movement, change and search for the new .Also, the city has a usual change and transform in its time, place and quality (sizes)structures. The city has a solid memory diving into the past and the future and reflects The real present, and this memory has a timing layers change into real materialistic place making the city has accumulated overlapping circles which is hard to break u , and it broadcasts the lockup timing density ,in which there is no visual record precisely, it is just like((the social record)) that evaluates the un visual relationships between the components and parts of the city (community and form) in a visual quiet exhibition and transform change inside.
... Show MoreBackground: 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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