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 research is conducted on target of investigating the role of growth strategy via diversification in value maximization of a firm in terms of controversies literatures had witnessed. Using a descriptive approach for analyzing and verifying the harmony of variables of research and their conceptualized logic , it could be reached to many conclusions agreed in their essence upon that the related diversification has the major role in value maximization of a firm and the wealth of its owners .
After 2003, Iraq witnessed new challenges represented by the predominance of sectarian discourses, hatred and extremism at the expense of moderate political discourse and the predominance of sub-affiliations and external agendas at the expense of national affiliation, which led to the creation of an unsafe or stable environment dominated by the character of violence and terrorism. Moderate discourse would work to fuse sub-affiliations into one melting pot in which it would be the first loyalty to the homeland and not to the tribe, party or sect... Etc., and this in turn will contribute to promoting peaceful coexistence between the various other sub-affiliations within the framework of one community construction
The objective of the research is to determine the nature of the strategic direction of the institution and its impact on enhancing the indicators of institutional performance. The strategic direction is the main purpose for which it was found. Therefore, it is the main engine for all activities and tasks that the institution can carry out to achieve its objectives within the environment in which it operates. The promotion of corporate performance indicators is one of the major challenges that senior management must address in order to help the organization invest its human resources in the best possible way.
The research problem was determined by means of the intentional sample, consisting of (33) members
... Show MoreInternational trade in services is becoming increasingly important as it is an economic activity that deals with invisible trade, which has become increasingly important in the balance of international trade. The establishment of the WTO is a starting point in international trade relations. It is responsible for all aspects of international trade, , And in view of the continued increase in international trade in services, the need for more internationally recognized rules has become more urgent, especially as it has been increasingly proven that the traditional framework of public services is inadequate to operate some of the most dynamic and innovative sectors of the economy. (GATS) to be the regulatory framework for this sector
... Show MoreReducing global warming potential (GWP) of refrigerants is needed to the decrease of ozone-depleting of refrigeration systems leakages. Refrigerant R1234yf is now used to substitute R134a inside mobile air conditioning systems. Thermodynamic properties of R1234yf are similar to R134a. Also, it has a very low GWP of 4, compared to 1430 for R134a, making it a proper choice for future automobile refrigerants. The purpose of this research is to represent the main operating and performance differences between R1234yf and R134a. Experimental analysis was carried out on the automotive air conditioning system (AACS) with 3 kW nominal capacity, to test and compare the performance of R134a with R1234yf. Experiments were accomplish
... Show MoreTeachers' self-efficacy plays a very important role in the process of teaching English language, and teachers have primary role in determining what is needed or what would work best with their students. The sample consists of eighty-seven English language teachers in secondary schools in Baghdad/Kaarkh2. Self-efficacy questionnaire of fifteen items was constructed. Face, content validity and reliability were verified. Then, pupils' marks for the first semester were taken as their achievement.The main finding of the study indicates that:
English language teachers' self-efficacy has effect on their pupils' achievement.
In the light of the findings of the present study, several conclusions, recommendations and suggestions for further
The occurrence of two species of the genus Myxobolus Bütschli, 1882 (Myxozoa: Myxosporea) for the first time in Iraq from freshwater fishes.
Polyethersulfone (PES) ultrafiltration membrane blending NaX zeolite crystals as a hydrophilic additive was examined for zinc (II) and lead ions Pb (II) removal from aqueous solutions. The effect of NaX zeolite content on the permeation flux and removal efficiency was studied. The results showed that adding zeolite to the polymer matrix enhanced the permeation flux. The permeation flux of all the zeolite/PES matrix membranes was higher than the pristine membrane. No significant improvement was observed in the removal of Zn (II) ions using all prepared membranes as the removal percentage did not raise above 29.2%. However, the removal percentage of Pb (II) ions was enhanced to 97% using a membrane containing 0.9%wt. zeolite. Also, it was
... Show MoreFatty Acid Methyl Ester (FAME) produced from biomass offers several advantages such as renewability and sustainability. The typical production process of FAME is accompanied by various impurities such as alcohol, soap, glycerol, and the spent catalyst. Therefore, the most challenging part of the FAME production is the purification process. In this work, a novel application of bulk liquid membrane (BLM) developed from conventional solvent extraction methods was investigated for the removal of glycerol from FAME. The extraction and stripping processes are combined into a single system, allowing for simultaneous solvent recovery whereby low-cost quaternary ammonium salt-glycerol-based deep eutectic solvent (DES) is used as the membrane phase.
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