A series of overbased magnesium fatty acids such as caprylate, caprate, laurate, myristate, palmitate, stearate and oleate) were synthesized by the reaction of the fatty acids with active – 60 magnesium oxide and carbon dioxide (CO2) gas at 60 oC in the presence of ammonia solution as catalyst, toluene / ethanol solvent mixture (9:1vol/vol) was added.
The prepared detergent additives were characterized by FTIR, 1HNMR and evaluated by blending each additive in various concentrations with medium lubricant oil fraction (60 stock) supplied by Iraqi Midland Refineries Company. The total base number (TBN, mg of KOH/g) was determined, and the results of TBN were treated by using two-way analysis of variance (ANOVA) test. It was found that the number of carbons in the fatty acid (C8-C18) used for overbased detergent preparation had slight effect on the TBN of the oil, while detergent concentrations (1-5% wt/wt) had a significant effect on the TBN of the blended oil.
The oxidation stability of the oil blends with 2% of overbased magnesium palmitate and overbased magnesium stearate detergents was evaluated, and the results showed that these blends gave higher oxidation stability compared with the blends with standard antioxidant supplied by Midland Refineries Company.
الخلاصة
تعد الانتخابات بمثابة الطريق المؤدي إلى الديمقراطية كونها النمط الأكثر شيوعاً لمشاركة المواطنين في الحياة السياسية للبلدان واختيار ممثليهم في المجالس التشريعية، حيث أن مطلب إجراء انتخابات حرة ونزيهة لم يعد مطلباً داخلياً فحسب بل مطلباً دولياً يصرّ المجتمع الدولي على الوفاء به وهذا يلقي على عاتق كل دولة أن تضع من الضمانات ما يكفل ممارسة هذه الانتخابات ب
... Show MoreThe aim of research is to identify the effect of using Waks strategy upon acquiring the psychological concepts and mind habits for students in the college of education. An experimental design with a partial adjustment of two experimental and control groups as well as a posttest were employed. The researcher divided the study sample into two groups: group one consisted of (38) students to represent the experimental group that was taught according to the waks strategy, and group two consisted of (35) students to represent the control group that was taught according to the traditional method. The sample was chosen based on some variables namely (Intelligence, Prior knowledge). The researcher has designed the research tools as th
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... Show MoreLinear regression is one of the most important statistical tools through which it is possible to know the relationship between the response variable and one variable (or more) of the independent variable(s), which is often used in various fields of science. Heteroscedastic is one of the linear regression problems, the effect of which leads to inaccurate conclusions. The problem of heteroscedastic may be accompanied by the presence of extreme outliers in the independent variables (High leverage points) (HLPs), the presence of (HLPs) in the data set result unrealistic estimates and misleading inferences. In this paper, we review some of the robust
... Show MoreDoses for most drugs are determined from population-level information, resulting in a standard ?one-size-fits-all’ dose range for all individuals. This review explores how doses can be personalised through the use of the individuals’ pharmacokinetic (PK)-pharmacodynamic (PD) profile, its particular application in children, and therapy areas where such approaches have made inroads.
The Bayesian forecasting approach, based on population PK/PD models that account for variability in exposure and response, is a potent method for personalising drug therapy. Its potential utility is eve
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Electrocoagulation is an electrochemical process of treating polluted water where sacrificial anode corrodes to produce active coagulant (usually aluminum or iron cations) into solution. Accompanying electrolytic reactions evolve gas (usually as hydrogen bubbles). The present study investigates the removal of phenol from water by this method. A glass tank with 1 liter volume and two electrodes were used to perform the experiments. The electrode connected to a D.C. power supply. The effect of various factors on the removal of phenol (initial phenol concentration, electrode size, electrodes gab, current density, pH and treatment time) were studied. The results indicated that the removal efficiency decreased as initial phenol concentration
... Show MoreChildhood is characterized by ahigh privacy in the life of the child overall educational institutions in the world. Based on this specificity, modern education begins with a holistic vision of the child through all developmental aspects (moral, religious, emotional, social, linguistic, physical, health, and mental). This integration could be achieved through taking into consideration the needs and rights of children and developing curricula that consider these needs and capacities to provide opportunities for developing and supporting the developmental aspects of the child. The contemporary technological developments in the field of computer and the Internet have brought with it new forms, ideas, and problems for children in recent years
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