A high Tc superconductor with a nominal composition
(Bi1-xPbx)2(Sr1-yBay)2Ca2Cu3O10+δ for (0 £ x £ 0.5) and (0 £ y £ 0.5) was prepared by
a solid state reaction method. The effect of the substitution of Pb for Bi and Ba for Sr and
quenching temperature on the superconductivity has been investigated to obtain the
optimum conditions for the formation and stabilization of the high Tc phase (2223).
The results showed that the optimum sintering temperature for the pure composition is
equal to 875°C and the sintering time is equal to 240h with heating and cooling rate of
60°C/h . Our results indicated that a small amount of (Ba = 0.1) could raise the transition
temperature (Tc), but enhancing Ba to 0.4 has raised the resistivity and the behavior of the
composition converted to semiconductor and ultimately for the composition that has (x =
0.4, y = 0.5) was an insulator. The best value of (Tc = 122 K) is for the composition that
has x = 0.2, y = 0.1.On the other side for Ba free samples increasing of lead content up to
0.3 has rise the transition temperature (Tc = 116 K) but more increases to (0.4, 0.5) causes
a decrease in Tc.
The effect of quenching temperature Tq on the transition temperature Tc of the (Bi1-
xPbx)2(Sr1-yBay)2Ca2Cu3O10+δ was also investigated .
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The study aims to explore the relationship between IFRS S1, S2, and Strategic Managerial Accounting (SMA) practices by building an applied model in an environment where these standards have not yet been implemented. The study focuses on the manufacturing sector in Iraq, as it is the sector most affected by environmental issues. The content analysis methodology was used to extract quantitative indicators from companies’ reports related to sustainability standards. The results showed that the adoption of the Sustainability disclosure Standards (SDS) requires incorporating this information into consolidated and financial disclosure reports. The results of implementing Material Flow Cost Accounting (MFCA) showed that this tool helps reclassif
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The aim of the research is to diagnose the level of awareness and response of the researched sample to the concept of enlightened leadership and strategic alignment, as well as to measure the strength and weakness of the relationships between the independent variable of enlightened leadership and the dependent variable of strategic alignment with its dimensions. Thus, the research problem was defined by the main question of identifying the role played by enlightened leadership in achieving strategic alignment in a number of private Iraqi commercial banks. In light of this, the hypothetical research model was designed, embodying the relationship between the research variables. The descriptive analytical approach was adopted, and a ques
... Show MoreExperimental investigations had been done in this study to demonstrate the effect of natural particles used as a reinforcement material to unsaturated polyester resin. The tensile test and water absorption were investigated according to (ASTM D638) and (ASTM D570), respectively. The influence of sunflower husk and pomegranate husk particles, used as a reinforcement material, on the tensile strength, Young's modulus and water absorption with different weight fraction (3%, 7% and 10%) and particle grain size (50µm, 100 µm and 150 µm), has been investigated. The water absorption of polymer composites was studied by measuring the specimen weight before and after immersion in water for one hundred days. In the experiments of tensile test,
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The experiments were conducted in laboratory conditions of a temperature of 25± 2C and relative moisture of 40± 5 % to evaluate the effectiveness of the cinnamon, lavender and clove essential oils on some biological life aspects of cowpea beetle, C. maculates. Results of the obligative experiment for the effect of the oils on insect adult killing showed that the concentration of 5% caused a mortality percentage averaged 13.33% of the insect males. The mortality percentage of the insect females was 11.3% for the cinnamon and lavender oils. The lavender oil had the lowest effect on adult killing, not exceeding 0. For the effect of the oils on egg laying, clove oil affected the number of eggs highly at the concentration of 5%, result
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The experiments were conducted in laboratory conditions of a temperature of 25± 2C and relative moisture of 40± 5 % to evaluate the effectiveness of the cinnamon, lavender and clove essential oils on some biological life aspects of cowpea beetle, C. maculates. Results of the obligative experiment for the effect of the oils on insect adult killing showed that the concentration of 5% caused a mortality percentage averaged 13.33% of the insect males. The mortality percentage of the insect females was 11.3% for the cinnamon and lavender oils. The lavender oil had the lowest effect on adult killing, not exceeding 0. For the effect of the oils on egg laying, clove oil affected the number of eggs highly at the concentration of 5%, result
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This study was carried out in epidemically field with common reed (Phragmites communis Trin.) plants in the Nassiriah cityThiQur governorate ,during 2009/2010 to investigate the influence of plant growth regulator gibberellin (GA3)and cytokinin (CK) in increasing the efficacy of glyphosate and Fluazifop-butyl in common reed control . Factorial experiment in RCBD was used with three replications in tow Factors . Glyphosate 3500mg .l־¹ gave the higher mean of injury score of common reed and lower mean of common reed shoots , shoots dry weight and rhizome dry weight(3.59,22.01 shoot /0.5m² ,0.57Kg / 0.5m² and 250.50gm /0,5m² ),respectively. All plant growth regulators gaves the higher means of common reed shoots and rhizome dry weight com
... Show MoreIRA Dawood, JOURNAL OF SPORT SCIENCES, 2016 - Cited by 3
Hands have consistently been an important vehicle in the transmission of disease (1). Thus, thorough hand-washing remains the single most important factor in preventing infection specially in hospitals and labs.Twenty-nine non-clinical volunteers (do not work or come in contact with a clinical or hospital setting) that lacked visible skin injuries, eczema or apparent skin disease were used, those subjects were all tested by a material of each of the three used in the study weekly and laboratory tests were done pre- and post washing.All three material were effective , Eugenol extract as effective as the bar and lotion soap. And this was confirmed statistically.Eugenol has a great antibacterial action even in small concentration and t
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يعتقد البعض ان مفهوم العلم يعني الآلات والاجهزة العلمية (تقنيات التعليم) وهي لا تختلف عن مفهوم تكنولوجيا المعلومات , ويعد هذا الاعتقاد خاطئ , لان العلم هو بناء المعرفة العلمية المنظمة والتي يتم التوصل اليها عن طريق البحث العلمي , اما تكنولوجيا المعلومات فهي "التطبيقات العملية للمعرفة العلمية في مختلف المجالات ذات الفائدة المباشرة بحياة الانسان, او هي النواحي التطبيقية للعلم وما يرتبط بها من آلات واجهزة".