In the present investigation two different types of fiber reinforced polymer composites were prepared by hand lay-up method using three different parameters (curing temperature, pressing load and fiber volume fraction). These composites were prepared from the polyester resin as the matrix material reinforced with glass fibers as first group of samples and mat Kevlar fibers as the second group, both with different volume fractions (4%, 8%, and 12%) of fibers. They were then tested by tensile strength and impact strength. The main objective in this study is to use Taguchi method for predicting the better parameters that give the better tensile and impact strength to the composites, and then preparing composites at these parameters and comparing them with the randomly used once. The experimental and analytical results showed that the Taguchi method was successful in optimizing the parameters that give the highest properties and it can find the most influential parameter regardless of the material used. Also it showed that the volume fraction was the most influential parameter on the tensile and impact strength. The difference between these composites was in the properties values and that the Kevlar composites have higher tensile and impact strength.
One of most the important compounds which have active hydrogen (substrate) is the thiols which used in a wide field in preparation of Mannich bases . A large number of Mannich bases have been prepared as a biologically active compound (pharmaceutical, pesticides, bactericidal, fungicidal and tuberculostatic) and in order to correlate their structure and reactivity with their pharmacological activity such as . It has been reported that the reaction is easily proceeded by using primary and secondary amine beside formaldehyde. But when we tried the reaction of thiols as substrate and formaldehyde and succinimide instead of amine, the reaction did not proceed to give Mannich base but product were methylenene – bis – sulfide . Mann
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Abstract
The target derivative are gentamicin linked with L-Val- L-Ala by an ester linkage. These were synthesized by esterification method, which included the reaction of -OH hydroxyl group on (carbon No.5) of gentamicin with the acid chloride of the corresponding dipeptide, The preparation of new derivative of gentamicin involved protected the primary & secondary amine groups of Gentamicin, by Ethylchloroformate (ECF) to give N-carbomethoxy Gentamicin which was used for further chemical synthesis involving the free hydroxyl groups.
Then prepared dipeptide (L-Val- L-Ala) by conventional solution method in present DCC & HoBt then reacted with thionyl
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This study concluded detection of Toxoplasma gondii in milk, immunologically by using Elisa and nested PCR)nPCR (based on B1 gene, also to investigate the effect of toxoplasmosis, parity, breed and flock on some milk composition in the Iraqi local and Shami goats in the middle of Iraq. A total of 80 milk samples of the lactating goats were collected. Results of this study showed the prevalence of Toxoplasmosis was 21.25% and 28.75% by Elisa and nPCR respectively without significant differences. The sensitivity of Elisa was a low (30.43%) whereas the specificity was a high (82.45%). The degree of agreement estimated by Kappa coefficient revealed a slight agreement (0.14) between two methods. The results indicated that goats infected
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Background: The ideal maxillofacial prosthesis should have fine and thin boundaries that bindwith the surrounding facial structures and possess high tear strength.This study aims to determinethe best percentages of nanofiller (TiO2) and intrinsic pigment (silicone functional intrinsic) thatcould be mixed in as additives to improve the tear strength of Cosmesil M511 andVST50F siliconeelastomers with the least effect on their hardness.Materials and Methods: In this in vitro experimental study, a total of 80 samples, 40 for eachelastomer, were fabricated. Each elastomer sample was split into two equal groups to test for tearstrength and Shore A hardness. Each group consisted of 20 samples, including 10 control sampleswithout additives and 10 e
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The article is final after making all the modifications. 2,259 / 5,000 يهدف البحث إلى قياس وتحليل الفجوة بين الواقع الفعلي لبنود التخطيط والدعم وفق المواصفة (IATF16949:2016) في مصنع البطاريات أحد مصانع الشركة العامة لصناعة وتجهيز السيارات، وكذلك التعرف على نقاط القوة والضعف لبنود التخطيط والدعم وفق المواصفة محل البحث. ينطلق البحث من حاجة الشركة العامة لصناعة وتجهيز السيارات إلى إتباع المعايير العالمية في صناعة السيارات والمنتجات المرتبطة بها،
... Show Moreيتناول هذا البحث موضوع مهم في تاريخ العراق في العهد الملكي يتمثل في الانقلاب العسكري الذي قام به عدد من قادة الجيش العراقي بقيادة الفريق بكر صدقي رئيس أركان الجيش العراقي سنة 1936م وتم تشكيل حكومة من الانقلابيين استمرت حوالي تسعة أشهر وكتب عنها الكثير بعض هذه الكتابات كانت مع الانقلاب وبعضها كانت ضده وجاء هذا البحث ليسلط الضوء على ألصوره الذهنية التي حاولت ان ترسمها الصحف العراقية في حينها وتم دراسة الموضوعات
... Show Moreيتناول البحث الاخلال المسبق واثره في تنفيذ الالتزام العقدي على حساب المدين ـ دراسة مقارنة في القوانين المدنية والقانون الانكليزي
Factors affecting consumer consumerism Iraqi The research aims to shed light on the factors influencing consumer consumerism Iraqi and arranged in terms of the degree of importance in influencing through poll sample, which amounted to (85) members of the shoppers of electrical goods in the markets of Baghdad, Questionnaire has been used as a tool head to collect data and information from the sample surveyed and their answers were analyzed using factor analysis and test ( ), and The research group was the most prominent