Both normally developed insects and insects developed after cessation of eggs growth were
used in this work. Cessation of eggs growth occurred following abnormal conditions, which
lasted for 3.5 months before developing into adults, due to the war led by the U.S. and her
alliances against Iraq. These insects showed low rates of water contents and an active response
to water loss. Therefore their tolerance of desiccation was weak. In addition, they had an active
ability to restore their water loss quickly, after return them to a culture, this indicates that some
changes occurred in their integumentary properties were not permanent and took their turn
within one population only, but may or may not serve this population. That depends on the
climatic factors.
This study presents a comprehensive set of laboratory works for the examined soil layers extracted from Baghdad city (specifically from Alkadhimya, Alaitaifiya, and Alhurriya) to illustrate their engineering properties. The researchers have adopted the unified soil classification system for soil classification purposes. Also, the direct shear test was performed for soil samples with various degrees of saturation (0%, 25%, 50%, 75%, and 100%). The test results have shown a significant reduction in cohesion property with higher moisture content within soil samples. Also, a noticeable reduction in angle of internal friction value has occurred with such changes. Furthermore, it has been found that the bearing capacity of unsaturated soi
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In this research the effect of cooling rate and mold type on mechanical properties of the eutectic
and hypoeutectic (Al-Si) alloys has been studied. The alloys used in this research work were (Al- 12.6%Si
alloy) and (Al- 7%Si alloy).The two alloys have been melted and poured in two types of molds with
different cooling rates. One of them was a sand mold and the other was metal mold. Mechanical tests
(hardness, tensile test and impact test) were carried out on the specimens. Also the metallographic
examination was performed.
It has been found that the values of hardness for the alloys(Al-12.6%Si and Al-7%Si) which poured in
metal mold is greater than the values of hardness for the same alloy when it poured in a heated
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Low- and medium-carbon structural steel components face random vibration and dynamic loads (like earthquakes) in many applications. Thus a modification to improve their mechanical properties, essentially damping properties, is required. The present study focuses on improving and developing these properties, significantly dampening properties, without losing the other mechanical properties. The specimens used in the present study are structural steel ribbed bar ISO 6935 subjected to heating temperatures of (850, 950, and 1050) ˚C, and cooling schemes of annealing, normalizing, sand, and quenching was selected. The damping properties of the specimens were measured experimentally with the area under the curve for the loadi
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This study evaluates the efficacy of pullulan, a bacterial polysaccharide extracted from a local Micrococcus luteus isolate, in preserving the oxidative stability of unrefined sunflower oil. Using peroxide value (PV) and thiobarbituric acid value (TBA) as metrics. Five treatments were compared against a traditional antioxidant, butylated hydroxytoluene (BHT), and a control. Results demonstrated that the use of 800 ppm pullulan significantly inhibited oxidative degradation of the unrefined sunflower oil, particularly at 20°C storage. Peroxide values for 800 ppm pullulan (1.91 mEq.kg-1 at 20°C; 2.88 mEq.kg-1 at 50°C) were slightly higher than BHT (1.82 and 1.99 mEq.kg-1) but markedly lower than the control (4.49 and 3.59 mEq.kg-1).
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يأتي الاستخدام العالمي لبولي ميثيل ميثاكريلات (PMMA) كمادة أساسية لأطقم الأسنان من سهولة المعالجة والإصلاح والتوافق الحيوي والمظهر الجمالي الممتاز. ومع ذلك ، فإن أوجه القصور في مواد البوليمر ، مثل الخواص الميكانيكية والفيزيائية غير كافية. كان الغرض من هذه الدراسة هو تقييم القوة المستعرضة وقابلية البلل PMMA بعد الاختلاط مع جزيئات الزركونيا و PMMA المبلمرة [ZP] كمواد مالئة بنسبة مختلفة. المواد والأساليب: تم اقترا
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Zinc Oxide thin film of 2 μm thickness has been grown on glass substrate by pulsed laser deposition technique at substrate temperature of 500 oC under the vacuum pressure of 8×10-2 mbar. The optical properties concerning the absorption, and transmission spectra were studied for the prepared thin film. From the transmission spectra, the optical gap and linear refractive index of the ZnO thin film was determined. The structure of the ZnO thin film was tested with X-Ray diffraction and it was formed to be a polycrystalline with many peaks.
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The research aims to study some of the human characteristics of the state of Singapore to know the impact of these characteristics on the strength of the state, its development and. The research included two aspects, theoretical and analytical, using the descriptive analytical method, force analysis method, as well as the historical method. The data was analyzed according to mathematical equations, including the size of the country's population, the extraction of the population growth rate and the concept of age structure, where some indicators related to this concept have been explained. The researcher reached a set of results, the most important of which were: that the population size of the state of Singapore in the period between (19
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