The varied thermal conductivity (insulation) of silica aerogel with heating for different pH has been investigated, it has been depended on ambient pressure drying method in the preparing silica aerogel samples, also six different pH of samples (1, 2, 3, 7, 8 and 9) were treated under five degree of heating with (50,100,150,200 and 250) ᴼC. This technique is important to test the carry-outs hydrophobic silica to temperature without high-quality material changes in the basic characteristics. The hot-wire technique is used in this work to examine the thermal conductivity, Fourier Transform Infrared Spectroscopy (FTIR) depended to characterize the bonds and their artificial by heating. Results show that the samples affected by heating through decreasing the density leading to obtaining more insulation metal, moreover varied pH is an important role in thermal conductivity. The average thermal conductivity of all aerogel samples in this work is (0.01- 0.0061 mW m-10 C-1) this means that it is still below thermal conductivity for air equals to (0.02257) mW m-10 C-1 . Meanwhile, we concluded that the insulation property of silica aerogel is affected by heat treatment and gives it more thermal insulation property.
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
The present study aims to investigate the long-term histopathological, and physiological effects of different concentrations of a commercially available energy drink (Tiger) on liver and kidney of young mice. Sixteen Balb/c male mice,6 -week old, were divided into 4 groups (n=4). Two groups consumed the energy drink at a concentration of 28µl energy drink/ml water. One group were killed after 10 days (T1), another group were killed after 20 days (T2). Other group of mice consumed the energy drink at a final concentration of 14µl/ml for 20 days (T3). The last group was provided only with water and served as control. Mice of all groups drank around 3 ml per day. The histopathological study on liver of treated groups showed many changes s
... Show Moreالسياسة التركية تجاه عراق ما بعد الانتخابات
The subject of this thesis acquired it's importance from many sides most
important of it , it's the nature of the relationship between Iraq-Syria relation
itself . which is basic on many close and fare relationship between them upon
the history , and also the changes that happened in global and regional area
after the 11th September 2001 and the changes of the American strategy upon
Syria , and the trying of the united states to qualify the Syrian role inside its
regional in the meddle east upon the changes that imposing by the united
states which is the most important event was the occupation of Iraq .
The importance of this subject is also due to the occupation of the united
states upon the Iraq on April 2003
دراسة التسلح النووي مفهوم واهميه وأبعاد ودراسة القدرات النووية لكوريا الشمالية وتأثيراته الدولية والإقليمية
إن التعبير ينوء بأثقال كبيرة ، وهذه المشكلة قد تتضاعف ،لأنَّ التعبير يحتاج إلى مها ا رت " لم
تنجح المدرسة في تنميتها تنمية صحيحة " ولأنّهُ يصطدم بعوامل معوقة متعددة منها ثنائية اللغة ،
وكثافة الصفوف ، وغياب المنهج ، وٕاهمال التصحيح، ووضع المدرس لكلمة "لوحظ" من غير
ملاحظة شيء وقلة الحصص ، وضعف الربط بين فروع اللغة ، والتساهل في إعداد المدرس.
وقد كان من نتائج د ا رسة أجرتها المنظمة العربية للتربية والثقافة
Presupposition, which indicates a prior assumption, is a vital notion in both semantic and pragmatic disciplines. It refers to assumptions implicitly made by interlocutors, which are necessary for the correct interpretation of an utterance. Although there is a general agreement that presupposition is a universal property of Language, there are various propositions concerning its nature. However, this research work proposes that presupposition is a contextual term, thus, is more pragmatic than semantic in its nature.Although Semantics and Pragmatics are two distinct disciplines, they are interrelated and complementary to each other, since meaning proper involves both, and since there is no clear borderline between the two disciplines. How
... Show MoreThis paper presents a sight about the chemical structure deformation of poly (ethylene-co-vinyl acetate) (EVA) samples according to the change ratio of rate constant values. Spectroscopy kinetics fluorescence curves are fitted for two characteristic wavelength domains of fluorescent intensities. The short wavelengths (320-400 nm) domain show spectra overlapping, while at long wavelengths (400-800 nm) domain spectra are arranged in regular for each specific accelerated aging time. The ratio of kinetics rate constant at long wavelengths to kinetics rate constant of short wavelengths is the criterion of the degree chemical structure deformation. Molar extrin
... Show MoreAbstract: In the present work, the heat transfer of Nano Aluminum Oxide -NAO- has been studied practically to define the appropriate insulation conditions. This study focuses on finding of the amount of heat transfer through a glass substrate that is coated with nanoalumina doped on PMMA matrix. The optical and thermal properties were systematically investigated. The density of heat flow rate, was calculated in the range values (240-260) W/m2 while the optimum values confine between (250-260) W/m2 at temp. (25-35)Co. The results showed that the thermal insulation of the sample was significantly enhanced at temp. (30-50)Co. The simulated net heat transfer through window decreased linearly with incr
... Show More