This research aims to investigate the thermal performance of different thermal composite insulators, wrapped around a closed-loop copper pipe (CLP). To achieve this aim a system was designed and manufactured. It is consisted of closed water tank insulated by Rock Wool, and supplied with two electric heaters, two thermostat, a flow meter, a water pump, digital temperature scales, and four series of (CLP).
Six insulators were prepared namely; composites of Impregnated Fiberglass with Elastoclad and foaming Rubber (FER), Impregnated Fiberglass with Elastoclad resin and Polymeric Membrane (FEM), Impregnated Fiberglass with Polyurethane thermoset resin and Foaming Rubber (FUR), Impregnated Fiberglass with Polyurethane thermoset resin and Polymeric Membrane (FUM), Fiberglass woven tape (F) , and foaming rubber tape (R). Thermal conductivities of all composite specimens were measured by Lee's Disc device and their thermal performances were evaluated by measuring inlet and outlet temperature ΔTw at different flow rates. It was found from all test results that ΔTw decreased as flow rate increased.
The optimum result was obtained for the (FER) insulator at flow rate 8 L/min where ΔTw = 0.8 oC (efficiency η = 99 %).
Thermal efficiency of the prepared insulators was according to the following sequence:
FER > FEM > FUR > FUM >R > F
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The paper discusses the lack of a uniform definition of politeness due to the constant tension between its universality and language specificity, and argues that some of the theoretical debate could be resolved if the distinction between politeness as a commonsense notion and politeness as a theoretical construct were clearly addressed and acknowledged in the research.
The title takes its realistic connotations with its symbols, slogans and historical extensions in Iraq, also, the repercussions of the organic crisis that afflicted it for almost half a century, especially after the abortion of the July 14 Revolution and the spread of the culture of weapons, violence and death that we are living in Iraq nowadays.
The topic is suitable for critical analytical studies carried out by specialists in scientific and academic research centers and cultural institutions because they have an important feasibility at the strategic cultural level in Iraq, the Middle East and the world.
Research in Iraq has fallen to the extreme and is no longer effective, to the extent that it represents a severe cri
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Current research strives to achieve the following aims:
- Develop a scale for dominant values of Tikrit university students.
- Measuring the dominant of Tikrit university students.
- Identifying the significant differences among dominant values of Tikrit university students according to(sex, specialty, time).
- Measuring the dominant values of each one of the six fields of the scale.
- Identifying the differences in dominant values of each field according to the sex variables.
The current research has limi
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The objective of the research is to identify the nature of voluntary disclosure of insurance services and its impact on the financial performance of Iraqi insurance companies by knowing the relationship between increasing disclosure of financial services and financial performance indicators of insurance companies.In order to achieve this objective, the research was applied to a sample of the Iraqi insurance companies listed in the Iraqi Stock Exchange (Al Amin Insurance Company, Al Ahlia Insurance, Dar Al Salam Insurance, Gulf Insurance, Al Hamra Insurance) and based on their published financial statements (2014-2015) ) And by analyzing the sample lists were connected to the research objectives.The main conclusion of the study is that in
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The derivatives formed after the successive acetylation, esterification and nitration reactions to cholic, deoxycholic, and taurocholic acids were identified to be of the following general strucure: Colt, Where RI=NO3, OH, 0=, or CH3COO. R2=H, NO3, OH, 0-=, or CH3COO. R3=H, NO3,01-1, 0=, or CH3COO. R4=OH, NH(CH2)2S03Na, NH(CH2)2S03H, or OMe. By using U.V-visible and I.R spectrophotometry . The number of hydroxyl groups was determined, purity was checked from T.L.C, Most of these derivatives will find pharmaceutical application.
Pore volume, pore diameter, and pore volume distribution of three of Iraqi natural clay deposites were measured using mercury intrusion porosimetry .The clays are white kaolin, colored kaolin, and bentonite .The results showed that the variation of the pore area of the clay deposites followed the following order :- Coloured Kaolin > White Kaolin > Bentonite While the pore volume may be arranged as in the following sequence:- White Kaolin > Coloured Kaolin >Bentonite Also , Bentonite exhibits the narrow range pore size distribution than the white and coloured kaolin.
This paper deals with the nonlinear large-angle bending dynamic analysis of curved beams which investigated by modeling wave’s transmission along curved members. The approach depends on the wave propagation in one-dimensional structural element using the method of characteristics. The method of characteristics (MOC) is found to be a suitable method for idealizing the wave propagation inside structural systems. Timoshenko’s beam theory, which includes transverse shear deformation and rotary inertia effects, is adopted in the analysis. Only geometrical non-linearity is considered in this study and the material is assumed to be linearly elastic. Different boundary conditions and loading cases are examined.
From the results obtai
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