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bsj-2993
Acoustic and Thermal Insulation of Nanocomposites for Building Material: Improvement Of Sound And Thermal Insulation Properties Of Nanocomposite
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This work aims to enhance acoustic and thermal insulation properties for polymeric composite by adding nanoclay and rock wool as reinforcement materials with different rations. A polymer blend of (epoxy+ polyester) as matrix materials was used. The Hand lay-up technique was used to manufacture the castings. Epoxy and polyester were mixed at different weight ratios involving (50:50, 60:40, 70:30, 80:20, and 90:10) wt. % of (epoxy: polyester) wt. % respectively. Impact tests for optimum sample (OMR), caustic and thermal insulation tests were performed. Nano clay (Kaolinite) with ratios ( 5 and 7.5% ) wt.% , also hybrid reinforcement materials involving (Kaolite 5 & 7.5 % wt.% + 10% volume fraction of rockwool ) were added as reinforcement materials to the optimum sample. Results of impact test prove that the optimum sample has (80:20) wt. % of mixing ratio of (epoxy: polyester) wt. % for using as matrix materials. Moreover, the adding of nanoclay (Kaolinite) with ratio (7.5 wt.%) leads to the highest sound insulation. The sound intensity started at (99.8) db at 100 Hz, and reached to (101.3) db at 10000 Hz., which is much lower than the values obtained from the un-reinforced blend, of which the sound intensity started at (107.2) db and reached to (108.7) db., at the same range of frequencies. Thermal conductivity results show that the optimum matrix with (7.5 %) wt. % has the lowest value about (0.443 k.w\m .c).

        The results show that the blend reinforced with nano clay in a weight fraction (7.5)% has the best sound insulation, so that the sound intensity started at (99.8) db at 100 Hz., and reached (101.3) db at 10000 Hz., which is much lower than the values obtained from the unreinforced blend, of which the sound intensity started at (107.2) db and reached (108.7) db., applying the same range of frequencies. The same casting (blend+7.5% nanoclay) showed the lowest value of thermal conductivity (xxxx) W.m°C in comparison with castings that were made of unreinforced blend and those  hybridized with rockwool.

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Publication Date
Sat Mar 01 2008
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
External Auditor of responsibility for financial failure And the discontinuity of Company
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Accountancy unit is looked is upon as unit that established for the purpose achieve it goals and programmers for unlimited time. Unless otherwise take place such as liquation whether voluntary or mandatory.  Thus going concern logic is considered to be the logical foundation witch the familiar accounting principles are based upon.  The future of a Company real its financial statues and position and the extent of it ability to face events in future.  Hence the success and continuity its activities depend on the extent of the company activity to generate profits. And its ability to retain appropriate liquidity to serve its debts.

Therefore financial statements of the company consider to be on

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Publication Date
Mon Apr 01 2019
Journal Name
Journal Of Engineering
The Influence of the Preparation and Stability of Nanofluids for Heat Transfer
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Recently the use of nanofluids represents very important materials. They are used in different branches like medicine, engineering, power, heat transfer, etc. The stability of nanofluids is an important factor to improve the performance of nanofluids with good results. In this research two types of nanoparticles, TiO2 (titanium oxide) and γ-Al2O3 (gamma aluminum oxide) were used with base fluid water. Two-step method were used to prepare the nanofluids. One concentration 0.003 vol. %, the nanoparticles were examined. Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and X-ray diffraction (XRD) were used to accomplish these tests. The stability of the two types of nanofluids is measured by

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Publication Date
Sat Apr 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Center of Urban and Regional Planning for postgraduate Studies - University of Baghdad
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Project deal with the study of the suitability of the planning standards of the select sites for sports facilities for the holy city of Karbala and the extent of convergence and divergence between these standards and points of strength and weakness in each of these standards.

It was found that there was a lack of the   role given to the sports as a kind of luxury does not deserve to spend money and efforts, and was then incorporated with a lot of entertainment services by planners.

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Publication Date
Sat Jun 30 2018
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Prediction and Correlations of Residual Entropy of Superheated Vapor for Pure Compounds
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Prediction of accurate values of residual entropy (SR) is necessary step for the
calculation of the entropy. In this paper, different equations of state were tested for the
available 2791 experimental data points of 20 pure superheated vapor compounds (14
pure nonpolar compounds + 6 pure polar compounds). The Average Absolute
Deviation (AAD) for SR of 2791 experimental data points of the all 20 pure
compounds (nonpolar and polar) when using equations of Lee-Kesler, Peng-
Robinson, Virial truncated to second and to third terms, and Soave-Redlich-Kwong
were 4.0591, 4.5849, 4.9686, 5.0350, and 4.3084 J/mol.K respectively. It was found
from these results that the Lee-Kesler equation was the best (more accurate) one

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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
PREPARATION OF NITRATION DERIVATIVES OF BILE SALTS AND ACIDS FOR MEDICAL USE
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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.

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Publication Date
Sun Feb 03 2019
Journal Name
Journal Of The College Of Education For Women
Thinking Styles And Its Relationship With The Need for Cognitive for Students of University
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This study aims to recognize the most common thinking styles and level of the need for cognitive university students , the relation between thinking styles and the need for cognitive, and there are differences according to gender .The sample consists of (250) males and females university students for the academic year (2013-2014), and the researcher uses two scales;" thinking styles scale (Harison &Bramson, 1986), and the need for cognitive scale" (Cacioppo, Petty & Kao , 1996).
The results show that there is difference in the range of the prevalence of the thinking styles among university students , the scientific thinking style is the most common , the students have got the arrange level of the need for cognitive , and there

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Publication Date
Wed Jun 29 2022
Journal Name
College Of Islamic Sciences
Evidence for monotheism in Islam and the Qur’an and the meaning of the names and attributes and their unification
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This topic is considered to be of a high degree of importance to every Muslim, and its importance is due to the fact that monotheism is:

Prove that God Almighty is the God who created everything and everything opposite to monotheism is polytheism, and it is taking other than God Almighty as a deity.

Therefore, we have to know the concept of God. If he is known, then he knows the concept of monotheism and the concept of polytheism

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Publication Date
Sun Dec 17 2017
Journal Name
Al-khwarizmi Engineering Journal
Study the Effect of Different Reinforcements on the Damping Properties of the Polymer Matrix Composite
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In this research, damping properties for composite materials were evaluated using logarithmic decrement method to study the effect of reinforcements on the damping ratio of the epoxy matrix. Three stages of composites were prepared in this research. The first stage included preparing binary blends of epoxy (EP) and different weight percentages of polysulfide rubber (PSR) (0%, 2.5%, 5%, 7.5% and 10%). It was found that the weight percentage 5% of polysulfide was the best percentage, which gives the best mechanical properties for the blend matrix. The advantage of this blend matrix is that; it mediates between the brittle properties of epoxy and the flexible properties of a blend matrix with the highest percentage of PSR. The second stage

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Effect of thickness on optical properties of pure Epoxy Resin plates
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In this study, Epoxy Resin plates was prepared by mixing epoxy(A) and hardner(B)with ratio(A:B) (3:1) with different thickness (0.3-0.96)cm. The effect of thickness on optical properties have been studied (absorption ,transmission ,reflectance) also the optical constant were found like (absorption coefficient, extenuation coefficient and refraction index) for all of the prepared plates. The results have shown that by increasing the thickness of plates., the absorption intensity increase in which at plates thickness (0.3-0.96)cm the absorption intensity were(1.54-1.43) respectively, and since absorption peak for epoxy occur in ultraviolet region and exactly at wavelength(368)nm and energy gap(Eg=3.05 eV) thus their good transmittance in the

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Publication Date
Fri Aug 07 2020
Journal Name
Key Engineering Materials
The Effect of Particle Size Distribution on some Properties of Gypsum
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Gypsum is one of the important construction materials in Iraq in plastering surfaces and gypsum board , the ability of gypsum to give a comfortable an aesthetic ambiance as a construction material increase the need of gypsum , The particle size , total surface area and particle size distribution were factors affecting plaster properties used for construction properties . In this study gypsum paste was used with different mixing ratios of particle size and studied the physical properties of these types of pastes named (standard consistency ,setting time ,density) and compressive strength . The results showed that the water to gypsum ratio increased with increasing the fineness of the gypsum to (0.75%) and the setting time to the maxi

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