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alkej-351
Iraqi Bauxite and Porcalinite Rocks Based Refractory, Preparation and Studying Properties
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Abstract 

Locally natural occurring Iraqi rocks of Bauxite and Porcelanite (after pre calcinations at 1000oC for 1hr) were used, with the addition of different proportions of MgO and Al2O3, to prepare refractory materials. The effects of these additives on the physical and thermal properties of the prepared refractories were investigated.

Many batches of Bauxite/MgO, Bauxite/Al2O3, Bauxite/MgO/Al2O3, and   Porcelanite/ MgO/Al2O3 were prepared. The mixture is milled and classified into different size fractions; fine (less than 45μm) 40%, middle (45-75μm) 40%, and coarse (75-106μm) 20% .                         

X-ray diffraction technique was used to identify the structure of Bauxite and Porcelanite rocks. The samples were formed by semi dry pressing with the addition of few drops of water as a binder. These samples were sintered at 1100oC for 2hrs. Physical properties (linear shrinkage, density and porosity), and the thermal properties (thermal conductivity, diffusivity and specific heat) were measured for all the prepared samples.         

The results show the increasing of density is susceptible to the thermal properties, and also the addition of Al2O3 and MgO to the natural rocks have a limited effect, and the values of the parameters above  for the natural rocks, were in the levels to be used as a refractory material for lining a metal fusion furnaces and other applications.

Keywords: Bauxite, Refractory brick, Porcelanite Stone, Physical properties, Thermal properties.

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Publication Date
Sat Oct 01 2011
Journal Name
Journal Of Engineering
IMPROVED IMAGE COMPRESSION BASED WAVELET TRANSFORM AND THRESHOLD ENTROPY
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In this paper, a method is proposed to increase the compression ratio for the color images by
dividing the image into non-overlapping blocks and applying different compression ratio for these
blocks depending on the importance information of the block. In the region that contain important
information the compression ratio is reduced to prevent loss of the information, while in the
smoothness region which has not important information, high compression ratio is used .The
proposed method shows better results when compared with classical methods(wavelet and DCT).

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Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
Image Watermarking based on Huffman Coding and Laplace Sharpening
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In this paper, an algorithm through which we can embed more data than the
regular methods under spatial domain is introduced. We compressed the secret data
using Huffman coding and then this compressed data is embedded using laplacian
sharpening method.
We used Laplace filters to determine the effective hiding places, then based on
threshold value we found the places with the highest values acquired from these filters
for embedding the watermark. In this work our aim is increasing the capacity of
information which is to be embedded by using Huffman code and at the same time
increasing the security of the algorithm by hiding data in the places that have highest
values of edges and less noticeable.
The perform

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Publication Date
Sun Dec 02 2012
Journal Name
Baghdad Science Journal
Synthesis and Characterization of Derivatives Based on 4, - Dimercaptobiphenyl
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Starting from 4, - Dimercaptobiphenyl, a variety of phenolic Schiff bases (methylolic, etheric, epoxy) derivatives have been synthesized. All proposed structure were supported by FTIR, 1H-NMR, 13C-NMR Elemental analysis all analysis were performed in center of consultation in Jordan Universty.

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Publication Date
Thu Jan 30 2020
Journal Name
Journal Of Engineering
Design and Analysis WIMAX Network Based on Coverage Planning
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In this paper, wireless network is planned; the network is predicated on the IEEE 802.16e standardization by WIMAX. The targets of this paper are coverage maximizing, service and low operational fees. WIMAX is planning through three approaches. In approach one; the WIMAX network coverage is major for extension of cell coverage, the best sites (with Band Width (BW) of 5MHz, 20MHZ per sector and four sectors per each cell). In approach two, Interference analysis in CNIR mode. In approach three of the planning, Quality of Services (QoS) is tested and evaluated. ATDI ICS software (Interference Cancellation System) using to perform styling. it shows results in planning area covered 90.49% of the Baghdad City and used 1000 mob

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Publication Date
Tue Mar 30 2010
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
PC-Based Controller for Shell and Tube Heat Exchanger
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PC-based controller is an approach to control systems with Real-Time parameters by controlling selected manipulating variable to accomplish the objectives. Shell and tube heat exchanger have been identified as process models that are inherently nonlinear and hard to control due to unavailability of the exact models’ descriptions. PC and analogue input output card will be used as the controller that controls the heat exchanger hot stream to the desired temperature.
The control methodology by using four speed pump as manipulating variable to control the temperature of the hot stream to cool to the desired temperature.
In this work, the dynamics of cross flow shell and tube heat exchanger is modeled from step changes in cold water f

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Publication Date
Thu Feb 01 2024
Journal Name
Journal Of Engineering
Experimental Evaluation of Stability and Rheological Properties of Foam Cement for Oil Wells
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Oilwell cementing operations are crucial for drilling and completion, preserving the well's productive life. However, weak and permeable formations pose a high risk of cement slurry loss, leading to failure. Lightweight cement, like foamed cement, is used to avoid these difficulties. This study is focused on creating a range of foamed slurry densities and examining the effect of gas concentration on their rheological properties. The foaming agent and foam stabilizer are tested, and the optimal concentration is determined to be 2% and 0.12%, respectively, by the weight of the cement.

Furthermore, the construction of samples of foam cement with different densities (0.8, 1.0, 1.2, 1.4, and 1.6) g/cc is performed to f

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Publication Date
Mon Mar 01 2010
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The dropping of three zeroes from Iraqi dinar
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           The purpose of this research is to explain the effect of the dropping of three zeroes from Iraqi dinar on the basic role of the dinar and derivative and dynamic in transaction of Iraqi economic. the importance of this research comes from the effect of this operation on the evaluation of the exchange between the individuals of Iraqi society and the other between the Iraqi individuals and the foreign whom use the Iraqi dinar as a tool for exchange also the effect of the operation on the reserves of the Iraqi dinar the results of this research are as the following:-

1-the operation of dropping of zeroes must be associated with increase of the sharing of economic sectors wi

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Publication Date
Sun May 01 2016
Journal Name
Energy Conversion And Management
Stability and thermophysical properties of non-covalently functionalized graphene nanoplatelets nanofluids
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A pioneering idea for increasing the thermal performance of heat transfer fluids was to use ultrafine solid particles suspended in the base fluid. Nanofluids, synthesized by mixing solid nanometer sized particles at low concentrations with the base fluid, were used as a new heat transfer fluid and developed a remarkable effect on the thermophysical properties and heat transfer coefficient. For any nanofluid to be usable in heat transfer applications, the main concern is its long-term stability. The aim of this research is to investigate the effect of using four different surfactants (sodium dodecyl benzene sulfonate (SDBS), sodium dodecyl sulfate (SDS), cetyl trimethylammonium bromide (CTAB), and gum Arabic (GA)), each with three different

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Publication Date
Sun Jan 05 2014
Journal Name
Paripex - Indian Journal Of Research
Effect of heat treatment on the structural and optical properties of CuIn1-xGaxSe thin films
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The structural, optical properties of cupper indium gallium selenite (CuIn1-xGaxSe) have been studied. CuIn1-xGaxSe thin films for x=0.6 have been prepared by thermal evaporation technique, of 2000±20 nm thickness, with rate of deposition 2±0.1 nm/sec, on glass substrate at room temperature. Heat treatment has been carried out in the range (373-773) K for 1 hour. It demonstrated from the XRD method that all the as-deposited and annealed films have polycrystalline structure of multiphase. The optical measurement of the CIGS thin films conformed that they have, direct allowed energy gap equal to 1.7 eV. The values of some important optical parameters of the studied films such as (absorption coefficient, refractive index, extinction coeffici

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Publication Date
Wed Aug 15 2018
Journal Name
Al-khwarizmi Engineering Journal
Construction and Characterization of Organic Solar Cell and Study the Operational Properties
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This article reviews the construction of organic solar cell (OSC) and characterized their optical and electrical properties, where indium tin oxide (ITO) used as a transparent electrode, “Poly (3-hexylthiophene- 2,5-diyl) P3HT / Poly (9,9-dioctylfluorene-alt-benzothiadiazole) F8BT” as an active layer and “Poly(3,4-ethylenedioxythiophene)-poly (styrene sulfonate)” PEDOT: PSS which is referred to the hole transport layer. Spin coating technique was used to prepared polymers thin film layers under ambient atmosphere to make OSC.  The prepared samples were characterized after annealing process at (80 ͦ C) for (30 min) under non-isolated circumference. The results show a value of filling factor (FF) of (2.888), (0.233) and (0.28

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