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Performance Estimation of Heat Exchanger Operates By Evaporative Cooling Manner
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        In this study the design and installation of evaporative air cooler was carried out using completely outdoor air (fresh air) according to two stage evaporative cooling principle. The laboratory equipment was installed by designing and manufacturing a cross flow plate heat exchanger, where aluminum plates used for this purpose with dimensions (50 × 30 × 40 cm). The surfaces of heat exchanger were covered by sawdust from wetted channels side, to increase the percentage of wetting these surfaces and hence improve the performance and efficiency of air cooler.

        An experimental study was carried out to estimate the performance of cooling system, where some of the dominant effective parameters were studied like air flow rate and flow rate and effect the static pressure drop of air and the heat transfer of performance .Air flow rate was ranged between (142.90 to 1461.50 m3 / hr) and water flow rate was varied from (144 L / hr) to (1050 L / hr).

        The experimental results showed that the optimum flow rate of air prepared by the air cooler is (824.7 m3 / hr), As it to be seen from the study that treating the heat exchanger surfaces by sawdust improves the air cooler efficiency about (10 %), but in the other hand leads to increase the static pressure drop in proportion (21%) approximately, and hence increase consumed power about (9 %).The results also show the air cooler can not be used in regions that have moisture content accedes (11.90 g moisture/kg dry air).

 

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Publication Date
Mon Oct 12 2026
Journal Name
Journal Of Baghdad College Of Dentistry
The Effect of Zirconium Silicate Nanopowder Reinforcement on Some Mechanical and Physical Properties of Heat Cured Poly (Methyl Methacrylate) Denture Base Materials
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Background: Polymethylmethacrylate (PMMA) has relatively unsatisfactory mechanical properties such as low flexural strength and impact strength also dimensional instability. Material and method: Zirconium silicate nanoparticles were coated with a layer of trimethoxysilylpropylmethacrylate (TMSPM) before sonication in monomer (MMA) with the percentages 1% and 1.5% by weight then mixed with powder using conventional procedure, (150) samples were prepared and divided into three groups, each group consisted of (50) samples, the first group prepared from PMMA without addition (control), another group with the addition of 1% wt Zrsio4 nanoparticles (experimental) and the third one with 1.5% wt Zrsio4 nanoparticles (experimental). Each group

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Publication Date
Mon Oct 12 2026
Journal Name
Journal Of Baghdad College Of Dentistry
Effect of addition ZrO2-Al2O3 nanoparticles mixture on some properties and denture base adaptation of heat cured acrylic resin denture base material
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Background: The PMMA polymer denture base materials are low mechanical properties, adaptation of the denture base to underlying tissue is important for retention and stability of denture. The aim of the study was toevaluate the effect of mixtureZrO2-Al2O3 nanoparticles on impact strength, transverse strength, hardness, roughness, denture base adaptation of heat cured acrylic resin denture base material. Materials and methods: One hundred (100) specimens were prepared, the specimens were divided into five groups (20 specimens to each) according to the test type, each group was subdivided in to two subgroups (control and experimental) each subgroup consist of 10 specimens, the experimental group included mixture of 2% (ZrO2-Al2O3ratio2:1) b

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Publication Date
Tue Mar 30 2021
Journal Name
Journal Of Economics And Administrative Sciences
Using Iterative Reweighting Algorithm and Genetic Algorithm to Calculate The Estimation of The Parameters Of The Maximum Likelihood of The Skew Normal Distribution
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Excessive skewness which occurs sometimes in the data is represented as an obstacle against normal distribution. So, recent studies have witnessed activity in studying the skew-normal distribution (SND) that matches the skewness data which is regarded as a special case of the normal distribution with additional skewness parameter (α), which gives more flexibility to the normal distribution. When estimating the parameters of (SND), we face the problem of the non-linear equation and by using the method of Maximum Likelihood estimation (ML) their solutions will be inaccurate and unreliable. To solve this problem, two methods can be used that are: the genetic algorithm (GA) and the iterative reweighting algorithm (IR) based on the M

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Crossref
Publication Date
Tue Nov 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Proposal of Using Principle of Maximizing Entropy of Generalized Gamma Distribution to Estimate the Survival probabilities of the Population in Iraq
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In this research we been estimated the survival function for data suffer from the disturbances and confusion of Iraq Household Socio-Economic Survey: IHSES II 2012 , to data from a five-year age groups follow the distribution of the Generalized Gamma: GG. It had been used two methods for the purposes of estimating and fitting which is the way the Principle of Maximizing Entropy: POME, and method of booting to nonparametric smoothing function for Kernel, to overcome the mathematical problems plaguing integrals contained in this distribution in particular of the integration of the incomplete gamma function, along with the use of traditional way in which is the Maximum Likelihood: ML. Where the comparison on the basis of the method of the Cen

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Crossref
Publication Date
Sun Nov 19 2017
Journal Name
Iraqi Journal Of Laser
Sulfur Hexafluoride (SF6) Trace Gas Sensing using Modulated CO2 Laser Beam
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Photonic Crystal Fiber Interferometers (PCFIs) are widely used for sensing applications. This work presents the fabrication and the characterization of a relative humidity sensor based on a polymer-coated photonic crystal fiber that operates in a Mach- Zehnder Interferometer (MZI) transmission mode. The fabrication of the sensor involved splicing a short (1 cm) length of Photonic Crystal Fiber (PCF) between two single-mode fibers (SMF). It was then coated with a layer of agarose solution. Experimental results showed that a high humidity sensitivity of 29.37 pm/%RH was achieved within a measurement range of 27–95%RH. The sensor also showed good repeatability, small size, measurement accuracy and wide humidity range. The RH sensitivity o

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Publication Date
Wed Jan 01 2025
Journal Name
Socar Proceedings
Enhanced permeability estimation in non-cored wells using a modified flow zone index-permeability crossplot: a case study of carbonate reservoirs
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The permeability estimates for the uncored wells and a porosity function adopting a modified flow zone index-permeability crossplot are given in this work. The issues with implementing that approach were mostly crossplots, due to the influence of geological heterogeneity, did not show a clear connection (scatter data). Carbonate reservoir flow units may now be identified and characterized using a new approach, which has been formally confirmed. Due to the comparable distribution and flow of clastic and carbonate rock fluids, this zoning method is most effective for reservoirs with significant primary and secondary porosity. The equations and correlations here are more generalizable since they connect these variables by combining cor

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Scopus Clarivate Crossref
Publication Date
Tue May 01 2012
Journal Name
Engineering Analysis With Boundary Elements
Radial integration boundary integral and integro-differential equation methods for two-dimensional heat conduction problems with variable coefficients
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Publication Date
Mon Sep 01 2025
Journal Name
International Communications In Heat And Mass Transfer
Boosting energy storage and recovery in shell-and-multitube latent heat storage systems through sunburst-distributed radial fins
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Scopus (4)
Crossref (4)
Scopus Crossref
Publication Date
Sun Jun 01 2025
Journal Name
Case Studies In Thermal Engineering
Accelerated discharging kinetics in zigzag- shaped triplex-tube latent heat storage with nano-modified phase change materials additives
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Scopus (10)
Crossref (11)
Scopus Crossref
Publication Date
Sun May 02 2021
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Application of banking institutions' governance variables and their impact on financial performance as measured by (ROA & ROE): an applied study on a sample of local Islamic banks listed on the Iraq Stock Exchange
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The research seeks to achieve its goal of demonstrating the impact of applying banking governance variables on the financial performance of Islamic banks, and the independent research variables are represented by (X) by (the number of independent members in the board (X1), the number of directors in the board (X2), the number of committees emanating from the board ( X3), the percentage of shares owned by major shareholders in the board (X4), the number of members of the Sharia supervisory board (X5)), and the dependent variable (Y) is represented by (rate of return on assets (Y1), rate of return on equity (Y2)).

The research sample included (4) Islamic banks, namely (Iraqi Islamic Bank, National Islamic Bank, Jihan Islamic Bank,

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