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Performance Evaluation of Three Phase Spray Direct Contact Heat Exchanger
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The present investigation deals with experimental study of three-phase direct-contact heat exchanger, for water-Freon R11 system, where water is the continuous phase (liquid) and Freon R11 (liquid-gas) is the dispersed phase. The test section consisted of a cylindrical Perspex column with inner diameter 8cm and 1.2m long, in which, water was to be confined. Liquid Freon R11 drops were injected into the hot water filled column, through a special design of distributors at the bottom of the column. The liquid Freon R11 drops rose on their way up and evaporated into two-phase bubbles at atmospheric pressure. The study was devoted to express the effect of process variables such as column height, Freon R11 mass flow rate and initial temperature of water on the average percentage holdup, heat transfer rate, volumetric heat transfer coefficient and effectiveness.

The obtained experimental results showed that the average percentage holdup increased with increasing in the process variables. The heat transfer rate increased clearly with increasing in mass flow rate of Freon R11 while it increased very little when column height and initial temperature of water increased, it increased two times when increase the mass flow rate from 1.8 to 5.4 kg/hr. The volumetric heat transfer coefficient was found to decrease with increasing in column height and initial temperature of water, while it was increased with increasing in mass flow rate of Freon R11. The effectiveness was found to increase (maximum 90%) with increasing in column height and decreasing in the mass flow rate of Freon R11 and initial temperature of water. A statistical analysis was performed to get general correlations for the average percentage holdup, heat transfer rate, volumetric heat transfer coefficient and effectiveness as a function of the studied parameters.

 

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Publication Date
Sun Sep 07 2014
Journal Name
Baghdad Science Journal
Optimum conditions for ascorbic acid determination in three Iraqi citrus using HPLC technique
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A high-performance liquid chromatography method was employed for the quantitative determination of ascorbic acid (AA) which called vitamin C in three types of Iraqi citrus (orange mandarin and aurantium ) and to establish this goal , evaluation of ascorbic acid degradation is so important due to its significant criticality when exposure to ordinary atmospheric conditions. The chromatographic analysis of AA was carried out after their sequential elution with KH2PO4 ( as mobile phase) by reverse-phase HPLC technique with C8 column and UV detection at 214 nm. .Bad resolutions was appeared clearly for C8 column , so another alternative condition were carried out to improve the resolution by replacement of C8 by C18 column .Statistical treat

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Publication Date
Sun Sep 06 2015
Journal Name
Baghdad Science Journal
A New Three Step Iterative Method without Second Derivative for Solving Nonlinear Equations
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In this paper , an efficient new procedure is proposed to modify third –order iterative method obtained by Rostom and Fuad [Saeed. R. K. and Khthr. F.W. New third –order iterative method for solving nonlinear equations. J. Appl. Sci .7(2011): 916-921] , using three steps based on Newton equation , finite difference method and linear interpolation. Analysis of convergence is given to show the efficiency and the performance of the new method for solving nonlinear equations. The efficiency of the new method is demonstrated by numerical examples.

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Publication Date
Tue Oct 27 2020
Journal Name
Proceedings Of The 2020 2nd International Conference On Sustainable Manufacturing, Materials And Technologies
The complex dynamic in three species food webmodel involving stage structure and cannibalism
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A three species food web model involving a stage structure and cannibalism in the top predator species is proposed and studied. It is assumed that the prey species growth logistically in the absence of predator and the predation process occurred according to theLotka-Volterra functional response. The existence, uniqueness and bounded-ness of the solution of the model are investigated. The local and global stability conditions of all possible equilibrium points are established.The persistence conditions of the model are also determined. The local bifurcation near each of the equilibrium points is analyzed. The global dynamics of the model is investigated numerically and compared with the obtained analytical results. It is observed that the p

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Publication Date
Tue Jan 01 2013
Journal Name
International Journal Of Contemporary Mathematical Sciences
Equivalent between the Criterion and the Three Open Set's Conditions in Disk-Cyclicity
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A vector in a separable infinite dimensional Hilbert space is called disk-cyclic for bounded operator if the orbit α : 0, α∈;|∝| 1is dense in. The useful tool used to discover codisk-cyclic operation is called the disk-cyclic Criterion. In this paper we will show that some equivalent conditions of the

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Publication Date
Sun Jun 20 2021
Journal Name
Baghdad Science Journal
Wireless Propagation Multipaths using Spectral Clustering and Three-Constraint Affinity Matrix Spectral Clustering
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This study focused on spectral clustering (SC) and three-constraint affinity matrix spectral clustering (3CAM-SC) to determine the number of clusters and the membership of the clusters of the COST 2100 channel model (C2CM) multipath dataset simultaneously. Various multipath clustering approaches solve only the number of clusters without taking into consideration the membership of clusters. The problem of giving only the number of clusters is that there is no assurance that the membership of the multipath clusters is accurate even though the number of clusters is correct. SC and 3CAM-SC aimed to solve this problem by determining the membership of the clusters. The cluster and the cluster count were then computed through the cluster-wise J

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Publication Date
Fri Jul 01 2016
Journal Name
Infection And Immunity
The Periodontal Pathogen Porphyromonas gingivalis Preferentially Interacts with Oral Epithelial Cells in S Phase of the Cell Cycle
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ABSTRACT<p> <named-content content-type="genus-species">Porphyromonas gingivalis</named-content> , a key periodontal pathogen, is capable of invading a variety of cells, including oral keratinocytes, by exploiting host cell receptors, including alpha-5 beta-1 (α5β1) integrin. Previous studies have shown that <named-content content-type="genus-species">P. gingivalis</named-content> accelerates the cell cycle and prevents apoptosis of host cells, but it is not known whether the cell cycle phases influence bacterium-cell interactions. The cell cycle distribution of oral keratinocytes was characterized by flow cytometry and BrdU (5-bro</p> ... Show More
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Publication Date
Mon Jun 05 2023
Journal Name
Al-khwarizmi Engineering Journal
Extraction of Bovine Serum Albumin by Aqueous Two-Phase System Using PEG4000/Sodium Citrate and PEG8000/Sodium Phosphate
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Aqueous Two Phase System (ATPS) or liquid-liquid extraction is used in biotechnology to recover valuable compounds from raw sources. In Aqueous Two-Phase Systems, many factors influence the Partition coefficient, K, (which is the ratio of protein concentration in the top phase to that in the bottom phase) and the Recovery percentage (Rec%). In this research, two systems of ATPS were used: first, polyethylene glycol (PEG) 4000/Sodium citrate (SC), and the second, PEG8000/ Sodium phosphate (SPH), for the extraction of Bovine Serum Albumin (BSA). The behavior of Rec% and K of pure (BSA) in ATPS has been investigated throughout the study by the effects of five parameters: temperature, concentration of polyethylene glycol (P

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Publication Date
Fri Jun 19 2026
Journal Name
Journal Of Baghdad College Of Dentistry
The Effect of LED Light on Depth of Cure and Microhardness of Three Types of Bulkfill Composite
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Background: To evaluate the ISO depth of cure of bulkfill composites and depth of cure which determined by Vickers microhardness test. Materials and Methods: Bulkfill resin composite specimens (n=150) were prepared of three bulkfill composite materials (TetricEvo Ceram, Quixfil and SDR) and light cured by Flash max p3 for 3, 10, 20 seconds and by wood pecker for 10, 20 seconds respectively, a mold was filled with one of the three bulkfill composites and light cured. The specimens removed from the mold and scraped by plastic spatula and the remaining length (absolute length) was measured which represent the ISO depth of cure. After that the specimens were returned into the mold and a microhardness indentation device applied on the specimen

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Publication Date
Thu Jun 27 2024
Journal Name
Journal Of Optics
The influence of surfactant type on the formation of zinc oxide nanoparticles via liquid phase pulsed laser ablation technique
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To produce Zinc Oxide NanoParticles, ZnO-NPs, different methods can be used. However, the utilization of Liquid-Phase Pulsed Laser Ablation, LP-PLA, methodology of three distinct environment of aqueous using pure zinc plate will be one of the approaches for this job. Thus, in this work, concentrates on the influence of the results after employing some changes on the environment in other words, the influence of the NPs size and/or the NPs availability/appearance. Cetyltrimethylammonium Bromide, CTAB, is one of the three surfactants that have been used in the water-based solution. That is, the Sodium Dodecyl Sulfate, SDS, besides the Distilled Water, DW, the three surfactants will be ready when the molarity of the DW is around 10− 3 M. Th

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Publication Date
Tue Nov 01 2016
Journal Name
Journal Of Cosmetics, Dermatological Sciences And Applications
Direct transplant of melanocytes from normal donor area into vitiligenous recipient area by intralesional injection of melanocytes using spade like needle technique
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KE Sharquie, AA Noaimi, ZN Al-Khafaji…, Journal of Cosmetics, Dermatological Sciences and Applications, 2016 - Cited by 2

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