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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
compared with the others, but this equation is sometimes not very preferable. It was
noted that SRK equation was the closest one in its accuracy to that of the Lee-Kesler
equation in calculating the residual entropy SR of superheated vapor, but it was
developed primarily for calculating vapor-liquid equilibrium and to overcome this
problem, efforts were directed toward the possibility of modifying SRK equation to
increase its accuracy in predicting the residual entropy as much as possible. The
modification was made by redefining the parameter α in SRK equation to be a
function of reduced pressure, acentric factor, and polarity factor for polar compounds
in addition to be originally function of reduced temperature and n parameter –which is
also function of acentric factor– by using statistical methods. This correlation is as
follows:

α =[1+n(γ)]2  , γ=-0.920338Pr-0.34091 +0.064049Tr4 ω +0.370002ω-Pr0.996932 Tr-4x
This new modified correlation decreases the deviations in the results obtained by
using SRK equation in calculating SR when comparing with the experimental data.
The AAD for 2791 experimental data points of 20 pure compounds is 4.3084 J/mol.K
while it becomes 2.4621 J/mol.K after modification. Thus SRK equation after this
modification gives more accurate results for residual entropy of superheated vapor of
pure 20 compounds than the rest of the equations mentioned above.

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Publication Date
Mon Sep 30 2013
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Synthesis, Characterization and Evaluation of Overbased Magnesium Fatty Acids Detergent for Medium Lubricating Oil
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A series of overbased magnesium fatty acids such as caprylate, caprate, laurate, myristate, palmitate, stearate and oleate) were synthesized by the reaction of the fatty acids with active – 60 magnesium oxide and carbon dioxide (CO2) gas at 60 oC in the presence of ammonia solution as catalyst, toluene / ethanol solvent mixture (9:1vol/vol) was added.
The prepared detergent additives were characterized by FTIR, 1HNMR and evaluated by blending each additive in various concentrations with medium lubricant oil fraction (60 stock) supplied by Iraqi Midland Refineries Company. The total base number (TBN, mg of KOH/g) was determined, and the results of TBN were treated by using two-way analysis of variance (ANOVA) test. It was found that

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Publication Date
Tue Aug 01 2023
Journal Name
Journal Of Engineering
Comparative Analysis of H2 and H∞ Robust Control Design Approaches for Dynamic Control Systems
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This paper discusses using H2 and H∞ robust control approaches for designing control systems. These approaches are applied to elementary control system designs, and their respective implementation and pros and cons are introduced. The H∞ control synthesis mainly enforces closed-loop stability, covering some physical constraints and limitations. While noise rejection and disturbance attenuation are more naturally expressed in performance optimization, which can represent the H2 control synthesis problem. The paper also applies these two methodologies to multi-plant systems to study the stability and performance of the designed controllers. Simulation results show that the H2 controller tracks a desirable cl

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Publication Date
Mon Oct 22 2018
Journal Name
Journal Of Economics And Administrative Sciences
The use of water resources internationally and their implications for the water issue globally
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The rivers are the main source of fresh water for many countries and the great development which is considered as one of the sustainable development elements in its various agricultural, industrial, domestic and environmental fields .The countries of the world seek food security and water security in order to ensure the basic needs of citizens .Because their distribution is uneven in many regions of the world with different human needs, which leads to conflicts over water sources, especially those located in one international river basin .This has led to the emergence of internationallegal rules governing the management of The problem revolves around the dialectic between limited water resources and increased need for water use b

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Publication Date
Thu May 28 2020
Journal Name
Iraqi Journal Of Science
Palynofacies and Source Rocks Evaluation for Selected Samples of Subba Oil Field, Southern Iraq
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This study includes a palynological and organic geochemical evaluation of Nahr Umr, Zubair, and Yamama Formations in the Subba field, Southern Iraq, represented by three wells (Su-14, Su-9 and Su-8). The determination of quantity organic matter showed that the rocks of Nahr Umr Formation had a total organic carbon of 4.76%, indicating very good production of hydrocarbons where type (II) kerogen was dominant, but the rocks were thermally immature. Zubair Formation had a total organic carbon of 1.91% to 2.26%, indicating good to very good production of hydrocarbons where kerogen of types (I) and (II/III) were dominant, with low thermal maturity. Yamama Formation showed a total organic carbon of 1.68%, revealing good production of hydrocarb

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Publication Date
Wed Feb 20 2019
Journal Name
Iraqi Journal Of Physics
Theoretical spectroscopic studies of potential energy curves and Fortran parabola for beryllium oxide molecule
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    Theoretical spectroscopic  studies of  beryllium oxide has been  carried out, potential energy curves for ground states X1Σ+ and exited states A1Π , B1Σ+ by using two functions Morse and  and Varshni compared with experimental results. The potentials of this molecule are agreement with experimental results. The Fortrat Parabola corrcponding to  and branches were determind in the range 1<J<20 for the (0-0) band. It was found that for electronic transition  A1Π- X1Σ+  the bands head lies in  branche of  Fortrat p

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Publication Date
Wed Aug 31 2022
Journal Name
Al-kindy College Medical Journal
A comparison of cross sections for Selenium -73 radioisotopes produced by accelerators and reactors
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Background: Selenium-73 with half- life of 7.15 hour emits β+ in nature and has six stable isotopes which are ( 74Se,76Se,77Se,78Se,80Se and 82Se ). Selenium-73 has many applications in technology and radioselenium compounds of metallic have found various applications in medicine.

Objective:  To make a comparison between different reactions that produced cross sections of Se-73 radioisotopes.

Subjects and methods: The feasibility of the production of Selenium -73 via various nuclear reactions was investigated. Excitation functions of 73Se production by the re

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Publication Date
Sun Jun 07 2009
Journal Name
Baghdad Science Journal
A New Spectrophotometric Method for Analysis of Allopurinol in Aqueous Solutions and Pharmaceutical Preparations
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A new method for determination of allopurinol in microgram level depending on its ability to reduce the yellow absorption spectrum of (I-3) at maximum wavelength ( ?max 350nm) . The optimum conditions such as "concentration of reactant materials , time of sitting and order of addition were studied to get a high sensitivity ( ? = 27229 l.mole-1.cm-1) sandal sensitivity : 0.0053 µg cm-2 ,with wide range of calibration curve ( 1 – 9 µg.ml-1 ) good stability (more then24 hr.) and repeatability ( RSD % : 2.1 -2.6 % ) , the Recovery % : ( 98.17 – 100.5 % ) , the Erel % ( 0.50 -1.83 % ) and the interference's of Xanthine , Cystein , Creatinine , Urea and the Glucose in 20 , 40 , 60 fold of analyate were also studied .

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Publication Date
Sun Oct 22 2023
Journal Name
Iraqi Journal Of Science
Synthesis, Characterization and Evaluation of Antimicrobial Activity for New Heterocyclic Derivatives Containing Pentagonal, HexagonalRings.
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This research, involved a series of some new compounds containing different hetero cyclic new pentagonal and hexagonal rings, through the reaction of 2-mercapto-3-phenyl-4(3H)quinazolinone (1) with chloroacetylchloride in the presence of potassium hydroxide, and dry dimethylformamide (DMF) as a solvent to obtain the intermediate compound (2). This compound is reacted with different reagents to give four routes, the first route include direct reaction with substituted-2-aminobenzothiazole under certain conditions to give new compounds (3-9). The second route involved condensation compound (2) with 5-substituted-2-amino-1,3,4-oxadiazole in the presence of potassium carbonate anhydrous to give new compounds (10-13).while the third route inv

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Publication Date
Fri Jan 01 2016
Journal Name
Diabetic Foot &amp; Ankle
Risk factors for occurrence and recurrence of diabetic foot ulcers among Iraqi diabetic patients
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There are a few studies that discuss the medical causes for diabetic foot (DF) ulcerations in Iraq, one of them in Wasit province. The aim of our study was to analyze the medical, therapeutic, and patient risk factors for developing DF ulcerations among diabetic patients in Baghdad, Iraq.

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Publication Date
Wed Nov 27 2019
Journal Name
Environmental Science And Pollution Research
Application of emulsion and Pickering emulsion liquid membrane technique for wastewater treatment: an overview
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