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Some Thermodynmic Properties of binary Mixtures of Alcohol isomers and Sulfolane at 298.15K
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The refractive indices, nD densities 𝜌, and viscosities  of binary mixtures of sulfolane + n -butanol + sec- butanol + iso- butanol + tert – butanol + n-propanol and iso- propanol were measured at 298.15K. Form experimental data, excess molar volum VE , excess molar refractivity ∆nD, excess molar viscosity  E and excess molar Gibbs free energy of activation of viscous flow G *E were calculated. From n-propanol – sulfolane and iso- propanol sulfolane mixtures showed negative ∆nD, n-butanol – sulfolane, sec-butanal – sulfolane, iso-butanol – sulfolane and tert- butanol sulfolane , nD was positive over the whole mole fraction rang , while VE ,  E and G *E show a negative deviation. The results obtained for binary mixtures suggest two types of molecular interaction. One is the formation of new stable complexes between the sulfone group of sulfolane and the hydroxyl group of alcohols and the second is related to the participation in destroying the mixture structure and forming a new structure. Excess molar quantities of these binary mixtures were found to be affected directly by the position of hydroxyl group and the steric associated with the methyl group.

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Publication Date
Wed Apr 19 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Effect of Doping by Sr on the Structural, Mechanical and Electrical Characterization of La1Ba1-xSrx Ca2Cu4O8.5+δ
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       The Sr doped La1Ba1-xSrx Ca2Cu4O8.5+δ samples with 0 ≤ x ≤ 0.3 had been prepared using the solid state reaction. The samples were claimed at 800°C for 3hr, palletized and sintered at 860°C for 20hr in air . Dielectric constant and loss by means of capacitance have been investigated with frequencies in the range of 1kHZ to 1MHZ for our samples at room temperature. Also, Shore hardness has been measured. The dielectric constant and loss decrease slightly with the increase of frequency for all compounds. Additionally, the partial substitution of Sr+2 into Ba+2 sites never have effect on the dielectric properties. X-ray diffraction (XRD) analysis showed a tetragonal structure and the

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Publication Date
Tue Jan 08 2019
Journal Name
Iraqi Journal Of Physics
Preparation and characterization of mixed SnO2:CdO thin films as gas sensor
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In this study, tin oxide (SnO2) and mixed with cadmium oxide (CdO) with concentration ratio of (5, 10, 15, 20)% films were deposited by spray pyrolysis technique onto glass substrates at 300ºC temperature. The structure of the SnO2:CdO mixed films have polycrystalline structure with (110) and (101) preferential orientations. Atomic force microscopy (AFM) show the films are displayed granular structure. It was found that the grain size increases with increasing of mixed concentration ratio. The transmittance in visible and NIR region was estimated for SnO2:CdO mixed films. Direct optical band gap was estimated for SnO2 and SnO2 mixed CdO and show a decrease in the energy gap with increasing mixing ratio. From Hall measurement, it was fou

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Publication Date
Sat Jan 20 2024
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Isolation and Identification of Endophytic Fungi from Aloe vera Leaves and Chemical Analysis of the Alcoholic Extract of the Leaves Using HPLC, GC, and GC-Mass Devices
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The study's goals were to separate and identify endophytic fungi from Aloe vera leaves by looking at their morphology and molecules, as well as to find the chemical compounds in the leaf extract by using HPLC, GC, and GC-Mass instruments. The results showed that 53 endophytic fungi were isolated from a total of 120 pieces of A. vera leaves, with a total colonization rate of 44.16%. The fungus Aspergillus terreus had a colonization rate of 14.16%; Aspergillus niger had a colonization rate of 13.33%; Penicillium chermesinum demonstrated a colonization rate of 6.66%; Paecilomyces variotii had a colonization rate of 2.5%; Talaromyces radicus; and Aspergillus flavus achie

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Publication Date
Fri Jul 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
The vocational Adjustment of workers according to the analysis of job and design ((Local Research in the technology al information and communication office in the parliament))
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Abstract

The purpose of the present paper is to light on the relationship between jobs design, analysis and its reflections on reinforcing workers' vocational adjustment. The present paper aims to accomplish cognitive and applied goals, top of which, test of functional analysis ability to have effect upon workers' vocational adjustment via job design directly and indirectly owning to the virtual factor practiced by these practices on the sought organization. The problem of the present paper comes with many, the most important is the of how to bolster and back up worker's technical adjustment through good and accurate design for the job.

Based on this problem and goals as to expla

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Publication Date
Sat Jan 13 2018
Journal Name
Journal Of Engineering
Pitting Corrosion Behavior of 304 SS and 316 SS Alloys in Aqueous Chloride and Bromide Solutions
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The importance of the present work falls on the pitting corrosion behavior investigation of 304 SS and 316 SS alloys in 3.5 wt%  of aqueous solution bearing with chloride and bromide anion  at different solutions temperature range starting from (20-50)oC due to the pitting corrosion tremendous effect on the economic, safety and materials loss due to leakage. The impact of solution temperatures on the pitting corrosion resistance at 3.5wt% (NaCl and  NaBr) solutions for the 304 SS and 316 SS has been investigated utilizing the cyclic polarization techniques at the potential range -400 to1000 mV vs. SCE at 40 mV/sec scan rate followed by the surface characterization employing Scanning Electron&nbs

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Publication Date
Wed Feb 01 2023
Journal Name
Baghdad Science Journal
Accumulation of Heavy Metals in Agricultural Crops and Ecological Series of Crops Placement
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The accumulation of toxic elements in vegetables and melons grown in agriculture, Brassica rapa - turnip, Solanum lycopersicum - tomato, Citrullus lanatus - watermelon, Capsicum annuum - bell pepper, Daucus carota - carrots, Cucurbita pepo - pumpkin, Cucumis melo - melon, and also Prunus armeniaca - apricot from fruit trees were analyzed. The excess of maximum allowable concentrations in agricultural crops of the element As by 1.65-1.75, Cd - 1.6-2.3, Cr -1.2-2.35, Cu -1.6-3.3, Ni - 1.16-3.53, Pb - 1.54-3.08, Al - 1.36-3.5, Sb - 2.0-33, Se - 1.1-3.3 times was established. The maximum allowable concentration of mercury in vegetables and melons was equal to 0.02 mg/kg,

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Publication Date
Wed Jul 01 2015
Journal Name
Journal Of Educational And Psychological Researches
Reality and constraints of the use of computers in public schools in the governorate of Ma'an From the standpoint of teachers
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 This study aims to recognize the process of using computer in    publicschools in Ma`an governorate in terms of hardware, capabilities, and teachers usage. It also aims to identify the most important obstacles those schools face from a teachers perspective.

            The study sample consists of (150) teachers from different disciplines. The researcher prepared two questionnaires related to the research pivotal, then presented to a group of arbitrators to be used in this final form. The data was analyzed statistically and the study concluded that there is a shortage in the computer services provided to teachers, and there is a w

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Publication Date
Thu Jun 30 2016
Journal Name
European Journal Of Chemistry
Reaction paths and transition states of the C-C and C-H bond cleavage in the aromatic anthracene and phenanthrene molecules
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The reaction paths of the C-C and C-H bond cleavage in the anthracene and phenanthrene aromatic molecules are studied by applying the ab-initio DFT method. It is found that the C-C bond cleavage proceeds via a singlet aromatic transition state, compelled through a disrotatoric ring opening reaction. A suprafacial H atom shift follows the transition state, leading to the formation of a methylene -CH2 and an acetylenic or allenic moiety. The calculated activation energies for anthracene range from 158.81-208.90 kcal/mol and the reaction energies from 96.106-156.976 kcal/mol. For phenanthrene, the energy values are 157.39-202.34 kcal/mol and 62.639-182.423 kcal/mol, respectively. For the C-H cleavage reactions, the calculated reaction energies

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Publication Date
Sat Jan 20 2024
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
An Assessment of Glutathione-S-Transferase and Lipid Profile in Obese Iraqi Patients
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Obesity is a chronic disease that may have genetic, environmental, and other causes. Obesity is a shortcut to many diseases, such as hypertension, diabetes, atherosclerosis, and other chronic diseases. Oxidative stress increases obesity through free radicals. Glutathione S-transferase (GST) is a metabolic enzyme used to remove toxins. This study aimed to determine GST activity in obese patients as a predictor of oxidative stress and the effectiveness of lipid profiling in obese patients. The study included 139 samples of obese and healthy people (obese group 84 and healthy group 55). Both groups (obese and healthy groups) were divided into four groups based on body mass index. Blood samples were collected from obese males and females in

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Publication Date
Sun Jun 01 2008
Journal Name
Baghdad Science Journal
Effect of physical form and washing of treated and untreated rice straw with sodium hydroxide upon chemical composition and in vitro digestibility
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Hydroxide upon the chemical composition and dry matter(DM) and organic matter(OM) digestibility . Rice straw was treated with 4% sodium hydroxide using 30% of DM basis moisture, and incubated at 40 ºC for 40 days., DM digestibility (DMD) was significantly affected (P<0.01) by the treatment , where DMD increased The objective of this experiment was to study the effect of physical form (long ,chopped and ground ) and washing rice straw treated with sodium from 42.32 to 45.41% , OM digestibility (OMD) and total digestible nutrient (TDN) increased(P<0.05) from 47.38 and 49.33 to 49.67 and 52.83% ,respectively. While hemicellulose content increased (P<0.05 ) from 261.71 to 268.17 gm/kg DM ,and metabolizable energy (ME) from 7.11 to 7.48 MJ/

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