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Decomposition of selected chlorinated volatile organic compounds by ceria (CeO 2)
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Chlorinated volatile organic compounds (CVOCs) are toxic chemical entities emitted invariably from stationary thermal operations when a trace of chlorine is present. Replacing the high-temperature destruction operations of these compounds with catalytic oxidation has led to the formulation of various potent metal oxides catalysts; among them are ceria-based materials. Guided by recent experimental measurements, this study theoretically investigates the initial steps operating in the interactions of ceria surface CeO2(111) with three CVOC model compounds, namely chloroethene (CE), chloroethane (CA) and chlorobenzene (CB). We find that, the CeO2(111) surface mediates fission of the carbon–chlorine bonds in the CE, CA and CB molecules via modest reaction barriers. As a result of localization of excess electrons left behind after creation of oxygen vacancies, analogous fission over an oxygen vacant surface systematically necessitates lower energy barriers. Dehydrochlorination of CE and CA molecules preferentially proceeds via a dissociative addition route; however, subsequent desorption of vinyl and ethyl moieties requires less energy than surface assisted β C–H bond breakage. The profound stability of hydrocarbon species on the surface contributes to the observed deactivation of ceria at temperatures as low as 580 K under pyrolytic conditions. Adsorption of an oxygen molecule at an oxygen vacant site initiates decomposition of the adsorbed phenyl moiety. Likewise, adsorbed surface hydroxyl groups serve as the hydrogen source in the observed conversion of CB into benzene. A plausible mechanism for the formation of 1,4-dichlorobenzene incorporates abstraction of a para hydrogen in the CB molecule by an O− surface anion followed by chlorine transfer from the surface. Plotted conversion–temperature profiles via a simplified kinetic model against corresponding experimental profiles exhibit a reasonable agreement. The results from this study could be useful in the ongoing efforts to improve ceria's catalytic capacity for destroying CVOCs.

Publication Date
Wed Jul 31 2019
Journal Name
Journal Of Educational And Psychological Researches
An Instructional Design According to the constructivism Model for Chemistry Subject and Its Effect on the Life Skill by the Second Intermediate Female Students
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The research aims to identify the effect of teaching-learning design based on the constructivism theory on the life skills of middle stage students. The sample consisted of (60) students from one of the middle schools in Baghdad's governorate. The experimental group and control group consisted of 30 students for each group, the research tool was the life skills scale composed of (78) items. The scale proved its validity and reliability, which was found to be (0.85). The results showed a statistically significant difference in life skills between the two groups of research in favor of the experimental group, which studied the educational design according to models of constructivism theory compared to the usual method of teaching.

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Publication Date
Wed Sep 29 2021
Journal Name
College Of Islamic Sciences
The attitude of Imam Ibn Jarir al-Tabari to the occurrence of unanimous and its convening by statement of the majority in light of his interpretation - Jami` al-Bayan on the interpretation of the verse of the Qur’an -‘‘Applied Models’’
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The research deals with the statement of the importance of unanimous in Islamic Sharia in terms of being the third source of Islamic legislation after the Holy Qur’an and the Sunnah of the Prophet, and the extent of interest of the scholars of interpretation in it, and those who took great interest in mentioning what was agreed upon in every site that necessitated mentioning its issues within, or mentioning an event that has encountered an unanimous, and in various sciences, to extract and extrapolate Sharia rules when these rules are lost in the texts, because it is based on them and derived from them. Among these distinguished scholars is Muhammad bin Jarir al-Tabari. Besides, the research discusses in

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Publication Date
Mon Mar 13 2017
Journal Name
Journal Of Baghdad College Of Dentistry
A study to compare the internal fitness and marginal gap between single crowns and crowns within three-unite bridge of zirconia substructure fabricated by CAD-CAM system. (An In vitro study)
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ABSTRACT Purpose: the aim of this in vitro study was to compare the marginal gap and internal fitness between single crowns and the crowns within three-unit bridges of zirconium fabricated by CAD-CAM system. Materials and methods: A standard model from ivoclar company was used as a pattern to simulate three-units bridge (upper first molar and upper first premolar) as abutments used to fabricate stone models, eight single crowns for premolar and eight of three units bridges. Crowns and bridges fabricated by CAD-CAM system were cemented on their respective stone models then sectioned at the mid-point buccolingaully and misiodistaly and examined under stereomicroscope. Result: the marginal gap in premolar crowns and premolar within bridge we

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Publication Date
Fri Dec 01 2023
Journal Name
Case Studies In Chemical And Environmental Engineering
Removal of copper from a simulated wastewater by electromembrane extraction technique using a novel electrolytic cell provided with a flat polypropylene membrane infused with 1-octanol and DEHP as a carrier
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Publication Date
Sun Nov 23 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Hard palate bone density and thickness determination using CT scan and their relationships with body compositions measured by bioelectrical impedance analysis for Iraqi adult sample
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Background: This study was conducted to evaluate the hard palate bone density and thickness during 3rd and 4th decades and their relationships with body mass index (BMI) and compositions, to allow more accurate mini-implant placement. Materials and method: Computed tomographic (CT) images were obtained for 60 patients (30 males and 30 females) with age range 20-39 years. The hard palate bone density and thickness were measured at 20 sites at the intersection of five anterioposterior and four mediolateral reference lines with 6 and 3 mm intervals from incisive foramen and mid-palatal suture respectively. Diagnostic scale operates according to the bioelectric impedance analysis principle was used to measure body weight; percentages of body fa

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Publication Date
Tue Jun 01 2021
Journal Name
Journal Of The College Of Languages (jcl)
Metaphor in Political Discourse Press Articles By Louis Bassets As A Model: La metáfora en el discurso político. Los artículos de Lluís Bassets como ejemplo
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       The present paper focuses on studying a rhetorical form often used in Spanish linguistic discourse .It also examines the study two sides (theoretical and practical), the concept of metaphor, the most important modern school that deals with this issue, the development of this technique and its relationship with other intellectual ideologies, and the role metaphor plays in interpreting the meaning of the linguistic discourse especially in conveying political message. The study allows the formulation and the creation of a conceptual picture for the purposes of metaphor in the linguistic discourse used in Spanish press. It investigates discursive models from the Spanish press,

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Publication Date
Wed Jun 01 2022
Journal Name
Journal Of The College Of Languages (jcl)
The Linguistic Characteristics In The Morphology ( Nominal Suffixes ) Of a Number Of ( Khoryat or Hoyrat ) Printed By The Poet Kamal Mustafa Daquqli: Kemal Mustafa Dakuk ̕ lunun Basılmayan Bazı Hoyratlarında Şekil Bilgisi Özelliklerin ( İsim Durum Ekleri )
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The present study, entitled “ linguistic characteristics (the morphology - nominal suffixes ) of a number of (Quriyat or koyrat ) by the poet Kamal Mustafa Daquqli, aims at studying and making a comparison between  Turkmen dialect written and spoken forms that show many of the hidden language structures. Similarly, the study sheds light on the poet as one of the most prominent literary figures in Turkmenistan literature.

Turkman Quriyat is one of Turkman blank verse significant forms. Apart from (songs and Quriyat) and until the 19th C., folk poetry has been stalled for a long time but reclaimed its literary high position in the middle of the 20th C.

The study introduction briefly discusses Tu

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Publication Date
Fri Oct 01 2010
Journal Name
Analytica Chimica Acta
A reversed phase high performance liquid chromatography method for the determination of fumonisins B1 and B2 in food and feed using monolithic column and positive confirmation by liquid chromatography/tandem mass spectrometry
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The development of a reversed phase high performance liquid chromatography fluorescence method for the determination of the mycotoxins fumonisin B1 and fumonisin B2 by using silica-based monolithic column is described. The samples were first extracted using acetonitrile:water (50:50, v/v) and purified by using a C18 solid phase extraction-based clean-up column. Then, pre-column derivatization for the analyte using ortho-phthaldialdehyde in the presence of 2-mercaptoethanol was carried out. The developed method involved optimization of mobile phase composition using methanol and phosphate buffer, injection volume, temperature and flow rate. The liquid chromatographic separation was performed using a reversed phase Chromolith® RP-18e column

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Publication Date
Thu Apr 06 2023
Journal Name
Materials Science Forum
Study of the Effect of Ce <sup>3+</sup> on the Gas Sensitivity and Magnetic Properties of Cu<sub>x</sub>Ce<sub>0.3-X</sub>Ni<sub>0.7</sub>Fe<sub>2</sub>O<sub>4</sub> Ferrite Nanoparticles
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This study includes the preparation of the ferrite nanoparticles CuxCe0.3-XNi0.7Fe2O4 (where: x = 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3) using the sol-gel (auto combustion) method, and citric acid was used as a fuel for combustion. The results of the tests conducted by X-ray diffraction (XRD), emitting-field scanning electron microscopy (FE-SEM), energy-dispersive X-ray analyzer (EDX), and Vibration Sample Magnetic Device (VSM) showed that the compound has a face-centered cubic structure, and the lattice constant is increased with increasing Cu ion. On the other hand, the compound has apparent porosity and spherical particles, and t

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Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Economics And Administrative Sciences
The impact of enabling the effectiveness of the work of the audit committees in private commercial banks (A survey study of the views of a sample of the objective of the inspection bodies represented by the Central Bank and the Securities Commission and e
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The aim of this study is to identify the effect of enabling the effectiveness of the work of the audit committees in private commercial banks and to identify the extent of awareness of the importance of empowerment in the work of these committees, especially as it is known that these committees, especially the inspection committees that go to private banks and from various sources including committees of the Central Bank of Iraq Committees of the Securities Commission and finally committees of the external audit offices, through an analysis of the determinants of empowerment in the performance of the most important work of the audit committees, namely: supervising the process of preparing reports, supervising the system of intern

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