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.
The term "semantic exchange" was popularized in Arabic, especially in derivatives, grammatical structures, etc., but it came under different names or terms, including deviation, deviation, transition, displacement, tooth breach, replacement, attention, etc. In the rooting of this term through its study in language and terminology, and among linguists, grammar and others, we have reached a number of results, including The existence of a harmonization between the lexical and idiomatic meaning of the term exchange, and the phenomenon of semantic exchange is a form of expansion in language, and that the first language scientists They had turned to this And studied under Cairo for different names, as noted above.
This research aims to reveal the quality standards available in press images published in the news sites, the Iraqi News Agency and Al-Mada Press for the period from: 1/9/2019, to: 30/9/2019. The research is a descriptive research, in which the researcher relied on the survey methodology to achieve its objectives. The research reached a number of results, most notably the weak role of photojournalists in the websites and the adoption of those the Internet as a source for obtaining press images published with news and reports through its pages, as well as the neglect of the standard Description/Comment below the press images, which plays an important function in explaining and interpreting them for users.
Political speeches are represented in different shapes as political forum, events or as inaugural speech. This research critically analyzes the inaugural Speech of the President Donald Trump which was delivered on 20th ,January, 2017 from the site<www.cnn.com> retrieved on 10th ,May,2017. The objectives of the study are: First: classifying and discussing well known micro structures (linguistic feature) of the speech, and second: classifying the macro structures i.e. the delivered political inaugural speech in which he includes social structures. To reach to the objectives of the study, the researcher will adopt Norman Fairclough’s three dimensional Analytical Model(1989). Tracing the model, the speech was subm
... Show More
The aim of this work is to study the effect of mud compositions on it’s rheological behavior under high temperature conditions. Seventeen samples of five types of water base mud in which (fresh water bentonite mud. Lignosulphonate mud, gypsum mud, polymer mud, and salt saturated mud) were tested with different temperatures using the fann viscometer model 50-c. All the tested samples, except the fresh water bentonite mud, have the same trend reduction in both plastic viscosity and yield point with increasing temperature. Six rheological models has been adapted: Bingham plastic, power law, Casson model represent the laboratory data accurately
Climate change causes water shortage (water scarcity) in addition to the dams built by neighboring countries, which caused a lack of Iraq's water share. Therefore, evaluating the irrigation system requires considering its suitability, adequacy, and efficiency. Irrigation is considered adequate when it maintains water availability within the root zone, and if the amount to be added is determined, irrigation efficiency becomes possible by avoiding water loss. Babil Governorate is considered one of the agricultural governorates in the country that depends on its irrigation from Shatt Al-Hilla. The study area is the Elaj project. Three fields were selected for the project (B1, B2, and B3). These fields are lo
... Show More
(3)
The paper tries to explore the grammatical phenomenon of rankshift in Systemic Grammar, a functional grammar that establishes five units or the rank scale , : namely sentence, clause phrase, word and morpheme .Rankshift a Hallidayan term , occurs when a given unit is downgraded or shifted down the rank scale and operates further down its rank or a rank equal to itself as when a clause which has to operate in sentence structure operates at q “ qualifier” in a nominal group. The paper , quite significantly, introduces the systemic background that enunciates the systemic theory whose organising concept system rather than structure. The paper then, grammatically explores rankshifted elements, successive rankshifting, degrees of rankshifting
... Show More
Computers have been used for numerous applications involving the automatic or semiautomatic recognition of patterns in image. Advanced manufacturing system requires automated inspection and test method to increase production and yield best quality of product. Methods are available today is machine vision. Machine vision systems are widely used today in the manufacturing industry for inspection and sorting application. The objective of this paper is to apply machine vision technology for measuring geometric dimension of an automotive part. Vision system usually requires reprogramming or parameterization of software when it has to be configured for a part or product. A web camera used to capture an image of an automotive part that has been ch
... Show MorePolitical speeches are represented in different shapes as political forum, events or as inaugural speech. This research critically analyzes the inaugural Speech of the President Donald Trump which was delivered on 20th ,January, 2017 from the site<www.cnn.com> retrieved on 10th ,May,2017. The objectives of the study are: First: classifying and discussing well known micro structures (linguistic feature) of the speech, and second: classifying the macro structures i.e. the delivered political inaugural speech in which he includes social structures. To reach to the objectives of the study, the researcher will adopt Norman Fairclough’s three dimensional Analytical Model(
... Show More
Embedded advertisement constitutes a special kind of communication. As it performs many important roles such as giving information, highlighting the value of the product, and urging the target consumer to buy it by influencing his/ her behavior using an attractive manner of mind and conscience. Both cinema and television are the most prominent and powerful advertising media that enjoy the interest of all audiences and capture most of the advertising spending. As advertisers have paid attention to the importance of indirectly incorporating their products into content that the audience loves and is keen to follow, since the actual impact lies in the inclusion of the product within content that the audience appeals to. Hence, this leads to
... Show More