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.
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Different cooking conditions were examined for aluminum content in food cooked while wrapped with aluminum foil. The influence of each anticipated factor (the acidity of the cooking medium, type of acids normally used in cuisines namely acetic and tartaric acids, various cooking temperatures, influence of the presence of sodium chloride salt, the effect of cooking oil, and the length of time of cooking) was studied thoroughly as a function of aluminum degraded out of the aluminum foils to the medium. The experimental samples were digested with nitric acid upon fulfillment of examining each factor separately before quantifying aluminum with the sensitive technique of atomic absorption spectroscopy. The outcomes of the study have shown that t
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he present work, among other previous studies done in our lab, aimed to highlight the histopathological effect of S. xylosus peptidoglycan in comparison to LPS of E. coli. Materials and methods: One hundred and fifty urine specimens were collected from urinary tract infection patients visiting Baghdad hospitals. The histopathological effects of S. xylosus S24 peptidoglycan was studied in the urinary tract of female mice by injecting 5 animal groups at the following concentrations: 1000, 2000, 3000, 4000, and 5000 µg/mL. Another 5 groups were injected with 10, 25, 50, 75, and 100 ng/mL of E. coli (serotype 0128:B12) LPS. Results: Ten isolates were confirmed to be Staphylococcus xylosus. Histopathological study showed different pathological
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AIM: The aim of this study was to measure the prevalence of myeloproliferative disorders in a sample of Iraqi patients and to measure the changes in patients’ blood parameters. BACKGROUND: Myeloproliferative disorders are a group of neoplasms affecting the bone marrow progenitor cells characterized by excess cells with a risk of transforming to acute leukemia. There is a gap in knowledge about the prevalence of Iraqi population. Thus, we investigated the prevalence and distribution of different types of myeloproliferative disorders in a sample of Iraqi patients. MATERIALS AND METHODS: Cross-sectional study is done at the National Center of Hematology from November 2019 till March 2020 on 75 patients who were diagnosed
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Background: Consanguineous marriage is a relationship between biologically related individuals. Genetic factors have a role in gene environment interactions that takes the center stage. The evidence of oral disease (gingivitis and periodontitis) may depend on genetic syndromes, inherited diseases, familial studies etc. The present study aims at assessing dental plaque and gingival health condition in children of inbreeding parents compared with children of outbreeding parents among primary schools in Al-Qasem city/ Babylon governorate in Iraq. Materials and methods: this comparative study included three hundred ninety eight (398) students, 6-12 years old, from 4 primary schools; 199 children had their parents of inbreeding marriage with
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Background: Antibacterial action of root canal filling is an important factor for successful root canal treatment, so the aim of the study was to identify and to compare the antimicrobial effect of new sealer (GuttaFlow) to commonly used endodontic sealers (AH Plus, Apexit and EndoFill) against four endodontic microbes. Materials and methods: Twenty patients aged (30-40) years with infected root canals were selected. Four types of microorganisms were isolated from root canals (E faecalis, Staphylococcus aureus, E coli and Candida albicans) and cultured on Mueller Hinton agar Petri-dishes. After identification and isolation of bacterial species, agar diffusion method was used to assess the antibacterial action of four contemporary endodontic
... Show MoreThe experiments were conducted in laboratory conditions of a temperature of 25± 2C and relative moisture of 40± 5 % to evaluate the effectiveness of the cinnamon, lavender and clove essential oils on some biological life aspects of cowpea beetle, C. maculates. Results of the obligative experiment for the effect of the oils on insect adult killing showed that the concentration of 5% caused a mortality percentage averaged 13.33% of the insect males. The mortality percentage of the insect females was 11.3% for the cinnamon and lavender oils. The lavender oil had the lowest effect on adult killing, not exceeding 0. For the effect of the oils on egg laying, clove oil affected the number of eggs highly at the concentration of 5%, result
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Stable isotopes 18O/16O and 13C/12C in the carbonate rocks of the Mishrif Formation are examined here to define the depositional characters in the basin includes paleo temperatures and paleo depth. The Mishrif formation (Cenomanian – Early Turonian) has extensive distribution in Iraq and Middle East. Mishrif Formation composed of organic detrital limestone. Four boreholes in four oilfields, Noor – well (11), Amarah – well (14), Buzurgan – well (24), Halfaya – well (8), in south east of Iraq have been studied. The studied samples have negative δ18O isotope values studied well, with Average (-4.11‰), (-4.47‰), (-4.48‰), (-4.18‰) in the studied wells res
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ABSTRACT Wound is damage or disruption to the normal anatomical structure and function. Carrageenan is sulphated polysaccharide found in Gigartina, Chondrus and Eucheuma species in the red algal family. Having anticancer, anti-inflammatory and renewal of tissues. Our study aimed to detect the role of kappa carrageenan in the burned skin wound repair. Skin burn were performed in the right and left cheek of 20 male rats (aged 7-8 weeks weighing 300-350 g). Burned skin rats were categorized into two equal groups. Burned areas of right side were treated with a local application of 1 ml of kappa carrageenan solution once daily (treatment group) and the left side receive no treatment (control group). After 5, and 10 days, 5 rats from each
... Show MoreHands have consistently been an important vehicle in the transmission of disease (1). Thus, thorough hand-washing remains the single most important factor in preventing infection specially in hospitals and labs.Twenty-nine non-clinical volunteers (do not work or come in contact with a clinical or hospital setting) that lacked visible skin injuries, eczema or apparent skin disease were used, those subjects were all tested by a material of each of the three used in the study weekly and laboratory tests were done pre- and post washing.All three material were effective , Eugenol extract as effective as the bar and lotion soap. And this was confirmed statistically.Eugenol has a great antibacterial action even in small concentration and t
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