ABSTRACT: Polypyrrole and polypyrrole / silver nanocomposites were fabricated by in-situ polymerization employing Ammonium Persulphate as an oxidizing agent. Nanocomposites were synthesized by combining polypyrrole and silver nanoparticles in various weight percentages (0.1%, 0.5%, 3%, 5% and 7% wt.). Crystallographic data were collected using X-ray diffraction. PPy particles were found to have an orthorhombic symmetry. In contrast, PPy/Ag nanocomposites were reported to have monoclinic structure. The crystallite size was determined by XRD using Scherrer equation and considered to be within 49 nm range. DC conductivity of pelletized samples was evaluated in the temperature range of 323.15k to 453.15k. The conductivity displayed an increase when the temperature is increased from 323.15k to 453.15k. Activation energies were determined from plots of Arrhenius for all nanocomposites. The findings indicated that the activation energy decrease with increasing the weight percentage of Ag nanoparticles in the nanocomposites.
The methods used by the print media (press) is varied in conveying its messages and its orientations to the readers. But language takes the leading method among these methods, or a real competitor - so far - due to the characteristics and advantages of languages, including: ease, abbreviation, and development, etc.
In the midst of such events, political tensions, and what they carry of the global developments, and among which was the most important the fall of the former Iraqi regime in the spring of 2003, the press had the greatest share, and a large portion on the level of monitoring, analyzing, and interpreting the various consequences of the event. The interpreting of the news varies according to the evolving political trends
... Show MoreThis case–control study aimed to investigate the relationship between the hypoxia‐related biomarker hypoxia‐inducible factor‐1α (HIF‐1α) and the epithelial‐mesenchymal transition (EMT)–associated markers E‐cadherin (E‐CAD) and N‐cadherin (N‐CAD) in saliva among smokers and nonsmokers with and without periodontitis and to assess their association with clinical periodontal parameters.
A case–control study was conducted, including 88 participants equally a
This study compared the effects of citric acid (CA) derived from microbial fermentation using Aspergillus niger (400 mg kg-1) and natural extraction from Citrus limon (400 mg kg1) in albino mice. Parameters assessed included cytogenetic damage via the micronucleus (MN) assay, immunological response through immunoglobulin (IgA, IgG, IgM) titers, and hepatoprotective activity based on liver enzyme levels (AST, ALT, ALP) and histopathological inves tigation. Mice were divided into six groups (n=10/group) as follows: (1) negative control, (2) carbon tetrachloride (CCl₄ 0.02%), (3) lemon CA, (4) A. niger, (5) CCl₄ + lemon CA, and (6) CCl₄ + A. niger CA. The CCl4 group exhibited a significantly higher MN frequency (0.06 ± 0.008) compa
... Show More‘Ode to a Nightingale’(1819) is a typical poem of a Romantic poet like John Keats, but
‘The Nightingale’(1798) is an uncharacteristic poem of a Romantic poet like Coleridge.
The paper proposes a comparison between Coleridge’s ‘The Nightingale’ and Keats’
‘Ode to a Nightingale’.Coleridge’s poem diverges from the Romantic norm; it carries some
characteristics new to Romantic poetry like the realistic and objective portrayals of nature and
the nightingale, while Keats’ poem adhere to the characteristics of Romantic poetry; it
portrays nature and the nightingale subjectively and unrealistically. Coleridge’s poem is very
much influenced by the scientific approaches to environment, and natural his
A reliable and environmental analytical method was developed for the direct determination of tetracycline using flow injection analysis (FIA) and batch procedures with spectrophotometric detection. The developed method is based on the reaction between a chromogenic reagent (vanadium (III) solution) and tetracycline at room temperature and in a neutral medium, resulting in the formation of an intense brown product that shows maximum absorption at 395 nm. The analytical conditions were improved by the application of experimental design. The proposed method was successfully used to analyze samples of commercial medications and verified throughout the concentration ranges of 25–250 and 3–25 µg/mL for both FIA and batch procedures, respecti
... Show MoreBackground: Obesity is a serious public health concern that has reached epidemic proportions; the prevalence, as well as the severity of obesity in adolescents is increasing at an alarming rate. A close relationship was found between weight status and dental caries. Thus this research aimed to assess the prevalence and severity of dental caries among overweight adolescent females in relation to physicochemical characteristics of stimulated whole saliva in comparison with normal weight adolescent females. Materials and methods: The total sample involved for nutritional status assessment is composed of 2678 females aged 13-15 years. This was performed using Body Mass Index specific for age and gender according to CDC growth chart (2000). The
... Show MoreАннотация
В статье считается национально-культурная специфика и языковое изменчивость выражения заключений в художественном тексте. В настоящее время в изучении художественного текста существует множество взаимодополняющих подходов и концепций, которые способствуют лучшему пониманию его языковых и культурных аспектов. Художественный текст как «воспроизведение» и от
... Show MoreInfluence of combined square nozzle with helical tape inserted in a constant heat flux tube on heat transfer enhancement for turbulent airflow for Reynolds number ranging from 7000 to 14500 were investigated experimentally. Three different pitch ratios for square nozzle (PR = 5.8, 7.7 and 11.6) according to three different numbers of square nozzle (N = 3, 4 and 5) and constant pitch ratios for helical tape were used. The results observed that the Nusselt number and friction factor for combination with winglets were found to be up to 33.8 % and 21.4 %, respectively higher than nozzle alone for pitch ratio PR=5.8. The maximum value of thermal performance for using combination with winglets was about 1.351 for pitch ratio= 5.8. Nusselt numb
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