Two homopolymeric and three copolymeric additives for base oil were synthesized using octyl acrylate (OA) and tert-butyl acrylamide (TBA) monomers. The two additives named P1 and P2 are the homopolymers of TBA and OA, respectively, whereas copolymeric additives named Co1, Co2, and Co3 were synthesized by varying the ratios of TBA:OA as 1:3, 3:1 and 1:1, respectively. The prepared polymers were characterized by Fourier Transform Infrared (FTIR). Based on the solubility of synthesized polymers in base oil and reactivity ratios of TBA/OA copolymer (0.222, 0.434) calculated by Fineman-Ross method, P2, Co1, Co2 and Co3 were selected to evaluate their performance as pour point depressant (PPD), viscosity improver (VII), and anticorrosion additives in base oil. Additives P2 and Co1 showed the best performance as (PPD) and (VII) whereas Co2 and Co3 revealed the best performance as anticorrosion additives. The flash point of base oil increased as a concentration of polymeric additives increased in the base oil. In addition to study the performance of synthesized polymers as lubricant additives, the capability of polymers for removing CuII from synthetic wastewater was also investigated. Different parameters such as pH of solution, contact time, and CuII concentration were changed in order to study their effect on adsorption capacity of polymers. Generally, polymers with high TBA content such as P1, Co2, and Co3 showed good performance in removing CuII.
Power-electronic converters are essential elements for the effective interconnection of renewable energy sources to the power grid, as well as to include energy storage units, vehicle charging stations, microgrids, etc. Converter models that provide an accurate representation of their wideband operation and interconnection with other active and passive grid components and systems are necessary for reliable steady state and transient analyses during normal or abnormal grid operating conditions. This paper introduces two Laplace domain-based approaches to model buck and boost DC-DC converters for electromagnetic transient studies. The first approach is an analytical one, where the converter is represented by a two-port admittance model via mo
... Show MoreSphingolipids are key components of eukaryotic membranes, particularly the plasma membrane. The biosynthetic pathway for the formation of these lipid species is largely conserved. However, in contrast to mammals, which produce sphingomyelin, organisms such as the pathogenic fungi and protozoa synthesize inositol phosphorylceramide (IPC) as the primary phosphosphingolipid. The key step involves the reaction of ceramide and phosphatidylinositol catalysed by IPC synthase, an essential enzyme with no mammalian equivalent encoded by the AUR1 gene in yeast and recently identified functional orthologues in the pathogenic kinetoplastid protozoa. As such this enzyme represents a promising target for novel anti-fungal and anti-protozoal drugs. Given
... Show MoreThe current research aims to investigate the skills of the intended meaning beyond the context when reading poetry among fifth literary students. To achieve the aim of the research, the researcher has followed the descriptive approach and used two tools: an open questionnaire that includes an inquiry about the skills of the intended meaning beyond the poetic context, and a closed questionnaire that were examined by the juries, and modified accordingly. Besides, its validity and stability were examined by applying the study on an exploratory sample of (15) teachers to reach its final version and determine the time required to answer it. Then, the researcher applied it on the research sample of (9
... Show MoreL-Thyroxine(T4) and triiodothyronine(T3)are iodine-containing hormones produced from thyroglobulin in the thyroid follicular cells. The stimulation of metabolic rate and regulation of growth and development by these hormones appear to be due to their effects on DNA transcription and, thus, protein synthesis. The aqueous extract of vitis vinifera L. was investigated for its effect on hormones in rabbits. The aqueous extract of plant at a dose level of 50µg/rabbit showed highly significant (p<0.05)on levels of hormones T4, TSH but TSH no significant. L-thyroxine sodium treated group showed a highlysignificant increase in T3 and T4 while there was a highly significant decrease in TSH. From the above results, it is concluded for the first time
... Show MoreAim: The study designed to evaluate the Geno-protective effect of green tea extract against genotoxicity induced by metronidazole and tinidazole. Methods: Thirty-six mice were used, For each experiment, The animals divided into 6 groups: Group I- Negative control administered distilled water; Group II-Healthy mice treated with metronidazole alone, Group III- Healthy mice treated with tinidazole alone; Group IV- Healthy mice administered green tea extract alone Group V- Healthy mice treated with metronidazole, followed by green tea extract administration, Group VI- Healthy mice treated with tinidazole, followed by administration of green tea extract. Results: treatment with Tinidazole significantly increase total chromosomal aberration (0.18
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