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Let R be a noncommutative prime ring, U be the left Utumi quotient ring of R, and k, m, n, r be fixed positive integers. If there exist a generalized derivation G and a derivation g (which is independent of G) of R such that [G(xm)xn + xng(xm), xr]k = 0, for all x ∈ R, then there exists a ∈ U such that G(x) = ax, for all x ∈ R. As a consequence of the result in the present article, one may obtain Theorem 1 in Demir and Argaç [10 Demir, Ç., Argaç, N. (2010). A result on generalized derivations with Engel conditions on one-sided ideals. J. Korean Math. Soc. 47(3):483494.[Crossref], [Web of Science ®] [Google Scholar]].  相似文献   
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Russian Journal of General Chemistry - Synthesis of a new series of pyrimidinothienocinnoline derivatives involves the reaction of 9-aminodibenzo[f,...  相似文献   
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Three gemini cationic surfactants with different hydrophobic spacer chain lengths were synthesized and characterized. The inhibition effect of N,N′-bis(2-hydroxyethyl)-N,N′-dimethyl-N,N′-bis(2-(tetradecanoyloxy)ethyl)ethane-1,2-diaminium bromide (G-2); N,N′-bis(2-hydroxyethyl)-N,N′-dimethyl-N,N′-bis(2-(tetradecanoyloxy)ethyl) hexane-1,6-diaminium bromide (G-6); and N,N′-bis(2-hydroxyethyl)-N,N′-dimethyl-N,N′-bis (2-(tetradecanoyloxy) ethyl) dodecane-1,12-diaminium bromide (G-12) on the corrosion of carbon steel in 1.0 M HCl solution at 25–60 °C was studied by weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy. The results show that the synthesized inhibitors are effective inhibitors even at very low concentration, and the adsorption on the carbon steel surface obeys the Langmuir adsorption isotherm. Potentiodynamic polarization curves reveal that the synthesized inhibitors behave as a mixed-type inhibitor. Adsorption of used inhibitors led to a reduction in the double layer capacitance and an increase in the charge transfer resistance. Thermodynamic parameters have been obtained by adsorption theory. Surface activity and corrosion inhibition relationship were discussed. The biodegradability of the synthesized surfactants showed their readily biodegradation in the open environment and were considered as environmentally friendly corrosion inhibitors.

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Self-dual double circulant codes of odd dimension are shown to be dihedral in even characteristic and consta-dihedral in odd characteristic. Exact counting formulae are derived for them, generalizing some old results of MacWilliams on the enumeration of circulant orthogonal matrices. These formulae, in turn, are instrumental in deriving a Varshamov–Gilbert bound on the relative minimum distance of this family of codes.  相似文献   
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It is shown that (1) every almost self-injective group algebra is self-injective and (2) if the group algebra KG is continuous, then G is a locally finite group. Furthermore, it follows that the following assertions are equivalent: a CS group algebra KG is continuous; KG is principally self-injective; the group G is locally finite. __________ Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 11, No. 3, pp. 3–11, 2005.  相似文献   
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Two series of Schiff base amphiphiles were prepared throughout condensation of benzaldehyde or anisaldehyde and three different fatty amines with various alkyl chain length; namely: dodecyl, hexadecyl and octadecyl amine. The chemical structures of the prepared Schiff bases were confirmed using elemental analysis, FTIR, and 1H-NMR spectra. The data of structural analysis for these compounds were confirmed the chemical structures and the purity of the synthesized amphiphiles. The synthesized Schiff base amphiphiles were evaluated as corrosion inhibitors for low carbon steel (mild steel) in various acidic media (HCl and H2SO4) using weight loss technique. The corrosion inhibition measurements of these inhibitors showed high protection of the low carbon steel alloys against corrosion process in the tested acidic media at different periods as well as they have good biocidel effectagainest SRB. The discussion was correlated the efficient corrosion inhibition of these inhibitors to their chemical structures.  相似文献   
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Rheumatoid arthritis (RA) results in increased rate of mortality in millions of people worldwide. Research utilizing Tin oxide – Chitosan- Polyethylene glycol Carvacrol (SCP-CAR) nanocomposites has gained increased attention because of its multipotent properties and application in diverse fields including medicinal preparations. The aim of the investigation was to synthesize and to examine the anti-arthritic ability of SCP-CAR nanocomposites against CFA -induced RA in rats. Arthritis induction was done by injecting 0.1 ml of Complete Freund’s adjuvant (CFA) intradermally. Body weight, weight of organs, hind paw volumes and arthritis score was assessed and the levels of inflammatory modulators such as IL-6, IL-1β, IL-10, TNF-α, PGE2 and COX-2 was examined using assay kits. Lipid peroxidation status, antioxidant enzyme activities and levels of liver function enzymes were evaluated using standard procedures. Histopathological changes observed in hind limb of experimental animals were viewed under microscope using H& E staining. The SCP-CAR nanocomposites treated arthritic animals showed increased bodyweight and reduced hind paw volume, organ weight and arthritis score together with elevated antioxidants status and depleted proinflammatory cytokines. Histopathological observation also showed reduction in bone destruction and penetration of inflammatory cells following treatment with SCP-CAR nanocomposites. Thus, together the findings depict the anti-arthritic and anti-inflammatory potential of SCP-CAR nanocomposites suggesting that it could be used as potent therapeutic agent to treat animals against arthritis induced by CFA.  相似文献   
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