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- MakaleYalnız künye2011Microwave-assisted synthesis and characterization of novel symmetrical substituted 19-membered tetrathiadiaza metal-free and metallophthalocyanines and investigation of their biological activities
Nas, Asiye; Kaya, Elif Celenk; Kantekin, Halit; Sökmen, Atalay; Çakir, Volkan
This work reports on a new symmetrically substituted metal-free phthalocyanine and its transition metal complexes which were prepared by a condensation of N,N'-[propan-1,3-diilbis(tiyoetan-2,1-diil)]bis(4-methylbenzenesulfonamid) (1) and 1,2-bis(2-iodomercaptoethyl)-4,5-dicyanobenzene (2) with NiCl(2), ZnCl(2), CoCl(2), CuCl(2), and PbO salts in 2-(dimethylamino) ethanol, respectively. The phthalocyanines bearing thia and aza donor atoms at the peripheral position were characterized by IR, UV-Vis, (1)H NMR, (13)C NMR, Mass spectra, and elemental analysis data. The thermal behaviors of 4-9 were investigated by TG/DTA. Novel phthalocyanines were also investigated for enlightening their possible biological activities by employing antimicrobial (antibacterial and antifungal), antineoplastic and antioxidative assays. Of all tested, four samples exhibited antimicrobial activity against test microorganisms, among which, Branhamella catarrhalis was the most sensitive one with a MIC value around 0.312 mg/mL followed by a yeast, Candida albicans (MIC. 0.625 mg/mL). Due to their colored nature, the samples were found not to be applicable for antioxidative and antineoplastic assays. (C) 2011 Elsevier B. V. All rights reserved.
- BildiriYalnız künye2011Hydroxyapatite production on ultrafine-grained pure titanium by micro-arc oxidation and hydrothermal treatment
Alsaran, A.; Purcek, G.; Hacisalihoglu, I.; Vangolu, Y.; Bayrak, O.; Karaman, I.; Celik, A.
In this study, pure-Ti (Grade-2) was severely plastically deformed by equal-channel angular extrusion (ECAE) to improve its strength, and then subjected to micro arc oxidation (MAO) and hydrothermal treatment (HT) to achieve improved surface behavior with hydroxyapatite (HA)-containing titania (TiO(2)) coating. Microstructure, tensile properties and wear behavior of UFG Ti were investigated systematically before and after surface modification. ECAE considerably enhanced the strength of coarse-grained (CG) Ti by forming an ultra-fine grained (UFG) microstructure with high dislocation density. The application of MAO with or without HT did not cause remarkable decrease in strength and ductility of CG and UFG Ti, but resulted in a considerable increase in its wear resistance and osseointegration due to the formation of hard and adhered HA-containing TiO2 coating on the surface. It can be concluded that the use of ECAE plus MAO/HA coating provides a simple and effective procedure to obtain pure Ti with high strength and high wear resistance. The improved bulk and surface properties can make this biocompatible material a good potential candidate for biomedical applications instead of alloys including toxic elements. (C) 2011 Elsevier B.V. All rights reserved.
- DergiJOURNAL OF ORGANOMETALLIC CHEMISTRY
- DergiSURFACE & COATINGS TECHNOLOGY