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881.
Synthesis,Spectral Characterization and Antimicrobial Activity of Some Transition Metal Complexes of 1,3‐Bis(1H‐benzimidazol‐2‐yl)‐2‐oxapropane 下载免费PDF全文
Aydin Tavman Adem Çinarli Demet Gürbüz A. Seher Birteksöz Tan M. A. Faruk Öksüzömer Mayram Tüysüz Mehmet Ali Gürkaynak Bahattin Yalçin 《中国化学会会志》2014,61(12):1377-1387
1,3‐Bis(1H‐benzimidazol‐2‐yl)‐2‐oxapropane ( L ) complexes with Fe(NO3)3, CoCl2, Co(NO3)2, Ni(NO3)2, CuCl2, Cu(ClO4)2, PdCl2, CdI2, Hg(NO3)2 were synthesized and characterized by elemental analysis, molar conductivity, magnetic moment, TGA, FT‐IR, NMR, ESI‐MS, fluorescence spectroscopy. Also, the crystal structure of 1,3‐bis(1H‐benzimidazol‐2‐yl)‐2‐oxapropane]dichlorocobalt(II), [Co( L )Cl2], complex is reported that it has distorted trigonal bipyramidal geometry. Antibacterial activities of the compounds were evaluated using the disk diffusion method against six bacteria and Candida albicans. The Hg(II) complex shows superior activity toward S. epidermidis and E. coli whereas the other complexes are ineffective except the Co(NO3)2 complex: it showed weak activity toward all of the microorganisms. 相似文献
882.
The Photolyase/Cryptochrome Family of Proteins as DNA Repair Enzymes and Transcriptional Repressors 下载免费PDF全文
883.
A new, simple synthesis of succinimides is described. The reactions were carried out under the ultimate green conditions excluding both catalyst and organic solvent by applying simple stirring at 100?°C. A wide variety of N-susbstituted succinimides have been prepared in high yields by using succinic acid and primary amines in hot water. Yield of N-alkyl substituted succinimides were found to be higher than those of N-aryl substituted succinimides. 相似文献
884.
Mehmet Salih Dinleyici 《Fiber and Integrated Optics》2013,32(1):87-95
The effective device length of fiber-half coupler geometry has been investigated by the modal method, and the minimum device length required by the device operation for a slab fiber evanescent coupler has been computed. 相似文献
885.
An alternative method has been developed for the anomeric deacetylation of fully acetylated carbohydrate derivatives using
zinc acetate dihydrate as a catalyst in methanol under mild conditions. The experimental simplicity, low cost, acceptable
yield, use of a readily handled acidic catalyst, and the environmentally benign nature are some of the advantages of this
method. 相似文献
886.
887.
Mustafa Soylak Sibel Saracoglu Latif Elci Mehmet Dogan 《International journal of environmental analytical chemistry》2013,93(4):225-231
A preconcentration/separation method for the atomic absorption spectrometric determinations of Cu(II), Ni(II) and Pb(II) ions in seawater have been established by using a chromatographic column filled Amberlite XAD-1180. The recoveries of Cu(II), Ni(II) and Pb(II) ions were quantitative (> 95%) at pH 8-9. The influences of the various analytical parameters including the amount of calmagite, amount of Amberlite XAD-1180, eluent type, etc. were investigated. The influence of the seawater matrix was also examined. Simultaneous enrichment and determination of copper, nickel and lead ions in seawater are possible with satisfactory results (recoveries > 95%, RSD <9%). 相似文献
888.
A hybrid material system consisting of (3-glycidyloxypropyl)trimethoxysilane and dimethyldimethoxysilane as matrix materials and diphenyldimethoxysilane (DPDMS) as both a matrix material and a potential thermal stabiliser by the sol-gel method. A detailed thermogravimetric analysis study of the influence of processing parameters, including DPDMS content, UV irradiation and sol ageing, on the thermal stability of the resultant thin films was presented. FT-IR spectroscopy was used to monitor the changes in the relative amount of epoxy rings in the system during processing. It was demonstrated that the crosslinking of epoxy groups in the structure is the primary reason for changes in the thermal stability of the system. It was also shown that the thermal stability, in terms of 10% mass loss, of the material system could be improved up to 280 °C, by adjusting the preparation conditions, compatible with several subsequent high temperature optoelectronic integration processes. 相似文献
889.
Mehmet Aslanoglu 《Analytical sciences》2006,22(3):439-443
The interaction of proflavine with herring sperm DNA has been investigated by cyclic voltammetry and UV-Vis spectroscopy as well as viscosity measurements. Shifts in the peak potentials in cyclic voltammetry, spectral changes in UV absorption titration, an increase in viscosity of DNA and the results of the effect of ionic strength on the binding constant strongly support the intercalation of proflavine into the DNA double helix. The binding constant for the interaction between proflavine and DNA was K = 2.32 (+/- 0.41) x 10(4) M(-1) and the binding site size was 2.07 (+/- 0.1) base pairs, estimated in voltammetric measurements. The value of the binding site size was determined to be closer to that expected for a planar intercalating agent. The standard Gibbs free-energy change is ca. -24.90 kJ/mol at 25 degrees C, indicating the spontaneity of the binding interaction. The binding constant determined by UV absorption measurements was K = 2.20 (+/- 0.48) x 10(4) M(-1), which is very close to the value determined by cyclic voltammetry assuming that the binding equilibrium is static. 相似文献
890.
In this study, we report a new ligand, 6-hexyloxy-3-[p-(3′,4′-dicyanophenoxy)phenyl]coumarin, and its fluorescent tetrasubstituted phthalocyanines {M[Pc(OBzCou)4], M = 2H, Zn(II), Co(II); Bz: Benzene}. The effect of the coumarin derivative on the intensity of the fluorescence spectra of the metal-free (H2Pc) and zinc phthalocyanine (ZnPc) derivatives was investigated. The change of the emission properties of both the coumarin moieties and the phthalocyanine core in the presence of the metal ion and the ring-opening reaction of the coumarin were studied by means of steady-state fluorescence spectroscopy. The radiative decay of the Pcs and the treated coumarin substituents bound to the Pcs was examined. The novel chromogenic compounds were characterized by elemental analysis, 1H NMR, 13C NMR, Maldi-TOF, IR and UV–Vis spectral data. The photophysical properties of the Pcs are extensively affected by their state of aggregation: in particular, dimerization and aggregation result in a remarkable modification of the absorption and emission bands and may induce significant quenching of the usually strong Pc fluorescence. The electronic spectra exhibit a band of coumarin identity together with characteristic Q and B bands of the phthalocyanine core. 相似文献