排序方式: 共有17条查询结果,搜索用时 15 毫秒
11.
Sathiyendiran M Chang CH Chuang CH Luo TT Wen YS Lu KL 《Dalton transactions (Cambridge, England : 2003)》2007,(19):1872-1874
A rigidity-modulated strategy for the conformational control of a flexible motif in the self-assembly of metallacycles is described; the span of the rigid ligand directs the conformation of the flexible motif by fixing the M ... M separation, thereby dictating the structure of the metallacycles. 相似文献
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Water-stable and cavity-contained rhenium metallacycles were synthesized, and their ability to selectively interact with volatile organic compounds (VOCs) systematically studied using attenuated total reflection infrared (ATR-IR) spectroscopy. Integrating the unique properties of rhenium metallacycles into optical sensing technologies significantly improves selectivity in detecting aromatic compounds. To explore the interaction of rhenium metallacycles with VOCs, the surface of ATR sensing elements was modified with the synthesized rhenium metallacycles and used to detect VOCs. The results indicate that rhenium metallacycles have crown ether-like recognition sites, which can selectively interact with aromatic compounds, especially those bearing polar functional groups. The IR absorption bands of rhenium metallacycles shift significantly upon adsorption of aromatic VOCs, revealing a strong interaction between the tetra-rhenium metallacycles and guest aromatic compounds. Optimizing the thickness of the metallacycles coated on the surface of the sensing element led to rapid response in detection. The dynamic range of response was generally up to 30 mg/L with detection limits ca. 30 μg/L. Further studies of the effect of interferences indicate that recovery can be higher than 95% for most of the compounds tested. The results on the flow-cell device indicated that the performances were similar to a static detection system but the detection of VOCs can be largely simplified. 相似文献
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The interaction(s) of Toluidine Blue O (TBO) with DNA was investigated using absorption and emission spectral methods. The
binding of TBO with DNA was understood from the observed hypochromism in the absorption spectra and decrease in the emission
intensity of TBO. From the absorption and emission spectral data, two binding constants were estimated for the binding of
TBO with DNA. Based on the binding constant values both intercalative and electrostatic interactions of TBO with DNA were
suggested. The TBO-DNA binding constant values reveal that the electrostatic interaction of TBO with DNA is weaker than the
intercalative interaction. The emission quenching and salt effect studies showed that the TBO was partially intercalated with
DNA. The two modes of binding between TBO and DNA may lead to the formation of bridging of a pair of DNA duplexes by TBO molecule.
The electrostatic interaction is more important for the formation of the bridged structure of TBO with DNA. This was verified
by studying the interaction of an anionic dye, Eosin Y (EY). 相似文献
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Murugavel R Sathiyendiran M Pothiraja R Butcher RJ 《Chemical communications (Cambridge, England)》2003,(20):2546-2547
Molecular structure of [Cu(dtbp)2(phen)(OH2)] (dtbp-H = di-tert-butylphosphate, phen = 1,10-phenanthroline), determined at 293, 203 and 93 K, provides useful snap-shots of O-H bond activation of a metal-bound water, which is aided by an intramolecular P=O...H-O hydrogen bonding interaction. 相似文献
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Microchimica Acta - The article describes a simple method for the rapid photometric and visual detection of sulfide in water samples. Silver nanoparticles were capped with chitosan (chit-AgNPs) and... 相似文献
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Bhattacharya D Sathiyendiran M Wu JY Chang CH Huang SC Zeng YL Lin CY Thanasekaran P Lin BC Hsu CP Lee GH Peng SM Lu KL 《Inorganic chemistry》2010,49(22):10264-10272
Self-assembled, chair-shaped dirhenium(I) macrocyclic compounds featuring the two different bis-chelating quinone dianions (1, L = dhnq(2-); 2, L = dhaq(2-); H(2)dhnq = 6,11-dihydroxy-5,12-naphthacenedione; H(2)dhaq = 1,4-dihydroxy-9,10-anthraquinone) that interface with two fac-Re(CO)(3) cores and a ditopic semirigid N-donor 1,4-bis(5,6-dimethylbenzimidazol-1-ylmethyl)naphthalene (L' = p-NBimM) ligand coordinated to the remaining orthogonal site were prepared in high yields. Their structures were confirmed by single-crystal X-ray diffraction analysis. Electrochemical assessments, using cyclic voltammetry (CV) and UV-vis-NIR spectroelectrochemistry (SEC), revealed the existence of two well-separated, single-electron quinone ligand-centered, reversibly accessible 0, -1, and -2 redox states. Among the two singly reduced radical complexes, the symmetrically bridged quinone complex 1(?-), showed a strong absorption in the NIR regions, which was not observed for the neutral and doubly reduced states, analogous to that of the free dhnq(3?-) quinone. In contrast, when 2 was reduced to 2(?-), a broad signal at 866 nm was observed, very similar to the reduced dhaq(3?-) quinone. This difference in spectral behavior in the singly reduced states is likely due to the annealed benzene ring in 1 and dhnq(2-) because of its symmetrical π-electron system, which is perturbed to a lesser degree compared to asymmetric 2 and dhaq(2-). Reduction to 1(?-) produces a small but not negligible g factor anisotropy (Δg = 0.024) in the electron spin resonance (ESR) signal, indicative of a very small metal-centered spin (5%), but 2(?-) shows a g value in the expected range for organic radicals (no detectable Δg). Thus, the combined investigations reveal that the singly reduced metallacycles are best described as being highly stable, noncommunicating, localized, quinonoid-centered radical complexes, [(CO)(3)Re(I)(μ-L(3?-))(μ-L')Re(I)(CO)(3)](?-). 相似文献