排序方式: 共有45条查询结果,搜索用时 19 毫秒
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Constable EC Dunphy EL Housecroft CE Neuburger M Schaffner S Schaper F Batten SR 《Dalton transactions (Cambridge, England : 2003)》2007,(38):4323-4332
Ligands in which multiple metal-binding domains are linked by a metal-containing moiety rather than a conventional organic group are described as "expanded ligands". The use of 4,4'-difunctionalised {Ru(tpy)(2)} units provides a linear spacer between metal-binding domains and we have extended this motif to expanded ligands containing two carboxylic acid metal-binding domains. In this paper, we describe the synthesis and structural characterisation of ruthenium(ii) complexes of 2,2':6',2'-terpyridine-4'-carboxylic acid and 4'-carboxyphenyl-2,2':6',2'-terpyridine. The ability of the ruthenium(ii) centre to charge compensate deprotonation of the carboxylic acid leads to Zwitterionic complexes and three representative compounds have been structurally characterised. 相似文献
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DR. E. W. J. Mitchell 《Contemporary Physics》2013,54(3):217-222
The accurate measurement of the thermal conductivity of metals still poses considerable experimental difficulty. The reasons for this, and the main ways in which the problem has been approached, are summarized. A detailed examination of the development in technique and methods of measurement shows that while most of the steady-state methods introduced over 50 years ago are still being improved, the emphasis in the last few years has been on the development of methods which give more rapid results, particularly at high temperatures. 相似文献
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Patra SK Ahmed R Whittell GR Lunn DJ Dunphy EL Winnik MA Manners I 《Journal of the American Chemical Society》2011,133(23):8842-8845
Solution self-assembly of the regioregular polythiophene-based block copolymer poly(3-hexylthiophene)-b-poly(dimethylsiloxane) yields cylindrical micelles with a crystalline P3HT core. Monodisperse nanocylinders of controlled length have been prepared via crystallization-driven self-assembly using seed micelles as initiators. 相似文献
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Beves JE Dunphy EL Constable EC Housecroft CE Kepert CJ Neuburger M Price DJ Schaffner S 《Dalton transactions (Cambridge, England : 2003)》2008,(3):386-396
A comparative structural and spectroscopic investigation of the complexes [M(1)2]2+, [M(2)2]2+ and [M(3)2]2+ in which M = Fe or Ru, and ligands 1, 2 and 3 are 4'-(2-pyridyl)-, 4'-(3-pyridyl)- and 4'-(4-pyridyl)-2,2':6',2"-terpyridine, respectively, is reported. The complexes [Ru(1)2]2+, [Ru(2)2]2+ and [Ru(3)2]2+ undergo mono- and bis-N-methylation. The consequences of methylation on the absorption spectra and electrochemical properties are discussed; the solid-state structure of the bis(N-methylated) derivative of [Ru(2)2][PF6]2 is presented. 相似文献
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Michael J. Dunphy Annette M. Sysel Joseph A. Lupica Kristie Griffith Taylor Sherrod Joseph A. Bauer 《Chromatographia》2014,77(7-8):581-589
Nitrosylcobalamin (NO-Cbl), a novel vitamin B12 analog and anti-tumor agent, functions as a biologic ‘Trojan horse’, utilizing the vitamin B12 transcobalamin II transport protein and cell surface receptor to specifically target cancer cells. A stability-indicating HPLC method was developed for the detection of NO-Cbl during forced degradation studies. This method utilized an Ascentis® RP-Amide (150 mm × 4.6 mm, 5 μm) column at 35 °C with a mobile phase (1.0 mL min?1) combining a gradient of methanol and an acetate buffer at pH 6.0. Detection wavelengths of 450 and 254 nm were used to detect corrin and non-corrin-based products, respectively. NO-Cbl, synthesized from hydroxocobalamin and pure nitric oxide gas, was subjected to degradative stress conditions including oxidation, hydrolysis and thermal and radiant energy challenge. The method was validated by assessing linearity, accuracy, precision, detection and quantitation limits and robustness. The method was applied successfully for purity assessment of synthesized NO-Cbl and for the determination of NO-Cbl during kinetic studies in aqueous solution and in solid-state degradation assessments. This HPLC method is suitable for the separation of cobalamins in aqueous and methanolic solutions, for routine detection of NO-Cbl and for purity assessment of synthesized NO-Cbl. Additionally, this method has potential application in identification and monitoring of diseases involving altered nitric oxide homeostasis where vitamin B12 therapy is utilized to scavenge excess nitric oxide, subsequently resulting in the in vivo production of NO-Cbl. 相似文献
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Abstract Bragg reflection gratings and out-coupling taps for sensors can be written holographically within the core of many commercial fibers available today. The gratings appear to be permanent and have been tested to temperatures in excess of 500°C. Quasi-distributed temperature, strain, pressure, chemical, and interferometric sensors can be made with the wavelength selective, reflection gratings, and taps. The fiber gratings, and the different types of sensors they can make, conveniently lend themselves to (wavelength-division multiplexing) WDM, (time-division multiplexing) TDM, and (frequency-division multiplexing) FDM types of multiplexing schemes. Instrumentation to detect the multiple sensors and measure their spectral shift for localized and quasi-distributed sensing is currently under development. 相似文献