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171.
Colette E. McGarvey † David A. Holden Morris F. Tchir 《Photochemistry and photobiology》1992,55(2):301-304
The quantum yield values for the decomposition of 12-azido-1-diazo-2-dodecanone, 1-diazo-11-dodecanone, 1-diazo-17-octadecen-2-one, stearoyl azide and 10-undecenyl azidoformate in hexane were determined. It was found that the compounds decomposed with relatively high quantum yields, suggesting their use in biological applications, especially for binding phospholipids to membrane proteins. 相似文献
172.
Colette Deschamps-Vallet Jean-Baptiste Ilotse Michèle Meyer-Dayan Darius Molho 《Tetrahedron letters》1979,20(13):1109-1112
Easy conversion of isoflavylium salts into 2-arylbenzofurans under mild perhydrol oxidation conditions suggests an alternative biogenetic pathway. 相似文献
173.
Reichwagen J Hopf H Del Guerzo A Belin C Bouas-Laurent H Desvergne JP 《Organic letters》2005,7(6):971-974
[structure: see text] Rod-shaped 2,3-di-alkoxytetracenes, soluble in common organic solvents, have been synthesized and studied for their gelling ability in organic solvents and their unusual UV-visible spectroscopic properties. 相似文献
174.
Björn Gustafsson Jacqueline Mossino Colette Picard 《Annali di Matematica Pura ed Applicata》1992,162(1):87-104
Let \(\Omega = \Omega _0 \backslash \bar \Omega _1\) be a regular annulus inR N and \(\phi :\bar \Omega \to R\) be a regular function such that φ=0 on ?Ω0, φ=1 on ?Ω1 and ▽φ ≠ 0. Let Kn be the subset of functions v ε W1,p (Ω) such that v=0 on ?Ω0, v=1 on ?Ω1, v=(unprescribed) constant on n given level surfaces of φ. We study the convergence of sequences of minimization problems of the type $$Inf\left\{ {\int\limits_\Omega {\frac{1}{{a_n \circ \phi }}G(x,(a_n \circ \phi )\nabla v)dx;v \in K_n } } \right\},$$ where an ε L∞ (0,1) and G: (x, ζ) ε Ω × RN → G(x, ζ εR is convex with respect to ξ and verifies some standard growth conditions. 相似文献
175.
Richard A. Houghten Sylvie E. Blondelle Colette T. Dooley Barbara Dörner Jutta Eichler John M. Ostresh 《Molecular diversity》1996,2(1-2):41-45
Summary A positional scanning tetrapeptide library was chemically modified through alkylation and/or reduction of the amide bonds, thus generating three new combinatorial libraries with physico-chemical properties very different from the parent peptide library (libraries from libraries). Specific results were obtained with each of these libraries upon screening in -opioid receptor binding and microdilution antimicrobial assays, illustrating the potential of the libraries from libraries concept for the efficient generation of a variety of chemically diverse combinatorial libraries. 相似文献
176.
177.
178.
Sophie Barrau Philippe Demont Cline Maraval Alain Bernes Colette Lacabanne 《Macromolecular rapid communications》2005,26(5):390-394
Summary: The glass transition temperatures of conducting composites, obtained by blending carbon nanotubes (CNTs) or polypyrrole (PPy) particles with epoxy resin, were investigated by using both differential scanning calorimetry (DSC) and dynamical mechanical thermal analysis (DMTA). For both composites, dc and ac conductivity measurements revealed an electrical percolation threshold at which the glass transition temperature and mechanical modulus of the composites pass through a minimum.
179.
Dry poly(vinyl alcohol) (PVA) formulations are widely used in the field of micro‐optics for holographic recording and fabrication of micro‐optical elements, but very little is known about the recording mechanism and even less in systems generating relief elements through a self‐developing process. Thus, the recording of relief gratings with pitches ranging from 5 to 120 l/mm was examined with reference to the average weight of PVA and degree of hydrolysis. The slit width to pitch ratio in the amplitude mask used for photopatterning appeared to be also a controlling factor in the response of sensitive materials. A semiquantitative model was introduced to account for the final shape of the photogenerated relief. It determined the respective parts played by diffusion and capillary convection, i.e., convection processes resulting from gradients of chemical potential and surface tension, respectively, and identified the experimental key parameters governing their interrelation. This work sheds new light on the optimization of the patterning conditions of amplitude masks and is expected to open up new vistas in the replication of computer‐generated holograms. 相似文献
180.
This study focuses on the optimisation and characterisation of novel, ORganically MOdified SILicate (ORMOSIL)-based, hybrid sensor films for use in the detection of O(2) on a breath-by-breath basis in human health monitoring applications. The sensing principle is based on the luminescence quenching of the O(2)-sensitive ruthenium complex [Ru(ii)-tris(4,7-diphenyl-1,10-phenanthroline)], which has been entrapped in a porous sol-gel film. The detection method employed is that of phase fluorometry using blue LED excitation and photodiode detection. Candidate sensor films include those based on the organosilicon precursors, methyltriethoxysilane, ethyltriethoxysilane, n-propyltriethoxysilane and phenyltriethoxysilane. While it has been established previously by the authors that these films exhibit a stable, highly sensitive response to O(2), this study focuses on selecting the material most suited for use in a breath monitor, based on the sensitivity, response time and humidity sensitivity of these films. Key parameters to be optimised include the O(2) sensitivity of the film and the film polarity, i.e. the degree of hydrophobicity. These parameters are directly linked to the precursors used. In this study a n-propyltriethoxysilane-derived O(2) sensor platform was selected as the optimum material for in-breath O(2) analysis due to its short response time, negligible humidity interference and suitable O(2) sensitivity in the relevant range in addition to its compatibility with a single-point calibration strategy. 相似文献