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11.
Othman Belhadj Miled David Grosso Jacques Livage 《Journal of Physics and Chemistry of Solids》2004,65(10):1751-1755
This paper describes the synthesis and optical pH sensing properties of a pH indicator dye activated mesostructured silica coated optical fibre. The pH-sensitive dye bromothymol blue was incorporated into the mesostructure sol precursor and thin films/coatings were used for pH-sensing applications without prior removal of the surfactant. The pH sensitivity range and operating wavelength were analysed by absorption measurements on layer dip-coated on glass slides. The pH sensing properties of coated optical fibre were tested by evanescent wave method. Experiments were carried out by using a series of solutions of known pH. No leaching was observed (except at very high pH) and an excellent reversibility was obtained between pH=2 and 5. 相似文献
12.
Jacques Rouzaud MatthewD. Jones Robert Raja BrianF.G. Johnson John MeurigThomas MelindaJ. Duer 《Helvetica chimica acta》2003,86(5):1753-1759
A set of new, air‐stable, RhI‐based heterogeneous asymmetric hydrogenation catalysts have been synthesised, characterised, and tested. Individual members of this new family all exhibit good enantioselectivity. 相似文献
13.
Let X be a locally self-similar stochastic process of index 0<H<1 whose sample paths are a.s. CH?ε for all ε>0. Then the Hausdorff dimension of the graph of X is a.s. 2?H. To cite this article: A. Benassi et al., C. R. Acad. Sci. Paris, Ser. I 336 (2003). 相似文献
14.
We introduce new classes of 2-weight cyclic codes which are direct sums of 1-weight irreducible cyclic codes
相似文献
15.
A palladium‐TPPTS catalyst heterogenized on KF/alumina has been shown to be effective and recyclable for the selective formation of monooctadienylxylopyranosides via the telomerization of butadiene with D ‐xylose. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
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In this paper the performance of a fiber-optic LAN with spread spectrum multiplexing is discussed from the viewpoint of transmission parameters. Two architectures are considered. The first concerns a structure with cascade-connected Y-type fiber-optic couplers. The second concerns an architecture with cascade-connected active optoelectronic repeater-coupler (ORCA) devices. 相似文献
19.
Jacques Bros 《Communications in Mathematical Physics》2003,237(1-2):289-308
It is proved that in any massive relativistic quantum field theory satisfying two-particle asymptotic completeness, all the
bounded energy components in the elastic two-particle range of all subsets of states which are excitations of the vacuum state
by uniformly bounded observables localized in a given finite region of spacetime are compact in the Hilbert space of states.
This result, which is in agreement with Haag-Swieca's conjecture, is also given a more precise form in terms of the rate of
decrease of the ``N–dimensional thickness' (or approximation number) of such sets of states when N tends to infinity. A similar computation, valid at arbitrarily high energies, is also given for the massive free-field case.
Received: 7 February 2003 / Accepted: 5 April 2003
Published online: 13 May 2003
Communicated by H. Araki, D. Buchholz and K. Fredenhagen 相似文献