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101.
Ernestina Muñoz Ignacio Tejera Rafael Jiménez Francisco Sánchez 《Reaction Kinetics and Catalysis Letters》1991,43(1):163-167
The kinetics of solvolysis of t-butyl chloride in water-glucose and water-sucrose solutions have been studied. From the data obtained, Y Grunwald-Winstein parameters corresponding to these mixtures have been derived.
- . Y - .相似文献
102.
Let {S
k
, k ≥ 0} be a symmetric random walk on , and an independent random field of centered i.i.d. random variables with tail decay . We consider a random walk in random scenery, that is . We present asymptotics for the probability, over both randomness, that {X
n
> n
β} for β > 1/2 and α > 1. To obtain such asymptotics, we establish large deviations estimates for the self-intersection local
times process , where l
n
(x) is the number of visits of site x up to time n.
相似文献
103.
G. Ouedraogo P. Morliere M. Bazin R. Santus† B. Kratzer M. A. Miranda J. V. Castell 《Photochemistry and photobiology》1999,70(2):123-129
The fluoroquinolone antibiotics are widely used despite their strong phototoxicity under solar UV irradiation. Although they are known as good photodynamic photosensitizers, other factors than production of activated oxygen species may play a role in the effectiveness of the phototoxic effect. Subcellular localization is one of the important parameters that may determine this strength. Using microspectrofluorometry, it is shown that norfloxacin, ofloxacin, lomefloxacin, ciproflaxin and BAYy3118 are readily incorporated into lysosomes of HS68 human skin fibroblasts although weak staining of the whole cytoplasm also occurs especially with norfloxacin. Consistent with their photoinstability in solutions, the fluoroquinolones under study are readily photobleached by UVA in the HS68 fibroblasts. The BAYy3118 derivative that has the fastest bleaching rate also shows the strongest phototoxicity toward HS68 fibroblasts. Photosensitization with these fluoroquinolones induces lysosomal membrane damage as shown by the increased rate of leakage of the lysosomal probe lucifer yellow as compared to that observed with untreated cells. 相似文献
104.
105.
106.
Moisés Cabo Eva Pellicer Emma Rossinyol Pau Solsona Onofre Castell Santiago Suriñach Maria Dolors Baró 《Journal of nanoparticle research》2011,13(9):3671-3681
The synthesis of NiCo2O4 spinel by several nanocasting strategies (i.e., multi-step nanocasting, one-step nanocasting and soft-templating), in which
nickel and cobalt nitrates are used as precursors and Pluronic P123 as surfactant, is explored. First, in the multi-step nanocasting,
the effect of the impregnation method (evaporation, solid–liquid and two-solvent) of the SBA-15 silica template on the morphology
of NiCo2O4 replica is investigated. The evaporation method seems to be the best choice to obtain mesoporous NiCo2O4 powder which, after calcination at 375 °C and subsequent template removal, displays the highest surface area (93.1 m2/g). We have also checked the feasibility of the one-step nanoscating approach for the synthesis of ordered NiCo2O4 arrays, though this methodology entails severe difficulties, mainly related to the different decomposition temperature of
the nitrate precursors and the P123 surfactant. Finally, randomly oriented, aggregated NiCo2O4 nanoparticles are obtained by means of P123 surfactant-assisted soft-templating approach. 相似文献
107.
Pere Castell Angels Serra Marina Gali 《Journal of polymer science. Part A, Polymer chemistry》2004,42(14):3631-3643
A new series of liquid‐crystalline epoxy resins was synthesized, and their mesomorphic behavior was investigated with differential scanning calorimetry, polarized optical microscopy, and wide‐angle X‐ray scattering. These glycidylic compounds had central aromatic imine mesogens derived from benzidine and aliphatic spacers of up to 10 methylene units that linked the mesogens to the glycidylic groups. Crosslinking these monomers with primary aromatic diamines led to nematic networks, some of which contained crystal inclusions. However, through curing with tertiary amines as catalytic agents or through copolymerization with different proportions of the nonmesomorphic epoxy monomer and primary amines as crosslinking agents, smectic C organized thermosets were prepared when the spacers had at least four methylene carbons. When they had fewer than four, the networks were nematic. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3631–3643, 2004 相似文献
108.
Functionalizations of Mixtures of Regioisomeric Aryllithium Compounds by Selective Trapping with Dichlorozirconocene
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M. Sc. Alicia Castelló‐Micó Dr. Simon A. Herbert Dr. Thierry León Prof. Dr. Thomas Bein Prof. Dr. Paul Knochel 《Angewandte Chemie (International ed. in English)》2016,55(1):401-404
The reaction of mixtures of aryllithium regioisomers obtained either by directed lithiation or by Br/Li exchange with substoichiometric amounts of Cp2ZrCl2 proceeds with high regioselectivity. The least sterically hindered regioisomeric aryllithium is selectively transmetalated to the corresponding arylzirconium species leaving the more hindered aryllithium ready for various reactions with electrophiles. As an application, these regioselective transmetalations from Li to Zr were used to prepare all three lithiated regioisomers of 1,3‐bis(trifluoromethyl)benzene. 相似文献
109.
Silly F Shaw AQ Porfyrakis K Warner JH Watt AA Castell MR Umemoto H Akachi T Shinohara H Briggs GA 《Chemical communications (Cambridge, England)》2008,(38):4616-4618
A supramolecular grating of single Lu@C(82) molecules was obtained by depositing Lu@C(82) molecules onto a room temperature PTCDI-melamine network. 相似文献
110.
Wolfgang zu Castell Noemí Laín Fernández Yuan Xu 《Advances in Computational Mathematics》2007,26(1-3):155-171
The problem of interpolation at (n+1)2 points on the unit sphere
by spherical polynomials of degree at most n is proved to have a unique solution for several sets of points. The points are located on a number of circles on the sphere
with even number of points on each circle. The proof is based on a method of factorization of polynomials.
Dedicated to Mariano Gasca on the occasion of his 60th birthday
The second author was supported by the Graduate Program Applied Algorithmic Mathematics of the Munich University of Technology. The work of the third author was supported in part by the National Science Foundation
under Grant DMS-0201669. 相似文献