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1.
Multilinear interpolation is a powerful tool used in obtaining strong-type boundedness for a variety of operators assuming only a finite set of restricted weak-type estimates. A typical situation occurs when one knows that a multilinear operator satisfies a weak Lq estimate for a single index q (which may be less than one) and that all the adjoints of the multilinear operator are of similar nature, and thus they also satisfy the same weak Lq estimate. Under this assumption, in this note we give a general multilinear interpolation theorem which allows one to obtain strong-type boundedness for the operator (and all of its adjoints) for a large set of exponents. The key point in the applications we discuss is that the interpolation theorem can handle the case q?1. When q>1, weak Lq has a predual, and such strong-type boundedness can be easily obtained by duality and multilinear interpolation (cf. Interpolation Spaces, An Introduction, Springer, New York, 1976; Math. Ann. 319 (2001) 151; in: Function Spaces and Applications (Lund, 1986), Lecture Notes in Mathematics, Vol. 1302, Springer, Berlin, New York, 1988; J. Amer. Math. Soc. 15 (2002) 469; Proc. Amer. Math. Soc. 21 (1969) 441). 相似文献
2.
Summary The synthesis of three vinylbenzyl complexes (n5-C5H5)-M(CO)n(CH2C6H4CH=CH2), [1), M=Mo, n=3; (2), M=W, n=3; (3), M=Fe, n=2] is reported. Complexes (1) and (2) have been copolymerized with monomers, such as styrene, methyl methacrylate, andN-vinyl-2-pyrrolidone, in benzene using azoisobutyronitrile as initiator. The rates of incorporation of (2) into copolymers with styrene and methyl methacrylate were the same as the rate of incorporation of the organic monomer. The homopolymerization of (2) was also carried out. Polymerizations occurred satisfactorily except for the copolymerization of (1) with styrene, where little incorporation of the organometallic monomer occurred. 相似文献
3.
The intensity dynamics of the double-clad Yb fibre laser have been characterised. Stabilisation of the fibre laser intensity by using uniform bi-directional pumping is demonstrated. For the single-end-pumped Yb fibre laser, the output becomes more stable for the shorter fibre length due to the higher threshold of stimulated Brillouin scattering, SBS, and Kerr effects and the reduction of saturated absorber effects caused by any unpumped fibre section. By additional pumping in a double-end-pumped configuration, the output power can be scaled higher before detecting high intensity pulses initiated by SBS in the Yb fibre laser due to the reduction of saturable absorption effect. It is confirmed that uniform pumping enhances the stability of the laser output. 相似文献
4.
Kochocki JA Allison WW Alner GJ Ambats I Ayres DS Balka LJ Barr GD Barrett WL Benjamin D Border P Brooks CB Cobb JH Cockerill DJ Coover K Courant H Dahlin B DasGupta U Dawson JW Edwards VW Fields TH Kirby-Gallagher LM Garcia-Garcia C Giles RH Goodman MC Heller K Heppelman S Hill N Hoftiezer JH Jankowski DJ Johns K Joyce T Kafka T Litchfield PJ Lopez FV Lowe M Mann WA Marshak ML May EN McMaster L Milburn RH Miller W Napier A Oliver WP Pearce GF Perkins DH Peterson EA Price LE Roback D Rosen DB 《Physical review D: Particles and fields》1990,42(9):2967-2973
5.
6.
Norman S. Allen Alfonso Chirinos-Padron John H. Appleyard Terence J. Henman 《Polymer Degradation and Stability》1983,5(2):105-112
The effect of calcium and nickel stearates on the photo-stabilising action and photo-decomposition of one calcium and two nickel metal chelates in polypropylene has been examined using infra-red and ultraviolet derivative spectroscopy. Whereas the presence of calcium stearate antagonises the photo-stabilising action of one nickel chelate, Irgastab 2002, it strongly synergises with the other, Cyasorb UV 1084. The presence of nickel stearate synergises with the calcium chelate, Irganox 1425, in unprocessed polymer whereas, in processed polymer, it exhibits antagonism. Rates of photo-decomposition of the metal chelates are also affected by metal stearates. The data suggests that, with these nickel chelates, there might be some degree of metal exchange with certain metal stearates. 相似文献
7.
Dynamic light scattering has been used to determine the hydrodynamic thickness of poly(ethylene oxide) (PEO) adsorbed on synthetic anisotropic clay particles (Laponite) as a function of molecular weight. The layer thicknesses, and their increase with molecular weight, indicate that the conformation of the adsorbed layer is very compact and is much smaller than those normally observed for polymer adsorption on flat interfaces. The aggregation kinetics of the polymer coated particles in 5 mM NaCl was analyzed in a quantitative manner, revealing that the potential barrier to aggregation is strongly enhanced when polymer is present. 相似文献
8.
Emmanuelle A. BugnetTracy D. Nixon Colin A. KilnerRobert Greatrex Terence P. Kee 《Tetrahedron letters》2003,44(29):5491-5494
Molecular clips derived from 2,4,6,8-tetraazabicyclo[3.3.1]nonane-3,7-dione promote increased regioselectivity in the SO2Cl2-mediated electrophilic aromatic chlorination of ortho-cresol leading to para/ortho ratios (Rp/o) <25; approximately six times larger than in the absence of the clip. Specific recognition events involving hydrogen-bond, π-π and dative covalent interactions are implicated. 相似文献
9.
A number of novel 3-aminoquinazolines were obtained via two synthetic pathways. In the first method o-aminobenzoylhydrazines were prepared either by reacting an isatoic anhydride and a hydrazine or by reacting o-nitrobenzoic acid with a hydrazine, followed by catalytic reduction. Subsequent cyclization with an appropriate orthoester provided 3-aminoquinazolines and 2-methyl-3-aminoquinazolines. The second pathway involved condensation of o-aminoacetophenone with a hydrazine to form hydrazones which were reduced to aminohydrazines and cyclized as above to yield 4-methyl-3-aminoquinazolines and 2,4-dimethyl-3-aminoquinazolines. The title compounds were evaluated in mice in MES and sc Met seizure models for anticonvulsant activity, and in the rotorod test for neurotoxicity. They were generally toxic. However, 4-methyl-3-(N-piperidino)-3,4-dihydroquinazoline hydrochloride exhibited activity comparable to that of methaqualone. 相似文献
10.
Fry FH Holme AL Giles NM Giles GI Collins C Holt K Pariagh S Gelbrich T Hursthouse MB Gutowski NJ Jacob C 《Organic & biomolecular chemistry》2005,3(14):2579-2587
Certain cancer cells proliferate under conditions of oxidative stress (OS) and might therefore be selectively targeted by redox catalysts. Among these catalysts, compounds containing a chalcogen and a quinone redox centre are particularly well suited to respond to the presence of OS. These catalysts combine the specific electrochemical features of quinones and chalcogens. They exhibit high selectivity and efficiency against oxidatively stressed rat PC12, human Jurkat and human Daudi cells in cell culture, where their mode of action most likely involves the catalytic activation of existent and the generation of new reactive oxygen species. The high efficiency and selectivity shown by these catalysts makes them interesting for the development of anti-cancer drugs. 相似文献