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41.
Linear operators of the form are studied, where { n k } denotes the Haar system and n a permutation of the integers 1, 2, ..., 2 n . Conditions ensuring boundedness of these operators in the Lorentz spacesL p,q , and in particular inL p , are found.  相似文献   
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A synthetic route to 1-hydroxy- and 1-alkoxymethyl-3-polyfluoroalkylpyrazoles via regioselective N-hydroxy- and alkoxymethylation of N-unsubstituted pyrazoles with paraformaldehyde has been proposed. The alkoxyalkylation of polyfluoroalkylpyrazoles proceeds in aqueous-alcohol medium, whereas hydroxymethylation requires anhydrous conditions.  相似文献   
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We consider new methods of constructing differential bases. Symmetric spaces with essentially different fundamental functions at zero can be defined by means of differential bases. Even the Lorentz and Marcinkiewicz or the Lebesgue and Marcinkiewicz spaces can be defined by means of differential bases.  相似文献   
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LetE be a compact set inR n (n≧2), and denote byV 0(E) the number of the components ofE. Letp=1,2, ...,n?1;k=0,1, ...,p, and $$V_k (E;n,p) = \int\limits_{\Omega _k^n } {V_0 (E \cap \tau )^{{{(n - p)} \mathord{\left/ {\vphantom {{(n - p)} {(n - k)}}} \right. \kern-\nulldelimiterspace} {(n - k)}}} d\mu _\tau ,}$$ whereΩ k n is the set of all (n-k)-dimensional hyperplanesτ?R n and τ is the Haar measure on the spaceΩ k n ; furthermore, let $$V_n (E;n,n - 1) = mes_n E.$$ . Theorem. Let E?Rn, p=1, 2 ..., n?1, Vp+1(E;n,p)=0, and Vk(E; n, p)<∞ for k= =0,1, ..., p. Then the contingency of the set E at a point xE coincides with a certain p-dimensional hyperplane for almost all points xE in the sense of Hausdorff p-measure.  相似文献   
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A prompt activation technique – detection of the α-particles with surface barrier silicon and solid state track detectors, detection of the γ rays with (GeLi) detector – based on the 10B(n, α)7Li nuclear reaction was applied for boron determination using a time-of-flight technique on the IBR-30 pulsing reactor. The method was used for measurement of the boron concentration and distribution in bean and maize leaves.  相似文献   
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Using the method of metathesis polymerization carbon-chain homopolymers containing triрhenylsilyl, tritolylsilyl and trithienylsilyl groups in the side chains, as well as their copolymers with additional carbazole-containing units have been synthesized. Photophysical properties of the obtained compounds were investigated. All polymer products show an intense photoluminescence in the blue region of the spectrum. The largest quantum yield (61.4%) was shown by the copolymer with triphenylsilyl and carbazole side groups.  相似文献   
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