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781.
Arduini A Demuru D Pochini A Secchi A 《Chemical communications (Cambridge, England)》2005,(5):645-647
Calix[4]arene derivatives supported on monolayer protected gold clusters show a remarkable enhanced binding efficiency towards quaternary ammonium salts in homogeneous solution of apolar solvents with respect to the corresponding unsupported hosts. 相似文献
782.
Moschetto G Lauceri R Gulino FG Sciotto D Purrello R 《Journal of the American Chemical Society》2002,124(49):14536-14537
This unprecedented calixarene templated, noncovalent synthesis of multi-porphyrin complexes in aqueous solution makes it possible to plan the nature, stoichiometry, and sequence of porphyrins. The proposed method presents the same accuracy of the covalent approach and a 100% yield, but it is not as time-consuming as the latter method. 相似文献
783.
We explore compactly supported scaling functions of wavelet theory by means of classical umbral calculus as reformulated by
Rota and Taylor. We set a theory of orthonormal scaling umbra which leads to a very simple and elementary proof of Lawton's
theorem for umbrae. When umbrae come from a wavelet setting, we recover the usual Lawton condition
for the orthonormality of the integer translates of a scaling function. 相似文献
784.
785.
In this paper we characterize the family of external lines to a hyperbolic quadric of PG
(3, q). 相似文献
786.
Mario De Salvo Domenico Freni Giovanni Lo Faro 《Rendiconti del Circolo Matematico di Palermo》1997,46(1):29-51
In this paper one continues the study of hypergroups with for proper pairs. In particular one considers the case when the
scalars group is not empty and the set of non-scalar elements has size two or three.
This work is produced by support of the Italian M.U.R.S.T. (quota 40%). No version of this paper will be published elsewhere. 相似文献
787.
Vincenzo Frenna Nicol
Vivona Domenico Spinelli Giovanni Consiglio 《Journal of heterocyclic chemistry》1980,17(5):861-864
The kinetic behaviour of the geometrical isomers I-E and I-Z of the title compound in the presence of piperidine in benzene has been investigated. The kinetic results suggest that I-Z rearranges directly into 2,5-diphenyl-4-benzoylamino-1,2,3-triazole (II), whereas I-E probably rearranges only through the intermediate I-Z formed by isomerization. All the reactions studied are piperidine-catalyzed. 相似文献
788.
789.
Problems of synchronization in special relativity and possible links with stochastic electrodynamics
The Mansouri-Sexl and Sjödin point of view on clock synchronization in special relativity is maintained against various criticisms, taking into account also the recent point of view of stochastic electrodynamics. Light speed invariance is also discussed in an intuitive way. 相似文献
790.
Domenico Zambella 《Mathematical Logic Quarterly》1997,43(3):401-412
We present a simple and completely model-theoretical proof of a strengthening of a theorem of Ajtai: The independence of the pigeonhole principle from IΔ0(R). With regard to strength, the theorem proved here corresponds to the complexity/proof-theoretical results of [10] and [14], but a different combinatorics is used. Techniques inspired by Razborov [11] replace those derived from Håstad [8]. This leads to a much shorter and very direct construction. 相似文献