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831.
Stanley L Boylan 《Journal of Mathematical Analysis and Applications》1976,56(3):529-547
A Fourier transform for sufficiently bounded and regular functionals on C([0, 1], R) is introduced, which interchanges multiplication and differentiation. We define convolutions and prove a convolution theorem. Finally, we use the transform to uniquely solve the Cauchy problem for second-order parabolic equations in function-space, where the coefficients depend only on t. 相似文献
832.
833.
834.
Edward C. Waymire Stanley C. Williams 《Transactions of the American Mathematical Society》1996,348(2):585-632
A multiplicative random cascade refers to a positive -martingale in the sense of Kahane on the ultrametric space A new approach to the study of multiplicative cascades is introduced. The methods apply broadly to the problems of: (i) non-degeneracy criterion, (ii) dimension spectra of carrying sets, and (iii) divergence of moments criterion. Specific applications are given to cascades generated by Markov and exchangeable processes, as well as to homogeneous independent cascades.
835.
Chemical reduction of small inorganic gases is accomplished using an electro-thermal plasma reactor. This benchscale reactor maintains a highly reactive plasma zone in a fluidized bed of carbon particles through which an electrical current is discharged. The carbon particles function as current-controlling media, heat sinks and reaction sites. Chemicals introduced into this medium are subjected to a variety of energy sources and chemically reactive species, which result in chemical reduction. It is shown that the inorganic gases, H2O, CO2, NO, NO2 and SO2, are chemically reduced in the plasma zone of the reactor. The end products consist of hydrogen, carbon monoxide and nitrogen gases. Additionally, elemental sulfur is deposited onto the carbon particles. 相似文献
836.
Eva Eichler C. Stanley Rooney Haydn W. R. Williams 《Journal of heterocyclic chemistry》1983,20(2):419-421
The preparations of some 4-pyridylimidazo[2,1-b]thiazole and -imidazo[5,1-b]thiazole derivatives are described. In some of the cyclizations to form the imidazothiazole ring systems, trifluoroacetic anhydride, the dehydration reagent employed, participated in the reaction leading to products bearing a trifluoromethyl or trifluoroacetyl substituent. 相似文献
837.
The open-circuit behavior of iodine films formed on platinum by electrooxidation of iodide was studied at rotating disk and rotating ring-disk electrodes. The potential transient and ring current transient at open circuit for cI?>0.012 M can be explained by assuming: (1) convective-diffusion controlled dissolution of the film; (2) establishment of the I2+I?→ I3? equilibrium; (3) establishment of the I2 (solid) →I2 (solution) equilibrium. The behavior at lower concentrations of cI? suggests that convective-diffusion control is absent. 相似文献
838.
Salvador Puig-Torres Gary E. Martin Steven B. Larson Stanley H. Simonsen 《Journal of heterocyclic chemistry》1984,21(1):155-159
Reaction of the dianion of 3-hydroxypyridine-2(1H)-thione with 5-chloro-4-nitro-1-methylimidazole in N,N-dimethylformamide led to the formation of 5-(3′-hydroxypyridyl-2′-thio)-4-nitro-1-methylimidazole, which failed to cyclize to the desired pyrid[1,4]oxathiinoimidazole derivative. In an effort to determine why the intermediate phenolate sulfide had failed to cyclize, the crystal structure of the isolated product was determined. The structure refined to R = 0.036. 相似文献
839.
The preparation and 1H NMR spectra of some di-μ-chloro-bis(N,N-dialkylbenzylamine-2,C,N)dipalladium(II) complexes, and the corresponding monomeric triphenylphosphine derivatives are described. A reaction sequence is presented for the cyclopalladation reaction and some improved conditions for the preparation of these complexes are presented. 相似文献
840.
The first systematic series of bismuth complexes involving ester donors, Bi(SCH(2)C(O)OCH(2)CH(3))Cl(2), Bi(SCH(2)C(O)OCH(3))(2)Cl, and Bi(SCH(2)COOCH(3))(3), has been isolated and characterized by spectroscopic (IR, Raman) and X-ray crystallographic data. In addition, these and other species have been identified by electron-impact, electrospray, and atmospheric pressure chemical ionization mass spectometry. The generally applicable synthetic methodology involves the use of heterobifunctional ligands containing a thiolate moiety as an anchor to facilitate coordinate interactions between weak donors (carbonyls) and weak acids (bismuth). The bifunctional nature of the ligands is manifested in both chelating and bridging roles. Important comparisons can be made with the pharmaceutical agent "colloidal bismuth subcitrate" (CBS). The observations allow for a new appreciation of bioactive bismuth compounds, by providing an approach to study the interaction of biorelevant functional groups with bismuth. 相似文献