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31.
Christophe Cuny 《Journal of multivariate analysis》2006,97(8):1842-1869
Let (Xm,n)(m,n)∈Z2 be a Cp-valued wide sense stationary process. We study the prediction theory of such processes according to different total orders on Z2. In the case of a “rational order”, we give the spectral distribution of the resulting evanescent component and prove that for two different rational orders, the resulting evanescent components are mutually orthogonal. 相似文献
32.
S. Mathias M. Wessendorf S. Passlack M. Aeschlimann M. Bauer 《Applied Physics A: Materials Science & Processing》2006,82(3):439-445
Epitaxial ultra-thin Ag films grown on Cu(111) have been investigated by angle-resolved photoemission spectroscopy. The thickness
dependence of the binding energy for the Shockley surface state at 300 K could be determined accurately in films up to 5 ML
thick. Furthermore, we observe drastic changes in the film morphology after annealing to 450 K. Spectral modifications in
the shape of the quantum-well states (QWS), characteristic for these ultra-thin silver films, prove that the surface morphology
is homogeneous. The photoemission spectra also indicate that the silver film bifurcates to form a film exhibiting two distinct
film thicknesses. For all levels of silver coverage, we identify surface regions that are 2 ML thick, while the thickness
of the remaining surface depends on the amount of deposited silver. The almost purely Lorentzian line-shape of the spectral
features corresponding to the two different surface regions show that both surface areas are atomically flat.
PACS 68.55.Jk; 73.20.At; 73.21.Fg; 79.60.Dp 相似文献
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36.
The hydrogen-deuterium exchange of H-2 in 4-pyrimidone, a number of 1- and 3-alkyl-4-pyrimidones and several of their thione analogs in deuterium oxide at moderate temperatures is reported. This reaction is apparently not susceptible to acid or base catalysis. Cations of the 4-pyrimidones were found not to exchange H-2 at all in acid media. Catalytic amounts of bases do not alter the exchange rates whereas more concentrated alkali decompose the pyrimidone. However, 1,4(3,4)-dihydro-1,3-dimethyl-4-oxopyrimidinium iodide (and its 6-methyl analog) exchange H-2 quite rapidly in neutral deuterium oxide, almost instantly when triethylamine is added as a catalyst, and very slowly in dilute solutions of deuterium chloride in deuterium oxide. Mechanisms are proposed to account for these phenomena. 相似文献
37.
38.
I. Bauer 《Fresenius' Journal of Analytical Chemistry》1967,231(6):464
Ohne Zusammenfassung 相似文献
39.
Ohne Zusammenfassung7. Mitt.:Hermann Schmid undG. Bauer, Mh. Chem.96, 1508 (1965); dort ältere Mitt. dieser Reihe zitiert. 相似文献
40.
[structure: see text] 2,6-Disubstituted pyridines, 6-substituted 2,2'-bipyridines, and 6,6'-disubstituted 2,2'-bipyridines are readily prepared under mild conditions from 5-(dimethylamino)-1-naphthalenesulfonamide chloride (DANS-Cl) and chloromethyl-nitronyl nitroxide (CH(2)Cl-NIT) starting materials and adequately functionalized building blocks. The syntheses of the pyridine molecules bearing two radicals and a DANS fragment first required the attachment of the aliphatic radical onto an aldehyde-protected dansylated compound, followed by the construction of the second aromatic radical. 相似文献