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41.
Aequationes mathematicae - Given a probability space $$ (\Omega , {\mathcal {A}}, P) $$ , a complete and separable metric space X with the $$ \sigma $$ -algebra $$ {\mathcal {B}} $$ of all its... 相似文献
42.
Experimentally-determined permeation transients do not support the view that the behaviour of water in PDMS is significantly influenced by statistical-mechanical clustering; rather, they suggest that water behaves in a straightforward way. Simple calculations appear to confirm that the incidence of the statistical clustering of water in the polymer is negligible. A diffusion coefficient derived to include the influence of hydrophilic sites within the polymer is partially successful in mathematically reproducing measured quantities. An entropy calculation appears to suggest that the amount of mobile water in PDMS is solely thermally determined; hence the reduction of supposed hydrophilic impurities would probably not lead to a reduction in water permeation. The apparently large difference between the water solubility in PDMS, and that in siloxane liquids, a point of some interest in separation processes, remains unexplained in this paper. 相似文献
43.
W. Baron 《Archiv der Mathematik》1978,30(1):443-448
Ohne Zusammenfassung 相似文献
44.
S. Baron 《Israel Journal of Mathematics》1982,43(2):105-115
LetB be an arbitrary normal matrix, satisfying some conditions. AbsoluteB-summability factors in a sequence for Cesàro methodC
α if α≧1 or α=0 and absolute convergence factors in a sequence forC
α if 0<α<1 are obtained. 相似文献
45.
Abstract-o-Acylaminobenzylidenephosphoranes lead to indoles in good yield by an intramolecular Wittig reaction with the amide carbonyl group. Mechanistic aspects are discussed. A general method is described for the synthesis of indoles from o-nitrobenzyl bromides and o-aminobenzyl alcohols. 相似文献
46.
Single crystal structure studies at room temperature have been made for the first stage Mn Cl2 intercalated graphite. The nominal composition was C5·6 Mn Cl2·4, as deduced from chemical analyses and X-ray diffraction intensities. The data are in agreement with the island model, already proposed for Ni Cl2 intercalation. From the decrease in C-C bond length and comparison with As F5 compound, it is shown that the charge transfer is determined by chlorine in excess with respect to free metal halide. 相似文献
47.
Zayats M Katz E Baron R Willner I 《Journal of the American Chemical Society》2005,127(35):12400-12406
An electrically contacted glucose dehydrogenase (GDH) enzyme electrode is fabricated by the reconstitution of the apo-GDH on pyrroloquinoline quinone (PQQ)-functionalized Au nanoparticles (Au-NPs), 1.4 nm, associated with a Au electrode. The Au-NPs functionalized with a single amine group were attached to the Au surface by 1,4-benzenedithiol bridges, and PQQ was covalently linked to the Au-NPs. The apo-GDH was then reconstituted on the PQQ cofactor sites. The surface coverage of GDH corresponded to 1.4 x 10(-12) mol cm(-2). The reconstituted enzyme revealed direct electrical contact with the electrode surface, and the bioelectrocatalytic oxidation of glucose occurred with a turnover number of 11,800 s(-1). In contrast, a system that included the covalent attachment of GDH to the PQQ-Au-NPs monolayer in a random, nonaligned, configuration revealed lack of electrical communication between the enzyme and the electrode, albeit the enzyme existed in a bioactive structure. The bioelectrocatalytic function of the later system was, however, activated by the diffusional electron mediator 2,6-dichlorophenol-indophenol. The results imply that the alignment of GDH on a Au-NP through the reconstitution process leads to an electrically contacted enzyme-electrode, where the Au-NP acts as a charge-transfer mediator. 相似文献
48.
Ohne Zusammenfassung 相似文献
49.
50.
Using an impact parameter formulation, differential production probabilities for γγ dileptons in central relativistic heavy ion collisions at RHIC and LHC energies are calculated and compared to Drell-Yan and thermal ones. The angular distributions of the leptons give a handle for the discrimination. Nuclear stopping leads, apart from Bremsstrahlung pair production, to a modification of the pure γγ dilepton production. These modifications are studied in a simple model and are found to be of minor influence. 相似文献