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11.
The Dunford-Pettis property is shown to hold for the uniformalgebra A() and its dual for some standard domains , includingstrongly pseudoconvex bounded domains in Cn, pseudoconvex boundeddomains of finite type in C2, and bounded domains in C. Previouslythe result was known for the unit ball and unit polydisc inCn. Techniques used involve Bourgain algebras, Hankel operators,properties of the Bergman kernel, quasi-metrics on the boundary,and -theory. 相似文献
12.
Le Faou JH Suomijärvi T Blumenfeld Y Piattelli P Agodi C Alamanos N Alba R Auger F Bellia G Chomaz P Coniglione R Del Zoppo A Finocchiaro P Frascaria N Gaardhoje JJ Garron JP Gillibert A Lamehi-Rachti M Liguori-Neto R Maiolino C Migneco E Russo G Roynette JC Santonocito D Sapienza P Scarpaci JA Smerzi A 《Physical review letters》1994,72(21):3321-3324
13.
14.
We present here an ab-initio STO-3G and advanced semiempirical AM1 calculation for the structure and the conformational behavior of phenyltetrazine and bitetrazine molecules. Results for phenyltetrazine isomers show that in the absence of H-H interactions, the preferred conformation is the planar one. Instead, in the case of bitetrazines, the systems dominated by the lone pair-lone pair interactions are not planar. In the presence of direct H-H interaction as for 5-5-1,2,3,4 bitetrazine, the antiplanar conformation is the preferred one. Comparison with other systems (including one or more nitrogen lone pairs) shows that the compounds with the same ortho substituents have very similar conformational behavior irrespective of their composition. The AM1 results indicate that this method is able to give reliable conformational information for compounds in which H-H interactions are involved. A Fourier expansion of the torsional potential suggests that the first two terms fit the calculated torsional potentials well except in the case of two H-H interactions in the same molecule. 相似文献
15.
16.
Coated capillaries modified with a hydrophobic layer were developed. Linear hydrocarbons and ethylbenzene modified surfaces greatly improved the electrophoretic performance of the capillaries. The column efficiency for organic compounds reached as high as 327 000 theoretical plate numbers per meter on a 50 microm I.D. linear hydrocarbon (C6) surface treated fused-silica capillary column. This value did not change during 50 repeated analyses and the columns showed strong stability against 0.1 M NaOH and 0.1 M HCl. The relative standard deviation of the run-to-run, day-to-day, and capillary-to-capillary coating with hydrophobic layer showed values of < or =2.5%, and good reproducibility. The separations of four aromatic amines and six pharmacological amines at pH 2.5 is reported. 相似文献
17.
Marialuisa Russo Gabriella Poggi Maria Luisa Navacchia Mila D'Angelantonio Salvatore S Emmi 《Research on Chemical Intermediates》2006,32(2):153-170
Chemical radiolytic oxidation induced by OH addition on 1-(2-furan-2-yl-5-hydroxy-6-hydroxymethyl-[1,3]dioxan-4-yl)-ethan-1,2-diol
(sorbitylfurfural, SF) leads, in the presence of controlled amounts of oxygen, to a permanent functional modification of the
target molecule. The yield of conversion reaches 60% of the starting material. LC-MS analysis allowed the identification,
as final products, of carboxylic acids, butenal and hydroxy-furan derivatives in which the sugar chain remains unbroken, while
the furanic ring is attacked first by OH and then by oxygen, giving in succession an intra-/inter-molecular rearrangement
of the allylperoxyl radicals thus formed. The proposed oxidation of the furanic ring envisages the peroxyl intermediates undergoing
mono- and/or bi-molecular reactions; a reaction path has been outlined and is reported here. The presence of unsaturated bonds
in the final products could provide a further site for radical scavenger activity. Therefore, the fast reaction with O2 and the rearrangement of the produced peroxyl radicals to species, which are likely to be effective OH-capturers, reinforces
the antioxidant ability of SF. 相似文献
18.
U Bernini R Reccia P Russo A Scala 《Journal of photochemistry and photobiology. B, Biology》1990,4(4):407-417
Quantitative photoacoustic spectra of the nuclei of cataractous human lenses with various degrees of colouration and opacification were measured in the spectral range 250-600 nm. The lens nuclei were obtained from 20 cataractous patients through extracapsular cataract extraction. These measurements yield the light loss per unit path length in the nucleus of cataractous lenses. 相似文献
19.
B. E. Krisyuk A. A. Popov G. E. Zaikov F. de Candia V. Vittoria R. Russo 《Colloid and polymer science》1987,265(3):220-225
The static modulus of elasticity (E) and the correlation time of rotation (
c
) of 2,-2,6,6-tetramethylpiperidine-1-oxyl are studied as a function of the temperature (210<T <350°K) for oriented films of isotactic polypropylene and polyethylene of high and low density.E and
c
change both upon heating and polymer orientation; this result indicates that sample properties are influenced by the microstructure of the amorphous phase where probes are localized. 相似文献
20.
C. Bagnasco P. Ciambelli S. Crescitelli G. Russo 《Reaction Kinetics and Catalysis Letters》1978,8(3):293-300
Cytalysts containing manganese, cobalt or nickel oxides supported on -alumina were physically characterized and tested for the oxidehydrogenation of ethylbenzene. The physical characterization shows surface spinel formation and/or metal oxide segregation for the systems cobalt-alumina and nickelalumina, but Mn2O3 segregation only for the manganese system. The catalytic activity data indicate a promoting effect of Mn2O3 and cobalt aluminate, while the presence of Co3O4 results in a lower activity.
, , -Al2O3, . / - , Mn2O3 . , Mn2O3 , Co3O4) .相似文献