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151.
Leopoldo Nachbin 《Results in Mathematics》1985,8(2):117-122
If E is a complex (DFC)-space (see § 2), we show that E leads to pure uniform holomorphy (see §2) if and only if its Fréchet dual space E′ is separable (see Theorem 1, where these two conditions have other eight equivalent ones). By using a theorem of Mujica (see §4), we consider the (DFC)-space K(K) of germs around K of holomorphic C-valued functions where K is a nonvoid compact subset of a complex metrizable locally convex space E, and ?(K) is endowed with the topology ?0 obtained as an inductive limit of compact-open topologies (see §4). Not only Theorem 1 applies to ?(K), with E replaced by ?(K) in its statement, but also ?(K) leads to pure uniform holomorphy if and only if E is separable (see Theorem 2). 相似文献
152.
We have developed a flexible and thoroughly tested computer program for microscopic calculations of proton-induced pion production in nuclei at bombarding energies up to 500 MeV. The model used includes explicitly both the one-nucleon (pionic stripping) mechanism and the resonant p-wave rescattering part of the two-nucleon mechanism. Initial and final state interactions are included through proton-nucleus and pion-nucleus optical model distortions, with careful consideration of the multiple scattering series. The intermediate delta in the two-nucleon mechanism is treated as static with possible inclusion of a local density approximation for the delta-nucleus interaction. We explain the philosophy of the model, detail the parametrization of the microscopic dynamics, and give the formalism for the calculation of experimental observables. We also describe the testing of the computer program and present preliminary results for the 3He(p, π+)4He reaction. 相似文献
153.
G.P. Gambaretto M. Napoli L. Conte A. Scipioni R. Armelli 《Journal of fluorine chemistry》1985,27(2):149-155
Data in support of the four-stage mechanism ECbECN result from the electrochemical fluorination of some acyl halides (benzoyl, n-butyryl and iso-butyryl, benzenesulphonyl and p-toluenesulphonyl chlorides) and amines (tripropylamine and N-methylmorpholine). 相似文献
154.
The total synthesis of the naturally occurring kinase inhibitor pyridovericin 1 is reported. A flexible and efficient synthesis has been accomplished in good yield from readily available 2,4-dihydroxypyridine. Pyridovericin is a key intermediate in our proposed biomimetic synthesis of pyridomacrolidin 2. 相似文献
155.
Leopoldo Cortez 《Mikrochimica acta》1995,119(3-4):323-328
This paper presents one of the future trends in analytical quality assurance, the evaluation of the quality of analytical results by estimation of their uncertainties. The present state-of-the-art is described, and the impact caused by the declaration of uncertainties in chemical results is foreseen. 相似文献
156.
Maria de Fátima V Marques Carla C Pombo Rodrigo A Silva Anunciata Conte 《European Polymer Journal》2003,39(3):561-567
The binary silica supported catalyst system comprising the Cp2ZrCl2 and SiMe2(Ind)2ZrCl2 metallocene compounds was prepared with different immobilization methods and evaluated at different propylene polymerization conditions. The performance results of the homogeneous isolated catalysts and also the homogeneous catalyst mixture were also included for comparison. High activities were obtained with the supported systems and the molecular weight of the produced polypropylene was invariably higher than that obtained using the homogeneous precursor. 相似文献
157.
J. L. Jauberteau D. Conte M. I. Baraton P. Quintard J. Aubreton A. Catherinot 《Plasma Chemistry and Plasma Processing》1990,10(3):401-417
Silicon nitride thin films are deposited on silicon wafers at room temperature when silane gas is injected in a nitrogen flowing post-discharge. Reactive processes involving siane molecules and long-lifetime nitrogen species are studied, pointing out the nonreactivity of the N2(A3
u
+
) metastable state, the low contribution of the vibrationally excited nitrogen ground-state molecules, and the high reactivity of N(4S) atoms. Spectroscopic observations performed in the reaction region are correlated with thin-film characteristics. 相似文献
158.
Perfluoroalkanesulfonylimides and their lithium salts: synthesis and characterisation of intermediates and target compounds 总被引:1,自引:0,他引:1
Lino Conte Gerardo Caporiccio Fabrizio Alessandrini 《Journal of fluorine chemistry》2004,125(2):243-252
ECF processes have been extensively experienced and developed since early 1970s at the Fluorine Chemistry Laboratory of Padua University: several classes of perfluorinated inert and functional compounds have been obtained, in particular perfluoro heterocyclics and perfluorinated acid fluorides.Recently the demand for electrolyte salts, applied in lithium batteries, drove our interest to investigate on the perfluoroalkanesulfonylimides.A series of the perfluoroalkanesulfonylfluoride precursors has been obtained by ECF and their metathesis to the related imides and lithium salts has been investigated.A number of representative products has been obtained and characterized in their structure and ionic conductivity. 相似文献
159.
160.
An application that highlights the usefulness of a solid phase extraction sorbent having a removable surfactant "stationary phase" is introduced. Polyaromatic hydrocarbons (PAHs) efficiently trap on commercially available non-polar sorbents (i.e., C(18) silica). However, solvents that are necessary to break strong hydrophobic interactions between the analyte and sorbent are harmful and incompatible for direct introduction into a reversed phase liquid chromatographic setup. In the presented approach, the entire "stationary phase"-analyte association is removed, resulting in very efficient elutions with a final extract that is mild and reversed phase liquid chromatographic compatible. Commercial C(18) silica was placed adjacent to this sorbent to provide more efficient trapping of less hydrophobic PAHs. PAHs were preconcentrated from river water and were determined using fluorescence detection coupled to HPLC. Detection limits for all PAHs examined were in the sub [micro sign]g L(-1) level. 相似文献