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1.
Methylcyanide, CH3CN, is an important interstellar species, and therefore the accurate knowledge of precise rest frequencies for rotational transitions as well as ground-state rotational and hyperfine constants is needed. In this work the hyperfine structure of the millimeter- and submillimeter-wave spectra of CH3CN has been further investigated. In addition, accurate THz measurements have been carried out for the first time. Consequently, the present investigation allowed us to provide the most accurate ground state rotational and hyperfine parameters known at the moment for CH3C14N. To resolve the hyperfine structure of the rotational transitions observed, the Lamb-dip technique has been exploited. Both frequency-modulated and video-type detections have been employed. 相似文献
2.
Gabriele Bonanno 《Journal of Global Optimization》1998,12(1):101-104
In this note we introduce a suitable class of functionals, including the class of integral functionals, and prove that any (strict) local minimum of a functional of this class, defined on a decomposable space, is a (strict) global minimum. So, the recent result obtained by Giner in [1] is specified and extended. 相似文献
3.
Stephan Dahlke Gabriele Steidl Gerd Teschke 《Journal of Fourier Analysis and Applications》2004,10(5):507-539
This article is concerned with frame constructions on domains and manifolds. The
starting point is a unitary group representation which is square integrable modulo a suitable
subgroup and therefore gives rise to a generalized continuous wavelet transform. Then generalized
coorbit spaces can be defined by collecting all functions for which this wavelet transform
is contained in a weighted Lp-space. Moreover, we show that a judicious discretization of the
representation leads to an atomic decomposition and to Banach frames for these coorbit spaces. 相似文献
4.
5.
Säurekatalysierte Umlagerungen von 1,5-Dimethyl-6-methyliden-tricyclo[3.2.1.02,7]oct-3-en-8endo-olen
Gabriele Mukherjee-Müller Paul Gilgen Janos Zsindely Hans Schmid 《Helvetica chimica acta》1977,60(5):1758-1780
Acid Catalysed Rearrangement of 1,5-Dimethyl-6-methyliden-tricyclo[3.2.1.02,7]oct-3-en-8endo-ols The tricyclic alcohols 2,3,4 and 6 (Scheme 1) are synthesized by the reaction of the tricyclic ketone 1 with sodiumborohydrid or metalloorganic reagents. Their configuration at C(8) is determined by NMR. in the presence of Eu(fod)3. The exo-attack of 1 by the nucleophil forming the endo-alcohol is favored, the π-electrons of C(3) = C(4) hindering the endo-attack. On treatment with sulfuric acid in dioxane/water at 25° the tertiary alcohols yield aryl-substituted ketones. 3 gives in 78.5% yield a mixture of the 3-(dimethylphenyl)-2-butanones 12 and 13 , in addition to 16.5% of (2,3,4-trimethylphenyl)-2-propanon ( 14 ) (Scheme 2). The alcohols 4 and 6 yield mixtures of the 2-(dimethylphenyl)-3-pentanones 19 and 20 (72%), and 2-(dimethylphenyl)-propiophenones 21 and 22 (68%), respectively (Scheme 2). In the case of the secondary alcohol 2 mainly products derived from hydration at the C(6), C(9) double bond are formed, namely the mixture of diols 23 and 24 (21%), and the mixture of the isomeric 2-(dimethylphenyl)propanals 25, 26 and 27 (3%) (Scheme 3). - The structures of 12–14, 19/20, 21/22, 23/24 and 25/26/27 were established by spectroscopic data. In the case of 12 and 13 the degradation of their mixture to the known 1-(dimethylphenyl)ethanols 17/18 confirmed the assignment. - The most probable mechanism for the rearrangement of 3 is shown in Schemes 4 and 5. The reaction proceeds from 3 through a, b and g to 12 and 13; 14 is formed via e, f and i . In the case of 4 and 6 only the reaction analogue to 3 → a → b → g ?12/13 takes place. The isomeric aldehyds 25–27 formed from 2 could have the structures s, t , and v . The former two could be generated in a similar way as 12/13 from 3 , the latter one as shown in Scheme 8. 相似文献
6.
An enzyme inhibition biosensor, developed in our laboratory and previously used for the analysis of compounds with anticholinesterase activity (e.g. physostigmine, neostigmine, pyridostigmine nicotine and organophosphorus compounds) has now been tested for the analysis of another recently synthesized cholinesterase inhibitor, i.e. eptastigmine. In addition nicotinic acid and nicotinamide, although displaying weaker inhibition properties, were also tested in pharmaceutical products using the same inhibition enzyme sensor. The biosensor consisted of a hydrogen peroxide amperometric electrode coupled to a functionalised nylon membrane chemically bonding both the enzymes butyrylcholinesterase and choline oxidase; a butyrylcholine standard solution in glycine buffer acted as substrate. The response of the system to all the inhibitors considered was characterised completely and the analysis of several pharmaceutical formulations containing nicotinamide or nicotinic acid was also performed. 相似文献
7.
Gabriele H. Greco 《Annali di Matematica Pura ed Applicata》1984,137(1):61-81
Summary
Sequential forms of De Giorgi's -limits are obtained via a decomposition of their carriers (carrier=sostegno) in the setting of completely distributive complete lattices. Moreover, the notion of carrier enables us to calculate easily the K-limits of epi- or hipo-graphs of arbitrary -limits. 相似文献
8.
Gabriele H. Greco 《Annali dell'Universita di Ferrara》1981,27(1):13-19
Riassunto In questo articolo si danno delle condizioni necessarie e sufficienti affinchè per una fissata coppia di funzioni d’insieme
ν, μ crescenti esista una funzionef tale che ν=∫fdμ. Si ottiene cosi una proposizione comprendente il teorema di R-N. classico e dei teoremi di R-N., presentati da altri autori,
riguardanti le funzioni d’insieme finitamente additive e le funzioni d’insieme subadditive e continue per successioni crescenti.
Résumé Soient ν, μ:A→[0,+∞) deux fonctions d’ensemble croissantes sur une σ-algèbre d’ensemblesA⊂T(X), telles que pour chaqueA∈A avec ν(A)=μ(A)=0 on a l’égalité μ(A)=μ(A∪S) ∀S∈A (c’est le cas des fonctions sousadditives!). Dans cet article on démontre qu’il existe une fonctionf A-measurable telle que ν=∫fdμ si et seulement si pour chaquer∈(0, + ∞) il y a un ensembleA r∈A qui vérifie les trois conditions suivantes: (1) ,B∈A avecB⊂A; (2) A (3) limν(A r)=0. On déduit ainsi une proposition qui a été donnée parI. Forana: ?Si ν, μ sont simplement additives, il existe une fonctionf telle que ν=∫fdμ si et seulement si ν≪μ et la fonction d’ensemble additive a une decomposition de Hahn pour chaquer∈(0, + ∞), c’est-á-dire il y aA r∈A tel que ?.相似文献
9.
10.
The Armstrong model of the Schuknecht gel foam and wire prosthesis was tested in the magnetic field of a 1.5 Tesla magnet. The wire component of the prosthesis was found to be non-magnetic. Patients with this prosthesis can therefore undergo MRI examination safely. Two previous articles from the non radiologic literature concerning the magnetic properties of metallic middle ear prostheses are reviewed. 相似文献