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Evi Honegger Edgar Heilbronner Kenneth B. Wiberg 《Journal of Electron Spectroscopy and Related Phenomena》1983,31(3):369-381
The electronic structure of the title compound (1) has been investigated using He(Iα) PE spectroscopy and assuming the validity of Koopmans' theorem. It is found that: (a) in analogy to the situation prevailing in the cyclophanes, hyperconjugation of the out-of-phase linear combination of the π-orbitals with the ethano-bridge σ orbitals is symmetry-forbidden; (b) in agreement with the ideas developed in Part I of this series [1], the strong local B1u-type bending of the ethylene moieties does not affect their basis energy significantly; and (c) the “through-space” coupling of the two double-bond π orbitals is of the same order as the benzene π-orbital coupling in [2n] cyclophanes, even if the net contribution to the repulsion of the two double bonds is probably small. Because of the near degeneracy of the HOMO and HOMO — 1 of 1, the ground state of the radical cation 1+ cannot be determined uniquely: it is either2Ag or2B1u. 相似文献
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For an arbitrary (possibly infinite-dimensional) pre-symplectic test function
space
the family of Weyl algebras
, introduced in a previous work [1], is shown to constitute a continuous field of C*-algebras in the sense
of Dixmier. Various Poisson algebras, given as abstract (Fréchet-) *-algebras which
are C*-norm-dense in
, are constructed as domains for a Weyl quantization,
which maps the classical onto the quantum mechanical Weyl elements. This kind
of a quantization map is demonstrated to realize a continuous strict deformation
quantization in the sense of Rieffel and Landsman. The quantization is proved to
be equivariant under the automorphic actions of the full affine symplectic group.
The relationship to formal field quantization in theoretical physics is discussed by
suggesting a representation dependent direct field quantization in mathematically
concise terms.
Communicated by Joel FeldmanSubmitted 07/10/03, accepted 07/11/03 相似文献
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Claudio Storck Raphael Gehrer Claude Fischer Markus Wolfensberger Flurin Honegger Gerhard Friedrich Markus Gugatschka 《Journal of voice》2011,25(5):632-637
Objectives/Hypothesis
Cricothyroid approximation (CTA) surgery aims at raising the voice pitch in male-to-female transsexuals. However, 30% of the patients are not satisfied with the result. The purpose of our study was to examine the cricothyroid joint (CTJ) biomechanics and to analyze if (and how) the CTJ anatomy influences the movement of the cricoid and, consequently, the elongation of the vocal fold and the voice pitch after CTA.Methods
Twenty-four cadaver larynges were examined with high-resolution computerized tomography and MIMICS three-dimensional imaging software (Materialise Interactive Medical Image Control System, Leuven, Belgium). After superimposing the two scans taken in “neutral” and in “CTA” positions, vector geometrical analysis was used to determine the effective rotation axis of the CTJ and to calculate the elongation of the vocal folds after CTA.Results
Our results showed that the cricoid rotates around an axis, the position of which depends on the anatomical structure of the CTJ. Based on the location of this effective rotation axis, we could distinguish three groups. In group I (N = 13), the rotation axis was located in the lower third; in group II (N = 5), it was located in the middle third; and in group III (N = 6), it was located in the upper third of the cricoid. The elongations of the vocal fold were 12%, 8%, and 3%, in groups I, II, and III, respectively.Conclusions
The anatomical structure of the CTJ influences directly (1) the position of the effective rotation axis and (2) the elongation of the vocal folds. 相似文献16.
Evi Honegger Philip E. Eaton B. K. Ravi Shankar Edgar Heilbronner 《Helvetica chimica acta》1982,65(7):1982-1989
The photoelectron (PE.) spectrum of the title compound has been assigned by comparison with the PE. spectrum of cubane ( 2 ), aided by ab initio STO-3G calculations using localized molecular orbitals. On the basis of the information available to date, the most satisfactory orbital sequence, Koopmans theorem implied, is, in descending order of energy: band system : (2e″2, 3e′2 2e″1, 3e′1); band system : 3a′1 (2e′2, 2a″2); band : 2e′1.(Sequence of orbitals in parenthesis uncertain). 相似文献
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Karl Rser Pierre-Alain Carrupt Pierre Vogel Evi Honegger Edgar Heilbronner 《Helvetica chimica acta》1990,73(1):1-12
Controlled ozonolysis of 2,3,5,6-tetramethylidene-7-oxabicyclo[2.2.1]heptane ( 1 ) afforded 3,5,6-trimethylidene-7-oxabicyclo[2.2.1]heptan-2-one ( 2 ). Ozonolysis of 2 gave a 1:1 mixture of 3,5-dimethylidene-7-oxa-bicyclo[2.2.1]heptane-2,6-dione ( 3 ) and 3,6-dimethylidene-7-oxabicyclo[2.2.1]heptane-2,5-dione ( 4 ). The He(Iα) photoelectron (PE) spectra of 2 and 4 have been recorded. Comparison with the PE data of related systems, and with the result of ab initio STO-3G calculations, confirm the existence of significant through-bond interactions between the oxygen lone-pair orbitals n(CO) of the carbonyl functions and n(O) of the O(7) ether bridge. 相似文献
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J. Gerum J. Fiehe W. Kordatzki Th. v. Fellenberg Paula Honegger und H. Barsch 《Fresenius' Journal of Analytical Chemistry》1929,77(5-6):232-233
Ohne Zusammenfassung 相似文献
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An automated high-performance liquid chromatographic method with electrochemical and fluorimetric detection and on-line data evaluation is described for the simultaneous measurement of indoleaminergic and catecholaminergic neurotransmitters, some of their metabolites and precursors and ascorbic and uric acids. Deproteinized tissue extracts from the central nervous system or peripheral organs are injected without prior purification (recovery greater than 90%). A switching system enables the compounds to be passed as necessary through one, two or three reversed-phase columns, which are then eluted simultaneously (analysis time 25 min). Fifty samples per day can be analysed with a precision of 95% for neurotransmitters and about 90% for ascorbic and uric acids. 相似文献
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