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Employing positive-definiteness arguments we analyse Boson field states, which combine classical and quantum mechanical features (signal and noise), in a constructive manner. Mathematically, they constitute Bauer simplexes within the convex, weak-*-compact state space of the C*-Weyl algebra, defined by a presymplectic test function space (smooth one-Boson wave functions) and are affinely homeomorphic to a state space of a classical field. The regular elements are expressed in terms of weak distributions (probability premeasures) on the dual test function space. The Bauer simplex arising from the bare vacuum is shown to generalize the quantum optical photon field states with positive P-functions. 相似文献
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We describe an improved high-performance liquid chromatographic method for the determination of tyrosine, 5-hydroxytryptamine, 5-hydroxyindoleacetic acid, tryptophan and homovanillic acid in cerebrospinal fluid and nerve tissue, using the new microbore cartridges with 5 micron average particle size. The first four substances are quantified fluorometrically and the last two electrochemically. Both detectors are connected to the same integrator through a relay which can be switched as required. Data are collected in an on-line personal computer and evaluated statistically. An improvement in the method for extraction and separation of catecholamines is also reported. 相似文献
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For the major, minor and trace element analysis of the inorganic compounds of a Ruhr-Saar coal different preparation techniques are investigated with X-ray fluorescence analysis, electron microprobe and classical wet chemical methods minimizing sample weight at standard preparation times and analytical accuracies. Considering accuracy as well as preparation efforts, determinations by electron microprobe on small sample amounts (<50 mg) proved to be superior to the other methods.Abbreviations AAS
atomic absorbtion spectrometry
- EMA
electron microprobe analysis
- IC
ion chromatography
- ISE
ion sensitive electrode
- PHOT
photometry
- WCA
wet chemical analysis
- XRF
X-ray fluorescence analysis
- LTA
low temperature plasma ashing
- HTA
high temperature ashing
- l.o.i.
loss on ignition 相似文献
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Edgar Heilbronner Evi Honegger Jacques Lecoultre Cyril A. Grob Raymond Houriet Eric Rolli 《Helvetica chimica acta》1986,69(8):2114-2126
The n ionization energies I and the gas-phase basicities GB of CH3-, Cl-, or CN-substituted quinuclidines have been measured by PE and ICR spectroscopy. The dependence of the shifts ΔI and ΔGB (relative to the values of the parent molecule) allow conclusions about the charge dispersal accompanying the n ionization or the protonation of quinuclidine in the gas phase. The agreement with the results of a minimal basis set ab initio calculation is excellent. Comparison of the solution pKa values with either I or GB reveals that 2-substituted quinuclidines exhibit sizeable solvent-induced proximity effects, i.e. that the corresponding quinuclidinium ions are more acidic in solution than expected on the basis of the gas-phase basicities. This agrees with earlier results concerning 2-substituted pyridines. 相似文献
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Stefan Pitsch Patrick A. Weiss Xiaolin Wu Damian Ackermann Thomas Honegger 《Helvetica chimica acta》1999,82(10):1753-1761
Two sets of RNA phosphoramidites, carrying the (fluoride-labile) 2′-O-[(triisopropylsilyl)oxy]methyl (=tom) group and the (photolabile) [(R)-1-(2-nitrophenyl)ethoxy]methyl (=(R)-npeom) group, were prepared (see 1 – 4 and 5 – 8 , resp.). The two protecting groups were completely orthogonal to each other. Three ribozyme-substrate constructs, protected each by a (R)-npeom group, were synthesized; on photolysis, efficient cleavage of this remaining protecting group occurred (Scheme 3). It could be demonstrated that the presence of one (R)-npeom group within a RNA strand has only a minor influence on the pairing properties of corresponding duplexes. 相似文献
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Reinhard Honegger 《Letters in Mathematical Physics》1993,27(3):191-203
By means of cocycle techniques in a recent paper, the global dynamics of mean field-boson couplings has been studied. Here, by restricting to the bosonic system the infinite time limit (t ) for very general initial states, one obtains time-asymptotic states on the bosonicC
*-Weyl algebra, in which one partially rediscovers the collective ordering of the infinite mean field lattice. 相似文献
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It is shown that for classical, analytical states of the Weyl algebra, the quantum optical coherence condition of second order implies those of nth order for all n2. 相似文献
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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