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51.
We report the results of heat capacity, SQUID magnetometry, and x-ray diffraction studies of polycrystalline and magnetically aligned Ca 2+xY 2-xCu 5O (10), a quasi-1D compound. As holes are doped into the chains from x = 0-2, the data indicate a change from 3D long-range order to 1D chain behavior to cluster behavior. We quantitatively model the magnetic and thermal properties of heavily doped Ca 4Cu 5O (10) in terms of spin clusters. Anisotropic susceptibility data indicate a doping-independent easy axis of magnetization perpendicular to the planes containing the chains; also, a spin-flop transition is observed, providing a measure of the anisotropy field. 相似文献
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Structure-Activity Relationships of Odorants with a Bicyclo[2.2.2]octane System The synthesis of the olfactory interesting homonojigikualcohol 2 and of its epimer 10 leads to the keto alcohols 6a, b and 7a, b as intermediates. The latter have OH and C?O groups (an AH/B system) fixed at the rigid bicyclic nucleus at different distances (2.8 and 4.7 Å) and confirm Ohloff's rule for odoriferous properties which is based on this distance. 相似文献
54.
The radiative lifetimes of the b1Σ+ and a1Δ states have been evaluated by perturbation expansions including X3Σ−, a1Δ, b1Σ+, 13,1Π, 23,1Π, 23Σ− and 21Σ+ states. All wavefunctions result from large MRD CI calculations. The b—X transition is dominated by the parallel transition moment; it is found to be much stronger than the a—X transition. The calculated radiative lifetimes of τ(1Σ+)=18 ms, τ(1Δ)=2.2 s for NF and τ(1Σ+)=2.5–3.5 ms for NCl are in good accord with corresponding experimentally deduced values. The lifetime for the a1Δ state in NCl is found to be τ(1Δ)=1.1 s, ie. much longer than derived from a recent experiment. Its magnitude is consistent with the τ(b1Σ+)/τ(a1Δ) ratio of similar systems and with the decrease in lifetime from NF to NCl and is thus believed to be quite reliable. A detailed analysis of all contributions of the perturber states to the transition mechanism is made and comparison with the related data in SO, O2 and S2 is undertaken. The b-a transition probability dominated by the quadrupole transition is fairly constant in all the systems in the order of A = 0.013 (NF) - 0.0013 (S2) s−1. 相似文献
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M. Shepherd E. R. Weaver P. G. Ledig Aktiebolaget Carba K. Melanby H. L. Harden P. Borinski H. Murschhauser R. Staufer R. Krais H. Markert H. Mogilnickij H. Heinicke K. Heimberger L. C. Mc Nair H. C. Gull St. Hediger E. Lieber R. Rosen K. M. Watson und N. H. Ceaglske 《Fresenius' Journal of Analytical Chemistry》1933,92(1-2):31-40
Ohne Zusammenfassung 相似文献
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Markus Bacher Karl Baumann Hermann Knapp Andrea Steck Sigrid Teibl 《Magnetic resonance in chemistry : MRC》2009,47(1):71-83
The complete 1H and 13C NMR data of 27 pravastatin derivatives are presented. Assignment was achieved by use of 1D and 2D NMR experiments (selective 1D NOE, COSY, NOESY, HSQC, HMBC). Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
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