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51.
J. Bustad C. Enkvist S. Lunell S. Svensson 《Journal of Electron Spectroscopy and Related Phenomena》1995,70(3):233-244
The satellite structure of the C1s and O1s photoelectron spectra of chromium hexacarbonyl Cr(CO)6 has been calculated by the INDO/CI method and compared with available high resolution core level photoelectron spectra. A reassignment of some of the lines is made. It is found that the satellite structure in both cases is dominated by excitations from metal-ligand bonding to metal-ligand antibonding Me(3d)-π* orbitals, and that these shake-up excitations involve a significant charge transfer to the core ionized ligand from the rest of the molecule. 相似文献
52.
In this paper we give a unified framework for the construction of complex valued harmonic morphisms from the real, complex and quaternionic Grassmannians and their non-compact duals. This gives a positive answer to the corresponding open existence problem in the real and quaternionic cases.
Mathematics Subject Classifications (2000): 58E20, 53C43, 53C12The author is a member of EDGE, Research Training Network HPRN-CT-2000-00101 相似文献
53.
In new neutron scattering measurements on4He at saturated vapour pressure (SVP), we have probed to within 0.0007 K of Tλ from below, revealing a dramatic increase in the damping rate of the momentum fluctuations and a marked softening of the
roton frequency, with the changes occurring primarily very close to Tλ and being complete at Tλ. In contrast to 20 bars, the roton at SVP does not, however, go completely soft. Above Tλ, the modes are strongly damped and overlapping whereas at 20 bars they are overdamped (non-propagating). 相似文献
54.
SCF and limited CI calculations have been performed for a number of excited states of doubly ionized water. The calculations allowed an assignment of both the Auger spectrum and most of the satellites in the soft X-ray spectrum. The assignment for the two highest peaks in the Auger spectrum was ambiguous. SCF calculations of the K emission spectrum of H2O were also performed. It was found that limited CI calculations were of importance for some states with two open shells in one symmetry. Such effects are caused by large off-diagonal lagrangian multiplies connecting the open shells in the reference configuration. 相似文献
55.
56.
A Gunnarsson J Lundsten S Svensson 《Acta chemica Scandinavica. Series B: Organic chemistry and biochemistry》1984,38(7):603-609
A number of glycosphingolipids have been subjected to trifluoroacetolysis. Heating the glycosphingolipid at 100 degrees C for 48 h in mixtures of trifluoroacetic acid (TFA) and trifluoroacetic anhydride (TFAA) varying from 1:1 to 1:100 (v/v) resulted in complete cleavage of the glycosidic bond between the carbohydrate and the unsaturated base of the ceramide. The fatty acid(s) linked to the amino group of sphingosine were also released by transamidation. The carbohydrate portion was stable under these conditions due to stabilization of the glycosidic bonds by the electronegative O-trifluoroacetyl groups. The 2-acetamido-2-deoxy-hexose units in the glycosphingolipids were converted into their N-trifluoroacetyl analogues. The N-trifluoroacetyl functions could be removed and the 2-acetamido-2-deoxy-hexoses could be reconstituted by N-acetylation. 相似文献
57.
Sven Svensson 《Polymer Testing》1981,2(3):161-174
The main purpose of this investigation was to find out if laboratory fatigue tests in tension give results which can be useful in predicting the service life of a vibration isolator.Four natural rubber vulcanizates with different curing systems were used in the tests. The fatigue life in cyclic loading was determined in tension on standard tensile specimens (dumb-bells) and in shear on two types of vibration isolators. The results indicate that the information achieved in tension is relevant for estimating the service life of an isolator. Both relaxing and non-relaxing tests in tension were made and the relaxing tests seem to give the best correlation between dumb-bells and isolators. As the relaxing tests are also the least time-consuming they are to be preferred for material testing. 相似文献
58.
59.
Neutron inelastic scattering from 4He at T = 2.3 K shows that for Q ? 2 nm?1 “sound-wave” excitations propagate with the characteristics of ordinary or first sound while for Q ? 3 nm?1 they propagate with the characteristics of zero sound. 相似文献
60.
Hyland B Svensson CE Ball GC Leslie JR Achtzehn T Albers D Andreoiu C Bricault P Churchman R Cross D Dombsky M Finlay P Garrett PE Geppert C Grinyer GF Hackman G Hanemaayer V Lassen J Lavoie JP Melconian D Morton AC Pearson CJ Pearson MR Phillips AA Schumaker MA Smith MB Towner IS Valiente-Dobón JJ Wendt K Zganjar EF 《Physical review letters》2006,97(10):102501
A high-precision branching ratio measurement for the superallowed beta+ decay of 62Ga was performed at the Isotope Separator and Accelerator radioactive ion beam facility. Nineteen gamma rays emitted following beta+ decay of 62Ga were identified, establishing the dominant superallowed branching ratio to be (99.861+/-0.011)%. Combined with recent half-life and Q-value measurements, this branching ratio yields a superallowed ft value of 3075.6+/-1.4 s for 62Ga decay. These results demonstrate the feasibility of high-precision superallowed branching ratio measurements in the A>or=62 mass region and provide the first stringent tests of the large isospin-symmetry-breaking effects predicted for these decays. 相似文献