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61.
Shane A. Dunn 《Experimental Mechanics》1993,33(1):32-36
Stress measurement by means of the thermoelastic technique has been growing in popularity since the mid-1980s. This paper
looks in detail at the effects of thermal conduction on such measurements. It is shown that for accurate quantitative stress
determination, on all but the simplest of geometries, thermal-conduction effects may have to be considered. Such effects can
be experimentally observed and modifications which can be made to an experiment affected by thermal conduction are suggested. 相似文献
62.
A series of sulphonyl azides decomposed upon electron-impact with loss of azide radical. This fragmentation was in marked contrast to the photochemical behaviour of the compounds. An interesting ortho-extrusion process occurred in the mass spectrum of 2,4,6-triisopropylbenzenesulphonyl azide. 相似文献
63.
M. Dunn 《Zeitschrift für Physik A Hadrons and Nuclei》1988,330(2):197-201
We show that the dinotor is sensitive to discrete energy level corrections to the continuum approximation for the density of states. These corrections do not destroy the metastability of the dinotor, but may produce a ‘magic number’ effect. New metastable configurations of the dinotor may also exist, possibly creating further difficulty identifying the dinotor as the cause of the anomalon effect. 相似文献
64.
Ohne Zusammenfassung 相似文献
65.
T. Bartsch A. Müller W. Spies J. Linkemann H. Danared D.R. DeWitt H. Gao W. Zong R. Schuch A. Wolf G.H. Dunn 《Hyperfine Interactions》1997,108(1-3):177-183
Cross sections for dielectronic recombination can be influenced by the presence of external electric fields in the electron--ion
collision region. In most of the previous experiments with multiply charged ions such fields were present but unknown. Therefore,
comparisons of experimental results with theoretical calculations were ambiguous: for obtaining best possible agreement, theory
could use the field strength as a free parameter to adjust the calculated cross sections to the experiment. In recent measurements
with 10 MeV/u Si11+ ions stored in CRYRING, controlled external motional electric fields up to 183 V/cm were introduced in the electron cooler.
Significant cross section enhancements were found for Rydberg states n > 20.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
66.
The low temperature fluorescence spectra (4.2 K) of solid solutions of p-difluorobenzene-h4 (pDFB-h4) and -d4 have been recorded and analyzed. The absence of fluorescence from vibrationally excited states at 4.2 K eliminates the sequence and “hot band” structure which complicate the analysis of the vapor fluorescence spectrum. On the basis of a comparison of our vibrational analysis with those published for the vapor phase fluorescence, several incorrect assignments in the latter have been identified. The high resolution and lack of spectral congestion obtained in the low temperature matrix isolated fluorescence spectra also allowed additional vibrational assignments to be made. These results are of added importance because of the extensive use which has been made of pDFB for radiationless relaxation studies in the vapor phase. The phosphorescence spectrum of crystalline pDFB-h4 was observed with sufficient intensity to locate the electronic origin to make several vibrational assignments. Additionally, the zero-field splitting of the first triplet excited state was measured by optically detected magnetic resonance techniques. 相似文献
67.
68.
69.
Tuneable stimulated Stokes emission is generated at ≈2.9 μm in barium vapor with an oscillator-amplifier dye laser. The conversion efficiency is as high as 40% and the energy output as high as 30 mJ. The emission is tuneable over ≈100 cm-1. At high vapor pressures the tuning profile is markedly asymmetric. 相似文献
70.