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71.
Ulrich Von Gemmingen 《Surface science》1982,120(2):334-345
Yields of ion impact induced electrons from very pure Ni(110) and Ni(111) surfaces have been measured. In several tilt planes the angle of incidence of a 5 keV H+, H+2 or H+3 ion beam is varied from perpendicular to grazing incidence. Below = 75° the yield increases as sec but shows characteristic depressions when the beam is incident along crystallographically low indexed lattice directions. This is explained by kinetic electron emission with respect to the projectile transparency of the crystal lattice. 相似文献
72.
S. Von Laven D.T. Speer M. Stockton 《Journal of Quantitative Spectroscopy & Radiative Transfer》1981,25(3):249-252
The 447.1 nm line of neutral helium has been used to measure the time-dependent decay of the electron density in the afterglow of a pulsed, atmospheric pressure helium discharge. The technique involves using a shutter which consists of a Pockels cell combined with crossed polarizers to gate the light pulse, allowing observation of the spectrum during various time windows in the discharge. 相似文献
73.
74.
Von Schneider Michael 《Abhandlungen aus dem Mathematischen Seminar der Universit?t Hamburg》1978,47(1):150-170
Abhandlungen aus dem Mathematischen Seminar der Universität Hamburg - 相似文献
75.
Yuan-Fang Liu Cheng Luo K. J. Moody D. Lee G. T. Seaborg H. R. Von Gunten 《Journal of Radioanalytical and Nuclear Chemistry》1983,76(1):119-124
Two procedures are described for fast separations of berkelium from complex mixtures of reaction products arising from heavy
ion reactions, such as18O+248Cm. The first procedure uses a combination of several extraction steps with a final separation on a cation exchanger, the
second procedure starts with an anion exchange column which is followed by multiple extractions in different media. The elements
separated in the different steps were analyzed and overall decontamination factors are given. 相似文献
76.
The dielectric absorption of vitreous silica containing 1200 ppm of OH?-impurities has been measured at 10 GHz in the temperature range between 0.4 K and 8 K. A strong intensity dependence of the absorption coefficient has been observed at temperatures below 3 K. 相似文献
77.
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79.
We use the numerical renormalization group method to calculate the single-particle matrix elements T of the many-body T matrix of the conduction electrons scattered by a magnetic impurity at T=0 temperature. Since T determines both the total and the elastic, spin-diagonal scattering cross sections, we are able to compute the full energy, spin, and magnetic field dependence of the inelastic scattering cross section sigma(inel)(omega). We find an almost linear frequency dependence of sigma(inel)(omega) below the Kondo temperature T(K), which crosses over to a omega(2) behavior only at extremely low energies. Our method can be generalized to other quantum impurity models. 相似文献
80.
Oomens J Moore DT Von Helden G Meijer G Dunbar RC 《Journal of the American Chemical Society》2004,126(3):724-725
Infrared spectroscopy of gas-phase Cr+ complexes of aniline was studied using the FELIX free electron laser interfaced to a Fourier transform ion cyclotron resonance spectrometer. For both the monomer complex Cr+(aniline) and the dimer complex Cr+(aniline)2 the spectra showed features indicating binding of the metal ion to the aromatic pi cloud, as opposed to the nitrogen atom. Agreement with DFT-calculated infrared absorption spectra for the ring-bound complexes was good using the MPW1PW91 functional, but the B3LYP functional predicted the wrong binding site. The spectroscopic results resolve the ambiguity in computational prediction of the preferred binding site and support the use of the MPW1PW91 functional for these systems. 相似文献