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991.
The outer automorphism group of a nest algebra is canonically isomorphic to the (spatial) automorphism group of the nest itself. The outer automorphism group of the associated quasitriangular algebra is canonically isomorphic to a group of “approximate” automorphisms of the nest. A simple proof that every derivation of a quasitriangular algebra is inner is obtained as a corollary. 相似文献
992.
993.
994.
A. Fraefel J. Seibl Noel W. Davies John C. Bignall Ross W. Lincolne Jaime Espinosa Gonzalez Hans-Friedrich Grützmacher C. Lifshitz M. Goldenberg Y. Malinovich M. Peres Gerhard Holzmann Gernot Frenking Bernd Steiner Gary Caldwell John E. Bartmess Klaus Eckart Helmut Schwarz Shinjiro Kobayashi Hiroshi Taniguchi Helmut Schwarz Klaus Eckart Lester C. E. Taylor 《Journal of mass spectrometry : JMS》1982,17(9):448-460
995.
996.
William T. Foreman Robert E. Sievers Bernd W. Wenclawiak 《Fresenius' Journal of Analytical Chemistry》1988,330(3):231-234
Summary The new selective and sensitive redox chemiluminescence detector (RCD), originally developed for gas chromatography, has been successfully interfaced with a capillary column supercritical fluid chromatograph. Interfacing the SFC-RCD was accomplished simply through utilization of the redox reaction chamber presently used for both capillary and packed column GC. The feasibility of this new separation-detection scheme was demonstrated with SFC chromatograms of antioxidant isomers and some compounds of biological relevance. Mobile phase compatibility and signal quenching are also discussed.
Chromatographie mit überkritischen fluiden phasen unter Verwendung der Redox-Chemiluminescenz-Detektion相似文献
997.
A conjecture concerning vacuum correlations in axiomatic quantum field theory is proved. It is shown that this result can be applied both in the context of EPR-type experiments and Bell-type experiments. 相似文献
998.
Measurements on complex materials are often hampered by the difficulties arising from the prerequisites to control sample uniformity. A new single- and multi-reflection ATR-accessory has been designed for the rapid analysis of many samples under extremely similar experimental conditions. This is performed by passing the ATR-unit, a horizontally mounted ZnSe-prism, by the IR-beam. It includes a gas-tight sample region. Thus, toxic material and even pathogenic bacteria may be measured under controlled conditions. 相似文献
999.
The work function of regularly stepped tungsten single crystal planes has been investigated as function of terrace width and step orientation. The terraces were always formed by (110) planes. One set of samples exhibited step edges running parallel to the [001] direction but different terrace widths. Another set with almost equal terrace width showed step edges of different directions with correspondingly different edge structures. The work function measurements were performed using thermionic emission in the temperature range 2000–2800 K. The work function decreases linearly with step density for a given step orientation. Different step orientations give rise to slightly different work function reductions. The results are interpreted by attributing additional dipole moments to edge atoms. Different edge structures lead to different dipole moments. These findings are consistent with Smoluchowski's “smoothing effect” of the electron charge distribution caused by the structural arrangement of surface atoms. The temperature coefficient of the work function also depends strongly on step density and step orientation. 相似文献
1000.
Hellmut Haberland Bernd von Issendorff Ji Yufeng Thomas Kolar Gregor Thanner 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,26(1):8-12
The change of the cohesive energy and the optical absorption spectra of small singly sized Hg clusters is discussed. The cohesive energy allows one to determine the different regimes of chemical bonding. The optical spectra show an abrupt transition to a collective, plasmon-like absorption as a function of increasing cluster size. The position of the one plasmon peak is: 1) independent of the charge state, 2) nearly independent of cluster size, and 3) agrees with that of the classical Mie plasmon calculated from the experimental dielectric constants. The width of the plasmon peaks is discussed. A strong influence of electronic correlations on the cluster size dependence of the oscillator strength is observed. 相似文献