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11.
Steven Schmidt Gü nter Lattermann Ralf Kleppinger Joachim H. Wendorff 《Liquid crystals》1994,16(4):693-702
Liquid crystalline complexes with chromium, molybdenum and with tungsten as metallic centres are reported. 1,4,7-Trisubstituted 1,4,7-triazacyclononane and three carbonyl groups are coordinated in an octahedral geometry. The observed mesophases are characterized as disordered rectangular columnar of a pyramidic type. 相似文献
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The purpose of this paper is to review the mechanisms and available theoretical methods for modeling the strength and failure of thin film/substrate systems 相似文献
14.
Mathias Getzlaff Joachim Bansmann Gerd Schönhense 《Fresenius' Journal of Analytical Chemistry》1995,353(5-8):743-747
Investigations of the electronic and magnetic properties of oxygen adsorbed on magnetized iron films have been carried out by means of angle and spin resolving photoelectron spectroscopy. Iron, epitaxially grown on W(100) and W(110) crystals, served as the ferromagnetic substrate. Exchange splittings of the O 2px derived level have been detected, demonstrating a magnetic coupling between the chemisorbate and the iron layer. Variations of the exchange splitting have occurred as a function of the oxygen coverage, photon energy, and emission angle. High oxygen exposures have lead to a FeO overlayer at the surface. 相似文献
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D. Gross 《Applied physics. B, Lasers and optics》2007,86(3):367-370
According to a classical result due to Hudson, the Wigner function of a pure, continuous-variable quantum state is non-negative
if and only if the state is Gaussian. We have proven an analogous statement for finite-dimensional quantum systems. In this
context, the role of Gaussian states is taken on by stabilizer states. The general results have been published in [1]. For
the case of systems of odd prime dimension, a different, greatly simplified method of proof can be employed which still exhibits
the main ideas. The present paper gives a self-contained account of these methods.
PACS 03.65.Fd; 03.65.Sq; 03.67.-a 相似文献
18.
Juan Pablo Trelles Emil Pfender Joachim Heberlein 《Plasma Chemistry and Plasma Processing》2006,26(6):557-575
The dynamics of the electric arc inside a direct current non-transferred arc plasma torch are simulated using a three-dimensional, transient, equilibrium model. The fluid and electromagnetic equations are solved numerically in a fully coupled approach by a multiscale finite element method. Simulations of a torch operating with argon and argon–hydrogen under different operating conditions are presented. The model is able to predict the operation of the torch in steady and takeover modes without any further assumption on the reattachment process except for the use of an artificially high electrical conductivity near the electrodes, needed because of the equilibrium assumption. The results obtained indicate that the reattachment process in these operating modes may be driven by the movement of the arc rather than by a breakdown-like process. It is also found that, for a torch operating in these modes and using straight gas injection, the arc will tend to re-attach to the opposite side of its original attachment. This phenomenon seems to be produced by a net angular momentum on the arc due to the imbalance between magnetic and fluid drag forces. 相似文献
19.
Thomas Drewello Rainer Herzschuh Joachim Stach 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1993,28(4):339-343
A triple stage hybrid mass spectrometer was scanned for the trapping of the reaction intermediates of the over-all loss of two CsI-moieties from size-selected caesium iodide cluster ions of the general formula Cs (CsI)+ n . In addition to appropriate MS/MS/MS-methods an electrically floated collision cell has been applied to trap intermediates of unimolecular and collision-induced evaporations. In comparison with other experimental findings the features of the evaporation mechanism are discussed. 相似文献
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