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121.
Michael L. Gross 《Journal of mass spectrometry : JMS》1972,6(8):827-831
Ion Cyclotron Resonance Spectrometry Is Proposed As The Method For Evaluating ‘Kinetic Shifts.’ The Proposal Is Tested By A Comparison Of The Appearance Potentials For Some Simple Cleavage Reactions With Those For Some Cleavage And Rearrangement Fragmentations In Benzene, Benzonitrile, Anisole, Aniline And Cubane. 相似文献
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A model is given for the self-ionization of halogen fluorides, in particular for bromine trifluoride, and the arguments for and against the self-ionization are critically discussed. From our work and based on 18F tracer exchange studies and electrochemical, spectroscopic and chemical investigations, it appears as if the ionization of BrF5 is very small and relatively unimportant. The halogen fluorides react with Lewis acids and bases as molecular compounds involving donor-acceptor mechanisms. 相似文献
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Andrianasolo EH Gross H Goeger D Musafija-Girt M McPhail K Leal RM Mooberry SL Gerwick WH 《Organic letters》2005,7(7):1375-1378
[structure: see text] Chemical investigation of two field collections of marine cyanobacteria has led to the discovery of two new cytotoxic natural products, ankaraholides A (2) and B (3), along with the known compound swinholide A (1). Since swinholide-type compounds were previously localized to the heterotrophic bacteria of sponges, these findings raise intriguing questions about their true metabolic source. 相似文献
128.
Floris A Profeta G Lathiotakis NN Lüders M Marques MA Franchini C Gross EK Continenza A Massidda S 《Physical review letters》2005,94(3):037004
Solid MgB(2) has rather interesting and technologically important properties, such as a very high superconducting transition temperature. Focusing on this compound, we report the first nontrivial application of a novel density-functional-type theory for superconductors, recently proposed by the authors. Without invoking any adjustable parameters, we obtain the transition temperature, the gaps, and the specific heat of MgB(2) in very good agreement with experiment. Moreover, our calculations show how the Coulomb interaction acts differently on sigma and pi states, thereby stabilizing the observed superconducting phase. 相似文献
129.
Goennenwein ST Wassner TA Huebl H Brandt MS Philipp JB Opel M Gross R Koeder A Schoch W Waag A 《Physical review letters》2004,92(22):227202
We show that upon exposure to a remote dc hydrogen plasma, the magnetic and electronic properties of the dilute magnetic semiconductor Ga1-xMnxAs change qualitatively. While the as-grown Ga1-xMnxAs thin films are ferromagnetic at temperatures T less, similar 70 K, the samples are found to be paramagnetic after the hydrogenation, with a Brillouin-type magnetization curve even at T=2 K. Comparing magnetization and electronic transport measurements, we conclude that the density of free holes p is significantly reduced by the plasma process, while the density of Mn magnetic moments does not change. 相似文献
130.
The synthesis of a cofacial bis-porphyrinic tweezer bearing a tris-anthracenic spacer is reported. Its behavior as host has been evidenced as well as the ability of its cavity to adjust to guests of various sizes. 相似文献