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181.
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D. Riegel 《Hyperfine Interactions》1989,49(1-4):439-449
By application of the perturbed γ-ray distribution method combined with heavy-ion reactions and recoil implantation techniques,
we have found an experimental was of producing and investigating localized 3d and 4d states in metals. 3d and 4d ions in sp
metal hosts, in particular in alkali metals, exhibit the phenomena of large orbital magnetism, extremely small spin fluctuation
rates, well defined ionic ground states, mixed valence, and crystal field splittings smaller than theLS coupling. These results upset long standing assumptions about the nature of d states in metals and their magnetic instabilities
due to interaction of d orbitals with conduction electrons. If magnetic, the d states of 3d and 4d ions cannot be described
by one electron approaches based on Anderson type models but required an analysis based on ionic configurations. The tendencies
towards reduced magnetism can be well reproduced by increasing spin fluctuations which gives new insight into antiferromagnetic
d-sp exchanges and the Kondo problem for d ions in sp metals. Localized ionic d states, large orbital effects, small crystal
fields, and mixed valence-these new phenomena for d ions in sp metals exhibit common basic features with stable and unstable
4f and 5f systems but reflect qualitative differences to the spin dominated magnetism of 3d ions in Cu, Ag, Au and in d metal
hosts. 相似文献
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Clemens Schwarzinger Angelika Pfeifer Harald Schmidt 《Monatshefte für Chemie / Chemical Monthly》2002,49(5):1-7
Analytical pyrolysis in combination with gas chromatography and mass spectrometry or a nitrogen-phosphorus detector, respectively, were used to characterize the quaternization reagent glycidyltrimethylammonium chloride and a cationic cotton fabric. Trimethylamine was shown to be the most abundant nitrogen-containing product in the pyrolysis of glycidyltrimethylammonium chloride and was thus used for the quantification of the nitrogen content of the cationic cotton fabric. The results were compared to those obtained by traditional methods such as Kjeldahl and elemental analysis. It could be shown that pyrolysis is well suited for monitoring the nitrogen content of cellulose fibers. 相似文献
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