A simple relation is presented to describe the dependence of the volume of a d group metal atom on its magnetic moment using a single constant independent of the atom involved, the crystal structure, atomic enviroment, type and strength of magnetic order. This relation is extended to binary alloys and its significance in special cases discussed. The validity of this relation is checked for a wide range of Fe, Mn and Cr binary alloy systems in subsequent papers. 相似文献
Let be a locally compact abelian group. The notion of Zak transform on extends to . Suppose that is compactly generated and its connected component of the identity is non-compact. Generalizing a classical result for , we then prove that if is such that its Zak transform is continuous on , then has a zero.
Fluorine, the heterosubstituent par excellence , which can have a stronger impact on the reactivity in its vicinity than any other element, may serve as a crucial test of any model of the origin and transmission of electronic effects. To what extent fluoro substituents in organic compounds (A−H) increase their kinetic proton mobility (H/D and H/metal (M) exchange) and thermodynamic acidity in aqueous media and in the gas phase (see below) depends on many factors such as induction, resonance, polarization, hyperconjugation, and dipolar interactions. 相似文献
The similarity between two tandem mass spectra, which were measured on different instruments, was compared quantitatively using the similarity index (SI), defined as the dot product of the square root of peak intensities in the respective spectra. This function was found to be useful for comparing energy-dependent tandem mass spectra obtained on various instruments. Spectral comparisons show the similarity index in a 2D “heat map”, indicating which collision energy combinations result in similar spectra, and how good this agreement is. The results and methodology can be used in the pharma industry to design experiments and equipment well suited for good reproducibility. We suggest that to get good long-term reproducibility, it is best to adjust the collision energy to yield a spectrum very similar to a reference spectrum. It is likely to yield better results than using the same tuning file, which, for example, does not take into account that contamination of the ion source due to extended use may influence instrument tuning. The methodology may be used to characterize energy dependence on various instrument types, to optimize instrumentation, and to study the influence or correlation between various experimental parameters.
