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相似文献
8.
E. P. Naiden V. A. Zhuravlev V. I. Itin O. G. Terekhova A. N. Tyukpiekov 《Journal of Structural Chemistry》2004,45(1):S106-S110
Hexagonal ultradispersed ferrites were obtained in a high energy planetary mill by mechanochemical treatment. Their structural characteristics — average size and internal stress — were studied. Fundamental magnetic characteristics — saturation magnetization and effective fields of crystal anisotropy — were examined in pulse magnetic fields with the law of approach to saturation, as well as by ferromagnetic resonance technique in the 26–53 GHz frequency range. It was demonstrated that size reduction of powders to a few tens of nanometers influenced significantly the effective anisotropy field. A model accounting for anisotropy contribution from the disturbed subsurface layer and magnetoelastic interactions was suggested. Mechanical activation was shown to be an alternative to chemical substitution for magnetic anisotropy control. 相似文献
9.
Grigor’ev Arthur A. Kayukov Yakov S. Nikiforova Anastasiya L. Karpov Sergey V. Shchegravina Ekaterina S. Kayukova Olga V. Tafeenko Victor A. 《Chemistry of Heterocyclic Compounds》2019,55(2):167-171
Chemistry of Heterocyclic Compounds - 4-Acyl-2-amino-6-chloropyridine-3,5-dicarbonitriles underwent heterocyclization in the presence of ammonia in aqueous dioxane medium, involving the... 相似文献
10.
The paper is concerned with the two-machine flow shop, where each job requires an additional resource (referred to as storage space) from the start of its first operation till the end of its second operation. The storage requirement of a job is determined by the processing time of its first operation. At any point in time, the total consumption of this additional resource cannot exceed a given limit (referred to as the storage capacity). The goal is to minimise the makespan, i.e. to minimise the time needed for the completion of all jobs. This problem is NP-hard in the strong sense. The paper analyses how the parameter - a lower bound on the storage capacity specified in terms of the processing times, affects the computational complexity. 相似文献 |