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21.
In this study, slow strain rate tensile testing at elevated temperature is used to evaluate the influence of temperature and strain rate on deformation behaviour in two different austenitic alloys. One austenitic stainless steel (AISI 316L) and one nickel-base alloy (Alloy 617) have been investigated. Scanning electron microscopy related techniques as electron channelling contrast imaging and electron backscattering diffraction have been used to study the damage and fracture micromechanisms. For both alloys the dominante damage micromechanisms are slip bands and planar slip interacting with grain bounderies or precipitates causing strain concentrations. The dominante fracture micromechanism when using a slow strain rate at elevated temperature, is microcracks at grain bounderies due to grain boundery embrittlement caused by precipitates. The decrease in strain rate seems to have a small influence on dynamic strain ageing at 650°C. 相似文献
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V. V. Alekseenko D. M. Gromushkin Yu. V. Sten’kin 《Bulletin of the Russian Academy of Sciences: Physics》2011,75(6):857-859
Thermal neutron fluxes were measured using two types of scintillation detectors based on the inorganic scintillator ZnS(Ag):
6LiF+ZnS(Ag) and 10B2O3 + KCl+ZnS(Ag). The preliminary results from these measurements are given. The thermal neutron concentration as a function
of altitude above sea level was determined. The measurements were performed at three locations: in Moscow, at the Baksan Neutrino
Observatory of the Russian Academy of Sciences, and at the Gran Sasso National Laboratory. Variations of neutron count rates
associated with lunar cycles were observed at the remote laboratories. 相似文献
25.
V. V. Bolotov N. A. Davletkil’deev A. A. Korotenko V. E. Roslikov Yu. A. Sten’kin 《Technical Physics》2011,56(11):1593-1598
The layer-by-layer distribution of components in a porous silicon-tin oxide nanocomposite produced by the following three
methods is studied by spectroscopic ellipsometry: chemical vapor deposition, atomic layer deposition, and magnetron sputtering.
It is shown that, in the nanocomposites fabricated by these methods, SnO
x
penetrates to a depth more than 400 nm and is nonuniformly distributed over the porous layer thickness. The nanocomposite
prepared by magnetron sputtering followed by heat treatment has the maximum penetration depth and the maximum uniformity of
layer-by-layer SnO
x
distribution. 相似文献
26.
Ab initio MO -LCAO -SCF calculations using an STO -3G basis set were performed to find the most stable conformations of L -serine phosphate and hydrated L -serine phosphate. The most favorable conformation of L -serine phosphate is found to be one where the bond sequence O? C? C? C is trans and P? O? C? C gauche, and a very short hydrogen bond is formed between an oxygen atom of the phosphate group and a hydrogen atom of the ammonium group. For hydrated L -serine phosphate, a bridge-type hydration in which a water molecule links a phosphate oxygen and an ammonium hydrogen displays particularly low energy. In the four-hydrated L -serine phosphate anion, the most favorable conformation is such a bridged one having a rather extended configuration with regard to the bond sequences O? C? C? C and P? O? C? C. 相似文献
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Sten Kaijser 《Arkiv f?r Matematik》1978,16(1-2):179-193
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