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151.
M. V. Semenova 《Siberian Mathematical Journal》2007,48(1):156-164
We prove that the class of the lattices embeddable into subsemigroup lattices of n-nilpotent semigroups is a finitely based variety for all n < ω. Repnitski? showed that each lattice embeds into the subsemigroup lattice of a commutative nilsemigroup of index 2. In this proof he used a result of Bredikhin and Schein which states that each lattice embeds into the suborder lattices of an appropriate order. We give a direct proof of the Repnitski? result not appealing to the Bredikhin-Schein theorem, so answering a question in a book by Shevrin and Ovsyannikov. 相似文献
152.
Investigation of the 19F(n, α)16N reaction excitation function in neutron energy range of 4–7.35 MeV
I. P. Bondarenko V. A. Khryachkov T. A. Ivanova B. D. Kuzminov N. N. Semenova A. I. Sergachev 《Bulletin of the Russian Academy of Sciences: Physics》2013,77(4):459-461
New method based on ionization chamber with Frisch grid and digital signal processing was developed for experimental investigation of 19F(n, α)16N reaction. The chamber filling gas with CF4 additive was used as the fluorine-containing target. The experimental investigation of 19F(n, α)16N reaction cross-section in 4–7.35 MeV energy range is represented in this work. The total cross section of 19F(n, α)16N reaction was measured as well as partial cross-section for sum of α0-α3 and sum of α4 and α5 reaction channels. 相似文献
153.
N. I. Kadyrova Yu. G. Zainulin A. P. Tyutyunnik A. S. Semenova N. V. Melnikova I. S. Ustinova 《Bulletin of the Russian Academy of Sciences: Physics》2013,77(3):239-241
The perovskite-like compound Dy x Cu3V4O12 (x = 0.67–0.75) is synthesized under high pressure (P = 4.0–9.0 GPa) and temperature (T = 1000°C). Its crystal structure is determined (Im-3 space group, Z = 2, a = 7.29348(7) Å) by means of powder X-ray diffraction. The basic lengths and bond angles are defined. It is found that the high-pressure phase of Dy x Cu3V4O12 is characterized by metallic conductivity and paramagnetic properties. 相似文献
154.
We find a syntactic characterization of the class \(\mathrm{\mathbf{SUB}}(\mathcal{S})\cap\mathrm{Fin}\) of finite lattices embeddable into convexity lattices of a certain class of posets which we call star-like posets and which is a proper subclass in the class of N-free posets. The characterization implies that the class \(\mathrm{\mathbf{SUB}}(\mathcal{S})\cap\mathrm{Fin}\) forms a pseudovariety. 相似文献
155.
D.G. Kellerman Yu.G. Chukalkin N.A. Mukhina V.S. Gorshkov A.S. Semenova A.E. Teplykh 《Journal of magnetism and magnetic materials》2012
V-substituted LiMnPO4 has been synthesized by the solid state reaction route. Combined Rietveld refinement of neutron and X-ray data revealed that all vanadium ions are located in the same positions as the phosphorus ions. The magnetic structure of LiMnP0.85V0.15O4 was found to be the same as that described for undoped antiferromagnetic LiMnPO4 (TN=34.5 K). DC-magnetization measurements were carried out to study the peculiarities of magnetic ordering in LiMnP0.85V0.15O4. An irreversible behavior of DC magnetization was found at magnetic fields less than ∼2 kOe. It was demonstrated that an increase in the magnitude of the applied field leads to a reduction of the discrepancy between zero-field-cooled and field-cooled processes. These effects were explained by the movement of domain walls and by transition of the system to a monodomain state. The anomaly in the magnetization vs field dependence attributed presumably to the spin-flop transition was observed at ∼40 kOe. The existence of magnetic inhomogeneity in the paramagnetic phase of LiMnP0.85V0.15O4 was proved by the analysis of the χ?T product. It was concluded that the observed changes in χ?T are indicative of a competition between ferromagnetic and antiferromagnetic correlations at temperatures slightly exceeding TN. 相似文献
156.
Yu. B. Kotov V. D. Popov T. A. Semenova V. F. Fedorov 《Russian Journal of Physical Chemistry B, Focus on Physics》2012,6(1):109-111
The special features of the generation of microwave radiation by a high-power air explosion accompanied by ionizing radiation
are discussed. Coherent pulse caused by asymmetry of the ejection of gamma quanta from a source, incoherent bremsstrahlung
of a partially ionized plasma, incoherent radiation of the shock wave front, and radiation in spectral lines lying inside
air transparency windows are considered. 相似文献
157.
Weihong Lin Ejiofor AD EzekweJr Zhen Zhao Emily R Liman Diego Restrepo 《BMC neuroscience》2008,9(1):114
Background
The main olfactory epithelium (MOE) in the nasal cavity detects a variety of air borne molecules that provide information regarding the presence of food, predators and other relevant social and environmental factors. Within the epithelium are ciliated sensory neurons, supporting cells, basal cells and microvillous cells, each of which is distinct in morphology and function. Arguably, the least understood, are the microvillous cells, a population of cells that are small in number and whose function is not known. We previously found that in a mouse strain in which the TRPM5 promoter drives expression of the green fluorescent protein (GFP), a population of ciliated olfactory sensory neurons (OSNs), as well as a population of cells displaying microvilli-like structures is labeled. Here we examined the morphology and immunocytochemical properties of these microvillous-like cells using immunocytochemical methods. 相似文献158.
The temperature dependence of a macrobending bare-fiber-based edge filter is investigated both theoretically and experimentally. The fiber used is a high-bend loss fiber, type 1060XP. The experimental results show a good agreement with the proposed theoretical model over a temperature range from 0 degrees C to 80 degrees C. It is shown that the strong temperature dependence of a high-bend loss fiber has a significant influence on the performance of a fiber edge filter used in a wavelength measurement application. However, it is also concluded that such a temperature-dependent performance can be beneficially utilized in a fiber temperature sensing application. 相似文献
159.
160.
Gorbenko D. A. Belashov A. V. Belyaeva T. N. Kornilova E. S. Litvinov I. K. Semenova I. V. Vasyutinskii O. S. 《Technical Physics》2021,66(1):145-148
Technical Physics - The dynamics of synthesis and accumulation of protoporphyrin IX induced by 5-aminolevulinic acid (5-ALA) was studied using confocal fluorescence microscopy in three established... 相似文献