Dependence of the yield stresses of certain materials on loading rate

The dependence of the dynamic yield stresses of certain metals and alloys on loading rate has been investigated at temperatures of +20 and –196°C. In the experiments the loading rate remained constant up to the appearance of plastic strains, i.e., , where . The yield stresses of the materials and the time to the appearance of plastic strains were determined from the oscillograms representing the strain and load as functions of time.     

Original neutrino fluxes and hidden mass in the universe

The status of neutrino experiments in connection with the fundamental problem of searches for a signal from dark matter is discussed. Limits on the magnitude of the effect of dark-matter-particle annihilation in the Sun that were obtained with neutrino telescopes are presented. In particular, the first results from the NT-200 Baikal Deep Underwater Neutrino Telescope are described.     

The optical module of Baikal-GVD

In April 2015, the first cluster of Baikal-GVD was deployed in Lake Baikal and put into operation. It comprises eight strings. Each string consists of 24 optical modules. An optical module is a detection element of Baikal-GVD; it includes a Hamamatsu R7081-100 photomultiplier tube with a high quantum sensitivity. We describe the design of the optical module, the front-end electronics, and the laboratory characterization and calibration.     

Polymerization of Ferrocene in an Electrodeless High-Frequency Discharge Helium Plasma: II.1 Structure and Crystallization Dynamics of Plasmochemically Polymerized Films

The main frequencies in the IR spectra of ferrocene and plasmochemically polymerized ferrocene films obtained in the plasma of an electrodeless high-frequency discharge in mixtures of helium and ferrocene are the same. The appearance in the IR spectra of the films of weak bands is associated with partial decomposition of ferrocene molecules in the high-frequency discharge plasma.     

Organolithium and organosodium compounds of n-substituted 2-alkylbenzimidazoles

Organolithium and organosodium compounds of 1,2-dimethyl-, 1-methyl-2-ethyl-, 1-methyl-2-propyl-, and 1-phenyl-2-methylbenzimidazole, containing the metal in the alkyl group at position C(₂), were obtained by metallation. It was found that metallation can be complicated by the addition of the metalling reagent at the C=N bond of the heterocycle. It was shown that the obtained organometallic compounds can be used for the synthesis of various derivatives of benzimidazole.The calculation was performed with the standard bond lengths. A planar model was used for the carbanion.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1073–1077, August, 1986.     

Metallic films forming on the surface of alkali-halide crystals during thermal diffusion of intracrystalline immpurities

It was detected for the first time that films consisting of a transition-metal-based structure form (via thermal diffusion of intracrystalline impurities) on the surface of alkali-halide (LiF, NaF) crystals activated by transition metals Co, Ni, or Mn. The thickness, density, and composition of the films are shown to be different, depending on the heat treatment conditions. The crystals were annealed at temperatures varying from 473 to 1073 K in vacuum and air. The surface structures forming upon annealing in vacuum exhibit magnetic properties. The films were studied by optical, x-ray fluorescence, and electron spectroscopy to reveal the mechanisms of transition-metal film formation during thermal annealing.     

Synthesis and investigation of titanium diselenide intercalated with ferrocene and cobaltocene

Single crystals and polycrystals of titanium diselenide TiSe₂ intercalated with ferrocene Fe(η⁵-C₅H₅)₂ and cobaltocene Co(η⁵-C₅H₅)₂ are synthesized. The magnetic susceptibility and electrical resistivity of the intercalation compounds are measured. The results obtained demonstrate that the intercalation brings about the formation of an impurity band with a temperature-dependent width.