Simulation of sintering of low-temperature ceramic products formed by additive technology

Computer simulation methods have been applied to study the processes of low-temperature ceramics synthesis corresponding to technological processes. The simulation is performed for micron- and nanosized powders with different morphology. The synthesized composite medium has the characteristics (microlayer thickness, pore volume fraction, etc.) that reflect imperfections in the initial dispersion. The developed model allows one to examine the governing factors of physical and chemical processes in low-temperature ceramics synthesis.     

Stereoselective arylthiolation of dehydroalanine in the NiII coordination environment: the stereoinductor of choice

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Study of cascade showers generated by near-horizontal muons in the water Cherenkov detector with a dense array of optical modules

The method for reconstructing the cascade curve by the Cherenkov radiation in water of the NEVOD detector with a dense spatial array of optical modules is discussed. Cascades are generated by near-horizontal muons which are separated by the DECOR coordinate detector. The cascade curves and the cascade energy spectrum measured in an ～8000-hour measurement series are presented.     

Ta-containing oxide coatings on titanium for biomedical application

Bioinert, biocompatible, chemical-resistant oxide coatings containing Ta₂O₅, which are promising to be applied to titanium implants, were produced on titanium by plasma electrolytic oxidation in an aqueous electrolyte. An effect of formation conditions on the elemental and phase composition, thickness, and roughness of the coatings was researched. It was found that an addition of polyethylene glycol to electrolyte without affecting the elemental composition and the thickness causes a change in the porosity and an increase in the roughness of the formed oxide layer. Changing the surface arrangement may allow affecting an adhesion of biotissues to titanium implants with coatings and accumulating drugs by the coatings.     

Investigating the energy, angular, and temporal characteristics of forbush effects registered by the URAGAN muon hodoscope

The results from analyzing variations in the flux of cosmic ray muons during Forbush effects (FEs) registered by the URAGAN muon hodoscope over the period 2005–2009 are presented. The dependences of the amplitudes for reductions in the intensity of the cosmic ray muon flux on the energy of primary particles in energy ranges higher than 10 GeV were obtained. Their changes upon different phases of Forbush effect development were investigated. The local anisotropy vectors were calculated on the basis of spatial-angular variations in the muon flux. Correlations between the parameters of physical properties in the near heloiosphere related to the Forbush effects and the characteristics of muon flux variations were analyzed.     

Fluorine-containing Vinyl Ethers: I. Reactions with Carboxylic Acids

Polyfluoroalkyl vinyl ethers take up aliphatic and aromatic carboxylic acids in the presence of 0.2-5 wt% of trifluoroacetic acid at 55-105°C to give fluorine-containing hemiacetals in 60-100% yields.     

H<Subscript>2</Subscript>O/CuIn<Subscript>3</Subscript>Se<Subscript>5</Subscript> photoelectrochemical cells: Fabrication and properties

Single-phase coarse-grained CuIn₃Se₅ ingots are grown by horizontal oriented crystallization from the near-stoichiometric melt. Photosensitive structures based on the interface between these crystals and an electrolyte (H₂O) are created. It is shown that the CuIn₃Se₅ ternary compound is a direct-gap semiconductor with an energy gap Eg ≃ 1.1 eV (T = 300 K). H₂O/CuIn₃Se₅ photoelectrochemical cells seem to be promising for efficient wide-band photodetectors of natural light.