Structure,composition, and physicomechanical characteristics of tantalum diboride films

The effect of a bias potential applied to the substrate on the structure formation, substructural characteristics, and physicomechanical properties of tantalum diboride nanocrystalline films obtained by the method of nonreactive high-frequency magnetron sputtering has been investigated. It has been shown that the sign and magnitude of the bias potential exert a substantial influence on the structure, composition, and physicomechanical properties of arising coatings. Upon the application of a positive bias potential to the substrate, textured films with a columnar structure, whose greatest hardness was ～45 GPa and the elasticity modulus was only moderate, ～350 GPa, have been obtained. Upon the application of a negative bias potential to the substrate, the amorphous cluster films with a hardness of ～11.5 GPa and an elasticity modulus of ～144 GPa were condensed.     

Specific recognition of HLA-E, but not classical, HLA class I molecules by soluble CD94/NKG2A and NK cells

The CD94/NKG2 receptors expressed by subpopulations of NK cells and T cells have been implicated as receptors for a broad range of both classical and nonclassical HLA class I molecules. To examine the ligand specificity of CD94/NKG2 proteins, a soluble heterodimeric form of the receptor was produced and used in direct binding studies with cells expressing defined HLA class I/peptide complexes. We confirm that CD94/NKG2A specifically interacts with HLA-E and demonstrate that this interaction is dependent on the association of HLA-E with peptide. Moreover, no interaction between CD94/NKG2A and classical HLA class I molecules was observed, as assayed by direct binding of the soluble receptor or by functional assays using CD94/NKG2A+ NK cells. The role of the peptide associated with HLA-E in the interaction between HLA-E and CD94/NKG2A was also assessed. All class I leader sequence peptides tested bound to HLA-E and were recognized by CD94/NKG2A. However, amino acid variations in class I leader sequences affected the stability of HLA-E. Additionally, not all HLA-E/peptide complexes examined were recognized by CD94/NKG2A. Thus CD94/NKG2A recognition of HLA-E is controlled by peptide at two levels; first, peptide must stabilize HLA-E and promote cell surface expression, and second, the HLA-E/peptide complex must form the ligand for CD94/NKG2A.     

Estimating the total error for a distributed group standard for time and frequency

Studies have been made on the systematic and random errors in the group frequency and time scale for a distributed group standard for the units of time and frequency. A new approach has been devised for calculating the total error of secondary standards. __________ Translated from Izmeritel’naya Tekhnika, No. 6, pp. 24–26, June, 2008.     

Experience with construction and operation of residential buildings on shell-foundations in Igarka

Translated from Osnovaniya, Fundamenty i Mekhanika Gruntov, No. 3, pp. 4–7, May–June, 1990.     

Dependence of the frictional coefficient on the antifrictional-component concentration in the working layer of a slip bearing

We know that variation in the antifrictional-component concentration affects the frictional coefficient. The relation between factors affecting the frictional properties in the production of antifrictional materials is considered in a complete factorial experiment.     

Thermodynamics of the Chemical Vapor Deposition of Carbides in the System TaBr5–CCl4–Cd

Thermodynamic analysis of the chemical vapor deposition (CVD) of tantalum carbides in the TaBr₅–CCl₄–Cd system is carried out. The equilibrium composition in the system is calculated as a function of temperature and ratios of reagents. The optimal CVD conditions for tantalum carbides with particular deviations from stoichiometry are assessed.