Depth concentrations of deuterium ions implanted into some pure metals and alloys

Pure metals (Cu, Ti, Zr, V, Pd) and diluted Pd alloys (Pd-Ag, Pd-Pt, Pd-Ru, Pd-Rh) were implanted by 25-keV deuterium ions at fluences in the range (1.2–2.3) × 10²² m⁻². The post-treatment depth distributions of deuterium ions were measured 10 days and three months after the implantation by using Elastic Recoil Detection Analysis (ERDA) and Rutherford Backscattering (RBS). Comparison of the obtained results allowed us to make conclusions about relative stability of deuterium and hydrogen gases in pure metals and diluted Pd alloys. Very high diffusion rates of implanted deuterium ions in V and Pd pure metals and Pd alloys were observed. Small-angle X-ray scattering revealed formation of nanosized defects in implanted corundum and titanium.     

Pd-Catalyzed asymmetric transformations involving P*-mono- and P*,N-bidentate diamidophosphites derived from (2S,3S)-N 2,3-dimethyl-N 1-phenylpentane-1,2-diamine

The synthesis of new P*-mono- and P*,N-bidentate diamidophosphites, containing 1,3,2-diazaphospholidine rings formed starting from (2S,3S)-N ²,3-dimethyl-N ¹-phenylpentane-1,2-diamine, is described. Comparison of their efficiency in the Pd-catalyzed enantioselective allylation with (E)-1,3-diphenylallyl acetate showed that up to 97% ee was reached in the reaction involving dimethyl malonate as a C-nucleophile. The Pd-catalyzed desymmetrization of N,N′-ditosyl-meso-cyclopent-4-ene-1,3-diol biscarbamate gave up to 61% ee.     

Determination of oxygen in bismuthate single crystals

An improved procedure for determining oxygen in single crystals was developed. The procedure was tested on samples prepared from stoichiometric BaBiO₃ by thermal treatment in a controlled medium. The error of the procedure is about 0.5 mol%.     

Heterophase inclusions and dissolved impurities in Ge25Sb10S65 glass

The impurity content and microhomogeneity of Ge₂₅Sb₁₀S₆₅ glass samples, prepared by direct synthesis from elements, were investigated. It was shown that the increase in temperature of synthesis of the glass-forming melt resulted in the increase of the content of impurities of H, Na, Al, Si, K, Ca and transition metals in the prepared glasses. The glasses from the melt, subjected to chemical-distillation purification, were characterized by the low content of gas-forming impurities and the increased content of Al, Si and Cl. The glasses contained heterophase impurity inclusions mainly consisting of SiO₂, and their concentration and size depended on the conditions of glass preparation. The impurity content in the purest glasses was as follows: oxygen – <0.5 ppm wt, carbon – <5 ppm wt, hydrogen – 0.1 ppm wt, Si – <1 ppm wt, transition metals – <0.25 ppm wt, heterophase impurity inclusions with sizes larger than 80 nm – <10² cm³. It was shown that heterophase impurity inclusions behaved as the centers of glass crystallization.     

Synthesis and Chemical Transformations of 7-Hydroxybicyclo[3.3.1]nonane-3-carbohydrazide

Russian Journal of Organic Chemistry - The reaction of 4-oxahomoadamantan-5-one with hydrazine gave (3-exo,7-endo)-7-hydroxybicyclo[3.3.1]nonane-3-carbohydrazide. The latter was reacted with...     

New oxazoline-containing phosphoramidite ligand for palladium-catalyzed asymmetric allylic sulfonylation

New chiral oxazoline-containing phosphoramidite was synthesized and its complex formation with rhodium(i) and palladium(ii) was examined. The new ligand is a highly efficient chiral inductor (ee up to 92%) in palladium-catalyzed asymmetric sulfonylation of 1,3-diphenylallyl acetate with sodium p-toluenesulfinate.     

Generation of a continuum and stimulated Raman scattering harmonics during scattering of electromagnetic radiation of relativistic intensity

A theory of the propagation instability of plane, monochromatic, circularly polarized electromagnetic waves of relativistic intensity in matter is developed for a spatially three-dimensional geometry including arbitrary polarization of the scattered radiation. Harmonic generation owing to striction and relativistic nonlinearity is examined, as well as scattering owing to electron recoil, the decay instability of the harmonics with formation of scattered electromagnetic waves (Stokes components of the stimulated Raman scattering and plasmons), the interaction of electromagnetic waves in the plasma (antistokes stimulated Raman scattering), and the generation of a radiative continuum. The transition of the three-dimensional theory to a one-dimensional problem in the nonrelativistic limit is discussed. Zh. éksp. Teor. Fiz. 113, 2034–2046 (June 1998)