Scattering by a random field of elastic deformations in neutron-bombarded GaAs

The contribution to electron scattering due to a random field of elastic deformations produced by defects in GaAs caused by neutron irradiation is calculated. Under the assumption of smallness of the radius of correlation of the random field and the parameter values used earlier to interpret the optical absorption spectrum, the influence of this scattering mechanism on the mobility is estimated.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 51–53, June, 1987.     

Fibre-laser IR luminescence diagnostics of malignant tumours using rare earth porphyrins

To eliminate the masking effect of the background luminescence of endogenic substances in biological tissues and to increase the luminescence contrast values of malignant tumours, sarcoma-implanted mice were administered with ytterbium porphyrins instead of free porphyrin radicals. This was followed by in vivo luminescence localization of tumours using fibre-laser spectrofluorometry. The luminescence contrast values obtained reached 10-45 which is evidently not a limit.     

Novel types of boronated chlorin e6 conjugates via ‘click chemistry’

Conjugates of chlorin e₆ with closo‐dodecaborate and cobalt bis(dicarbollide) anions were synthesized for the first time in high yields using the advanced ‘click’ methodology. In vitro study on A549 human lung adenocarcinoma cells revealed that the synthesized boronated conjugates are able to penetrate and accumulate in cancer cells, but their intracellular concentration is not sufficient for effective photodynamic and boron neutron capture therapy of cancer. Copyright © 2009 John Wiley & Sons, Ltd.     

Tunnel magnetoresistance of bilayer ferromagnetic nanoparticles with magnetostatic interlayer interaction

A new method for forming submicron magnetic tunnel junctions consisting of two CoFe ferromagnetic layers separated by a dielectric TaO _x spacer is proposed. It is shown that the tunnel magnetoresistance effect can be used for studying the features of magnetization reversal of bilayer ferromagnetic nanoparticles.     

Reversible sorption of hydrogen on the novel hybrid material based on mesoporous chromium(<Emphasis Type="SmallCaps">iii</Emphasis>) terephthalate with included rhenium clusters

The interaction of mesoporous chromium(iii) terephthalate [Cr₃O(C₈H₄O₄)₃F(H₂O)₂] (MIL-101) with an aqueous solution of the anionic cluster [Re₄S₄F₁₂]⁴⁻ ({Re₄}) afforded a novel hybrid material {Re₄}@MIL-101. According to the elemental analysis data, one cavity of the nanoporous framework contains up to two-three tetranuclear rhenium clusters. The hybrid sorbent obtained reversibly absorbs up to 3.7 wt.% hydrogen at 77 K and 30 atm.     

The structure of titanium nickelide surface layers formed by pulsed electron-beam melting

X-ray structure analysis technique has been developed for a material heterogeneous over the depth. The structure of the TiNi intermetallide subjected to surface modification by an electron beam has been investigated. The following three layers differentiated in the microcrystalline structure have been singled out: (i) the external sharply textured layer 1–3 μm in thickness with a texture in the [100] B2 direction and a lattice periodicity parameter reduced by 1% in the direction of the normal, (ii) the intermediate gradient-stressed layer 10–15 μm in thickness with the texture of the initial ingot, and (iii) the original material. The crystal lattice of the surface as well as of the intermediate layer is in a state stretched along the surface and compressed along the normal to it. This lattice distortion is maximal in the surface layer and decreases towards the bulk of the material.     

Formation of extended periodic microstructures by “Point” irradiation of gold film by femtosecond laser pulses

Extended periodic microstructures are formed on a thin gold film by femtosecond laser radiation. The structure length is an order of magnitude larger than the typical size of the irradiated region. The detection of gold photoions generated in the process of the microstructuring ensures a high-sensitivity on-line diagnostics of this phenomenon.     

A monopole-dipole resonance absorber in a narrow waveguide

A sound absorber in a narrow waveguide is considered. The absorber consists of one monopole and one dipole resonator placed in a narrow pipe. The optimum parameters of the resonators that provide for the maximum absorption of acoustic power are determined. Results of an experimental study of a two-resonator absorbing system are presented. A 95% absorption is achieved.     

On Nonlinear Equations Integrable in Theta Functions of Nonprincipally Polarized Abelian Varieties

Siberian Mathematical Journal -