Qualitative estimation of the dependence of the number of energetic compounds on their oxygen coefficient

The ratio between the numbers of structural formulas of C,H,N,O-containing energetic compounds belonging to the classes of fuels (low values of the oxygen coefficientA), explosives (mediumA), and oxidants (highA values) was studied by a computer generation procedure. The number of the theoretically possible structural formulas was found to decrease rapidly on going from fuels to explosives and then to oxidants; this observation agrees with the data on the numbers of various energetic compounds currently used and proposed. The strategy of the search for new compounds with the specified properties is described in brief, and its applicability to the search for explosives and oxidants with a small (up to 12) number of atoms in a molecule is evaluated. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 7, pp. 1304–1310, July, 1998.     

Estimation of the Diffusion Coefficient of Doxorubicin Molecules in a Water Solution in the Volume of a Porous Carrier Medium

Russian Physics Journal - An experimental investigation of the phenomenon of diffusion of the solution components in nanosized pores is extremely difficult and in certain cases impossible. An...     

Preparation and properties of some derivatives of perfluoropropyl vinyl ether

Conclusions It has been shown that it is possible to synthesize phenoxy derivatives of perfluoroalkyl ethers from perfluoropropyl vinyl ether. Some reactions of the products have been studied.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2319–2321, October, 1984.     

Numerical Simulation of Plasma Flows in the Interior Cavities of Laser Fusion Targets

This paper deals with a numerical simulation and theoretical investigation of the behavior of plasma flows produced when injecting a laser beam into a target for inertial thermonuclear fusion and absorbing laser radiation in the target internal cavity. Results of two-dimensional numerical calculation are presented for laser beam interaction with the sub critical plasma contained in the gap between two coaxial shells of a laser greenhouse target. The calculations confirm the possibility of initiating a supersonic wave of electron heat conduction in the absorber of the laser greenhouse target.     

Radiation resistance of GaAs–AlGaAs heterostructures doped with isovalent and rare-earth elements

When GaAs–Si and GaAs–AlGaAs heterostructures are exposed to γ-quanta, radiation stimulated ordering is observed. However, the gettering efficiency in such systems falls for layer widths more than 1 μm. For this reason we seek effective methods of radiation resistance improvement of materials in which one would expect point radiation defects to be gettered not only at defect boundaries, but also in the active layer volume.

S.i.GaAs–s.i.Al_xGa_1−xAs–nGaAs : Te heterostructures are presented with epitaxial layers (doped with Yb or undoped), obtained by means of LPE (liquid-phase epitaxy). The electron concentration in nGaAs was found to be (1–3)×10¹⁸ cm⁻³ for widths 1–3 μm. The samples were exposed to ⁶⁰Co γ-quanta with doses of 10⁵–10⁷ rad.

Investigations of irradiated samples by means of low-temperature (4.2 K) photoluminescence have shown considerable decrease of exciton halfwidth in the boundary spectra of nGaAs : Te : Yb epitaxial layers in comparison with nGaAs : Te layer spectra. This is caused by background impurity gettering which happens on the s.i.Al_xGa_1−xAs–nGaAs heteroboundaries as well as in deformed regions in the epitaxial layer volume. Formation of such regions is caused by the difference between the covalent radii of Yb atoms and GaAs lattice atoms. The maximum effect of radiation stimulated gettering of dopants in nGaAs epitaxial layers is observed for Yb concentrations which are equal to 10⁻⁴–10⁻⁵ atomic fractions in a solution-melt.

It is determined that the deformed regions in epitaxial layer volumes and heteroboundaries could be efficient drains for point radiation defects which form under radiation exposure. The investigations carried out showed that the doping of an epitaxial layers by rare-earth impurities provides considerable improvement in forming radiation resistant III–V materials.     

Synthesis of fluoro-containing substituted 1,3,5-triazines

Conclusions By the method of acylation-cyclodehydration of imidoylamidines we have prepared 1,3,5-triazines with three different substituents, among them reactive unsaturated and nitrile groups.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 928–933, April, 1989.     

Cycloaddition of perfluorovinyl ethers to dienes

Conclusions Cycloaddition of perfluorovinyl ethers to butadiene or piperylene led to 1-vinyl- or 1-propenyl-2-perfluoroalkoxy-2,3,3-trifluorocyclobutanes as mixtures of cis and trans isomers.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 10, pp. 2372–2377, October, 1988.     

Exchange reaction of perfluoroalkyl- and perfluorooxaalkylimidoylamidines

Conclusions It was found that exchange reaction takes place between N-(perfluorobutyrylimidoyl)perfluoropropyl-amidine and N-(perfluoro-2-methyl-3-oxahexylimidoyl)perfluoro-2-methyl-3-oxahexylamidine at temperatures where their thermal condensation to triazines still does not take place.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, pp. 2784–2787, December, 1977.     

Influence of the Method of Boron Introduction on the Formation and Activity of Hydrotreatment Catalysts

Kinetics and Catalysis - Experimental data on the effect of the method of introducing boron and Ni(Co) and Mo compounds on the physicochemical properties and hydrodesulfurization activity of...