Measurement of the spin and temperature dependence of ddµ molecule formation rate in solid and liquid deuterium

The ddµ molecule formation rate is experimentally measured for the two hyperfine states of the dµ-atom in the temperature range of 5–30 K. Results are consistent with a preliminary measurement by the TRIUMF group and contradict theoretical predictions. The work has been performed on the JINR phasotron (Dubna).     

Synthesis of the esters of 1-alkyl-2-aminoindolyl-3-acetic acids by the kost reaction

The reaction of the esters of N-alkyl-N-phenylhydrazinocarbonylpropionic acids with phosphorus oxychloride in dioxane or with phosgene in benzene leads to the formation of the esters of 1-alkyl-2-aminoindolyl-3-acetic acids and of the corresponding N-alkyl-N-phenylaminosuccinimides.All-Russian Center for the Safety of Biologically Active Substances (ARC BAS), Kupavna, Moscow Oblast 142450. Translated from Khimiya Geterots iklicheskikh Soedinenii, No. 11, pp. 1502–1506, November, 1995. Original article submitted September 2, 1995.     

An algebraic method for investigating stability of linear normal systems of partial differential equations

In certain special classes of linear normal systems of partial differential equations, sufficient conditions for the trivial solution of the Cauchy problem to be stable can be phrased in terms of the coefficients. The determination of such classes is based on a modified method of majorants, combined with the use of n-dimensional hypercomplex numbers with associative-commutative multiplication.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 44, No. 4, pp. 480–489, April, 1992.     

Heat mass transfer in a turbulent layer above permeable membranes

The temperature and concentration fields in a boundary layer above perforated membranes are presented, and their relationship with the velocity fields given in [1] is established. Measurements of the thermal state of membranes are made with various geometric and thermophysical properties and various coolant drafts. Empirical formulas are also presented for thermal flux and temperature of the permeable walls.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 4, pp. 22–31, July–August, 1973.     

Synthesis of 1-aryl-3-(3-pyrrolyl)-5-oxopyrazoles

1-Aryl-3-(2,4-dimethyl-5-ethoxycarbonyl-3-pyrrolyl)-5-oxopyrazoles were obtained by condensation of ethyl -(2,4-dimethyl-5-ethoxycarbonyl-3-pyrrolyl)--ketopropionate with arylhydrazines. Electron-donor substituants in the aromatic ring of the arylhydrazines accelerate the cyclization of the intermediate hydrazones, whereas electron-acceptor substituents hinder cyclization.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1076–1081, August, 1983.     

Multifunctional high-temperature D5 MAI and M1 MAI coatings

Theoretical and practical aspects of creating reliable protective coatings of the heat-stressed structural components of hypersonic aircrafts for operating in high-enthalpy oxygen-containing gas flows are discussed. The main mechanisms of disintegration of coating under these conditions were identified and criteria for estimating their contributions. The danger of oxidation the material protected by the coating is largely associated with the formation of open pores and cracks in the coating. A new physicochemical model of a heterophase coating was proposed, which was used to create a number of materials for manufacturing layered coatings for applying onto high-melting alloys and C/C, C/SiC, and Si/SiC composite materials. These coatings are capable of effectively protecting for gas corrosion and erosion within the temperature range covered, 300–2100 K. When exposed to high temperature, the microcomposite material applied is capable of self-organizing into a multilayer multifunctional coating with a low catalytic activity, K _w ～ 3 m/s, and a rather high emissivity, ? ≈ 0.7–0.8. The coating is is a multilayer nanostructure with a thickness of individual layers of 10–1000 nm. The coating is capable of fast self-healing of micro- and macrodefects. The coating were tested when applied onto niobium-based alloys and carbon materials under conditions imitating the reentry of a space vehicle into the dense atmosphere.     

Synthesis and some transformations of pyrroles with aliphatic acyl substituents

A number of higher aliphatic pyrryl ketones were synthesized. It is shown that a carbethoxy group in the 5 position of the pyrrole ring relatively weakly deactivates the 3 position of the ring to electrophilic attack during Friedel—Crafts acylation but hinders this reaction considerably when it is in the adjacent 4 position. The oxidation of the -methyl group in a series of pyrryl ketones and the corresponding alcohols was studied.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 1, pp. 27–30, January, 1973.     

Heterocyclization of N-propionylaminoindoline

Treatment of N-propionylaminoindine with a solution of phosgene in benzene gives the 1-[(indolin-1-yl)imino]propyl ester of 7-(1-cyanoethyl)indoline-1-carboxylic acid. The structure of the compound was proved using¹H and¹³C NMR spectroscopy.All-Russian Science Center for the Safety of Biologically Active Materials, Staraya Kupavna, Moscow Region 142450. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 2, pp. 168–170, February, 1995. Original article submitted January 11, 1995.