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Reformatsky reactions of methyl 1-bromocyclohexanecarboxylate and methyl 1-bromocyclo-pentanecarboxylate with 2-aryl-2-oxoacetaldehydes involve both carbonyl groups of the latter and result in formation of 3a-aryl-3,3 : 6,6-bis(pentamethylene)- and 3a-aryl-3,3 : 6,6-bis(tetramethylene)tetrahydrofuro-[3,2-b]furan-2,5-diones. The reaction with 2-(2,4-dimethylphenyl)-2-oxoacetaldehyde gives acyclic products, methyl 1-[1-hydroxy-2-(2,4-dimethylphenyl)-2-oxoethyl]cyclohexanecarboxylate and methyl 1-[1-hydroxy-2-(2,4-dimethylphenyl)-2-oxoethyl]cyclopentanecarboxylate, while with benzil methyl 1-(4-hydroxy-1-oxo-3,4-diphenyl-2-oxaspiro[4.5]dec-3-yl)cyclohexanecarboxylate and methyl 1-(4-hydroxy-1-oxo-3,4-diphenyl-2-oxaspiro[4.4]non-3-yl)cyclopentanecarboxylate are obtained.

The drying conditions of technical yarn on a PN-300-IZ machine, where the yarn has been prepared from spinnerets having 2200 holes, has been investigated.

The fractional composition of alkali cellulose after degradation has been investigated. It has been found that different lots of alkali cellulose are not identical in molecular weight distribution; there are significant fluctuations in content of fractions. Introducing cellulose from hot refining into the technological mix increases the nonuniformity of the alkali cellulose with respect to fractional composition. Nonuniformity of the alkali cellulose in fractional composition causes difficulties in technological processing and is connected with polydispersity of the original cellulose.