Die Isolierung und Untersuchung der Lignosulfos?uren der Sulfitzellstoffablaugen

Ohne Zusammenfassung     

A new phenol fromPinus sylvestris

Conclusions From the extractive substances of Scotch pine a phenolic compound has been isolated for which the structure of 3-hydroxy-5-methoxybenzyl alcohol has been established; it has been given the name sylvopinol.     

Azimuthal dependence of reverberation from a harmonic signal propagating in shallow water

The problem of scattering from a rough sea surface is considered for a harmonic low-frequency (200–400 Hz) acoustic signal propagating in a shallow water area. An experimental study of the azimuthal reverberation dependence is carried out on the basis of the bistatic location scheme with the use of linear phased arrays. By comparison with calculations, the formation of the frequency-angular characteristics of reverberation is investigated for various wind directions with respect to the path of acoustic signal propagation.     

Synthesis,Structure, and Chemical Transformations of 2-Chloroprop-2-en-1-yl Sulfones

A green approach was proposed for the synthesis of 2-chloroprop-2-en-1-yl sulfones in 47–94% yield. The molecular and crystal structures of 2-chloroprop-2-en-1-yl phenyl sulfone and 2-chloroprop-2-en-1-yl methyl sulfone were determined by X-ray analysis. π-Stacking interaction between the benzene ring and double bond was revealed in the crystal structure of 2-chloroprop-2-en-1-yl phenyl sulfone. Chloropropenyl sulfones were found to readily undergo dehydrochlorination to give stable allenyl sulfones and alkaline hydrolysis to produce the corresponding acetonyl sulfones. The latter can be converted to oximes by treatment with hydroxylamine hydrochloride.

     

Specific Features of Strain Dependences of Loss Modulus in Highly Stretched Elastomers

The loss modulus E″ in elastomer strips stretched by a factor of λ is studied theoretically. A small oscillating deformation is applied to these strips in the transition frequency zone between the glassy and rubbery states. The range of λ under study ranges up to ultimate extensions close to fracture. A model of E″/λ dependence in the transition frequency zone is suggested that considers the possible distortion in the local chain structure in the ultimate extension range. It is found that E″ in the range of moderate and high λ increases owing to the finite extensibility of the chains. However, upon further extension up to ultimate values, E″ decreases and a maximum appears on the E″/λ curves. These features are also confirmed experimentally.

     

Study of the mechanism of recyclization of furans into thiophenes and selenophenes in conditions of acid catalysis. 4. study of the effect of the solvent and direction of reactions of hydrolysis and recyclization of 2,5-dimethylfuran

The kinetics of hydrolysis of 2,5-dimethylfuran and its recyclization into the corresponding thiophene were investigated in water-alcohol medium W R I and 50% ethyl alcohol in the presence of HCl. It was found that the rates of these reactions are a function of both the initial concentration of the acid component and the concentration of water in the alcohol. The rate of hydrolysis is a function of the dilution of the alcohol to a greater degree than the rate of recyclization.See [1] for Communication 3.Scientific-Research Institute of Chemistry at N. G. Chernyshevskii Saratov State University, Saratov 410026. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 5, pp. 624-628, May, 1995. Original article submitted January 30, 1995.     

Interaction between polymer capsules with hydrophobic cores and a model cellular membrane at an air–water interface

Submicrocapsules have been prepared from diethylaminoethyl dextran and xanthan gum on oil cores by ultrasonic treatment. These capsules have been modified with poly-L-lysine via electrostatic adsorption. The behavior of the capsules has been investigated at an air–water interface after their introduction into the aqueous subphase. The interaction of the capsules with a 1,2-dimyristoyl-sn-glycero-3-phosphocholine monolayer formed on the water surface (model cellular membrane) has been studied both upon their introduction under the condensed monolayer and with the use of a dilute colloidal solution of the capsules as a subphase.     

Space-Frequency Interference Structure of Acoustic Fields in Oceanic Waveguides

Laws manifesting themselves in the formation of the space-frequency distribution of the intensity of the acoustic field generated by a point source of wide-band radiation are considered. Most attention is concentrated on the study of the effect of diffraction focusing on the formation of the interference structure of the acoustic field.