Integral intensities of the absorption bands of the skeletal vibrations of substituted furocoumarins

Conclusions The IR spectra of 5- and 8-hydroxyfurocoumarins and their esters, 5,8-disubstituted furocoumarins containing hydroxyl, methoxyl, and alkoxyl groups, and 4,5-dihydrofurocoumarins differ with respect to the intensity and number of the bands in the 1630–1500 cm^–1 region of the spectrum. The integral intensities of the absorption bands in this frequency region differ markedly in the derivatives mentioned.Khimiya Prirodnykh Soedinenii, Vol. 5, No. 5, pp. 355–359, 1969     

Structure of “furfuramide” and “furfurine”

The structures of ,-bis(furfurylideneimino)silvan (furfuramide or N,N'-difurfurylidene-2-furanmethanediamine) and the product of its thermal cyclization 2,4,5-tris (-furyl)-2-imidazoline (furfurine) were confirmed by comparison of the IR, UV, ¹H and ¹³C NMR, and mass spectra. It is shown that acetylation of the latter with acetic anhydride in the case of heating of the reagents without a solvent or in pyridine takes place with opening of the imidazoline ring and leads to the formation of 1,2-bis(-furyl)-1-acetamido-2-(-furoylamido)ethane.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 11, pp. 1461–1464, November, 1978.     

Modified relations for calculating the dielectric constant of barium–strontium titanate nanofilms

The results of measuring the capacitances of planar capacitors are used to calculate the dielectric constants of barium–strontium titanate nanofilms. An expression is derived to calculate an adjustable coefficient to obtain adequate dielectric constants for 20-nm-thick ferroelectric films. The field of applicability of the adjustable coefficient is determined.     

Bound states of two-particle cluster operator

Moscow State University. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 79, No. 2, pp. 163–179, May, 1989.     

Catalytic hydrogenation of furfurylideneacetone

The stepwise character of the hydrogenation of furfurylideneacetone on a Raney nickel catalyst at 50° C and atmospheric pressure was investigated. It is shown that the intermediate-1-(-furyl)-3-butanone — is primarily hydrogenated to 1-(-tetrahydrofuryl)-3-butanone.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 291–284, March, 1972.     

Estimating probabilities for sums of independent random vectors

An estimate is made for the probability of occurrence of the value for a sum of independent, identically distributed, random s-dimensional vectors in different families of spheres.Translated from Matematicheskie Zametki, Vol. 7, No. 2, pp. 217–221, February, 1970.     

CNTFET based voltage differencing current conveyor low power and universal filter

Analog Integrated Circuits and Signal Processing - This paper presents carbon nanotube field effect transistor (CNTFET) implementation of voltage differencing current conveyor (VDCC). We propose...     

An algorithm for solving a two-person game with information transfer

An algorithm for solving a two-person game with information transfer is proposed. The algorithm is based on a special linear programming problem. An example is given.     

Soluble polysaccharides of Rhodotorula flava

Conclusions 1. Xanthalin has been shown to have the structure of 2, 2-dimethyl-3, 4,-diangeloyloxy-3, 4-dihydropyrano-5, 6:6, 7-coumarin on the basis of the preparation of a number of derivatives and cleavage products.2. The following products of the alkaline hydrolysis of xanthalin have been isolated and characterized for the first time: (±)-3, 4-dihydroxy-3, 4-dihydroxanthyletin (isokhellactone), C₁₄H₁₄O₅, with mp 213–215° C and (–)-trans-3-hydroxy-4-methoxy-3, 4-dihydroxanthyletin (isomethylkhellactone, C₁₅H₁₆O₅, with mp 136.5–138° C and [] _D ²⁰ –47.7 (ethanol).Khimiya Prirodnykh Soedinenii, Vol. 6, No. 1, pp. 14–19, 1970