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Bazhenova, L. N.; Kirichenko, V. E.; Pashkevich, K. I.; Sereda, I. P.; Mikhailenko, V. P.
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Conclusions
1.
In the gas-liquid chromatography of microquantities of nickel β-aminovinyl-ketonates, the interphase adsorption does not introduce an appreciable contribution to the retention data.
2.
The influence of the enthalpy and entropy factors on the dissolution of fluoroalkyl-containing nickel β-aminovinyl-ketonates in stationary liquid phases was analyzed, and it was shown that entropy of solution plays a dominant role in the determination of the order of retention of these chelates on the siloxane phases, depending on the number of difluoromethylene groups in the chain.
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Levitskii, I. I.; Minachev, Kh. M.; Voronin, V. V.
Conclusions
1.
An investigation was made of a 5% aluminoplatinum catalyst in the hydrogenolysis of methylcyclopentane. A comparison of the results obtained with previously published data permits us to conclude that with respect to a number of characteristics, a 5% aluminoplatinum catalyst is similar to platinized charcoal and silica gel and differs sharply from an aluminoplatinum catalyst containing 0.3% of the metal.
2.
In aluminoplatinum catalysts, the aluminum oxide not only provides for high dispersion of the applied metal, but also determines its catalytic properties, evidently as a result of a change in the electronic state of the atoms adjoining the surface of the carrier.
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Andrianov, K. A.; Talanov, V. N.; Khananashvili, L. M.; Borodochenkova, T. G.
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Conclusions
1.
In the reactions of cyclosilazoxanes with alkali at above 100° ammonia and methane are liberated, and the curve expressing the change in viscosity has a well-defined maximum.
2.
At the first stage of the reaction the cyclic compound polymerizes with opening of the ring, which leads to increase in the viscosity of the system. At the second stage fragmentation of the polymer chains with liberation of ammonia predominates, which leads to a fall in viscosity.
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By
Saatsazov, V. V.; Khotsyanova, T. L.
Conclusions
A statistical analysis of the crystalline splittings of the35Cl NQR spectra in the series R1R2P(O)Cl (R1, R2=Alk, Ar, Hal) revealed that the error in correlating the frequencies with theσ-constants of the substituents is due mainly to the crystal effect.
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Shostakovskii, M. F.; Sidel'kovskaya, F. P.; Kolodkin, F. L.
Summary
1.
By the free-radical addition of thiols to N-vinyl and N-allyl lactams in presence of azodiisobutyronitrile 1-[2-(alkylthio)ethyl]-2-pyrrolidinones, N-2-(alkylthio)ethylcaprolactams, 1-[3-(alkylthio)propyl]-2-pyrrolidinones, and N-3-(alkylthio)propylcaprolactams were synthesized in 70–95% yield. In this reaction N-vinyl lactams are more reactive than N-allyl lactams; moreover, in each of these groups of N-alkenyl lactams, caprolactam derivatives are a little more active.
2.
By the reaction of 1-(2-chloroproyl)-2-pyrrolidinone with sodium alkyl sulfides, pyrrolidinone and 1-[2-[(ethoxycarbonyl)methylthio]propyl]-2-pyrrolidinone were synthesized.
3.
N-2-[(ethoxycarbonyl)methylthio]ethyl and N-3-[(ethoxycarbonyl)methylthio]propyl lactams are precursors in the biosynthesis of new penicillins.
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