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[en] Data concerning the reactions of phosphorus ylides with acyl chlorides that occur by different pathways depending on the nature of the ylide or acyl chloride and on the reaction conditions are summarised and systematised. The products of these reactions are of interest as building blocks for the synthesis of other classes of compounds.

[en] The ionization constants of fluorine-containing monothio-β- diketones and β-aminovinylketones with aminogroup near carbon, bonded with fluoroalkyl substituent, are determined spectrophotometrically. The non-inductive effect of the long fluoroalkyl substituents on the ionization constants of monothio-β-diketones is established and the absence of the effect for β-aminovinyl- ketones is shown. Sulphur atom substitution of oxygen of carbonyl group, bonded with non-fluorated substituent decreases the value of pKsub(a) by 2-3 units, while the introduction of nitrogen atom instead of oxygen of carbonyl group, bonded with fluorated substituent, increases them by 7-8 units. The equation, connecting pKsub(a) of fluorine-containing monothio-β-diketones with pKsub(a) of the corresponding β-diketones, is presented

[en] The temperature dependence of the low-energy electron attachment and autodetachment processes for c-C₄F₆ in a N₂ buffer gas has been studied in the temperature, T, range of 300 to 600 K and the mean electron energy, <ε>, range from 0.19 to 1.0 eV. The low-energy electron attachment rate constant for c-C₄F₆ shows only a slight dependence on gas temperature. In contrast, the autodetachment frequency increases by more than four orders of magnitude when T is increased from 300 to 600 K. This increase in autodetachment is due to the increase in the internal energy content of the c-C₄,F₆^- anion with increasing T. The autodetachment process under consideration is a heat-activated process and has an activation energy E* of 0.24 eV. Significance of these results to gaseous dielectrics is indicated

[en] Fluid flow of the mixture lubricant refrigerant is visualized by neutron radiography. Dynamic images obtained with neutrons allow the examination of multiphase mixtures in working conditions for the selection of lubricants adapted to new refrigerants less harmful for the environment

[en] The work done at the Institute for Hot Atom Chemistry is concerned with research and development in the field of nuclear fuel reprocessing. The activities are guided by the aims of the planned back end fuel cycle facility. They are performed in contact with the companies DWK, KEWA and GWK within the scope of the projects reprocessing and waste management and fast breeder development. The Institue consists of the following divisions: extraction chemistry and plant operation; process analyzing; chemical process and apparatus development; dissolver and waste gas treatment; process control and automation; organic analysis; basic research. (orig./RB)

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[en] Theoretical method for the calculation of group electric negativities of substituents (I, in particular) based on a previously developed model of inductive effect is suggested. The approach permits calculating χ values on the basis of fundamental physical and geometrical parameters characteristic of the atoms substituent and features a simple and practicable mathematical instrument. 25 refs.; 2 tabs