The pre‐separation of oxygen containing compounds in oxidised heavy paraffinic fractions and their identification by GC‐MS with supersonic molecular beams.

The heavy petroleum fractions produced during refining processes need to be upgraded to useable products to increase their value. Hydrogenated heavy paraffinic fractions can be oxidised to produce high value products that contain a variety of oxygenates. These heavy oxygenated paraffinic fractions need to be characterised to enable the control of oxidation processes and to understand product properties. The accurate identification of the oxygenates present in these fractions by electron ionisation (EI) mass spectrometry is challenging due to the complexity of these heavy fractions. Adding to this challenge is the limited applicability of EI mass spectral libraries due to the absence of molecular ions from the EI mass spectra of many oxygenates. The separation of oxygenates from the complex hydrocarbon matrix prior to high temperature GC‐MS (HT‐GC‐MS) analysis reduces the complexity of these fractions and assists in the accurate identification of these oxygenates. Solid phase extraction (SPE) and supercritical fluid chromatography (SFC) were employed as prefractionation techniques. GC‐MS with supersonic molecular beams (SMBs) (also named GC‐MS with cold‐EI) utilises a SMB interface with which EI is done with vibrationally cold sample compounds in a fly‐through ion source (cold‐EI) resulting in a substantial increase in the molecular ion signal intensity in the mass spectrum. This greatly enhances the accurate identification of the oxygenates in these fractions. This study investigated the ionisation behaviour of oxygenated compounds using cold‐EI. The prefractionation by SPE and SFC and the subsequent analysis with GC‐MS with cold‐EI were applied to an oxygenated heavy paraffinic fraction.     

Compromise values in cooperative game theory

Summary The aim of this paper is to give a survey on several well-known compromise values in cooperative game theory and its applications. Special attention is paid to the τ-value for TU-games, the Raiffa-Kalai-Smorodinsky solution for bargaining problems, and the compromise value for NTU-games.     

α,β-unsaturated sulfenyl chlorides

Conclusions A method has been developed for the preparation of perfluorinated,-unsaturated sulfenyl chlorides, and their reactions with basic reagents and Lewis Acids have been studied.For a previous communication, see [1].Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 5, pp. 1123–1130, May, 1982.     

Influence of structural factors on stability of fluorine-containing metastable enols

Conclusions New metastable enols, perfluoro-2-penten-2-ol and 3-chloroperfluoro-2-buten-2-ol, were synthesized. Structural factors were found which impart the kinetic stability to the enol forms of polyfluorine-containing ketones.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 621–625, March, 1983.     

An assessment of coherent coupling through radiation fields in time varying slab waveguides

This paper presents an analytical methodology for analysing two-dimensional, dielectric slab waveguides where the guiding region is subject to abrupt and arbitrary temporal changes in permittivity. The methodology solves Maxwell’s equations in the frequency domain and recovers the solutions for the guided and radiation fields in the time domain using the Laplace transformation (LT). Explicit separation of the complete field solution into a set of guided modes and a radiation field continuum provides a clearer insight into the transient effects present in time-varying dielectric waveguides. In particular, the method is used to assess and quantify the impact of coherent radiation field coupling for arbitrary time variation of the waveguide permittivity.     

Lipids and Lipophilic Components of the Aerial Part of Daucus sativus

The benzene extract of the aerial part ofDaucus sativusis analyzed. Sterols, aliphatic alcohols and their esters, triterpenes, and isoprenes make up >50%% of the extract mass. Carotenoids, -tocopherol, and other biologically active substances are also observed