Thermal Decomposition of Sulfur Compounds. I. 2-Methyl-2-propanethiol

1952 ◽  
Vol 74 (13) ◽  
pp. 3284-3287 ◽  
Author(s):  
C. J. Thompson ◽  
R. A. Meyer ◽  
J. S. Ball
1949 ◽  
Vol 22 (2) ◽  
pp. 348-355
Author(s):  
George F. Bloomfield

Abstract At temperatures in the region of 140°, organic polysulfides undergo disproportionation resulting from thermal fission of S—S bonds and recombination of the fission products. In the presence of olefins a considerable proportion of the fission products become attached to ethylenic centers of the olefin, forming mixed mono- and polysulfides. The major part of the monosulfide product is fully saturated, hydrogen capture occurring during, or subsequent to the formation of adducts from the olefin and sulfurated fragments; unsaturation, however, appears in the polysulfide portion. The polysulfides are capable of producing monothio cross-links between the original olefinic molecules only in so far as they are able to yield up elementary sulfur to the olefin, and when the original olefin is a polyisoprene, the tendency towards the formation of a high proportion of intramolecular cyclic sulfide still further reduces the opportunity for formation of intermolecular sulfur-cross-linked products.


2016 ◽  
Vol 39 (11) ◽  
pp. 2096-2106 ◽  
Author(s):  
Natalia Olahova ◽  
Marko R. Djokic ◽  
Ruben Van de Vijver ◽  
Nenad D. Ristic ◽  
Guy B. Marin ◽  
...  

1952 ◽  
Vol 74 (13) ◽  
pp. 3287-3289 ◽  
Author(s):  
C. J. Thompson ◽  
R. A. Meyer ◽  
J. S. Ball

Author(s):  
William J. Baxter

In this form of electron microscopy, photoelectrons emitted from a metal by ultraviolet radiation are accelerated and imaged onto a fluorescent screen by conventional electron optics. image contrast is determined by spatial variations in the intensity of the photoemission. The dominant source of contrast is due to changes in the photoelectric work function, between surfaces of different crystalline orientation, or different chemical composition. Topographical variations produce a relatively weak contrast due to shadowing and edge effects.Since the photoelectrons originate from the surface layers (e.g. ∼5-10 nm for metals), photoelectron microscopy is surface sensitive. Thus to see the microstructure of a metal the thin layer (∼3 nm) of surface oxide must be removed, either by ion bombardment or by thermal decomposition in the vacuum of the microscope.


Author(s):  
A. Legrouri

The industrial importance of metal catalysts supported on reducible oxides has stimulated considerable interest during the last few years. This presentation reports on the study of the physicochemical properties of metallic rhodium supported on vanadium pentoxide (Rh/V2O5). Electron optical methods, in conjunction with other techniques, were used to characterise the catalyst before its use in the hydrogenolysis of butane; a reaction for which Rh metal is known to be among the most active catalysts.V2O5 powder was prepared by thermal decomposition of high purity ammonium metavanadate in air at 400 °C for 2 hours. Previous studies of the microstructure of this compound, by HREM, SEM and gas adsorption, showed it to be non— porous with a very low surface area of 6m2/g3. The metal loading of the catalyst used was lwt%Rh on V2Q5. It was prepared by wet impregnating the support with an aqueous solution of RhCI3.3H2O.


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