Sulfur composition, grain

Results. AES analysis of impact fracture surfaces on nickel showed considerable spread in sulfur composition at grain boundaries as shown in Fig. 2. The composition varied from approximately 0.04 to 0.20 monolayers on the sample heated to 1100°C for one hour and 0.15 to 0.25 monolayers on a sample that had received additional heating at 600°C for 240 hours. The additional heat treatment shifted the average grain boundary composition by nearly 0.1 monolayer of coverage. 

Again because of its high volatility, sulfur is relatively undepleted from interstellar gas by condensation in interstellar grains, so that its isotopic composition has been pardy measured by radioastronomers, who detect emission lines from the molecule CS in the interstellar medium. By comparing the rotational transitions of 13C/32S with those of 12C/34S the interstellar isotopic ratio has been found for sulfur (see 34S, Anomalous isotopic abundance). 

The isotopic composition of sulfur in individual presolar grains has not yet been measured owing to the very small concentration of S in those grains. 

Materials Used. The sulfur used was obtained from the refinery and was 99.9% pure. As for the grain form, gravel as spherical material and crushed stone (granulit, basalt) as sharp grain material were used as aggregates. In mineral composition, granulit is an acidic rock, but basalt, on the other hand, consists mainly of basic mineral components. 

Grain compositions built up according to sieve line 6, n — 0.3, still have a somewhat lower void space than those built up according to sieve line 5. Because of the high filler content (26%) the quantity of sulfur which is necessary to glue the grains must be increased overpropor-tionally, as compared with the somewhat lower void space, to obtain workable mixtures (Table IV). 

Granulit and basalt were used as aggregates. The grain composition was based on sieve line 4 and 5. The respective quantities of sulfur corresponded to those which were used with unmodified sulfur concrete mixtures (16). 

The major-element compositions of 200 chondritic IDPs were measured by EDS (Table 1 and Figure 12). All of the particles were identified as extraterrestrial because they have approximately chondritic compositions or consist predominantly of a single mineral grain like forsterite or pyrrhotite (commonly found within chondritic IDPs) 37% of the particles are CSIDPs, 45% are CP IDPs, and 18% IDPs composed predominantly of a single mineral. Table 1 summarizes the compositions of the IDPs. Within a factor of 2 the abundances of oxygen, magnesium, aluminum, sulfur, calcium, chromium, manganese, iron, and nickel are approximately chondritic. CP IDPs are a closer match to Cl carbonaceous chondrites than CS IDPs, and they are closer to Cl bulk than to Cl... 

Numerous reviews are in the literature on the fermentation-derived components of distilled spirits. Over 280 components have been identified in whiskies(25) and over 400 components have been found in rum(26). The conditions of fermentation and distillation determine the concentration of volatiles. For example the concentration and composition of trace sulfur compounds in grain spirits reflects the manner in which the distillation was carried out. No attempt will be made to compile the complete list of compounds identified to date. Rather, several newly identified components made possible by the recent advances in gas chromatography/mass spectrometry will be reported. 

The gas compositions are characterized by low carbon dioxide and high carbon monoxide contents. In the high output run (Test 71) the calorific value of the gas was unaffected, and the organic sulfur content was higher than expected Lurgi gas usually contains less than 10 grains/100 cu. ft. 

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