Sulfur incompletely characterized

Incompletely Characterized Carbon Sulfides. A poorly characterized black soHd, known as carsul, occurs as a residue ia sulfur distillation or as a precipitate ia molten Frasch sulfur (12,13). Although this material may approach the composition of a carbon sulfide, it is more likely also to contain some chemically bound hydrogen and possibly other elements. Carbon—sulfur surface compounds of the formula C S, where xis greater than 4,... 

Carbon storage, of hydrogen, 23 786 Carbon sulfides, 23 621, incompletely characterized, 23 62 Carbon sulfotelluride, 24 419 Carbon-sulfur surface compounds, 23 621 Carbon tetrabromide, 4 348 Carbon tetrachloride, 6 249 acrylamide solubility in, 2 290t... 

The modification of lignins with chlorophosphazenes allows the manufacture of products characterized by flame resistance and thermal stability. This can be attributed to the aromatic structure of the lignin-phosphazene polymer as well as to the presence of such flame inhibiting elements as phosphorous, nitrogen and sulfur. Other useful properties may also result from this combination. It has previously been reported (8-13) that the modification provides crosslinked products with suitably low chlorine content. This is a consequence of incomplete substitution of the phosphazenes cycles. Additional modification of the reaction products by chemical compounds with reactive hydroxyl or amine groups reduces the unreacted chlorine content and improves product properties (8-13). Some properties of the derivatives obtained are presented in Table I. 

As with much of osmium sulfur chemistry the data are scattered and incomplete the best characterized complex is the dithioacetylacetonate complex Os(sacsac)3. 

This very interesting reaction involves the formal insertion of a sulfur atom into two unactivated CH bonds. The purified protein contains a [2Fe-2S] cluster [131]. A defined system, consisting of biotin synthase, flavodoxin, llavodoxin reductase, fructose 1,6-bisphosphate, cysteine, DTT, NADPH, ferrous ion, and SAM, capable of catalyzing the conversion of dethiobiotin to biotin has been characterized [132-134]. This system is still incomplete and gives a maximum of two moles of biotin per mole of biotin synthase. 

It is apparent that information on the reaction between sulfur dioxide and sugars in well-characterized systems is incomplete. Even less understood is the interaction of sulfur dioxide with sugars and other food ingredients in the vastly more complex systems represented by fruit and vegetable products. The intricate nature of these commodities makes it understandable that most studies have, of necessity, been empirical. Another complication results from the apparent variety of reactions induced in foods by sulfur dioxide. For example, in dehydrated foods and... 

If Q values actually reflect the primaiy medium effect of 0 , they cause that the above-mentioned melts as extremely aggressive acidic media, likely because of performance of anhydrous sulfuric acid in comparison with water (Hq -logy + = -11 In particular, such melts should completely dissolve appreciable quantities of solid oxides, e g., MgO, NiO, etc., up to 1 mol kg. For instance, MgO, which is practically insoluble in KCl-NaCl equimolar mixture (pK = 9.33 0.06 can be characterized by pK 1 (because 9.33 - 8 1) in KCl-LiCl eutectic that corresponds to the value of the solubility product of the order of 10". As for the KCl-NaCl-CaCl2 melt, the solubiUty product value should also be close to 1. On the contrary, most metal oxides slightly soluble in the KCl-NaCl melt were shown by Shapoval, Makogon and Pertchik to remain only slightly soluble in KCl-LiCl eutectic. Moreover, these oxides (NiO, CoO) are dissociated incompletely under these conditions. ... 

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