Organic and Inorganic Compounds Compared

The use of the prior chemical information allows a dramatic reduction of the number of DOFs necessary to describe the structure, both for organic and inorganic compounds, compared with the description in terms of atomic coordinates. Generally reductions can be obtained of a factor 2 for inorganic structures and by a factor of at least 3 for organic ones." Moreover, the use of internal coordinates greatly reduces the number of generated trial structures, since only the chemically plausible ones are explored. 

The membranes used are typically composed of cross-linked silicones and are suitable for on-line monitoring of volatile organic and inorganic compounds [93-94]. An alternative material is microporous PTFE, which has more rapid responses as well as lower selectivities and higher fluxes of the mobile phase compared to nonporous silicone membranes. More recently, developments in membrane introduction systems include the use of liquid membranes composed, for example, of a polyphenyl ether diffusion pump fluid [95-96]. This membrane has the advantage that it can take any desirable analyte and the selectivity can be modified using appropriate reagents. 

The chemistry of boron-nitrogen compounds is extremely rich and varied, and much of the evolution of this field derives from attempts to obtain compounds both electronically and stmcturally comparable with well-known organic molecules. In addition, a great deal of effort has been devoted to establishing reactivity parallels between the isoelectronic/isostructural organic and inorganic compounds. Some known isoelectronic/isostractural compound pairs are summarized in Figure 1. 

Sulfur tetrafluoride is very stable when compared to the lower sulfur fluorides. It can be stored at room temperature for an indeflnite period of time. It is very reactive and is valued as a selective fluorinating agent for both organic and inorganic compounds. Its remarkable fluorinating ability has been the subject of recent reviews. ... 

Tables 6 and 1 compare the effects of several organic and inorganic compounds on the lysinoalanine and lysine contents of alkali-treated wheat gluten and soybean protein. These results show that all these compounds partly inhibit lysinoalanine formation. The extent of inhibition may vary from protein to protein and should be related to both the content and reducibility of the disulfide bonds (Friedman, 1978a Finley et al., 1978 a,b Masri and Friedman, 1982).

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