Earlier investigations

The economics of the various methods that are employed to sequence multicomponent columns have been studied. For example, the separation of three-, four-, and five-component mixtures has been considered (44) where the heuristics (rules of thumb) developed by earlier investigators were examined and an economic analysis of various methods of sequencing the columns was made. The study of sequencing of multicomponent columns is part of a broader field, process synthesis, which attempts to formalize and develop strategies for the optimum overall process (45) (see Separation systems synthesis). 

The discovery of oxygen is generally credited to C. W. Scheele and J. Priestley (independently) in 1773-4, though several earlier investigators had made pertinent observations without actually isolating and characterizing the gas. Indeed, it is difficult to ascribe a precise meaning to the word discovery when applied to a substance so ubiquitously present... 

A. Werner (Zurich) work on the linkage of atoms in molecules which has thrown new light on earlier investigations and opened up new fields of research especially in inorganic chemistry. 

Earlier investigations have shown that powerful antispasmodic activity occurs in various basic esters of a-substituted thienylglycolic acids, thienylacetic acids, and thienylpropionic acids of the general type (256), (cf. reference 5 for details). One such compound, the... 

In earlier investigations chain ends were suggested to be important initiation sites for dehydrochlorination. Provided there are no transfer reactions during polymerization, at least half the polymer chain ends will carry initiator fragments. In practice, transfer reactions swamp the normal termination processes and <30% of the chain ends carry initiator residues [59]. 

Earlier investigators employed strong bases (sodium hydroxide, potassium hydroxide) or platinum on asbestos to... 

Note Earlier investigators such as Kast, Hess, Vennin, Burlot and Lecorche regarded this test as being indicative of relative brisance Refs 1) C.E, Munroe J.E. Tiffany, USBur-Mines Bull 346 (1931) 2) LeRoy V. Clark,... 

Among the additional data examined, the only non-normal characteristics found were for some of the results in (M10), which again, as in the earlier investigation (M4), apply to 19-rod bundles with wire-wrap supports. The consistent pattern that now seems to be emerging is that it is only the use of wires wrapped around the rods that causes nonnormal characteristics. It seems that the addition of a wrap around the complete bundle, as was the case for test sections No. 10 and 11 in Table V, prevents the nonnormal characteristics from appearing. 

Remes et al. (1976) also investigated the kinetics of the N-azo coupling of nine a-amino acids. They are aware of earlier investigations in which the major products were pentaz-1,4-dienes, but they claim that under their reaction conditions (pH 8.00-10.25, thirty-fold excess of amino acid) only the triazenes are formed. The rates were found to be first-order with respect to diazonium ion which is consistent with their conclusion however, in the opinion of the present author the results suggest a significant (say, 10%) contribution of pentazdiene formation to the total rate process. No significant correlation was found between the rate constants and the acidity constants of the nine amino acids. 

Methyl Azide.—In our earlier investigation of methyl azide2 it was concluded that the molecules contain a linear azide group with dimensions corresponding to resonance between the... 

The reasons of this behaviour were soon discovered by Schulz team29). One was purely technical. Under the conditions prevailing in the earlier experiments of Schulz and Lohr the polymerization was too slow for employment of the flow technique adopted by the authors in their earlier investigation, but too fast for the conventional batch technique. Development of a stirred reactor allowing studies of reactions with half-lifetime as short as 2 sec eliminated this difficulty 30). 

The mechanism of this reaction adopted by earlier investigators was... 

A number of summaries of early work as well as recent successes of the examination of higher plants as sources of antimicrobial agents have appeared (1-4). Many of the earlier Investigators In the field used strains of microorganisms as bloassay organisms... 

On the basis of our kinetic results, our heats of oxidation mentioned above, independent heats of total combustion (Yan, H-k. Hepler, L.G. to be published), our chemical analyses, and the results of earlier investigations by others (11-15), we have developed a chemical model or picture of the dry oxidation process as follows. 

Aside from substitutions of 58 with different ligands, the easy access to reactive 34a was also an important result of this study, although this compound had already been the subject of an earlier investigation [38], where it had been synthesized by the traditional approach of substituting two COs and one halide of 32 in refluxing acetonitrile. Two of the acetonitrile ligands are readily substituted by two phosphines, confirming the assumption in [39] that the intermediate for the formation of 59 occurs via 34a. 

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