Materials most probable structures from

The isomerization of open-chain alkanes with more than six carbon atoms gives isobutane as the main product, together with disproportionated materials, even though the reaction proceeds by the monomolecular pathway [144]. On the other hand, for cyclic alkanes the monomolecular process with preservation of the cyclic structure seems to be the most probable, judging from the results for cyclohexane. The absence of isobutane in the products indicates that the reaction path does not involve open-chain intermediate species. Therefore, it is of interest to try cycloalkanes larger than cyclohexane for clarification of the reaction mechanism along with the catalytic action of S04/Zr02. 

It is doubtful, based on other efforts, that alternating copolymer is produced. The material most probably contains some poly(phenylacetylene) blocks. Since MA forms a CTC with poly(phenylacetylene) and copolymerization of the two materials can occur, the product from phenylacetylene-MA copolymerization could have a very complex structure. ... 

Until recently, most of the chemical research on the contents of these structures was directed at the identification of the constituents of castoreum. In the late 1940s Lederer [72, 73] identified 36 compounds and some other incompletely characterized constituents in castoreum of uncertain origin. Other constituents were subsequently identified in the material [74-77]. In a reinvestigation aimed specifically at the phenol content of the material, Tang et al [69] identified 10 previously unreported phenols in the castoreum from the North American beaver, Castor canadensis. Of the 15 phenols reported elsewhere, only five were confirmed in this analysis, in addition to 10 phenolic compounds that were not reported elsewhere. It was concluded that the 10 previously identified phenols that were not found in the study by Tang et al. were either absent or were not volatile enough to be detected by the methods employed. This was most probably because a relatively low maximum column temperature of only 210 °C was employed in the GC-MS analyses. The compounds identified by Lederer,... 

A wide popularization of the social use of MDMA occurred in 1984-1985 and, with the reported observation of serotonin nerve changes in animal models resulting from the administration of the structurally similar drug MDA, an administrative move was launched to place it under legal control. The placement of MDMA into the most restrictive category of the Federal Controlled Substances Act has effectively removed it from the area of clinical experimentation and human research. The medical potential of this material will probably have to be developed through studies overseas. 

Allophane, in any abundance, is most commonly formed from volcanic material although it can presumably form from any alumino-silicate minerals and indeed is probably present as a transitory stage in the alteration of any material to a clay mineral if any significant structural re-arrangement is required. In its most pure form it occurs as veins and incrustations. Most analyses (Table LXXII) are of samples from this type, of deposit. In volcanic soils (Japan, Australia, N.W.U.S., etc.) where allophane is abundant it is usually intimately mixed with halloysite and collection of... 

However, most of these attempts were found unsuccessful. This is mainly due to the fact that the mechanisms and processes responsible for the low photoresponse of hematite are far from being clearly understood. A deeper understanding of the semiconducting properties of this material is needed, such as its surface structure and a better description of the hematite/electrolyte interface. Extensive knowledge is also required to understand the photoelectro- chemical behavior of hematite and the kinetics involved in the photo-oxidation of water. Finally, for effective oxidation of water an efficient catalyst must most probably be coated onto the surface of hematite. 

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