Promotional methods, comparison

Once the FBA has been identified, ultraviolet absorption spectroscopy affords a rapid and accurate method of quantitative analysis. Care must be taken when interpreting the spectra of stilbene-type compounds, since turns to cis isomerisation is promoted by ultraviolet radiation. Usually, however, a control spectrum of the turns isomer can be obtained before the compound undergoes any analytically significant isomerisation. FBAs are often marketed on the basis of strength comparisons determined by ultraviolet spectroscopy. 

It was claimed that this model helps to explain earlier catalytic results using Cu-Ni alloys, but comparisons with alloys in granular, or other massive form, are difficult. The available catalytic results on Cu-Ni alloys show that the method of preparation of the catalyst can have a profound influence upon the observed activity pattern. The promoting effect on the catalytic activity, caused by cooling in hydrogen rather than in vacuum... 

Comparison of promoted alkaline-earth oxide catalysts prepared through evaporation and sol-gel methods by their catalytic performance in propane oxidative dehydrogenation... 

In comparison with culture-dependent procedures, culture-independent methods are more sensitive and have an increased potential to survey the diversity of antibiotic resistance genes in the environment. A weakness of these methods is the impossibility to elucidate about the bacteria in the community that host specific resistance determinants. On the other hand, the possibility to explore the genetic environment (mobile element, associated genes, promoter, etc.) in which the resistance determinant is integrated offers relevant clues about the gene transfer potential and gene acquisition history. 

Marayama, H., Tanaka, T. Williams, GM. (1990) Effects of the peroxisome proliferator di(2-ethylhexyl)phthalate on enzymes in rat liver and on carcinogen-induced liver altered foci in comparison to the promoter phenobarbital Toxicol. Pathol., 18, 257-267 Matsushima, T, Muramatsu, M. Haresaku, M. (1985) Mutation tests on Salmonella typhimurium by the preincubation method. Prog. Mutat. Res., 5, 181-186 Matthews, E.J., DelBalzo, T. Rundell, J.O. (1985) Assays for morphological transformation and mutation to ouabain resistance of Balb/c-3T3 cells in culture. Prog. Mutat. Res., 5, 639-650... 

A systematic dependence of reaction order on temperature and pH is not visible, n varies between one and two. Different experimental conditions and/or missing details about these conditions as well as different analytical methods make a comparison of these results impossible. Staehelin and Hoigne (1985) proposed a possible explanation for the second order reaction (n = 2). Since in clean water ozone not only reacts with the hydroxide ions but also with the intermittently produced hydroxyl radicals (see Chapter A 2), it behaves like a promoter and the decay rate increases with the square of the liquid ozone concentration. This is supported by the results obtained by Gottschalk (1997). She found a second order decay rate in deionized water, compared to a first order decay rate in Berlin tap water, which contains about 4 mg L DOC and 4 mmol LT1 total inorganic carbon. Staehelin and Hoigne (1982) also found first order in complex systems. 

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