Conversion apparent

After monomer conversion, apparently further formation of copolymers may be effected by a mechanism of mechanosynthesis in the polymer-polymer system. 

This term was introduced to the normal chemical language in the 20th century due to the efforts of Bodenstein. In Semenov s view, the understanding that, no matter how complicated is a reaction s process the law of the elementary act is sufficiently simple, is exclusively the credit "of Van t Hoff s genius prediction, though he himself did not understand it quite clearly [5, p. 6]. Though the epithet "genius with respect to Jacob Henri Van t Hoff is still valid, the situation, however, defies its complete reconstruction. On the one hand, it is likely that Van t Hoff renounced in principle the analysis of complex reactions that do not obey the laws of "normal conversions . Apparently, it is for this reason that in the "Etudes he did not examine etherification reactions practically [19]. Van t Hoff studied such simple reactions as the decomposition of dibromosuccinic acid and the reaction of... 

Dopachrome conversion factor catalyzes the decolorization of dopachrome. The mechanism of this conversion apparently involves an isomeric rearrangement of a hydrogen atom from one position of the dopachrome molecule to another, an intramolecular oxidoreduction which results in a tautomeric shift forming 5,6-dihydroxyindole-2-... 

As a result of the kinetic analyses with both methods, the dependence of the activation energy on the conversion (apparent activation energy Ea) was calculated for all resins (PF, KLPF and modified KLPF). The experimental verification of the model suitability was done by comparing the calculated curves of conversion versus the predicted reaction times ta at 160°C with the curve of conversion versus time as directly measured by isothermal DSC data at 160°C. The reaction temperature of 160°C was used because it is well within the range of industrially relevant temperatures at which hot pressing is performed. 

Figure 10b diows the dye excitation and emisaon spectra recorded at various stages of conversion. Apparently the fluorescence is quenched more rapidly than the dye decomposes, vdiich indicates an energy transfer from the dye molecules to the conjugated polymer. 

Finally in Figure 6, model predictions are compared with Experimental GPC measurements on molecular weight distributions at 130°C. Simulation results and the corresponding experimental distributions are plotted at four different conversion levels. It must be noticed that the molecular weight distributions are scaled with respect to monomer conversion. Apparently, the calculated molecular weight distributions are in excellent agreement with the GPC measurements over the whole conversion range. 

Further improvements of the selective production of ethylene were obtained by Bodke et by co-feeding H2 to ethane-oxygen mixtures over a Pt-Sn coated monolith ethylene was produced at 80-85% selectivity with over 70% ethane conversion. Apparently the Pt-Sn alloy could favour the selective oxidation of hydrogen, which thermally drove the selective dehydrogenation of ethane to ethylene. 

When, in a column headed M.p., a value is given in parenthesis, it indicates that the compound is liquid at room temperature and that the value given is consequently the boiling-point. Conversely in a column headed B.p., values given in parenthesis are those of the melting-point. A blank space indicates that the compound has not apparently been recorded. 

Cyclohexane. The LPO of cyclohexane [110-82-7] suppUes much of the raw materials needed for nylon-6 and nylon-6,6 production. Cyclohexanol (A) and cyclohexanone (K) maybe produced selectively by using alow conversion process with multiple stages (228—232). The reasons for low conversion and multiple stages (an approach to plug-flow operation) are apparent from Eigure 2. Several catalysts have been reported. The selectivity to A as well as the overall process efficiency can be improved by using boric acid (2,232,233). K/A mixtures are usually oxidized by nitric acid in a second step to adipic acid (233) (see Cyclohexanol and cyclohexanone). 

The general reactivity of higher a-olefins is similar to that observed for the lower olefins. However, heavier a-olefins have low solubihty in polar solvents such as water consequentiy, in reaction systems requiting the addition of polar reagents, apparent reactivity and degree of conversion maybe adversely affected. Reactions of a-olefins typically involve the carbon—carbon double bond and can be grouped into two classes (/) electrophilic or free-radical additions and (2) substitution reactions. 

Reaction and Transport Interactions. The importance of the various design and operating variables largely depends on relative rates of reaction and transport of reactants to the reaction sites. If transport rates to and from reaction sites are substantially greater than the specific reaction rate at meso-scale reactant concentrations, the overall reaction rate is uncoupled from the transport rates and increasing reactor size has no effect on the apparent reaction rate, the macro-scale reaction rate. When these rates are comparable, they are coupled, that is they affect each other. In these situations, increasing reactor size alters mass- and heat-transport rates and changes the apparent reaction rate. Conversions are underestimated in small reactors and selectivity is affected. Selectivity does not exhibit such consistent impacts and any effects of size on selectivity must be deterrnined experimentally. 

The Piloty-Robinson pyrrole synthesis (74JOC2575,18JCS639) may be viewed as a monocyclic equivalent of the Fischer indole synthesis. The conversion of ketazines into pyrroles under strongly acidic conditions apparently proceeds through a [3,3] sigmatropic rearrange-... 

Treatment of 1-azirine (292) with eatalytie quantities of diehlorobis(benzonitrile)pal-ladium(II) gave a quantitative yield of the indole (293) (77CC664). This transformation proeeeds through the intermediaey of a 2 1 azirine-palladium ehloride eomplex. Conversion of the 1-azirine ring to indoles under uneatalyzed thermolytie eonditions provides a meehanistieally interesting eomparison with the Pd(II)-eatalyzed eonversions. The C—N bond eleavage in the latter is apparently aeeelerated as a result of the eoordination of the azirine to palladium. 

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