Enhancer Decane

Evidence exists that the relative solubility of amines and inhibitors in heterogeneous oil-water systems could be decisive in formation of nitrosamines and blocking these reactions, Nitrosopyrrolidine formation in bacon predominates in the adipose tissue despite the fact that its precursor, proline, predominates in the lean tissue (5,6,7). Mottram and Patterson (8) partly attribute this phenomenon to the fact that the adipose tissue furnishes a medium in which nitrosation is favored, Massey, et al, (9) found that the presence of decane in a model heterogeneous system caused a 20-fold increase in rate of nitrosamine formation from lipophilic dihexylamine, but had no effect on nitrosation of hydrophilic pyrrolidine. Ascorbic acid in the presence of decane enhanced the synthesis of nitrosamines from lipophilic amines, but had no effect on nitrosation of pyrrolidine. The oil-soluble inhibitor ascorbyl palmitate had little influence on the formation of nitrosamines in the presence or absence of decane. 

Sazama, P., Capek, L., Drobna, H. et al. (2005) Enhancement of decane-SCR-N()x over Ag/alumina by hydrogen. Reaction kinetics and in situ FTIR and UV-vis study, J. Catal. 232, 302. 

Host-guest systems made from dendritic materials have potential in the areas of membrane transport and drug delivery [68, 84, 85]. In a recent report [136] Tomalia and coworkers investigated structural aspects of a series of PAM AM bolaamphiphiles (e.g., 50) with a hydrophobic diamino do decane core unit. Fluorescence emission of added dye (nile red) was significantly enhanced in an aqueous medium in the presence of 50 unlike the cases when 51 and 52 were added (Fig. 23). Addition of anion surfactants to this mixture generated supramolecular assemblies which enhanced their ability (ca.by 10-fold) to accommodate nile red (53). Further increase in emission was noted by decreasing the pH from the normal value of 11 for PAMAM dendrimers to 7. At lower pH values the... 

Further improvement of the synthetic performance of the reaction system was attempted by adapting the composition of the organic phase in such a way that partition of products into the organic phase was enhanced. In the synthesis of (R) -3,3 -furoin, product extraction was increased by 11% when hexane was mixed with 2-octanone in a ratio of 3 1, while replacing hexane with pure 2-octanone, 2-pentanone, 2-butanone, heptane, or decane yielded considerably lower product concentrations. No apparent rule was underlying these results. 

Another health hazard associated with exposure to UV radiation is the potential cocarcinogenic activity of UV light with the contaminant on the skin. Past studies have found that exposure to UV radiation results in a significant enhancement of the effects of chemical carcinogens such as 7,12-dimethyl benzanthracene (13) and benzo[a]pyrene (14). Even normally innocuous compounds such as anthracene, n-decane and n-tetradecane can develop tumorigenic activity in mice under irradiation with long-wavelength (>350 nm)... 

The platforming catalyst was the first example of a reforming catalyst having two functions.43 44 93 100-103 The functions of this bifunctional catalyst consist of platinum-catalyzed reactions (dehydrogenation of cycloalkanes to aromatics, hydrogenation of olefins, and dehydrocyclization) and acid-catalyzed reactions (isomerization of alkanes and cycloalkanes). Hyrocracking is usually an undesirable reaction since it produces gaseous products. However, it may contribute to octane enhancement. n-Decane, for example, can hydrocrack to C3 and C7 hydrocarbons the latter is further transformed to aromatics. 

This beneficial effect was attributed to rate enhancements of reduction processes. With benzoic acid, total degradation of the ring to CO2 occurred and the detection of salycilic acid suggested the intervention of 0H° radicals (56). These radicals were also proposed to explain the oxidation of n-Cx alkanes (x = 6,7,9,10) and of cyclohexane in 1 1 vol. water ydrocarbon two-phase mixtures over 10 wt °l Pt/Ti02 Traces of alcohols (and of 2-, 4-, 5-decanone with decane) were detected. No transformation occurred without O2 and in the absence of H2O the rate was substantially decreased. The role of Pt was attributed to a greater ease of oxygen reduction however the oxidation rate was only decreased by a factor of about 1.5 without Pt (59). 

Unfortunately, even using this optimized procedure, we were not able to improve the conversion of primary alcohols into the corresponding aldehydes. However, close examination of the oxidation behavior of several primary aliphatic alcohols revealed intriguing features (Table VII). Whilst poor conversion of 1-decanol 23 to decanal 24 was achieved (Table VII, Entry 1), dibenzyl leucinol 25 and Boc-prolinol 27 were quantitatively transformed into the corresponding aldehydes (Table VII, Entries 2 and 3). The enhanced reactivity of 25 and 27 could be due either to an increased steric effect at the a-carbon center, to an electronic influence of the a-nitrogen substituent or to a combination of both. To test the importance of steric hindrance, the aerobic oxidation of cyclohexane methanol 29 and adamantane methanol 31 was carried out. Much to our surprise, oxidation of 29 afforded 30 in 70% conversion (Table VII, Entry 4) and transformation of 31 to 32 proceeded with 80% conversion (Table VII, Entry 5). Clearly increased substitution at the a-position favors the oxidation of primary aliphatic alcohols, although the conversions are still not optimum. 

Figure 5.44 (a) General molecular structure of the porphyrin disulfides, PDSn, described by Ishida and Majima [76]. (b) Changes in the surface plasmon enhanced fluorescence spectra for the exchange reaction of a decane thiol SAM with a 50 mmol dm-31,2-dichloroethane solution of PDS10 (Xem = 725 nm Xex = 425 nm). From A. Ishida and T. Majima, /. Chem. Soc., Chem. Commun., 1299-1300 (1999). Reproduced by permission of The Royal Society of Chemistry... 

The photophysical properties of the self-assembled dimer [54]2 have been studied in detail with various spectroscopic and computational methods [53,54], In the lowest excited singlet (Si) state, the excitation delocalizes over the two macrocycles, and the non-radiative decay is enhanced by dimerization. By contrast, the exciton interaction is very weak in the lowest excited triplet (Ti) state. In the excited-state absorption spectrum recorded in 1-decane, two sharp bands at 658 and 694 nm are observed, which can be attributed to the Q bands of the Tx self-assembled phthalocyanine dimer. 

A synergistic effect was observed for the hydroisomerization of n-decane with intimately mixed Pt/ZSM-22 and deep-bed steamed zeolite NH4Y (311). The synergism is rationalized in terms of a two-step isomerization mechanism. Pt/ZSM-22 converts decane selectively into 2-methylnonane, even at high conversion. The Y sieve receives this 2-methylnonane as its feed inside this Pt-free sieve a high concentration of monobranched alkenes will build up. This enhances their subsequent conversion to multibranched alkenes. 

Previously, Durst and Stephan Q) observed some enhancement in heat transfer coefficients in natural convection in mixtures of n-heptane -- methane as the two-phase region was entered. We reported heat transfer results earlier ( ) for free convection and cross flow about a heated horizontal cylinder in a supercritical n-decane--C02 mixture. These also showed enhancement in the two-phase region relative to single phase. At that time, analysis was hindered by the unavailability of estimates or measurements of some crucial mixture properties. Happily, this situation has been remedied somewhat and we can now draw some conclusions. 

The most striking feature of these results is the steep rise in the heat transfer coefficient for the n-decane--CO2 results at x -0.973 at both pressures. This rise coincided in both cases with the onset of the condensation process as we observed droplets or streamers falling from the test section. In all but the n-decane-CO2 mixture of x - 0.867 we saw some form of dense material falling from the test section, but it was not always clear whether this was an immiscible phase the appearance was often more like that of density schlieren. We offer no explanation for the fact that, in the n-pentane--C09 results, the liquid side heat transfer coefficients are greater than for the vapor side in contrast to the n-decane--CO2 system, but we stress that the vapor side condensation results for the former are still "enhanced in the sense described below. 

The results for the TEA--water mixtures at atmospheric pressure are shown in Figure 6. These are for TEA mole fractions of x 0.05 and 0.59. The LOST is 18.2 at x - 0.09. We also obtained a very similar data set at the latter mole fraction, but we omitted it for clarity. For contrast and comparison, a data set for pure water is shown. These mixture results again show a sharp rise in heat transfer coefficient as condensate first appeared. In fact, the appearance was remarkably similar to the n-decane--C02 results for x - 0.973 discussed above, but the visibility of the phase separation was enhanced by the presence of a fine emulsion at the phase interface and the absence of strong refractive index gradients characteristic of the supercritical systems. This permitted the structure of the interface to be seen more clearly. In Figure 7 we show photographs that typify the appearance of the two phases. In all cases observed here, both in supercritical vapor--liquid and in liquid--liquid systems, the dense phase appears to wet the cylinder surface regardless of composition. 

Polar solvents are known to enhance the acylation reaction over conventional catalysts. Accordingly, sulfolane, a higher polar solvent, enhances appreciably the activity of Y(12) using BC as acylating agent (no solvent 36%, decane 20%, and sulfolane 94% conversion, respectively). 

Beilstein Handbook Reference) Amidex CP N.N-Bis(2-hydroxyethyl)decan-1-amide BRN 1785093 Capramide DEA Capric acid diethanolamide Deoanamide, N,N-bis(2-hydroxy-ethyl)- EINECS 205-234-9 Standamid CD Upamide CD, Capramide DEA (2 1) - diethanolamine detergent, foam enhancer for anionic systems solubilizes fragrances into hydroalcoholic systems ... 

The presence of the polar groups introduces another factor capable to enhance the aggregation numbers for the zwitterionic samples in n-decane. Much lower Nw values were observed for the amine-capped copolymers, meaning that the amine groups are not polar enough to enhance the association process. Typical LALLS plots are given in figure 12. 

Intermediate products (e.g. fatty acids) can have a toxic effect (Fend, 1961). As a provisional explanation, we assume that the dissociated forms of the fatty acids no longer guarantee the passage of anions. The enhancement of assimilation by dialysis culture and specific growth inhibition by its dialyzable material, as noticed in a kerosene medium, were demonstrated also in the case of individual n-alkane, i.e. hexadecane or decane. These findings seem to indicate that the effect of dialysis culture on alkane assimilation is a fairly general phenomenon. From the evidence presented for the growth inhibition by the dialysable substance, it is likely that the improvement of hydrocarbon... 

For intermediate reaction rates the use of the enhancement factor is not consistent with the standard approach of diffusional limitations in reactor design and may be somewhat confusing. Furthermore, there are cases where there simply is no purely physical mass transfer process to refer to. For example, the chlorination of decane, which is dealt with in the coming Sec. 6.3.f on complex reactions or the oxidation of o-xylene in the liquid phase. Since those processes do not involve a diluent there is no corresponding mass transfer process to be referred to. This contrasts with gas-absorption processes like COj-absorption in aqueous alkaline solutions for which a comparison with C02-absorption in water is possible. The utilization factor approach for pseudo-first-order reactions leads to = tfikC i and, for these cases, refers to known concentrations C., and C . For very fast reactions, however, the utilization factor approach is less convenient, since the reaction rate coefficient frequently is not accurately known. The enhancement factor is based on the readily determined and in this case there is no problem with the driving force, since Cm = 0- Note also that both factors and Fji are closely related. Indeed, from Eqs. 6.3.C-5 and 6.3.C-10 for instantaneous reactions ... 

The yield of CDs could be enhanced by adding appropriate organic solvent in the system. Chen et al. reported that the yield of CDs increased about 100% when adding 10% of ethanol [20]. Several water-insoluble organic solvents such as decane and toluene can also be used to increase the yield of CDs as described in Sec. 3.1.1.2. However, those solvents are prohibited for CD production when CDs are used in food because of the toxicity. 

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