Methylammonium bromide

Acids such as sulfuric or nitric acids or bases such as sodium hydroxide may catalyze the hydrolysis of PET. It has been demonstrated that the rate of alkaline PET hydrolysis increases in the presence of quaternary ammonium compounds.26 27 Niu et al.26 reported an increase in the rate of alkaline PET degradation in the presence of dodecylbenzyldimethylammonium chloride at 80°C. Polk et al.27 reported increases in the rate of sodium hydroxide depolymerization of PET in the presence of trioctylmethylammonium chloride, trioctyl-methylammonium bromide, and hexadecyltrimethylammonium bromide at 80° C. 

In activated sludge, 80.6% degraded after a 47-h time period (Pal et al., 1980). Chemical/Physical. Zhang and Rusling (1993) evaluated the bicontinuous microemulsion of surfactant/oil/water as a medium for the dechlorination of polychlorinated biphenyls by electrochemical catalytic reduction. The microemulsion (20 mL) contained didodecyldi-methylammonium bromide, dodecane, and water at 21, 57, and 22 wt %, respectively. The catalyst used was zinc phthalocyanine (2.5 nM). When PCB-1221 (72 mg), the emulsion and catalyst were subjected to a current of mA/cm on 11.2 cm lead electrode for 10 h, a dechlorination yield of 99% was achieved. Reaction products included a monochlorobiphenyl (0.9 mg), biphenyl, and reduced alkylbenzene derivatives. 

Detergents (26, 41, 46, 96, 97) Optimal concentrations of deoxycholate, cholate, Triton X-100, and cetyltri-methylammonium bromide activate, as does urea. Activation of phosphotransferase > that of phosphohydrolase. Supraoptimal levels inhibit, as do all tested concentrations of sodium lauryl sulfate and Tweens 20 and 80. (See also Lysolecithin, Fatty acids, and Long-chain fatty acyl-CoA esters, above)... 

Dihydropyridine 129 has been shown to catalyze Michael reactions in aqueous cationic micelles of cetyltri-methylammonium bromide (Scheme 34) <2003CL1064>. In the micelles, dihydropyridine 129 ionizes to form an acetophenone enolate salt 130. The highly basic enolate deprotonates the Michael donor which then rapidly reacts with the Michael acceptor. The use of anionic surfactants did not promote Michael reactions, suggesting that the cationic micelles promote the dissociation of salt 130. 

Figure 1 Variation of CQ and r/Q as a function of alkyl chain length (n) in n-alkyltri-methylammonium bromides (CnH2n+i(CH3)3N+Br ).16...

A. J. Ivanov, V. M. Vagabov, V. M. Fomchenkov and I. S. Kulaev (1996). Study of the influence of polyphosphates of cell envelope on the sensitivity of yeast Saccharomyces carlsbergensis to the cytyl-3-methylammonium bromide. Microbiologiia, 65, 611-616. 

Consists chiefly of tetradecyltrimethylammonium bromide together with smaller amounts of dodecyl- and hexadecyltri-methylammonium bromides. 

SYNS a-CYCLOPENTYL-2-THIOPHENEGLYCOLATE DIETHYL(2-HYDROXYETHYL)METHYLAMMONIUM BROMIDE 2-DIETHYLAMINOETHYL-2-CYCLOPENT-YL-2-(2-THIENYL)HYDROXYACETATEMETHOBROM-IDE 2-DIETHYLAMINOETHYL-a-CYCLOPENTYL-2-THIOPHENEGLYCOLATE METHOBROMIDE MONODRAL MONODRAL BROMIDE WIN 4369... 

Capillary electrophoresis Capillary electrophoresis (CE) is used to analyze sodium, potassium, calcium, and magnesium in water samples. The detection is conducted by reverse absorbance measurements. Sufficient separation of the four cations is established with an electrolyte solution of 5 mM imidazole/6.5 mM a-hydroxyisobutyric acid/2 mM 18-crown-6 ether of pEI 4.1 [42]. CE with a contactless conductometric detector is used to determine small anions and cations in water samples from different sources. 2-(N-Morpholino)ethanesulfonic acid/histidine-based (Mes/Elis) electrolytes are used for direct conductivity detection of anions and cations, while ammonium acetate is used for indirect conductivity determination of alkylammonium salts. Eor the simultaneous separation procedure, involving dual-opposite end injection, an electrolyte consisting of 20 mM Mes/EIis, 1.5 mM 18-crown-6 and 20 mM cetyltri-methylammonium bromide provides baseline separation of 13 anions and cations in less than 6 min [43]. Also CE with a capacitively coupled... 

Cationic surfactants, where the hydrophilic group carries a positive charge (e.g., quaternary ammonium halides, R4N" C1 ). Examples of pharmaceutical importance include cetrimide, a mixture consisting mainly of tetradecyl (ca. 68%), dodecyl (ca. 22%), and hexadecyltri-methylammonium bromides (ca. 7%), as well as benzalkonium chloride, a mixture of alkyl-benzyldimethylammonium chlorides of the general formula [C6H5CH2N+(CH3)2R]C1, where R represents a mixture of the alkyls from... 

A more complete extraction " of polysaccharides was attempted by refluxing the soil for two 30-minute periods with 98 % formic acid containing lithium bromide. The organic matter extracted was precipitated by the addition of isopropyl ether and was redispersed in lithium chloride solution. The colored humic substances were then precipitated with hexadecyltri-methylammonium bromide, while the acidic and neutral polysaccharides were kept in solution by the lithium chloride. The possible degradative effects of hot formic acid on soil polysaccharides have not yet been investigated. 

Benzalkonium chloride benzethonium chloride dodecyltri-methylammonium bromide hexadecyltrimethylammonium bromide trimethyltetradecylammonium bromide. 

Lewis acid catalysis in micellar systems [33] was first found in the model reaction in Table 14-6 [34]. While the reaction proceeded sluggishly in the presence of 0.2 eq. Yb(OTf)3 in water, remarkable enhancement of the reactivity was observed when the reaction was carried out in the presence of 0.2 eq. Yb(OTf)3 in an aqueous solution of sodium dodecyl sulfate (SDS, 0.2 eq., 35 mM), and the corresponding aldol adduct was obtained in 50% yield. In the absence of the Lewis acid and the surfactant (water-promoted conditions), only 20% yield of the aldol adduct was isolated after 48 h, while 33% yield of the aldol adduct was obtained after 48 h in the absence of the Lewis acid in an aqueous solution of SDS. The amount of the surfactant also influenced the reactivity, and the yield was improved when Sc(OTf)3 was used as a Lewis acid catalyst. Judging from the critical micelle concentration, micelles would be formed in these reactions, and it is noteworthy that the Lewis acid-catalyzed reactions proceeded smoothly in micellar systems [35]. It was also found that the surfactants influenced the yield, and that Triton X-100 was effective in the aldol reaction (but required long reaction time), while only a trace amount of the adduct was detected when using cetyltri-methylammonium bromide (CTAB) as a surfactant. 

Mathematical Treatment of the Emulsification of Benzene and Styrene in Aqueous Hexadecyltri-methylammonium Bromide-Cetyl Alcohol Mixtures... 

A mechanism which is consistent with the experimental observations for the production of the chlorohydrin ester is given in Fig. 6. The first stage of the reaction involves ionisation of 2-ethylhexanoic acid by the catalyst cetyltri-methylammonium bromide. Subsequent attack of the carboxyanion... 

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