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Saccharin concentrations

When diazomethane is slowly added to excess lactam, the anions formed can interact with unreacted lactam by means of hydrogen bonds to form ion pairs similar to those formed by acetic acid-tri-ethylamine mixtures in nonpolar solvents. The methyldiazonium ion is then involved in an ion association wdth the mono-anion of a dimeric lactam which is naturally less reactive than a free lactam anion. The velocity of the Sn2 reaction, Eq. (7), is thus decreased. However, the decomposition velocity of the methyldiazonium ion, Eq. (6a), is constant and, hence, the S l character of the reaction is increased which favors 0-methylation. It is possible that this effect is also involved in kinetic dependence investigations have shown that with higher saccharin concentrations more 0-methylsaccharin is formed. [Pg.267]

A study using a model reaction system consisting of cumene hydroperoxide (CHP), A,A-dimethyl-/)-toluidine (DMPT), and o-benzoic sulfimide (saccharin) in toluene (without reactive acrylic monomer) showed conclusively that the DMPT was depleted significantly during the initiation step of an anaerobic reaction. The saccharin concentration was unchanged during this process. The initiating species may be radical anions derived from DMPT rather than reactive free radicals derived from the CHP [17]. [Pg.753]

The beneficial additive effect on stress evolution during electrodeposition is shown in Fig. 16. In (A), from in situ measurements, one can see that for Permalloy films of 100 nm thickness, the significant stress reduction in deposit is achieved if saccharin (stress reduction 50%) or 1-Methionine (stress reduction 85%) is used as additives in plating solution. The effect of saccharine concentration on stress in electrode-posited CoNiFe films is shown in Fig. 16(B). These data suggest that stress reduction is decreasing towards asymptotic value for increasing saccharin content in the solution. [Pg.330]

Figure 3. Saccharin concentrations from. 03 to 1.0% were each paired with all other concentrations in 2-bottle, 24-hr tests. The percent of the pairings in which each of the concentrations was preferred is plotted. Figure 3. Saccharin concentrations from. 03 to 1.0% were each paired with all other concentrations in 2-bottle, 24-hr tests. The percent of the pairings in which each of the concentrations was preferred is plotted.
Saccharin (imide of o-sulphobenzoic acid). Upon oxidising o toluene-sulphonamide with potassium permanganate in alkaline solution, the sodium salt of o-sulphonamidobenzoic acid is formed, which upon acidifying with concentrated hydrochloric acid or warming passes spontaneously into the cyclic imide of o-sulphobenzoic acid or saccharin ... [Pg.821]

The concentrations of benzoic acid, aspartame, caffeine, and saccharin in a variety of beverages are determined in this experiment. A Gig column and a mobile phase of 80% v/v acetic acid (pH = 4.2) and 20% v/v methanol are used to effect the separation. A UV detector set to 254 nm is used to measure the eluent s absorbance. The ability to adjust retention times by changing the mobile phase s pH is also explored. [Pg.612]

Acesulfame-K is a white crystalline powder having a long (six years or more) shelf life. It readily dissolves in water (270 g/L at 20°C). Like saccharin, acesulfame-K is stable to heat over a wide range of pH. At higher concentrations, there is a detectable bitter and metallic off-taste similar to saccharin. Use of the sodium salt of feruHc acid [437-98-4] (FEMA no. 3812) to reduce the bitter aftertaste of acesulfame-K has been described (64). The sweetness potency of acesulfame-K (100 to 200x, depending on the matching sucrose concentration) (63) is considered to be about half that of saccharin, which is about the same as that of aspartame. [Pg.276]

Saccharin imparts a sweetness that is pleasant at the onset but is followed by a lingering, bitter aftertaste. Sensitivity to this bitterness varies from person to person. At high concentration, however, most people can detect the rather unpleasant aftertaste. Saccharin is synergistic with other sweeteners of different chemical classes. For example, saccharin—cyclamate, saccharin—aspartame, saccharin—sucralose, and saccharin—aUtame combinations all exert synergy to various degrees. The blends, as a rule, exhibit less aftertaste than each of the component sweeteners by themselves. [Pg.277]

The mechanism of this variant of the Gabriel-Colman reaction has been investigated. Treatment of saccharine derivatives 45-48 with 1-2 equivalents of sodium alkoxide at room temperature provides esters 49-52 in good yields treatment of 45-48 with sodium alkoxide at reflux provides the expected benzothiazines 53-56. Increased concentration leads to higher yields. [Pg.421]

For example, if saccharin (33) is methylated in benzene suspension, then only iV-methylsaccharin is isolated. If an ethereal saccharin solution is added to a concentrated solution of diazomethane in excess, then 10% of 0-methylsaecharin (34) can be detected in addition to the A"-raethy] derivative. Finally, if the diazomethane solution is gradually added to a saturated ethereal solution of saccharin, the proportion of 0-methylation increases to 24%. " ... [Pg.266]

For high diazomethane concentrations, the Sn2 reaction, Eq. (7), and thus A—methylation occurs, whereas 0-methylation is favored by lower diazomethane concentrations, Eq, (6) (for an interpretation of this effect, according to Arndt, see references 33 and 42). The extent of this effect is limited by the constitution of the lactam in question. The fact that the addition of the sodium salt of saccharin to the reaction mixture leads to increased A -mcthylation for saccharin can be taken as supporting the foregoing interpretation. [Pg.267]

In the formation of C6 acids (namely, organic acids containing 6 or fewer carbon atoms), at OH concentrations greater than 10 mM, route 5 occurs preferentially to route 6, and lactic acid and saccharinic acids predominate in the product,... [Pg.454]

The binding specificity of d-[ C]glucose by the taste-papillae membranes, compared to that of control membranes isolated from epithelial tissue, has been confirmed in two studies. One inherent problem in the approach is that the stimuli, primarily carbohydrate sweeteners, are not ideal model compounds to use, as they are not active at low concentrations and do not show sufficiently high binding-constants. The use of other stimulus compounds that are at least several hundred times sweeter than sucrose, such as saccharin, dihydrochalcone sweeteners, dipeptide sweeteners, stevioside, perillartine and other sweet oximes, the 2-substituted 5-nitroanilines, and... [Pg.330]

Thus, the increase in concentration needed to match the effect of a 10-fold increase in sucrose concentration is 0.154/2.44 x 10 = 630-fold. Crosby and coworkers suggested that this is close to the situation that occurs with saccharin, and it is doubtless responsible for the differences in perceived sweetness intensity (200-700 times that of sucrose) for sensory determinations conducted at different concentrations. [Pg.351]

The artificial sweeteners erythritol, sodium saccharin, and aspartame (Fig. 25) were also studied. Figure 26 shows potential oscillation in the presence of these artificial sweeteners [22]. The oscillation modes of these substances differed considerably. For erythritol above 10 mM, Fa.sds slightly shifted to more negative potentials. and Fb.sds were essentially unaffected by this sweetener. Erythritol thus induces change in the oscillation mode in much the same way as sugars. At 1 mM-1 M sodium saccharin, E and Fa.sds shifted to more negative values with increase in its concentration. For aspartame at less than 10 mM, there was no change in potential. [Pg.719]

During the discussions of a potential carcinogenicity of saccharin, contaminants, especially o-toluene sulphonamide, were blamed for the toxicological effects observed in these studies. The studies carried out on such contaminants which in former times occurred in concentrations well exceeding 1000 ppm, did, however, not reveal any such effects, and the observed effects today are believed to be saccharin-specific. In order to minimise risks for consumers, low maximum levels for these products were introduced into the specifications. [Pg.239]

The sweetening agent saccharin is also derived from a sulphonamide it is prepared from toluene-o-sulphonamide by oxidising the CHs-group to carboxyl with permanganate ring closure is subsequently brought about by the action of concentrated hydrochloric acid ... [Pg.200]

Expressed as concentration of saccharin in diets of test animals (per cent of diet). Number of animals diagnosed with bladder tumors after a lifetime of exposure, with exposures beginning in utero. [Pg.190]

Andersen et a/.," with a saccharine-particle method, found a weak positive association between tracheobronchial clearance and nasal clearance. A strong positive correlation would have indicated that information about the tracheobronchial clearance rate can be derived by studying clearance rates in the nose, which is more accessible. The saccharine method was shown to be a useful clinical tool for evaluating the status of the nasal mucociliary function in human subjects exposed to ambient pollutants or to controlled concentrations of specific pollutant gases or aerosols. [Pg.297]


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See also in sourсe #XX -- [ Pg.54 ]




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