Color intensity

The color intensity of the complex is stable between pH levels of 3 and 9. 

Color intensity and permanence are improved by metal carboxylate salts, especially 2inc salts (83), which cataly2e the dye development and stabili2e the dye in its colored form. The substituted novolak resin, along with extender and binder, can be apphed to the receiving sheet as a solution or aqueous dispersion. Aqueous dispersions are probably the most widely used they are manufactured by the resin suppher or the user from the base resin. 

A procedure to measure both types of nitrogen oxide compounds at the same time involves development of a pink color by mixing FeSO with sulfuric acid, followed by measurement or comparison of color intensity. This general type of procedure and the possible alternatives ate discussed in References 148—150. 

PuUy hydroly2ed poly(vinyl alcohol) and iodine form a complex that exhibits a characteristic blue color similar to that formed by iodine and starch (171—173). The color of the complex can be enhanced by the addition of boric acid to the solution consisting of iodine and potassium iodide. This affords a good calorimetric method for the deterrnination of poly(vinyl alcohol). Color intensity of the complex is effected by molecular weight, degree of... 

Reactive groups have minimal auxochrome effect on color intensity, and color yield per molecular weight decreases with increasing numbers of reactive groups. Increased dye fixation and reduced environmental impact of hydrolyzed dye more than compensate for color reduction of additional reactive groups. 

In this work hybrid method is suggested to determine cationic surfactants in water. It is based on preconcentration of cationic surfactants in the some of ion associates with acidic dyes on the paper filter and measurement of color intensity by solid-phase specdophotomenic method or visual comparison. 

When the plate is inspected the color intensity of the chromatogram zones must be more intense at the top surface of the layer than it is when viewed from the back of the TLC/HPTLC plate. If this is not the case the reagent must be made less polar to avoid a frontal development across the thickness of the layer. 

The chromatogram is freed from mobile phase in a stream of warm air and immersed in the reagent solution for 1 s and then dried in a stream of cold air. Red to reddish-brown zones are formed on a colorless background. They often appear immediately but sometimes they only appear after some minutes their color intensity is completely developed after 30 min [1]. They can be employed for quantitative analysis. 

In situ qnantitatioa Quantitation by reflectance had to be performed as soon as possible, since the color intensity of a zone decreased ca. 40% within a day. Detection wavelength A = 34S nm detection limit 2.S ng per chromatogram zone (Fig.l). 

In general no warming is necessary to produce the colored zones pyridoxine is colored intense blue, pyridoxamine violet and pyridoxal dark blue [1, 3]. Phenols... 

Note The dipping solution can also be used as a spray solution. When using the spr solution it is possible to increase the color intensity by spraying afterwards with hy chloric acid (c = 2 mol/L) [16]. The blue chromatogram zones remain readily visibli for ca. 15 to 30 min then they begin to fade, while the background gradually acquirei a blue coloration [14]. 

The reactions that occur in a mixture of NO2 and N2 O4 lead to changes in concentrations. The concentration of NO2 can be determined experimentally, because NO2 is orange and N2 O4 is colorless. The color intensity of the gas mixture is proportional to the concentration of NO2. Figure 16-2 summarizes the results of quantitative experiments on the NO2 /N2 O4 system. The data show that the concentrations of both gases level off to constant values as the reaction reaches equilibrium. If the reaction to form N2 O4 went to completion, the concentration of NO2 would drop to zero. If the reaction to decompose N2 O4 went to completion, the concentration of N2 O4 would drop to zero. Instead, these reactions reach equilibrium when substantial amounts of both gases are present. 

The effects of catechin, epicatechin, procyanidin B2, caffeic acid, / -coumaric acid, myricetrin, and quercetrin on the color intensity and stability of malvidin 3-glucoside at a molar ratio of 1 1 under conditions similar to red wine were evaluated. " Flavan 3-ols appeared to have the lowest protective effects and flavonols the highest strong color changes were visually perceptible. " In the complexation of malvin chloride and natural polyphenols, flavonol glycosides by far exerted the best protector effect. ... 

According to EU purity criteria, color intensity is defined as the absorbance of a 0.1% (w/v) solution of caramel color solids in water in a 1 cm cell at 610 nm. The color intensity must be 0.01 to 0.12 for class I (E 150a), 0.05 to 0.13 for class II (E 150b), 0.08 to 0.36 for class III (E 150c), and 0.10 to 0.60 for class IV (E 150d). Ammonia caramels show the highest tinctorial power and are most commonly used as food colorants. Class I has the weakest coloring properties and is mostly used as flavor. 

Children Pain interviews may be conducted with children as young as 3 or 4 years of age however, communication may be limited by vocabulary.34 Terms familiar to children such as hurt, owie, or boo boo may be used to describe pain. The VAS is best used with children older than 7 years of age. Other scales based on numbers of objects (e.g., poker chips), increasing color intensity, or faces of pain may be helpful for children between 4 and 7 years of age. In children younger than 3 to 4 years of age, behavioral or physiologic measures, such as pulse or respiratory rate, may be more appropriate. Pain assessment in newborns and infants relies on behavioral observation for such clues as vocalizations (crying and fussing), facial expressions,... 

Thermochromism of spiroindolinonaphthooxazine is observed only in high-concentration solution.77 A high concentration ( 10 3 M) of 33 in ethanol produces a bluish solution, and its color intensity increases as the temperature of such concentrated solution increases. This thermal equilibrium is also affected by substituent groups. Donor substituent groups promote the formation of the colored form. 

Figure 2. Effect of Acid Concentration on Color Intensity...

Although Equation 10.17 is written in terms of concentration of a specific component, it can also be used if the identity of the solute is unknown. For example, adsorption is used to remove color from liquids. In such cases, the concentration of solute can be measured, for example, by a colorimeter and Equation 10.17 expressed in terms of arbitrary units of color intensity, providing the color scale varies linearly with the concentration of the solute responsible for the color. 

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