Color changes cause

Nevertheless, delayed photochemical reactions after the end of the exposure are likely in both systems. For wood pulps, the outcome is strongly influenced by factors such as the increased lifetime and much retarded transport rate due to the trapping of intermediates and photoproducts in the solid matrices. Ibis has to be taken into account when designing experiments. The main color changes caused by light in mechanical pulps are fairly rapid, which enables accurate measurements to be made either directly after the irradiation or after a certain delay. Thermal reactions, e.g. hydrolysis and oxidation, which also occur in the pulps, can be prevented by keeping the pulps in a freezer before analysis. 

Applications directly dependent upon the color change caused by the molecular and electronic structures of the two species (A. B) and their corresponding absorption or emission spectra. 

Yu, L. (2002). Color changes caused by conformational polymorphism optical crystallography, single-crystal spectroscopy, and computational chemistry. J. Phys. Chem. A 106, 544-550. 

Color stability the resistance of a petroleum product to color change caused by hght, aging, etc. 

FIGURE 15.5 Typical example of color change caused by host-guest complexation pictures and corresponding UV-VIS spectra (a) A chloroform solution of Host 1 (1.85x10 M) at 25°C (solid line) (b) The same solution as (a) containing 2 equivalent of (/ )-j (dotted line). 

Similar spectral change can also be noticed when poor solvent is added to the system (solvatochromism). The color change caused by dissolving the polymer or removing the solvent from the polymer solution can also be referred to as the solvatochromism [38],... 

Features Maintains dye bath pH 8.5 minimizes color change caused by add hydrolysis eliminates harsh chems. used in neutralization and reduction clear of It. and med. shades... 

Features Minimizes color change caused by acid hydrolysis Properties SI. brn. to cl. liq. readily sol. in cold water pH 8.5-9.5 (5% aq.) Sunsolt PC-1 [Nicca USA]... 

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