Coloration and decoloration

Although photochemical reactions in general take place very rapidly, for application to switching devices it is essential to know the response times. The photoinduced coloration and decoloration rates of diarylethenes have been measured by using... 

Use (As salts) Coloring and decolorizing glass, in temperature-compensating capacitors for radio, television, and radar. In carbon-arc cores (fluoride), in stainless steel (oxide), metallurgical research, textile treatment. 

In one study (Davis, 1986), subcutaneous injections of A. barbadensis inhibited mustard-induced rat paw edema compared to control (p < 0.01). The effectiveness increased with the use of RNA and vitamin C (p < 0.001). Another study (Vazquez et al., 1996) showed that intraperitoneally administered aloe vera extracts decreased carrageenan-induced rat paw edema and peritoneal neutrophil infiltration in response to carrageenan. It was also shown that aloe vera decreased prostaglandin E2 production. Mice receiving subcutaneous injections with colorized aloe vera gel containing anthraquinones at doses of 1, 10, and 100 mg/kg for 7 d had no reduction in their wound diameter (Davis et al., 1987). However, those receiving the same doses of decolorized (i.e., without anthraquinones) aloe vera had a decrease in wound diameter. Rats injected with colorized aloe vera for 12 d also had a decrease in wound diameter. These same authors also noted that polymorphonuclear leukocyte (PMN) infiltration and inflammation are decreased by both colorized and decolorized aloe vera. 

Photochromic performance was enhanced when the naphthopyran moiety was located in the middle rather than at the terminus. A middle disposition of the naphthopyran provides better encapsulation by the polymeric arms giving improved coloration and decoloration rates and higher optical density in the colored open-state [26]. 

Figure 43.28. Transient current versus time response for an all-solid state device, using tungsten oxide and nickel oxide as electrochromic layers and zirconium oxide as an ion conductor. The transient current is shown for both the coloration and decoloration process.

Takagi et al. reported the intercalation of l, 3, 3 -trimethylspiro[2//-l-benzopyran-2,2 -indoline] (H-SP) and its 6-nitto (NO2-SP) and 6-nitro-8-(pyri-dinium)-methyl (Py+-SP) derivatives into montmorillonite their photochromic behavior (the photochromic reaction of spiropyran is shown in Fig. 22) has been studied for colloidal systems (208). The effects of intCTcalation on the rate of thermal coloration and decoloration have been compared with those in other systems, such as colloidal silica, hexadecyltrimethylammonium bromide, and sodium dodecylsulfate (SDS) micelles. 

Following the separation, proteins are generally visualized by staining the gel with one of a range of stains (typically silver or Coomassie blue). It has been demonstrated that staining the gel using silver or Coomassie blue can result in loss of most metals from their bound proteins. To avoid the loss of metals from protein bands and the contamination of sample resulting from the use of colorant and decolorant, two electrophoresis gel must be loaded with the same sample and run simultaneously, the first is used for XRF analysis and the second is colored and used for protein quantification. The inability to stain the gel before SRXRF measurement requires the use of scan mode for XRF... 

Plos, G. Guerin, F. Process for fast coloring and decoloring human keratinic fibers with direct dyes. Fr. Demande FR 2845906,2004 Chem. Abstr. 2004, 140, 326616. 

---