Normal Yellow

Fig. 1.7 Spectral change of the in vitro firefly bioluminescence by pH, with Photinus pyralis luciferase in glycylglycine buffer. The normally yellow-green luminescence (Amax 560 nm) is changed into red (Xmax 615 nm) in acidic medium, accompanied by a reduction in the quantum yield. From McElroy and Seliger, 1961, with permission from Elsevier.

The basicity of OLOA 1200 has been evidenced by its interaction with the oil-soluble acidic indicator dye, Brom Phenol Magenta E (EK 6810) which is normally yellow but turns blue and then magenta with increasing bacicity. The acidic form has an adsorption peak at 390 nm, the basic at 610 nm, and the isobestic point is at 460 nm. These spectra have be used to determine the concentration of OLOA 1200 in solution for adsorption isotherms. 

Neither o-NCB nor 2-EHA, individually, demonstrates exothermic activity at the normal Yellow 96 process temperatures. Morton s initial research and development for the Yellow 96 process identified the existence and described the two exothermic chemical reactions that can occur when the chemicals used to produce Yellow 96 are mixed and heated. The desired exothermic reaction to form Yellow 96 is initiated at an onset temperature of 38°C (100°F) and begins to proceed rapidly at a temperature of approximately 75°C (167°F). The undesired, exothermic reaction that results from the thermal decomposition of the Yellow 96 product is initiated at an onset temperature 195°C (383°F). 

The Collins/Sarett oxidation (chromium trioxide-pyridine complex), and Corey s PCC (pyridinium chlorochromate) and PDC (pyridinium dichromate) oxidations follow a similar pathway as the Jones oxidation. All these oxidants have a chromium (VI), normally yellow, which is reduced to Cr(IV), often green. 

Silver was one of several metals found to give a photochromic primary complex. In THF it was normally yellow (Ama = 470 nm). Activation at 450 nm, i.e. in the region containing the normal visible absorption band, generated a violet solution with in the 570-620 nm... 

Amber is fossilized tree resin that hardened over millions of years and now is valued as a gem. Baltic amber is thought to be hardened sap from pine trees. It is normally yellow-brown in color, but the shades vary from almost white to almost black. Although sometimes completely clear, amber often contains inclusions of insects or other matter, often considered desirable. Much amber is obtained along the shores of the Baltic Sea, but it is also found along the coasts of Sicily, Romania, and Myanmar. 

The heating of the solid salt again leads to melting and dissolution in the water of crystallisation hydrated Mg ions and H3O ions are formed just as in the aqueous solution (eqn. 2), so that the red coloration typical of methyl red at pH<6 is observed. In the crystal lattice the indicator does not change from its normal yellow color. 

High amylose (ca. 60-85% amylose) pea starch (HAP) was obtained from Stauderer (Germany) with a composition of starch 80% and protein ca. 1%. Normal yellow smooth pea starch (ca. 35% amylose STL) was purchased from Pelmolen (The Netherlands). The composition was starch 84% and protein ca. 5%. Water (W) and glycerol (G) were used as plasticizers. Waxy com (Amioca, WCN) and potato starch (Farina, PN) were obtained from National Starch and Avebe, respectively. 

Cuscuta. Since the end of the nineteenth century it was known that the normal yellow-orange coloration of the holoparasitic genus Cuscuta is due to a high content of carotenoids (Tamne 1883). About live decades later a considerable level of y-carotene, some a- and P-carotene as well as traces of lycopene and rubixanthin [(31 )-p, /-caroten-3-ol] could be detected in C. subinclusa Durand Hilg. and C. salina Engelm. (Mackinney 1935). C. australis was found to contain P- and y-carotene, a-carotene 5,6-epoxide, lutein, and taraxanthin (= lutein 5,6-epoxide) (Baccarini et al. 1965). 

During the reaction of ethyl 2-benzothiazolesulfonate with luciferase, the color of light emitted during the assay changed from the normal yellow-green to red. Experimental details have been presented elsewhere. ... 

The range of color of the azo family is normally yellow, orange and red with variations of each. Many of the violets and blue dyes have come out of production due to the greater heat and light stability of the violet and blue anthraquinone dyes. 

Previous reports suggested that bright yellow attracted whitefly more efficiently than dark yellow. Our own study also demonstrated that whitefly was attracted to a normal yellow and a greenish yellow most efficiently (/). 

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