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Luminous yield

A very important application of the heats of reaction is the calcn of the reaction temp of propints which determine in part the ballistic performance. Heats of reaction also permit the calcn of the adiabatic reaction temp of pyrot reactions which are of value in judging the luminous yield of flares as well as the heat output of thermite reactions... [Pg.685]

The thickness of the organic layer or, in multilayer devices, of the organic layers, is as a rule in the range between 10 and a few 100 nanometers. The electrooptics of organic devices is thus also a nanotechnology. The optimisation of the contacts and the layer thicknesses is - along with the intrinsic materials parameters - of central importance for the efficiency of the devices, i.e. for the luminous yield of electroluminescent devices or for the electric power of photovoltaic cells. The devices must therefore be optimised by both controlled variation of the layers and layer thicknesses and by comparison with simulations. [Pg.366]

Assemble the apparatus shown in Fig. 1 V, 67, 1 this is self-explanatory. The distilling flask has a capacity of 250 ml. and the beaker contains 150 ml. of 10 per cent, sodium hydroxide solution. All corks must fit well and should be coated with paraflSn wax (by dipping into molten wax, and allowing to drain). Place half of the yield of the dry phenyldiazonium fluoborate in the distilling flask. Heat the solid gently with a small luminous flame at one point near its surface until decomposition begins withdraw the flame and allow the reaction to continue... [Pg.610]

Place 25 g. of methyl methacrylate polymer (G.B. Diakon (powder). Perspex (sheet) U.S.A. Lucite, Plexiglass) in a 100 ml. Claisen flask, attach an efficient condenser e.g., of the double smface type) and distil with a small luminous flame move the flame to and fro around the sides of the flask. At about 300° the polymer softens and undergoes rapid depolymerisation to the monomer, methyl methacrylate, which distils over into the receiver. Continue the distillation until only a small black residue (3-4 g.) remains. Redistil the hquid it passes over at 100-110°, mainly at 100-102°. The yield of methyl methacrylate (monomer) is 20 g. If the monomer is to be kept for any period, add 0 -1 g. of hydro quinone to act as a stabiUser or inhibitor of polymerisation. [Pg.1023]

Heat stability The Oplophorus luminescence system is more thermostable than several other known bioluminescence systems the most stable system presently known is that of Periphylla (Section 4.5). The luminescence of the Oplophorus system is optimum at about 40°C in reference to light intensity (Fig. 3.3.3 Shimomura et al., 1978). The quantum yield of coelenterazine is nearly constant from 0°C to 20°C, decreasing slightly while the temperature is increased up to 50°C (Fig. 3.3.3) at temperatures above 50°C, the inactivation of luciferase becomes too rapid to obtain reliable data of quantum yield. In contrast, in the bioluminescence systems of Cypridina, Latia, Chaetopterus, luminous bacteria and aequorin, the relative quantum yields decrease steeply when the temperature is raised, and become almost zero at a temperature near 40-50°C (Shimomura et al., 1978). [Pg.84]

The tissue distribution of P-glycoprotein yields important clues to its function. In most tissues it is localized to the apical (luminal) membrane of polarized epithelial cell layers. This location suggests that P-glycoprotein extrudes its substrates from the epithelial cells into the adjacent lumen. It is anticipated that P-glycopro-tein plays an important role as a protective mechanism against naturally occur-... [Pg.161]


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See also in sourсe #XX -- [ Pg.448 ]




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