Purple short

Phenyl methyl selenium di-iodide, (C6H5)(CH3)SeI2, occurs when the corresponding dibromide is triturated at 40° C. with a concentrated solution of potassium iodide. It crystallises from alcohol in glistening, purple, short prisms, M.pt. 69° to 71° C. 

From the colorless state it can be switched with light of short wavelength (A = 380 nm) via an electrocycHc ring opening and cis/trans rotation of one half of the molecule into a state with violet/purple color. The reverse reaction is effected by visible light (A = 580 nm). Since the system is metastable, one of the two reaction directions is matched by a rival thermal reaction, the thermoreversion. This progresses, however, in the case of benzospiropyran, at room temperature by a factor of 10 slower than the light-induced reaction. 

Initially the reaction may take on various colors, red, purple, etc., but after a short time a dull gray-brown color appears, which is gradually replaced by a yellow-brown or olive-drab color. 

NiFe] hydrogenase of the purple-sulfur bacterium A. vinosum can exist in various redox states (see Fig. 7.5). Until recently the redox transitions have been studied under equilibrium conditions only. I will shortly report here on the first rapid reactions of H2 and CO with [NiFe] hydrogenases using the so-called rapid-mixing rapid-freezing technique. This technique enables the study of the reaction of an enzyme with its substrate and/or an inhibitor on a timescale down to 10 ms (milliseconds). The basic elements of... 

They produce distinctive colored flames when burned lithium = crimson sodium = yellow potassium = violet rubidium = purple cesium = blue and the color of francium s flame is not known. Many of francium s characteristics have not been determined owing to the fact that it is rare and all of its many radioactive isotopes have short half-lives. 

Sodium bicarbonate- and borax bicarbonate-based dry chemicals were among the first dry agents used in portable fire extinguishers. About 1960, the sodium bicarbonate dry chemical was modified to make it compatible with protein-based, low-expansion foam to create a dual agent extinguishing system. Shortly thereafter, the more effective Purple K based extinguishers replaced sodium bicarbonate extinguishers. 

The properties of this compound have been discussed previously.6 The complex is a purple-black solid readily soluble in organic solvents. The solid is stable in air for short periods of time but indefinitely under nitrogen. It melts at 146.5-147.0° with some decomposition and its 1R spectrum in CH2C12 exhibits t jo at 1667 (s) and 1512 (m) cm 1. 

Di-/i-chloro(dichloro)bis[77 -T7 -2,7-dimethylocta-2,6-diene-l,8-diyl)diruthenium (compound A) is a purple crystalline compound, that is indefinitely stable at room temperature under a nitrogen atmosphere. For short periods it can also be handled in air. MS (El) m/z 616 (M + ). In the solid state the product shows symmetry Ci, ° but it exists as a mixture of two diastereomers in solution. It reacts with various Lewis bases L to form the monomers Ru(t7 77 -CioHi6)Cl2L and it shows catalytic activity in ROMP polymerization. ... 

Salvia divinorum Epling Jdtiva-M. is one of the vision-inducing plants used by the Mazatec Indians of central Mexico. The present status of research is summarized. Experiments with material collected at different Oaxacan sites confirmed that the mint has white (rather than blue) flowers with a purple calyx and that flowering is induced by short daylength. 

A short, intermediate-level review of the structure and function of the light-harvesting complex of the purple bacteria and exci-ton flow to the reaction center. 

Figure 23-27 Illustration of proposed exciton transfer of the energy of light absorbed by bacteriochlorophyll a of purple bacteria. Energy absorbed by the light harvesting complex LH2 is transferred in steps to another LH2, to LH1 and to the reaction center. The short lines within the circles represent the edges of the BChla chromophores. After Kiihlbrandt300 with permission.

It was postulated that the inhibition of LDL oxidation by red wine may help to explain the French paradox. Since Frankel and co-workers [73] showed that red wine inhibit the oxidation of LDL, several in vitro studies have confirmed this finding [26,74,75]. There is controversy over whether or not the consumption of red wine by humans reduces the oxidation of LDL ex vivo. While several studies found resistance of LDL oxidation after 2 weeks of red wine consumption in healthy subjects [75,76], others found no effect on the oxidation of LDL ex vivo [26,77]. Recently, Stein and coworkers [78] showed that short-term ingestion of purple grape juice (7.7 1.2 mL/Kg/day for 14 days) reduced the susceptibility to oxidation in coronary artery disease patients and that this is a potential mechanism by which flavonoids in purple grape products may prevent cardiovascular events, independent of alcohol content. 

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