INDEX conjugated dienes

Much experience concerning the hydrogenation of conjugated dienes was obtained with butadiene hydrogenation. On Pt single crystals the reaction was found to be structure sensitive the activity sequence of different planes (marked with Miller s index) is... 

At higher temperatures the tertiary. chloride undergoes a rearrangement under the influence of CuCl giving a chloride with a conjugated diene system. This isomer has a considerably higher refractive index. 

Reversed-phase HPLC has been used to analyze the oxidation products of triacylglycerols in edible oils. The detection is often based on monitoring the conjugated dienes with an ultraviolet detector (234-235 nm). However, the UV detector provides no information about oxidation products without a conjugated diene structure, e.g., products of oleic acid. Information about these compounds is important when oils with a high oleic acid content are studied. The most common universal detector types—refractive index and flame ionization detectors—are not sensitive enough to detect small amounts of oxidation products. 

Dielectric constant A value that serves as an index of the ability of a substance to resist the transmission of an electrostatic force from one charged body to another the lower the value, the greater the resistance. Diels-Alder reation A reaction involving the addition of an ethylenic double bond to a conjugated diene. 

Many authors have concluded that the conjugated diene method might be used as an index of stability of lipids in place of, or in addition to PV. It is faster than iodometric PV determination, much simpler, does not depend on chemical reactions or color development, and requires a smaller sample size. However, the presence of compounds absorbing in the region of the conjugated diene formation may interfere with such determinations. It has been proposed that interference in complex systems can be minimized or eliminated by derivative spectroscopy, using photodiode detection of spectra and computer analysis of the data. ... 

The polymer name may consist of as many as four parts (1) the primary source material, under which the polymer is indexed (2) the functional type, that is, the type of functionality incorporated into the backbone (3) the co-reagent and (4) the structure designation. The structure designation is necessary because more than one mode of polymer formation may be possible from the same source materials. Structural isomers, geometrical isomers, and stereoisomers must be differentiated, as well as structures which are not isomeric. The different polymer structures which may be formed in the polymerizations of conjugated dienes are designated as shown in the case of 1,3-butadiene ... 

In the case of photoexcited fullerenes C60 and fullerene C60-containing composites in incubation medium of thymocytes, the indexes of LPO did not alter compared to the control too (Fig. 6.2A). Upon incubation of EAC cells in the presence of photoexcited samples of fullerenes, the decrease in the content of diene conjugates by 35% in the presence of fullerene C60 and by 20% in the presence of fullerene C60-composite-1 and fullerene C60-composite-2 was observed (Fig. 6.2B). The presence of photoexcited samples of fullerenes in the suspension of L1210 cells influenced LPO indexes only in the presence of fullerene C60-composite-2, when the content of diene conjugates increased by 35% (Fig 6.2C). 

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