Correlation time measurements

D. Axelson Based on correlation time measurements the upper limit Tg s that we report are frequency-independent. The results would only be surprising to those who argue for a much higher Tg for the polyethylenes. 

Isotropic rotation correlation time measured for the V02+-substituted DTPA complex [4]. 

Rotational diffusion is characterized by the mean square angular deviation during the time interval At (0 ) = GDrAi. Highly anisotropic motion, which is typical for lipid molecules in the membrane, is usually described by two rotational diffusion coefficients Dr and Dri, which correspond to diffusion about the long diffusion axis and perpendicular to it, respectively. The diffusion coefficients are related to corresponding rotational correlation times measured by nuclear magnetic resonance (NMR), electron spin resonance (ESR), fluorescent depolarization, and so on, as ... 

The rotational correlation time ((j)p) of myoglobin is equal to 9.2 and 5.5 ns at 15 and 35°C. The fluorescence lifetime (17.8 ns) of the porphyrin inside the myoglobin molecule is about twice the value of (j)p. Thus, a Perrin plot representation obtained by varying the temperature should enable us to obtain a correct experimental value of (j)p. In fact, during the fluorescence lifetime, the protein has enough time to make a complete rotation around it axis, independently of whetlier porphyrin displays free motions or not. In fact, the rotational correlation time measured from the Perrin plot at 15 and 35°C are in good agreement with those calculated theoretically (see Table 9.6). 

Rotational correlation times measured in several solvents and in micelles. 

Measurement of interaction with protein. ) Measurement of rotational correlation time in H2O, dodecane, and solutions of sodium dodecyl sulfate and other surfactants. Measurement of rotational correlation times in starch solution at several temperatures. Measurement of rotational correlation times. ) Measurement in phosphatidyl choline vesicle membranes. Several related radicals also used. ) Measurement of effect of temperature on line broadening. Rotational correlation time measured in solutions of sodium dodecyl sulfate. ) Measurement of hemimicelle formation of surfactant SDS adsorbed onto alumina. ) Measurements in phase V liquid crystal solvents 7 other related radicals measured. 86Szal, 83Brol ), 87Bag2 )... 

Line shape analysis and rotational correlation time measurements in liquid-crystal polyester and in hexakis(hexyloxy)triphenylene discotic mesophase. ) Exchange frequency 17,20,1000 MHz. 

Measurement of rotational correlation times in starch solution at several temperatures Measurement of rotational diffusion times in glass transition of dibutyl phthalate Measurement of rotational correlation times Measurement of rotational diffusion Study of H-bonding to CF3CH2OH and measurement of rotational correlation times Study of H-bonding to (CF3) COH... 

Measurement of rotational correlation times. Measurement in isotropic and nematic phases. FT analysis of spectrum. 

Correlation time measurements measurements also in 1,3-propanediol. 2H(3,5) -0.049 ... 

Rotational correlation times measured in sodium dodecyl, octyl and hexadecyl sulfate. ) Measurements of linewidth in (C4p9)3N with and without O2 being present. 

Rotational correlation time measurements. Measurement of mean residence time in micelles. ... 

When intramolecular motion occurs at rates comparable to or greater than the rate of overall molecular motion, the correlation time measured from the value will be an effective correlation time comprising contributions from the internal (ii t) and overall motions (imoi)- In the extreme narrowing condition (co t I) the observed spin-lattice relaxation time for a rapidly rotating methyl group attached to an isotropically reorienting molecule will be (Doddrell et al, 1972) ... 

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