Concentration Fluctuations in a Polymer Solution under a Temperature Gradient
نویسندگان
چکیده
We have performed small-angle Rayleigh light-scattering measurements in polymer solutions under various externally applied temperature gradients. Our experiments confirm the existence of an enhancement of the concentration fluctuations. The nonequilibrium concentration fluctuations are proportional to s=Td2yk4, where =T is the applied temperature gradient, and k is the wave number of the fluctuations. The measured strengths of the nonequilibrium fluctuations in the dilute and semidilute concentration regime agree with the strengths calculated from fluctuating hydrodynamics. [S0031-9007(98)08007-7]
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