私密直播全婐app免费大渔直播,国产av成人无码免费视频,男女同房做爰全过程高潮,国产精品自产拍在线观看

Links
Contact Info.
  • Address:天津市衛(wèi)津路94號(hào) 南開大學(xué)蒙民偉樓222室 204室
  • Zip:300071
  • Tel:022-23498126, 23502411
  • Fax:022-23498126
  • Email:weiwang@nankai.edu.cn
Current Location :> Home > Publications > Text
31. Experimental study of dynamics of topological defects in nematic polymer liquid crystals
writer:Wei Wang, Toshio Shiwaku, Takeji Hashimoto
keywords:topological defects
source:期刊
specific source:Journal of Chemical Physics
Issue time:1998年

The dynamics of stringlike defects and the shrinkage and annihilation processes of individual defect loops in a nematic polymer liquid crystal have been experimentally investigated. In 40<t<500?s, the line density of defects ρ scales as ρ(t) ∼ t−1, as expected by theory and as found in the experimental studies of some low molecular weight (LMW) liquid crystals. For individual loops, they first change their complex shape into a circle, resulting in a rapid decrease in length, and then the circular loops continuously shrink. Before a complete annihilation, the relation between the radius R(t) of the circular loop and time t0t, where t0 is the time to annihilation, is described by R2(t) = 2Γ(t0t)(t ? t0). The kinetic constant Γ determined from this polymer liquid crystal is 0.34 ∼ 0.38?μm2/s, much smaller than those (200 ∼ 300?μm2/s) obtained in some LMW liquid crystals. The small Γ is ascribed to the high viscosity of this polymer liquid crystal, compared with LMW liquid crystals.