Polymers are usually considered thermal insulators, because the amorphous arrangement of the molecular chains reduces the mean free path of heat-conducting phonons. The most common method to increase thermal conductivity is to draw polymeric fibres, which increases chain alignment and crystallinity, but creates a material that currently has limited thermal applications. Here we show that pure polythiophene nanofibres can have a thermal conductivity up to ∼ 4.
View Article and Find Full Text PDFPhase imaging is used to compare near-field measurements with the corresponding far-field intensity distribution. A liquid-crystal device serves as a phase object that can be programmed as a variable grating. Real-time phase visualization then provides an avenue for direct optimization of complex phase gratings.
View Article and Find Full Text PDFEfficient, electrically tunable, agile, inertialess, near-diffraction-limited one-dimensional optical beam steering is demonstrated at the infrared wavelength of 10.6 microm with a liquid-crystal phased array.
View Article and Find Full Text PDFPhys Rev C Nucl Phys
October 1993
Phase retardance of a liquid-crystal-based, electrically tunable wave plate as a function of voltage and incident light intensity at 10.6 microm is measured using the Stokes-MacCullaugh ellipsometry technique. At intensities of up to 900 W/cm(2), device performance is found to be driven by thermal effects and not optically induced reorientation effects.
View Article and Find Full Text PDFCancer Immunol Immunother
November 1983
An immunoperoxidase study was carried out on human tonsil (15 specimens) and human lymph node (5 specimens) using OKT6, a monoclonal antibody which was raised against a determinant on immature thymocytes. OKT6-positive cells were identified in the crypt epithelium of all tonsils examined and in occasional clusters in the interfollicular areas of two lymph nodes. OKT6 has recently been shown to react with epidermal dendritic cells (Langerhans' cells).
View Article and Find Full Text PDFAnn Otol Rhinol Laryngol
March 1966