For the first time to our knowledge, polymer-based microstructured fibers with complex cross-sections are directly produced via melt extrusion. Two principal types of fibers were fabricated: a microstructured fiber of a single polymer with a hexagonal array of air holes and a bicomponent fiber consisting of approximately 60 coaxial rings. From the latter, strong visible iridescence was observed and is shown to exhibit a mechanochromic response. This approach, the mainstay of the textile trade for decades, offers a means of continuous high-volume low-cost manufacturing of polymer (and conceivably soft-glass) fibers. For example, in the present effort, 128 coaxially microstructured fibers were fabricated simultaneously at rates exceeding 1200 m/min from industrially mainstream polymers. This approach offers an important step forward towards commoditizing microstructured fibers and open new doors for optical engineering in fashion, marking/identification, and numerous military applications.

Evaluation of the electron energy distribution in a lowpressure HgAr discharge with a twotemperature approximationHere, C,, and C,, are the rate coefficients by electron collision for excitation and deexcitation between level T and y, A,, is the spontaneous radiative transition probability, S, is the ionization rate coefficient, cr, and p, are the three-body and the radiative recombination rate coefficient, respectively,

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A method for analyzing the dynamic behavior of a low-pressure mercury rare-gas positive column is presented. An eight-state scheme analysis for mercury and argon mixture under a non-Maxwell distribution of electron energy is established. The computing time is shortened by using the two-temperature model for electron energy distribution which I have developed to give an analytical expression for the non-Maxwellian distribution. Two-temperature parameters Tt and Tb for the tail and bulk temperature, respectively, are determined from a two-term Legendre polynomial expansion of the Boltzmann equation. Then a useful empirical result is that the ratio rT=Tt/Tb is a function of a single variable of electron density times electric field strength. By storing rT calculated as a function of this variable, the electron energy distribution, which should be calculated from the Boltzmann equation at each iteration step of solving the rate equations, is found simply by a table-looking-up procedure, whereby the computing time is shortened. The examination of the eight-state scheme is done by comparing calculated and experimental results, discussing physical processes occurring among the eight states.

Evaluation of the electron energy distribution in a lowpressure HgAr discharge with a twotemperature approximation