Influence Of Temperature Distribution Research Articles

Temperature-Time Superposition of Resistivity of Carbon Fibers during Heat-treatment by Direct Currenting

The changes in the resistivity of polyacrylonitrile (PAN)-and pitch-based carbon fibers during isothermal hear-treatment by direct currenting were studied in the temperature range from 1200 to 2000 °C. By applying temperature-time superposition, smooth composite curves were obtained from the resistivity versus time curves at various temperatures. From these composite curves, the changes in the resistivity when the temperature was increased at a constant rate were calculated. The results of calculation approximated well the changes in the resistivity with temperature experimentally measured. Apparent activation energies of about 908 and 838 kJ/mol were calculated respectively for PAN-and pitch-based carbon fibers from the relation between the shift factor used for the temperature-time superposition and the surface temperature of tow. The influence of temperature distribution in tow cross-section on apparent activation energy is considered to be small. The variation of resistivity with time at a constant heat-treatment temperature was assumed as a superposition of first-order rate processes, and a rate constant spectrum was calculated.

Influence of temperature distribution along the junction plane on the lateral mode in AlGaAs phased array lasers

It is experimentally shown for the first time that far field lobe broadening, which is a multilateral mode operation under continuous wave operation in phased array lasers that emit diffraction limit beams under pulsed conditions mainly originates from temperature distribution along the junction plane. Spectrally resolved near field measurements show that pulse width, where broadening occurs, corresponds well to the one where temperature influence appears. Moreover, measurement of temperature distribution by the near field measurements and laser Raman spectroscopy show that a considerable temperature difference does exist between the center and edge elements in the array.

Influence of temperature distribution on the life of cast iron glass molds

Influence of temperature distribution on the life of cast iron glass molds

The influence of temperature distribution in a sample on thermoluminescence glow curves

This paper deals with the analysis of thermoluminescence glow curves when the distributions of temperature and concentration of trapping centers in a sample are taken into account. A check on NaCl∶MgCl2 confirms the theoretical model.

Influence of temperature distribution in the chromosphere on the spectrum of the S-component of solar radio emission

Influence of temperature distribution in the chromosphere on the spectrum of the S-component of solar radio emission

The influence of spatial temperature distribution and measuring configuration on line-reversal temperature

The influence of temperature distribution and measuring configuration on line-reversal temperature is investigated under MHD generation conditions at a seed ratio of 10 -3 and atmospheric pressure. Under these conditions, dispersion broadening occurs. In order to obtain information about the inner part of the plasma at large optical thicknesses, the width of the spectroscope inlet slit and of the spectral region covered by the photomultiplier must be made sufficiently wide.