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Abstract: An array of vertically oriented multi-walled carbon nanotubes (VOMWCNT) obtained by chemical vapor deposition (CVD) on a silicon substrate without preliminary catalyst deposition has been comprehensively investigated. The synthesis was carried out for 30 min in the reactor of a carbon nanotube synthesis unit under conditions of decomposition of the reaction mixture (ferrocene in heptane) at a temperature of 800°C at a carrier gas flow rate of 200 mL/min. The structure and geometric characteristics of the array of carbon nanotubes were determined using scanning and transmission electron microscopy and Raman spectroscopy. The spectral coefficient of diffuse reflection (SDR) into the hemisphere in the wavelength range from 5.0 to 15.0 μm was determined. From the obtained experimental data, it was found that the emissivity (absorption coefficient) of an array of carbon nanotubes with a height of (230–250) μm is 0.98–0.99 in the spectral range from 5.0 to 13.7 μm and 0.975–0.995 in the range from 13.7 to 15.0 μm. Such an array of VOMWCNT can be used to develop an absolutely black body with a high absorption coefficient and small mass and size characteristics, which is used for calibrating infrared spectrometers, including on spacecraft.

This paper presents the results of a calculation of how the surface wettability of the liquid element of a liquid optical deflector affects the velocity of the liquid. It is shown that, when the surface wettability is large, the boundary of the liquid drop makes a substantial contribution to the viscous friction, and this can substantially increase the response time of the deflector.© 2004 Optical Society of America