Results 61 to 70 of about 5,565 (184)
Non-contact temperature measurement of a falling drop [PDF]
The 105 meter drop tube at NASA-Marshall has been used in a number of experiments to determine the effects of containerless, microgravity processing on the undercooling and solidification behavior of metals and alloys. These experiments have been limited,
Bayuzick, R. J. +2 more
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High resolution color band pyrometer ratioing [PDF]
, 1989 The sensing head of a two-color band ratioing pyrometer of a known type using a fiber optic cable to couple radiation to dual detector photodiodes is improved to have high spatial resolution by focusing the radiation received through an objective lens (i.
Bickler, Donald B. +2 more
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Noncontact true temperature measurement, 2 [PDF]
A laser pyrometer was developed for acquiring the true temperature of a levitated sample. The reflectivity is measured by first expanding the laser beam to cover the entire cross-sectional surface of the diffuse target.
Allen, James L., Lee, Mark C.
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Compensation for time fluctuations of phase modulation in a liquid-crystal-on-silicon display by process synchronization in laser materials processing [PDF]
, 2011 We demonstrate the adverse influence of temporal fluctuations of the phase modulation of a spatial light modulator (SLM) display device on nanosecond laser micromachining.
Beck, Rainer J +3 more
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CIRP Annals, 2013 Abstract This paper deals with the measurement of surface temperature on metal powder during the laser consolidation process with two-color pyrometer. Additionally, the aspect of selective laser sintering (SLS) and selective laser melting (SLM) of metal powder is visualized with high speed video camera. As a result, the surface temperature during the
Tatsuaki Furumoto +3 more
openaire +1 more source
Noncontact temperature pattern measuring device [PDF]
This invention relates to a noncontact imagine pyrometer system for obtaining the true temperature image of a given substance in a contactless fashion without making assumptions about localized emissivity of the substance or the uniformity of the ...
Allen, J. L., Elleman, D. D., Lee, M. C.
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Self-assembly of parallel atomic wires and periodic clusters of silicon on a vicinal Si(111) surface
, 2005 Silicon self-assembly at step edges in the initial stage of homoepitaxial growth on a vicinal Si(111) surface is studied by scanning tunneling microscopy (STM).
J. Ikeda +3 more
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Temperature-dependent reflectivity of silicon carbide [PDF]
The spectral reflectivity of a commercial silicon carbide (SiC) ceramic surface was measured at wavelengths from 2.5 to 14.5 microns and at temperatures ranging from 358 to 520 K using a NASA-developed multiwavelength pyrometer.
Ng, Daniel
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Thermodynamic property determination in low gravity [PDF]
Techniques for determining heat capacities and other properties of molten metals were investigated and critically evaluated. Precisely determining heat capacities calorimetrically in space poses several problems.
Margrave, J. L.
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Shock-compressed MgSiO_3 glass, enstatite, olivine, and quartz: Optical emission, temperatures, and melting [PDF]
, 2004 Optical emission of MgSiO_3 glass, enstatite, olivine, and quartz under shock wave compression was investigated with optical pyrometry at discrete wavelengths ranging from visible to near infrared.
Ahrens, Thomas J. +3 more
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