Abstract: The structure serves to support any of various elements and objects, normally for translational movement. It is effectively divided, by pivot points on an intermedial axis, into two opposite portions of equal mass, thus affording to the structure immunization against translational forces transmitted through those points. The opposite portions also have their centers of gravity remotely located, so as to generate a counteracting torque in response to moments of rotational inertia transmitted through the pivot points. Integrally formed planar pieces are assembled to provide contiguous elongate elements and an interposed connecting web element, a plurality of which web elements produce a flexure joint in the structure.

Abstract: A multiplicity of one-piece flexure plates are assembled in pairs to provide a support system on which a retroreflector may be mounted for reciprocal motion. Combined with balance bodies, the flexure plates provide a support system having portions that are dynamically and statically balanced with one another, irrespective of orientation, so as to thereby immunize the unit against extraneous forces. The motion transfer assembly is especially adapted for use to support a moving retroreflector in a two-arm interferometer that may further include a beamsplitter assembly constructed from a one-piece, integrally formed body, the body having convergent, optically flat planar surfaces of specular reflectance, and means for adjustably mounting a beamsplitter therein. The spectrometer is of modular construction, and employs an integrated clocking sub-assembly as well as a light-weight voice-coil motor.

Abstract: The method and apparatus of the invention permit in situ determinations to be made of the temperature and optical constants of a substrate surface that is being treated, by measurements of radiance, reflectance and transmittance. These determinations in turn provide, at any given instant during processing, compositional and other information, thereby affording highly effective feedback control of the processing conditions. The apparatus comprises an integrated, small and relatively inexpensive instrument for process monitoring.

Abstract: The structure of the invention serves to support mirrors defining a reflective channel, which can dynamically be reciprocally widened and narrowed, as in a two-beam interferometer. It is effectively divided, by pivot points on an intermedial axis, into two opposite portions of equal mass, thus affording to the structure immunization against translational forces transmitted through those points. The opposite portions also have their centers of gravity remotely located, so as to generate a counteracting torque in response to moments of rotational inertia transmitted through the pivot points. In the structure, integrally formed planar pieces are assembled to provide contiguous elongate elements and an interposed connecting web element, a plurality of which web elements produce a flexure joint.

Abstract: The apparatus and method permit simultaneous and precise determination of the temperature and spectral emittance, over a wide spectral region, of a hot sample. Radiance, and hemispherical reflectance and transmittance measurements are employed, and FT-IR technology is advantageously applied. Reflectance and (where necessary) transmittance measurements are utilized to determine the fraction of incident radiation, of selected wavelength, that is absorbed by the sample, in turn establishing a spectral emittance value. Taken with the measured radiance at the same wavelength, the spectral emittance value will provide a quantity that can be matched with the spectral radiance of a theoretical black body, again at the selected wavelength, to thereby derive the temperature of the hot sample; this in turn enables determination of the spectral emittance of the sample over a desired spectral range.

Abstract: An aerodynamically cleaned heat-exchanger is used in heating apparatus in which the radiant energy of a dirty fuel, such as coal or char, is efficiently recovered while the exposed heat-exchange components are protected from the deleterious combustion products.

Abstract: A two-beam interferometer for Fourier spectroscopy comprises one or two reflecting channels, each having at least one relatively movable wall to vary the path length of a beam traversing the same. A beam passing through the channel makes multiple reflections therewithin, impinges upon a retroreflector, and is transferred back through the channel along the same path to recombine with a second beam, which can be similarly reflected. The multiple reflections that occur within the channel allow a large total path length change to be accomplished with a small degree of motion of the movable wall, to thereby achieve high levels of resolution.

Abstract: An optical technique for determining surface temperature utilizes the Christiansen effect that is exhibited by dielectric materials; i.e., strong absorption bands at certain wavenumber values, causing the radiance of the material to be that which would characterize a theoretical black body at that wavenumber value.

Abstract: An instrument for the chemical analysis of coal and other hydrocarbons combines TGA and FT-IR principles, and utilizes helium to carry the volatiles evolved by pyrolysis of the sample into the optical cell of the FT-IR spectrometer. The connection between the TGA furnace and the optical cell is substantially direct and non-impeding to fluid flow, and the carrier gas is preheated to the same temperature as the sample, preferably using a common heating element.

Abstract: The method and apparatus permit analyses, by optical means, of properties of gaseous suspensions of particles, by measuring radiation that is emitted, transmitted or scattered by the particles. Determinations of composition, size, temperature and spectral emittance can be performed either in-situ or by sampling, and Fourier-transform infrared spectrometric techniques are most effectively used. Apparatus specifically adapted for performing radiation scattering analyses, and for collecting radiation from different sources, are provided.

Abstract: A method and apparatus for determining the size distribution of certain particles, of a particular composition, such as iron sulfide (pyrites), in a sample of host material, such as coal. Data representative of the amount of at least one predetermined elemental constituent of the particles is obtained for each of numerous similarly-sized subsamples of the sample. The "constituent amount" data for each subsample is sorted into bins, each representative of a respective constituent amount range in a series of constituent amount ranges. Respective scaler representations of the fraction of the constituent amounts, represented by each bin range, are provided to yield an approximate representation of the distribution function of the amounts of the constituent in the subsamples of the coal. Those scaler representations collectively may provide a histogram.