Abstract: A vibration monitoring system employing a capacitive accelerometer determines the energy associated with one or more frequency components within the frequency spectrum of the vibration signal. The capacitive accelerometer operates as a mixer due to its time varying capacitance which provides a measure of the vibration. When the accelerometer is excited by an AC signal the output from the accelerometer comprises beat frequencies due to the mixing of the time varying capacitance and the AC signal. By changing the frequency of the AC signal the location of the beat frequencies in the frequency domain of the accelerometer output can be shifted. Subsequent bandpass filtering to attenuate frequencies except those associated with the frequency component and demodulation to bandshift the energy of the filtered signal energy to DC, creates a DC value which provides a measure of the energy present at the frequency component.

Abstract: Apparatus for, and method of, hydrostatically testing whether a line filled with a liquid, such as gasoline, is leaking comprising mechanism for closing one end of the line to be tested and an upstanding cylinder having its upper end coupled to the opposite end of the line to be tested. The cylinder is transparent and filled at its upper end with a liquid identical to the liquid in the line being tested and at its lower end, a second liquid of a substantially heavier density so that the liquids do not mix. Mechanism is provided for applying pressure to the heavier density liquid to force the liquid in the upper end of the cylinder into the line. The cylinder is transparent and includes graduations thereon so that the user can visualize whether or not the junction is moving.

Abstract: A method for the direct presentation of a differential measured quantity, in particular, a differential gas concentration measurement, in terms of its correct physical unit is disclosed. A characteristic curve representing the output of a gas sensor detector as a function of gas concentration is obtained in an absolute coordinate system. A reference level at which the differential measurement is to occur is defined on this characteristic curve by a defined input or, respectively, output value. This reference level defines the origin of a differential coordinate system from which the differential measurement may be directly ascertained.

Abstract: A humidity meter includes a humidity-frequency converter which is essentially a pulse oscillator, the frequency of which depends upon the impedance of a humidity sensor, a pulse width modulator for adjusting pulse width of an output pulse of the converter for assuring a linear relationship between humidity and the output signal, and an integrator for integrating the output of the pulse width modulator to provide an output signal as a DC level. A feedback path is provided to apply the output signal to the pulse width modulator for assuring a linear output irrespective of the exponential characteristics of the humidity sensor.

Abstract: Method and apparatus for non-destructive testing the quality of manufactured wood panels which includes supporting the panel so as to have a portion thereof in cantilevered fashion. The cantilevered portion of the panel is caused to vibrate so as to include complex vibrations that include both twisting and bending. The vibrations in the panel are sensed providing an output signal that is fed to analyzers and computers to determine from the simultaneously induced bending and twisting vibrations respectively the modulus of elasticity and shear modulus of the panel. Two different forms of apparatus are illustrated, one of which requires the panel to be stationary while being tested and the other in which the panel moves continuously while vibrations are induced and the induced vibrations sensed.

Abstract: An analyzer includes a test cell which contains a core of coal from a coal bed methane reservoir. A tomographic system is used for testing the core at different times and provides signals corresponding to the tests. While the earthen core is being tested, a fluid having the same size molecules as methane is provided to the earthen core as part of the testing. The signals from the tomographic system are used to determine the methane storage capacity of the core.

Abstract: A method of discriminating alcohols different from ethanol in breath samples includes sampling voltages from a fuel cell at a rapid rate to establish a curve rising, upon introduction of a sample containing a known amount of ethanol without interferants, from an initial base line to a peak; determining a peak voltage; establishing an end point; determining the area under the curve from the introduction of the sample to the end point, and determing at least two other areas under the curve between the peak and the end point, a peak area, between the peak and a point on the curve relatively near the peak, and a trail area, between the end point and a point nearer the end point than the peak area; introducing to the fuel cell a breath sample that may contain an interferant in the form of an alcohol different from ethanol, and determining the peak voltage, end point, total area, peak area and trail area using the same criteria as were used in determining those pieces of information in connection with the sample co

Abstract: A highly sensitive and selective electrochemical detector has been developed for the liquid chromatograph analysis of carbohydrates. This detector includes copper particles and copper particles coated with copper oxide particles dispersed in a perfluorosulfonate ionomer film which is cast onto the surface of a glassy carbon electrode. The copper is electrochemically dispersed into the perfluorosulfonate ionomer by a constant potential method. The response of the detector is based on the electrolytic generation of a higher oxidation state species of copper catalytically oxidizing carbohydrates in alkaline solutions at a pH greater than 13.