Abstract: A method and gas analysis system for a mass spectrometer including an ion pump for creating an internal vacuum within said mass spectrometer, an ionization chamber, an inlet passage through which a gas sample is introduced into the ionization chamber, valve means associated with the inlet passage for controlling the volume of gas sample introduced into the ionization chamber, a filament for introducing electrons into the ionization chamber whereby the electrons bombard the gas sample thus forming ions, an extractor plate positioned adjacent the ionization chamber and biased such that a proportion of ions and electrons are allowed to pass through the extractor plate, a quadrupole filter into which the ions and electrons are directed by the extractor plate, the quadrupole filter operative to permit a stream of ions with a pre-selected mass-to-charge ratio to pass through the filter and ions other than those having the pre-selected mass-to-charge ratio being separated from the stream of ions, means for directing

Abstract: A single blade ice skate is disclosed wherein the ice engaging blade, the toe boot plate and the heel boot plate are formed as a unitary assembly from a flat sheet of metal stock material, with the two boot plates being attached to the blade by way of twisted metal extension portions. In the initial flat state, the blade portion, the two extension portions and the two boot plates occupy a common physical plane. The two extension portions that connect the boot plates to the blade are then twisted 90.degree. in this common plane, and in a manner to place the two boot plates in planes that are normal to the plane of the blade and normal to the common plane of the initial metal stock material. The two boot plates are then bent into a U-shape, so as to provide a U-shaped vertical spring member for each of the boot plates, the spring member acting between the two boot plates and the blade (i.e.

Abstract: A method and inlet control system for controlling a gas flow sample to an evacuated chamber such as found in a mass spectrometer, is disclosed. The system utilizes a short inlet passage having an effective opening determined by a tapered diamond or steel tip needle adjacent to the inlet passage. The needle is positionally adjusted with respect to the inlet passage by being mounted on a piezoelectric crystal which is flexed by coupling thereto an electric potential derived by sensing the ions at the ionization chamber of a mass spectrometer, for example, and developing therefrom an electric signal indicative of the total pressure within the ionization chamber. The signal coupled to the piezoelectric crystal is preferably a pulse-width modulated signal with the needle maintaining the inlet passage closed except during the time that the piezoelectric crystal is flexed due to a received pulse.