Abstract:
A dosimeter is described that does not show differences in sensitivity over its sensitive area when ambient pressure changes. To that purpose the measuring chamber and a pressure compensation element together form a single gastight chamber having at least partially walls of soft material. Thereby the pressure inside the measuring chamber is essentially equal to ambient pressure whereby no mechanical distortion of the measuring chamber over its sensitive area takes place.
Abstract:
A probe assembly is disclosed comprising an inlet for receiving an eluent from a chromatography device; an outlet for delivering the eluent to an ion source of a mass spectrometer; and an attachment device for attaching the outlet to the mass spectrometer. The outlet comprises an electrically conductive capillary and an electrically conductive member surrounding at least part of the electrically conductive capillary. The electrically conductive member is arranged to receive a voltage upon connection of the attachment device to the mass spectrometer and the electrically conductive member is arranged to provide an electrical connection from the electrically conductive member to the electrically conductive capillary.
Abstract:
A method of and system for analyzing ion mobility of a sample. The sample is received by an ionization chamber, which ionizes molecules of the sample. The ionized sample is received from the ionization chamber by a drift tube coupled to the ionization chamber and propelled along a length of the drift tube in a first direction away from the ionization chamber by an electric field gradient of the drift tube. A magnitude of the electric field gradient is in view of an atmospheric pressure measurement. A drift gas is propelled through the drift tube in a second direction opposite the first direction such that different types of ionized molecules travel through the drift tube at different rates. An arrival time of each of the different types of molecules at a detector located at a second end of the drift tube opposite the first end is detected.
Abstract:
A Geiger-Mueller ("GM") tube containing a noble gas mixture of about 98-99.9% Ne and the remainder Ar, and in addition containing from 2-5% ethylene as the quench gas, provides high stability and high count rates in the temperature range from about -100.degree. C. to about 200.degree. C. When this GM tube is provided with a sleeve-and-screen liner in electrical contact with an outer cathode, the tube exhibits exceptional sensitivity. The sleeve may be a continuous deposit of a heavy metal having an atomic number from about 73 to about 83, deposited on the inner surface of the cathode tube, or the sleeve may be a foil liner of tungsten or tantalum. The screen is woven of metal wire on which is deposited a heavy metal.
Abstract:
A direct ion storage (DIS) radiation detector or dosimeter has a design that is easy and low cost to manufacture using semiconductor processing techniques. The detectors include internal communications interfaces so they are easy to read. Different interfaces, including wired, e.g. USB ports, and wireless interfaces, may be used, so that the dosimeters may be read over the internet. The detectors can thus be deployed or used in a variety of detection systems and screening methods, including periodic or single time screening of people, objects, or containers at a location by means of affixed dosimeters; screening of objects, containers or people at a series of locations by means of affixed dosimeters, and surveillance of an area by monitoring moving dosimeters affixed to people or vehicles.
Abstract:
A direct ion storage (DIS) radiation detector or dosimeter has a design that is easy and low cost to manufacture using semiconductor processing techniques. The detectors include internal communications interfaces so they are easy to read. Different interfaces, including wired, e.g. USB ports, and wireless interfaces, may be used, so that the dosimeters may be read over the internet. The detectors can thus be deployed or used in a variety of detection systems and screening methods, including periodic or single time screening of people, objects, or containers at a location by means of affixed dosimeters; screening of objects, containers or people at a series of locations by means of affixed dosimeters, and surveillance of an area by monitoring moving dosimeters affixed to people or vehicles.