摘要:
A sample cell for an analysis instrument, having an outer body forming a sample reservoir therein; a directional fill valve disposed in an upper end of the outer body and forming an upper end of the sample reservoir, the fill valve for accepting a sample during filling, and preventing sample leakage while providing venting after filling; and a film covering a lower end of the outer body, and forming a bottom end of the sample reservoir, the film for presenting the sample to an analysis focal spot of the analysis instrument. The disclosed sample cell is especially suited for an x-ray analysis engine having a focal spot requiring alignment with the sample in the sample cell. At least one x-ray optic may be disposed in an excitation and/or detection path, requiring alignment to the focal spot, in e.g., a WDXRF or EDXRF system.
摘要:
An x-ray source assembly (2700) and method of operation are provided having enhanced output stability. The assembly includes an anode (2125) having a source spot upon which electrons (2120) impinge and a control system (2715/2720) for controlling position of the anode source spot relative to an output structure. The control system can maintain the anode source spot location relative to the output structure (2710) notwithstanding a change in one or more operating conditions of the x-ray source assembly. One aspect of the disclosed invention is most amenable to the analysis of sulfur in petroleum-based fuels.
摘要:
A method and device for cooling and electrically-insulating a high-voltage, heat-generating component, for example, an x-ray tube (1105) for analyzing fluids by means of x-ray fluorescence. The device includes an x-ray source (1100) including an x-ray tube (1105) having improved heat-dissipating properties due to the thermal coupling of the x-ray tube with a thermally-conductive, dielectric material (1150). The device may include a base assembly (1135) mounted to the component for conducting heat away from the component while electrically isolating the component. In one aspect of the invention, the base assembly includes two copper plates (1140, 1145) separated by a dielectric plate (1150). The dielectric plate minimizes or prevents the leakage of current through the base assembly (1135). One aspect of the disclosed invention is most amenable to the analysis of sulfur in petroleum-based fuels.
摘要:
A method and device for cooling and electrically-insulating a high-voltage, heat-generating component, for example, an x-ray tube (1105) for analyzing fluids by means of x-ray fluorescence. The device includes an x-ray source (1100) including an x-ray tube (1105) having improved heat-dissipating properties due to the thermal coupling of the x-ray tube with a thermally-conductive, dielectric material (1150). The device may include a base assembly (1135) mounted to the component for conducting heat away from the component while electrically isolating the component. In one aspect of the invention, the base assembly includes two copper plates (1140, 1145) separated by a dielectric plate (1150). The dielectric plate minimizes or prevents the leakage of current through the base assembly (1135). One aspect of the disclosed invention is most amenable to the analysis of sulfur in petroleum-based fuels.
摘要:
A method and apparatus for analyzing fluids by means of x-ray fluorescence. The method and apparatus are applicable to any fluid, including liquids and gases, having at least one component that emits x-ray fluorescence when exposed to x-rays. The apparatus includes an x-ray source (82) including an x-ray tube (64) having improved heat dissipating properties due to the thermal coupling of the x-ray tube with a thermally-conductive, dielectric material (70, 1150). The x-ray tube also includes means for aligning (100, 2150, 2715) the x-ray tube with the x-ray source housing whereby the orientation of the x-ray beam produced by the x-ray source can be optimized, and stabilized various over operating conditions. The method and apparatus may also include an x-ray detector having a small-area, for example, a PIN-diode type semiconductor x-ray detector (120), that can provide effective x-ray detection at room temperature. One aspect of the disclosed invention is most amenable to the analysis of sulfur in petroleum-based fuels.
摘要:
Methods and devices for aligning an x-ray optic with a source of x-rays and methods and devices for determining a focusing characteristic of an x-ray optic are provided. The methods and devices simplify the process of aligning an x-ray optic device (for example, a polycapillary x-ray optic) to an x-ray source or for measuring a focusing characteristic, for example, the focal length or beam shape, of an x-ray optic. In one aspect, the device includes a housing having a first aperture adapted for receiving an x-ray optic and a surface having an x-ray flourescent material from which visual fluorescence occurs when impinged by x-rays. The size and shape of fluorescence from the surface may be varied by moving the surface to determine, for example, the focal length of the x-ray optic.
摘要:
An x-ray analysis apparatus for illuminating a sample spot with an x-ray beam. An x-ray tube is provided having a source spot from which a diverging x-ray beam is produced, the source spot requiring alignment along a transmission axis passing through the sample spot. A first housing section is provided, to which the x-ray tube is attached, including mounting features for adjustably mounting the x-ray tube therein such that the source spot coincides with the transmission axis. A second housing section includes a second axis coinciding with the transmission axis; and at least one x-ray optic attached to the second housing section for receiving the diverging x-ray beam and directing the beam toward the sample spot. Complimentary mating surfaces may be provided to align the first and second sections, and the optics, to the transmission axis. A third housing section may also be provided, including an aperture through which the x-ray beam passes, and to which a detector may be attached.
摘要:
A measurement and processing technique enabling x-ray analysis systems to handle dynamically changing samples and other conditions resulting in both significant and insignificant measurement changes. A stream of input values related to measured compositional information of the sample is received, and a stream of output compositional values is produced. The current output value y[n] is set as a function of the received input value x[n] if the received input value x[n] differs from x[n−1] by more than an intensity-dependent deviation limit; and alternatively the current output y[n] is set as a function of the previous output y[n−1] and the received input value x[n] if the received input value x[n] differs from x[n−1] by less than the intensity-dependent deviation limit. The intensity-dependent deviation limit is maintained as a function of the intensity of the measured compositional information. Types of dynamically changing samples to which the technique is applicable include fluid streams and sheet production, monitored by, e.g., XRF and XRD systems.
摘要:
A technique for analyzing fluids by means of x-ray fluorescence applicable to any fluid, including liquids and gases, which emit x-ray fluorescence when exposed to x-rays. The apparatus includes an x-ray source (82) including an x-ray tube (64) having improved heat dissipating properties due to a thermally-conductive, dielectric material (70, 1150). The x-ray tube also includes means for aligning (100, 2150, 2715) the tube with the source housing whereby the orientation of the x-ray beam produced by the source can be optimized, and stabilized over various operating conditions. The method and apparatus may also include an x-ray detector having a small-area, for example, a PIN-diode type semiconductor x-ray detector (120), that can provide effective x-ray detection at room temperature. One aspect of the disclosed invention is most amenable to the analysis of sulfur in petroleum-based fuels.