Abstract: A sample cell insertion and removal apparatus for an analysis instrument, including a horizontally sliding frame; a sample cell carriage movably mounted to the sliding frame, the sample cell carriage including an area to hold a sample cell; wherein upon sliding into and out of the instrument, the sample cell carriage is moved horizontally and vertically into and out of an analysis position. This instrument may include a radiation shielded enclosure into and out of which the apparatus slides, and an x-ray analysis engine which transmits x-rays upwards towards the sample cell which projects from a bottom of the apparatus. 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.

Abstract: A shielded sample cell insertion and removal apparatus for an x-ray analysis instrument, including a sample cell setting to hold a sample cell, an outer surface of which exposes the sample to an x-ray engine; and a shielded area positioned over the sample cell, to shield an area beyond the sample cell from x-rays transmitted from the x-ray engine. Upon moving the apparatus into and out of the instrument, the sample cell is moved into and out of an analysis position, while retaining shielding of areas beyond the sample cell from x-rays transmitted from the x-ray engine of the instrument.

Abstract: A shielded sample cell insertion and removal apparatus for an x-ray analysis instrument, including a sample cell setting to hold a sample cell, an outer surface of which exposes the sample to an x-ray engine; and a shielded area positioned over the sample cell, to shield an area beyond the sample cell from x-rays transmitted from the x-ray engine. Upon moving the apparatus into and out of the instrument, the sample cell is moved into and out of an analysis position, while retaining shielding of areas beyond the sample cell from x-rays transmitted from the x-ray engine of the instrument.

Abstract: A sample cell insertion and removal apparatus for an analysis instrument, including a horizontally sliding frame; a sample cell carriage movably mounted to the sliding frame, the sample cell carriage including an area to hold a sample cell; wherein upon sliding into and out of the instrument, the sample cell carriage is moved horizontally and vertically into and out of an analysis position. This instrument may include a radiation shielded enclosure into and out of which the apparatus slides, and an x-ray analysis engine which transmits x-rays upwards towards the sample cell which projects from a bottom of the apparatus. 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.

Abstract: 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.

Abstract: An x-ray source assembly and method of operation are provided having enhanced output stability. The assembly includes an anode having a source spot upon which electrons impinge and a control system 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 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: A pass-through shutter mechanism enables the semiconductor crystal of an energy dispersive x-ray detector to extend beyond the shutter mechanism for analysis, adjacent to the sample, achieving optimum solid angle collection efficiency. The shutter mechanism provides optimum protection of the semiconductor detector crystal from high energy x-ray or secondary electron events produced in the chambers of electron microscopes, microprobes, x-ray spectrometers, etc.

Abstract: A radiation detector having an evacuated envelope, a radiation detector on a cold finger support in the evacuated space, a closed cycle gas cooling system to cool the cold finger to provide cryogenic operation of the radiation detector, and a getter in the evacuated space to maintain an evacuated condition. The evacuated envelope includes a radiation window. The radiation detector is preferably an X-ray detector employed in an energy dispersive spectrometry system. The evacuated space is preferably held at a pressure of less than about 1 mTorr to achieve molecular flow of remaining gas molecules, minimizing parasitic heat input. The closed cycle gas cooling system employs compressed refrigerant, which is precooled in a counterflow heat exchanger and allowed to expand in proximity to the cold finger, thus absorbing heat and maintaining cryogenic temperatures. A getter material, preferably activated carbon, is provided to absorb gasses and maintain the low pressure during operation.

Abstract: A matched thermal expansion support system for cryogenically cooled x-ray spectrometers is described for the purpose of holding x-ray detecting crystals precisely in position throughout large temperature changes. This thermal matching is achieved by a detector holder, having an axial thermal movement characteristic, mounted on a support having an equal, but opposite, thermal movement characteristic.

Abstract: An inner vessel having a truncated triangular volume is spaced from an outer housing of similar shape to form a chamber therebetween. A thermally conductive strap is connected at one end to the vessel at its other end to a cold finger tube extending into the chamber. The vessel contains liquid nitrogen and is secured in spaced relationship from the outer housing by a fiberglass liquid nitrogen fill tube. An electronic assembly for processing signals generated by the detector cooled by the cold finger are aligned with the cold finger external the dewar housing. The dewar accommodates entry port angles between zero and 60.degree. for different microscopes without physical interference with the microscope housing and attachments.

Abstract: An X-ray radiation detector is thermally conductively secured to the end of a cryogenically cooled copper cold finger in an evacuated atmosphere. A collimator having a conical radiation conduit at a relatively low evacuated pressure is thermally conductively secured to the end of the cold finger for passing radiation emitted by an electron microscope and reflected from a specimen to the detector in a windowless environment. The collimator and cold finger are at about the same cryogenic temperature. The detector is maintained at a temperature of a few degrees C. above that of the collimator. The collimator conduit radiation ingress aperture is dimensioned to limit gas flow to the conduit to limit moisture flow into the conduit and to the detector, the gas flow being molecular in a low pressure atmosphere.

Abstract: Parallel heat paths are provided by three nested tubes, the outer tube being of stainless steel and connected cantilevered to a housing at ambient temperature. The innermost tube forms a cold finger having a negligible temperature gradient and secured in thermal conductive isolation concentrically within an intermediate cold sleeve tube which is also concentric within the outer tube, the cold finger and cold sleeve tubes being made of copper. The tubes have a minimum diameter and specular facing surfaces to minimize radiation coupling which is the major source of heat transfer between the tubes. The two inner tubes have minimum thermal conductive coupling via thermal insulating tapered rings at one end and a thermal insulating support at the other end. A radiation detector is secured to the inner cold finger tube for receiving X-ray radiation from a specimen in an electron microscope. The other ends of the two inner tubes ar thermally conductively connected to a heat sink Dewar via braided copper straps.