Abstract: A process and system for self-calibration of a density profiler is disclosed. The process may include measuring a density profile of a fluid in a vessel using a plurality of sensors or a single sensor, and measuring a density profile of the fluid in the vessel using a plurality of sample ports. A density of the fluid proximate a location of at least one of the plurality of sample ports based on the sensor measured density profile may then be interpolated. A density of the fluid proximate a location of at least one of the plurality of sensors based on the sample port measured density profile may also be interpolated. Adjustment of a calibration of at least one of the plurality of sensors may then be made based on both the interpolated sample port density and the interpolated sensor density.

Abstract: A method for measuring a density profile of a fluid in a process vessel is disclosed. The method includes emitting gamma rays into the fluid and acquiring a backscattered gamma ray counts distribution using at least one position sensitive gamma ray detector disposed proximate the vessel. The method further includes determining the density profile of the fluid contained in the process vessel based on the backscattered gamma ray counts distribution.

Abstract: A method and apparatus in accordance with the present disclosure relate to monitoring gain of a proportional counter. The method includes generating a pulse height spectrum of the proportional counter, defining a first window and a second window within the pulse height spectrum, counting electrical pulses outputted by the proportional counter within the first window of the pulse height spectrum, thereby defining a first window count, counting electrical pulses outputted by the proportional counter within the second window of the pulse height spectrum, thereby defining a second window count, and determining a difference between the first window count and the second window count.

Abstract: A method and apparatus in accordance with the present disclosure relate to monitoring gain of a proportional counter. The method includes generating a pulse height spectrum of the proportional counter, defining a first window and a second window within the pulse height spectrum, counting electrical pulses outputted by the proportional counter within the first window of the pulse height spectrum, thereby defining a first window count, counting electrical pulses outputted by the proportional counter within the second window of the pulse height spectrum, thereby defining a second window count, and determining a difference between the first window count and the second window count.

Abstract: A method for measuring a density profile of a fluid in a process vessel is disclosed. The method includes emitting gamma rays into the fluid and acquiring a backscattered gamma ray counts distribution using at least one position sensitive gamma ray detector disposed proximate the vessel. The method further includes determining the density profile of the fluid contained in the process vessel based on the backscattered gamma ray counts distribution.

Abstract: A method for measuring high-energy radiation flux, comprising applying a low voltage to electrodes in an ion chamber filled with a fluid capable of forming ions through the interaction of the fluid with high energy radiation; measuring an ion current signal related to an ion current induced by the low voltage; determining a leakage current; determining a gain; determining a magnitude of the high-energy radiation flux based on the ion current signal, gain, and leakage current; and outputting the result of the magnitude of the high-energy radiation flux.

Abstract: An analyzer having a detector and a neutron source assembly adjacent to the detector is disclosed, wherein the neutron source assembly has a neutron source and a shielding source holder.

Abstract: A method for determining the density of a fluid that includes disposing a gamma-ray source proximate to a vessel containing the fluid is provided. The optimal position of a gamma-ray detector with respect to the gamma-ray source is determined. A gamma-ray detector is position at the optimal position, and the density of the fluid is measured.

Abstract: An analyzer having a detector and a neutron source assembly adjacent to the detector is disclosed, wherein the neutron source assembly has a neutron source and a shielding source holder.

Abstract: A method for measuring high-energy radiation flux, comprising applying a low voltage to electrodes in an ion chamber filled with a fluid capable of forming ions through the interaction of the fluid with high energy radiation; measuring an ion current signal related to an ion current induced by the low voltage; determining a leakage current; determining a gain; determining a magnitude of the high-energy radiation flux based on the ion current signal, gain, and leakage current; and outputting the result of the magnitude of the high-energy radiation flux.

Abstract: A method for determining the density of a fluid that includes disposing a gamma-ray source proximate to a vessel containing the fluid is provided. The optimal position of a gamma-ray detector with respect to the gamma-ray source is determined. A gamma-ray detector is position at the optimal position, and the density of the fluid is measured.

Abstract: A method for controlling gain of a scintillation detector includes using a reference radiation source and a photomultiplier tube and controlling the gain of the scintillation detector based on the reference radiation source. The controlling includes detecting change in the gain of the scintillation detector, determining an amount of the change in the gain, outputting a control signal to compensate the amount of the change in the gain, and stabilizing the gain against the reference radiation source based on the control signal. A gain control system for controlling gain of a scintillation detector includes computer-readable instructions stored in the memory for causing the processor to detect change in the gain of the scintillation detector determine an amount of the change in the gain, output a control signal to compensate the amount of the change in the gain, and stabilize the gain against the reference radiation source based on the control signal.

Abstract: A method for controlling gain of a scintillation detector includes using a reference radiation source and a photomultiplier tube and controlling the gain of the scintillation detector based on the reference radiation source. The controlling includes detecting change in the gain of the scintillation detector, determining an amount of the change in the gain, outputting a control signal to compensate the amount of the change in the gain, and stabilizing the gain against the reference radiation source based on the control signal. A gain control system for controlling gain of a scintillation detector includes computer-readable instructions stored in the memory for causing the processor to detect change in the gain of the scintillation detector determine an amount of the change in the gain, output a control signal to compensate the amount of the change in the gain, and stabilize the gain against the reference radiation source based on the control signal.

Abstract: An apparatus for measuring a strength of a magnetic field, including a switch including contacts configured to change position when a switching threshold is reached, wherein the switching threshold is reached by modifying an external magnetic field around the switch, and a coil wound around the switch, wherein the coil is used to modify the external magnetic field, wherein a first current is driven through the coil wound around the switch until a first switching threshold is obtained, wherein a second current is driven through the coil wound around the switch until a second switching threshold is obtained, and wherein a value of the first current when the first switching threshold is reached and a value of the second current when the second switching threshold is reached are used to determine the strength of the magnetic field.

Abstract: An apparatus for measuring a strength of a magnetic field, including a switch including contacts configured to change position when a switching threshold is reached, wherein the switching threshold is reached by modifying an external magnetic field around the switch, and a coil wound around the switch, wherein the coil is used to modify the external magnetic field, wherein a first current is driven through the coil wound around the switch until a first switching threshold is obtained, wherein a second current is driven through the coil wound around the switch until a second switching threshold is obtained, and wherein a value of the first current when the first switching threshold is reached and a value of the second current when the second switching threshold is reached are used to determine the strength of the magnetic field.

Abstract: System and methods for measuring the density, level, or interface position of a fluid or fluids in a vessel using gamma-ray backscatter are disclosed. The gamma-ray instruments disclosed may account for vessel wall buildup or deterioration. Methods disclosed herein include detecting gamma rays backscattered by a fluid from a gamma-ray source positioned proximate to a vessel with at least two gamma-ray detectors positioned proximate to the vessel and to each other; and determining a density, level, or interface value of the fluid based upon intensities of backscattered gamma rays received by the two or more gamma-ray detectors; wherein the vessel wall is subject to at least one of buildup and deterioration. The density, level, or interface may be a function of a ratio of the intensity of backscattered gamma rays received by two or more of the detectors.

Abstract: A system for measuring the density of a fluid in a vessel, the system including: at least one gamma-ray source positioned proximate to the vessel; at least one gamma-ray detector positioned proximate to the vessel, wherein the at least one gamma-ray detector is configured to detect gamma rays backscattered by the fluid from the at least one gamma-ray source; and a translator for converting the detected gamma-ray backscatter to a density value. A method to determine properties of a fluid in a vessel, the method including: positioning a gamma-ray source proximate to the vessel; positioning a gamma-ray detector proximate to the vessel; detecting gamma rays backscattered by the fluid from the gamma-ray source with the gamma-ray detector; determining a density of the fluid based upon an intensity of backscattered gamma rays received by the gamma-ray detector.

Abstract: System and methods for measuring the density, level, or interface position of a fluid or fluids in a vessel using gamma-ray backscatter are disclosed. The gamma-ray instruments disclosed may account for vessel wall buildup or deterioration. Methods disclosed herein include detecting gamma rays backscattered by a fluid from a gamma-ray source positioned proximate to a vessel with at least two gamma-ray detectors positioned proximate to the vessel and to each other; and determining a density, level, or interface value of the fluid based upon intensities of backscattered gamma rays received by the two or more gamma-ray detectors; wherein the vessel wall is subject to at least one of buildup and deterioration. The density, level, or interface may be a function of a ratio of the intensity of backscattered gamma rays received by two or more of the detectors.

Abstract: A system for measuring the density of a fluid in a vessel, the system including: at least one gamma-ray source positioned proximate to the vessel; at least one gamma-ray detector positioned proximate to the vessel, wherein the at least one gamma-ray detector is configured to detect gamma rays backscattered by the fluid from the at least one gamma-ray source; and a translator for converting the detected gamma-ray backscatter to a density value. A method to determine properties of a fluid in a vessel, the method including: positioning a gamma-ray source proximate to the vessel; positioning a gamma-ray detector proximate to the vessel; detecting gamma rays backscattered by the fluid from the gamma-ray source with the gamma-ray detector; determining a density of the fluid based upon an intensity of backscattered gamma rays received by the gamma-ray detector.