Abstract: An elemental analyzer for identifying quantities of one or more elements in a material has a container for holding a material to be analyzed, a resonant gamma ray source unit for directing resonant gamma rays into the material in the container, and at least one detector for detecting gamma rays resonantly scattered by at least one predetermined element in the material. The resonant gamma ray source unit has an outer housing of gamma ray shield and a radiological shield material, with an inner chamber and an aperture directed towards the container, a moving gamma ray generator source of predetermined materials mounted in the chamber, the materials being selected from a predetermined group of materials which emit resonant gamma rays when exposed to particles or photons, the source being directed towards said aperture, and a source of particles or photons positioned in the chamber adjacent the gamma ray generator source.

Abstract: A material analyzer for identifying quantities of one or more elements in a material has a container for holding a material to be analyzed, a resonant gamma ray source unit for directing resonant gamma rays into the material in the container, and at least one detector for detecting gamma rays resonantly scattered by at least one predetermined element in the material. The resonant gamma ray source unit has an outer housing of gamma ray shield and neutron shield material, with an inner chamber and an aperture directed towards the container, a moving gamma ray generator source of a predetermined material mounted in the chamber, the material being selected from a predetermined group of materials which emit resonant gamma rays when exposed to neutrons, the source being directed towards said aperture, and a neutron source positioned in the chamber adjacent the gamma ray generator source.

Abstract: A material analyzer for identifying quantities of one or more elements in a material has a container for holding a material to be analyzed, a resonant gamma ray source unit for directing resonant gamma rays into the material in the container, and at least one detector for detecting gamma rays resonantly scattered by at least one predetermined element in the material. The resonant gamma ray source unit has an outer housing of gamma ray shield and neutron shield material, with an inner chamber and an aperture directed towards the container, a moving gamma ray generator source of a predetermined material mounted in the chamber, the material being selected from a predetermined group of materials which emit resonant gamma rays when exposed to neutrons, the source being directed towards said aperture, and a neutron source positioned in the chamber adjacent the gamma ray generator source.

Abstract: A modular assembly for a bulk material includes container modules defining at least one radiation source cavity, at least one radiation detector channel and a passageway disposed for enabling passage of the conveyor belt through an activation region; and radiation shielding material disposed within the container means. A lower primary module contains a first portion of the radiation shielding material and defines either the radiation source cavity or the radiation detector channel. An upper primary module contains a second portion of radiation shielding material and defines the other of either the radiation source cavity or the radiation detector channel. A set of replaceable side modules contain additional portions of the radiation shielding material.

Abstract: In a bulk material analyzer in which bulk material is received in an activation region between a pair of neutron sources laterally disposed on one side of the activation region for emitting neutrons for bombarding the bulk material within the activation region to cause gamma-rays to be emitted from the bombarded bulk material and a pair of gamma-ray detectors laterally disposed on an opposite side of the activation region for detecting gamma-rays emitted from the bulk material, and in which a neutron moderator is disposed between the neutron sources and the activation region for reducing the velocity of the emitted neutrons such that the neutrons entering the activation region include thermal neutrons and faster neutrons, the uniformity of sensitivity of the bulk material analyzer to materials at different positions in a sample of the bulk material being analyzed is enhanced by controlling the proportions of thermal neutron at different positions within the sample being analyzed.

Abstract: In a bulk material analyzer in which bulk material is received in an activation region between a pair of neutron sources laterally disposed on one side of the activation region for emitting neutrons for bombarding the bulk material within the activation region to cause gamma-rays to be emitted from the bombarded bulk material and a pair of gamma-ray detectors laterally disposed on another side of the activation region for detecting gamma-rays emitted from the bulk material, a primary neutron moderator is disposed about the neutron sources for reducing the velocity of the emitted neutrons; and a secondary neutron moderator is disposed about the primary neutron moderator for further reducing the velocity of the neutrons and is further disposed adjacent the lateral edges of the activation region for channeling and reflecting the neutrons into the activation region.

Abstract: A material analyzer includes a container; a radiation source disposed within the container; a detector disposed within the container for detecting radiation that is secondarily emitted by a material sample within an activation region located between the radiation source and the detector when the material sample is bombarded by radiation from the radiation source and for producing signals in response to said secondarily emitted radiation; a computer for processing the signals to determine the content of the material sample; and a carousel for transporting a material sample from outside the container to within the activation region. The carousel is disposed about an axis of rotation located between the activation region and a receiving region located outside the container, and has a pair of sample containment chambers that are alternately moved between the receiving region and the activation region when the carousel is rotated about said axis.

Abstract: A calibration block is used for calibrating a bulk material analyzer that has an activation region in which bulk material is received for analysis and a chute for passing the bulk material through the activation region. The block is dimensioned to be of almost the same cross-sectional size as the interior of the chute and extends both above and below the activation region when inserted in the chute. The calibration block is manufactured by (a) providing a mixture of known materials of known proportions that do not chemically react with each other, including a bonding agent; (b) homogenizing the mixture to make a thick paste in which the known materials are bound without segregation of known materials that have different densities; (c) molding the homogeneous mixture into the shape of a block having predetermined dimensions; and (d) solidifying the molded mixture to provide the calibration block.