Abstract: A compact medical nuclear imaging device, which generates a medical image from gamma radiation, can be held stationary or moved to search a large area for locating a radioactive area of interest. The compact medical imaging device comprises a collimator having an array of collimating channels, a radiation collection module converting the gamma radiation to an electric signal, an electronic module for processing the electrical signal, and a display module for displaying a two-dimensional image of the radiation scene, all of which preferably are assembled together in a single, compact module of a size small enough to permit it to be held and maneuvered by a human operator.

Abstract: A scintillation detector having reduced temperature sensitivity is provided by having two circuits for temperature compensation. The two circuits may be a thermistor in parallel with both a resistive element and a switching element. The switching element can be various devices including a zener diode, a Schottky barrier diode or an MIM. The temperature compensation circuit may be included in the circuit of a photo-detector such as a photomultiplier tube.

Abstract: A sparger includes a conduit for conducting an oxygen feed, a nozzle connected to the conduit for passage of the oxygen feed from the conduit to the outside of the sparger, the nozzle including an orifice and a shroud, and insulation surrounding the conduit and also the shroud substantially the full length of the shroud. A method is provided for producing acrylonitrile via propane ammoxidation, comprising introducing propane and ammonia feeds into a fluid bed of a fluid bed reactor, and introducing an oxygen feed into the fluid bed through at least one insulated and jacketed sparger nozzle for reacting with at least one of the propane feed and ammonia feed in the presence of a fluid bed catalyst.

Abstract: A scintillation detector includes a scintillation crystal directly coupled to a photomultiplier tube (PMT). The crystal/PMT subassembly is attached to a voltage divider and the entire device is hermetically sealed in a stainless steel outer case. Conductors are passed through the hermetic package from the voltage divider via a high temperature metal to ceramic pass-through. The crystal and PMT are longitudinally loaded within the outer case by springs in order to minimize vibrations in the crystal and PMT. A thermoplastic support sleeve circumscribes the crystal and the PMT to protect the crystal and PMT from excessive longitudinal loading. Preferably, the support sleeve and the crystal have similar coefficients of thermal expansion so that the crystal and the support sleeve experience similar dimensional changes due to temperature fluctuations, allowing the support sleeve to best maintain its stress-limiting function as temperature within the detector changes.

Abstract: A well logging instrument and method that remove vibration induced noise from the output of a detector including a scintillation crystal. The invention is based on a realization that pulses induced by vibration during MWD operations are characteristically periodic, whereas pulses generated down hole by gamma rays occur at random intervals and are characteristically non-periodic. The instrument and method involve positioning a scintillation crystal package in the high vibration environment for interaction with incident radiation, using a light sensing device to convert photons received from the scintillation crystal package into an electrical signal which over time is composed of radiation induced events that are non-periodic and vibration induced events that are periodic, distinguishing the periodic events using a time history of the electrical signal, and removing the periodic events from the electrical signal to provide a corrected electrical signal from which vibration induced components have been removed.

Abstract: A radiation detection system and method for scanning an object for ionizing radiation are generally characterized by at least one radiation detector which provides an output related to the level of ionizing radiation impinging thereon, a sensing device which evaluates and provides an output related to a shape characteristic of an object being scanned by the radiation detector, and a processor operatively connected to the radiation detector and sensing device for processing the outputs thereof. The output of the sensing device is used to compensate for variations in ambient background level arising from the sensed shape characteristic of the object. With such a system, the possibility of a geometry induced false alarm is minimized. In a preferred embodiment adapted for dynamic vehicle monitoring, the sensing device is a level detector operative to detect the level of the material in a truck or rail car passing by the radiation detector or detectors.

Abstract: A radiation monitoring system and method characterized by the use of paired active and passive radiation detectors to monitor exposure to a radiation field. The active detector provides an output representative of radiation exposure on a real time basis while the passive detector is readable on a delayed basis after exposure to radiation for a period of time to provide an output representative of radiation exposure over said period of time. Respective readers are provided for extracting the radiation exposure information from the detectors, as is a processor which determines a quantity of radiation exposure from the radiation information extracted from the detectors. The processor corrects radiation exposure data derived from one of the detectors using radiation exposure data derived from the other of the detectors.

Abstract: A dosimetry system and method characterized by use a plurality of radiation sensitive elements to monitor exposure to a radiation field composed of one or more types of radiation at one or more different energies; reading the radiation sensitive elements in a reader after irradiation by the radiation field to obtain element outputs; and supplying the element outputs to a trained neural network computer apparatus wherein the element outputs are analyzed to provide an output indicative of the radiation field.

Abstract: A brake and wheel assembly wherein the available piston stroke for a given envelope can be significantly increased to provide greater brake life between overhauls. The wheel and brake assembly is characterized by a fluid actuated back leg structure which allows a disk pack to be compressed and adjusted not only from its brake head side as is conventional but also from its wheel side. As the brake wears, the back leg structure draws the wheel side of the disk pack toward the brake head while the brake actuator piston or pistons push the disk pack in the wheel direction.

Abstract: A fiber optic harness assembly having reduced weight and bulk comprises a plurality of optical fibers and loose tube protective buffers therefor. At least two of the optical fibers and corresponding buffers are routed commonly along a first branch of the harness and respectively along the second and third branches of the harness. Similarly, strength elements extending parallel to corresponding optical fibers are routed commonly along the first branch to the intersection whereat the strength elements are divided into separate portions for extension respectively along the second and third branches. The strength elements and buffered optical fibers coextending along the harness branches are surrounded and held bundled together in contiguous relationship by respective branch portions of an outer jacket or sheath.