2377 results about "Neutron" patented technology

An apparatus for selective radiation detection includes a neutron detector that facilitates detection of neutron emitters, e.g. plutonium, and the like; a gamma ray detector that facilitates detection of gamma ray sources, e.g., uranium, and the like; and/or an X-ray analyzer that facilitates detection of materials that can shield radioactive sources, e.g., lead, and the like.

An improved applanation lens and method for use in an interface between a patient's eye and a surgical laser system does not discolor or lose light transmittance when subjected to gamma radiation. The improved applanation lens has an applanation surface configured to contact the eye upon application of a pressure. The lens is formed of high purity silicon dioxide (SiO₂) with purity great enough to resist discoloration upon prolonged irradiation by high-energy radiation such as UV, x-rays, gamma rays or neutrons, and is preferably a fused silica.

In the present invention there is a provided an array of radiation detectors comprising at least one detector capable of detecting both low and high energy gamma radiation and adapted to provide spectrometric identification of the gamma source; at least one detector capable of detecting and providing spectrometric identification of fast neutrons and low resolution gamma spectra; at least one detector adapted to detect thermal neutrons; and, at least one plastic scintillator to give enhanced gamma ray sensitivity.

The presence of radiation shielding material concealing illegitimate content in a container is detected by obtaining each of measured gamma-ray data and measured neutron data from the container, and comparing the measured gamma-ray and neutron data to expected gamma-ray and neutron data. An anomaly between the measured data and the expected data is an indicum of the presence of such material shielding such illegitimate content.

A molten salt breeder reactor that has fuel conduit surrounded by a fertile blanket. The fuel salt conduit has an elongated core section that allows for the generation of electrical power on a scale comparable to commercially available nuclear reactors. The geometry of the fuel conduit is such that sub-critical conditions exist near the input and output of the fuel salt conduit and the fertile blanket surrounds the input and output of the fuel salt conduit, thereby minimizing neutron losses.

A method and apparatus for discriminating the types of radiation interacting with an integrated radiation detector having of a pulse-mode operating photosensor which is optically coupled to a gamma-ray scintillator sensor and a neutron scintillator sensor and uses an analog to digital converter (ADC) and a charge to digital converter (QDC) to determine scintillation decay times and classify radiation interactions by radiation type. The pulse processing provides for, among other things, faithful representation of the true energy spectrum of the gamma radiation field and allows for radioisotope identification by searching for the presence of characteristic energy lines in the gamma energy spectrum. The pulse shape discrimination method ensures that the high sensitivity and resolution of the isotope identification function is not affected during operation in mixed neutron-gamma fields.

Methods of forming high voltage silicon carbide power devices utilize high purity silicon carbide drift layers that are derived from high purity silicon carbide wafer material, instead of prohibitively costly epitaxially grown silicon carbide layers. The methods include forming both minority carrier and majority carrier power devices that can support greater than 10 kV blocking voltages, using drift layers having thicknesses greater than about 100 um. The drift layers are formed as boule-grown silicon carbide drift layers having a net n-type dopant concentration therein that is less than about 2×10¹⁵ cm⁻³. These n-type dopant concentrations can be achieved using neutron transmutation doping (NTD) techniques.

A method for producing ultra-pure Pu-238 is provided. The method comprises the steps of short-term irradiating Am-241 targets with a high, thermal neutron flux greater than 6.5×10¹⁴ neutrons cm⁻² s⁻¹ and more preferably greater than 1×10¹⁵ neutrons cm⁻² s⁻¹ for a predetermined period of time preferably from 20 days to 30 days and more preferably approximately 25 days to convert a substantial fraction of the Am-241 to Cm-242, e.g., approximately 0.555 g of Cm-242 per g of Am-241 charged, thereafter promptly chemically separating the produced Cm-242, preferably within 10 days to 20 days of the irradiation cycle of the Am-241 targets and more preferably within about 15 days of the irradiation cycle of the Am-241 targets, and recovering the ultra-pure Pu-238 decay product of the separated Cm-242.

The design of a compact, high-efficiency, high-flux capable compact-accelerator fusion neutron generator (FNG) is discussed. FNG's can be used in a variety of industrial analysis applications to replace the use of radioisotopes which pose higher risks to both the end user and national security. High efficiency, long lifetime, and high power-handling capability are achieved though innovative target materials and ion source technology. The device can be scaled up for neutron radiography applications, or down for borehole analysis or other compact applications. Advanced technologies such as custom neutron output energy spectrum, pulsing, and associated particle imaging can be incorporated.

A detector for detecting neutrons and gamma radiation includes a cathode that defines an interior surface and an interior volume. A conductive neutron-capturing layer is disposed on the interior surface of the cathode and a plastic housing surrounds the cathode. A plastic lid is attached to the housing and encloses the interior volume of the cathode forming an ionization chamber, into the center of which an anode extends from the plastic lid. A working gas is disposed within the ionization chamber and a high biasing voltage is connected to the cathode. Processing electronics are coupled to the anode and process current pulses which are converted into Gaussian pulses, which are either counted as neutrons or integrated as gammas, in response to whether pulse amplitude crosses a neutron threshold. The detector according to the invention may be readily fabricated into single or multilayer detector arrays.

A neutron generator includes an ion source disposed in a pressurized environment containing an ionizable gas. The ion source includes a substrate with a bundle of carbon nanotubes extending therefrom. The ends of the nanotubes are spaced from a grid. Ion source voltage supply circuitry supplies a positive voltage potential between the substrate and the grid of the ion source to cause ionization of the ionizable gas and emission of ions through the grid. An ion accelerator section is disposed between the ion source and a target. The ion accelerator section accelerates ions that pass through the grid towards the target such that collisions of the ions with the target cause the target to generate and emit neutrons therefrom. The ion source, accelerator section and target are housed in a sealed tube and preferably the carbon nanotubes of the bundle are highly ordered with at least 10⁶ carbon nanotubes per cm² that extend in a direction substantially parallel to the central axis of the tube. The neutron generator provides gas ionization at much higher atomic to molecular ratio that the prior art, which allows for small compact size designs suitable for logging tools that are used in space-constrained downhole environments.

An interpretation method and system for NMR echo-train data in thinly laminated sequences. The invention uses geological information obtained at higher vertical resolution, such as using Electric Micro Imaging, to enhance the vertical resolution of echo-train data, and thus avoids log interpretations in which the hydrocarbon potential of the formation can be misread because low resolution logs tend to provide an average description of the formation. Such averaging is especially problematic in thinly laminated sequences that consist of highly permeable and porous sand layers and less permeable silt or essentially impermeable shale layers. In a preferred embodiment, using the additional high-resolution formation information one can estimate the typical T2-spectra of lithological laminae, and significantly enhance the permeability estimate in the laminated sequences. The method and system are applicable to any temporal data from other logging tools, such as the thermal neutron decay log and others. The system and method enable proper evaluation of the high potential of thinly laminated formations, which may otherwise be overlooked as low permeable formations.

An integrated circuit, method of forming the integrated circuit and a method of testing the integrated circuit for soft-error fails. The integrated circuit includes: a silicon substrate; a dielectric layer formed over the substrate; electrically conductive wires formed in the dielectric layer, the wires interconnecting semiconductor devices formed in the substrate into circuits; and an alpha particle emitting region in the integrated circuit chip proximate to one or more of the semiconductor devices. The method includes exposing the integrated circuit to an artificial flux of thermal neutrons to cause fission of atoms in the alpha particle emitting region into alpha particles and other atoms.

A radiation source is disclosed comprising a source of charged particles that travel along a path. Target material lies along the path to generate radiation upon impact by the beam. A magnet is provided to deflect the beam prior to impacting the target. The magnet may generate a time-varying magnetic field or a constant magnetic field. A constant magnetic field may be varied spatially across the beam. The magnet may be an electromagnet or a permanent magnet. In one example, deflection of the beam results in impact of the beam on the target along a plurality of axes. In another example, portions of the beam are differentially deflected. The source may thereby irradiate an object to be scanned with more uniform radiation. The charged particles may be electrons or protons and the radiation may be X-ray or gamma ray radiation, or neutrons. Scanning systems incorporating such sources, methods of generating radiation and methods of examining objects are disclosed, as well.

Described is a multi-sensor radiation dosimeter system with (1) a self-indicating, instant radiation sensor and (2) a conventional radiation sensor for monitoring high energy radiations, such as X-ray, electrons and neutrons. Conventional radiation sensors, such as X-ray film, TLD (Thermoluminescence Dosimeters), RLG (Radioluminescence Glass) and OSL (Optically Simulated Luminescence), are highly sensitive but are not instant. In the event of a dirty bomb, nuclear detonation or a radiological accident, one needs to know the exposure instantly so proper precautions can be taken and medical treatment, if required, can be given to the victim. If a self-indicating instant sensor is one of the sensors, one would know the dose instantly, and dose can be determined with higher accuracy than by the traditional methods. This type of device offers the best of both technologies.

A solid-state detector for detection of neutron and alpha particles detector and methods for manufacturing and use thereof are described. The detector has an active region formed of a polycrystalline semiconductor compound comprising a particulate semiconductor material sensitive to neutron and alpha particles radiation imbedded in a binder. The particulate semiconductor material contains at least one element sensitive to neutron and alpha particles radiation, selected from a group including 10Boron, 6Lithium, 113Cadmium, 157Gadolinium and 199Mercury. The semiconductor compound is sandwiched between an electrode assembly configured to detect the neutron and alpha particles interacting with the bulk of the active region. The binder can be either an organic polymer binder or inorganic binder. The organic polymer binder comprises at least one polymer that can be selected from the group comprising polystyrene, polypropylene, Humiseal™ and Nylon-6. The inorganic binder can be selected from B2O3, PbO/B2O3/, Bi2O3/PbO, Borax glass, Bismuth Borate glass and Boron Oxide based glass.

This invention deals with multi-component composite materials and techniques for improved shielding of neutron and gamma radiation emitting from transuranic, high-level and low-level radioactive wastes. Selective naturally occurring mineral materials are utilized to formulate, in various proportions, multi-component composite materials. Such materials are enriched with atoms that provide a substantial cumulative absorptive capacity to absorb or shield neutron and gamma radiation of variable fluxes and energies. The use of naturally occurring minerals in synergistic combination with formulated modified cement grout matrix, polymer modified asphaltene and maltene grout matrix, and polymer modified polyurethane foam grout matrix provide the radiation shielding product. These grout matrices are used as carriers for the radiation shielding composite materials and offer desired engineering and thermal attributes for various radiation management applications.

A system and method for selecting a training data set from a set of multidimensional geophysical input data samples for training a model to predict target data. The input data may be data sets produced by a pulsed neutron logging tool at multiple depth points in a cases well. Target data may be responses of an open hole logging tool. The input data is divided into clusters. Actual target data from the training well is linked to the clusters. The linked clusters are analyzed for variance, etc. and fuzzy inference is used to select a portion of each cluster to include in a training set. The reduced set is used to train a model, such as an artificial neural network. The trained model may then be used to produce synthetic open hole logs in response to inputs of cased hole log data.

The invention relates to radiation shield concrete and a preparation method thereof. The radiation shield concrete is characterized by comprising a cementing material, coarse aggregates, fine aggregates, steel fibre, a high-efficiency slushing agent and water; the cementing material is composed of ordinary portland cement and inorganic mineral admixtures; the inorganic mineral admixtures are siliceous dust and coal ash; the fine aggregates are natural sand, boron glass powder and steel slag powder; the coarse aggregates are steel sections or a mixture of the steel sections and steel slag; the proportions of various types of components are as follows: 500 kg/m<3> of cementing material, 1400-2215 kg/m<3> of coarse aggregates, 750-950 kg/m<3> of fine aggregates, and 155-200 kg/m<3> of water; the high-efficiency slushing agent is 0.5-1.0% of the total weight of the cementing material by weight; and the steel fibre is 1.0-1.5% of the total volume of the concrete by volume. The radiation shield concrete has good mechanical property and lasting quality, good shielding effect on gamma rays, good effect on shielding neutron rays, can be used or comprehensively recycling wastes and has low cost.