Abstract: Apparatus for analysing a sample comprises: a. A radiation source for generating a radiation beam; b. A sample holder for holding the sample in use; c. A polariser for polarising the radiation beam; d. A radiation beam selector for selectively exposing the sample to either the radiation beam or the polarised radiation beam; and, e. A detector for detecting radiation emitted by the sample.

Abstract: An image reading apparatus having a visible light source for emitting visible light, an invisible light source for emitting invisible light, an imaging optical system for irradiating a document by these light sources to form optical images of the document, and a CCD for photoelectrically converting the optical images Of the document turns on the visible light source to acquire a visible light image signal by the CCD. Then, the apparatus turns on the invisible light source to acquire an invisible light image signal by the CCD. After the invisible light image signal is acquired, the apparatus turns off the invisible light source, and turns on the visible light source regardless of whether to read the document.

Abstract: Described are preferred devices and systems useful in the non-destructive detection of predetermined substances, such as plastique explosives, in objects under interrogation. The devices and systems are readily constructed and can be manufactured as self-contained, portable detection devices.

Abstract: An image processing apparatus for processing visible image information and invisible image information obtained from visible light and invisible light directed onto an original and from the original onto an image pick-up element via a focusing optical system. The image processing apparatus includes an infrared light source, a visible light source, a focus correction unit that corrects the focus of the images when the images are formed on the image pick-up element and acquired, and a signal processor that corrects a partial magnification difference between the visible image and the infrared image.

Abstract: In an image processing device which carries out processing for detecting and correcting defective portions of an image, it is possible to pre-emptively prevent the defective portion detecting and correcting processing from causing a deterioration in image quality or an excessive processing requiring time requirement. In cases in which a film type of a photographic film on which the image is recorded is a film type known to have a characteristic that an IR image is also formed at a time of image exposure and recording, and in cases in which a density distribution width of IR data is a predetermined value or more, defect detection-correction processing is cancelled. Further, in cases in which a non-image region is included in the image, either defect detection-correction is carried out only on regions other than the non-image region, or defective portion detection-correction is cancelled.

Abstract: A method for non-invasive measurement of the velocity of a medium selected from either a gas or a fluid at an examination location by boosting atoms and molecules of the medium into an excited atomic or molecular state with a focused first pulsed light beam in the investigation location, allowing the excited atoms and/or molecules to relax into a metastable state and then boosting the atoms and/or molecules in the metastable state into an excited atomic or molecular state with a second pulsed light beam that is weaker than the intensity of the first beam to transirradiate the investigation location and to produce a characteristic luminescence, detecting the characteristic luminescence of the selectively excited atoms and/or molecules and determining the coordinates of the investigation location and of the occurrence of the luminescence of a luminescent cloud in an image field and then calculating the velocity of the medium on the basis of the distance between the investigation location and the mid-point of th

Abstract: Methods for quantifying the irradiation dose received by an item or items, such as food items and medical items, undergoing irradiation-based sterilization, includes the steps of monitoring a selected electronic parameter associated with an economic single use sensor positioned adjacent the item or items and telemetrically relaying data associated with the monitored electronic parameter to a computer. The computer includes a computer program which is configured to determine the radiation dose received by the item or items by correlating the value of the monitored electronic parameter to a corresponding amount of radiation associated with the value. Related sensors and systems are also described.

Abstract: An improved nuclear diagnostic method identifies a contained target material by measuring on-axis, mono-energetic uncollided particle radiation transmitted through a target material for two penetrating radiation beam energies, and applying specially developed algorithms to estimate a ratio of macroscopic neutron cross-sections for the uncollided particle radiation at the two energies, where the penetrating radiation is a neutron beam, or a ratio of linear attenuation coefficients for the uncollided particle radiation at the two energies, where the penetrating radiation is a gamma-ray beam. Alternatively, the measurements are used to derive a minimization formula based on the macroscopic neutron cross-sections for the uncollided particle radiation at the two neutron beam energies, or the linear attenuation coefficients for the uncollided particle radiation at the two gamma-ray beam energies.

Abstract: Detection of submicron scale cracks and other mechanical and chemical surface anomalies using PET. This surface technique has sufficient sensitivity to detect single voids or pits of sub-millimeter size and single cracks or fissures of millimeter size; and single cracks or fissures of millimeter-scale length, micrometer-scale depth, and nanometer-scale length, micrometer-scale depth, and nanometer-scale width. This technique can also be applied to detect surface regions of differing chemical reactivity. It may be utilized in a scanning or survey mode to simultaneously detect such mechanical or chemical features over large interior or exterior surface areas of parts as large as about 50 cm in diameter. The technique involves exposing a surface to short-lived radioactive gas for a time period, removing the excess gas to leave a partial monolayer, determining the location and shape of the cracks, voids, porous regions, etc., and calculating the width, depth, and length thereof. Detection of 0.

Abstract: There is disclosed an autoradiography system which includes an autoradiography sample, a substantially radioisotope free microchannel plate (MCP), and an MCP signal collection means, wherein the MCP directly measures beta particles from radioisotopes within the sample.

Abstract: A method of determining coincidence correction for a radiation detector in the presence of a radiation source symmetrical around the axis of the radiation detector, including: calculating the coincidence correction per the equation COI g = ϵ g ∫ ∫ ∫ ϵ ( g ) ⁢ x , y , z COI ( g )

Abstract: A radioisotope proximity sensor is provided for detecting proximity or distance to a nearby object containing a small radiation source complementary to the sensor. The output of the sensor is amplified or compared to determine the distance or proximity. The radioisotope proximity sensor is unaffected by magnetic fields over the short sensing distances. It is also unaffected by environmental contamination when the appropriate radiosource/detector combination is used. The radioisotope proximity sensor is easily shielded from electrostatic or electromagnetic noise, and the radiation source can be small, easily incorporated, and requires no external power or connections to affect mechanical reliability or impede armature movement.

Abstract: According to the present invention, a system for measuring a thermal neutron emission from a neutron source, has a reflector/moderator proximate the neutron source that reflects and moderates neutrons from the neutron source. The reflector/moderator further directs thermal neutrons toward an unmoderated thermal neutron detector.

Abstract: A microwave/dielectric-response-based security system, and a related methodology, for detecting contraband. The system (which implements the associated method) includes an interrogation region through which a target that is to be screened passes, an appropriate transmitter/receiver array that operates adjacent this region for illuminating, and monitoring a dielectric response received from, a target in the region, and electronics which effectively produce output data that is interpretable to identify the presence or absence of contraband associated with the illuminated target.

Abstract: Described are preferred devices and systems useful in the non-destructive detection of predetermined substances, such as plastique explosives, in objects under interrogation. The devices and systems are readily constructed and can be manufactured as self-contained, portable detection devices.

Abstract: An apparatus for testing air having contaminants and radon progeny therein. The apparatus includes a sampling box having an inlet for receiving the air and an outlet for discharging the air. The sampling box includes a filter made of a plate of sintered stainless steel. The filter traps the contaminants, yet allows at least a portion of the radon progeny to pass therethrough.A method of testing air having contaminants and radon progeny therein. The method includes providing a testing apparatus that has a sampling box with an inlet for receiving the air and an outlet for discharging the air, and has a sintered stainless steel filter disposed within said sampling box; drawing air from a source into the sampling box using a vacuum pump; passing the air through the filter; monitoring the contaminants trapped by the filter; and providing an alarm when a selected level of contaminants is reached. The filter traps the contaminants, yet allows at least a portion of the radon progeny to pass therethrough.

Abstract: An ultralow background multiphoton detectors device for radioisotopes has a background of about one count per day. Two opposed gamma and X-ray photon detectors each preferably include a scintillation crystal and a photomultiplier tube. Sandwiched between the detectors are a separator and a sample holder for a sample labelled with a radioisotope such as I.sup.125. The detectors convert emissions from the radioisotope into electric output pulses which are then subjected to signal processing for pulse shape analysis, discrimination of coincident from non-coincident events, and quantification of the radioisotope. Detector materials and components are selected to minimize background, and are shielded from external radiation. The device may further be constructed to resolve and provide images of two dimensional sample arrays.

Abstract: A very low profile ionization chamber provides increased operating current by using alpha particle emitting isotopes having low emission energies as an ionization source. The chamber includes a cylindrically shaped housing having height generally equal to a radius thereof. A conically shaped sensing electrode is carried within the housing. The housing is closed at one end by a main field electrode and at the other end by an insulating closure panel. A second field electrode is carried on the closure panel. The second field electrode also carries the ionization source. The conically shaped sensing electrode has an open central region which permits alpha particles to travel therethrough toward the first field electrode. The first field electrode could either exhibit a conical cross-section or could be planar. A chamber height on the order of 1.5 to 2 centimeters and a diameter in a range of 3-4 centimeters with a Gd148 source produces operating currents on the order of 10 pA.

Abstract: A patient detection system having a plurality of optical sensors associated with a corresponding plurality of file receptacles at a health care facility. The optical sensors are interfaced with one or more visual display devices. Insertion of a patient's file into a file receptacle automatically generates an output signal that activates remotely located corresponding visual indicators that notifies health care personnel that a patient is waiting.

Abstract: The invention intends to measure true distribution of a radioactive nuclide in respective parts of a subject. A density of each part of a subject sample is measured by measuring the intensity of ionizing radiation for density measurement from a radioactive nuclide for density measurement, which emits the ionizing radiation to each part of the subject sample in the same amount, through the subject sample interposed midway, the intensity of ionizing radiation emitted from another radioactive nuclide existing in each part of the subject sample is measured, and the amount of another radioactive nuclide in each part of the subject sample is determined by compensating the measured intensity of the ionizing radiation from another radioactive nuclide based on the self-absorptivity of each part of the subject sample corresponding to the density thereof.

Abstract: The instant invention relates to a method to compensate for extraneous radiation caused by the effects of intermittent active radiation sources (not effects due to cosmic or terrestrial radiation) that can cause errors in radiation measured values. For the purposes of suppressing these extraneous radiation effects in radio-active measuring methods, the commencement and termination of the extraneous radiation and the attainment of a stable condition in the extraneous radiation are determined. The difference between the measured value (before commencement of the extraneous radiation) and the measured value (on attainment of the stable condition) is determined. The measured value is then reduced by the determined difference for the duration of the extraneous radiation.

Abstract: A method and apparatus for detecting the mean atomic number of a mass of material, for example freight in a vehicle comprises: subjecting the mass to X-rays and determining the mean number N.sub.A passing therethrough; subjecting the mass to higher energy X-rays and determining the new mean number N.sub.B ; and determining the mean atomic number of the mass from look-up tables against the computed ratio N.sub.A /N.sub.B. The mass, such as a railway wagon, may be scanned by two linear accelerators arranged perpendicular to each other, detector arrays being disposed respectively opposite the accelerators, so that a three dimensional image can be built up of the mass.

Abstract: A millimeter-wave sensor for detecting and measuring effluents from processing plants either remotely or on-site includes a high frequency signal source for transmitting frequency-modulated continuous waves in the millimeter or submillimeter range with a wide sweep capability and a computer-controlled detector for detecting a plurality of species of effluents on a real time basis. A high resolution spectrum of an effluent, or effluents, is generated by a deconvolution of the measured spectra resulting in a narrowing of the line widths by 2 or 3 orders of magnitude as compared with the pressure broadened spectra detected at atmospheric pressure for improved spectral specificity and measurement sensitivity. The sensor is particularly adapted for remote monitoring such as where access is limited or sensor cost restricts multiple sensors as well as for large area monitoring under nearly all weather conditions.

Abstract: Using storage phosphor recording media, two exposures are made of a sample containing two target substances tagged with different radiative emitters, for example 32-P and 35-S. The first exposure, image 1, is of the sample directly on the phosphor screen. The second exposure, image 2, is made with the appropriate absorption material between the sample and screen. Both images are captured. By using simultaneous equations isotope contributions of each label can be determined. Quantitative assessment of the contributions of the isotopes, and hence the target substances, are made by calculating isotope efficiencies both with and without the absorption filter.

Abstract: The invention relates to a method for determining the distance of a target in difficult industrial conditions, method in which (i) one of the gamma quanta produced from a radioactive source in annihilation and traveling in opposite directions is aimed at the target and the other one at a detector, which detects it, and time measuring starts; (ii) the quantum Compton-scattered from the target is detected by the same or a separate detector, and time measuring stops; (iii) the distance of the target is calculated from the time difference between (i) and (ii). The invention also relates to a device for carrying out the method, the device comprising a radioactive source, a scintillation crystal counter/counters, a time-amplitude converter (TAC) and a pulse height analyzer (PHA).

Abstract: A temperature sensing system has a signal means which provides a signal representative of a temperature responsive luminescence, where the luminescence has a characteristic time-rate-of-decay. A means for comparison is connected to the signal means and samples the signal during two time intervals, the first interval overlapping the second. The averages of the samples are compared to provide a difference signal representative of the difference between the two measured averages. Control means coupled to the comparison means provide an output representing the temperature as a function of the time-rate-of-decay, by adjusting the overlapping intervals so that the difference signal converges to a preselected limit.

Abstract: An assembly of parts forming an angle between facing surfaces of the parts and a process for producing an assembly is described. The parts (2, 4) are provided with contact elements or pads (6, 8, 10, 12) for connection to one another by means of a relatively low melting point metallic soldering material. The surface of each of the pads is wettable by the low melting point metallic material in the molten state, while areas surrounding the pads are not wettable. The contact pads of one of the parts are covered with flat coils or wafers (10, 12) of the low melting point metallic material. The wafers have the same thickness, but different volumes. The contact pads of the other part are placed on the corresponding wafers. The wafers' thickness, volumes, and spacing are chosen so that when the wafers are heated to the molten state and form truncated spherical drops due to surface tension, the parts form between them a predetermined angle. The invention has particular application to the manufacture of mirrors.

Abstract: A device for detecting ionizing radiation emanating from a plurality of samples, said device comprising: a receptacle having a planar surface and provided with a plurality of recesses each for holding a respective sample, each said recess being open at said surface; a cover member having at least one planar electrically conductive member provided with openings, said conductive member being spaced from said receptacle and being disposed parallel to said planar surface; and a voltage source connected to place said electrically conductive member at a potential which is positive relative to the potential of said planar surface.

Abstract: A plate-shaped collimator with a plurality of through-bores for increasing locality-sensitivity during measurement of the radiation from a radioactive substance, by means of a detector disposed adjacent the collimator, wherein the collimator is provided with an insulting core having two opposed major surfaces, two electrically conductive layers each disposed on a respective collimator surface, and a source connected for applying a voltage for creating, between the conductive layers, an electrical field which acts on charged particles emanating from the radioactive substance to exert on these particles a force having a main component which is directed towards the detector in a direction substantially perpendicular to the conductive layers.

Abstract: Disclosed is an electrostatic capture type radon-measuring apparatus, which includes a supporting circular cylinder supported on a supporting table with an axis of the cylinder extending substantially vertically. A positive electrode has a curved surface extending convexly upward from the upper end of the supporting cylinder. A lower positive electrode of a truncated cone shape has open upper and lower ends and extends as narrowed downward from the upper end of the supporting cylinder. A negative electrode has an upper end thereof located in the vicinity of the lower end opening of the lower positive electrode. A solid track detector is covered with an electro-conductive thin film having .alpha. ray permeability and is mounted on the negative electrode. A cover is provided on the supporting table and encloses the supporting cylinder, upper and lower positive electrodes, negative electrode and solid track detector.

Abstract: A method of and apparatus for measuring radioactivity, which determines energy spectra of radiation rays which are detected by a radiation sensor through a collimator arranged in front of a radiation detector, calculates a spectrum index on the basis of an intensity of scattered rays and an intensity of unscattered rays among the radiation rays determined by distribution of the energy spectra, calculates a density of the object to be measured or a value relating to the density of the density of the object to be measured on the basis of the spectrum index, and meters the radioactivity of the object to be measured on the basis of the value relating to the density and the intensity of the unscattered rays by one measuring step for every cross-section of the object to be measured.

Abstract: A method is shown for measuring naturally occurring pores in a specimen material. A positron is emitted from a radioactive source and enters a material to pick up an electron to form positronium. The positronium decays very rapidly into two gamma rays. The lifetime of the positronium depends on the size of the pore it is trapped within. The larger the pore, the longer the positronium will last. By measuring the decay rate of positrons over an extended time scale in the range from 30 to 500 nsec., a near relation can be developed between positronium lifetime and pore diameter.

Abstract: A .gamma. ray emitted from a reference radioactive ray source is radiated from outside to a solid radioactive waste. The radioactive intensity of the .gamma. ray emitted from the solid radioactive waste is measured during the radiation of the .gamma. ray. The radioactive intensity to be measured is discriminated into the first radiation intensity based on the reference radioactive ray source and the second radiation intensity based on the radioactive nuclide of the solid radioactive waste. A radiation absorption coefficient of the solid radioactive waste is determined based on the first radiation intensity. The distribution of radioactivity of the solid radioactive waste is determined based on the radiation absorption coefficient and the second radiation intensity.

Abstract: A corrosion monitoring probe consisting of a housing for mounting a piece of radioactive material in a surface of a body the corrosion of which is to be measured so that the radioactive material is exposed to the same corrosive environment as the surface of the body, and means for measuring the intensity of ionizing radiation emitted by the radioactive material. The housing also contains a reference source of ionizing radiation and means for exposing a radiation detector which forms part of the means for measuring the intensity of ionizing radiation emitted by the radioactive material alternately to the radioactive material and the reference source of ionizing radiation.

Abstract: A sample 10 of a composite material, such as a graphite-epoxy composite, is exposed to radiation in three distinct energy bands emanating from sources 12, 13 and 14, respectively. Corresponding detectors 16, 17 and 18 are positioned to measure the amount of energy in each band transmitted through the sample. Weight percentages of three different constituents of the sample 10 are calculated from a relatively simple algorithm whose variables include a ratio for each of said energy bands of the amount of energy that would be detected if the sample were not present in the radiation to the amount of energy transmitted through the sample when the sample is exposed to the radiation.

Abstract: A method for detecting radiation emanating from a container comprising the steps of providing shields which define a sector from which radiation can be detected. A sample from which radiation is believed to be emanating is placed in the sector so that radiation emanating from it can strike the detector. The shielding prevents background radiation from striking the detector. Also claimed is an apparatus for detecting radiation emanating from a sample comprising first and second shields and a detector. The shields define a sector from which the detector can detect radiation. Means for supporting the sample is disposed in the sector.

Abstract: In a radiographic method, first and second collimator elements are arranged between a radiation source and an image converter. When an object is irradiated with radiation beams, the collimatar elements can be switched between first and second states. In the first state, the collimator elements pass both some of the transmitted radiation beams which are not scattered by the object and transmitted therethrough and scattered radiation beams which are scattered by the object so that a first radiation image is obtained in the form of electrical signals based on the transmitted radiation beams and the scattered radiation beams. In the second state, the collimator elements pass only some of the scattered radiation beams scattered by the object so that a second radiation image is obtained in the form of electrical signals based on only the scattered radiation beams.

Abstract: An aperture device for measuring thin films has an aperture ring, of a material and thickness that is impenetrable by the radiation from radionuclides. The ring has a passage for emitted and reflected radiation extending approximately perpendicular to said ring, and a radiation device consisting of at least one collimating radiation source holder comprising a tube of a predetermined diameter that is permeable to radiation in the forward direction and has sides and a back that are impermeable to radiation and houses a radionuclide. The forward end surface of the tube lies behind the forward end surface of the passage. The cross-section of the passage is large compared to the cross-section of the radionuclide. A partition divides the passage into at least two chambers that are open at their rearward and forward ends. The partition has partition walls that are impermeable to radiation.

Abstract: In order to determine the proportion of particles of less than a predetermined size in a fluid suspension, the fluid suspension is placed in a vessel (1) and is thoroughly mixed therein by mixing means (36,37). A sample of suspension is then withdrawn from a predetermined level within the vessel (1) by means of a sampling tube (9) and is transferred by way of a flexible tube (22) to a container (15). The particle concentration of this sample is then monitored by passing x-rays from a source (17) through the container (15) and detecting the emerging x-rays with a detector (18). The sample is then drained from the container (15). After allowing the suspension in the vessel (1) to settle for a time sufficient to enable particles of said predetermined size to sink from the surface of the suspension to said predetermined level within the vessel (1) according to Stokes' law, a further sample of suspension is withdrawn from said predetermined level and transferred to the container (15).

Abstract: An in-line assay monitor for determining the content of uranium-235 in a uranium hexafluoride gas isotopic separation system is provided which removes the necessity of complete access to the operating parameters of the system for determining the uranium-235 content. The monitor is intended for uses such as safeguard applications to assure that weapons grade uranium is not being produced in an enrichment cascade. The method and monitor for carrying out the method involve cooling of a radiation pervious chamber connected in fluid communication with the selected point in the system to withdraw a specimen and solidify the specimen in the chamber. The specimen is irradiated by means of an ionizing radiation source of energy different from that of the 185 keV gamma emissions from the uranium-235 present in the specimen. Simultaneously, the gamma emissions from the uranium-235 of the specimen and the source emissions transmitted through the sample are counted and stored in a multiple channel analyzer.

Abstract: The detector comprises at least one plate of an electrooptical material having good photoconduction properties and high absorption of X- or .gamma.-rays, preferably materials comprising bismuth oxide. The plate is placed between two electrodes connected to an electric generator through a resistor. A polarized luminous beam passes through the plate. Under the action of the radiation, the conductivity of the plate varies and produces a modification of the polarization state of the luminous beam. This modification is analysed and then detected. In this way there is obtained an indication of the radiation dose received for a given period.

Abstract: A method and apparatus for accurately locating and roughly identifying a radioactive uranium and/or transuranium isotope deposited in a wound, by monitoring alpha radiation in the edge region of the wound and at the wound surface to determine whether surface contamination is present, monitoring low-energy X-ray or gamma radiation at the wound to determine the presence of a low-energy X-ray or gamma radiation source, measuring the low-energy X-ray or gamma radiation in the wound by means of a succession of detectors having progressively increasing local resolution and progressively decreasing limitation of the detectable volume to effect coarse and then fine localization of even small isotope deposits. An isotope can be roughly identified by displaying the measuring result produced by at least one of the detectors as a pulse amplitude spectrum, and comparing the displayed result with subsequently measured spectra of predetermined isotopes.

Abstract: A process for separating gaseous isotope mixtures having the general molecular composition X.sub.n1.sup.(1) X.sub.n2.sup.(2). . . X.sub.ni.sup.(i), where a constituent X.sup.(k) can be replaced by an isotope X.sup.-(k) by irradiation with laser light.

Abstract: In computerized tomographic scanning systems it is desirable to reduce the scanning time required. Therefore, it is desirable that the radiation source/radiation detector system not be stopped and subsequently accelerated again for each absorption measurement. The present system continuously rotates and the source is continuously turned on, the output signal of each radiation detector being applied via a low-pass filter to a sample-and-hold circuit having a sampling frequency which is about twice as high as the limit frequency of the low-pass filter. Better accuracy is obtained than with known scanners having discontinuous movement or a flashing radiation source.

Abstract: A solid, annular body embedding naturally occurring radioisotopes, forms a source of radiation bordering the opening of a basin at ground level, into which water percolates from a body of precipitation in the form of snow and ice accumulated on a porous cover closing the opening. Point detectors above the opening and below the basin sense radiation emitted from the source to produce signals attenuated by the accumulated precipitation reflecting changes in density thereof. Other detectors laterally spaced from the source of radiation both inside and outside its signal range, respectively measure changes in soil density and background radiation.

Abstract: A beam profile analyzer employing sector or quadrant plates each servo controlled to outline the edge of a beam.