Abstract: A method is provided for degradation-compensated evaluation of detection signals of a sensor arrangement operating on the principle of luminescence quenching, which arrangement has a luminophore that degrades over time, an excitation radiation source, and at least one optical sensor. The luminophore radiates, in accordance with a response characteristic of the sensor arrangement, in reaction to irradiation with a predefined modulated excitation radiation and as a function of the extent of an interaction of the luminophore with a quencher substance that quenches the luminescence of the luminophore. A response radiation is detected by the at least one optical sensor. The sensor arrangement outputs a detected intensity value representing an intensity of the response radiation and a detected phase value representing a phase difference of the response radiation with respect to the modulation of the excitation radiation.

Abstract: The present invention provides a method for determining a background count rate in liquid scintillation counting. The method comprises measuring an external standard spectrum (201, 202) of a sample, determining, from the external standard spectrum, an external standard count rate within an energy window (203), determining, based on the external standard count rate within the energy window, a background reference parameter, and determining, based on the background reference parameter, the background count rate from a background reference curve (301).

Abstract: A diagnostic imaging system retrieves data (206) from a plurality of accessible data sources, the accessible data sources storing data including physiological data describing a subject to be imaged, a nature of a requested diagnostic image, image preferences of a clinician who requested the diagnostic image, and previously reconstructed images of the requested nature of the subject and/or other subjects, reconstruction parameters and/or sub-routines used to reconstruct the previously reconstructed images. The system analyzes (6, 12) the retrieved data to automatically generate reconstruction parameters and/or sub-steps specific to the nature of the requested diagnostic image, the subject, and the clinician image preferences. The system controls a display device (10, 216) to display the generated reconstruction parameters and/or sub-routines to the user for a user selection.

Abstract: A microplate reader includes multiple light projecting/receiving units, the number of the light projecting/receiving units being equal to or greater than the number of wells of the microplate, each light projecting/receiving unit including a light projecting unit and a light receiving unit that correspond to one of the wells of the microplate; a reflection member configured to reflect light having passed through samples stored in the wells from the light projecting/receiving units to the light projecting/receiving units; and a light guide part including projecting-light guide paths each configured to guide the light emitted from the light projecting unit to the sample, receiving-light guide paths each configured to guide the light reflected by the reflection member and having passed through the sample to the light receiving unit, and a surrounding member including a pigment-containing resin surrounding the projecting-light guide paths and the receiving-light guide paths.

Abstract: A sample holding device and related method designed to facilitate inexpensive and reliable testing of materials or specimens with beam diffraction and scattering techniques. The device features a sample receptacle that is made out of a polymer, cellulose, polymeric material, or cellulosic material. The flexible nature and low melting point of the sample receptacle allows for reliable sealing against the vacuum or gaseous environment used for beam diffraction or scattering analysis. The sample holding device can be considered disposable because of its low cost, eliminating the need for complex or unreliable cleaning procedures.

Abstract: Provided is a photoacoustic apparatus capable of recognizing variation in reception characteristic among a plurality of receiving elements that detect an acoustic wave in the photoacoustic apparatus, with a simple configuration unique to the photoacoustic apparatus. A photoacoustic apparatus includes a detecting unit including a plurality of receiving elements configured to detect an acoustic wave that is generated when an analyte is irradiated with light; a signal processing unit configured to acquire information about the inside of the analyte from a detected signal acquired from the detecting unit; an optical absorber configured to absorb the irradiation light; and a reception characteristic calculation unit configured to calculate reception characteristic information of the plurality of receiving elements on the basis of detected signals when the plurality of receiving elements receive an acoustic wave that is generated from the optical absorber.

Abstract: A method and an apparatus for distinguishing radionuclides are disclosed. The method comprises the steps of: receiving energy generated in one or more radioactive elements; applying energy as a weight for each channel to spectrum of the received energy; and distinguishing the one or more radioactive elements on the basis of the spectrum of the spectrum to which the weight is applied. A radioactive element having an energy value corresponding to a peak value of the spectrum of the energy to which the weight is applied, as an energy value of a Compton edge, is distinguished as the one or more radioactive elements. According to the present invention, it is possible to more accurately monitor radiation even while using a plastic scintillator, and further to improve energy resolution of a plastic scintillator.

Abstract: A radioactive gas assay system comprises a scintillation cell production assembly, a detector assembly, a computer assembly, and a scintillation cell destruction assembly. The scintillation cell production assembly is configured to produce a scintillation cell comprising a glass scintillator shell containing a volume of radioactive gas. The detector assembly is configured to receive the scintillation cell and to detect photons emitted thereby. The computer assembly is configured to receive data from the detector assembly to automatically calculate an absolute activity of the volume of radioactive gas of the scintillation cell and radiation detection efficiencies of the detector assembly. The scintillation cell destruction assembly is configured to receive the scintillation cell and to rupture the substantially non-porous glass scintillator shell to release the volume of radioactive gas. A method of assaying a radioactive gas, and a scintillation cell are also described.

Abstract: A diagnostic imaging system retrieves data (206) from a plurality of accessible data sources, the accessible data sources storing data including physiological data describing a subject to be imaged, a nature of a requested diagnostic image, image preferences of a clinician who requested the diagnostic image, and previously reconstructed images of the requested nature of the subject and/or other subjects, reconstruction parameters and/or sub-routines used to reconstruct the previously reconstructed images. The system analyzes (6, 12) the retrieved data to automatically generate reconstruction parameters and/or sub-steps specific to the nature of the requested diagnostic image, the subject, and the clinician image preferences. The system controls a display device (10, 216) to display the generated reconstruction parameters and/or sub-routines to the user for a user selection.

Abstract: Described herein are radiation detection systems and methods that provide improved discrimination between different types of radioactive events. The use of multiple discriminator settings based on pulse curve shape, rather than a single setting, is surprisingly found to improve discrimination between alpha and beta events. Results demonstrate significantly lowered % spill with minimal loss of efficiency due to the enhanced discrimination. These systems and methods are particularly important in the detection of extremely low-level alpha and beta events, and in the identification and quantification of isotopes with difficult-to-distinguish pulse shapes.

Abstract: Described herein is a chip-based apparatus for amplifying nucleic acids, a cartridge housing the apparatus, and methods of using the apparatus for amplification of nucleic acids. More specifically, this invention provides integrated semiconductor chip, manufactured with standard semiconductor manufacturing process, with on-chip circuitry to perform thermal management and optical sensing necessary for amplification of nucleic acids. The apparatus and methods embodied in this invention makes it possible to build a disease diagnosis and prognosis tool that is easy to use, portable and disposable.

Abstract: Each adapter disposed on a rack includes a pair of arms that configure an opening/closing mechanism. During rack conveyance, a guiding block is slotted between a pair of legs contained in the rack. The opening/closing mechanism being abutted against the guiding block causes the opening/closing mechanism to perform an opening/closing operation. When the state of the opening/closing mechanism is changed from closed to open, a pre-measurement sample container is passed from a sample storage unit to a lifting mechanism. Subsequent to the post-measurement sample container being returned to the sample storage unit, the state of the opening/closing mechanism is changed from open to closed.

Abstract: The present invention relates to a device and method for measuring chemiluminescence, and an object is to provide a compact and reliable device and method for measuring chemiluminescence. The device includes a vessel group, a nozzle head having a gas suctioning and discharging mechanism, one or more nozzles, which are in communication with the suctioning and discharging mechanism, and to a front end of which a dispensing tip is attachable, and a magnetic force means capable of causing a magnetic field inside the attached dispensing tip, a nozzle moving mechanism, a linkage part provided to the nozzle head, linkable to the reaction vessel and capable of forming a confined space shielded from external light, a linkage part moving mechanism capable of moving the linkage part, a photometer, a shutter, and a reagent injection flow channel capable of injecting a reagent for chemiluminescence.

Abstract: In this sample measuring device a lifting mechanism conveys a sample container from a rack to a sample measuring chamber. An inside light-shielding structure is extended over the upper surface of a base frame and the lower surface of a head, and surrounds a shaft. The inside light-shielding structure is configured from a first ring groove and a first ring protrusion. When the head is in a ground state, the upper surface of the base frame and the lower surface of the head are contacted by the action of a spring. At this time, the first ring groove and the first ring protrusion are integrated. An outside light-shielding structure is provided to the periphery of the inside light-shielding structure. A top plate contains a laminate structure which includes a lightshielding sheet and a lightreflecting plate.

Abstract: In a sample analyzing apparatus, an injector assembly injects a reagent onto a sample, and luminescent light from the sample is transmitted to a detector. The assembly may be movable toward and away from the sample. The assembly may include one or more needles that communicate with one or more reservoirs supplying reagent or other liquids. The assembly may include a light guide for communicating with the detector. A cartridge may be provided in which the assembly, one or more reservoirs, and one or more pumps are disposed. The cartridge and/or the apparatus may be configured for enabling rinsing or priming to be done outside the apparatus. The cartridge and/or the apparatus may include one or more types of sensors configured for detecting, for example, the presence of liquid or bubbles in one or more locations of the apparatus and/or the cartridge.

Abstract: An apparatus and method for testing scintillator arrays, e.g., crystal arrays for PET imaging. The apparatus includes, a two-sided tray arranged to hold scintillator arrays in either side and slide the arrays into a light-tight box having a radiation source beneath the arrays and photomultiplier tubes (PMTs) above the arrays. When arranged in the testing position with the arrays interposed between the radiation source and the PMTs, ambient light from outside the box is prevented from leaking into the box and high-voltage power is supplied to the PMTs. Otherwise, to prevent PMT damage, the high-voltage is off. The radiation source is an arrangement of sealed low-activity pieces of radioactive elements, thus minimizing requirements for radiation shielding and minimizing safety risks. The method calculates a flood map from scintillation data/counts and performs analysis according to predefined criteria, e.g., the peak-to-valley ratio, to flag arrays exhibiting inferior quality.

Abstract: An optical head for receiving incident light is provided. The optical head comprises a transmissive cosine corrector and a reflector disposed to face the transmissive cosine corrector. The transmissive cosine corrector is disposed in an optical path of the incident light and shields the reflector from the incident light. The transmissive cosine corrector converts the incident light to scattered light having a Lambertian pattern. The reflector has an optical output section that transmits the scattered light and a reflective section that reflects the scattered light to the transmissive cosine corrector and/or the other portions of the reflective sections. An optical system using the optical head is also provided.

Abstract: The present document describes an in vitro method for determining a level of mitochondrial function from a subject by determining a change in a labeled compound labeling a viable cell or tissue sample isolated from a subject following introduction of a volume of a solution over said viable cell or tissue sample. The comparison of the change to a normal reference is indicative of mitochondrial function in the subject.

Abstract: Method of determination of an irradiation dose deposited in a scintillator (5) by ionising radiation, comprising the steps of: irradiating the scintillator (5) during a predetermined time; detecting a moment of excitation of the scintillator (5) with a first photodetector (11); then detecting a moment of reception of a scintillation photon with a second photodetector (14), functioning in single photon counting mode; identifying each sequence consisting of the detection of a moment of excitation by the first photodetector (11), and the detection of a moment of reception by the second photodetector (14) with a coincidence event; counting the number of coincidence events; obtaining the irradiation dose deposited during the irradiation time as a function of the number of coincidence events counted and of a predetermined proportionality factor.

Abstract: A method for an automatic analyzer to reduce a user's workload required when a reagent is placed therein, and thereby facilitating change of the operation mode of the automatic analyzer. The automatic analyzer including a first reagent storing unit that is capable of storing a plurality of reagent cassettes and a second reagent storing unit that is capable of storing a plurality of reagent cassettes. When the first reagent storing unit does not have empty space for a required reagent, and all reagents required for analysis operation for a selected operation set cannot be completely transferred to the first reagent storing unit, keeping the required reagent waiting in the second reagent storing unit. Further, when the first reagent storing unit is provided with empty space, the required reagent is transferred to the first reagent storing unit.

Abstract: A pattern inspection apparatus can be provided, for example, in a scanning electron microscope system. When patterns of a plurality of layers are included in a SEM image, the apparatus separates the patterns according to each layer by using design data of the plurality of layers corresponding to the patterns. Consequently, the apparatus can realize inspection with use of only the pattern of a target layer to be inspected, pattern inspection differently for different layers, or detection of a positional offset between the layers.

Abstract: The present invention relates to an automatic radioactivity analyzer of mixed liquid beta emitter which comprises: a sample preparation part (1, 2, 3, 4, 5, 6, and 7) for extracting a liquid sample from liquid-phase radioactive nuclear wastes; a sample injection part (9 and 10), including a sample transportation part for transporting a bottled sample to a radioactivity detection part to perform measurement; the radioactivity detection part (11) including two photon multiplier tubes; an exterior gamma-ray source injection part (12) for compensating for measurement efficiency according to quenching effects; a signal processing part (13), including a pre-amplifier circuit (14), a high-voltage generator circuit (15), an analogue-to-digital converter circuit (21), and a digital signal processor (DSP) (24), for generating beta spectrums by the aid of a fast coincidence counter (20) and a multi-channel analyzer (22); a main control PC (25) and a graphic user interface (GUI) program (29) for remotely automatically me

Abstract: A radioactivity dose calibrator system measures the quantity of radioactive material contained in a sample-vial or syringe without removing the vial or syringe from its primary radiation shield. The system comprises a first radiation detector, a second radiation detector, a transportable, shielded radioactive material sample-holder, a signal-processing circuit and a video display.

Abstract: A system and method employing infrared laser spectrography and dual wavelength modulation to monitor the concentration of a gas, such as oxygen or carbon dioxide, in the sample vial, or to monitor the pressure in the sample vial, to thus detect for microorganism growth in the sample vial. The system and method each employ an energy emitting device, such as an infrared laser, a detector and a signal analyzer, such as a spectroscopy device. The infrared laser emits toward the container infrared energy having a substantially single wavelength substantially equal to a wavelength at which the gas absorbs the infrared energy. The detector detects a portion of the energy signal that passes through the container, and the signal analyzer spectroscopically analyzes the detected portion of the energy signal to determine whether the gas exists in the container, or to determine the pressure in the container.

Abstract: An apparatus and method for enhancing an image relayed by a central beam of collimated light centered on the optical axis of a lens with an aperture area of A and focused on the focal plane of the lens. The apparatus having an aperture at least n times as big as A centered on the optical axis of the lens to admit a collimated relay beam including the central beam and a diverter means for separating the relay beam into n collimated facet beams equal to the central beam, but exclusive thereof, and redirecting them through the lens aperture to produce n additional images on the same focal plane. The apparatus also including a processor with a separate opto-electronic device for each image that converts it between electronic and photonic states, the electronic images being stored in the processor.

Abstract: A laboratory device design particularly for a multiplate format that includes a tray having at least one well with a support associated with the well, and a removable undercover. The undercover protects the support or membrane from external contamination without causing excessive force on an individual well that can cause membrane flatness. The undercover is easily removable to provide access to the support or membrane. The undercover, when affixed to the underside of the multiwell plate or tray, allows the assembly to be transportable as a single unit while still being in compliance with SBS automation standards.

Abstract: A method and an apparatus for measuring low energy radiation from a sample provided on a sample carrier (6, 6I). The sample is positioned in a shielded cavity (8) between two oppositely aligned Geiger-Müller tubes (11, 12) such that sample radiation either reaches both of the tubes or one of the tubes, in which case the other tube is for measuring background radiation only. Both tubes are used for measuring coincidental pulses, which are disregarded. A background radiation value, to be subtracted for obtaining a sample radiation value, is determined using either a historical background radiation value or both the historical background radiation value and a background radiation value obtained during the actual sample measurement. In the case of both tubes measuring sample radiation, there can be provided a third Geiger-Müller tube (13) for measuring background radiation only.

Abstract: A method is provided for selective binding and detecting target molecules, and a method for detecting biological molecules, the method comprising supplying a semi-conductor capable of charge pair separation, and juxtaposing affinity moieties to the semi-conductor so as to effect changes in the charge pair separation characteristics when the affinity molecules are bound to the target molecules.

Abstract: A sample changer for transferring radioactive samples between a hot cell (12) and a measuring apparatus (10), as e.g. a hybrid K-edge densitometer, comprises a transfer channel (28) axially extending through a tubular containment (22) between the charging/discharging port and the measuring window section D. A recipient (24), with at least one compartment (100) for receiving therein a radioactive sample, is arranged in the transfer channel (28) so as to be movable therethrough. A threaded spindle (44) is rotatably housed in a spindle channel (42) below the transfer channel (28). A coupling (46) passing in a sealed manner through the closed rear end section connects a stepping motor (34) to the threaded spindle (44). A longitudinally guided support carriage supports the magazine (24) and engages the threaded spindle (44), so as to be subjected to a translational movement upon rotation of the spindle (44).

Abstract: A dose reading device comprises: an ultraviolet irradiating section 40 for irradiating an ultraviolet laser beam forming an excitation light source for fluorescent glass elements X; a fluorescence detecting section 50 for detecting a radiation exposure dose from the intensity of fluorescence generated by a fluorescent glass element X; a magazine conveying section 30 for conveying a magazine 10 capable of accommodating a plurality of fluorescent glass elements X to a position for measurement by the fluorescence detecting section 50; a dark box for accommodating the magazine conveying section 30 and the fluorescence detecting section 50; a first shielding plate 31c set at a non-perpendicular angle to the light axis of the ultraviolet laser beam having passed through the fluorescent glass element X; a second shielding plate 31e for shielding fluorescence from the fluorescent glass elements X other than the fluorescent glass element X under measurement; and first and second slit plates 41a, 42a for transmitting o

Abstract: A cylindrical silver-activated phosphate glass base material 2 is placed inside a heater 1. The upper end of this base material 2 is set in a supporting section 3, and an extending section 4 provided in vertically movable fashion by means of a drive device is attached to the lower end thereof. As the base material 2 is softened by the heating of the heater 1, and the extending section 4 is lowered by operating the drive device, the base material 2 is extended and assumes a thin bar shape. The extension rate of the extending section 4 driven by the drive device is controlled by an external diameter control section 5, while detecting the external diameter, in such a manner that the external diameter of the extended portion is uniform. The extended portion 6 of the base material 2 is cut to uniform lengths, and the cut faces thereof are polished by a polishing device, thereby yielding a cylindrical dosimeter glass element 7a.

Abstract: Methods and devices for stop flow detection and measurement of radioactivity in liquid samples are provided. In some embodiments, the invention includes precise positioning of fractions within a flow cell detection area. Novel flow cells and methods providing for flushing samples with gas are also provided.

Abstract: The invention relates to the field of radio-ecological monitoring, in particular to a method for measuring the content of radionuclides in components of the environment. The technical result is enhancement of the sensitivity of liquid scintillation analysis of radionuclides with low activity in the presence of radionuclides with high activity. Selection and preparation of a sample for measurements are carried out, the spectrum of the sample is measured and recorded, the measured spectrum Pi is grouped, model spectrum Mi=&Sgr;cj Mij, wherein cj designates relative contributions of base spectra of radionuclides in the model spectrum, is created on the basis of a library of base spectra of radionuclides Mij, where i is the No.

Abstract: A multiple vessel container for testing fluids comprises a gap part formed to have a width smaller than the caliber of a front end portion of a liquid sucking/discharging line. The gap part has a shape capable of aspirating and discharging all liquid through the front end portion of the line, even when the front end portion is in contact with the inside bottom of the container. The container is formed such that, upon fluid discharging, reaction between a sample and a reagent can be made uniform by discharging and diffusing aspirated liquid.

Abstract: Combinations, called matrices with memories, of matrix materials with remotely addressable or remotely programmable recording devices that contain at least one data storage unit are provided. The matrix materials are those that are used in as supports in solid phase chemical and biochemical syntheses, immunoassays and hybridization reactions. The matrix materials may additionally include fluophors or other luminescent moieties to produce luminescing matrices with memories. The data storage units are non-volatile antifuse memories or volatile memories, such as EEPROMS, DRAMS or flash memory. By virtue of this combination, molecules and biological particles, such as phage and viral particles and cells, that are in proximity or in physical contact with the matrix combination can be labeled by programming the memory with identifying information and can be identified by retrieving the stored information. Combinations of matrix materials, memories, and linked molecules and biological materials are also provided.

Abstract: A device and a method are intended for use in a spectroscopic analysis, especially performed with the aid of Raman spectroscopy, of a solid sample, such as a tablet (1). By means of a sample holder (7), the sample (1) is positioned in relation to an excitation beam which, during implementation of the analysis, falls upon a reception surface of the sample (1), the impingement area (S) being smaller than the reception surface of the sample (1). The sample holder (7) is rotated about an axis of rotation (A) parallel to the excitation beam, such that the point of impingement (S) of the excitation beam describes an annular scanning trace (20) on the reception surface of the sample (1). During implementation of the analysis, the radius of the annular scanning trace (20) is varied to enable a fairly large volume of the sample to be analysed.

Abstract: A bottle retaining mechanism holds a culture bottle in place in a cell in an incubating apparatus which agitates the culture bottle and detects the growth of microorganisms in the culture bottle. When a bottle is not present in the cell of the apparatus, the retaining mechanism moves to a position which reflects light from the light emitter to the light detector in an amount greater than the amount of light reflected off of a bottle when present, so as to indicate when a bottle is not present in a cavity of the bottle holder. The retaining mechanism/reflectance flag also is capable of providing a reference signal for auto-calibration purposes. The amount of light reflected from the retaining mechanism/reflectance flag to the light detector in a cell when no bottle is present can be monitored in order to detect changes in the cell. By monitoring such changes in the empty cell, drift from the original cell calibration can be monitored.

Abstract: Monitoring apparatus comprises a support device for receiving a plurality of items to be monitored in an array, each item having a unique machine-readable identifying reference associated therewith, the arrangement being such that the items are movable to different positions in the array; a sensor device for intermittently and repeatedly monitoring each item in the array to monitor changes in a variable associated with each item and to read the reference associated with each item; device for supplying data to the monitored variable and machine-readable reference of each item to a computer, wherein the computer relates the monitored variable to the reference to each item independently of the position of the item in the array.

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 class of polycyclic aromatic compounds containing at least two fused rings, is used to produce very bright liquid or plastic scintillators. When a member of this class, such as pyrene, is added at high concentration to a liquid or polymeric organic solvent, scintillation light output may be increased by between 40 and 100% as compared to existing commercial scintillating compositions. These new bright scintillator compositions can be used in scintillating optical fibers and plates made therefrom. These new scintillating optical fiber plates are particularly useful for diagnostic medical X-ray detection, and superior spatial resolution particle detection and measurement of high energy particles and radiation.

Abstract: A holder for samples to be analyzed in a spectrometer is made of a polymer to avoid introducing metal contaminates into the test from the usual metal holder. The preferred polymer is polyvinylidenefluoride (PDVF). The holder uses less expensive polymers for components that do not require the properties of PDVF, and it is constructed to permit replacing parts made of PDVF that have become damaged.

Abstract: A device for counting liquid scintillation samples which can count a single sample or several samples simultaneously. A transport system moves samples from a storage section to a counting section. The samples are placed on sample plate holders to assist the transport system in movement of the sample from the storage section to the counting section.

Abstract: A method for the evaluation of sample activities in multidetector liquid scintillation counters. All prepared quench curve standards are measured only in one reference detector in order to establish the relationship between the quench levels and the counting efficiencies. In addition, only two of the standards, preferably those with lowest and highest level of quench, are measured in every detector in order to establish the relationship of the quench levels between the reference detector and any other detector and in order to establish the relationship of the counting efficiencies between the reference detector and any other detector. The activities of unknown samples are evaluated by utilizing the predetermined relationships.

Abstract: A method and a liquid scintillation counter for measuring a sample, a mixture of the specimen to be analysed and a scintillator, in a liquid scintillation counter where the sample (14) is measured with two photo multiplier tubes (23, 24) situated on different sides of the sample. The photo multiplier tubes situated on different sides of the sample operate in coincidence. Asymmetric samples are measured in such a way that the counting efficiency is measured with the photo multiplier tubes (23, 24) operating in coincidence ad calculated using the amount of coincidence pulses, whereas the amplitude and the pulse height distribution are measured only with one photo multiplier tube (23 or 24).

Abstract: A method for use in liquid scintillation counting for detecting, recording and analyzing scintillation phenomena due to ionizing radiation in a device having a measuring chamber into which the sample is placed and which sample is measured with at least two light detectors. The occurrences of the measurement are recorded so completely that the measurement can be reconstructed and the analyzing principle can be decided afterwards.

Abstract: An invention for preventing optical crosstalk in a process of counting liquid scintillation samples deposited in a sample plate, the sample plate composed of a plurality of sample wells, the optical crosstalk being caused by mutual optical affection between samples deposited in the sample wells. Sample wells are provided with tubes made of material impermeable but reflective or scattering for scintillation light generated by the samples.

Abstract: A method for scintillation counting and a scintillation counter exploiting a coincidence technique, in which the coincidence resolving time is flexible and can be automatically adjusted to fit the scintillation characteristics of each sample separately. This is accomplished by measuring during a short initial period the pulse length of the scintillation pulses, and adjusting the coincidence resolving time of the coincidence analyzer before the actual counting of the sample.

Abstract: A normalization system for multi-photodetector single photon counting luminescent measuring systems and a standard for use in the same. The method comprises calculating one or more counting ratios for each photodetector in the single photon counting system and multiplying counts of unknown samples by the inverse of the appropriate counting ratio. A counting ratio for a particular photodetector is calculated by dividing the count of a standard measured by the photodetector by the count of the same standard measured by a reference photodetector. The particular standard developed employs calcium tungstate:lead as a scintillator and tritium or carbon-14 thymidine as a means of exciting the scintillator. This standard has the advantages of providing a good model of typical luminescence chemistry and producing an emission pattern which is susceptible to single photon counting.

Abstract: A method for correcting measuring values when measuring liquid scintillation samples deposited on sample plates by a photodetector which will be affected by scintillation photons from other samples in the plate in addition to the sample being measured. Said correction is done by pre-determining affection of the other samples of the plate as a function of quench level and correcting observed measuring values using this information.

Abstract: An arrangement for counting liquid scintillation samples on bottom-window multi-well sample plates in a liquid scintillation counter. The sample plates include a plurality of samples wells having light impermeable side walls and a light permeable bottom sheet which covers and forms the bottoms of said sample wells. The liquid scintillation counter includes at least one photomultiplier tube and a sample plate holder. The sample plate holder includes a device to hold sample plates of different sizes and a device to enable transporting of the sample plate holder by the scintillation counter. For preventing light passage between sample wells in the permeable bottom sheet a light permeable adhesive foil provided with black lines or other light passage preventing treatment between the sample wells is attached to the bottom side of the sample plate.