WorldWideScience
 
 
1

Method of enhancing radiation response of radiation detection materials  

Energy Technology Data Exchange (ETDEWEB)

The present invention is a method of increasing radiation response of a radiation detection material for a given radiation signal by first pressurizing the radiation detection material. Pressurization may be accomplished by any means including mechanical and/or hydraulic. In this application, the term "pressure" includes fluid pressure and/or mechanical stress.

Miller, Steven D. (Richland, WA)

1997-01-01

2

Radiation detection device and a radiation detection method  

International Nuclear Information System (INIS)

[en] A radiation detection device is described including at least one scintillator in the path of radiation emissions from a distributed radiation source; a plurality of photodetectors for viewing each scintillator; a signal processing means, a storage means, and a data processing means that are interconnected with one another and connected to said photodetectors; and display means connected to the data processing means to locate a plurality of radiation sources in said distributed radiation source and to provide an image of the distributed radiation sources. The storage means includes radiation emission response data and location data from a plurality of known locations for use by the data processing means to derive a more accurate image by comparison of radiation responses from known locations with radiation responses from unknown locations. (auth)

1975-01-01

3

Bayesian Methods for Radiation Detection and Dosimetry  

International Nuclear Information System (INIS)

We performed work in three areas: radiation detection, external and internal radiation dosimetry. In radiation detection we developed Bayesian techniques to estimate the net activity of high and low activity radioactive samples. These techniques have the advantage that the remaining uncertainty about the net activity is described by probability densities. Graphs of the densities show the uncertainty in pictorial form. Figure 1 below demonstrates this point. We applied stochastic processes for a method to obtain Bayesian estimates of 222Rn-daughter products from observed counting rates. In external radiation dosimetry we studied and developed Bayesian methods to estimate radiation doses to an individual with radiation induced chromosome aberrations. We analyzed chromosome aberrations after exposure to gammas and neutrons and developed a method for dose-estimation after criticality accidents. The research in internal radiation dosimetry focused on parameter estimation for compartmental models from observed compartmental activities. From the estimated probability densities of the model parameters we were able to derive the densities for compartmental activities for a two compartment catenary model at different times. We also calculated the average activities and their standard deviation for a simple two compartment model.

2002-01-01

4

Bayesian Methods for Radiation Detection and Dosimetry  

Energy Technology Data Exchange (ETDEWEB)

We performed work in three areas: radiation detection, external and internal radiation dosimetry. In radiation detection we developed Bayesian techniques to estimate the net activity of high and low activity radioactive samples. These techniques have the advantage that the remaining uncertainty about the net activity is described by probability densities. Graphs of the densities show the uncertainty in pictorial form. Figure 1 below demonstrates this point. We applied stochastic processes for a method to obtain Bayesian estimates of 222Rn-daughter products from observed counting rates. In external radiation dosimetry we studied and developed Bayesian methods to estimate radiation doses to an individual with radiation induced chromosome aberrations. We analyzed chromosome aberrations after exposure to gammas and neutrons and developed a method for dose-estimation after criticality accidents. The research in internal radiation dosimetry focused on parameter estimation for compartmental models from observed compartmental activities. From the estimated probability densities of the model parameters we were able to derive the densities for compartmental activities for a two compartment catenary model at different times. We also calculated the average activities and their standard deviation for a simple two compartment model.

Peter G. Groer

2002-09-29

5

Apparatus and method for detecting gamma radiation  

Energy Technology Data Exchange (ETDEWEB)

A high efficiency radiation detector for measuring X-ray and gamma radiation from small-volume, low-activity liquid samples with an overall uncertainty better than 0.7% (one sigma SD). The radiation detector includes a hyperpure germanium well detector, a collimator, and a reference source. The well detector monitors gamma radiation emitted by the reference source and a radioactive isotope or isotopes in a sample source. The radiation from the reference source is collimated to avoid attenuation of reference source gamma radiation by the sample. Signals from the well detector are processed and stored, and the stored data is analyzed to determine the radioactive isotope(s) content of the sample. Minor self-attenuation corrections are calculated from chemical composition data.

Sigg, Raymond A. (Martinez, GA)

1994-01-01

6

Method for radiation detection and measurement  

Energy Technology Data Exchange (ETDEWEB)

Dose of radiation to which a body of crystalline material has been exposed is measured by exposing the body to optical radiation at a first wavelength, which is greater than about 540 nm, and measuring optical energy emitted from the body by luminescence at a second wavelength, which is longer than the first wavelength.

Miller, Steven D. (Richland, WA)

1993-01-01

7

Method for detecting radiation dose utilizing thermoluminescent material  

Energy Technology Data Exchange (ETDEWEB)

The amount of ionizing radiation to which a thermoluminescent material has been exposed is determined by first cooling the thermoluminescent material and then optically stimulating the thermoluminescent material by exposure to light. Visible light emitted by the thermoluminescent material as it is allowed to warm up to room temperature is detected and counted. The thermoluminescent material may be annealed by exposure to ultraviolet light.

Miller, Steven D. (Richland, WA); McDonald, Joseph C. (Pasco, WA); Eichner, Fred N. (Kennewick, WA); Durham, James S. (Richland, WA)

1992-01-01

8

Apparatus and method for detecting full-capture radiation events  

Energy Technology Data Exchange (ETDEWEB)

An apparatus and method for sampling the output signal of a radiation detector and distinguishing full-capture radiation events from Compton scattering events. The output signal of a radiation detector is continuously sampled. The samples are converted to digital values and input to a discriminator where samples that are representative of events are identified. The discriminator transfers only event samples, that is, samples representing full-capture events and Compton events, to a signal processor where the samples are saved in a three-dimensional count matrix with time (from the time of onset of the pulse) on the first axis, sample pulse current amplitude on the second axis, and number of samples on the third axis. The stored data are analyzed to separate the Compton events from full-capture events, and the energy of the full-capture events is determined without having determined the energies of any of the individual radiation detector events.

Odell, Daniel M. C. (Aiken, SC)

1994-01-01

9

Method for detecting radiation dose utilizing thermoluminescent material  

Energy Technology Data Exchange (ETDEWEB)

The amount of ionizing radiation to which a thermoluminescent material has been exposed is determined by first cooling the thermoluminescent material to a cryogenic temperature. The thermoluminescent material is then optically stimulated by exposure to ultraviolet light. Visible light emitted by the thermoluminescent material as it is allowed to warm up to room temperature is detected and counted. The thermoluminescent material may be annealed by exposure to ultraviolet light.

Miller, Steven D. (Richland, WA); McDonald, Joseph C. (Pasco, WA); Eichner, Fred N. (Kennewick, WA); Tomeraasen, Paul L. (Richland, WA)

1991-01-01

10

Main Achievements 2003-2004 - Interdisciplinary Research - Radiation detection methods for health, earth and environmental sciences  

International Nuclear Information System (INIS)

[en] The IFJ research programme in this area is aimed at developing quantitative methods to monitor various environmental hazards, such as natural (including extra-terrestrial) and anthropogenic nuclear radiation, greenhouse gases emission etc. Its second task is to design and manufacture dedicated detectors of ionising radiation for radiation protection and for medical applications, and to detect environmental radiation and pollution. One of the strongest areas of project development is directed towards Earth sciences

2005-01-01

11

Method for increased sensitivity of radiation detection and measurement  

Energy Technology Data Exchange (ETDEWEB)

Dose of radiation to which a body of crystalline material has been exposed is measured by exposing the body to optical radiation at a first wavelength, which is greater than about 540 nm, and measuring optical energy emitted from the body by luminescence at a second wavelength, which is longer than the first wavelength. Reduced background is accomplished by more thorough annealing and enhanced radiation induced luminescence is obtained by treating the crystalline material to coalesce primary damage centers into secondary damage centers.

Miller, Steven D. (Richland, WA)

1994-01-01

12

Method and apparatus for providing pulse pile-up correction in charge quantizing radiation detection systems  

Energy Technology Data Exchange (ETDEWEB)

A radiation detection method and system for continuously correcting the quantization of detected charge during pulse pile-up conditions. Charge pulses from a radiation detector responsive to the energy of detected radiation events are converted to voltage pulses of predetermined shape whose peak amplitudes are proportional to the quantity of charge of each corresponding detected event by means of a charge-sensitive preamplifier. These peak amplitudes are sampled and stored sequentially in accordance with their respective times of occurrence. Based on the stored peak amplitudes and times of occurrence, a correction factor is generated which represents the fraction of a previous pulses influence on a preceding pulse peak amplitude. This correction factor is subtracted from the following pulse amplitude in a summing amplifier whose output then represents the corrected charge quantity measurement.

Britton, Jr., Charles L. (Alcoa, TN); Wintenberg, Alan L. (Knoxville, TN)

1993-01-01

13

Radiation detection  

International Nuclear Information System (INIS)

[en] In this chapter the most common types of radiation detectors are described and reviewed. Geiger counters, scintillation counters and pulse processing equipment are described in more detail. (U.K.)

1986-01-01

14

Apparatus and method for the simultaneous detection of neutrons and ionizing electromagnetic radiation  

Energy Technology Data Exchange (ETDEWEB)

A sensor for simultaneously detecting neutrons and ionizing electromagnetic radiation comprising: a sensor for the detection of gamma radiation, the sensor defining a sensing head; the sensor further defining an output end in communication with the sensing head; and an exterior neutron-sensitive material configured to form around the sensing head; wherein the neutron-sensitive material, subsequent to the capture of the neutron, fissions into an alpha-particle and a .sup.7 Li ion that is in a first excited state in a majority of the fissions, the first excited state decaying via the emission of a single gamma ray at 478 keV which can in turn be detected by the sensing head; and wherein the sensing head can also detect the ionizing electromagnetic radiation from an incident radiation field without significant interference from the neutron-sensitive material. A method for simultaneously detecting neutrons and ionizing electromagnetic radiation comprising the steps of: providing a gamma ray sensitive detector comprising a sensing head and an output end; conforming an exterior neutron-sensitive material configured to form around the sensing head of the detector; capturing neutrons by the sensing head causing the neutron-sensitive material to fission into an alpha-particle and a .sup.7 Li ion that is in a first excited state in a majority of the fissions, the state decaying via the emission of a single gamma ray at 478 keV; sensing gamma rays entering the detector through the neutron-sensitive material; and producing an output through a readout device coupled to the output end; wherein the detector provides an output which is proportional to the energy of the absorbed ionizing electromagnetic radiation.

Bell, Zane W. (Oak Ridge, TN)

2000-01-01

15

Apparatus and method for the simultaneous detection of neutrons and ionizing electromagnetic radiation  

Energy Technology Data Exchange (ETDEWEB)

A sensor is disclosed for simultaneously detecting neutrons and ionizing electromagnetic radiation comprising: a sensor for the detection of gamma radiation, the sensor defining a sensing head; the sensor further defining an output end in communication with the sensing head; and an exterior neutron-sensitive material configured to form around the sensing head; wherein the neutron-sensitive material, subsequent to the capture of the neutron, fissions into an alpha-particle and a {sup 7}Li ion that is in a first excited state in a majority of the fissions, the first excited state decaying via the emission of a single gamma ray at 478 keV which can in turn be detected by the sensing head; and wherein the sensing head can also detect the ionizing electromagnetic radiation from an incident radiation field without significant interference from the neutron-sensitive material. A method for simultaneously detecting neutrons and ionizing electromagnetic radiation comprising the steps of: providing a gamma ray sensitive detector comprising a sensing head and an output end; conforming an exterior neutron-sensitive material configured to form around the sensing head of the detector; capturing neutrons by the sensing head causing the neutron-sensitive material to fission into an alpha-particle and a {sup 7}Li ion that is in a first excited state in a majority of the fissions, the state decaying via the emission of a single gamma ray at 478 keV; sensing gamma rays entering the detector through the neutron-sensitive material; and producing an output through a readout device coupled to the output end; wherein the detector provides an output which is proportional to the energy of the absorbed ionizing electromagnetic radiation.

Bell, Z.W.

2000-01-04

16

Apparatus and method for detecting electromagnetic radiation using electron photoemission in a micromechanical sensor  

Energy Technology Data Exchange (ETDEWEB)

A micromechanical sensor and method for detecting electromagnetic radiation involve producing photoelectrons from a metal surface in contact with a semiconductor. The photoelectrons are extracted into the semiconductor, which causes photo-induced bending. The resulting bending is measured, and a signal corresponding to the measured bending is generated and processed. A plurality of individual micromechanical sensors can be arranged in a two-dimensional matrix for imaging applications.

Datskos, Panagiotis G. (Knoxville, TN); Rajic, Slobodan (Knoxville, TN); Datskou, Irene C. (Knoxville, TN); Egert, Charles M. (Oak Ridge, TN)

2002-01-01

17

Method of detection of transition radiation by wire chambers operating in self-quenching streamer mode  

International Nuclear Information System (INIS)

[en] A method for detecting X-ray transition radiation against the background of the signal from relativistic charged particles is suggested that is based on the use of peculiarities of the development of self-queenching streamer mode. The self-qunching streamer discharge in the Xe+ isobutane mixture is experimentally registered. The effect of separation of signals from the relativistic particle and from soft X-ray, is obtained

1984-01-01

18

PTTL method applied to UV radiation detection during refractive surgery using excimer laser  

International Nuclear Information System (INIS)

The method of photo-transferred thermoluminescence (PTTL), using CaSO4:Dy pellets produced at IPEN as sensitive material, was used to detect the spread laser radiation inside the surgery room during refractive surgical procedures using ArF excimer lasers. The purpose of this work was to study the viability of performing the ultraviolet radiation (UVR) exposure detection of patients and the hospital's surgical staff during a refractive surgery. The CaSO4:Dy pellets were positioned at different distances from the laser source inside the surgery room: patient's (?0.15 m), surgeon's (?0.5 m) and nurse's (?1.0 m) foreheads, lateral (?1.5 m) and back (?4.0 m) walls. The measurements of PTTL were carried out at two different conditions: five surgeries, each one taking ?10 min, and during a period of 4 h (cumulative), when several operations were performed. The detectors positioned as far as 4.0 m from the UV laser source were sensitised, making the UVR detection feasible at large source-detector distances. The absorbed energy was detected in the range from 40 ?J to 30 mJ during a surgery. This result indicates that the method studied can be used to detect the spread UVR. (authors)

2005-01-01

19

Method of shaping of direction-characterization of sensitivity of ionizing radiation detection probe  

International Nuclear Information System (INIS)

A method of shaping of direction-characterization of sensitivity of the ionizing radiation detection probe, especially equipped with small gamma detectors is described. Two detectors are placed coaxially in the bases of the cylindrical shield. One of them is uncovered in the highest degree and the second is not covered to a maximum. The signals from them are processed on the standarized sequences of electrical impulses (taking into account the heights and the widths of the amplitude). 2 figs., 1 tab. (A.S.).

1979-12-31

20

Evaluation of phase sensitive detection method and Si avalanche photodiode for radiation thermometry  

Science.gov (United States)

We report the evaluation of Si avalanche photodiodes (APDs) for use in radiation thermometry as an alternative to Si photodiodes. We compared their performance when operated under phase sensitive detection (PSD), where the signal is modulated, and direct detection (DD) methods. A Si APD was compared with a Si photodiode with reference black body temperatures of 275 to 600°C, in terms of the mean output voltage and signal-to-noise ratio (SNR), measured at different APD gain values. We found that using both PSD and DD methods, the high internal gain of the Si APD achieved a lower minimum detection temperature in order to satisfy a specific minimum output voltage of the detector-preamplifier combination employed. The use of PSD over DD for the Si APD allowed for improved performance of the thermometer, with a lower minimum measurable temperature, as well as improvement in the SNR. For instance we found that at 350°C, the Si APD biased at 150 V using PSD can provide ~ 88 times enhancement in the system SNR over that of a Si photodiode using DD. A corresponding temperature error of ±0.05°C was achieved using the APD with PSD compared to an error of ±2.75°C measured using the Si photodiode with DD.

Hobbs, M. J.; Tan, C. H.; Willmott, J. R.

2013-03-01

 
 
 
 
21

Counterbalanced radiation detection device  

International Nuclear Information System (INIS)

[en] A counterbalanced radiation detection device is described which consists of: (a) a base; (b) a radiation detector having a known weight; (c) means connected with the radiation detector and the base for positioning the radiation detector in different heights with respect to the base; (d) electronic component means movably mounted on the base for counterbalancing the weight of the radiation detector; (e) means connected with the electronic component means and the radiation detector positioning means for positioning the electronic component means in different heights with respect to the base opposite to the heights of the radiation detector; (f) means connected with the radiation detector and the base for shifting the radiation detector horizontally with respect to the base; and (g) means connected with the electronic component means and the radiation detector shifting means for shifting the electronic component means horizontally with respect to the base in opposite direction to shifting of the radiation detector

1986-01-01

22

Semiconductor radiation detection systems  

CERN Document Server

Covers research in semiconductor detector and integrated circuit design in the context of medical imaging using ionizing radiation. This book explores other applications of semiconductor radiation detection systems in security applications such as luggage scanning, dirty bomb detection and border control.

2010-01-01

23

Apparatus and method for examining a blood vessel of interest using radiation detected outside the body  

International Nuclear Information System (INIS)

[en] A gamma camera is described in detail for use in examining the blood circulation in vessels adjacent to the heart. The radiation source (e.g. 68Ga) emits positrons whose annihilation is localised and produces two 0.115 MeV gamma rays in exactly opposite directions. By detecting both gamma rays in coincidence in position sensitive multi-wire proportional chambers, lines may be drawn between detected pairs and the intersection of of all such pairs will define the position of the positron emitting source. The radiation source may be tracked in three dimensions by suitably arranging the detectors around the patient's chest. The position of the radiation source can be recorded as a function of time and hence provide information about the velocity of blood flow through each coronary artery. This information may help determine the extent, severity and location of stenotic lesions of the coronary arteries. (U.K.)

1980-01-01

24

Comparative study on 4 quantitative detection methods of apoptosis induced by radiation  

International Nuclear Information System (INIS)

Objective: To reveal the capability of 4 apoptosis-detecting methods to discriminate between apoptosis and necrosis and show their respective advantages and shortcomings through comparison of detected results and analysis of detection mechanism. Methods: Four methods, PI staining-flow cytometric detection (P-F method), TUNEL labeling-flow cytometric detection (T-F method), annexing V-FITC/PI vital staining-flow cytometric detection (A-F method) and Hoechst/PI vital staining-fluorescence microscopic observation (H-O method), were used to determine apoptosis and necrosis in human breast cancer MCF-7 cell line induced by ?-rays. Hydroxycamptothecine and sodium azide were used to induce positive controls of apoptosis and necrosis respectively. Results: All 4 methods showed good time-dependent and dose dependent respondence to apoptosis induced by ?-rays and hydroxycamptothecine. Apoptotic cell ratios and curve slopes obtained from P-F method were minimum and, on the contrary, those from T-F method were maximum among these 4 methods. With A-F method and H-O method, two sets of data, apoptosis and necrosis, could be gained respectively and the data gained from these two methods were close to equal. A-F method and H-O method could distinguish necrosis induced by sodium azide from apoptosis while P-F method and T-F method presented false increase of apoptosis. Conclusions: P-F method and T-F method can not discriminate between apoptosis and necrosis. P-F method is less sensitive but more simple, convenient and economical than T-F method. A-F method and H-O method can distinguish necrosis from apoptosis. A-F method is more costly but more quick and reliable than H-O method. H-O method is economical, practical and morphological changes of cells and nucleus can be observed simultaneously with it. (authors)

2004-01-01

25

Radiation detection system  

Energy Technology Data Exchange (ETDEWEB)

A radiation detection system including a radiation-to-light converter and fiber optic wave guides to transmit the light to a remote location for processing. The system utilizes fluors particularly developed for use with optical fibers emitting at wavelengths greater than about 500 nm and having decay times less than about 10 ns.

Franks, Larry A. (Santa Barbara, CA); Lutz, Stephen S. (Santa Barbara, CA); Lyons, Peter B. (Los Alamos, NM)

1981-01-01

26

Development of techniques using DNA analysis method for detection/analysis of radiation-induced mutation. Development of an useful probe/primer and improvement of detection efficacy  

International Nuclear Information System (INIS)

[en] Previously, it was demonstrated that detection of centromere became easy and reliable through fluorescent staining by FISH method using a probe of the sequence preserved in ?-satelite DNA. Since it was, however, found inappropriate to detect dicentrics based on the relative amount of DNA probe on each chromosome. A prove which allows homogeneous detection of ?-satelite DNA for each chromosome was constructed. A presumed sequence specific to kinetochore, CENP-B box was amplified by PCR method and the product DNA was used as a probe. However, the variation in amounts of probe DNA among chromosomes was decreased by only about 20%. Then, a program for image processing of the results obtained from FISH using ?-satelite DNA was constructed to use as a marker for centromere. When compared with detection of abnormal chromosomes stained by the conventional method, calculation efficacy for only detection of centromere was improved by the use of this program. Calculation to discriminate the normal or not was still complicated and the detection efficacy was little improved. Chromosomal abnormalities in lymphocytes were used to detect the effects of radiation. In this method, it is needed to shift the phase of cells into metaphase. The mutation induced by radiation might be often repaired during shifting. To exclude this possibility, DNA extraction was conducted at a low temperature and immediately after exposure to 137Cs, and a rapid genome detection method was established using the genome DNA. As the model genomes, the following three were used: 1) long chain repeated sequences widely dispersed over chromosome, 2) cluster genes, 3) single copy genes. The effects of radiation were detectable at 1-2 Gy for the long repeated sequences and at 7 Gy for the cluster genes, respectively, whereas no significant effects were observed at any Gy tested for the single copy genes. Amplification was marked in the cells exposed at 1-10 Gy (peak at 4 Gy), suggesting that these regions had very highly ordered structures. (M.N.)

1999-01-01

27

Data derandomizer and method of operation for radiation imaging detection systems  

International Nuclear Information System (INIS)

[en] A radiation imaging detection system, such as a scintillation camera system, including analog data derandomizing circuitry for reducing otherwise occurring data losses is described. The derandomizing circuitry includes a peak detector, a ratio circuit, and a sample and hold circuit in combination such that a randomly occurring data pulse stored in the peak detector is transferred to the sample and hold circuit only if it is not busy. The sample and hold circuit maintains the data for a sufficient time to enable display. If the sample and hold circuit is busy and cannot accept new data for display, the peak detector stores the data pulse. The derandomizer detects only a middle portion of an incoming data pulse to determine its peak to thereby realize a timing advantage. The novel peak detector herein disclosed provides an input voltage pedestal to the input pulses for enhancing detection, and provides a dumping circuit to rapidly discharge the holding capacity at a rate proportional to the detector output voltage

1974-06-11

28

Including shielding effects in application of the TPCA method for detection of embedded radiation sources.  

Energy Technology Data Exchange (ETDEWEB)

Conventional full spectrum gamma spectroscopic analysis has the objective of quantitative identification of all the radionuclides present in a measurement. For low-energy resolution detectors such as NaI, when photopeaks alone are not sufficient for complete isotopic identification, such analysis requires template spectra for all the radionuclides present in the measurement. When many radionuclides are present it is difficult to make the correct identification and this process often requires many attempts to obtain a statistically valid solution by highly skilled spectroscopists. A previous report investigated using the targeted principal component analysis method (TPCA) for detection of embedded sources for RPM applications. This method uses spatial/temporal information from multiple spectral measurements to test the hypothesis of the presence of a target spectrum of interest in these measurements without the need to identify all the other radionuclides present. The previous analysis showed that the TPCA method has significant potential for automated detection of target radionuclides of interest, but did not include the effects of shielding. This report complements the previous analysis by including the effects of spectral distortion due to shielding effects for the same problem of detection of embedded sources. Two examples, one with one target radionuclide and the other with two, show that the TPCA method can successfully detect shielded targets in the presence of many other radionuclides. The shielding parameters are determined as part of the optimization process using interpolation of library spectra that are defined on a 2D grid of atomic numbers and areal densities.

Johnson, William C.; Shokair, Isaac R.

2011-12-01

29

Examination of stochastic methods for determination of detection limits of nuclear radiation measuring techniques  

International Nuclear Information System (INIS)

[en] The empirical study examined by means of statistical approximation tests to what extent the Poisson distribution law or the negative binomial distribution, the normal or the logarithmic normal distribution can suitably interpret nuclear radiation measurements. Whereas the data obtained by counting radiation measurement without sample preparation in general did not reject the hypothesis of Poisson's distribution governing the processes, measurements using prepared, and particularly intensively prepared, samples as a rule did not confirm applicability of this approach, but rather indicated applicability of the hypothesis of a negative binomial distribution. The study presents formulae for the calculation of detection limits and identification limits on the basis of assuming a negative binomial distribution. (orig./DG)[de] Es wurde mit Hilfe von statistischen Anpassungstests empirisch untersucht, inwieweit die Poissonverteilung und die negative Binomialverteilung, sowie die Normal- und die logarithmische Normalverteilung bei der Beschreibung von Kernstrahlungsmessungen herangezogen werden koennen. Waehrend bei zaehlenden Kernstrahlungsmessungen ohne Probenbehandlung i. allg. die Hypothese der Poissonverteilung nicht verworfen werden konnte, war dies in der Regel vor allem bei Messungen mit aufwendiger Probenbehandlung nicht der Fall. Vielfach konnte in diesen Faellen die Hypothese der negativen Binomialverteilung nicht verworfen werden. Fuer zugrundeliegende negative Binomialverteilung wurden Formeln zur Berechnung von Nachweis- und Erkennungsgrenzen vorgestellt. (orig./DG)

1989-01-01

30

Radiation detection system for embarkations  

International Nuclear Information System (INIS)

A nuclear radiation detection system is developed in order to use in frigate for continuous monitoring of ambient (water and air) radiation levels. The detection assembly consists of plastic scintillation detector and ionization chamber. (author)

1999-09-03

31

Development of techniques using DNA analysis method for detection/analysis of radiation-induced mutation. Development of an useful probe/primer and improvement of detection efficacy  

Energy Technology Data Exchange (ETDEWEB)

Previously, it was demonstrated that detection of centromere became easy and reliable through fluorescent staining by FISH method using a probe of the sequence preserved in {alpha}-satelite DNA. Since it was, however, found inappropriate to detect dicentrics based on the relative amount of DNA probe on each chromosome. A prove which allows homogeneous detection of {alpha}-satelite DNA for each chromosome was constructed. A presumed sequence specific to kinetochore, CENP-B box was amplified by PCR method and the product DNA was used as a probe. However, the variation in amounts of probe DNA among chromosomes was decreased by only about 20%. Then, a program for image processing of the results obtained from FISH using {alpha}-satelite DNA was constructed to use as a marker for centromere. When compared with detection of abnormal chromosomes stained by the conventional method, calculation efficacy for only detection of centromere was improved by the use of this program. Calculation to discriminate the normal or not was still complicated and the detection efficacy was little improved. Chromosomal abnormalities in lymphocytes were used to detect the effects of radiation. In this method, it is needed to shift the phase of cells into metaphase. The mutation induced by radiation might be often repaired during shifting. To exclude this possibility, DNA extraction was conducted at a low temperature and immediately after exposure to {sup 137}Cs, and a rapid genome detection method was established using the genome DNA. As the model genomes, the following three were used: (1) long chain repeated sequences widely dispersed over chromosome, (2) cluster genes, (3) single copy genes. The effects of radiation were detectable at 1-2 Gy for the long repeated sequences and at 7 Gy for the cluster genes, respectively, whereas no significant effects were observed at any Gy tested for the single copy genes. Amplification was marked in the cells exposed at 1-10 Gy (peak at 4 Gy), suggesting that these regions had very highly ordered structures. (M.N.)

Maekawa, Hideaki; Tsuchida, Kozo; Hashido, Kazuo; Takada, Naoko; Kameoka, Yosuke; Hirata, Makoto [National Inst. of Infectious Diseases, Tokyo (Japan)

1999-02-01

32

Radiation detection system  

International Nuclear Information System (INIS)

A circuit is disclosed that detects radiation transients and provides a clamping signal in response to each transient. The clamping signal is present from the time the transient rises above a given threshold level and for a known duration thereafter. The system includes radiation sensors, a blocking oscillator that generates a pulse in response to each sensor signal, and an output pulse duration control circuit. The oscillator pulses are fed simultaneously to the output pulse duration control circuit and to an OR gate, the output of which comprises the system output. The output pulse duration is controlled by the time required to magnetize a magnetic core to saturation in first one direction and then the other

1976-01-01

33

Radiation protection, measurements and methods  

International Nuclear Information System (INIS)

The introductory lectures discuss subjects such as radiation protection principles and appropriate measuring techniques; methods, quantities and units in radiation protection measurement; technical equipment; national and international radiation protection standards. The papers presented at the various sessions deal with: Dosimetry of external radiation (27 papers); Working environment monitoring and emission monitoring (21 contributions); Environmental monitoring (19 papers); Incorporation monitoring (9 papers); Detection limits (4 papers); Non-ionizing radiation, measurement of body dose and biological dosimetry (10 papers). All 94 contributions (lectures, compacts and posters) are retrievable as separate records. (HP)

1983-01-01

34

Radiation Detection from Fission  

Energy Technology Data Exchange (ETDEWEB)

This report briefly describes the neutrons and gamma rays emitted in fission, briefly discusses measurement methods, briefly discusses sources and detectors relevant to detection of shielded HEU in sealand containers, and lists the measurement possibilities for the various sources. The brief descriptions are supplemented by reference.

Mihalczo, J.

2004-11-17

35

Method for detecting water equivalent of snow using secondary cosmic gamma radiation  

Energy Technology Data Exchange (ETDEWEB)

Water equivalent of accumulated snow determination by measurement of secondary background cosmic radiation attenuation by the snowpack. By measuring the attentuation of 3-10 MeV secondary gamma radiation it is possible to determine the water equivalent of snowpack. The apparatus is designed to operate remotely to determine the water equivalent of snow in areas which are difficult or hazardous to access during winter, accumulate the data as a function of time and transmit, by means of an associated telemetry system, the accumulated data back to a central data collection point for analysis. The electronic circuitry is designed so that a battery pack can be used to supply power.

Condreva, Kenneth J. (1420 Fifth St., Livermore, Alameda County, CA 94550)

1997-01-01

36

Radiation Detection Computational Benchmark Scenarios  

Energy Technology Data Exchange (ETDEWEB)

Modeling forms an important component of radiation detection development, allowing for testing of new detector designs, evaluation of existing equipment against a wide variety of potential threat sources, and assessing operation performance of radiation detection systems. This can, however, result in large and complex scenarios which are time consuming to model. A variety of approaches to radiation transport modeling exist with complementary strengths and weaknesses for different problems. This variety of approaches, and the development of promising new tools (such as ORNL’s ADVANTG) which combine benefits of multiple approaches, illustrates the need for a means of evaluating or comparing different techniques for radiation detection problems. This report presents a set of 9 benchmark problems for comparing different types of radiation transport calculations, identifying appropriate tools for classes of problems, and testing and guiding the development of new methods. The benchmarks were drawn primarily from existing or previous calculations with a preference for scenarios which include experimental data, or otherwise have results with a high level of confidence, are non-sensitive, and represent problem sets of interest to NA-22. From a technical perspective, the benchmarks were chosen to span a range of difficulty and to include gamma transport, neutron transport, or both and represent different important physical processes and a range of sensitivity to angular or energy fidelity. Following benchmark identification, existing information about geometry, measurements, and previous calculations were assembled. Monte Carlo results (MCNP decks) were reviewed or created and re-run in order to attain accurate computational times and to verify agreement with experimental data, when present. Benchmark information was then conveyed to ORNL in order to guide testing and development of hybrid calculations. The results of those ADVANTG calculations were then sent to PNNL for compilation. This is a report describing the details of the selected Benchmarks and results from various transport codes.

Shaver, Mark W.; Casella, Andrew M.; Wittman, Richard S.; McDonald, Ben S.

2013-09-24

37

Principles of radiation detection  

International Nuclear Information System (INIS)

After a short description of the ionizing radiations and their interactions with matter, the properties and functions of radiation detector systems in general and of the scintillation and semiconductor detectors in particular are presented. Figs and tabs.

1988-01-01

38

Measurement and detection of radiation  

CERN Document Server

This is an update of the standard textbook for the field of radiation measurement. It includes illustrative examples and new problems. The research and applications of nuclear instrumentation have grown substantially since publication of the previous editions. With the miniaturization of equipment, increased speed of electronic components, and more sophisticated software, radiation detection systems are now more productively used in many disciplines, including nuclear nonproliferation, homeland security, and nuclear medicine. Continuing in the tradition of its bestselling predecessors, "Measurement and Detection of Radiation, Third Edition" illustrates the fundamentals of nuclear interactions and radiation detection with a multitude of examples and problems. It offers a clearly written, accessible introduction to nuclear instrumentation concepts. The following are new to the third edition: a new chapter on the latest applications of radiation detection, covering nuclear medicine, dosimetry, health physics, no...

Tsoulfanidis, Nicholas

2011-01-01

39

Apparatus and method for examining a blood vessel of interest using radiation detected outside the body  

International Nuclear Information System (INIS)

[en] Stenotic atherosclerotic lesions of the coronary arteries are detected by injecting a number of particulate signal sources such as positron-emitting particles (e.g. gallium 68) into the blood of a subject to determine the velocity of blood flow through the coronary vessels. The particles are tracked in three dimensions whenever they appear in the region of the heart by means of high-resolution high-speed gamma detectors that surround the chest. These recordings of particle position as a function of time are analyzed, and the velocity of blood as it flows through the coronary artery is measured by timing the transit of the particle. From the accumulated data of multiple particle transits through the coronary circulation, a three-dimensional representation of the lumen of the coronary arterial system is constructed

1982-01-01

40

Detection methods for irradiated food  

International Nuclear Information System (INIS)

The plenary lecture gives a brief historical review of the development of methods for the detection of food irradiation and defines the demands on such methods. The methods described in detail are as follows: 1) Physical methods: As examples of luminescence methods, thermoluminescence and chermoluminescence are mentioned; ESR spectroscopy is discussed in detail by means of individual examples (crustaceans, frutis and vegetables, spieces and herbs, nuts). 2) Chemical methods: Examples given for these are methods that make use of alterations in lipids through radiation (formation of long-chain hydrocarbons, formation of 2-alkyl butanones), respectively radiation-induced alterations in the DNA. 3) Microbiological methods. An extensive bibliography is appended. (VHE).

1993-01-01

 
 
 
 
41

Radiation detecting device  

International Nuclear Information System (INIS)

A multiwavelength radiation detector having the ability to integrate received radiation is described. The detector comprises a modified MOS field effect transistor wherein the gate takes the form of a cantilevered member formed from two layers of material of differing coefficients of expansion, one above the other. The free end of the cantilevered member extends over the space between the source and drain regions of the field effect transistor. As radiation impinges upon the cantilevered member, it will bend, causing the distance between the gate and the underlying semiconductive substrate to vary. In this manner, and assuming a constant gate voltage, the surface conductivity of the substrate between the source and drain regions can be made to vary as function of the integrated value of rediation which has impinged on the cantilevered member over a selected time interval. Such detectors can be connected in arrays, such that a radiation pattern over an area can be determined. (auth)

1975-01-01

42

Aerial Radiation Detection  

Energy Technology Data Exchange (ETDEWEB)

An airborne system designed for the detection of radioactive sources on the soil surface from an aircraft normally senses gamma rays emitted by the source. Gamma rays have the longest path length (least attenuation) through the air of any of the common radioactive emissions and will thus permit source detection at large distances. A secondary benefit from gamma rays detection if that nearly all radioactive isotopes can be identified by the spectrum of gammas emitted. Major gaseous emissions from fuel processing plants emit gammas that may be detected and identified. Some types of special nuclear material also emit neutrons which are also useful for detection at a distance.

W. M. Quam

1999-09-30

43

Aerial Radiation Detection  

International Nuclear Information System (INIS)

An airborne system designed for the detection of radioactive sources on the soil surface from an aircraft normally senses gamma rays emitted by the source. Gamma rays have the longest path length (least attenuation) through the air of any of the common radioactive emissions and will thus permit source detection at large distances. A secondary benefit from gamma rays detection if that nearly all radioactive isotopes can be identified by the spectrum of gammas emitted. Major gaseous emissions from fuel processing plants emit gammas that may be detected and identified. Some types of special nuclear material also emit neutrons which are also useful for detection at a distance

1999-01-01

44

Detection of contraband using microwave radiation  

Energy Technology Data Exchange (ETDEWEB)

The present invention relates to a method and system for using microwave radiation to detect contraband hidden inside of a non-metallic container, such as a pneumatic vehicle tire. The method relies on the attenuation, retardation, time delay, or phase shift of microwave radiation as it passes through the container plus the contraband. The method is non-invasive, non-destructive, low power, and does not require physical contact with the container.

Toth, Richard P. (Albuquerque, NM); Loubriel, Guillermo M. (Albuquerque, NM); Bacon, Larry D. (Albuquerque, NM); Watson, Robert D. (Tijeras, NM)

2002-01-01

45

Detection of nuclear radiations  

International Nuclear Information System (INIS)

A summary of the lectures about the ordinary detectors of nuclear radiations given by the author in the Courses of Introduction to Nuclear Engineering held at the JEN up to the date of publication is given. Those lectures are considered to be a necessary introduction to Nuclear Instrumentation and Applied electronics to Nuclear Engineering so it has been intent to underline those characteristics of radiation detectors that must be taken in consideration in choosing or designing the electronic equipment associated to them in order to take advantage of each detector possibilities. (Author) 8 refs.

1959-01-01

46

Methods for routine control of irradiated food: optimization of a method for detection of radiation-induced hydrocarbons and its application to various foods  

International Nuclear Information System (INIS)

By comparison of two methods for the isolation of radiation-induced hydrocarbons, high vacuum ''cold finger'' distillation and Florisil column chromatography, it could be shown that the sensitivity of both was similar whereas the latter seemed to be more practical for routine application. In optimizing studies, the influence of the degree of Florisil activation and the influence of the irradiation temperature on hydrocarbon yields as the resolution of hydrocarbons on polar and non-polar gas chromatographic capillary columns have been examined. From the successful application of the method to different fat containing foodstuffs, it is concluded that the Florisil column chromatography is well suited as clean-up procedure for the gas chromatographic/mass spectrometric (GC/MS) detection of irradiated products by routine food control analyses. (author).

1994-01-01

47

Methods for routine control of irradiated food: optimization of a method for detection of radiation-induced hydrocarbons and its application to various foods  

Energy Technology Data Exchange (ETDEWEB)

By comparison of two methods for the isolation of radiation-induced hydrocarbons, high vacuum ``cold finger`` distillation and Florisil column chromatography, it could be shown that the sensitivity of both was similar whereas the latter seemed to be more practical for routine application. In optimizing studies, the influence of the degree of Florisil activation and the influence of the irradiation temperature on hydrocarbon yields as the resolution of hydrocarbons on polar and non-polar gas chromatographic capillary columns have been examined. From the successful application of the method to different fat containing foodstuffs, it is concluded that the Florisil column chromatography is well suited as clean-up procedure for the gas chromatographic/mass spectrometric (GC/MS) detection of irradiated products by routine food control analyses. (author).

Spiegelberg, A.; Schulzki, G.; Helle, N.; Boegl, K.W.; Schrieber, G.A. [Federal Health Office, Berlin (Germany). Institute for Social Medicine and Epidemiology

1994-05-01

48

Detection of gravitational radiation  

International Nuclear Information System (INIS)

In this report the main contributions presented at the named symposium are collected. These concern astrophysical sources of gravitational radiation, ultracryogenic gravitational wave experiments, read out and data analysis of gravitational wave antennas, cryogenic aspects of large mass cooling to mK temperatures, and metallurgical and engineering aspects of large Cu structure manufacturing. (HSI).

1994-05-24

49

Methods of attenuating internal radiation exposure  

UK PubMed Central (United Kingdom)

Various radiation-attenuating agents can be administered within a patient body cavity in combination with therapeutic irradiation of the patient body cavity, such as during radiographic diagnostic imaging procedures, to attenuate the radiation incident on certain portions of the patient body cavity believed to be susceptible to harm from the incident radiation. A variety of methods are provided, including methods for detecting clinical conditions such as pulmonary embolus in a pregnant woman while mitigating uterine radiation exposure.

YOUSEFZADEH DAVID K; WARD MATTHEW; REFT CHESTER; PELIZZARI CHARLES

50

Radiation Detection for Homeland Security Applications  

Science.gov (United States)

In the past twenty years or so, there have been significant changes in the strategy and applications for homeland security. Recently there have been significant at deterring and interdicting terrorists and associated organizations. This is a shift in the normal paradigm of deterrence and surveillance of a nation and the `conventional' methods of warfare to the `unconventional' means that terrorist organizations resort to. With that shift comes the responsibility to monitor international borders for weapons of mass destruction, including radiological weapons. As a result, countries around the world are deploying radiation detection instrumentation to interdict the illegal shipment of radioactive material crossing international borders. These efforts include deployments at land, rail, air, and sea ports of entry in the US and in European and Asian countries. Radioactive signatures of concern include radiation dispersal devices (RDD), nuclear warheads, and special nuclear material (SNM). Radiation portal monitors (RPMs) are used as the main screening tool for vehicles and cargo at borders, supplemented by handheld detectors, personal radiation detectors, and x-ray imaging systems. This talk will present an overview of radiation detection equipment with emphasis on radiation portal monitors. In the US, the deployment of radiation detection equipment is being coordinated by the Domestic Nuclear Detection Office within the Department of Homeland Security, and a brief summary of the program will be covered. Challenges with current generation systems will be discussed as well as areas of investigation and opportunities for improvements. The next generation of radiation portal monitors is being produced under the Advanced Spectroscopic Portal program and will be available for deployment in the near future. Additional technologies, from commercially available to experimental, that provide additional information for radiation screening, such as density imaging equipment, will be reviewed. Opportunities for further research and development to improve the current equipment and methodologies for radiation detection for the important task of homeland security will be the final topic to be discussed.

Ely, James

2008-05-01

51

Radiation detection training  

Energy Technology Data Exchange (ETDEWEB)

Apparatus for training personnel in the detection of radio-activity, but without using a radio-active source, includes radio transmitter and a radio receiver which responds to signals received from the transmitter to simulate aspects of a geiger counter. The apparatus establishes the magnitude of a parameter, e.g. the distance between transmitter and receiver and/or the signal strength from the transmitter, and then expresses the magnitude of the parameter on a scale similar to that of a geiger counter and/or produces an intermittent sound similar to that of a geiger counter at a rate according to said magnitude. (author).

Boid, P.G.; Dunham, P.T.; Boid, N.J.

1989-05-04

52

Non-ionizing radiation detection  

International Nuclear Information System (INIS)

sensors network for non-ionizing radiation detection in the band of 800 MHz to 2.5 GHz was designed and constructed. The system is based on a sensor which shows an output DC voltage proportional to the input RF signal. This network is made of four broad band antennas, four circuit board sensors, a main board and data visualization software. The performance system was analyzed changing its configuration and using several radiation sources. The results presented include the simulation of an Archimedes antenna using CST STUDIOTM and the experimental results of a broad band HG2404CU antenna. The results have shown an efficient system for the electromagnetic radiation detection. As a second part of this work, this prototype will be used as a detector of cellular phone calls in places where they are not allowed such as prisons, banks and so on.

2009-01-01

53

A method for detection of hydroxyl radicals in the vicinity of biomolecules using radiation-induced fluorescence of coumarin  

International Nuclear Information System (INIS)

A novel method is described to quantitate radiation-induced hydroxyl radicals in the vicinity of biomolecules in aqueous solutions. Coumarin-3-carboxylic acid (CCA) is a non-fluorescent molecule that, upon interaction with radiation in aqueous solution, produces fluorescent products. CCA was derivatized to its succinimidyl ester (SECCA) and coupled to free primary amines of albumin, avidin, histone-H1, polylysine, and an oligonucleotide. When SECCA-biomolecule conjugates were irradiated, the relationship between induced fluorescence and dose was linear in the dose range examined (0.01-10 Gy). The data indicate that the induction of fluorescence on SECCA-biomolecule conjugates records specifically the presence of the hydroxyl radical in the immediate vicinity of the irradiated biomolecule. The method is rapid and sensitive, uses standard instrumentation, and the sample remains available for further studies. (Author).

1993-01-01

54

Detecting radiation reaction at moderate laser intensities  

CERN Multimedia

We propose a new method of detecting radiation reaction effects in the motion of particles subjected to laser pulses of moderate intensity and long duration. The effect becomes sizeable for particles that gain almost no energy through the interaction with the laser pulse.

Heinzl, Thomas; Ilderton, Anton; Marklund, Mattias; Bulanov, Stepan S; Rykovanov, Sergey; Schroeder, Carl B; Esarey, Eric; Leemans, Wim P

2013-01-01

55

Detection of radiation-induced translocations in A-bomb survivors by fluorescence in situ hybridization (FISH) method  

International Nuclear Information System (INIS)

The present paper describes the results of a collaborative study by RERF, LINL and UCSF on an analysis of the utility of fluorescence in situ hybridization (FISH) with whole-chromosome probes (chromosomes 1, 2 and 4) for measurement of the frequencies of chromosomal translocations that have persisted for decades in the peripheral blood lymphocytes of atomic bomb survivors. In this study, attempts have been made to investigate whether the translocation frequencies measured using FISH agree well with the translocation frequencies measured using both G-banding and conventional Giemsa staining analyses, the latter two techniques of which have been accepted as standard cytogenetic procedures. Sample subjects under study include 20 Hiroshima A-bomb survivors, consisting of 2 distally exposed survivors in the 0-Gy group, and 18 proximally exposed survivors with estimated DS86 kerma ranging from 0.5 to 5.0 Gy. Our preliminary results of measurement of translocations using FISH on A-bomb survivors have indicated that the FISH technique is a useful biological assay system for rapid and accurate detection of induced translocations, and thus for quantification of previous acute exposures to ionizing radiation. Translocation analysis using FISH can also be utilized to assess the level of acute radiation exposure independent of time between exposure and cytogenetic analysis. (author).

1992-01-01

56

Nanocomposite materials for radiation detection  

Science.gov (United States)

Colloidal quantum dots (CdTe, CdSe, and ZnO) have attracted tremendous interest in wide range of application from biological imaging, biosensing, solar cells to optoelectronic devices. However very few published reports on the radiation detection based on colloidal quantum dots. Quantum dots based nanocomposite materials could be a promising material for radiation detection because of their short luminescence life time and high quantum efficiencies as a consequence of quantum size confinement. However stopping power of most quantum dots is low and their scintillation luminescence is very weak. The combination of high stopping power of inorganic scintillator (CeF3LaF3: Ce, YAG:Ce) and high efficiency of quantum dot could potentially lead to a new class of scintillator. We have studied the nanocomposite of inorganic scintillator and quantum dot based on energy transfer principle and investigate the scintillation properties of nanocomposite scintillator.

Sahi, Sunil

2013-03-01

57

Detection of radiation treatment of food  

Energy Technology Data Exchange (ETDEWEB)

A list of foodstuffs is given whose irradiation is permitted in at least one country, as are the purpose of irradiation and permitted doses. A survey is given of the methods used for the detection of radiation treatment and the determination of the applied dose. The principles of chemical methods applied for the testing of irradiated meat, fats, fish and marine products, fruit, mushrooms, sugars, cereals and potatoes are tabulated.

Duchacek, V. (Ustav pro Vyzkum, Vyrobu a Vyuziti Radioisotopu, Prague (Czechoslovakia))

1983-04-01

58

Remote Optical Detection of Alpha Radiation  

International Nuclear Information System (INIS)

Alpha emitting radiation sources are typically hard to detect with conventional detectors due to the short range of alpha particles in the air. However, previous studies have shown that remote detection of alpha radiation is possible by measuring the ionization-induced fluorescence of air molecules. The alpha-induced ultraviolet (UV) light is mainly emitted by molecular nitrogen and its fluorescence properties are well known. The benefit of this method is the long range of UV photons in the air. Secondly, the detection is possible also under a strong beta and gamma radiation backgrounds as they do not cause localized molecular excitation. In this work, the optical detection was studied using two different detection schemes; spectral separation of fluorescence from the background lighting and coincidence detection of UV photons originating from a single radiative decay event. Our spectrally integrated measurements have shown that one alpha decay event yields up to 400 fluorescence photons in the air and all these UV photons are induced in a 5 ns time-window. On the other hand, the probability of a background coincidence event in 5 ns scale is very rare compared to the number of background photons. This information can be applied in fluorescence coincidence filtering to discriminate the alpha radiation initiated fluorescence signal from much more intense background lighting. A device called HAUVA (Handheld Alpha UV Application) was built during this work for demonstration purposes. HAUVA utilizes spectral filtering and it is designed to detect alpha emitters from a distance of about 40 cm. Using specially selected room lighting, the device is able to separate 1 kBq alpha emitter from the background lighting with 1 second integration time. (author)

2010-01-01

59

Cellular telephone-based radiation detection instrument  

Energy Technology Data Exchange (ETDEWEB)

A network of radiation detection instruments, each having a small solid state radiation sensor module integrated into a cellular phone for providing radiation detection data and analysis directly to a user. The sensor module includes a solid-state crystal bonded to an ASIC readout providing a low cost, low power, light weight compact instrument to detect and measure radiation energies in the local ambient radiation field. In particular, the photon energy, time of event, and location of the detection instrument at the time of detection is recorded for real time transmission to a central data collection/analysis system. The collected data from the entire network of radiation detection instruments are combined by intelligent correlation/analysis algorithms which map the background radiation and detect, identify and track radiation anomalies in the region.

Craig, William W. (Pittsburg, CA); Labov, Simon E. (Berkeley, CA)

2011-06-14

60

Optimizing a method for detection of hepatitis A virus in shellfish and study the effect of gamma radiation on the viral genome  

International Nuclear Information System (INIS)

Our work was aimed at detecting the hepatitis A virus (HAV) in bivalve mollusc collected from five shellfish harvesting areas and from a coastal region in Tunisia using RT-Nested-PCR and studying the effect of gamma radiation on HAV genome. Two methods used to recover HAV from mollusc flesh and two methods of extraction of virus RNA were compared in order to determine the most sensitive method. Glycine extraction and extraction of virus RNA using proteinase K were more convenient and then used in this study for detection of HAV in shellfish. The results of molecular analyses: RT-Nested-PCR using primers targeted at the P1 region revealed that 28 % of the samples were positive for HAV. Doses of gamma irradiation ranging between 5 to 30 kGy were used to study the effect of this radiation on HAV genome after the contamination of mollusc flesh with suspension of HAV (derived from stool specimens). HAV specific genomic band was observed for doses between 5 to 20 kGy. We didn't detect HAV genome with doses 25 and 30 kGy. (Author).

2008-01-01

 
 
 
 
61

Application of the microbiological method DEFT/APC to detect minimally processed vegetables treated with gamma radiation  

Energy Technology Data Exchange (ETDEWEB)

Marketing of minimally processed vegetables (MPV) are gaining impetus due to its convenience, freshness and apparent health effect. However, minimal processing does not reduce pathogenic microorganisms to safe levels. Food irradiation is used to extend the shelf life and to inactivate food-borne pathogens. In combination with minimal processing it could improve safety and quality of MPV. A microbiological screening method based on the use of direct epifluorescent filter technique (DEFT) and aerobic plate count (APC) has been established for the detection of irradiated foodstuffs. The aim of this study was to evaluate the applicability of this technique in detecting MPV irradiation. Samples from retail markets were irradiated with 0.5 and 1.0 kGy using a {sup 60}Co facility. In general, with a dose increment, DEFT counts remained similar independent of the irradiation while APC counts decreased gradually. The difference of the two counts gradually increased with dose increment in all samples. It could be suggested that a DEFT/APC difference over 2.0 log would be a criteria to judge if a MPV was treated by irradiation. The DEFT/APC method could be used satisfactorily as a screening method for indicating irradiation processing.

Araujo, M.M.; Duarte, R.C.; Silva, P.V. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Centro de Tecnologia das Radiacoes, Laboratorio de Deteccao de Alimentos Irradiados, Cidade Universitaria, Av. Prof. Lineu Prestes 2242, Butanta Zip Code 05508-000 Sao Paulo (Brazil); Marchioni, E. [Laboratoire de Chimie Analytique et Sciences de l' Aliment (UMR 7512), Faculte de Pharmacie, Universite Louis Pasteur, 74, route du Rhin, F-67400 Illkirch (France); Villavicencio, A.L.C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Centro de Tecnologia das Radiacoes, Laboratorio de Deteccao de Alimentos Irradiados, Cidade Universitaria, Av. Prof. Lineu Prestes 2242, Butanta Zip Code 05508-000 Sao Paulo (Brazil)], E-mail: villavic@ipen.br

2009-07-15

62

Application of the microbiological method DEFT/APC to detect minimally processed vegetables treated with gamma radiation  

Science.gov (United States)

Marketing of minimally processed vegetables (MPV) are gaining impetus due to its convenience, freshness and apparent health effect. However, minimal processing does not reduce pathogenic microorganisms to safe levels. Food irradiation is used to extend the shelf life and to inactivate food-borne pathogens. In combination with minimal processing it could improve safety and quality of MPV. A microbiological screening method based on the use of direct epifluorescent filter technique (DEFT) and aerobic plate count (APC) has been established for the detection of irradiated foodstuffs. The aim of this study was to evaluate the applicability of this technique in detecting MPV irradiation. Samples from retail markets were irradiated with 0.5 and 1.0 kGy using a 60Co facility. In general, with a dose increment, DEFT counts remained similar independent of the irradiation while APC counts decreased gradually. The difference of the two counts gradually increased with dose increment in all samples. It could be suggested that a DEFT/APC difference over 2.0 log would be a criteria to judge if a MPV was treated by irradiation. The DEFT/APC method could be used satisfactorily as a screening method for indicating irradiation processing.

Araújo, M. M.; Duarte, R. C.; Silva, P. V.; Marchioni, E.; Villavicencio, A. L. C. H.

2009-07-01

63

Application of the microbiological method DEFT/APC to detect minimally processed vegetables treated with gamma radiation  

International Nuclear Information System (INIS)

Marketing of minimally processed vegetables (MPV) are gaining impetus due to its convenience, freshness and apparent health effect. However, minimal processing does not reduce pathogenic microorganisms to safe levels. Food irradiation is used to extend the shelf life and to inactivate food-borne pathogens. In combination with minimal processing it could improve safety and quality of MPV. A microbiological screening method based on the use of direct epifluorescent filter technique (DEFT) and aerobic plate count (APC) has been established for the detection of irradiated foodstuffs. The aim of this study was to evaluate the applicability of this technique in detecting MPV irradiation. Samples from retail markets were irradiated with 0.5 and 1.0 kGy using a 60Co facility. In general, with a dose increment, DEFT counts remained similar independent of the irradiation while APC counts decreased gradually. The difference of the two counts gradually increased with dose increment in all samples. It could be suggested that a DEFT/APC difference over 2.0 log would be a criteria to judge if a MPV was treated by irradiation. The DEFT/APC method could be used satisfactorily as a screening method for indicating irradiation processing.

2009-01-01

64

Radiation detection at submillimetre wavelengths  

International Nuclear Information System (INIS)

Techniques and devices for the detection and sensing of radiation in the wavelength range from about 1 mm to 2 ?m are reviewed. Most attention is given to the developments of the past few years, but an attempt is also made to cover the field comprehensively. Brief accounts are given of the characterisation of detection devices, and the general properties of receiver systems, particularly those of the video and heterodyne types. The performance of practical detector devices is then reviewed, most falling into the broad groups of thermal (including 3He and 4He-cooled bolometers), rectifying or photoconductive types. Brief descriptions are given of imaging devices and the present status of heterodyne systems. A steady improvement in the performance of both the newer and the well established devices is reported, but the author points out the need for more accurate calibration of detector performance so that more useful comparisons may be made. (author)

1978-01-01

65

Methods for detecting virulent  

UK PubMed Central (United Kingdom)

Methods for regulating the serine protease of Plasmodium. Recombinant DNA constructs which express the Plasmodium serine protease, especially those comprising a sub2 3'UTR and coding segment which express a SUB2 a serine protease. Recombinant Plasmodium containing such constructs and exhibiting increased virulence. Methods for detecting virulent Plasmodium strains by detecting the presence or amount of sub2 3'UTR sequences, sub2 mRNA or cDNA, SUB2 polypeptide expression, or other Plasmodium proteins, such as AMA1 or MSP1, which have been post-translationally modified by SUB2.

BARALE JEAN-CHRISTOPHE; UZUREAU PIERRICK; BRAUN-BRETON CATHERINE

66

Analysis of effect of the movement of nuclear material on the minimum detectable limit of the radiation detector array using MC method  

International Nuclear Information System (INIS)

The minimum detectable limit of the nuclear radiation detector array is an important technic criteria to judge whether the detector satisfies the detecting requirements or not. From the qualitative point of view, the nuclear material are more difficult to detect when moving than static (namely, the minimum detectable limit is lower when static than moving). This article adopts the Monte Carlo general software--MCNP to compute and analyse the movement of the nuclear component influencing on the minimum detectable limit of the nuclear radiation detector array. The calculated result is in accord with theoretical analysis. (authors)

2007-01-01

67

Application of the microbiological method DEFT/APC and DNA comet assay to detect ionizing radiation processing of minimally processed vegetables  

International Nuclear Information System (INIS)

Marketing of minimally processed vegetables (MPV) are gaining impetus due to its convenience, freshness and apparent healthy. However, minimal processing does not reduce pathogenic microorganisms to safe levels. Food irradiation is used to extend the shelf life and inactivation of food-borne pathogens, Its combination with minimal processing could improve the safety and quality of MPV. Two different food irradiation detection methods, a biological, the DEFT/APC, and another biochemical, the DNA Comet Assay were applied to MPV in order to test its applicability to detect irradiation treatment. DEFT/APC is a microbiological screening method based on the use of the direct epi fluorescent filter technique (DEFT) and the aerobic plate count (APC). DNA Comet Assay detects DNA damage due to ionizing radiation. Samples of lettuce, chard, watercress, dandelion, kale, chicory, spinach, cabbage from retail market were irradiated O.5 kGy and 1.0 kGy using a 60 Co facility. Irradiation treatment guaranteed at least 2 log cycle reduction for aerobic and psychotropic microorganisms. In general, with increasing radiation doses, DEFT counts remained similar independent of irradiation processing while APC counts decreased gradually. The difference of the two counts gradually increased with dose increment in all samples. It could be suggested that a DEFT/APC difference over 2.0 log would be a criteria to judge if a MPV was treated by irradiation. DNA Comet Assay allowed distinguishing non-irradiated samples from irradiated ones, which showed different types of comets owing to DNA fragmentation. Both DEFT/APC method and DNA Comet Assay would be satisfactorily used as a screening method for indicating irradiation processing. (author)

2008-01-01

68

Method of treatment radiation myelopathy  

International Nuclear Information System (INIS)

Method of treatment of the delayed radiation myelopathy is suggested to reduce the period of its treatment. The method is based on using application of dimethylsulfoxide solution to the region of delayed radiation injuries in combination with acupuncture. Treatment with the use of suggested method resulted to reduction of treatment period, occurence of positive dynamics of fibrosis and neurologic symptomatology.

1986-05-14

69

Error detection method  

Energy Technology Data Exchange (ETDEWEB)

An apparatus, program product, and method that run an algorithm on a hardware based processor, generate a hardware error as a result of running the algorithm, generate an algorithm output for the algorithm, compare the algorithm output to another output for the algorithm, and detect the hardware error from the comparison. The algorithm is designed to cause the hardware based processor to heat to a degree that increases the likelihood of hardware errors to manifest, and the hardware error is observable in the algorithm output. As such, electronic components may be sufficiently heated and/or sufficiently stressed to create better conditions for generating hardware errors, and the output of the algorithm may be compared at the end of the run to detect a hardware error that occurred anywhere during the run that may otherwise not be detected by traditional methodologies (e.g., due to cooling, insufficient heat and/or stress, etc.).

Olson, Eric J.

2013-06-11

70

Deterministic methods in radiation transport  

Energy Technology Data Exchange (ETDEWEB)

The Seminar on Deterministic Methods in Radiation Transport was held February 4--5, 1992, in Oak Ridge, Tennessee. Eleven presentations were made and the full papers are published in this report, along with three that were submitted but not given orally. These papers represent a good overview of the state of the art in the deterministic solution of radiation transport problems for a variety of applications of current interest to the Radiation Shielding Information Center user community.

Rice, A.F.; Roussin, R.W. (eds.)

1992-06-01

71

Deterministic methods in radiation transport  

International Nuclear Information System (INIS)

The Seminar on Deterministic Methods in Radiation Transport was held February 4--5, 1992, in Oak Ridge, Tennessee. Eleven presentations were made and the full papers are published in this report, along with three that were submitted but not given orally. These papers represent a good overview of the state of the art in the deterministic solution of radiation transport problems for a variety of applications of current interest to the Radiation Shielding Information Center user community.

1992-01-01

72

Underground tank leak detection methods  

Energy Technology Data Exchange (ETDEWEB)

This book presents a description of leak detection methods for testing underground tank systems. Topics covered include: Volumetric leak detection tests, Non-volumetric leak tests, and Leak detection testing methods.

Niaki, S.; Broscious, J.A.

1989-01-01

73

Radiation Detection Center on the Front Lines  

Energy Technology Data Exchange (ETDEWEB)

Many of today's radiation detection tools were developed in the 1960s. For years, the Laboratory's expertise in radiation detection resided mostly within its nuclear test program. When nuclear testing was halted in the 1990s, many of Livermore's radiation detection experts were dispersed to other parts of the Laboratory, including the directorates of Chemistry and Materials Science (CMS); Physics and Advanced Technologies (PAT); Defense and Nuclear Technologies (DNT); and Nonproliferation, Arms Control, and International Security (NAI). The RDC was formed to maximize the benefit of radiation detection technologies being developed in 15 to 20 research and development (R&D) programs. These efforts involve more than 200 Laboratory employees across eight directorates, in areas that range from electronics to computer simulations. The RDC's primary focus is the detection, identification, and analysis of nuclear materials and weapons. A newly formed outreach program within the RDC is responsible for conducting radiation detection workshops and seminars across the country and for coordinating university student internships. Simon Labov, director of the RDC, says, ''Virtually all of the Laboratory's programs use radiation detection devices in some way. For example, DNT uses radiation detection to create radiographs for their work in stockpile stewardship and in diagnosing explosives; CMS uses it to develop technology for advancing the detection, diagnosis, and treatment of cancer; and the Energy and Environment Directorate uses radiation detection in the Marshall Islands to monitor the aftermath of nuclear testing in the Pacific. In the future, the National Ignition Facility will use radiation detection to probe laser targets and study shock dynamics.''

Hazi, A

2005-09-20

74

Radiation Detection Center on the Front Lines  

International Nuclear Information System (INIS)

Many of today's radiation detection tools were developed in the 1960s. For years, the Laboratory's expertise in radiation detection resided mostly within its nuclear test program. When nuclear testing was halted in the 1990s, many of Livermore's radiation detection experts were dispersed to other parts of the Laboratory, including the directorates of Chemistry and Materials Science (CMS); Physics and Advanced Technologies (PAT); Defense and Nuclear Technologies (DNT); and Nonproliferation, Arms Control, and International Security (NAI). The RDC-- was formed to maximize the benefit of radiation detection technologies being developed in 15 to 20 research and development (R and D) programs. These efforts involve more than 200 Laboratory employees across eight directorates, in areas that range from electronics to computer simulations. The RDC's primary focus is the detection, identification, and analysis of nuclear materials and weapons. A newly formed outreach program within the RDC-- is responsible for conducting radiation detection workshops and seminars across the country and for coordinating university student internships. Simon Labov, director of the RDC, says, ''Virtually all of the Laboratory's programs use radiation detection devices in some way. For example, DNT uses radiation detection to create radiographs for their work in stockpile stewardship and in diagnosing explosives; CMS uses it to develop technology for advancing the detection, diagnosis, and treatment of cancer; and the Energy and Environment Directorate uses radiation detection in the Marshall Islands to monitor the aftermath of nuclear testing in the Pacific. In the future, the National Ignition Facility will use radiation detection to probe laser targets and study shock dynamics.''

2005-01-01

75

Geoelectrical frac detection method  

Energy Technology Data Exchange (ETDEWEB)

With the geoelectric detection method, developed as part of a research project by Prakla-Seismos GmbH, a tool which can exactly determine the orientation of hydraulic fractures at depths of 4,000 m and more has been developed. The survey method is operated at the earth's surface. An extremely high current is passed into the subsurface via the casing of the fracture well and a second electrode is situated far away using a specially constructed equipment. A number of potential electrodes, arranged symmetrically around the fracture well, register the electric field before and after fracturing. As the liquid-filled fracture acts as an additional electric conductor, the 2 measured potential fields are different. From the distortion of the second potential field it is possible to determine the orientation of the fracture.

Hardt, I.

1982-09-01

76

Method for detecting urease  

UK PubMed Central (United Kingdom)

A system and method for detecting bacterial infections in the gastrointestinal tract is disclosed. In one embodiment, the system includes a first composition separated from a second composition. The first composition contains urea in powdered form. The second composition, on the other hand, contains an indicator. A biopsy of a gastric sample is first contacted with the first composition and then placed in the second composition. The second composition indicates the presence of an enzyme that, in turn, indicates the presence of bacteria. In an alternative embodiment of the present invention, a biopsy of a gastric sample is contacted with a single composition. The composition contains urea in a powdered form combined with a dry indicator. Besides urea and a dry indicator, the composition can also contain an anti-caking agent.

MARSHALL BARRY J; MENDIS ARUNI H.W; CHAIRMAN SIMON; MENDIS ARUNI H. W

77

Atomic bomb radiation dosimetry with ESR method  

International Nuclear Information System (INIS)

The availability of electron spin resonance (ESR) spectroscopy was evaluated in estimating radiation doses in atomic bomb (A-bomb) victims. Teeth, shell button of clothes, and part of the surface of the femur were collected as materials from 7 A-bomb victims. Radiation-induced ESR signals increased in proportional to radiation doses of gamma-rays. A background signal was detected at g value near to the target signal, which was largely different according to the materials. Measurement limits were various. The ESR method allowed small doses of gamma-rays to be estimated with errors of +- 50 % when materials had small background. This method can be used repeatedly because captured electrons are not released by vibration of microwaves. It permits the measurement of living materials which are unmeasurable by thermoluminescence dosimeter, and the estimation of radiation doses even when shielding factors are unknown. (Namekawa, K.).

1984-01-01

78

Physics and engineering of radiation detection  

CERN Document Server

Physics and Engineering of Radiation Detection presents an overview of basic physics of radiation and its applications and covers the origins and properties of different kinds of ionizing radiation, their detection and measurement, and the procedures used to protect people and the environment from their potentially harmful effects. Covering both the basic physics of radiation and its applications, it will provide an up-to-date and coherent account of the origins and properties of the different kinds of ionizing radiation, and their detection and measurement. This book will illustrate the basic physical principles with an abundance of practical, worked-out examples, numerical problems, real world applications, and data, including biological effects, radon, risk assessment, and statistics.

Ahmed, Syed Naeem

2007-01-01

79

Efficiency of cytogenetic methods in detecting a chromosome rearrangement induced by ionizing radiation in a cultivated chili pepper line (Capsicum baccatum var. pendulum - SOLANACEAE).  

UK PubMed Central (United Kingdom)

Abstract Purpose: The present study was designed to locate transient chromosome aberrations on a selected pepper cultivar and determine the tracing efficiency of different cytogenetic methods. Materials and methods: Seeds from Capsicum baccatum var. pendulum cultivar "Cayenne" were treated with an acute dose of X-rays (300 Gy) and chromosome aberrations were analysed by different cytogenetic methods [Feulgen, silver staining for nucleolus organizer regions (silver positive nucleolus organizing regions or AgNOR), fluorescent banding, fluorescence in situ hybridization (FISH) and meiotic analysis]. Results: A rearranged chromosome carrying two nucleolus organizing regions (NOR) induced by ionizing radiation was detected in the cultivar, with the occurrence of a small reciprocal exchange between a chromosome of pair no. 1 and another chromosome of pair no. 3, both carrying active NOR in short arms and associated chromomycin A positive / diamidino - phenylindole negative (CMA+/DAPI-) heterochromatin. Meiotic analysis showed a quadrivalent configuration, confirming a reciprocal translocation between two chromosomes. Conclusions: The use of X-rays in Capsicum allowed us to develop and identify a pepper line with structural rearrangements between two NOR-carrying chromosomes. We postulate that all the cytological techniques employed in this research were efficient in the search for chromosome aberrations. Particularly, Feulgen and AgNOR were the most suitable in those cases of transient rearrangements, whereas fluorescent banding and FISH were appropriate for intransitive ones.

Scaldaferro MA; Grabiele M; Seijo JG; Debat H; Romero MV; Ducasse DA; Prina AR; Moscone EA

2013-07-01

80

Detection of nuclear warheads by radiation  

International Nuclear Information System (INIS)

Attention has been focused on the technique to utilize nuclear radiation as a promising means of detecting nuclear warheads loaded on board warships or bombers. Such a method will be very useful as a practical measure of verification necessary to the conclusion of any treaty for nuclear disarmament which is under negotiation between USA and USSR. It may also be used by Japan to ascertain whether the foreign warships calling Japanese ports carry nuclear weapons or not. Recently, the Federation of American Scientists and the Committee of Soviet Scientists for Peace and against Nuclear Threat have advanced the Cooperative Verification Project about such a detection technique on a nongovernmental basis. In July, 1989, they conducted for the first time the joint experiment on warhead detection in the Black Sea under the full cooperation of Soviet Navy, and succeeded in obtaining a number of interesting results. In this report, the main results are given, and some remarks on the possibility of extending the method to the remote monitoring of the clandestine introduction of nuclear weapons by foreign vessels are made. The comparison of the various methods and the experiment in the Black Sea are reported. (K.I.).

1990-01-01

 
 
 
 
81

Current trends in ionizing radiation detection  

Energy Technology Data Exchange (ETDEWEB)

Ionizing radiation is a both a natural and man-made phenomena that plays a major role in contemporary applications. The detection of this radiation has evolved over the past several decades from simple observations to precise measurements in space, time, and energy, even in harsh environmental conditions. In this paper, we present a snapshot of the current state-of-the-art in radiation measurement technology, highlighting the major applications and detector developments.

Wehe, David K. [University of Michigan, Ann Arbor (United States)

2006-06-15

82

Ellipsoid-conic radiation collector and method  

Energy Technology Data Exchange (ETDEWEB)

Disclosed is a radiation collector apparatus and method primarily for counting and analyzing a flow of dilute particulate material, such as blood cells, sperm cells and the like, through the use of light detection. The radiation collector apparatus comprises a reflector chamber having an ellipsoidal reflector surface with a pair of elipsoidal foci defining a first focus, f11, and second focus, f12, and a second reflector surface with a primary focus, f21, positioned at the same point as focus f12, and a secondary focus, f22. The second reflector surface has the configuration of one of the conic sections of revolution. In operation the radiation collector apparatus is provided with an intensifed beam of light and a stream of particulate material aligned to intersect the intensifed beam of light at focus f11. Detectable light signals, after two reflections, are received in a focused beam by a photosensitive detector.

Brunsting, A.; Hogg, W.R.

1980-02-19

83

CLOUD DETECTION METHODS – A REVIEW  

Directory of Open Access Journals (Sweden)

Full Text Available Cloud detection is a one of the most important processes in weather predication and regional planning. Detection of clouds helps to improve the efficiency in study of climatic changes. Different methods are in use and most of the methods have its own implementation issues. This paper explains widely used cloud detection methods and its challenges.

B.RAMESH; SATHEESH KUMAR

2013-01-01

84

Silicon solid state devices and radiation detection  

CERN Multimedia

This book addresses the fundamental principles of interaction between radiation and matter, the principles of working and the operation of particle detectors based on silicon solid state devices. It covers a broad scope with respect to the fields of application of radiation detectors based on silicon solid state devices from low to high energy physics experiments including in outer space and in the medical environment. This book covers stateof- the-art detection techniques in the use of radiation detectors based on silicon solid state devices and their readout electronics, including the latest developments on pixelated silicon radiation detector and their application.

Leroy, Claude

2012-01-01

85

Electrochemical gas detection method  

Energy Technology Data Exchange (ETDEWEB)

An electrochemical cell comprising an anode, a cathode and a reference electrode operating in an aqueous electrolyte is utilized for detection of noxious gases in air. The gas is oxidized at the anode and detection thereof occurs as a result of the current generated by the reaction. A fixed potential difference is maintained between the anode and the reference electrode to avoid generation of undesired current from reactions involving an oxygen-water redox couple within the cell which would invalidate anode-cathode current for gas detection purposes. The fixed potential is chosen from within the range of about 0.9 to 1.5 volts.

Oswin, H. G.; Blurton, K. F.

1985-06-18

86

Synchrotron Radiation X-Ray Phase Micro-computed Tomography as a New Method to Detect Iron Oxide Nanoparticles in the Brain.  

UK PubMed Central (United Kingdom)

PURPOSE: The purpose of this study was to introduce synchrotron radiation X-ray phase computed tomography (SR-PCT) as a new method of visualizing ultrasmall superparamagnetic particles of iron oxide (USPIO) distribution into the brains of mice with neuroinflammation. PROCEDURES: The sensitivity of the technique was assessed by performing back-to-back SR-PCT and magnetic resonance imaging (MRI) in mice stereotaxically injected with a range of USPIO concentrations. Eight mice with cerebral ischemia were then intravenously injected with USPIOs and imaged back-to-back with MRI and SR-PCT. RESULTS: SR-PCT proved sensitive enough to detect iron in nanomolar quantities. In stroke-induced animals, SR-PCT showed hyperintense areas in the regions of MR signal loss and immunostaining for macrophages. SR-PCT, moreover, identified brain anatomy as clearly as histology, without the need for sectioning or staining, with an examination time of 44 min per brain at an isotropic spatial resolution of 8 ?m. CONCLUSION: SR-PCT has potential for cellular imaging in intact brain, with unequaled neuroanatomy.

Marinescu M; Langer M; Durand A; Olivier C; Chabrol A; Rositi H; Chauveau F; Cho TH; Nighoghossian N; Berthezène Y; Peyrin F; Wiart M

2013-10-01

87

Gravitational Radiation Detection with Laser Interferometry  

CERN Multimedia

Gravitational-wave detection has been pursued relentlessly for over 40 years. With the imminent operation of a new generation of laser interferometers, it is expected that detections will become a common occurrence. The research into more ambitious detectors promises to allow the field to move beyond detection and into the realm of precision science using gravitational radiation. In this article, I review the state of the art for the detectors and describe an outlook for the coming decades.

Adhikari, Rana X

2013-01-01

88

Electrets for beta radiation detection  

International Nuclear Information System (INIS)

[en] Electret dosimetry has been reviewed by Gross. A cylindrical electret ionization-chamber type dosimeter has been studied for X and gamma rays and neutrons. The principle of the dosimeter is electret charge compensation due to ionization in the chamber volume. Electret ionization chambers can be designed with one or more electrets and in various shapes. This study is concerned with a simple system, similar to a cylindrical ionization chamber (sensitive volume: 3,5 cm3) using teflon electrets. Aluminum and lucite were used as wall-materials. Other experiences were performed using chambers without wall, i.e., without defined sensitive volume. The teflon electrets were obtained by Corona discharge in the gas surrounding them. The measurement of the electret charge was made by induction using a co-axial insulated metal chamber connected to an electrometer Keithley 610C. By measuring the charge before and after irradiation it is possible to obtain a calibration curve: charge (Q) versus absorbed dose (D) for the dosimeter. The irradiation setup used was the Beta Secondary Standard System of IPEN calibration laboratory with four beta sources: 90Sr90Y (74 and 1850 MBq), 204Tl (18,5 MBq) and 147Pm (518 MBq). In some cases a 85Kr source was also used. The electrets were tested in different radiation field geometries: electret axis parallel and perpendicular to the field. In conclusion, depending on the wall material and radiation field geometry, the teflon electret detector can be used for different dose interval determinations, using beta radiation

1983-01-01

89

Flaw detection methods reviewed  

Energy Technology Data Exchange (ETDEWEB)

In-service inspection aims to detect metallurgical flaws which could constitute a safety hazard or cause costly failures. The growth of nuclear in-service inspection which has stimulated developments in all of the accepted non-destructive testing techniques and particularly in ultrasonics is reviewed. The performance of in-service inspection, choice of procedures, and how effective they are in detecting significant flaws are discussed. A brief description is given of the techniques available; dye penetrant, magnetic particle inspection, radiography, ultrasonics, eddy currents and acoustic emission.

Harper, H. (Central Electricity Generating Board, Manchester (UK). Scientific Services Dept.)

1981-12-01

90

Flaw detection methods reviewed  

International Nuclear Information System (INIS)

In-service inspection aims to detect metallurgical flaws which could constitute a safety hazard or cause costly failures. The growth of nuclear in-service inspection which has stimulated developments in all of the accepted non-destructive testing techniques and particularly in ultrasonics is reviewed. The performance of in-service inspection, choice of procedures, and how effective they are in detecting significant flaws are discussed. A brief description is given of the techniques available; dye penetrant, magnetic particle inspection, radiography, ultrasonics, eddy currents and acoustic emission. (U.K.)

1981-01-01

91

GaTe semiconductor for radiation detection  

Energy Technology Data Exchange (ETDEWEB)

GaTe semiconductor is used as a room-temperature radiation detector. GaTe has useful properties for radiation detectors: ideal bandgap, favorable mobilities, low melting point (no evaporation), non-hygroscopic nature, and availability of high-purity starting materials. The detector can be used, e.g., for detection of illicit nuclear weapons and radiological dispersed devices at ports of entry, in cities, and off shore and for determination of medical isotopes present in a patient.

Payne, Stephen A. (Castro Valley, CA); Burger, Arnold (Nashville, TN); Mandal, Krishna C. (Ashland, MA)

2009-06-23

92

Detection of radiation pressure from solar chameleons  

CERN Multimedia

The radiation pressure due to reflected chameleons is suggested for their detection. Sensitive photon radiation pressure or force measuring techniques could become the new antennas for chameleons or other particles with similar properties, with gravitational waves antennas being also of potential interest. This is eventually only at first sight a Gedankenexperiment. Also chameleon-through-a-wall experiments, in particular when equipped with a Fabry-Perot resonator, could apply the suggested techniques.

Baker, O K; Semertzidis, Y K; Upadhye, A; Zioutas, K

2012-01-01

93

Methods for detecting oncofetal fibronectin  

UK PubMed Central (United Kingdom)

Methods and products for the detection of oncofetal fibronectin indicating molecules in samples are provided. Methods for imaging of oncofetal fibronectin are provided. In some methods provided herein, the sample is treated with a reagent and/or contacted with a non-specific binder. Provided are methods for testing subjects to ascertain health and disease status and to assess the risk of developing a disease or condition. Methods for detecting the presence of oncofetal fibronectin indicating molecules by a variety of methods such as immunoassays and mass spectrometry also are provided. Methods and products for detection of oncofetal fibronection for selection of concepti are provided.

HUSSA ROBERT; FISCHER-COLBRIE MARK; LAPOINTE JEROME P; SHORTER SIMON; SENYEI ANDREW '

94

Detection methods for irradiated food  

International Nuclear Information System (INIS)

The detection methods for irradiated food are presented. There is no general method applicable to all foods and thus a range of tests based on physical, chemical, microbiological and biological alterations in food are being developed. The suitable detection method can help to disseminate the application of irradiation technique in the food industry. (author).

1995-01-01

95

Mobile Radiation Detection System against Nuclear Terrorism  

International Nuclear Information System (INIS)

After the September 11th, 2001, terrorist attacks in the USA, the discovery of Al-Qaeda's experimentation to build dirty bomb and the death of a former officer of the Russian Federal Security Service from Po-210- induced acute radiation exposure, the threats relating to nuclear and radioactive materials have become a matter of increased international concern. Detection of illicit transport and trafficking of nuclear and radioactive materials is necessary for prevention of nuclear terrorism, since failure in detection might lead to catastrophic results. A mobile radiation detection system plays an important role in preventing the potential dangers posed by illicit transport and trafficking of such dangerous materials because it can monitor the suspicious vehicle at place beyond terrorist's expectation which makes intentionally a detour about the portal monitor deployed at seaports, airports, and key traffic checkpoints. The mobile radiation detection system using one NaI, two plastic scintillation, and two He-3 detectors has been developed. This paper describes the developed mobile radiation detection system and experimental results for its performance assessment

2009-01-01

96

The health status of grandchildren of subjects occupationally exposed to chronic radiation. Communication 1. Methods for detection and assessment of deviation in the health status  

International Nuclear Information System (INIS)

[en] The task of this study was development of methodological approaches to integral assessment of the health status of the grandchildren of subjects who had been occupationally exposed to chronic radiation. A register has been charted for recording the health indices and characteristics of a complex of social, biological, and medical factors in three main groups of children (grandchildren of irradiated subjects) and in one control group. Creation of a data bank helped comprehensively assess the health status of the grandchildren of exposed subjects and evaluate the rule of the radiation factor among other factors causing diseases. The methods of mathematical processing used in this study have been validated and are described

1996-01-01

97

Flame failure detection method  

Energy Technology Data Exchange (ETDEWEB)

A method is described of operating a gas turbine engine having a combustor, comprising: establishing a fuel demand signal; sending a fuel quantity to said combustor in response to said fuel demand signal; burning said fuel in said combustor; generating an air flow as a function of the fuel being burnt; sensing a measure of said airflow; producing a fuel demand/air flow ratio; comparing said ratio to a preselected value; and declaring a flameout when said ratio exceeds said preselected value.

Barnum, B.M.; Bell, R.C.

1993-08-17

98

Measuring element for the detection and determination of radiation doses of gamma radiation and neutrons  

International Nuclear Information System (INIS)

A measuring element detects and proves both gamma and neutron radiation. The element includes a photoluminescent material which stores gamma radiation and particles of arsenic and phosphorus embedded in the photoluminescent material for detecting neutron radiation. (U.S.)

1975-01-01

99

Waveshifters and Scintillators for Ionizing Radiation Detection  

Energy Technology Data Exchange (ETDEWEB)

Scintillation and waveshifter materials have been developed for the detection of ionizing radiation in an STTR program between Ludlum Measurements, Inc. and the University of Notre Dame. Several new waveshifter materials have been developed which are comparable in efficiency and faster in fluorescence decay than the standard material Y11 (K27) used in particle physics for several decades. Additionally, new scintillation materials useful for fiber tracking have been developed which have been compared to 3HF. Lastly, work was done on developing liquid scintillators and paint-on scintillators and waveshifters for high radiation environments.

B.Baumgaugh; J.Bishop; D.Karmgard; J.Marchant; M.McKenna; R.Ruchti; M.Vigneault; L.Hernandez; C.Hurlbut

2007-12-11

100

Radon in buildings: a simple detection method  

International Nuclear Information System (INIS)

Natural background radiation inside buildings can be studied using this simple detection method. Contaminated dust particles adhere readily to a membrane made of soft toilet paper placed across the collection pipe of a vacuum cleaner. Indirect evidence for the abundance of radon in the air can be inferred from measuring the radon daughters on the membrane using a Geiger-Muller tube. Experimental results are presented and discussed. (UK)

1989-01-01

 
 
 
 
101

Surface property detection apparatus and method  

Energy Technology Data Exchange (ETDEWEB)

Apparatus and method for detecting, determining, and imaging surface resistance corrosion, thin film growth, and oxide formation on the surface of conductors or other electrical surface modification. The invention comprises a modified confocal resonator structure with the sample remote from the radiating mirror. Surface resistance is determined by analyzing and imaging reflected microwaves; imaging reveals anomalies due to surface impurities, non-stoichiometry, and the like, in the surface of the superconductor, conductor, dielectric, or semiconductor.

Martens, Jon S. (Albuquerque, NM); Ginley, David S. (Evergreen, CO); Hietala, Vincent M. (Placitas, NM); Sorensen, Neil R. (Albuquerque, NM)

1995-01-01

102

Energy detection method and apparatus  

International Nuclear Information System (INIS)

A method is described of detecting neutrinos comprising the steps of irradiating a material with the neutrinos to cause coherent stimulated emission of radiant energy fields in the material in response to the material being irradiated by the neutrinos, and detecting the coherent radiant energy fields.

1986-01-01

103

Energy detection method and apparatus  

Energy Technology Data Exchange (ETDEWEB)

A method is described of detecting neutrinos comprising the steps of irradiating a material with the neutrinos to cause coherent stimulated emission of radiant energy fields in the material in response to the material being irradiated by the neutrinos, and detecting the coherent radiant energy fields.

Weber, J.

1986-03-18

104

Method of detecting periodontal disease  

UK PubMed Central (United Kingdom)

Method for detecting periodontal disease using bacterial and genetic tests comprises detecting specific variations of genes coding for interleukin (IL)-1alpha (-889) and IL-1 beta (+3953) and measuring allele 2 of IL-1alpha (-889) and/or allele 2 of IL-1beta (+3953).

COHEN-LORO YVES

105

Plasmonically enhanced thermomechanical detection of infrared radiation.  

UK PubMed Central (United Kingdom)

Nanoplasmonics has been an attractive area of research due to its ability to localize and manipulate freely propagating radiation on the nanometer scale for strong light-matter interactions. Meanwhile, nanomechanics has set records in the sensing of mass, force, and displacement. In this work, we report efficient coupling between infrared radiation and nanomechanical resonators through nanoantenna enhanced thermoplasmonic effects. Using efficient conversion of electromagnetic energy to mechanical energy in this plasmo-thermomechanical platform with a nanoslot plasmonic absorber integrated directly on a nanobeam mechanical resonator, we demonstrate room-temperature detection of nanowatt level power fluctuations in infrared radiation. We expect our approach, which combines nanoplasmonics with nanomechanical resonators, to lead to optically controlled nanomechanical systems enabling unprecedented functionality in biomolecular and toxic gas sensing and on-chip mass spectroscopy.

Yi F; Zhu H; Reed JC; Cubukcu E

2013-04-01

106

Analytical detection methods for irradiated foods  

International Nuclear Information System (INIS)

The present publication is a review of scientific literature on the analytical identification of foods treated with ionizing radiation and the quantitative determination of absorbed dose of radiation. Because of the extremely low level of chemical changes resulting from irradiation or because of the lack of specificity to irradiation of any chemical changes, a few methods of quantitative determination of absorbed dose have shown promise until now. On the other hand, the present review has identified several possible methods, which could be used, following further research and testing, for the identification of irradiated foods. An IAEA Co-ordinated Research Programme on Analytical Detection Methods for Irradiation Treatment of Food ('ADMIT'), established in 1990, is currently investigating many of the methods cited in the present document. Refs and tab.

1991-01-01

107

Method of designing radiation shielding  

Energy Technology Data Exchange (ETDEWEB)

In a case where a plurality of radiation generators, such as charged particle accelerators are disposed in adjacent with each other, since the maximum intensity of radiation rays does not corresponded to the maximum radiation dose on a radiation dose measuring plane, automatic calculation can not be conducted. Then, in the present invention, a great number of measuring points are set on the radiation measuring plane which is divided depending on the radiation shielding members having different shielding effects. For each of the measuring points, the radiation shielding members are indicated on an infinite plane, radiation doses leaked from a radiation generating sources are calculated and they are summed up to calculate the leaked radiation dose at each of the measuring points. The calculation can be conducted by a computer programming, and since all of the radiation generation sources contribute to the summed-up leaked radiation dose at each of the measuring points, the radiation shielding members can be designed depending on the maximum dose. Then, the radiation shielding member can be designed to the minimum size to minimize the radiation generator, thereby enabling to reduce the cost. (N.H.).

Okuda, Soichiro; Nakagawa, Takafumi.

1991-10-25

108

Radiation techniques for detection of explosives  

International Nuclear Information System (INIS)

The detection of explosive material in airport baggage requires a device that can quickly detect a small amount of explosives with a high success rate and a low positive false alarm rate. The device should be able to handle carry-on as well as checked baggage and should provide indications that are independent of the geometric configuration of the material. The mass density of an explosive compound is relatively high. Also, explosives have high nitrogen and oxygen densities. Most detection techniques exploit the nitrogen-rich nature of explosives. Although few materials have such a high nitrogen density, some plastics, clothing materials and narcotics have also high nitrogen content. In order to distinguish such innocuous materials from explosives, one needs to detect the presence of other elements, particularly oxygen. The measurement of high oxygen density in the inspected object, together with a high nitrogen density, provides a strong indication that the object contains an explosive material. This is the minimum requirement for unambiguous determination of the presence of explosives. An additional measurement will decrease the degree of ambiguity and increase the reliability of the system. A number of radiation based techniques have been developed, or are being considered for the detection of explosives. This paper reviews some of these techniques, based on the type and mode of interaction of the radiation employed

1995-01-01

109

Composite scintillators for detection of ionizing radiation  

Energy Technology Data Exchange (ETDEWEB)

Applicant's present invention is a composite scintillator having enhanced transparency for detecting ionizing radiation comprising a material having optical transparency wherein said material comprises nano-sized objects having a size in at least one dimension that is less than the wavelength of light emitted by the composite scintillator wherein the composite scintillator is designed to have selected properties suitable for a particular application.

Dai, Sheng (Knoxville, TN); Stephan, Andrew Curtis (Knoxville, TN); Brown, Suree S. (Knoxville, TN); Wallace, Steven A. (Knoxville, TN); Rondinone, Adam J. (Knoxville, TN)

2010-12-28

110

Composition and apparatus for detecting gamma radiation  

Energy Technology Data Exchange (ETDEWEB)

A gamma radiation detector and a radioluminiscent composition for use therein. The detector includes a radioluminscent composition that emits light in a characteristic wavelength region when exposed to gamma radiation, and means for detecting said radiation. The composition contains a scintillant such as anglesite (PbSO.sub.4) or cerussite (PbCO.sub.3) incorporated into an inert, porous glass matrix via a sol-gel process. Particles of radiation-sensitive scintillant are added to, a sol solution. The mixture is polymerized to form a gel, then dried under conditions that preserve the structural integrity and radiation sensitivity of the scintillant. The final product is a composition containing the uniformly-dispersed scintillant in an inert, optically transparent and highly porous matrix. The composition is chemically inert and substantially impervious to environmental conditions including changes in temperature, air pressure, and so forth. It can be fabricated in cylinders, blocks with holes therethrough for flow of fluid, sheets, surface coatings, pellets or other convenient shapes.

Hofstetter, Kenneth J. (Aiken, SC)

1994-01-01

111

Method and apparatus for radiation dose measurement  

International Nuclear Information System (INIS)

A method is described for determining an irradiation dose comprising the steps of: (a) subjecting a solution of known concentrations of ceric and cerous ions, in the presence of sulphuric acid, to gamma or electron irradiation, (b) measuring the electrochemical potential difference, in a suitable detecting cell, between an unirradiated solution containing known concentrations of ceric and cerous ions and the irradiated solution which initially contained the same known concentrations of ceric and cerous ions so as to produce a signal proportional to the electrochemical potential difference, and (c) converting the signal electronically to give an output proportional to the radiation dose received by the irradiated solution. (author)

1972-10-16

112

Calculating gamma radiation field gradient by the Monte Carlo method  

International Nuclear Information System (INIS)

An algorithm for direct calculation of gradients of photon flux density, energy flux and radiation doze by the Monte Carlo method is suggested. Local evaluation for a point detector, depending on collision ooint and scattering angle cosine is applied to calculate ?-radiation flux density gradient in the point of detecting. Results of calculating the scattered radiation flux density and the corresponding gradient behind the indefinite two-layer barrier of aluminium and carbon are presented as an example

1985-01-01

113

Plastic scintillator-based radiation detector for mobile radiation detection system against nuclear/radiological terrorism  

International Nuclear Information System (INIS)

Illicit trafficking of nuclear or radioactive materials has become a serious world wide problem. Due to operational constraints of radiation detection system for such nuclear security application, a radiation detector with large effective area is needed to maximize its sensitivity. This paper suggests a new method of using plastic scintillation detector as a cost-effective mobile radiation detection system. Monte Carlo simulation code, MCNPX, has been used to analyze spectral distribution available from the plastic detector and to derive algorithmic process with a view to discriminating targeted sources from ambient background radiation. Theoretical results in present work showed that the targeted sources which might be used for nuclear/radiological terrorism could be discriminated from Nationally Occurring Radioactive Material (NORM) or background.

2009-06-01

114

Methodical support of the radiation control  

International Nuclear Information System (INIS)

The program of combined standardization of both methods and means of the radiation control is developed and realized in Belarus. A number of the standards and other normative documents on methodical maintenance of the radiation control is prepared. The projects on creation of reference base in a field of ionizing radiations are carried out.

1997-01-01

115

A new vehicle detection method  

Directory of Open Access Journals (Sweden)

Full Text Available This paper presents a new vehicle detection method from images acquired by cameras embedded in a moving vehicle. Given the sequence of images, the proposed algorithms should detect out all cars in realtime. Related to the driving direction, the cars can be classified into two types. Cars drive in the same direction as the intelligent vehicle (IV) and cars drive in the opposite direction. Due to the distinct features of these two types, we suggest to achieve this method in two main steps. The first one detects all obstacles from images using the so-called association combined with corner detector. The second step is applied to validate each vehicle using AdaBoost classifier. The new method has been applied to different images data and the experimental results validate the efficacy of our method.

Zebbara Khalid; Mohamed El Ansari; Abdenbi Mazoul

2011-01-01

116

Cellular telephone-based wide-area radiation detection network  

Energy Technology Data Exchange (ETDEWEB)

A network of radiation detection instruments, each having a small solid state radiation sensor module integrated into a cellular phone for providing radiation detection data and analysis directly to a user. The sensor module includes a solid-state crystal bonded to an ASIC readout providing a low cost, low power, light weight compact instrument to detect and measure radiation energies in the local ambient radiation field. In particular, the photon energy, time of event, and location of the detection instrument at the time of detection is recorded for real time transmission to a central data collection/analysis system. The collected data from the entire network of radiation detection instruments are combined by intelligent correlation/analysis algorithms which map the background radiation and detect, identify and track radiation anomalies in the region.

Craig, William W. (Pittsburg, CA); Labov, Simon E. (Berkeley, CA)

2009-06-09

117

Neutron Radiation System for Explosives Detection in Cargo Containers  

International Nuclear Information System (INIS)

A measuring inspection system created in VNIIA and intended for active interrogation of cargo containers to detect explosives is presented. The system is based on (a) the 14 MeV 'tagged' neutron method in combination with nanosecond neutron analysis, and (b) the detection of characteristic secondary gamma-radiation from the reaction of inelastic neutron scattering on sample objects. Experimental results for the detection of an explosive simulator - melamine (C3H6N6) are presented for different container loadings (wood, iron) and for different arrangements of the explosive simulator. (author)

2010-01-01

118

Adaptable radiation monitoring system and method  

Energy Technology Data Exchange (ETDEWEB)

A portable radioactive-material detection system capable of detecting radioactive sources moving at high speeds. The system has at least one radiation detector capable of detecting gamma-radiation and coupled to an MCA capable of collecting spectral data in very small time bins of less than about 150 msec. A computer processor is connected to the MCA for determining from the spectral data if a triggering event has occurred. Spectral data is stored on a data storage device, and a power source supplies power to the detection system. Various configurations of the detection system may be adaptably arranged for various radiation detection scenarios. In a preferred embodiment, the computer processor operates as a server which receives spectral data from other networked detection systems, and communicates the collected data to a central data reporting system.

Archer, Daniel E. (Livermore, CA); Beauchamp, Brock R. (San Ramon, CA); Mauger, G. Joseph (Livermore, CA); Nelson, Karl E. (Livermore, CA); Mercer, Michael B. (Manteca, CA); Pletcher, David C. (Sacramento, CA); Riot, Vincent J. (Berkeley, CA); Schek, James L. (Tracy, CA); Knapp, David A. (Livermore, CA)

2006-06-20

119

Detecting transition radiation from a magnetic moment.  

UK PubMed Central (United Kingdom)

Electromagnetic radiation can be emitted not only by particle charges but also by magnetic moments and higher electric and magnetic multipoles. However, experimental proofs of this fundamental fact are extremely scarce. In particular, the magnetic moment contribution has never been observed in any form of polarization radiation. Here, we propose to detect it using vortex electrons carrying large orbital angular momentum ?. The relative contribution of the orbital angular momentum-induced magnetic moment, ???/Ee, becomes much larger than the spin-induced contribution ??/E and it can be observed experimentally. As a particular example, we consider transition radiation from vortex electrons obliquely incident on an interface between a vacuum and a dispersive medium, in which the magnetic moment contribution manifests itself via a left-right angular asymmetry. For electrons with Ee=300??keV and ?=100-1000, we predict an asymmetry of the order of 0.1%-1%, which could be measured with existing technology. Thus, vortex electrons emerge as a new tool in the physics of electromagnetic radiation.

Ivanov IP; Karlovets DV

2013-06-01

120

Detecting transition radiation from a magnetic moment.  

Science.gov (United States)

Electromagnetic radiation can be emitted not only by particle charges but also by magnetic moments and higher electric and magnetic multipoles. However, experimental proofs of this fundamental fact are extremely scarce. In particular, the magnetic moment contribution has never been observed in any form of polarization radiation. Here, we propose to detect it using vortex electrons carrying large orbital angular momentum ?. The relative contribution of the orbital angular momentum-induced magnetic moment, ???/Ee, becomes much larger than the spin-induced contribution ??/E and it can be observed experimentally. As a particular example, we consider transition radiation from vortex electrons obliquely incident on an interface between a vacuum and a dispersive medium, in which the magnetic moment contribution manifests itself via a left-right angular asymmetry. For electrons with Ee=300??keV and ?=100-1000, we predict an asymmetry of the order of 0.1%-1%, which could be measured with existing technology. Thus, vortex electrons emerge as a new tool in the physics of electromagnetic radiation. PMID:23848881

Ivanov, Igor P; Karlovets, Dmitry V

2013-06-26

 
 
 
 
121

Radiation shield, radiation irradiation system and radiation shielding method  

Energy Technology Data Exchange (ETDEWEB)

The present invention provides a structure of shielding walls for shielding radiation, which is light in weight, small in the size, and can be constructed, replaced, attached and detached conveniently and relatively easily. Namely, the radiation shield of the present invention is formed by vessels capable of charging/discharging fluid for shielding radiation. The fluid may be water and the vessel may be a water vessel. The structure may be a radiation shield comprising a plurality of water vessels and formed by stacking them like blocks. Such radiation shields can exhibit the effect at the maximum by applying them to an electron beam irradiation device and the like for temporary use. (I.S.)

Iwasaki, Keiko; Katsuki, Kenji

1997-11-28

122

Pencil-shaped radiation detection ionization chamber  

International Nuclear Information System (INIS)

A radiation detection ionization chamber is described. It consists of an elongated cylindrical pencil-shaped tubing forming an outer wall of the chamber and a center electrode disposed along the major axis of the tubing. The length of the chamber is substantially greater than the diameter. A cable connecting portion at one end of the chamber is provided for connecting the chamber to a triaxial cable. An end support portion is connected at the other end of the chamber for supporting and tensioning the center electrode. 17 claims.

1979-01-01

123

Detection of radiation processing in onions  

International Nuclear Information System (INIS)

[en] Two breeds of onions were used for irradiation. Both breeds were divided into two parts - the first was irradiated with a dose of 80 Gy and the second served as a control. The two parts were stored under the same conditions. Conductometry, liquid chromatography and spectrophotometry were used for detecting the radiation processing of the onions. Only from the spectrophotometric determination of 2-desoxysaccharides it was possible to safely distinguish irradiated onions from non-irradiated controls throughout storage time. (E.S.)

1984-11-01

124

Method for detecting biological toxins  

Energy Technology Data Exchange (ETDEWEB)

Biological toxins are indirectly detected by using polymerase chain reaction to amplify unique nucleic acid sequences coding for the toxins or enzymes unique to toxin synthesis. Buffer, primers coding for the unique nucleic acid sequences and an amplifying enzyme are added to a sample suspected of containing the toxin. The mixture is then cycled thermally to exponentially amplify any of these unique nucleic acid sequences present in the sample. The amplified sequences can be detected by various means, including fluorescence. Detection of the amplified sequences is indicative of the presence of toxin in the original sample. By using more than one set of labeled primers, the method can be used to simultaneously detect several toxins in a sample.

Ligler, F.S.; Campbell, J.R.

1992-01-01

125

Dosimetry methods for the estimation of exposure to ionizing radiation  

International Nuclear Information System (INIS)

Ionizing radiations, by their nature, have required for their detection the use of suitable devices generically referred detecting systems. The detection of secondary particles arising during the processes of ionization and excitation to the passage of radiation in the environment, have constituted the basis of the measurement methods. A detector system is a device that converts the energy of the incident radiation on a signal (electrical, photochemical, etc.) that is easily processable from the technological point of view, but without distorting the original information. These devices have provided qualitative or quantitative information about the radiation of interest. The detector system is a set of a detector together with a processing system. This system has based its operation in methods of: gas ionization, scintillation, semiconductor, film, thermoluminescence, among others. (author)

2012-01-01

126

Detection of transient species in radiation chemistry  

International Nuclear Information System (INIS)

Intense energetic electron pulses can be used to produce substantial quantities of transient species in condensed phase radiolysis. Pulsed electron beams have considerable flux advantage over a typical laser photon pulse. The time frame of various events in radiolysis requires a range of time-resolution capabilities in the detection instrumentation, and the information content and spectral resolution of various techniques differ. Restricting our attention to the condensed phase, we will outline fast detection methods that can be used to detect (1) emission: streak cameras and fast photomultipliers; (2) absorption: pulse probe methods using Cherenkov and fast digitizers; (3) conductivity DC and microwave, and (4) three magnetic resonance methods: time-resolved EPR, time-resolved optically detected magnetic resonance, and time-resolved NMR detection of nuclear resonance. Utilizing the above techniques, we can study very short-lived ions, radicals and excited states in both radiolysis and in photoionization. One finds many parallels in the chemistry of transient species in the high-energy regime where the energy input into the condensed phase is more than sufficient to cause ionization. The future challenge is to develop novel detection methods in order to allow significant advances in real time capabilities of radiolytic experiments made possible by the next generation of accelerators

1995-01-01

127

Promising coal interface detection methods  

Energy Technology Data Exchange (ETDEWEB)

One critical element of the US Bureau of Mines computer-assisted mining research program is the development of a reliable coal interface detection (CID) system. Several promising CID concepts currently being investigated by the Bureau include natural gamma radiation (NGR), vibration and passive infrared. To help establish which CID sensor technologies need to be developed for a given seam, coal and adjacent rock samples (immediate roof and floor) are being collected from selected major coal seams in the US and are being analyzed in terms of NGR and other geophysical measurements. This paper provides a brief overview of the Bureau's work in these CID areas. 13 refs., 4 figs., 2 tabs.

Mowrey, G.L. (Bureau of Mines, Pittsburgh, PA (USA). Pittsburgh Research Center)

1991-01-01

128

Detecting transition radiation from a magnetic moment  

CERN Multimedia

Electromagnetic radiation can be emitted not only by particles' charges but also by magnetic moments and higher electric and magnetic multipoles. However experimental proofs of this fundamental fact are extremely scarce. In particular, the magnetic moment contribution has never been observed in any form of polarization radiation. Here, we propose to detect it using vortex electrons carrying large orbital angular momentum (OAM) $\\ell$. The relative contribution of the OAM-induced magnetic moment, $\\ell \\hbar \\omega/E_e$, becomes much larger than the spin-induced contribution $\\hbar \\omega/E_e$, and it can be observed experimentally. As a particular example, we consider transition radiation from vortex electrons obliquely indicent on a boundary between vacuum and a dispersive medium, in which the magnetic moment contribution manifests itself via angular asymmetry. For electrons with $E_e = 300$ keV and $\\ell = 100-1000$ we predict asymmetry of order 0.1%-1%, which could be measurable with existing technology. T...

Ivanov, Igor P

2013-01-01

129

METHOD OF PARASITARY CONTAMINATION DETECTION  

UK PubMed Central (United Kingdom)

FIELD: medicine. ^ SUBSTANCE: invention concerns sanitary parasitology and can be applied in sanitary epidemiological monitoring and environment protection. Method of parasitary contamination detection involves parasitary object flushing off surface, flush concentration, removal of impurities from parasitary objects, analysis preparation obtainment, identification and counting of parasitary objects. Parasitary object flushing off surface is performed by pump-induced intense flow of detergent solution, and concentration is performed by multiple pumping detergent solution through powder filtering device. ^ EFFECT: faster and more accurate detection of parasitary contamination on surface of various objects. ^ 3 cl, 1 dwg

GUZEEVA TAT JANA MIKHAJLOVNA

130

Management of the baseline shift using a new and simple method for respiratory-gated radiation therapy: Detectability and effectiveness of a flexible monitoring system  

International Nuclear Information System (INIS)

Purpose: In respiratory-gated radiation therapy, a baseline shift decreases the accuracy of target coverage and organs at risk (OAR) sparing. The effectiveness of audio-feedback and audio-visual feedback in correcting the baseline shift in the breathing pattern of the patient has been demonstrated previously. However, the baseline shift derived from the intrafraction motion of the patient's body cannot be corrected by these methods. In the present study, the authors designed and developed a simple and flexible system. Methods: The system consisted of a web camera and a computer running our in-house software. The in-house software was adapted to template matching and also to no preimage processing. The system was capable of monitoring the baseline shift in the intrafraction motion of the patient's body. Another marker box was used to monitor the baseline shift due to the flexible setups required of a marker box for gated signals. The system accuracy was evaluated by employing a respiratory motion phantom and was found to be within AAPM Task Group 142 tolerance (positional accuracy

1638-01-00

131

Survey of Anomaly Detection Methods  

Energy Technology Data Exchange (ETDEWEB)

This survey defines the problem of anomaly detection and provides an overview of existing methods. The methods are categorized into two general classes: generative and discriminative. A generative approach involves building a model that represents the joint distribution of the input features and the output labels of system behavior (e.g., normal or anomalous) then applies the model to formulate a decision rule for detecting anomalies. On the other hand, a discriminative approach aims directly to find the decision rule, with the smallest error rate, that distinguishes between normal and anomalous behavior. For each approach, we will give an overview of popular techniques and provide references to state-of-the-art applications.

Ng, B

2006-10-12

132

Method for detecting underground conditions  

Energy Technology Data Exchange (ETDEWEB)

Disclosed is a method for detecting the flame front during the in-situ combustion of a subterranean carbonaceous stratum. This involves providing one or more radio transmitters below the surface of the ground. Each of said transmitters is capable of sensing and transmitting information concerning the physical and chemical properties of its surroundings, and monitoring said transmissions as an indication of the extent and movement of said flame front. Also disclosed is a method for detecting non-uniform packing characteristics of rubblized material which involves providing one or more radio transmitters within the boundaries of a retort capable of sensing and transmitting information concerning the physical parameters of its surroundings, and monitoring said transmissions as an indication of the size and density distributions of the rubble in said retort.

Mccollum, J.D.

1981-05-12

133

Method for detecting underground conditions  

Energy Technology Data Exchange (ETDEWEB)

Disclosed is a method for detecting the flame front during the in situ combustion of a subterranean carbonaceous stratum which involves providing one or more radio transmitters below the surface of the ground. Each of said transmitters is capable of sensing and transmitting information concerning the physical and chemical properties of its surroundings, and monitoring said transmissions as an indication of the extent and movement of said flame front. Also disclosed is a method for detecting non-uniform packing characteristics of rubblized material which involves providing one or more radio transmitters within the boundaries of a retort capable of sensing and transmitting information concerning the physical parameters of its surroundings, and monitoring said transmissions as an indication of the size and density distributions of the rubble in said retort.

Mccollum, J.D.

1980-04-22

134

Methods for detecting bioactive compounds  

UK PubMed Central (United Kingdom)

Methods of detecting bioactive compounds include exposing compounds to one or more classes of chromatophores and measuring or sensing associated changes in one or more of the chromatophores. Representative methods permit identification and quantification of neurotransmitters, toxins, hormones, and chemical warfare agents with or without prior knowledge of the content of a sample. In some examples, chromatophores based on Betta fish are used. Cytosensor apparatus using such chromatophores include means for exposing chromatophores to a sample and optical detection systems for assessing changes in chromatophore optical properties. Compounds can be identified or quantified based on a red-green-blue or hue saturation-value representations of transmitted or reflected light or based on other characterizations of transmitted or reflected light.

CHAPLEN FRANK W. R; GERWICK WILLIAM H; JOVANOVIC GORAN; KOLODZIEJ WOJTEK; LIBURDY JIM; MCFADDEN PHIL; PAUL BRIAN KEVIN; PLANT THOMAS K; TREMPY JANINE E; WILLARD CORWIN

135

Aerial Radiation Detection Vehicle Manned and Unmanned Concepts  

International Nuclear Information System (INIS)

We are developing an Unmanned Aerial Radiation Detection Vehicle that will give new abilities to the Manned Aerial Radiation Detection Vehicle, Air-Ram. A comparison between the two systems will be given, and a report to our first Unmanned Aerial Radiation Detection Vehicle flight. Air-Ram The Air-Ram system, figure 1, has been developed to measure and display online radiation level measurements taken above the radiation area with a chopper. The detected radiation levels are presented on a topographical map with the flight path colored with the radiation intensities. The air crew and controllers on the ground are updated every two seconds. It enables first responders to complete and real time picture of a radiological event which is essential in order to be able to activate and direct ground operations if necessary. The system measures radiation levels and produces a spectrum graph used to identify the isotopes.

2008-02-19

136

Landmine detection by neutron methods  

International Nuclear Information System (INIS)

[en] The development of the novel nuclear methods in the field of landmine identification requires a more precise knowledge of microscopic and macroscopic atomic and nuclear data. In addition, the effect of the weight and density of the explosives on the observation of the anomaly in a dry sand environment was examined by different dummy landmines using a hand-held neutron thermalization detector. The concept of the backscattering spectrometry and its possible use for landmine detection are also discussed. (author)

2004-01-01

137

Method of lightening radiation darkened optical elements  

Energy Technology Data Exchange (ETDEWEB)

A method of lightening a radiation-darkened optical element in wich visible optical energy or electromagnetic radiation having a wavelength in the range of from about 2000 to about 20,000 angstroms is directed into the radiation-darkened optical element; the method may be used to lighten radiation-darkened optical element in-situ during the use of the optical element to transmit data by electronically separating the optical energy from the optical output by frequency filtering, data cooling, or interlacing the optic energy between data intervals.

Reich, Frederich R. (Richland, WA); Schwankoff, Albert R. (W. Richland, WA)

1980-01-01

138

Method of detecting irradiated pepper  

International Nuclear Information System (INIS)

Spices represented by pepper are generally contaminated by microorganisms, and for using them as foodstuffs, some sterilizing treatment is indispensable. However, heating is not suitable to spices, accordingly ethylene oxide gas sterilization has been inevitably carried out, but its carcinogenic property is a problem. Food irradiation is the technology for killing microorganisms and noxious insects which cause the rotting and spoiling of foods and preventing the germination, which is an energy-conserving method without the fear of residual chemicals, therefore, it is most suitable to the sterilization of spices. In the irradiation of lower than 10 kGy, the toxicity test is not required for any food, and the irradiation of spices is permitted in 20 countries. However, in order to establish the international distribution organization for irradiated foods, the PR to consumers and the development of the means of detecting irradiation are the important subjects. The authors used pepper, and examined whether the hydrogen generated by irradiation remains in seeds and it can be detected or not. The experimental method and the results are reported. From the samples without irradiation, hydrogen was scarcely detected. The quantity of hydrogen generated was proportional to dose. The measuring instrument is only a gas chromatograph. (K.I.)

1989-01-01

139

Apparatus and method for detecting tumors  

Energy Technology Data Exchange (ETDEWEB)

A device and method for the detection of tumors in human and animal tissue using transmission or reflection of nonionizing radiation, in particular, visible light having a wavelength most advantageously in the range of 400 to about 700 nanometers, and infrared light having a wavelength in the range of 700 nanometers to about 4 microns (4000 nanometers). Measurement of the amount of absorption and scatter in regions of the tissue involved is in a scanning mode to produce a shadowgraph image using either single wavelength grey scale or preferably multispectral multiple wavelength false color imaging techniques. The apparatus and method also advantageously can be used in conjunction with computer image reconstruction similar to that employed in computerized axial tomography of the type used in X-ray diagnostic techniques. In one of its more advantageous aspects, the apparatus and method are used to differentiate between benign and malignant human breast tumors.

Carroll, R.

1985-05-07

140

Radiation detector arrangements and methods  

International Nuclear Information System (INIS)

[en] The patent describes a radiation detector arrangement. It comprises at least one detector element in the form of a temperature-sensitive resistor whose electrical resistance changes in response to radiation incident on the detector element, the resistor having a high positive temperature coefficient of electrical resistance at a transition in its electrical conductance, circuit means for applying a voltage across the resistor during operation of the detector arrangement, and temperature-regulation means for regulating the temperature of the resistor so as to operate the resistor in the transition, characterised in that the temperature-regulation means comprises the resistor and the circuit means which passes sufficient current through the resistor by resistance heating to a position in the transition at which a further increase in its temperature in response to incident radiation reduces the resistance heating by reducing the current, thereby stabilizing the temperature of the resistor at the position. The positive temperature coefficient at the position being sufficiently high that the change in the resistance heating produced by a change in the temperature of the resistor at the position is larger than a change in power of the incident radiation required to produce that same change in temperature of the resistor in the absence of any change in resistance heating

1988-07-26

 
 
 
 
141

Method for detecting toxic gases  

Energy Technology Data Exchange (ETDEWEB)

A method capable of detecting low concentrations of a pollutant or other component in air or other gas, utilizing a combination of a heating filament having a catalytic surface of a noble metal for exposure to the gas and producing a derivative chemical product from the component, and an electrochemical sensor responsive to the derivative chemical product for providing a signal indicative of the product. At concentrations in the order of about 1-100 ppm of tetrachloroethylene, neither the heating filament nor the electrochemical sensor is individually capable of sensing the pollutant. In the combination, the heating filament converts the benzyl chloride to one or more derivative chemical products which may be detected by the electrochemical sensor.

Stetter, Joseph R. (Naperville, IL); Zaromb, Solomon (Hinsdale, IL); Findlay, Jr., Melvin W. (Bolingbrook, IL)

1991-01-01

142

Electromagnetic Methods of Lightning Detection  

Science.gov (United States)

Both cloud-to-ground and cloud lightning discharges involve a number of processes that produce electromagnetic field signatures in different regions of the spectrum. Salient characteristics of measured wideband electric and magnetic fields generated by various lightning processes at distances ranging from tens to a few hundreds of kilometers (when at least the initial part of the signal is essentially radiation while being not influenced by ionospheric reflections) are reviewed. An overview of the various lightning locating techniques, including magnetic direction finding, time-of-arrival technique, and interferometry, is given. Lightning location on global scale, when radio-frequency electromagnetic signals are dominated by ionospheric reflections, is also considered. Lightning locating system performance characteristics, including flash and stroke detection efficiencies, percentage of misclassified events, location accuracy, and peak current estimation errors, are discussed. Both cloud and cloud-to-ground flashes are considered. Representative examples of modern lightning locating systems are reviewed. Besides general characterization of each system, the available information on its performance characteristics is given with emphasis on those based on formal ground-truth studies published in the peer-reviewed literature.

Rakov, V. A.

2013-08-01

143

Radiation detection technique on the fishery foods  

International Nuclear Information System (INIS)

Recently irradiation of fishery products such as sea bream, lobster etc has been spreading in South-east Asia. It is thus necessary to establish a detection technique for irradiated foods . This study aimed to investigate the effects of irradiation on the production of tyrosine isomers with relation to the status of food sample (frozen and cold-storage) and also the stabilities of the isomers in frozen foods after irradiation. Production of tyrosin isomers (meta-tyrosine, ortho-tyrosine) due to ?-ray irradiation (5 kGy) were observed in the muscles of frozen prawns as well as those at room temperature and the contents of these isomers after the irradiation was not different between the two states of the sample. The content increased depending on the radiation dose. The contents of these tyrosine isomers were not changed after storage at -20degC for 120 days. Therefore, it was thought that the tyrosine isomers were available as an effective indicator for detection of an irradiated food. (M.N.)

1999-01-01

144

Method for detecting Helicobacter pylori  

UK PubMed Central (United Kingdom)

A system and method for detecting bacterial infections in the gastrointestinal tract is disclosed. The system includes a carrier having a first well and a second well. A first composition is disposed in the first well and contains urea in powdered form. A second composition is disposed in a second well and contains an indicator. A biopsy of a gastric sample is manipulated with a specimen-handling tool and is first contacted with the first composition and then placed in the second composition. The second composition indicates the presence of an enzyme, which, in turn, indicates the presence of bacteria.

MCMICHAEL DONALD J; PETERSON KRISTY; MARSHALL BARRY J; MENDIS ARUNI H. W; CHAIRMAN SIMON

145

Statistical methods in radiation physics  

CERN Multimedia

This statistics textbook, with particular emphasis on radiation protection and dosimetry, deals with statistical solutions to problems inherent in health physics measurements and decision making. The authors begin with a description of our current understanding of the statistical nature of physical processes at the atomic level, including radioactive decay and interactions of radiation with matter. Examples are taken from problems encountered in health physics, and the material is presented such that health physicists and most other nuclear professionals will more readily understand the application of statistical principles in the familiar context of the examples. Problems are presented at the end of each chapter, with solutions to selected problems provided online. In addition, numerous worked examples are included throughout the text.

Turner, James E; Bogard, James S

146

A method for testing scattered radiation grids.  

UK PubMed Central (United Kingdom)

A simple method of evaluating contrast improvement factors and other related quantities has been developed. With this method a water or lucite phantom is imaged with a lead disk on a nonscreen film using a scattered radiation grid with unknown characteristics. The image is then compared with that obtained with the same arrangement but with a calibrated scattered radiation grid. The method described does not need sophisticated instruments and can be used in any department of diagnostic radiology

Nielsen B

1980-03-01

147

METHOD AND APPARATUS FOR RADIATION RESISTANT IMAGING  

UK PubMed Central (United Kingdom)

The present invention pertains to an apparatus and method for radiation resistant medical imaging. A scanning beam x-ray source and x-ray detector are used. A detector shield is utilized to shield the x-ray detector from radiation.

WILFLEY BRIAN PATRICK; SOLOMON EDWARD GERALD; HEANUE JOSEPH ANTHONY

148

System and method for administering radiation  

International Nuclear Information System (INIS)

A system and method for metering the quantity of radiation administered a subject by a source of radiation movable along a path relative to the subject is described. The system cumulatively counts the amount of radiation directed toward the subject during each of a succession of increments of motion of the source. When a predetermined amount of radiation is delivered during an increment, the source is disabled until the source passes into the next increment of displacement. The count of radiation is restarted at the instant the source is disabled, to accumulate accurately any added spurious radiation dosage which may occur and to include that dosage in the count of the permitted amount for the next succeeding increment of motion. Several interlocks for disabling the system in response to various malfunctions are included. Means for controlling the speed of movement of the source and/or the dose rate of the source are also included. (auth)

1975-01-01

149

Frenet-Serret vacuum radiation, detection proposals and related topics  

CERN Document Server

The paradigmatic Unruh radiation is an ideal and simple case of stationary vacuum radiation patterns related to worldlines defined as Frenet-Serret curves. We review the corresponding body of literature as well as the experimental proposals that have been suggested to detect these types of quantum field radiation patterns. Finally, we comment on a few other topics related to the Unruh effect

Rosu, H C

2003-01-01

150

Multi-spectral schottky barrier infrared radiation detection array  

Energy Technology Data Exchange (ETDEWEB)

A multi-spectral Schottky barrier infrared detector array in which individual pixels of radiation from a remote radiating object are detected by two or more Schottky barrier infrared radiation detectors each having a different spectral response so as to provide a ''color'' discrimination for the array.

Foss, N.A.

1983-12-27

151

Multi-spectral schottky barrier infrared radiation detection array  

International Nuclear Information System (INIS)

[en] A multi-spectral Schottky barrier infrared detector array in which individual pixels of radiation from a remote radiating object are detected by two or more Schottky barrier infrared radiation detectors each having a different spectral response so as to provide a ''color'' discrimination for the array

1983-01-01

152

Small Teleoperated Robot for Nuclear Radiation and Chemical Leak Detection  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In order to meet the actual requirements of nuclear radiation and chemical leak detection, and emergency response, a new small teleoperated robot for nuclear radiation and chemical detection is proposed. A small?size robot is manufactured according to technical requirements and the overall structure...

Kui Qian; Aiguo Song; Jiatong Bao; Huatao Zhang

153

Moment Method Solution to Spiral Antenna Radiation.  

Science.gov (United States)

The method of moments provides a general approach for obtaining an approximate solution to the radiation pattern of a logarithmic spiral antenna. This solution is obtained via a knowledge of the current distribution induced on the antenna by feed excitati...

P. Skinner A. J. Terzuoli

1985-01-01

154

The Matrix Element Method and QCD Radiation  

CERN Multimedia

The matrix element method (MEM) has been extensively used for the analysis of top-quark and W-boson physics at the Tevatron, but without dedicated treatment of initial state QCD radiation. At the LHC, the increased center of mass energy leads to a significant increase in the amount of QCD radiation, which makes it mandatory to carefully account for its effects. We here present several methods for inclusion of QCD radiation effects in the MEM, and apply them to mass determination in the presence of multiple invisible particles in the final state. We demonstrate significantly improved results compared to the standard treatment.

Alwall, J; Mattelaer, O

2010-01-01

155

85Kr detection by Cherenkov radiation measurement  

International Nuclear Information System (INIS)

[en] Using a Packard liquid scintillation spectrometer, experiments were done to examine the possibility of determining 85Kr by Cherenkov counting in toluene. The test gas was a mixture (0.1 - 1 cm3) of 85Kr, N2 and air with a maximum activity concentration of 1010 Bq.m-3. The method proved to be suitable for the quantitative analysis of 85Kr, provided the effect of other radionuclides can be neglected. For a counting time of 6000 sec the lower limit of detection was determined as 0.8 Bq (2? level). (author)

1982-01-01

156

Explosives detection using resonance fluorescence of bremsstrahlung radiation  

Energy Technology Data Exchange (ETDEWEB)

This patent describes a method for detecting explosive materials in a target, the explosive materials containing characteristically large or small amounts of one or more nuclear species of interest. It comprises resonantly exciting nuclei of the target with a beam of bremsstrahlung radiation, resonantly exciting nuclei of one or more reference scatterers with the beam of bremsstrahlung radiation transmitted through the target, each the reference scatterer comprising one or more of the nuclear species of interest, measuring the intensity of photons at energies of interest scattered from each the reference scatterer in a direction or directions, the energies of interest for each reference scatterer corresponding to the spacings between the quantized energy states of the nuclear species of interest of which the reference scatterer is comprised, and estimating the abundance of each nuclear species of interest in the target from the measured intensity of photons scattered from the reference scatterer or scatterers comprising the nuclear species.

Bertozzi, W.

1992-05-19

157

Detection of radiation treatment of beans using DNA comet assay  

Energy Technology Data Exchange (ETDEWEB)

A simple technique of microgel electrophoresis of single cells (DNA Comet Assay) enabled a quick detection of radiation treatment of several kinds of leguminous beans (azuki, black, black eye, mung, pinto, red kidney and white beans). Each variety was exposed to radiation doses of 0.5, 1 and 5 kGy covering the permissible limits for insect disinfestation. The cells or nuclei from beans were extracted in cold PBS, embedded in agarose on microscope slides, lysed between 15 and 60 min in 2.5% SDS and electrophoresis was carried out at a voltage of 2 V/cm for 2-2.5 min. After silver staining, the slides were evaluated through an ordinary transmission microscope. In irradiated samples, fragmented DNA stretched towards the anode and the damaged cells appeared as a comet. The density of DNA in the tails increased with increasing radiation dose. However, in non-irradiated samples, the large molecules of DNA remained relatively intact and there was only minor or no migration of DNA; the cells were round or had very short tails only. Hence, the DNA comet assay provides an inexpensive, rapid and relatively simple screening method for the detection of irradiated beans.

Khan, Ashfaq A.; Khan, Hasan M. E-mail: hmkhan@upesh.eduhmkhan_pk@yahoo.com; Delincee, Henry

2002-03-01

158

Detection methods for irradiated mites and insects  

International Nuclear Information System (INIS)

Results of the study on the following tests for separation of irradiated pests from untreated ones are reported: (a) test for identification of irradiated mites (Acaridae) based on lack of fecundity of treated females; (b) test for identification of irradiated beetles based on their locomotor activity; (c) test for identification of irradiated pests based on electron spin resonance (ESR) signal derived from treated insects; (d) test for identification of irradiated pests based on changes in the midgut induced by gamma radiation; and (e) test for identification of irradiated pests based on the alterations in total proteins of treated adults. Of these detection methods, only the test based on the pathological changes induced by irradiation in the insect midgut may identify consistently either irradiated larvae or adults. This test is simple and convenient when a rapid processing technique for dehydrating and embedding the midgut is used. (author)

1999-01-01

159

Tungsten balls charge method radiation shield system  

International Nuclear Information System (INIS)

In the outage at nuclear power plant, we try to reduce radiation exposure by installing shields in the work at places of high radiation dose rate. Many of these shields consist of the sheets and plates of heavy metals, and it takes a longer time to install or remove them because heavy loads must be accompanied. At our company, therefore, we have developed a tungsten balls charge method radiation shield system, can reduce the exposure and workload of its installation/removal. We will further promote various advanced techniques including Tungsten balls shielding technique to flexibly meet needs of operating plants. (author)

2010-01-01

160

Methods of in vivo radiation measurement  

Energy Technology Data Exchange (ETDEWEB)

Methods of and apparatus for in vivo radiation measurements relay on a MOSFET dosimeter of high radiation sensitivity with operates in both the passive mode to provide an integrated dose detector and active mode to provide an irradiation rate detector. A compensating circuit with a matched unirradiated MOSFET is provided to operate at a current designed to eliminate temperature dependence of the device. Preferably, the MOSFET is rigidly mounted in the end of a miniature catheter and the catheter is implanted in the patient proximate the radiation source.

Huffman, Dennis D. (Albuquerque, NM); Hughes, Robert C. (Albuquerque, NM); Kelsey, Charles A. (Albuquerque, NM); Lane, Richard (Galveston, TX); Ricco, Antonio J. (Albuquerque, NM); Snelling, Jay B. (Albuquerque, NM); Zipperian, Thomas E. (Albuquerque, NM)

1990-01-01

 
 
 
 
161

Measuring methods for whole beta radiations  

International Nuclear Information System (INIS)

It is necessary to know rapidly the outline information on environmental radiation depending on the conditions of releasing radioactive material into environment or the purposes of measuring them. Whole beta radiation measurement is used for this purpose. In other words, though nuclides are not identified, approximate radioactive decay is determined. The factors affecting the results of the whole beta radiation measurement include the proportion of beta emission of samples, continuity of energy spectra of beta ray, selection of calibration sources, selection and characteristics of measuring instruments, and self absorption by the samples. The maximum disturbance for detecting artificial radiations is the contribution of natural radioactivity contained in samples, though a part of the above factors is improved by correction. Since estimation of the disturbance so far involved comparatively large error, the whole beta radiation is expressed in a form of including the contribution of natural radioactivity. Though there are many factors for making the results uncertain, the whole beta radiation measurement offers still useful result. However, it is not suitable in case of soft ? nuclides such as tritium and 14C are dominant. The contents are divided into nine chapters including introduction, measurement criteria, rain and dust, sea water, land water, crops, milk, soil and sea bottom sediments, and marine organisms. This manual is the revised third edition, and the revised parts are summarized in appendix 1. (Wakatsuki, Y.)

1977-01-01

162

Method of failed fuel detection  

International Nuclear Information System (INIS)

[en] A method for accurately detecting flaws in a fuel element which need not be removed from its surrounding radioactive environment comprises forming a replica of the element which is then visually inspected for damage. A material hardenable at normal temperatures such as silicon rubber is coated on the inner side of an arcuate supporter which is inserted within the radioactive environment by means of a manipulator and tightly applied to the surface of the failed element in the vicinity of the flaw. Upon hardening of the coating material the supporter is removed and the coating is peeled off, extracted from the radioactive environment and cleaned for removal of radioactivity, thus enabling it to be directly handled. The hardened coating bearing a reverse impression of the flawed fuel element surface is then employed as a mold to produce an exact flaw replica which may be safely handled and inspected. It is therefore possible to directly and safely inspect the flaws in damaged fuel elements while they are still confined within a reactor or hot cell without relying upon periscopes, boroscopes or stereoscopes. (Owens, K. J.)

1970-01-01

163

Feasibility of fiber-optic radiation sensor using Cerenkov effect for detecting thermal neutrons.  

UK PubMed Central (United Kingdom)

In this research, we propose a novel method for detecting thermal neutrons with a fiber-optic radiation sensor using the Cerenkov effect. We fabricate a fiber-optic radiation sensor that detects thermal neutrons with a Gd-foil, a rutile crystal, and a plastic optical fiber. The relationship between the fluxes of electrons inducing Cerenkov radiation in the sensor probe of the fiber-optic radiation sensor and thermal neutron fluxes is determined using the Monte Carlo N-particle transport code simulations. To evaluate the fiber-optic radiation sensor, the Cerenkov radiation generated in the fiber-optic radiation sensor by irradiation of pure thermal neutron beams is measured according to the depths of polyethylene.

Jang KW; Yagi T; Pyeon CH; Yoo WJ; Shin SH; Misawa T; Lee B

2013-06-01

164

Radiation and Nuclear Materials Detection Research and Development at ORNL  

Energy Technology Data Exchange (ETDEWEB)

Research and development is underway to improve radiation and nuclear detection capabilities. This research and development in radiation and nuclear detection includes areas such as advanced materials, applied research and engineering for designing and fabricating customized detection equipment, and theoretical modeling and computational support. Oak Ridge National Laboratory (ORNL) has a distinctive set of detector materials fabrication and characterization capabilities and recently created a Center for Radiation Detection Materials and Systems. Applied research and engineering efforts have led to the development of improved detectors for specific applications including safeguards, treaty monitoring, and science experiments. All sizes, types, and capabilities of detector systems have been addressed from miniature to man-portable and from neutrons to gamma radiation. Dedicated test beds, in-house and in the field, have been established to analyze, characterize, and improve detection systems.

Hardy, Jim E [ORNL; Wright, Michael C [ORNL

2009-01-01

165

Detection of radiation-induced changes in electrochemical properties of austenitic stainless steels using miniaturized specimens and the single-loop electrochemical potentiokinetic reactivation method  

Energy Technology Data Exchange (ETDEWEB)

Single-loop electrochemical potentiokinetic reactivation testing of miniaturized (TEM) specimens can provide reliable data comparable to data obtained with larger specimens. Significant changes in electrochemical properties (increased reactivation current and Flade potential) were detected for PCA and type 316 stainless steels irradiated at 200--420{degrees}C up to 7--9 dpa. Irradiations in the FFTF Materials Open Test Assembly and in the Oak Ridge Research Reactor are reported on. 45 figs., 5 tabs., 52 refs.

Inazumi, T.; Bell, G.E.C.; Kenik, E.A.; Kiuchi, K.

1993-01-01

166

Detection of radiation-induced changes in electrochemical properties of austenitic stainless steels using miniaturized specimens and the single-loop electrochemical potentiokinetic reactivation method  

Energy Technology Data Exchange (ETDEWEB)

Single-loop electrochemical potentiokinetic reactivation testing of miniaturized (TEM) specimens can provide reliable data comparable to data obtained with larger specimens. Significant changes in electrochemical properties (increased reactivation current and Flade potential) were detected for PCA and type 316 stainless steels irradiated at 200--420[degrees]C up to 7--9 dpa. Irradiations in the FFTF Materials Open Test Assembly and in the Oak Ridge Research Reactor are reported on. 45 figs., 5 tabs., 52 refs.

Inazumi, T.; Bell, G.E.C.; Kenik, E.A.; Kiuchi, K.

1993-01-01

167

Detection of radiation-induced changes in electrochemical properties of austenitic stainless steels using miniaturized specimens and the single-loop electrochemical potentiokinetic reactivation method  

International Nuclear Information System (INIS)

Single-loop electrochemical potentiokinetic reactivation testing of miniaturized (TEM) specimens can provide reliable data comparable to data obtained with larger specimens. Significant changes in electrochemical properties (increased reactivation current and Flade potential) were detected for PCA and type 316 stainless steels irradiated at 200--420 degrees C up to 7--9 dpa. Irradiations in the FFTF Materials Open Test Assembly and in the Oak Ridge Research Reactor are reported on. 45 figs., 5 tabs., 52 refs

1993-01-01

168

Detection of food irradiation with luminescence methods  

International Nuclear Information System (INIS)

[en] Food irradiation is applied as method for the preservation of foods, the prevention of food spoilage and the inhibition of food-borne pathogens. Doses exceeding 10 kGy (10 kJ/kg) are not recommended by the WHO. The different legislation requires methods for the detection and the closimetry of irradiated foods. Among the physical methods based on the radiation-induced changes in inorganic, nonhygroscopic crystalline solids are thermoluminescence (TL), photostimulated luminescence (PSL) and lyoluminescence (LL) measurement. The luminescence methods were tested on natural minerals. Pure quartz, feldspars, calcite, aragonite and dolomite of known origin were irradiated, read out and analyzed to determine the influence of luminescence-activators and deactivators. Carbonate minerals show an orange-red TL easily detectable by blue-sensitive photomultiplier tubes. TIL-inactive carbonate samples may be identified by a lyoluminescence method using the reaction of trapped irradiation-generated charge carriers with the solvent during crystal-lattice breakup. The fine-ground mineral is dissolved in an alkaline complexing agent/chemiluminescence sensitizer/chemiluminescence catalyst (EDTA/luminol/hemin) reagent mixture. The TL and PSL of quartz is too weak to contribute a significant part for the corresponding signals in polymineral dust. Alkali and soda feldspar show intense TL and PSL. The temperature maxima in the TL glow curves allow a clear distinction. PSL does not give this additional information, it suffers from bleaching by ambient light and requires light-protection. Grain disinfestated with low irradiation doses (500 Gy) may not identified by both TL and PSL measurement. The natural TL of feldspar particles may be overlap with the irradiation-induced TL of other minerals. As a routine method, irradiated spices are identified with TL measurement. The dust particles have to be enriched by heavy-liquid flotation and centrifugation. The PSL method allows a clear identification of irradiated spices. The detection of irradiated seafood (mollusks and crustaceans) with TL is only possible for calcitic shells. The EDTA-luminol lyoluminescence is applicable for both calcitic and aragonitic shells, calcitic, amorphous and partially hydroxyapatitic crustacean molts, and poultry bones. The application of chemical methods is much more susceptible to errors.The high-performance liquid chromatography-determination of ortho- and metatyrosine in low-fat poultry and shrimp meat did not allow any positive identification of irradiated samples. (author)

1997-01-01

169

Ensemble approaches for improving community detection methods  

CERN Document Server

Statistical estimates can often be improved by fusion of data from several different sources. One example is so-called ensemble methods which have been successfully applied in areas such as machine learning for classification and clustering. In this paper, we present an ensemble method to improve community detection by aggregating the information found in an ensemble of community structures. This ensemble can found by re-sampling methods, multiple runs of a stochastic community detection method, or by several different community detection algorithms applied to the same network. The proposed method is evaluated using random networks with community structures and compared with two commonly used community detection methods. The proposed method when applied on a stochastic community detection algorithm performs well with low computational complexity, thus offering both a new approach to community detection and an additional community detection method.

Dahlin, Johan

2013-01-01

170

Method to detect biological particles  

International Nuclear Information System (INIS)

[en] A medical-diagnostic method to detect immunological as well as other specific reactions is described. According to the invention, first reactive particles (e.g. antibodies) are adsorbed on the surface of a solid, non-reactive substrate. The coated substrate is subjected to a solution which one assumes to contain the second biological particles (e.g. antigens) which are specific to the first and form complexes with these. A preferential radioactive labelling (e.g. with iodine 125) of the second biological particle is then directly or indirectly carried out. Clearage follows labelling in order to separate the second biological particles from the first ones. A specific splitting agent can selectively break the bond of both types of particle. The splitting agent solution is finally separated off and its content is investigated for the presence of labelling. (VJ)[de] Ein medizinisch-diagnostisches Verfahren zum Nachweis immunologischer sowie anderer spezifischer Reaktionen wird beschrieben. Gemaess der Erfindung werden an der Oberflaeche eines festen, nicht reaktiven Substrates erste reaktive Teilchen (z.B. Antikoerper) adsorbiert. Das ueberzogene Substrat wird einer Loesung ausgesetzt, von der man annimmt, dass sie die zweiten biologischen Teilchen (z.B. Antigene) enthaelt, die spezifisch zu den ersten sind und mit ihnen komplexieren. Im folgenden wird eine - bevorzugt radioaktive - Markierung (z.B. mit Jod-125) der zweiten biologischen Teilchen direkt oder indirekt vorgenommen. Der Markierung folgt eine Spaltung, um die zweiten biologischen Teilchen von den ersten abzutrennen. Ein spezifisches Spaltmittel kann die Bindung beider Teilchenarten selektiv aufloesen. Die Spaltmittelloesung wird schliesslich abgetrennt und der darin enthaltene Inhalt auf Anwesenheit von Markierungen untersucht. (VJ)

1976-01-01

171

Nonlinear response matrix methods for radiative transfer. [Radiative transfer  

Energy Technology Data Exchange (ETDEWEB)

A nonlinear response matrix formalism is presented for the solution of time-dependent radiative transfer problems. The essential feature of the method is that within each computational cell the temperature is calculated in response to the incoming photons from all frequency groups. Thus the updating of the temperature distribution is placed within the iterative solution of the spaceangle transport problem, instead of being placed outside of it. The method is formulated for both grey and multifrequency problems and applied in slab geometry. The method is compared to the more conventional source iteration technique. 7 refs., 1 fig., 4 tabs.

Miller, W.F. Jr.; Lewis, E.E.

1987-01-01

172

Computational methods for industrial radiation measurement applications  

International Nuclear Information System (INIS)

Computational methods have been used with considerable success to complement radiation measurements in solving a wide range of industrial problems. The almost exponential growth of computer capability and applications in the last few years leads to a open-quotes black boxclose quotes mentality for radiation measurement applications. If a black box is defined as any radiation measurement device that is capable of measuring the parameters of interest when a wide range of operating and sample conditions may occur, then the development of computational methods for industrial radiation measurement applications should now be focused on the black box approach and the deduction of properties of interest from the response with acceptable accuracy and reasonable efficiency. Nowadays, increasingly better understanding of radiation physical processes, more accurate and complete fundamental physical data, and more advanced modeling and software/hardware techniques have made it possible to make giant strides in that direction with new ideas implemented with computer software. The Center for Engineering Applications of Radioisotopes (CEAR) at North Carolina State University has been working on a variety of projects in the area of radiation analyzers and gauges for accomplishing this for quite some time, and they are discussed here with emphasis on current accomplishments.

1996-01-01

173

Computational methods for industrial radiation measurement applications  

Energy Technology Data Exchange (ETDEWEB)

Computational methods have been used with considerable success to complement radiation measurements in solving a wide range of industrial problems. The almost exponential growth of computer capability and applications in the last few years leads to a {open_quotes}black box{close_quotes} mentality for radiation measurement applications. If a black box is defined as any radiation measurement device that is capable of measuring the parameters of interest when a wide range of operating and sample conditions may occur, then the development of computational methods for industrial radiation measurement applications should now be focused on the black box approach and the deduction of properties of interest from the response with acceptable accuracy and reasonable efficiency. Nowadays, increasingly better understanding of radiation physical processes, more accurate and complete fundamental physical data, and more advanced modeling and software/hardware techniques have made it possible to make giant strides in that direction with new ideas implemented with computer software. The Center for Engineering Applications of Radioisotopes (CEAR) at North Carolina State University has been working on a variety of projects in the area of radiation analyzers and gauges for accomplishing this for quite some time, and they are discussed here with emphasis on current accomplishments.

Gardner, R.P.; Guo, P.; Ao, Q. [North Carolina State Univ., Raleigh, NC (United States)

1996-12-31

174

Device for detection of ionizing radiation dose  

International Nuclear Information System (INIS)

The design of a detector is described which consists of an airtight bushing filled with gas under mild underpressure. At one end of the detector there is a window through which passes ionizing radiation. The advantage of the detector claimed is the accuracy of measurement of the dose of a specific ionizing radiation, the simple design and the continuous use of the detector at certain time intervals. (E.S.). 1 fig

1985-07-24

175

Geometric phase shift for detection of gravitational radiation  

CERN Document Server

An effect of geometrical phase shift is predicted for a light beam propagating in the field of a gravitational wave. Gravitational radiation detection experiments are proposed using this new effect, the corresponding estimates being given.

Mitskievich, N V

1996-01-01

176

A New Bilirubin Concentration Detection Method by Light Reflection  

CERN Document Server

A new and simple method of blood bilirubin detection through light reflection from skin is developed. The basic improvement over the existing methods is in the design of the light emitter and detector geometry which facilitates a two-stream plane parallel homogenous medium solution to the emitting-scatterig radiative transfer equation. The forward peak in the scattering phase function that is characteristic of water droplets and water filled media is accounted for through a proper method named delta-Eddington approximation.

Subasilar, B

1999-01-01

177

Physical problems in measuring the blood flow through organs by means of inhalation of noble gases with special regard to three-dimensional methods of radiation detection  

International Nuclear Information System (INIS)

The paper gives a survey of the current indirect methods of blood flow measurement with the aid of radioactive isotopes. Liver, spleen, and kidneys were investigated in order to find out whether noble gas washout may also be carried out by inhalation and external measurement alone, which do not involve any disconfort to the patient. Compartment models were established for different organs, and the conditions of measurement chosen were such that the parameters of blood flow could be determined unambiguously. The problems encountered in liver blood flow determination are mainly due to the human anatomy. The complicated blood flow pattern makes the use of freely diffusible tracers advisable, especially in pathological cases. The values measured in normal livers using the inhalation method are consistent with the values obtained by other direct and indirect methods. In pathological cases, further information is required concerning the fat content of the liver. This information can be provided by means of a biopsy or indirectly by a double Xe/Kr measurement. Up to a fat content of 10% of the moist weight, the error in the blood flow values measured is

1973-01-01

178

Archived BAM Method: Rapid Methods for Detecting ...  

Science.gov (United States)

... Salmonella, Isogrid b, HGMF, QA Labs. OSRT, Medium/ motility, Unipath (Oxoid). Rambach, Medium, CHROMagar. MUCAP, C8esterase, Biolife. ... More results from www.fda.gov/Food/FoodScienceResearch/LaboratoryMethods

179

METHOD OF FABRICATION LIF OPTICAL REACTION CHAMBER TO DETECT TRANSCUTENEOUS PCO2 AND DETECTING SYSTEM THEREOF  

UK PubMed Central (United Kingdom)

A method of fabrication LiF optical reaction chamber to detect transcuteneous pCO2 and detecting system thereof can make the light reaction chamber more fine and simple by using the ductility etching method. The optical source section(100) radiates the middle infrared wavelength. The optical detecting part(300) detects the intensity of the light source of the specific wave reacting to the measurement target gas. The signal processing unit(400) converts the intensity of the light source detected through the optical detecting part into the electric signal. The LiF chamber forms pattern by using the ductility etching method. The bubble is removed under the vacuum atmosphere by diluting PDMS and elastomer.

KANG SHIN WON; KANG BYOUNG HO; KIM DO EOK

180

Compositions and Methods for Detecting Treponema Pallidum.  

Science.gov (United States)

Methods for the specific and highly sensitive detection of Treponema pallidum infection comprising the use of specific antigenic proteins and peptides unique to Treponema pallidum are provided. In particular, detection assays based recognition of acidic r...

B. Rodes B. M. Steiner H. Liu

2001-01-01

 
 
 
 
181

Method of sintering materials with microwave radiation  

Energy Technology Data Exchange (ETDEWEB)

Disclosed is a method of sintering ceramic materials. A compacted article comprising inorganic particles coated with carbon is provided, the carbon providing improved microwave coupling. The compacted article is then heated by microwave radiation to a temperature and for a period of time sufficient to sinter the compacted article. No Drawings

Kimrey, H.D. Jr.; Holcombe, C.E. Jr.; Dykes, N.L.

1994-06-14

182

Method of sintering materials with microwave radiation  

Energy Technology Data Exchange (ETDEWEB)

A method of sintering ceramic materials following: A compacted article comprising inorganic particles coated with carbon is provided, the carbon providing improved microwave coupling. The compacted article is then heated by microwave radiation to a temperature and for a period of time sufficient to sinter the compacted article.

Kimrey, Jr., Harold D. (Knoxville, TN); Holcombe, Jr., Cressie E. (Farragut, TN); Dykes, Norman L. (Oak Ridge, TN)

1994-01-01

183

Numerical Methods for Radiation Magnetohydrodynamics in Astrophysics  

Energy Technology Data Exchange (ETDEWEB)

We describe numerical methods for solving the equations of radiation magnetohydrodynamics (MHD) for astrophysical fluid flow. Such methods are essential for the investigation of the time-dependent and multidimensional dynamics of a variety of astrophysical systems, although our particular interest is motivated by problems in star formation. Over the past few years, the authors have been members of two parallel code development efforts, and this review reflects that organization. In particular, we discuss numerical methods for MHD as implemented in the Athena code, and numerical methods for radiation hydrodynamics as implemented in the Orion code. We discuss the challenges introduced by the use of adaptive mesh refinement in both codes, as well as the most promising directions for future developments.

Klein, R I; Stone, J M

2007-11-20

184

Radiation sources and methods for producing them  

International Nuclear Information System (INIS)

The radiation sources contain a substrate with an electrically conducting, non-radioactive metal surface, a layer of a metal isotope of the scandium group as well as a percentage of non-radioactive binding metal being coated on the surface by means of an electroplating method. Besides examples for ? sources (147Pm), ? sources (241Am), and neutron sources (252Cf) there is described an ?-radiation source (241Am, 244Cu, 238Pu) for smoke detectors. There are given extensive tables and a bibliography. (DG)

1979-01-01

185

Intracavity methods for enhancing laser radiation directivity  

Energy Technology Data Exchange (ETDEWEB)

A systematic review of intracavity methods for improving laser-radiation directivity is presented. Attention is given to methods for the direct improvement of the laser directivity pattern; the prospects of transforming the laser emission into a single-mode beam; and wavefront control. The feasibility of creating solid-state laser with a nearly diffractive directivity at mean powers up to several hundred watts is demonstrated. 28 refs.

Liubimov, V.V.

1990-12-01

186

Method for detecting chlorothalonil pesticide residue and detection kit therefor  

UK PubMed Central (United Kingdom)

The invention relates to a method for detecting ELISA remained in chlorothalonil pesticide and a reagent kit thereof. Glycol is utilized to substitute chloride atoms on 6 position carbon atoms of chlorothalonil molecules to synthesize a semiantigen then an imidazolone method is adopted to link the semiantigen to a carrier, namely bovine serum albumin molecules to form an artificial complete antigen an antigen-immunized rabbit is used to prepare a polyclonal antibody which is assembled with related reagents into an ELISA reagent kit and an ELISA indirect method of antigen-primary antibody-ELIAS secondary antibody is used to detect residues of the chlorothalonil pesticide. The method has the advantages of low cost, high efficiency, and low detection limit the detection of 96 samples at one time can be finished within four hours, and the lowest limit of the detection is 0.016mg.kg<-1>.

LILI ZHANG; HONGJIN BAI; YANQIN WANG; CHUANXING WAN; WENJIE LIU; WEI CHEN; XIAOLIANG ZHAO; BO JING

187

Investigation of detection technique of irradiated food. Detection of irradiated food by TL method  

Energy Technology Data Exchange (ETDEWEB)

Thermo luminescence (TL) method, one of detection method of irradiated food, was applied to black pepper. The inorganic substances such as dust, sand and soil adhered to food can capture irradiation energy and emit it by heat as luminescence. Black pepper of Turkey and Malaysia were irradiated 0.5-10KGy dose from {sup 60}Co radiation source. Although different TL emission curves were observed by the place of production and the particle size of inorganic substance adhered, the strength of emission was constant for a long time. The results proved that this method was a good detection method for irradiated food adhered inorganic substances. (S.Y.)

Tanabe, Hiroko; Hogetsu, Daisuke [Tokyo Metropolitan Isotope Research Center (Japan)

1997-09-01

188

Agenda - Rapid Methods for Detecting Mycoplasma ...  

Science.gov (United States)

... Agenda - Rapid Methods for Detecting Mycoplasma Contamination in the Manufacture of Vaccines, Including Pandemic Influenza Vaccines, and ... More results from www.fda.gov/biologicsbloodvaccines/newsevents/workshopsmeetingsconferences

189

Radiation methods of impregnating wooden cultural objects  

International Nuclear Information System (INIS)

[en] The process was studied of polymerization in wood at low dose rates of gamma radiation. It was demonstrated that at radiation doses below the optimal level of 1.0 kGy.h-1, polymerization in wood decreased significantly. It was found that the molecular weight of polymethyl methacrylate prepared by radiation polymerization in samples of linden tree wood increased with decreasing dose rate and decreased with growing dose. It was also shown that the final size of samples after polymerization was the bigger the higher was the content of polymers in the wood attained. A study of radiation copolymerization of methyl methacrylate with butyl methacrylate in wood showed that the addition of butyl methacrylate in the monomer mixture increased the polymer yield in the wood and reduced moisture expansion of the wood during polymerization. In order to test the possible applications of obtained results a number of experiments were made which showed that the use of radiation polymerization is promising in wood which is not polychromatic. The wood surface following impregnation remained unchanged and restoration could be continued. In case of polychrom wood sculptures the application of the method was promising for tempera and gilding using a dose of less than 40 kGy at a dose rate of 1 kGy/h. In case of polychromatic wood sculptures with addition of oil binders there was the danger of damaging the object. (J.B.). 4 figs., 2 tabs., 2 refs

1988-01-01

190

Method of attenuation of electromagnetic radiation  

Energy Technology Data Exchange (ETDEWEB)

A method for the protection of matter, including humans, by attenuation of electromagnetic radiation comprises providing the matter with a protective layer of an inorganic composition formed from at least two elements, or compounds thereof, selected from different specified groups. The elements provide complementary attenuation of the radiation, and may be selected to optimize protection against specific energy spectra. The inorganic composition may be in a carrier e.g. a polymer. The method may be used in a variety of ways e.g. in protection of humans from x-rays, gamma rays or other radiation, or in packaging applications, protection of equipment sensitive to radiation or the like. The inorganic composition comprises elements or compounds of Ac, Bi, Au, Pb, Hg, Pu, Po, Pa, Tl, Th and/or U together with elements or compounds of Sb, Ba, Cd, Ce, Cs, La, Pb, In, I, Ag, Te, Sn, W, Au, Ir, Hg, Os, Pt, Re, Ta and/or Tl. (author).

Reh, G.P.; Mawdsley, G.E.; Yaffe, M.J.

1990-05-30

191

Smart Surfaces: New Coatings & Paints with Radiation Detection Functionality  

Energy Technology Data Exchange (ETDEWEB)

Paints are being developed and tested that might ultimately be able to detect radiological agents in the environment by incorporating special pigments into an organic polymeric binder that can be applied as a paint or coatings. These paints detect radioactive sources and contaminants with inorganic or organic scintillation or thermo-luminescent pigments, which are selected based upon the radiation ({alpha}, {beta}, {gamma} or n) to be detected, and are shown in Figure 1.

Farmer, J; Choi, J

2007-03-12

192

PCR detection method for quickly detecting large coptotermes formosunus  

UK PubMed Central (United Kingdom)

The invention discloses a PCR detection method for quickly detecting large coptotermes formosunus, which comprises conventional PCR detection and real-time fluorescence PCR detection. The PCR detection method comprises the following steps: preparing a DNA template for a sample to be detected, designing a specific primer and/or a probe, establishing a PCR reaction system for PCR amplification, andobserving, recording and photographing on a gel imaging system. With the advantage of high speed, stability, reliability and sensitivity, the PCR detection method for quickly detecting large coptotermes formosunus is applied to the detection of different-grade samples of large coptotermes formosunus, and lays a foundation for China's coptotermes formosunus class in molecular classification and therapid identification of sibling species. The result of study can be directly applied to the quarantine identification of large coptotermes formosunus in inward and outward plant quarantine, and has important significance to the production safety protection of agriculture and forestry, biological balance maintenance, public health safety insurance in China.

HAIYANG LE; WEIDONG ZHANG; LI LIAO

193

Method of establishing the optimal radiation dose  

UK PubMed Central (United Kingdom)

A method for determining the number of millicuries to be administered to a patient so as to deliver a given centigray (cGy) dose to either the patient's lean body or the patient's total body. The method includes the steps of injecting a radioactive tracer into a patient, determining radiation levels in the whole body, calculating a geometric mean based on the radiation levels, determining the percent-injected activity remaining in the body at each time point, plotting the percent-injected activity versus calculated time from infusion on a log-linear graph, determining the effective half live and the rate of clearance from the log-linear graph, cross-indexing the effective half-life value with the patient's body weight, and multiplying the determined amount of therapeutic millicuries per centigray by the amount of desired centigray to be administered.

WAHL RICHARD L; ZASADNY KENNETH R

194

Sentinel node detection in malignant melanoma patients: radiation safety considerations.  

UK PubMed Central (United Kingdom)

BACKGROUND: The surgical management of malignant melanoma necessitates correct sentinel lymph node localization. The highest reported sensitivities are those of lymphoscintigraphy and intraoperative gamma-probe detection combined with a vital blue dye technique. OBJECTIVE: Control of the radiation doses experienced by surgical personnel untrained in the use of unsealed radioactive materials. METHODS: Sentinel lymph nodes were localized, and biopsies were performed in 25 patients with malignant melanoma. Radiation doses during surgery were determined with energy-compensated silicon pin diode detectors and LiF thermoluminescent ring dosimeters. RESULTS: In 21 cases (24%), the measured doses were less than 1 microSv, but in 4 operations (16%), 1 to 4.5 microSv was received. The equivalent dose rate was generally less than 1 microSv/h. The finger-absorbed doses for the surgeon and the assistant surgeon were (mean+/-SD) 159+/-23 and 48+/-17 microGy per intervention, respectively. CONCLUSION: Personal dosimetric survey and limitation of the number of surgical interventions do not appear to be essential.

Sera T; Mohos G; Papos M; Osvay M; Varga J; Lazar M; Kiss E; Kapitany K; Dobozy A; Csernay L; Pavics L

2003-02-01

195

Methods of measurements on incidental X-radiation from electron tubes  

International Nuclear Information System (INIS)

The standard describes the method for detection of x-radiation and the method for the direct and indirect measurement of field pattern and exposure rate of random incidental radiation emanating from high voltage electron tubes. Required apparatus and calibration procedure for the exposure rate meter or film mount are described. (M.G.B.)

1977-01-01

196

Radiation shielding fiber and its manufacturing method  

International Nuclear Information System (INIS)

Purpose: To manufacture radiation shielding fibers of excellent shielding effects. Method: Fibers containing more than 1 mmol/g of carboxyl groups are bonded with heavy metals, or they are impregnated with an aqueous solution containing water-soluble heavy metal salts dissolved therein. Fibers as the substrate may be any of forms such as short fibers, long fibers, fiber tows, webs, threads, knitting or woven products, non-woven fabrics, etc. It is however necessary that fibers contain more than 1 mmol/g, preferably, from 2 to 7 mmol/g of carboxylic groups. Since heavy metals having radiation shielding performance are bonded to the outer layer of the fibers and the inherent performance of the fibers per se is possessed, excellent radiation shielding performance can be obtained, as well as they can be applied with spinning, knitting or weaving, stitching, etc. thus can be used for secondary fiber products such as clothings, caps, masks, curtains, carpets, cloths, etc. for use in radiation shieldings. (Kamimura, M.)

1987-02-13

197

Radiation shielding fiber and its manufacturing method  

Energy Technology Data Exchange (ETDEWEB)

Purpose: To manufacture radiation shielding fibers of excellent shielding effects. Method: Fibers containing more than 1 mmol/g of carboxyl groups are bonded with heavy metals, or they are impregnated with an aqueous solution containing water-soluble heavy metal salts dissolved therein. Fibers as the substrate may be any of forms such as short fibers, long fibers, fiber tows, webs, threads, knitting or woven products, non-woven fabrics, etc. It is however necessary that fibers contain more than 1 mmol/g, preferably, from 2 to 7 mmol/g of carboxylic groups. Since heavy metals having radiation shielding performance are bonded to the outer layer of the fibers and the inherent performance of the fibers per se is possessed, excellent radiation shielding performance can be obtained, as well as they can be applied with spinning, knitting or weaving, stitching, etc. thus can be used for secondary fiber products such as clothings, caps, masks, curtains, carpets, cloths, etc. for use in radiation shieldings. (Kamimura, M.).

Tanaka, Koji; Ono, Hiroshi.

1988-08-17

198

Development of radiation detection and measurement system - Development of scintillation radiation sensor  

Energy Technology Data Exchange (ETDEWEB)

We have been fabricated CsI(Tl) scintillation crystals and plastic scintillators for radiation-based measuring equipment. CsI (Tl) single crystals doped with thallium as an activator were grown using the Czochralski method. The crystal structure of grown CsI(Tl) was bcc, and it was confirmed that its lattice constant was 4,568 A. The spectral range of luminescence of CsI(Tl) was 350 {approx} 700 nm independent of thallium concentration, and the fast component of the luminescence was decreased with increasing thallium concentration. The energy resolution of CsI(Tl) scintillator doped with 0.1 mole% thallium was about 9% for 137 Cs {gamma}-rays. The relation formula of {gamma}-ray energy versus energy resolution was ln(FWHM%)=-0.705ln({epsilon})+6.75. The radiation damage of CsI(Tl) increased in proportion to thallium concentration and radiation damage of CsI(Tl) increased in proportion to thallium concentration and radiation dosage, and the irradiated crystals were colored reddish. The radiation induced absorption bands appeared around 355, 425, 520 and 555 nm, and their energy level were about 3.50, 2.88, 2.39 and 2.21 eV. Plastic scintillators were fabricated thermal polymerization method. Those were polymerizing at 120 deg. C, during 72 hours, and annealing at 75 deg. C, during 24 hours. When the concentration of 1st solute was 1.5 wt% and concentration of 2nd solute was 0.01 wt%, the characteristics of scintillation were very excellent. Also 3.0 wt% tetraphenyl lead were loaded to improve the detection efficiency of {gamma}-ray. The range of emission spectrum was 400 {approx} 450nm, and the central peak was 415 nm. The radiation damage was not appear under 1*10{sup 3}Gy, but the color of plastic scintillator was changed to brown, over 1*10{sup 4}Gy exposured. 84 refs., 39 figs. (Author)

Kang, Hee Dong; Kim, Wan [Kyungpook National University, Taegu (Korea); Kim, Do Sung [Taegu University, Taegu (Korea)

2000-03-01

199

Development of radiation detection and measurement systems  

Energy Technology Data Exchange (ETDEWEB)

This report contains descriptions on the following six items. The first item is the result of a study on CsI(TI) crystals with their light emitting characteristics and the result of a study on plastic scintillators. The second item is the result of a study on advanced radiation detectors and includes experiments for the effect of using a Compton suppressor with an HPGe detector. For the third item, we describe the results of a design work done using EGS4 for a thickness gauge, a density gauge, and a level gauge. The fourth item contains descriptions on the prototype circuit systems developed for a level gauge, a thickness gauge, and for a survey meter. The fifth part contains the computed tomography algorithm and a prototype scanning system developed for a CT system. As the sixth and the last item, we describe the prototype high precision heat source and the prototype heat-voltage converter which we have designed and fabricated.

Moon, B. S.; Ham, C. S.; Chung, C. E. and others

2000-03-01

200

Developing methods for detecting radioactive scrap  

Energy Technology Data Exchange (ETDEWEB)

During the last 10 years, there have been major developments in radiation detection systems used for catching shielded radioactive sources in scrap metal. The original testing required to determine the extent of the problem and the preliminary designs of the first instruments will be discussed. Present systems available today will be described listing their advantages and disadvantages. In conclusion, the newest developments and state of the art equipment will also be included describing the limits and most appropriate locations for the systems.

Bellian, J.G.; Johnston, J.G. [Norton Industrial Ceramics Corp. Solon, OH (United States)

1995-07-01

 
 
 
 
201

Method of detecting sulfur dioxide  

Energy Technology Data Exchange (ETDEWEB)

(CH.sub.3).sub.3 SiNSO is produced by the reaction of ((CH.sub.3).sub.3 Si).sub.2 NH with SO.sub.2. Also produced in the reaction are ((CH.sub.3).sub.3 Si).sub.2 O and a new solid compound [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ]. Both (CH.sub.3).sub.3 SiNSO and [NH.sub.4 ][(CH.sub.3).sub.3 SiOSO.sub.2 ] have fluorescent properties. The reaction of the subject invention is used in a method of measuring the concentration of SO.sub.2 pollutants in gases. By the method, a sample of gas is bubbled through a solution of ((CH.sub.3).sub.3 Si).sub.2 NH, whereby any SO.sub.2 present in the gas will react to produce the two fluorescent products. The measured fluorescence of these products can then be used to calculate the concentration of SO.sub.2 in the original gas sample. The solid product [NH.sub.4][(CH.sub.3).sub.3 SiOSO.sub.2 ] may be used as a standard in solid state NMR spectroscopy.

Spicer, Leonard D. (Salt Lake City, UT); Bennett, Dennis W. (Clemson, SC); Davis, Jon F. (Salt Lake City, UT)

1985-01-01

202

Spectral analysis method for detecting an element  

Energy Technology Data Exchange (ETDEWEB)

A method for detecting an element is described and which includes the steps of providing a gamma-ray spectrum which has a region of interest which corresponds with a small amount of an element to be detected; providing nonparametric assumptions about a shape of the gamma-ray spectrum in the region of interest, and which would indicate the presence of the element to be detected; and applying a statistical test to the shape of the gamma-ray spectrum based upon the nonparametric assumptions to detect the small amount of the element to be detected.

Blackwood, Larry G [Idaho Falls, ID; Edwards, Andrew J [Idaho Falls, ID; Jewell, James K [Idaho Falls, ID; Reber, Edward L [Idaho Falls, ID; Seabury, Edward H [Idaho Falls, ID

2008-02-12

203

A Fault Detection Method for Reversible Circuits  

Directory of Open Access Journals (Sweden)

Full Text Available This paper represents a redundancy based mechanism for fault detection in reversiblecircuits. In this method reversible circuit has been duplicated for fault detection. This duplication isbased on self complementary feature of reversible circuits. We have used a fully redundant circuitand a comparator for the purpose fault detection. In order to analyze the proposed method, singleand double faults have been investigated in the following four cases: fault tolerant comparator andsingle fault, non-fault tolerant comparator and single fault, fault tolerant comparator and doublefault, non-fault tolerant comparator and double fault. The results show that the proposed techniqueoffers 100%, 83%, 75% and 64% of fault detection respectively.

Maryam Barshan; Somayeh Bahramnejad; Zeinab Kalantary

2011-01-01

204

Simulated performance of a position sensitive radiation detecting system (COCAE)  

CERN Document Server

Extensive simulations of a portable radiation detecting system have been performed in order to explore important performance parameters. The instrument consists of a stack of ten detecting layers made of pixelated Cadmium Telluride (CdTe) crystals. Its aim is to localize and identify radiation sources, by exploiting the Compton imaging technique. In this paper we present performance parameters based on simulation studies. Specifically the ratio of incompletely absorbed photons, the detector's absolute efficiency as well as its energy and angular resolution are evaluated in a wide range of incident photon energies.

Karafasoulis, K; Seferlis, S; Kaissas, I; Lambropoulos, C; Loukas, D; Poritiriadis, C

2011-01-01

205

A Local Method for Detecting Communities  

CERN Multimedia

We propose a novel method of community detection that is computationally inexpensive and possesses physical significance to a member of a social network. This method is unlike many divisive and agglomerative techniques and is local in the sense that a community can be detected within a network without requiring knowledge of the entire network. A global application of this method is also introduced. Several artificial and real-world networks, including the famous Zachary Karate club, are analyzed.

Bagrow, J; Bagrow, Jim; Bollt, Erik

2004-01-01

206

Rapid methods for detection of bacteria  

DEFF Research Database (Denmark)

Traditional methods for detection of bacteria in drinking water e.g. Heterotrophic Plate Counts (HPC) or Most Probable Number (MNP) take 48-72 hours to give the result. New rapid methods for detection of bacteria are needed to protect the consumers against contaminations. Two rapid methods: Measurements of Adosine Triphosphate and BactiQuantTM have shown promising results as new monitoring tools, which gives the result within minutes/hours.

Corfitzen, Charlotte B.; Andersen, B.Ø.

2006-01-01

207

Advances in radiation detection technologies for responders.  

UK PubMed Central (United Kingdom)

The Department of Homeland Security is supporting the development of a large number of standards for first responders. In the area of detection of radioactive and nuclear materials, four new standards (ANSI N42.32, N42.33, N42.34, and N42.35) and their corresponding test and evaluation protocols were developed to meet Department of Homeland Security needs. Testing of the standards and protocols was carried out at the National Institute of Standards and Technology, Oak Ridge National Laboratory, Pacific Northwest National Laboratory, Los Alamos National Laboratory, and Lawrence Livermore National Laboratory.

Unterweger MP; Pibida LS

2005-11-01

208

Development of radiation detection and measurement systems  

International Nuclear Information System (INIS)

[en] This report contains descriptions on the following six items. The first item is the result of a study on CsI(TI) crystals with their light emitting characteristics and the result of a study on plastic scintillators. The second item is the result of a study on advanced radiation detectors and includes experiments for the effect of using a Compton suppressor with an HPGe detector. For the third item, we describe the results of a design work done using EGS4 for a thickness gauge, a density gauge, and a level gauge. The fourth item contains descriptions on the prototype circuit systems developed for a level gauge, a thickness gauge, and for a survey meter. The fifth part contains the computed tomography algorithm and a prototype scanning system developed for a CT system. As the sixth and the last item, we describe the prototype high precision heat source and the prototype heat-voltage converter which we have designed and fabricated

2000-01-01

209

Ionizing radiation source detection by personal TLD  

International Nuclear Information System (INIS)

The Laboratory for personal dosimetry has about 3000 workers under control. The most of them work in medicine. Some institutions, as big health centers, have different ionizing radiation sources. It is usefull to analyze what has been the source of irradiation, special when appears a dosimeter with high dose. Personal dosimetry equipment is Harshaw TLD Reader Model 6600 and dosimeters consist of two chips LiF TLD-100 assembled in bar-coded cards which are wearing in holders with one tissue-equivalent filter (to determine H(10)) and skin-equivalent the other (to determine H(0.07)). The calibration dosimeters have been irradiated in holders by different sources: x-ray (for 80keV and 100keV), 60Co, 90Sr (for different distances from beta source) and foton beem (at radiotherapy accelerator by 6MeV, 10MeV and 18MeV). The dose ratio for two LiF cristals was calculated and represented with graphs. So, it is possible to calculate the ratio H(10)/H(0.07) for a personal TLD and analyze what has been the source of irradiation. Also, there is the calibration for determination the time of irradiation, according to glow curve deconvolution.

2002-01-01

210

Methods and systems for remote detection of gases  

Energy Technology Data Exchange (ETDEWEB)

Novel systems and methods for remotely detecting at least one constituent of a gas via infrared detection are provided. A system includes at least one extended source of broadband infrared radiation and a spectrally sensitive receiver positioned remotely from the source. The source and the receiver are oriented such that a surface of the source is in the field of view of the receiver. The source includes a heating component thermally coupled to the surface, and the heating component is configured to heat the surface to a temperature above ambient temperature. The receiver is operable to collect spectral infrared absorption data representative of a gas present between the source and the receiver. The invention advantageously overcomes significant difficulties associated with active infrared detection techniques known in the art, and provides an infrared detection technique with a much greater sensitivity than passive infrared detection techniques known in the art.

Johnson, Timothy J. (Pasco, WA)

2007-11-27

211

Methods and systems for remote detection of gases  

Energy Technology Data Exchange (ETDEWEB)

Novel systems and methods for remotely detecting at least one constituent of a gas via infrared detection are provided. A system includes at least one extended source of broadband infrared radiation and a spectrally sensitive receiver positioned remotely from the source. The source and the receiver are oriented such that a surface of the source is in the field of view of the receiver. The source includes a heating component thermally coupled to the surface, and the heating component is configured to heat the surface to a temperature above ambient temperature. The receiver is operable to collect spectral infrared absorption data representative of a gas present between the source and the receiver. The invention advantageously overcomes significant difficulties associated with active infrared detection techniques known in the art, and provides an infrared detection technique with a much greater sensitivity than passive infrared detection techniques known in the art.

Johnson, Timothy J

2012-09-18

212

GMDD: a database of GMO detection methods  

Science.gov (United States)

Background Since more than one hundred events of genetically modified organisms (GMOs) have been developed and approved for commercialization in global area, the GMO analysis methods are essential for the enforcement of GMO labelling regulations. Protein and nucleic acid-based detection techniques have been developed and utilized for GMOs identification and quantification. However, the information for harmonization and standardization of GMO analysis methods at global level is needed. Results GMO Detection method Database (GMDD) has collected almost all the previous developed and reported GMOs detection methods, which have been grouped by different strategies (screen-, gene-, construct-, and event-specific), and also provide a user-friendly search service of the detection methods by GMO event name, exogenous gene, or protein information, etc. In this database, users can obtain the sequences of exogenous integration, which will facilitate PCR primers and probes design. Also the information on endogenous genes, certified reference materials, reference molecules, and the validation status of developed methods is included in this database. Furthermore, registered users can also submit new detection methods and sequences to this database, and the newly submitted information will be released soon after being checked. Conclusion GMDD contains comprehensive information of GMO detection methods. The database will make the GMOs analysis much easier.

Dong, Wei; Yang, Litao; Shen, Kailin; Kim, Banghyun; Kleter, Gijs A; Marvin, Hans JP; Guo, Rong; Liang, Wanqi; Zhang, Dabing

2008-01-01

213

GMDD: a database of GMO detection methods  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Since more than one hundred events of genetically modified organisms (GMOs) have been developed and approved for commercialization in global area, the GMO analysis methods are essential for the enforcement of GMO labelling regulations. Protein and nucleic acid-based detection techniques have been developed and utilized for GMOs identification and quantification. However, the information for harmonization and standardization of GMO analysis methods at global level is needed. Results GMO Detection method Database (GMDD) has collected almost all the previous developed and reported GMOs detection methods, which have been grouped by different strategies (screen-, gene-, construct-, and event-specific), and also provide a user-friendly search service of the detection methods by GMO event name, exogenous gene, or protein information, etc. In this database, users can obtain the sequences of exogenous integration, which will facilitate PCR primers and probes design. Also the information on endogenous genes, certified reference materials, reference molecules, and the validation status of developed methods is included in this database. Furthermore, registered users can also submit new detection methods and sequences to this database, and the newly submitted information will be released soon after being checked. Conclusion GMDD contains comprehensive information of GMO detection methods. The database will make the GMOs analysis much easier.

Dong Wei; Yang Litao; Shen Kailin; Kim Banghyun; Kleter Gijs A; Marvin Hans JP; Guo Rong; Liang Wanqi; Zhang Dabing

2008-01-01

214

Micronuclei: sensitivity for the detection of radiation induced damage  

International Nuclear Information System (INIS)

The in vitro cytokinesis-block (CB) micronucleus (MN) assay for human peripheral blood has been used extensively for the assessment of chromosomal damage induced by ionizing radiation and chemicals and considered a suitable biological dosimeter for estimating in vivo whole body exposures, particularly in the case of large scale radiation accidents. One of the major drawbacks of the MN assay is its reduced sensitivity for the detection of damage induced by low doses of low LET radiation, due to the high variability among the spontaneous MN frequencies. It is suggested that age, smoking habit and sex are the main confounding factors that contribute to the observed variability. Previous work in our laboratory, shows a significant positive correlation of the spontaneous and radiation induced MN frequencies with age and smoking habit, the latter being the strongest confounder. These findings led to in vitro studies of the dose-response relationships for smoking and non smoking donors evaluated separately, using 60Co ? rays. The objectives of the present work are: 1-To increase the amount of data of the dose-response relationships, using ? rays from a 60Co source, for smoking and non smoking donors, in order to find, if applicable, a correction factor for the calibration curve that takes into account the smoking habit of the individual in the case of accidental overexposure dose assessment, particularlow dose range. 2-To establish general conclusions on the current state of the technique. The sample for smoking and non smoking calibration curves was enlarged in the range of 0Gy to 2Gy. The fitting of both curves, performed up to the 2Gy dose, resulted in a linear quadratic model. MN distribution among bi nucleated cells was found to be over dispersed with respect to Poisson distribution, the average ratio of variance to mean being 1.13 for non smokers and 1.17 for smokers. Each fitted calibration curve, for smoking and non smoking donors, fell within the 95% confidence curves of the other, with the exception of the spontaneous frequency values of both calibration curves. Thus, for the accidental overexposure dose assessment it seems to be appropriate to use a pooled data (smokers + non smokers) calibration curve and in the case of dose assessment up to 0.5Gy, it is convenient to use the corresponding spontaneous term in the yield equation; associated to the individual smoking habit condition. General conclusions: 1-The high and variable spontaneous MN frequency prevents an adequate dose estimation below 0.2-0.3Gy of low LET radiation. 2-At high doses, of low LET radiation, the sensitivity of the MN test is lower than the conventional aberration methods (dicentrics) due to the smaller squared term in the yield equation. 3-Radiation induced MN tend to be over dispersed with respect to Poisson distribution. Over dispersion increases the standard error on the observed yield and thus the uncertainties on the dose estimation. (author)

1998-01-01

215

Zinc oxide nanoplates for ultraviolet radiation detection  

Science.gov (United States)

An ultraviolet photosensor based on ZnO nanoplates has been successfully fabricated. ZnO nanoplates was synthesized by sonochemical method and coated on Cu interdigitated electrodes. The method is simple, rapid and applicable to research prototypes for further studies of ZnO nanoplates for nano-device applications. The current-voltage (I-V) characteristics show linear behavior and the photosensor exhibits a response of ~803mA/W for UV light under 15 V bias. Compared to other nano detectors, the fabricated detector shows fast photo response with a rise time of 150 ms and fall time of 50 ms compared to the other nanomaterial based photosensors.

Dolatyari, Mahboubeh; Amini, Elham; Shekari, Hemayat; Bakhtiari, Akbar; Rostami, Ali

2011-11-01

216

CURRENT METHODS FOR DETECTION OF CRYPTOSPORIDIUM SPECIES  

Science.gov (United States)

Current methods for detecting protozoa in water produce results that are highly variable. It is difficult to determine if the methods themselves, or the procedures for testing these methods, are the source of the variability. If testing procedures are responsible for high varia...

217

Comparing Aberration Detection Methods with Simulated Data  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We compared aberration detection methods requiring historical data to those that require little background by using simulated data. Methods that require less historical data are as sensitive and specific as those that require 3–5 years of data. These simulations can determine which method produces a...

Hutwagner, Lori; Browne, Timothy; Seeman, G. Matthew; Fleischauer, Aaron T.

218

Advanced Scintillator Crystal for Various Radiation Detection  

Directory of Open Access Journals (Sweden)

Full Text Available Recently halide scintillator materials, such as cerium doped LaBr3 or LaCl3 crystalshave proven to be novel inorganic scintillator for gamma-ray detection andspectroscopy. Both materials exhibit exceptional scintillation properties such as highlight output, fast response, and excellent energy resolution. However, these materialsare highly hygroscopic, hard to grow due to thermal stressing then end up cracking andsuffer from the self-activity. A search for high resolution, high light yields, and nonhygroscopicmaterials are highly desirable to advance the scintillator technology. Thispaper presents the crystal growth of a new scintillator material, lanthanum dopedcerium bromide (CeBr3:3%LaBr3), and its optical characteristics. In comparison withthe high performance Ce-doped LaBr3 or LaCl3 , CeBr3:3%LaBr3 crystals are lesshygroscopic, have higher energy resolution (R~ 8% at 662 keV) and higher light yield(67,000 Ph/MeV±3000). Preliminary results on the growth of CeBr3:3%La crystals arepresented along with comparison of its luminescence properties with other well-knowninorganic scintillators.

Rastgo Hawrami; Aziz Hama-Rahim Fatah; Kharman Akram Faraj

2011-01-01

219

METHOD FOR DETECTING MICROORGANISMS IN A BIOLOGICAL SAMPLE  

UK PubMed Central (United Kingdom)

This invention relates to a method for detecting at least one specific microorganism in a biological sample, said method comprising the following steps: a) culturing said biological sample in a culture medium, b) subjecting said culture medium to at least two radiations each presenting a specific wavelength, c) obtaining at least two different images of said culture medium using at least two reading systems, d) combining said at least two different images to produce at least one combined artificial image, and e) analyzing said combined artificial image to detect the presence of said at least one specific microorganism in the biological sample. The invention also relates to a device for application of the detection method according to this invention.

RAMBACH ALAIN

220

Methods and Compositions for Detecting Colon Cancers.  

Science.gov (United States)

This application describes methods and compositions for detecting and treating vimentin-associated neoplasia. Differential methylation of the vimentin nucleotide sequences has been observed in vimentin-associated neoplasia such as colon neoplasia.

S. D. Markowitz

2004-01-01

 
 
 
 
221

METHODS AND COMPOSITIONS FOR ANALYTE DETECTION  

UK PubMed Central (United Kingdom)

The present invention is directed to methods and apparatus for detection of one or more analytes. Analytes include agents or components of infectious agents such as pathogenic virus, as well as enzymes, proteins and biomarkers.

EGAN RICHARD LASWELL; LIDGARD GRAHAM PETER; BOOKER DAVID DICKSON; JOHNSON CHRISTOPHER JOHANN; BELENKY ALEXANDER; VUKAJLOVICH STAN; ZEIS JOHN; CASTANON SCOTT

222

Automated Methods for Multiplexed Pathogen Detection  

Energy Technology Data Exchange (ETDEWEB)

Detection of pathogenic microorganisms in environmental samples is a difficult process. Concentration of the organisms of interest also co-concentrates inhibitors of many end-point detection methods, notably, nucleic acid methods. In addition, sensitive, highly multiplexed pathogen detection continues to be problematic. The primary function of the BEADS (Biodetection Enabling Analyte Delivery System) platform is the automated concentration and purification of target analytes from interfering substances, often present in these samples, via a renewable surface column. In one version of BEADS, automated immunomagnetic separation (IMS) is used to separate cells from their samples. Captured cells are transferred to a flow-through thermal cycler where PCR, using labeled primers, is performed. PCR products are then detected by hybridization to a DNA suspension array. In another version of BEADS, cell lysis is performed, and community RNA is purified and directly labeled. Multiplexed detection is accomplished by direct hybridization of the RNA to a planar microarray. The integrated IMS/PCR version of BEADS can successfully purify and amplify 10 E. coli O157:H7 cells from river water samples. Multiplexed PCR assays for the simultaneous detection of E. coli O157:H7, Salmonella, and Shigella on bead suspension arrays was demonstrated for the detection of as few as 100 cells for each organism. Results for the RNA version of BEADS are also showing promising results. Automation yields highly purified RNA, suitable for multiplexed detection on microarrays, with microarray detection specificity equivalent to PCR. Both versions of the BEADS platform show great promise for automated pathogen detection from environmental samples. Highly multiplexed pathogen detection using PCR continues to be problematic, but may be required for trace detection in large volume samples. The RNA approach solves the issues of highly multiplexed PCR and provides ''live vs. dead'' capabilities. However, sensitivity of the method will need to be improved for RNA analysis to replace PCR.

Straub, Tim M.; Dockendorff, Brian P.; Quinonez-Diaz, Maria D.; Valdez, Catherine O.; Shutthanandan, Janani I.; Tarasevich, Barbara J.; Grate, Jay W.; Bruckner-Lea, Cindy J.

2005-09-01

223

Detection of radiation pressure acting on 2009 BD  

CERN Multimedia

We report the direct detection of radiation pressure on the asteroid 2009 BD, one of the smallest multi-opposition near-Earth objects currently known, with H ~ 28.4. Under the purely gravitational model of NEODyS the object is currently considered a possible future impactor, with impact solutions starting in 2071. The detection of a radiation-related acceleration allows us to estimate an Area to Mass Ratio (AMR) for the object, that can be converted (under some assumptions) into a range of possible values for its average density. Our result AMR = (2.97 \\pm 0.33) x 10^(-4) m^2 kg^(-1) is compatible with the object being of natural origin, and it is narrow enough to exclude a man-made nature. The possible origin of this object, its future observability, and the importance of radiation pressure in the impact monitoring process, are also discussed.

Micheli, Marco; Elliott, Garrett T

2011-01-01

224

PIK3CA gene mutation detection probe, detection liquid phase chip and detection method thereof  

UK PubMed Central (United Kingdom)

The invention discloses a PIK3CA gene mutation site detection probe, a detection liquid phase chip and a detection method thereof. The PIK3CA gene mutation detection liquid phase chip mainly comprises a microball covered with a probe and a primer for amplifying a target sequence carrying a 9th exon and/or a 20th exon. The PIK3CA gene mutation detection liquid phase chip and the detection method can help simultaneously detect the sites with relatively higher frequency of the PIK3CA gene mutation, and can separately detect the 9th exon and the 20th exon or detect the 9th exon and the 20th exon at the same time, and the detection has uniform reaction condition, good specificity of detection results, high sensitivity, good accuracy up to 90% and short detection time.

JIASEN XU; YUANJIE GUO

225

Methods for the detection of marine toxins  

Energy Technology Data Exchange (ETDEWEB)

Toxic materials have been dumped into the seas from waste streams and other pollutant sources such as runoff, etc. For protection of public health, it is essential that rapid, reliable and simple methods exist to detect marine toxins in seafoods. In addition, it is necessary to develop methods requiring a minimum of test material. Pure standards for many of the marine toxins are scarce. Reduced sample requirements extend the utility of detection methods in research and forensic applications as well. In the past, there was much reliance on the animal bioassay; however, this dependence hopefully will be reduced as newer instrumental techniques (chromatographic, mass spectrometric, electrophoretic), biochemical (immunochemical, receptor site assay), and cell bioassay methods are developed with a higher degree of precision and specificity. It is beneficial that a multiplicity of methods be available to detect marine toxins in seafoods. Each method has unique advantages and disadvantages.

Wekell, M.M.; Manger, R.M.; Hadley, S.W.; Hungerford, J.M. [Food & Drug Administration, Bothell, WA (United States)

1995-12-01

226

Apparatus and methods for detecting chemical permeation  

Energy Technology Data Exchange (ETDEWEB)

Apparatus and methods for detecting the permeation of hazardous or toxic chemicals through protective clothing are disclosed. The hazardous or toxic chemicals of interest do not possess the spectral characteristic of luminescence. The apparatus and methods utilize a spectrochemical modification technique to detect the luminescence quenching of an indicator compound which upon permeation of the chemical through the protective clothing, the indicator is exposed to the chemical, thus indicating chemical permeation.

Vo-Dinh, Tuan (Knoxville, TN)

1994-01-01

227

Detection of atrial myxomas by radionuclide methods  

International Nuclear Information System (INIS)

[en] Two cases of right atrial myxomas and one case of left atrial myxoma detected by radionuclide methods are reported. The value of these methods is discussed, as well as the appropriate techniques to be used: the simple sequential gamma-angiocardiography appears sufficient for the detection of right atrial myxomas, whereas the electrocardiographically gated techniques, especially the gated first-pass, are preferable for the diagnosis of left atrial myxomas

1980-01-01

228

Evaluation of potassium nitrate for gamma-radiation detection  

International Nuclear Information System (INIS)

Pellets of potassium nitrate (KNO3) were evaluated to verify if they can be employed as dosimetric material for high dose measurements in routine use of radiation monitoring in radiation processing plants. The spectrophotometry in the visible region was used as detection technique. Pellets of KNO3 were dissolved in pure water to allow the optical absorption measurements before and after irradiation with 60 Co gamma radiation source, calibrated with Fricke solution reference dosimeter. The absorption spectrum of the KNO3 solution was investigated in the wavelength region between 500 and 600 nm to determine the maximum absorption wavelength. Dosimetric properties such as dose rate dependence in the interval between 0.059 and 3.82 kGy/h, angular radiation incidence dependence between 0 and 90 degrees and dose response in the range between 1-150 kGy were investigated. The obtained results show the proposed dosimetric material can be useful in high dose measurements. (author)

2001-05-04

229

Radionuclide detection devices and associated methods  

Energy Technology Data Exchange (ETDEWEB)

Radionuclide detection devices comprise a fluid cell comprising a flow channel for a fluid stream. A radionuclide collector is positioned within the flow channel and configured to concentrate one or more radionuclides from the fluid stream onto at least a portion of the radionuclide collector. A scintillator for generating scintillation pulses responsive to an occurrence of a decay event is positioned proximate at least a portion of the radionuclide collector and adjacent to a detection system for detecting the scintillation pulses. Methods of selectively detecting a radionuclide are also provided.

Mann, Nicholas R. (Rigby, ID); Lister, Tedd E. (Idaho Falls, ID); Tranter, Troy J. (Idaho Falls, ID)

2011-03-08

230

Method for detecting chrysanthemum chlorotic mottle virus  

UK PubMed Central (United Kingdom)

The invention aims to provide a method for detecting Chrysanthemumchloriticmottleviroid (CChMVd). The method utilizes a loop-mediated isothermal amplification (LAMP) reaction to detect the Chrysanthemumchloriticmottleviroid (CChMVd) the method orderly comprises the steps of the preparation of a reaction system, incubation treatment, inactivation treatment and product detection the reaction system comprises 0.6 to 1.4mol/L of Betaine, 0.25 to 2.0mmol/L of dNTP, 2 to 10mmol/L of Mg<2+>, an outer primer, and an inner primer and the concentration ratio of the inner primer to the outer primer is between1:1 and 1:8. The method has the advantages that the method does not need special instruments (such as a PCR instrument), and is quicker and more economical than the prior method in a laboratory and the method has simple and convenient identification and extremely high specificity, and can judge whether a target fragment is amplified through the precipitation turbidity observed by naked eyes or detected by an ultraviolet imaging system of a turbidimeter, thereby judging whether a sample plant used for the detection is infected with the Chrysanthemumchloriticmottleviroid without using a gel electrophoresis method to observe.

YONGQIN WANG; CONGLIN HUANG; ZHONGYI WU; XIUHAI ZHANG; CHUNHUA LI; HONGXIA LIANG; JIA LIU

231

Coverage methods for early groundwater contamination detection.  

Science.gov (United States)

A method based on space-filling coverage designs to optimize groundwater monitoring networks for plume detection and quantification is proposed. Space-filling objective functions are then compared with more classical functions. The method was applied to a hypothetical case-study with 160 candidate locations, resulting in final optimal design monitoring networks with 40 locations. Results show that the method is superior to those based strictly on the probability of contamination detection for quantifying maximum and mean values. In the light of these results fractal properties of space-filling coverage methods and of simulated annealing are also discussed. PMID:23435904

Nunes, Luís Miguel; da Conceição Cunha, Maria; Ribeiro, Luís

2013-02-24

232

Coverage methods for early groundwater contamination detection.  

UK PubMed Central (United Kingdom)

A method based on space-filling coverage designs to optimize groundwater monitoring networks for plume detection and quantification is proposed. Space-filling objective functions are then compared with more classical functions. The method was applied to a hypothetical case-study with 160 candidate locations, resulting in final optimal design monitoring networks with 40 locations. Results show that the method is superior to those based strictly on the probability of contamination detection for quantifying maximum and mean values. In the light of these results fractal properties of space-filling coverage methods and of simulated annealing are also discussed.

Nunes LM; da Conceição Cunha M; Ribeiro L

2013-05-01

233

High sensitivity leak detection method and apparatus  

Energy Technology Data Exchange (ETDEWEB)

An improved leak detection method is provided that utilizes the cyclic adsorption and desorption of accumulated helium on a non-porous metallic surface. The method provides reliable leak detection at superfluid helium temperatures. The zero drift that is associated with residual gas analyzers in common leak detectors is virtually eliminated by utilizing a time integration technique. The sensitivity of the apparatus of this disclosure is capable of detecting leaks as small as 1.times.10.sup.-18 atm cc sec.sup.-1.

Myneni, Ganapatic R. (Grafton, VA)

1994-01-01

234

Methods for detecting fouling in heat exchangers  

Energy Technology Data Exchange (ETDEWEB)

Heat exchangers are frequently used in district heating systems, at power plants and public homes. Detecting fouling in district heating heat exchangers is of great importance. There are currently many different ways to detect fouling in heat exchangers that either rely on physical examination of the heat exchanger or modeling the heat exchanger and use measurements of the heat exchanger to predict fouling. The method describe in the paper can be used to detect fouling by using the inlet and outlet temperatures and either the hot or cold mass flow. Results of the method described on a simulated data are given

Gudmundsson, Oddgeir; Palsson, Olafur Petur; Palsson, Halldor (Faculty of Industrial Engineering, Mechanical Engineering and Computer Science, Univ. of Iceland, Reykjavik (Iceland)); Lalot, Sylvain (LME, Univ. of Valenciennes and Hainaut Cambresis, IUT (France))

2008-09-15

235

Rapid quantitative detection method and detection kit for clostridium perfringens  

UK PubMed Central (United Kingdom)

The invention provides a method for quantitative detection of clostridium perfringens, including the following steps: (a) obtaining secretion of a patient and extracting genomic DNA of bacteria therein (b) carrying out fluorescence quantitative PCR amplification on the DNA obtained in the step (a) by taking the sequences SEQ ID NO:1 and SEQ ID NO:2 as primers and the sequence SEQ ID NO:3 as a probe (c) plotting a standard curve between CT value and the concentration of the clostridium perfringens and carrying out quantitative account on the clostridium perfringens in the secretion of the patient according to the amplification result of the step (b). The method of the invention has high specificity, sensibility and quantitative accuracy, the existence of bacteria or virus can be detected, and the whole detection process can be completed within 2-3 hours about 10 bacteria can be detected at least, quantitative error is less than 5%, and indexes such specificity, agent stability and the like accord with relevant national standard. Meanwhile, the invention utilizes the fluorescence quantitative PCR method, and 96 or 384 samples can be detected once.

YULING SHI; LINHAI LI; LUXIA WANG; YANG LIAO; LIDAN CHEN; JIANYUN CHEN; YASONG ZHANG; LANLAN ZENG

236

STETHOSCOPE ADAPTED TO COMPRISE A RADIATION MONITOR METHOD AND DEVICE  

UK PubMed Central (United Kingdom)

A method and device for monitoring a healthcare worker's exposure to radiation wherein a stethoscope is adapted to comprise a radiation monitor. The radiation monitor may be of instruments for measuring radiation including Geiger-Muller counters, scintillation detectors, photographic emulsions and various ionization chambers. The stethoscope may be acoustic or electronic or combined.

KARELL MANUEL L

237

ANOLE Portable Radiation Detection System Field Test and Evaluation Campaign  

Energy Technology Data Exchange (ETDEWEB)

Handheld, backpack, and mobile sensors are elements of the Global Nuclear Detection System for the interdiction and control of illicit radiological and nuclear materials. They are used by the U.S. Department of Homeland Security (DHS) and other government agencies and organizations in various roles for border protection, law enforcement, and nonproliferation monitoring. In order to systematically document the operational performance of the common commercial off-the-shelf portable radiation detection systems, the DHS Domestic Nuclear Detection Office conducted a test and evaluation campaign conducted at the Nevada Test Site from January 18 to February 27, 2006. Named “Anole,” it was the first test of its kind in terms of technical design and test complexities. The Anole test results offer users information for selecting appropriate mission-specific portable radiation detection systems. The campaign also offered manufacturers the opportunity to submit their equipment for independent operationally relevant testing to subsequently improve their detector performance. This paper will present the design, execution, and methodologies of the DHS Anole portable radiation detection system test campaign.

Chris A. Hodge

2007-07-12

238

Application of organic semiconductors for the detection of ionizing radiations  

International Nuclear Information System (INIS)

One year aged organic bilayer Al/PCTDA/CuPc/ITO structure prepared with ICB deposition method has been used to evaluate the influence of ionising radiation to electrical properties of the structure. Small sources of ?, ? and ? radiation were used for preliminary measurements. Capacitance and current measurements were performed on samples with and without presence of ionising radiation and results compared. Effect of ? and ? radiation has not been confirmed due to the limited activity of available sources. Presence of ? radiation has noticeably changed the capacitance of reversely biased structure and produced increase of current through the structure. We have tried to explain the capacitance properties using the model previously developed for the organic bilayer structures, but we did not manage to resolve all effects involved. (author)

2006-01-01

239

Detection of DNA damage induced by space radiation in Mir and space shuttle  

Energy Technology Data Exchange (ETDEWEB)

Although physical monitoring of space radiation hasbeen accomplished, we aim to measure exact DNA damage as caused by space radiation. If DNA damage is caused by space radiation, we can detect DNA damage dependent on the length of the space flight periods byusing post-labeling methods. To detect DNA damage caused by space radiation, we placed fixed human cervical carcinoma (HeLa) cells in the Russian Mir space station for 40 days and in an American space shuttle for 9 days. After landing, we labeled space-radiation-induced DNA strand breaks by enzymatic incorporation of [{sup 3}H]-deoxyadenosine triphosphate (dATP) with terminal deoxyribo-nucleotidyl transferase (TdT). We detected DNA damage as many grains on fixed silver emulsion resulting from {beta}-rays emitted from {sup 3}H-atoms in the nuclei of the cells placed in the Mir-station (J/Mir mission, STS-89), but detected hardly any in the ground control sample. In thespace shuttle samples (S/MM-8), the number of cellshaving many grains was lower than that in the J/Mir mission samples. These results suggest that DNA damage is caused by space radiation and that it is dependent on the length of the space flight. (author)

Ohnishi, Takeo; Ohnishi, Ken; Takahashi, Akihisa [Nara Medical Univ, Kashihara (Japan); Taniguchi, Yoshitaka [Toray Research Center Inc., Kamakura, Kanagawa (Japan); Sato, Masaru; Nakano, Tamotsu [National Space Development Agency of Japan, Tsukuba, Ibaraki (Japan); Nagaoka, Shunji [Fujita Health Univ., Toyoake, Aichi (Japan). School of Health Sciences

2002-12-01

240

Detection of DNA damage induced by space radiation in Mir and space shuttle  

International Nuclear Information System (INIS)

Although physical monitoring of space radiation hasbeen accomplished, we aim to measure exact DNA damage as caused by space radiation. If DNA damage is caused by space radiation, we can detect DNA damage dependent on the length of the space flight periods byusing post-labeling methods. To detect DNA damage caused by space radiation, we placed fixed human cervical carcinoma (HeLa) cells in the Russian Mir space station for 40 days and in an American space shuttle for 9 days. After landing, we labeled space-radiation-induced DNA strand breaks by enzymatic incorporation of [3H]-deoxyadenosine triphosphate (dATP) with terminal deoxyribo-nucleotidyl transferase (TdT). We detected DNA damage as many grains on fixed silver emulsion resulting from ?-rays emitted from 3H-atoms in the nuclei of the cells placed in the Mir-station (J/Mir mission, STS-89), but detected hardly any in the ground control sample. In thespace shuttle samples (S/MM-8), the number of cellshaving many grains was lower than that in the J/Mir mission samples. These results suggest that DNA damage is caused by space radiation and that it is dependent on the length of the space flight. (author)

2002-01-01

 
 
 
 
241

Detection of irradiated meats by hydrocarbon method  

International Nuclear Information System (INIS)

Meats, for example, lamb, razorback, wild duck and turkey were irradiated by gamma ray, and the amounts of hydrocarbons formed from fatty acids were measured. Since C20:0 was found from wild duck and turkey. C1-18:1 was recommended for internal standard. Good correlation was found between the amount of hydrocarbons and the doses of gamma irradiation. This study shows that such hydrocarbons induced after radiation procedure as C1,7-16:2, C8-17:1, C1-14:1, and C15:0 may make it possible to detect irradiated lamb, razorback, wild duck and turkey. (author)

2005-01-01

242

Passive radiation detection using optically active CMOS sensors  

Science.gov (United States)

Recently, there have been a number of small-scale and hobbyist successes in employing commodity CMOS-based camera sensors for radiation detection. For example, several smartphone applications initially developed for use in areas near the Fukushima nuclear disaster are capable of detecting radiation using a cell phone camera, provided opaque tape is placed over the lens. In all current useful implementations, it is required that the sensor not be exposed to visible light. We seek to build a system that does not have this restriction. While building such a system would require sophisticated signal processing, it would nevertheless provide great benefits. In addition to fulfilling their primary function of image capture, cameras would also be able to detect unknown radiation sources even when the danger is considered to be low or non-existent. By experimentally profiling the image artifacts generated by gamma ray and ? particle impacts, algorithms are developed to identify the unique features of radiation exposure, while discarding optical interaction and thermal noise effects. Preliminary results focus on achieving this goal in a laboratory setting, without regard to integration time or computational complexity. However, future work will seek to address these additional issues.

Dosiek, Luke; Schalk, Patrick D.

2013-05-01

243

Ultrafast Radiation Detection by Modulation of an Optical Probe Beam  

Energy Technology Data Exchange (ETDEWEB)

We describe a new class of radiation sensor that utilizes optical interferometry to measure radiation-induced changes in the optical refractive index of a semiconductor sensor medium. Radiation absorption in the sensor material produces a transient, non-equilibrium, electron-hole pair distribution that locally modifies the complex, optical refractive index of the sensor medium. Changes in the real (imaginary) part of the local refractive index produce a differential phase shift (absorption) of an optical probe used to interrogate the sensor material. In contrast to conventional radiation detectors where signal levels are proportional to the incident energy, signal levels in these optical sensors are proportional to the incident radiation energy flux. This allows for reduction of the sensor form factor with no degradation in detection sensitivity. Furthermore, since the radiation induced, non-equilibrium electron-hole pair distribution is effectively measured ''in place'' there is no requirement to spatially separate and collect the generated charges; consequently, the sensor risetime is of the order of the hot-electron thermalization time {le} 10 fs and the duration of the index perturbation is determined by the carrier recombination time which is of order {approx} 600 fs in, direct-bandgap semiconductors, with a high density of recombination defects; consequently, the optical sensors can be engineered with sub-ps temporal response. A series of detectors were designed, and incorporated into Mach Zehnder and Fabry-Perot interferometer-based detection systems: proof of concept, lower detection sensitivity, Mach-Zehnder detectors were characterized at beamline 6.3 at SSRL; three generations of high sensitivity single element and imaging Fabry-Perot detectors were measured at the LLNL Europa facility. Our results indicate that this technology can be used to provide x-ray detectors and x-ray imaging systems with single x-ray sensitivity and S/N {approx} 30 at x-ray energies {approx} 10 keV.

Vernon, S P; Lowry, M E

2006-02-22

244

Properties study of ZnO:Ga crystal on pulsed radiation detections  

International Nuclear Information System (INIS)

In this paper, properties on pulsed radiation detections of ZnO:Ga crystal grew by a magnetron sputtering method were studied. The time response to pulsed laser, pulsed hard X rays and single ? particles, the energy response to pulsed hard X ray, the scintillation efficiency to ? rays, the response to pulsed proton, and the relations of the light intensity varied with the proton energy were measured and analyzed in detail. Results show that the ZnO:Ga crystal has potential applications in the regime of pulse radiation detection .(authors)

2010-01-01

245

A method of detecting coherent synchrotron modes  

International Nuclear Information System (INIS)

A method for measuring coherent longitudinal synchrotron modes is developed and tested at the Indiana University Cyclotron Facility Cooler Ring. This method can be used to detect the onset of coherent instability and can provide important diagnosis for the control of beam brightness. Some possible improvement of this technique is discussed. (orig.).

1996-01-01

246

Radiation Detection Scenario Analysis Toolbox (RADSAT) Test Case Implementation Final Report  

Energy Technology Data Exchange (ETDEWEB)

Final report for the project. This project was designed to demonstrate the use of the Radiation Detection Scenario Analysis Toolbox (RADSAT) radiation detection transport modeling package (developed in a previous NA-22 project) for specific radiation detection scenarios important to proliferation detection.

Shaver, Mark W.

2010-09-27

247

Detection of radiation from electrochemical cell intensifying beta decay.  

UK PubMed Central (United Kingdom)

The predictions of relic neutrino existence and neutrino anomalous magnetic moment existence, as well as the solution of the Dirac equation for a neutral particle with an anomalous magnetic moment in the Coulomb field imply the existence of neutrino matter component. In this work the radiation intensifying (60)Co and (137)Cs beta decays by (0.42 ± 0.05)% and (0.160 ± 0.012)% has been detected from the end electrochemical cell. The radiation interaction cross-section with radioactive nuclei is more than 10(-30)cm(2).

Muromtsev VI; Veprev DP

2012-08-01

248

Flexible Receiver Radiation Detection System (FRRDS) Users Manual  

International Nuclear Information System (INIS)

[en] The Flexible Receiver Radiation Detection System (FRRDS) comprises a control computer, a remote data acquisition subsystem, and three hyperpure germanium gamma radiation detectors. The scope of this document is the description of various steps for the orderly start-up, use, and shutdown of the FRRDS. Only those items necessary for these oprations are included. This document is a companion to WHC-SD-W151-UM-002, 'Operating Instructions for the 42 Inch Flexible Receiver,' WHC-SD-W151-UM-003, 'Operating Instructions for the 4-6 Inch Flexible Receiver,' and the vendor supplied system users guide (Ref. 6)

1996-01-01

249

TARGET DNA DETECTION METHOD AND TARGET DNA DETECTION KIT  

UK PubMed Central (United Kingdom)

The present invention provides a method for detecting a target DNA easily and highly accurately through simultaneous analysis of a sense strand and an antisense strand of the target DNA, and a kit therefor. The target DNA detection method of the present invention is a method for detecting a target DNA composed of a sense strand having a target nucleotide sequence and an antisense strand complementary to the sense strand, wherein: a first oligonucleotide which hybridizes with the sense strand, and a second oligonucleotide which hybridizes with the antisense strand are used at least a part of a region, of the antisense strand, which hybridizes with the second oligonucleotide is complementary to at least a part of a region, of the sense strand, which hybridizes with the first oligonucleotide and the first oligonucleotide and the second oligonucleotide are simultaneously added into one reaction solution to effect respective hybridizations with the target DNA, followed by ligation reactions and/or PCR, thereby detecting resultant products.

TANABE TETSUYA

250

Detection of radiation from a Ti:sapphire laser with a high space - time resolution  

International Nuclear Information System (INIS)

A high space - time resolution is achieved in detection of radiation from a Ti:sapphire laser by the methods of femtosecond photoelectronics. A time resolution of 2 x 10-13 s is obtained at wavelength of 800 nm in a linear scan regime for a streak speed of 5 x 1010 cm s-1, an input power density of (1 - 5) x 103 W cm-2, and a linear dynamic detection range no more than 10. (letters)

2002-04-30

251

Detection methods for autologous blood doping.  

UK PubMed Central (United Kingdom)

The use of blood doping is forbidden by the World Anti-Doping Agency. Several practices, such as blood transfusions are used to increase oxygen delivery to muscles and all of them are highly pursued. In this regard, the development of accurate methodologies for detecting these prohibited practices is one of the current aims of the anti-doping control laboratories. Flow cytometry methods are able to detect allogeneic blood transfusions but there is no official methodology available to detect autologous blood transfusions. This paper reviews protocols, including the Athlete Biological Passport, that use indirect markers to detect misuse of blood transfusions, especially autologous blood transfusions. The methods of total haemoglobin mass measurements and the detection of metabolites of blood bags plasticizers in urine are reviewed. The latter seems to be an important step forward because it is a fast screening method and it is based on urine, a fluid widely available for doping control. Other innovative approaches to blood transfusion detection are also mentioned. A combination of the reported methodologies and the implementation of the Athlete Biological Passport is becoming a promising approach.

Segura J; Monfort N; Ventura R

2012-11-01

252

Numerical methods in multidimensional radiative transfer  

CERN Multimedia

Offers an overview of the numerical modelling of radiation fields in multidimensional geometries. This book covers advances and problems in the mathematical treatment of the radiative transfer equation, a partial integro-differential equation of high dimension that describes the propagation of the radiation in various fields.

Meinköhn, Erik

2008-01-01

253

Small Teleoperated Robot for Nuclear Radiation and Chemical Leak Detection  

Directory of Open Access Journals (Sweden)

Full Text Available In order to meet the actual requirements of nuclear radiation and chemical leak detection, and emergency response, a new small teleoperated robot for nuclear radiation and chemical detection is proposed. A small?size robot is manufactured according to technical requirements and the overall structure and control system is described. Meanwhile, based on the principles of human?robot interaction, a user?friendly human?robot interaction interface is designed to provide a good telepresence for the operator, helping the operator to perceive and judge the robot’s situation to better assist in making the right decisions and in giving timely operation instructions. The experiment results show the robot system operates reliably and meets the technical requirements.

Kui Qian; Aiguo Song; Jiatong Bao; Huatao Zhang

2012-01-01

254

2012 LA, an optimal astrometric target for radiation pressure detection  

Science.gov (United States)

We present our dynamical analysis of near-Earth object 2012 LA, derived from a collection of astrometric positions obtained by us with telescopes on Mauna Kea, in Hawaii, densely covering the entire 2012 apparition of the object. Clear evidence of non-gravitational acceleration, attributable to radiation pressure, is present in the complete dataset, but would not be detectable with the sparse sampling of the apparition obtained by other stations. Our determination of the Area to Mass Ratio of A/m = (0.335 ± 0.028) × 10?3 m2/kg is the most significant detection of radiation pressure obtained to date on any natural object. This value can be converted into a bulk density estimate of ?=460-210+260kg/m3, under certain assumptions on size, albedo and shape.

Micheli, Marco; Tholen, David J.; Elliott, Garrett T.

2013-09-01

255

Apparatus and methods for detecting chemical permeation  

Energy Technology Data Exchange (ETDEWEB)

Apparatus and methods for detecting the permeation of hazardous or toxic chemicals through protective clothing are disclosed. The hazardous or toxic chemicals of interest do not possess the spectral characteristic of luminescence. The apparatus and methods utilize a spectrochemical modification technique to detect the luminescence quenching of an indicator compound which upon permeation of the chemical through the protective clothing, the indicator is exposed to the chemical, thus indicating chemical permeation. The invention also relates to the fabrication of protective clothing materials. 13 figures.

Vo-Dinh, T.

1994-12-27

256

Noise Radiation Measure-Sound Power and its Test Methods  

Directory of Open Access Journals (Sweden)

Full Text Available This study mainly aims to study the characteristics and theory of sound radiation of steady-state vibration. Study shows that sound radiation power of steady-state vibration is constant. And taking excavator for experimental object by hemisphere surface method, the radiated sound power of the excavator is the same as testing the sound pressure on various surfaces based on relevant international standard. Finally, a test method of radiated sound power for cylindrical vibration object is proposed.

Zeng Xianren; Zuo Yanyan

2013-01-01

257

Development of a distributed radiation detection system using optical fibers  

Energy Technology Data Exchange (ETDEWEB)

We have confirmed the importance of temperature and dose rate for the response of Ge-doped fibers to radiation. A phenomenological model have been found to account for temperature and dose rate effects. From this model it is possible to make dose predictions from attenuation measurements when the temperature and dose rate are known. Ge-doped fibers have been found to have a relatively low sensitivity to both neutron and gamma radiation. In addition, temperature and dose rate dependencies complicate the analysis. However we point out that these problems may all be solved if we use fibers, such as P-doped fibers, which contain color centers of long lifetime. This would remove both the temperature and dose rate dependencies that complicate the use of Ge-doped fibers, in addition the radiation sensitivity is increased. Finally OTDR has been investigated as a possible read-out method for distributed radiation measurements. For our system the minimum pulse length was 3ns, giving a spatial resolution in the meter range and a response length to radiation of about 10 m if accurate dose values where to be obtained. We found OTDR to be a suitable method for radiation induced attenuation measurements in optical fibers, especially for long fiber lengths and long time scales where questions of light source stability becomes important for other systems. (S.Y.)

Jensen, F.; Inouchi, Goro; Takada, Eiji; Takahashi, Hiroyuki; Iguchi, Tetsuo; Nakazawa, Masaharu [Tokyo Univ. (Japan). Faculty of Engineering; Kakuta, Tsunemi

1996-07-01

258

Calculation methods of internal radiation dose  

International Nuclear Information System (INIS)

A description is made of the methods of calculating the internal radiation dose in man to be put together with the external dose, concerning the guideline dose values of the Atomic Energy Commission of Japan in connection with the principle of keeping the releases of radioactive materials in effluents of light-water-cooled nuclear power reactors to the environment as low as is reasonably achievable. A comparison is then made between the dose calculation methods announced by the Atomic Energy Commission of Japan and those by the U.S. Nuclear Regulatory Commission (Regulatory Guide 1.109). Features of the methods by the Atomic Energy Commission of Japan are: calculation of the doses in individuals of the critical groups outside of the reactors through critical exposure pathways due to major radionuclides in the effluents, usage of calculational models based on specific activities of radionuclides to estimate the doses via seafoods pathways, i.e. radioiodine in seaweed, and presentation of parameters for estimating the doses in Japanese people. (auth.)

1976-11-19

259

Method and apparatus for determining accuracy of radiation measurements made in the presence of background radiation  

International Nuclear Information System (INIS)

A radioactivity measuring instrument, and a method related to its use, for determining the radioactivity of a sample measured in the presence of significant background radiation, and for determining an error value relating to a specific probability of accuracy of the result are presented. Error values relating to the measurement of background radiation alone, and to the measurement of sample radiation and background radiation together, are combined to produce a true error value relating to the sample radiation alone

1977-01-01

260

Radiation Detection System for Prevention of Radiological and Nuclear Terrorism  

International Nuclear Information System (INIS)

After the September 11 terrorist attack, the threat of a potential for a radiological or nuclear terrorist attack became more apparent. The threats relating to radiological or nuclear materials include a Radiological Dispersion Device (RDD), an Improved Nuclear Device (IND) or a State Nuclear Device (such as a Soviet manufactured suitcase nuclear weapon). For more effective countermeasures against the disaster, multilayer protection concept - prevention of smuggling of radioactive or nuclear material into our country through seaports or airports, detection and prevention of the threat materials in transit on a road, and prevention of their entry into a target building - is recommended. Due to different surrounding circumstances of where detection system is deployed, different types of radiation detection systems are required. There have been no studies on characteristics of detection equipment required under Korean specific conditions. This paper provides information on technical requirements of radiation detection system to achieve multi-layer countermeasures for the purpose of protecting the public and environment against radiological and nuclear terrorism.

2007-01-01

 
 
 
 
261

Designing metal-organic frameworks for radiation detection  

International Nuclear Information System (INIS)

[en] Five metal-organic frameworks (MOFs) were synthesized and investigated via steady-state photoluminescence and radioluminescence measurements. Unique spectral features were observed in the 2.5 MeV proton spectra, corresponding to differences in the electronic and crystalline structures of each material. Targeted structural transformations and infiltration with extrinsic dopants were also employed to modify the luminescence of these frameworks, establishing MOFs as a platform to design new radiation detection materials.

2011-10-01

262

Application of single-chip microcomputer in radiation detection  

International Nuclear Information System (INIS)

[en] The single-chip microcomputer has some advantages in many aspects for example the strong function, the small volume, the low-power, firmed and reliable. It is used widely in the control of industry, instrument, communication and machine, etc.. The paper introduces that the single-chip microcomputer is used in radiation detection, mostly including the use of control, linear, compensation, calculation, prefabricated change, improving precision and training

1993-01-01

263

Novel methods for detecting buried explosive devices  

Energy Technology Data Exchange (ETDEWEB)

Oak Ridge National Laboratory (ORNL) and Quantum Magnetics, Inc. (QM) are exploring novel landmine detection technologies. Technologies considered here include bioreporter bacteria, swept acoustic resonance, nuclear quadrupole resonance (NQR), and semiotic data fusion. Bioreporter bacteria look promising for third-world humanitarian applications; they are inexpensive, and deployment does not require high-tech methods. Swept acoustic resonance may be a useful adjunct to magnetometers in humanitarian demining. For military demining, NQR is a promising method for detecting explosive substances; of 50,000 substances that have been tested, none has an NQR signature that can be mistaken for RDX or TNT. For both military and commercial demining, sensor fusion entails two daunting tasks, identifying fusible features in both present-day and emerging technologies, and devising a fusion algorithm that runs in real-time on cheap hardware. Preliminary research in these areas is encouraging. A bioreporter bacterium for TNT detection is under development. Investigation has just started in swept acoustic resonance as an approach to a cheap mine detector for humanitarian use. Real-time wavelet processing appears to be a key to extending NQR bomb detection into mine detection, including TNT-based mines. Recent discoveries in semiotics may be the breakthrough that will lead to a robust fused detection scheme.

Kercel, S.W.; Burlage, R.S.; Patek, D.R.; Smith, C.M. [Oak Ridge National Lab., TN (United States); Hibbs, A.D.; Rayner, T.J. [Quantum Magnetics, Inc., San Diego, CA (United States)

1997-04-01

264

Bremsstrahlung detection and chamber obstruction localisation using scanning radiation detectors  

International Nuclear Information System (INIS)

[en] The full text of publication follows. Radiation monitors consisting of scintillating plastic coupled to photomultipliers are used for diagnostic purposes. By scanning such a detector or a radiation scatterer, 2 applications are demonstrated: i) Monitoring of vacuum chamber conditioning by monitoring gas Bremsstrahlung from residual gas, and ii) Localisation of beam interception (beam losses) by longitudinal scanning of a radiation detector. The measurement of gas pressure inside long, small cross section, vacuum vessels is difficult due to the distance between the centre of the vacuum vessel and vacuum gauges (leading to a low vacuum conductance). The narrow beam of gamma Bremsstrahlung radiation is intercepted by scanning tungsten blades in the beam line front-end allowing a radiation shower to be detected outside the vacuum vessel proportional to the gas pressure in the corresponding storage ring straight section. A second detector mounted on rails can be moved over a length of 6.5 m parallel to the ESRF storage ring so as to localize regions of beam loss. The location of a scraper and narrow chamber entry and exit points are clearly resolved. (authors)

2005-01-01

265

Flow cytometric detection method for DNA samples  

Energy Technology Data Exchange (ETDEWEB)

Disclosed herein are two methods for rapid multiplex analysis to determine the presence and identity of target DNA sequences within a DNA sample. Both methods use reporting DNA sequences, e.g., modified conventional Taqman.RTM. probes, to combine multiplex PCR amplification with microsphere-based hybridization using flow cytometry means of detection. Real-time PCR detection can also be incorporated. The first method uses a cyanine dye, such as, Cy3.TM., as the reporter linked to the 5' end of a reporting DNA sequence. The second method positions a reporter dye, e.g., FAM, on the 3' end of the reporting DNA sequence and a quencher dye, e.g., TAMRA, on the 5' end.

Nasarabadi, Shanavaz (Livermore, CA); Langlois, Richard G. (Livermore, CA); Venkateswaran, Kodumudi S. (Livermore, CA)

2006-08-01

266

Flow cytometric detection method for DNA samples  

Energy Technology Data Exchange (ETDEWEB)

Disclosed herein are two methods for rapid multiplex analysis to determine the presence and identity of target DNA sequences within a DNA sample. Both methods use reporting DNA sequences, e.g., modified conventional Taqman.RTM. probes, to combine multiplex PCR amplification with microsphere-based hybridization using flow cytometry means of detection. Real-time PCR detection can also be incorporated. The first method uses a cyanine dye, such as, Cy3.TM., as the reporter linked to the 5' end of a reporting DNA sequence. The second method positions a reporter dye, e.g., FAM.TM. on the 3' end of the reporting DNA sequence and a quencher dye, e.g., TAMRA.TM., on the 5' end.

Nasarabadi,Shanavaz (Livermore, CA); Langlois, Richard G. (Livermore, CA); Venkateswaran, Kodumudi S. (Round Rock, TX)

2011-07-05

267

Method for detecting sophisticated cyber attacks  

Science.gov (United States)

A method of analyzing computer intrusion detection information that looks beyond known attacks and abnormal access patterns to the critical information that an intruder may want to access. Unique target identifiers and type of work performed by the networked targets is added to audit log records. Analysis using vector space modeling, dissimilarity matrix comparison, and clustering of the event records is then performed.

Potok, Thomas E. (Oak Ridge, TN)

2008-11-18

268

Method and apparatus for detecting an analyte  

Energy Technology Data Exchange (ETDEWEB)

We describe the use of coordination polymers (CP) as coatings on microcantilevers for the detection of chemical analytes. CP exhibit changes in unit cell parameters upon adsorption of analytes, which will induce a stress in a static microcantilever upon which a CP layer is deposited. We also describe fabrication methods for depositing CP layers on surfaces.

Allendorf, Mark D. (Pleasanton, CA); Hesketh, Peter J. (Atlanta, GA)

2011-11-29

269

Method for detecting fatigue crack in gears  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The most undesirable damage that can occur in gear units is crack in the tooth root as it often makes gear unit operation impossible. Monitoring vibrations can be used to detect defects. Time signals are acquired experimentally and afterwards. Different methods can be used to analyse them. The chang...

Belšak, Aleš; Flašker, Jože

270

Methods for Feature Detection in Point Clouds  

Digital Repository Infrastructure Vision for European Research (DRIVER)

This paper gives an overview over several techniques for detection of features, and in particular sharp features, on point-sampled geometry. In addition, a new technique using the Gauss map is shown. Given an unstructured point cloud, this method computes a Gauss map clustering on local neighborhood...

Weber, Christopher; Hahmann, Stefanie; Hagen, Hans

271

Method for detecting gas turbine engine flashback  

Energy Technology Data Exchange (ETDEWEB)

A method for monitoring and controlling a gas turbine, comprises predicting frequencies of combustion dynamics in a combustor using operating conditions of a gas turbine, receiving a signal from a sensor that is indicative of combustion dynamics in the combustor, and detecting a flashback if a frequency of the received signal does not correspond to the predicted frequencies.

Singh, Kapil Kumar; Varatharajan, Balachandar; Kraemer, Gilbert Otto; Yilmaz, Ertan; Lacy, Benjamin Paul

2012-09-04

272

A method for characterizing photon radiation fields  

Energy Technology Data Exchange (ETDEWEB)

Uncertainty in dosimetric and exposure rate measurements can increase in areas where multi-directional and low-energy photons (< 100 keV) exist because of variations in energy and angular measurement response. Also, accurate measurement of external exposures in spatially non-uniform fields may require multiple dosimetry. Therefore, knowledge of the photon fields in the workplace is required for full understanding of the accuracy of dosimeters and instruments, and for determining the need for multiple dosimeters. This project was designed to develop methods to characterize photon radiation fields in the workplace, and to test the methods in a plutonium facility. The photon field at selected work locations was characterized using TLDs and a collimated NaI(Tl) detector from which spatial variations in photon energy distributions were calculated from measured spectra. Laboratory results showed the accuracy and utility of the method. Field measurement results combined with observed work patterns suggested the following: (1) workers are exposed from all directions, but not isotropically, (2) photon energy distributions were directionally dependent, (3) stuffing nearby gloves into the glovebox reduced exposure rates significantly, (4) dosimeter placement on the front of the chest provided for a reasonable estimate of the average dose equivalent to workers` torsos, (5) justifiable conclusions regarding the need for multiple dosimetry can be made using this quantitative method, and (6) measurements of the exposure rates with ionization chambers pointed with open beta windows toward the glovebox provided the highest measured rates, although absolute accuracy of the field measurements still needs to be assessed.

Whicker, J.J.; Hsu, H.H. [Los Alamos National Lab., NM (United States); Hsieh, F.H.; Borak, T.B. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Radiological Health Sciences

1999-04-01

273

Method for an Image Sensor to Detect and Neutralize Pulsed Laser Jamming.  

Science.gov (United States)

This user report presents results of the project 'A Method for Detection of Laser Jamming.' Image sensors, sensitive to visual or IR radiation, are used in many military applications. However, a sensor of this type can be jammed by laser radiation. The la...

T. Gustafsson

1998-01-01

274

Test Report for Cricket Radiation Detection System Used In EPA Port Installations  

Energy Technology Data Exchange (ETDEWEB)

Oak Ridge National Laboratory conducted field radiological measurements at two port locations at the request of the Environmental Protection Agency (EPA). The radiological measurements were performed on five radiation detection systems at the port of Darrow, Louisiana and three systems at the port of Charleston, South Carolina. Darrow was visited on January 20-23, 2004 and Charleston on May 25, 2004. All tested systems are designed to detect radioactive material that might be present in scrap metals as the scrap is being unloaded from ships. All eight systems are commercially known as the Cricket and manufactured by RAD/COMM Systems. Each radiation detection system consists of a detector with two channels and a wireless transmitter, both mounted on the grapple, and a controller located in the crane cab. The cranes at both locations are operated by the Cooper T. Smith Company. The purpose of the radiological measurements was to evaluate the performance of the radiation detection systems in terms of their ability to detect elevated radiation levels, and to develop a routine testing method for all EPA Cricket systems.

Shourbaji, AA

2004-08-11

275

Method for the diffraction of terrestrial radiation, GAMMA radiation, etc  

International Nuclear Information System (INIS)

The patent claim concerns shielding against so-called earth radiation. These rays originate from water veins etc., cannot be defined any closer, and are supposed to cause injury to health. The author claims that shielding is possible with the aid of welding electrodes which have cores of nickel. (ORU/LN)

1975-01-01

276

Development of detection methods for irradiated foods  

Energy Technology Data Exchange (ETDEWEB)

To identify irradiated foods, studies have been carried out with electron spin resonance (ESR) spectroscopy on bone containing foods, such as chicken, pork, and beef. The intensity of the signal induced in bones increased linearly with irradiation doses in the range of 1.0 kGy to 5.0 kGy, and it was possible to distinguish between samples given low and high doses of irradiation. The signal stability for 6 weeks made them ideal for the quick and easy identification of irradiated meats. The analysis of DNA damage made on single cells by agarose gel electrophoresis (DNA 'comet assay') can be used to detect irradiated food. All the samples irradiated with over 0.3 kGy were identified to detect post-irradiation by the tail length of their comets. Irradiated samples showed comets with long tails, and the tail length of the comets increased with the dose, while unirradiated samples showed no or very short tails. As a result of the above experiment, the DNA 'comet assay' might be applied to the detection of irradiated grains as a simple, low-cost and rapid screening test. When fats are irradiated, hydrocarbons contained one or two fewer carbon atoms are formed from the parent fatty acids. The major hydrocarbons in irradiated beef, pork and chicken were 1,7-hexadecadiene and 8-heptadecene originating from leic acid. 1,7 hexadecadiene was the highest amount in irradiated beef, pork and chicken. Eight kinds of hydrocarbons were identified from irradiated chicken, among which 1,7-hexadecadiene and 8-heptadecen were detected as major compounds. The concentration of radiation-induced hydrocarbons was relatively constant during 16 weeks.

Yang, Jae Seung; Kim, Chong Ki; Lee, Hae Jung [Korea Atomic Energy Research Insitiute, Taejon (Korea, Republic of); Kim, Kyong Su [Chosun University, Kwangju (Korea, Republic of)

1999-04-01

277

Development of detection methods for irradiated foods  

International Nuclear Information System (INIS)

To identify irradiated foods, studies have been carried out with electron spin resonance (ESR) spectroscopy on bone containing foods, such as chicken, pork, and beef. The intensity of the signal induced in bones increased linearly with irradiation doses in the range of 1.0 kGy to 5.0 kGy, and it was possible to distinguish between samples given low and high doses of irradiation. The signal stability for 6 weeks made them ideal for the quick and easy identification of irradiated meats. The analysis of DNA damage made on single cells by agarose gel electrophoresis (DNA 'comet assay') can be used to detect irradiated food. All the samples irradiated with over 0.3 kGy were identified to detect post-irradiation by the tail length of their comets. Irradiated samples showed comets with long tails, and the tail length of the comets increased with the dose, while unirradiated samples showed no or very short tails. As a result of the above experiment, the DNA 'comet assay' might be applied to the detection of irradiated grains as a simple, low-cost and rapid screening test. When fats are irradiated, hydrocarbons contained one or two fewer carbon atoms are formed from the parent fatty acids. The major hydrocarbons in irradiated beef, pork and chicken were 1,7-hexadecadiene and 8-heptadecene originating from leic acid. 1,7 hexadecadiene was the highest amount in irradiated beef, pork and chicken. Eight kinds of hydrocarbons were identified from irradiated chicken, among which 1,7-hexadecadiene and 8-heptadecen were detected as major compounds. The concentration of radiation-induced hydrocarbons was relatively constant during 16 weeks

1999-01-01

278

Design of a Mobile Radiation Detection System for Seaports  

International Nuclear Information System (INIS)

[en] Pacific Northwest National Laboratory (PNNL) has developed a mobile radiation detection system for the U.S. Customs department. Based on the radiation detection instruments currently in use at many border crossings, the mobile radiation portal monitor (mRPM) consists of two Ludlum 4500-3000 detector panels, a package of sensors and a sensor integration module mounted to a medium duty truck chassis. The sensor package detects the presence of scanning targets (containers) and uses this to control operation of the detectors. The mRPM is designed to scan containerized cargo at seaports. A single mRPM can be driven past grounded or chassis-mounted containers (both sides of the container must be scanned for complete coverage), or a pair of mRPM systems can be parked opposite one another to form a relocatable portal. This rapidly reconfigurable system has proven to be very useful for targeted scanning of containers at multiple seaports. Since seaports are frequently space-constrained and contain few chokepoints, mobile systems that can be easily relocated allow customs operators to effectively scan cargo with minimal interference with the flow of commerce. Operators previously trained in the use of the stationary radiation portal monitors require minimal additional training to use the mRPM systems. The medium duty trucks employed are similar to one-ton crew cab pickup trucks, and a commercial driver's license is not required to operate them. In addition to successful deployments at seaports, the mRPM units have proven useful in other applications, such as preliminary characterization of rail cargo and targeted scanning at special events (political conventions)

2006-01-01

279

Design of a Mobile Radiation Detection System for Seaports  

Energy Technology Data Exchange (ETDEWEB)

Pacific Northwest National Laboratory (PNNL) has developed a mobile radiation detection system for the U.S. Customs department. Based on the radiation detection instruments currently in use at many border crossings, the mobile radiation portal monitor (mRPM) consists of two Ludlum 4500-3000 detector panels, a package of sensors and a sensor integration module mounted to a medium duty truck chassis. The sensor package detects the presence of scanning targets (containers) and uses this to control operation of the detectors. The mRPM is designed to scan containerized cargo at seaports. A single mRPM can be driven past grounded or chassis-mounted containers (both sides of the container must be scanned for complete coverage), or a pair of mRPM systems can be parked opposite one another to form a relocatable portal. This rapidly reconfigurable system has proven to be very useful for targeted scanning of containers at multiple seaports. Since seaports are frequently space-constrained and contain few chokepoints, mobile systems that can be easily relocated allow customs operators to effectively scan cargo with minimal interference with the flow of commerce. Operators previously trained in the use of the stationary radiation portal monitors require minimal additional training to use the mRPM systems. The medium duty trucks employed are similar to one-ton crew cab pickup trucks, and a commercial driver's license is not required to operate them. In addition to successful deployments at seaports, the mRPM units have proven useful in other applications, such as preliminary characterization of rail cargo and targeted scanning at special events (political conventions).

Baker, Carl P.

2006-02-11

280

Four-point vision range detecting device and detecting method  

UK PubMed Central (United Kingdom)

The invention relates to an instrument for detecting eyes, in particular to a portable type four-point visual field detecting device which can performing rapid glaucoma screening for a crowd, and a detecting method thereof. The instrument solves the problems that the volume of the prior hemispherical perimeter is large, the detecting time is long, and the novel frequency-doubling perimeter is expensive. The instrument adopts the technical proposal which adopts a planar visual field screen, a camera obscura with a visual field screen being sealed at one end and a gazing hole being arranged at the other end, and a lower jaw bracket installed in front of the camera obscura, wherein, the distance between the gazing hole and the center of the visual field screen is 330 mm, a central light emitting diode is arranged in the center of the visual field screen, four peripheral light emitting diodes are is arranged in the position of the intersection point of the visual angle circular of the gazing hole which is arranged inward for 15 degrees and a plus or minus 35 degree oblique line in a rectangular coordinate which takes the central light emitting diode as an initial point, a yellow background lamp is respectively arranged in the four corners of the visual field screen, and the detecting control circuit of the yellow background lamp comprises a single-chip microcomputer which is connected with each light emitting diode on the visual field screen by outputting and connected with an answer key by inputting, and a computer which is composed of an input keyboard, a display and a printer, which are connected through a serial communication interface.

ZHONGJIANG HE; YINGXIN LI; JIA WEI; WEIPING GAO

 
 
 
 
281

Human Portable Radiation Detection System Communications Package Evaluation  

International Nuclear Information System (INIS)

Testing and valuation of the Human Portable Radiation Detection System Communications Package for the US Coast Guard. The main components of the HCP field kit are an Archer Field PC(regsign) and an Iridium satellite phone, along with various charging components and cables. The Archer Field PC has an Enfora Global System for Mobile/General Packet Radio System (GSM/GPRS) wireless cellular modem installed via the compact flash (CF) port. The Iridium satellite phone has a serial communication interface attached. The Archer Field PC is running Windows Mobile(regsign) 5.0 operating system. Included Microsoft products are Excel(regsign) Mobile, PowerPoint(regsign) Mobile, Word(regsign) Mobile, and Internet Explorer(regsign) Mobile. There is an Outlook(regsign) Email program that can be accessed via sending a file or the Messaging link. The Cambridge Computer Corporation vxHpc program is installed to provide a Hyperterm-like software product. vxHpc supports multiple communication protocols. An AT and T SIM card was provided for the GSM wireless cellular modem. A check with AT and T determined the SIM card was not activated to provide cellular service. The Iridium satellite phone did not have a SIM card and has no service. The Archer Field PC boots into a HCP program, displaying the Main Menu. The following actions can be executed by selecting the appropriate box: Spectrum Download, Spectrum Transfer, and Admin Control. The Spectrum Download function uses the serial communication port to download data files from another device, such as a Radiation Isotope Identification Device (RIID). The Spectrum Transfer function uses either the installed wireless cellular modem or the Iridium satellite phone (attached to the serial communication port) to send data files to a computer modem at the Laboratories and Scientific Services (LSS). The Admin Control function allows entering phone numbers and data file deletion. PNNL recommends that DNDO (and/or CG) contact Sanmina and request a demo of the HCP Email data capability. The demo should include at a minimum three spectra data file attachments (background, known source, and unknown source) that are sent in the email package. The data should be sent using both included wireless cell phone hardware and the Iridium sat phone. The HCP has been optimized to operate on the Iridium Satellite Network, so that constraint needs to be factored into the selection of a service provider. It is also suggested that discussions with Sanmina work out the best method for CG personnel to use the HCP without requiring a separate email account for each HCP (e.g., similar to a BlackBerry using the member's email account), which should help make the HCP more user friendly.

2009-01-01

282

Cellular telephone-based radiation sensor and wide-area detection network  

Energy Technology Data Exchange (ETDEWEB)

A network of radiation detection instruments, each having a small solid state radiation sensor module integrated into a cellular phone for providing radiation detection data and analysis directly to a user. The sensor module includes a solid-state crystal bonded to an ASIC readout providing a low cost, low power, light weight compact instrument to detect and measure radiation energies in the local ambient radiation field. In particular, the photon energy, time of event, and location of the detection instrument at the time of detection is recorded for real time transmission to a central data collection/analysis system. The collected data from the entire network of radiation detection instruments are combined by intelligent correlation/analysis algorithms which map the background radiation and detect, identify and track radiation anomalies in the region.

Craig, William W. (Pittsburg, CA); Labov, Simon E. (Berkeley, CA)

2006-12-12

283

ESR detection of black pepper using standard addition method  

International Nuclear Information System (INIS)

[en] ESR techniques for studying the detection of radicals induced in gamma ray irradiated pepper were studied. The representative ESR spectrum of the pepper composed of a sextet centered at g=2.0, a single at the same g-value and a singlet at g=4.0. This reflects the evidence of three independent radicals in the pepper before irradiation. Upon gamma ray irradiation, a new pair of signals appeared. Using standard addition method for solid sample technique we prepared the experimental samples containing 2.0 - 20.0 w/w % irradiated black pepper. The progressive saturation behavior (PSB) at various microwave power levels indicated quite different relaxation behaviors of those signals. For the evaluation of radiation-induced radicals and irradiation effects we proposed a new protocol using the standard addition method. This would be called an advanced protocol for the detection of irradiated black pepper. (author)

2008-01-01

284

Method and system for detecting an explosive  

Energy Technology Data Exchange (ETDEWEB)

A method and system for detecting at least one explosive in a vehicle using a neutron generator and a plurality of NaI detectors. Spectra read from the detectors is calibrated by performing Gaussian peak fitting to define peak regions, locating a Na peak and an annihilation peak doublet, assigning a predetermined energy level to one peak in the doublet, and predicting a hydrogen peak location based on a location of at least one peak of the doublet. The spectra are gain shifted to a common calibration, summed for respective groups of NaI detectors, and nitrogen detection analysis performed on the summed spectra for each group.

Reber, Edward L. (Idaho Falls, ID); Rohde, Kenneth W. (Idaho Falls, ID); Blackwood, Larry G. (Bozeman, MT)

2010-12-07

285

A fast, simple method for screening radiation susceptibility genes by RNA interference  

International Nuclear Information System (INIS)

Radiotherapy can cause unacceptable levels of damage to normal tissues in some cancer patients. To understand the molecular mechanisms underlying radiation-induced physiological responses, and to be able to predict the radiation susceptibility of normal tissues in individual patients, it is important to identify a comprehensive set of genes responsible for radiation susceptibility. We have developed a simple and rapid 96-well screening protocol using cell proliferation assays and RNA interference to identify genes associated with radiation susceptibility. We evaluated the performance of alamarBlue-, BrdU-, and sulforhodamine B-based cell proliferation assays using the 96-well format. Each proliferation assay detected the known radiation susceptibility gene, PRKDC. In a trial screen using 28 shRNA vectors, another known gene, CDKN1A, and one new radiation susceptibility gene, ATP5G3, were identified. Our results indicate that this method may be useful for large-scale screens designed to identify novel radiation susceptibility genes.

2005-08-12

286

Geiger-mueller radiation detector with means for detecting and indicating the existence of radiation overload  

Energy Technology Data Exchange (ETDEWEB)

When subjected to radiation overload existing geiger-mueller counters may give an erroneously low reading, resulting in possible hazard to personnel. The instant invention discloses simple and inexpensive apparatus to remedy this dangerous shortcoming. Depending on the geometry of the detector tube, two possible failure modes have been identified, and circuitry is disclosed to detect the existence of these respective failure modes. The disclosed apparatus indicates the absence of an overload condition, in addition to signaling, by both visible and audible means, the existence of excessive radiation that might result in erroneously low reading of the geiger-mueller counter.

Kovacs, T.; Mills, A.P.; Pfeiffer, L.N.

1981-04-07

287

Method of measuring blood flow by radiation  

International Nuclear Information System (INIS)

A method of measuring relative blood flow through at least a part of the body using penetrating radiation comprises transmitting a plurality of rays at an initial angle or initial mean angle through a planar slice of the body to define a first set of rays, transmitting a plurality of further sets of rays at angles or mean angles different from each other and from the initial angle or initial mean angle through the same planar slice of the body to define by the intersection of all such rays a two-dimensional matrix of elements of the body in the slice, measuring for each ray emerging from the body a number of over the period of time at least equal to a pulse interval representing the momentary sum of the transmissions or absorptions of the element of the body intersected by the ray, determining from the momentary signals momentary signals a difference signal representing the maximum difference between the momentary signals for each ray over the period of time, deriving sets of discrete difference signals corresponding to the sets of rays, the difference signals being indicative of the transmission or absorption of blood flowing through each element of the body in the matrix, and calculating from the difference signals resultant signals representing the transmissions or absorptions due to blood flow in the elements of the matrix. These resultant signals may be visually depicted on a cathode ray tube display, as a digital print-out, or as a photograph. 30 claims, 8 figures

1977-01-01

288

Monte Carlo method in radiation transport problems  

International Nuclear Information System (INIS)

[en] In neutral radiation transport problems (neutrons, photons), two values are important: the flux in the phase space and the density of particles. To solve the problem with Monte Carlo method leads to, among other things, build a statistical process (called the play) and to provide a numerical value to a variable x (this attribution is called score). Sampling techniques are presented. Play biasing necessity is proved. A biased simulation is made. At last, the current developments (rewriting of programs for instance) are presented due to several reasons: two of them are the vectorial calculation apparition and the photon and neutron transport in vacancy media[fr] Dans l'etude des problemes de transport de rayonnements neutres (neutrons photons), deux grandeurs sont importantes: le flux dans l'espace de phases et la densite de particules entrant en collision. Resoudre le probleme par Monte Carlo consiste entre autres a construire un processus statistique (appele jeu) et attribuer une valeur numerique a une variable x (cette attribution s'appelle score). Les techniques d'echantillonnage sont presentees. La necessite du biaisage du jeu est demontree. Une simulation biaisee est realisee. Enfin les developpements en cours (reecriture de programmes) sont presentes, necessaires pour plusieurs raisons dont l'apparition des calculs vectoriels, et le transport de photons et neutrons dans les milieux lacunaires

1986-01-01

289

Influence of ionising radiation on macromolecular components of wheat; possible use in detecting irradiated wheat  

Energy Technology Data Exchange (ETDEWEB)

The treatment of food by ionising radiation is already permitted by many governments and is under consideration by many others. Cereal are irradiated as a means of disinfestation, this study investigates the effects of such processing on the components of wheat and examines using such radiation induced changes to detect irradiation. Wheat has been irradiated with ionising radiation in the dose range up to 1 kGy. The rheological properties of doughs prepared from this irradiated wheat have been investigated. An immunological assay has been employed to investigate the effect of wheat irradiation on the integrity of gliadin. A method has been developed for the routine isolation of DNA from wheat. Radiation-induced disruption of the DNA double helix has been assessed in DNA extracted from irradiated wheat and calf thymus DNA irradiated in aqueous solution. (author).

Jabir, A.-W.Sh.

1992-01-01

290

Evaluation of potassium nitrate for gamma-radiation detection  

Energy Technology Data Exchange (ETDEWEB)

Pellets of potassium nitrate (KNO{sub 3}) were evaluated to verify if they can be employed as dosimetric material for high dose measurements in routine use of radiation monitoring in radiation processing plants. The spectrophotometry in the visible region was used as detection technique. Pellets of KNO{sub 3} were dissolved in pure water to allow the optical absorption measurements before and after irradiation with {sup 60} Co gamma radiation source, calibrated with Fricke solution reference dosimeter. The absorption spectrum of the KNO{sub 3} solution was investigated in the wavelength region between 500 and 600 nm to determine the maximum absorption wavelength. Dosimetric properties such as dose rate dependence in the interval between 0.059 and 3.82 kGy/h, angular radiation incidence dependence between 0 and 90 degrees and dose response in the range between 1-150 kGy were investigated. The obtained results show the proposed dosimetric material can be useful in high dose measurements. (author)

Galante, Ana Maria Sisti; Rzyski, Barbara M.; Campos, Leticia L. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)]. E-mail: sgalante@net.ipen.br

2001-07-01

291

INSECT MONITORING DEVICE AND METHOD OF DETECTION  

UK PubMed Central (United Kingdom)

The invention relates to a bed bug detection device (10) comprising a refuge (16) which elicits a taxis response from bed bugs and a non-trapping indicator surface (18), on which the bed bugs may leave indicators of their presence, such as faecal matter or cast skins. The refuge is positioned in close proximity to said non-trapping indicator surface such that the bed bugs can leave an indicator of their presence as they travel across the indicator surface on their way to or from the refuge. Preferably the non-trapping indicator surface takes the form of a skirt which surrounds a refuge made of corrugated paper. The invention also provides a passive method of detecting the presence of bed bugs without their capture by detecting the presence of indicators rather than the bed bugs per se.

CAIN DAVID

292

Hough transform methods used for object detection  

International Nuclear Information System (INIS)

The Hough transform (HT) is a robust parameter estimator of multi-dimensional features in images. The HT is an established technique which evidences a shape by mapping image edge points into a parameter space. The HT is technique which is used to isolate curves of a give shape in an image. The classical HT requires that the curve be specified in some parametric from and, hence is most commonly used in the detection of regular curves. The HT has been generalized so that it is capable of detecting arbitrary curved shapes. The main advantage of this transform technique is that it is very tolerant of gaps in the actual object boundaries the classical HT for the detection of line , we will indicate how it can be applied to the detection of arbitrary shapes. Sometimes the straight line HT is efficient enough to detect features such as artificial curves. The HT is an established technique for extracting geometric shapes based on the duality definition of the points on a curve and their parameters. This technique has been developed for extracting simple geometric shapes such as lines, circles and ellipses as well as arbitrary shapes. The HT provides robustness against discontinuous or missing features, points or edges are mapped into a partitioned parameter of Hough space as individual votes where peaks denote the feature of interest represented in a non-analytically tabular form. The main drawback of the HT technique is the computational requirement which has an exponential growth of memory space and processing time as the number of parameters used to represent a primitive increases. For this reason most of the research on the HT has focused on reducing the computational burden for extracting of arbitrary shapes under more general transformations include a overview of describing the methods for the detection image processing programs are frequently required to detect and particle classification in an industrial setting, a standard algorithms for this detection lines, circles, and ellipses shapes in image by using the HT. The methods and algorithms working to detect the objects, in which captured from 3-dimension real image to 2-dimension image. (Author)

2001-01-01

293

A silicon spectrometer for transition radiation detection for space applications  

CERN Document Server

A novel design of a Transition Radiation Detector, based on Silicon Microstrip Detectors, is presented. Owing to the relatively high ionization energy release in semiconductor material (a few hundred kev), a magnetic field should be used to separate the radiating particle from TR X-ray photons. We have developed a full Monte-Carlo code to study in detail the performance of this detector such as bending power, strip pitch, charge sharing, and detection efficiency. We also present the results obtained with a small prototype exposed to an electron/pion beam at CERN PS. The particle identification capability allows the distinction of hadron from electrons up to 40 GeV/c and the spectrometer rigidity is almost 40 GV.

Brigida, M; Fusco, P; Gargano, F; Giglietto, N; Giordano, F; Loparco, F; Mazziotta, M N; Prest, M; Rainó, S; Spinelli, P; Vallazza, E

2003-01-01

294

Neutron and/or gamma radiation detecting system  

International Nuclear Information System (INIS)

A large reception surface for the radiation to be detected is formed on a body of scintillation material (ZnS-AG with B matrix) which is adapted to convert neutron or gamma radiation into light energy. A large number of fiber light conductors is embedded in the body of scintillation material such that the fibers extend essentially parallel and fully across the reception surface of the body of scintillation material. The light energy, upon propagation along the fiber light conductors, is coupled into the conductors along the surface of the fibers which are unisotropic. This arrangement permits the use of unisotropic light conductor systems which provide for a separation of light collecting and light transmitting functions which results in a substantial reduction of light absorption losses during light transmission so that most of the light energy coupled into the fiber light conductors reaches the optoelectronic amplifier coupled to the end of the light conductors. (orig./HP)

1983-09-30

295

The Photon Haystack and Emerging Radiation Detection Technology  

Energy Technology Data Exchange (ETDEWEB)

The resources devoted to interdicting special nuclear materials have increased considerably over the last several years in step with growing efforts to counter nuclear proliferation and nuclear terrorism. This changing landscape has led to a great deal of current research and development that aims to improve the effectiveness of technology now deployed worldwide. The interdiction of special nuclear materials is most commonly addressed by detecting and characterizing emitted gamma rays, but modest signature emissions can be obscured by attenuating material and must be differentiated from large and highly variable environmental background. While this makes gamma-ray detection of special nuclear materials a daunting technical challenge, a host of new detection technologies are now emerging. We thus review special nuclear material signatures, the physics of detection approaches, and detection performance metrics. The use of benchmark materials aids our discussion and comparison of detection methods.

Runkle, Robert C.; Smith, Leon E.; Peurrung, Anthony J.

2009-09-15

296

Leak detection implementation; Modeling and tuning methods  

Energy Technology Data Exchange (ETDEWEB)

This paper contains an overview of the Williams Pipe Line computerized dynamic leak detection system, including the basic calculation methods used in the system, instrumentation support requirements, and various operational situations encountered during the implementation process. Special emphasis is given to enhanced modeling techniques required for complex pipeline configurations. Sample performance test results are presented with a discussion focused primarily on the system response time.

Griebenow, G.; Mears, M. (Williams Pipe Line Co., Tulsa, OK (US))

1989-06-01

297

SARA (Spectroscopic Ambient Radiation Detection) Spectroscopic Monitoring Systems for Online Environmental Radiation Monitoring Edition 2008  

International Nuclear Information System (INIS)

In the wake of a nuclear incident, it is essential that you can react promptly and provide a completely reliable assessment of the radiological situation. First and foremost, it is vital that your radiation early warning system can automatically detect any man-made isotopes in the environment and identify any changes in the composition of the ambient radiation. Before appropriate countermeasures can be implemented, it is crucial that authorities have accurate information about the type of contamination and its dispersion. TechniData's spectroscopic online monitoring system will improve your existing monitoring systems, provide important information about the composition of ambient radiation during an incident, and therefore help you to make the right decisions

2009-01-01

298

Electromagnetic radiation. Variational methods, waveguides and accelerators  

International Nuclear Information System (INIS)

This is a graduate level textbook on the theory of electromagnetic radiation and its application to waveguides, transmission lines, accelerator physics and synchrotron radiation. It has grown out of lectures and manuscripts by Julian Schwinger prepared during the war at MIT's Radiation Laboratory, updated with material developed by Schwinger at UCLA in the 1970s and 1980s, and by Milton at the University of Oklahoma since 1994. The book includes a great number of straightforward and challenging exercises and problems. It is addressed to students in physics, electrical engineering, and applied mathematics seeking a thorough introduction to electromagnetism with emphasis on radiation theory and its applications. A hardcover edition containing additionally the reprints of more than 15 papers by Schwinger on these topics is available separately. (orig.)

2006-01-01

299

Improved method for detection of starch hydrolysis  

Energy Technology Data Exchange (ETDEWEB)

A new starch hydrolysis detection method which does not rely on iodine staining or the use of color-complexed starch is described. A linear relationship was obtained with agar-starch plates when net clearing zones around colonies of yeasts were plotted against enzyme levels (semilogarithm scale) produced by the same yeast strains in liquid medium. A similar relationship between starch clearing zones and alpha-amylase levels from three different sources was observed. These observations suggest that the method is useful in mutant isolations, strain improvement programs, and the prediction of alpha-amylase activities in culture filtrates or column effluents. (Refs. 18).

Ohawale, M.R.; Wilson, J.J.; Khachatourians, G.G.; Ingledew, W.M.

1982-09-01

300

Detection Method of TOXOPLASMA GONDII Tachyzoites  

Science.gov (United States)

Tachyzoites are considered to be the most important stage of Toxoplasma gondii which causes toxoplasmosis. T. gondii is, an obligate intracellular parasite which infects a wide range of cells. The present study was designed to develop a method for an early detection of T. gondii tachyzoites. The method comprised of a binding assay which was analyzed using principal component and cluster analysis. Our data showed that glycoconjugates GC1, GC2, GC3 and GC10 exhibit a significantly higher binding affinity for T. gondii tachyzoites as compared to controls (T. gondii only, PAA only, GC 1, 2, 3, and 10 only).

Eassa, Souzan; Bose, Chhanda; Alusta, Pierre; Tarasenko, Olga

2011-06-01

 
 
 
 
301

A new IQ detection method for LLRF  

Science.gov (United States)

Digital LLRF technology has been widely used in new generation particle accelerators. IF quadrature sampling is a common method for amplitude and phase detection. Many strategies, which obey the same rule of fsample=(M/N)fIF (M/N is a rational number), have been proposed to reduce the effects of spectrum aliasing. However, we found that M/N does not need to be a rational number according to Shannon's theorem. Therefore, we propose a new IQ detection method in this paper. This method is based on a special IIR filter which is derived from an RLC circuit. The unique characteristic of the method is that the value of fIF is independent of the value of fsample. We have set up an experimental platform to verify our method. A 122.88 MHz sampling clock is used to sample a 3 MHz IF signal. The DDS and PI control techniques are used to realize the closed-loop control. Results show that the stability of the system is within ± 0.05% (peak to peak) for the amplitude, and with ±0.03° (peak to peak) for the phase in 5 h.

Qiu, Feng; Gao, Jie; Lin, Hai-ying; Liu, Rong; Ma, Xin-peng; Sha, Peng; Sun, Yi; Wang, Guang-wei; Wang, Qun-yao; Xu, Bo; Zeng, Ri-hua

2012-05-01

302

Improvements in or relating to radiation detection arrangements  

International Nuclear Information System (INIS)

A radiation detection arrangement is described that that comprises a number of scintillator devices, and a single multi-channel photomultiplier tube. Light from the scintillator devices is incident on the photocathode through an entrance window in the tube and multiplier entrance separating means are provided whereby light from each of the devices is made to be incident upon the channel entrances of photomultiplier tube. Various geometrical forms for the scintillator devices are described. This arrangement avoids the use of large number of small photomultiplier tubes, which is expensive and gives rise to difficulties in stacking the tubes in closely spaced side-by-side relationship. (U.K.)

1977-01-01

303

Thermoplastic elastomer IPNs using radiation methods  

International Nuclear Information System (INIS)

Full text: Styrene swollen, cross-linked TPEs can be thermally processed to give a new class of sequential interpenetrating polymer network (IPN). There are however certain limitations with this procedure, particularly in relation to the thermally initiated polymerization, including: the microscopic texture of the original TPE may be modified, the butadiene component of the TPE may thermally oxidize, safety concerns with monomer vapors at elevated temperatures exist; the concentration of monomer in the swollen TPE may change and be uneven. The method cannot be readily extended to the use of a volatile second monomer, such as butadiene or isoprene. Gamma radiation crosslinking allows uniform penetration and ambient temperatures. We used the multifunctional cross-linker, TMPTA, as this has been shown to work well under these conditions with styrene. Peroxide cross-linked Solprene 475 was swollen in inhibitor-free styrene containing 0, 10 and 33% by weight TMPTA and irradiated at 3 kGy/hr for total doses ranging typically from 50 to 1000 kGy. Hardnesses (Durometer Shore D) increased from 50 to plateau at about 65 units, and tensile strengths are ? 10-15 MPa. Initial data indicates breaking strains in the range 20 to 90%. A key observation is that the products were of uniform hardness and appearance, in contrast to many of the thermally prepared materials in the past, which also showed yellowing due to polybutadiene oxidation. Products were stained with osmium tetroxide, ultramicrotomed and observed by TEM. The morphologies of the new materials are more uniform than before, with less evidence of orientation. The previous structures were typically of swollen styrene rich rods in a butadiene matrix, whereas here the TEMs reveal a spongelike texture

2000-01-01

304

Nick translation detection in situ of cellular DNA strand break induced by radiation  

Energy Technology Data Exchange (ETDEWEB)

DNA strand break in HeLa cells induced by radiation was detected using the in situ nick translation method. The cells were exposed to radiation of 3, 6, 12, 18, and 24 Gy in Lab-Tek tissue culture chamber/slides and were fixed with ethanol/acetic acid on the slide glass. The break sites in DNA were translated artificially in the presence of Escherichia coli DNA polymerase I and (/sup 3/H)-labeled dTTP. Autoradiographic observation was made of the level of break sites in the DNA. The DNA strand break appeared even with a 3 Gy exposure, increased 8.6 times at 24 Gy compared with the control cells, and this level correlated reciprocally to change in cell viability. This nick translation method provides a rapid in situ assay for determining radiation-induced DNA damage of cultured cells, in a semi-quantitative manner.

Maehara, Y.; Anai, H.; Kusumoto, T.; Sakaguchi, Y.; Sugimachi, K.

1989-01-01

305

Nick translation detection in situ of cellular DNA strand break induced by radiation  

International Nuclear Information System (INIS)

DNA strand break in HeLa cells induced by radiation was detected using the in situ nick translation method. The cells were exposed to radiation of 3, 6, 12, 18, and 24 Gy in Lab-Tek tissue culture chamber/slides and were fixed with ethanol/acetic acid on the slide glass. The break sites in DNA were translated artificially in the presence of Escherichia coli DNA polymerase I and [3H]-labeled dTTP. Autoradiographic observation was made of the level of break sites in the DNA. The DNA strand break appeared even with a 3 Gy exposure, increased 8.6 times at 24 Gy compared with the control cells, and this level correlated reciprocally to change in cell viability. This nick translation method provides a rapid in situ assay for determining radiation-induced DNA damage of cultured cells, in a semi-quantitative manner

1989-01-01

306

Nuclear radiation detection via the deflection of pliable microstructures  

International Nuclear Information System (INIS)

[en] The feasibility of detecting single quanta of radiation via mechanical deflection is examined. When a particle strikes an object, momentum is transferred to the impacted body. The resulting body motion can be correlated to the energy of the incident particle. Microelectronic fabrication techniques are used to build the sensing microstructures. Typical levers which have been fabricated have dimensions of width=1 ?m, length=5 ?m, and thickness=0.05 ?m. Linear beam deflection theory is used to model the vibration of the levers. Theoretical pulse height distributions demonstrate that the signals from heavy-ion impacts are measurable, but those from light-ion collisions are swamped by the thermal noise contribution. Thus, if light ions are to be detected, then the effects of thermal noise must be reduced

1999-02-11

307

A detection system for clinical breast tomography with synchrotron radiation  

Energy Technology Data Exchange (ETDEWEB)

The goal of the MAmmographic and Tomographic Imaging with Silicon detectors and Synchrotron radiation at Elettra (MATISSE) project is to develop a detection system in order to perform in vivo breast tomographic examination at Elettra, the Trieste synchrotron facility. The detection system consists of a silicon microstrip detector used in edge on configuration with single photon counting read out electronics. Due to both high efficiency of the detector and the possibility of selecting the most suitable energy, the dose delivered for a tomographic examination is comparable to the one delivered in planar conventional mammography. The first detector prototype has been assembled and the preliminary tests gave promising results for what concerns both the incoming rate response and the contrast resolution. Planar images of a mammographic test object have been collected, while tomographic images will be acquired with a new prototype during the next spring (2004)

Bergamaschi, A. [Dipartimento di Fisica, Universita degli Studi di Trieste, Trieste (Italy) and INFN Sezione di Trieste, Trieste (Italy)]. E-mail: bergamaschi@ts.infn.it; Dreossi, D. [Dipartimento di Fisica, Universita degli Studi di Trieste, Trieste (Italy); INFN Sezione di Trieste, Trieste (Italy); Longo, R. [Dipartimento di Fisica, Universita degli Studi di Trieste, Trieste (Italy); INFN Sezione di Trieste, Trieste (Italy); Olivo, A. [Dipartimento di Fisica, Universita degli Studi di Trieste, Trieste (Italy); INFN Sezione di Trieste, Trieste (Italy); Pani, S. [Dipartimento di Fisica, Universita degli Studi di Trieste, Trieste (Italy); INFN Sezione di Trieste, Trieste (Italy); Venanzi, C. [Dipartimento di Fisica, Universita degli Studi di Trieste, Trieste (Italy); INFN Sezione di Trieste, Trieste (Italy); Castelli, E. [Dipartimento di Fisica, Universita degli Studi di Trieste, Trieste (Italy); INFN Sezione di Trieste, Trieste (Italy)

2004-12-11

308

Ticor-based scintillation detectors for detection of mixed radiation  

CERN Multimedia

Detection of mixed radiation of thermal neutrons and gamma-rays have been realized using a new ceramic material based on small-crystalline long-wave scintillator alpha-Al sub 2 O sub 3 :Ti (Ticor) and lithium fluoride. Characteristics are presented for scintillators with Si-PIN-PD type photoreceivers and PMT under sup 2 sup 3 sup 9 Pu alpha-particles, sup 2 sup 0 sup 7 Bi internal conversion electrons,as well as sup 2 sup 4 sup 1 Am and sup 1 sup 3 sup 7 Cs gamma-quanta. Detection efficiency of thermal neutron is estimated for composite materials based on Ticor and lithium fluoride.

Litvinov, L A; Kolner, V B; Ryzhikov, V D; Volkov, V G; Tarasov, V A; Zelenskaya, O V

2002-01-01

309

Novel Methods of Hydrogen Leak Detection  

International Nuclear Information System (INIS)

With the advent of the fuel cell technology and a drive for clean fuel, hydrogen gas is emerging as a leading candidate for the fuel of choice. For hydrogen to become a consumer fuel for automotive and domestic power generation, safety is paramount. It is, therefore, desired to have a method and system for hydrogen leak detection using odorant which can incorporate a uniform concentration of odorant in the hydrogen gas, when odorants are mixed in the hydrogen storage or delivery means. It is also desired to develop methods where the odorant is not added to the bulk hydrogen, keeping it free of the odorization additives. When odorants are not added to the hydrogen gas in the storage or delivery means, methods must be developed to incorporate odorant in the leaking gas so that leaks can be detected by small. Further, when odorants are not added to the stored hydrogen, it may also be desirable to observe leaks by sight by discoloration of the surface of the storage or transportation vessels. A series of novel solutions are proposed which address the issues raised above. These solutions are divided into three categories as follows: 1. Methods incorporating an odorant in the path of hydrogen leak as opposed to adding it to the hydrogen gas. 2. Methods where odorants are generated in-situ by chemical reaction with the leaking hydrogen 3. Methods of dispensing and storing odorants in high pressure hydrogen gas which release odorants to the gas at a uniform and predetermined rates. Use of one or more of the methods described here in conjunction with appropriate engineering solutions will assure the ultimate safety of hydrogen use as a commercial fuel. (authors)

2006-01-01

310

Radiation detector and method of opaquing the mica window  

Energy Technology Data Exchange (ETDEWEB)

An improved particle detection tube is disclosed including a method for applying a radiation transparent electrically non-conductive, opaque to ultraviolet light coating to the mica window of the tube. The coating reduces erroneous counts by preventing arcing between the tube anode and window. A purified mineral bituminous hydrocarbon based wax coating is applied to the mica window by cleaning the window with a hydrocarbon or chlorinated solvent rinsing with isopropyl alcohol drying the window dissolving 4 to 20 milligrams of purified bituminous hydrocarbon based wax in 1 to 2 milliliters of a hydrocarbon or chlorinated solvent on the window, and rotating the tube until the solvent evaporates to produce a film of the wax thereon.

Morris, H.; Christianson, C.

1983-10-11

311

Radiation detection using long lasting phosphor (luminous paint)  

International Nuclear Information System (INIS)

The detection characteristic of long lasting phosphor (LLP, SrAl2O4; Eu2+, Dy3+) has been studied in ?, ?, and ? radiation field. It was found that the total luminous intensity of LLP had linear response over a wide range of absorbed energy for all radiations. The luminous intensity showed significant temperature dependence and the peak intensity was observed near room temperature. The thermoluminescence glow curve suggested that the luminosity of LLP consisted of 4-components and the time profile of LLP luminescence was found to be described by a simple sum of these components. The Arrhenius plot of escape rates calculated from the afterglow region provided the activation energies of escape process form trap levels and these values were ranged from 24 meV to 0.34 eV, which corresponded to the escape rates of 0.8-8.3x103 s-1 at room temperature. The trapping ratios to the 4 traps were also determined from afterglow ratio curves and had no temperature dependence. These trapping ratios were ranging from 0.16 to 0.35 for ? and ? irradiation and slightly different values were obtained for ? rays. The experimental time profile can be fitted within experimental error using the trapping ratios and escape rates. Various applications of LLP will be expected as radiation detectors, especially as 2-dimensional imaging devices. (author)

2000-01-01

312

Apparatus and method for detecting an analyte  

UK PubMed Central (United Kingdom)

An apparatus ( 100 ) and method ( 400 ) for detecting the presence of one or more chemical contaminants in/on a plurality of items, e.g., cork stoppers ( 110 ), using nose chips ( 310 ). The apparatus utilizes detection sensor electronics ( 225 ) that are separate from the nose chips such that each nose chip can be either reused or discarded after use. The apparatus moves the nose chips and the cork stoppers independently to align the cork stopper and a corresponding nose chip with one another. The testing apparatus uses multiple sensor units ( 135 ) to simultaneously test multiple cork stoppers for chemical contaminants (e.g., TCA). The invention provides a low-cost, reliable process for testing 100% of cork stoppers in a fast and cost-effective manner that is scalable to the general consumer product market.

HEAD MICHAEL S; CRONIN JOHN; BURROWS MARK; TIMBLIN CYNTHIA

313

Molecular methods for rapid detection of aneuploidy.  

Science.gov (United States)

Rapid molecular biological methods for prenatal diagnosis of the most common aneuploidies, collectively known as rapid aneuploidy testing, are compared in this review. We discuss methodological problems and limitations of these various methods. All these techniques are believed to be accurate and carry a low risk of misdiagnosis, but they differ in terms of labour-intensity and amenability to automation and high throughput testing. The question how to apply them safely and economically in a clinical setting has not been answered yet. The discussed techniques are so far not used as stand-alone tests, but some of them are routinely applied as a preliminary test that shortens the waiting time for classic cytogenetic karyotyping. In the future, mainly because of economical reasons, these methods may replace cytogenetics in the category of patients who make up the majority of those currently offered prenatal karyotyping: patients with moderately increased risk and no abnormalities detected by ultrasound. PMID:15876689

Dudarewicz, Lech; Holzgreve, Wolfgang; Jeziorowska, Anna; Jakubowski, Lucjusz; Zimmermann, Bernhard

2005-01-01

314

Molecular methods for rapid detection of aneuploidy.  

UK PubMed Central (United Kingdom)

Rapid molecular biological methods for prenatal diagnosis of the most common aneuploidies, collectively known as rapid aneuploidy testing, are compared in this review. We discuss methodological problems and limitations of these various methods. All these techniques are believed to be accurate and carry a low risk of misdiagnosis, but they differ in terms of labour-intensity and amenability to automation and high throughput testing. The question how to apply them safely and economically in a clinical setting has not been answered yet. The discussed techniques are so far not used as stand-alone tests, but some of them are routinely applied as a preliminary test that shortens the waiting time for classic cytogenetic karyotyping. In the future, mainly because of economical reasons, these methods may replace cytogenetics in the category of patients who make up the majority of those currently offered prenatal karyotyping: patients with moderately increased risk and no abnormalities detected by ultrasound.

Dudarewicz L; Holzgreve W; Jeziorowska A; Jakubowski L; Zimmermann B

2005-01-01

315

Method for detecting hematopoietic stem cells  

UK PubMed Central (United Kingdom)

The present invention provides an isolated nucleic acid encoding KIAA0918, an isolated nucleic acid that hybridizes under high stringency conditions to a nucleic acid that is complementary to a nucleic acid encoding KIAA0918, a purified KIAA0918 protein, a purified protein encoded by a nucleic acid that hybridizes under high stringency conditions to a nucleic acid that is complementary to a nucleic acid encoding KIAA0918, a method of making KIAA0918 protein, an antibody specific for KIAA0918, a method for producing an antibody specific for KIAA0918 protein, a vector comprising a nucleic acid encoding KIAA0918, and a host cell transformed with a vector comprising a nucleic acid encoding KIAA0918. Also provided are methods for detecting the presence of and isolating hematopoietic stem cells in a heterogeneous cell suspension and for assessing gene expression in a tissue sample.

BELYAVSKY ALEXANDER; SHMELKOV SERGEY; VISSER JAN

316

Radiation methods in dairy production and processing  

International Nuclear Information System (INIS)

Various uses of radiotracers and radiation in dairy technology are described. In dairy production, radiotracers are used for studying: (1) rumen metabolism leading to protein synthesis (2) total body water, blood volume and sodium (3) minerals metabolism (4) relation between climatic stress and thyroid functioning of dairy animals (5) volume of milk in mammary glands (6) hormone level in dairy animals and (7) spermatozoa metabolism. In dairy processing, radiotracers are used for studying: (1) compositional analysis of milk and milk products and (2) efficiency of cleaning agents for cleaning dairy equipment. Ionizing radiation is used for: (1) preservation of milk and milk products and (2) sterilization of packaging materials. Radiation source has been used to monitor the over-run in ice-cream and the fill control for fluid in papar cartons. (M.G.B.).

1975-01-01

317

Development of detection methods for irradiated foods - Development of detection method for radiolytic products of irradiated foods  

Energy Technology Data Exchange (ETDEWEB)

Meats, nuts, legumes and cereals were irradiated with {sup 60}Co {gamma}-ray. The detection methods included the fat extraction from samples, isolation of hydrocarbons and 2-alkylcyclobutanones by florisil column chromatography and analyses of GC-FID and GC/MS analyzers. Concentrations of hydrocarbons and 2-clobutanones increased with the irradiation dose in meat, nuts, legumes and cereals. In nuts (sesame seeds, black sesame seeds, perilla seeds, pine nuts and peanuts), legumes (white beans, black soybeans, yellow bean sprout soybeans, mouse-eyed soybeans, mung beans, kidney beans and small red beans) and cereals (brown rice, corns and wheat), 8-heptadecene and 1,7-hexadecadiene originated from oleic acid and 6,9-heptadecadiene and 1,7,10-hexadecatriene induced from linoleic acids were the major hydrocarbons due to the composition of fatty acids. Concentrations of radiation-induced hydrocarbons in nuts were slightly reduced and hydrocarbons were still significantly detectable, during 6 months at -18 deg. C. In meats and nuts, 2-(5'-tetradecenyl)cyclobutanone formed from oleic acid was found in most. 2-Dodecylcyclobutanone was detected in a large amount. The concentrations of radiation-induced 2-alkylcyclobutanones in meats slightly decreased, but relatively constant during 6 months at -18 deg. C. 62 refs., 45 figs., 25 tabs. (Author)

Kim, Kyong Su; Lee, Eun Ryong; Hong, Hae Jung [Chosun University, Kwangju (Korea)

2000-07-01

318

A study of the effects of scattered radiation on radiographic quality and methods of elimination of such radiation  

International Nuclear Information System (INIS)

Many mechanical parts are subjected to stresses and strains that may eventually lead to their failure. In order to prevent the costly delays associated with equipment down-time, many parts have to be tested for weaknesses and defects when machinery is constructed or dismantled for maintenance. These procedures are known as Non-Destructive Testing (NDT) methods. Five types of non-destructive testing methods routinely used are radiographic testing, ultrasonic testing, magnetic particle inspection, liquid penetrant testing and eddy current testing. Out of these five techniques industrial radiography plays an important role in non-destructive testing to reveal interior defects in materials. In radiography almost two-thirds of the radiation reaching the film is scattered radiation which does not form the image of defects. Scattered radiation generated inside and outside a material has a very large effect on sensitivity of flaw detection since it reduces image contrast. The effect of scattered radiation on radiographic sensitivity and the possibilities of measuring scattered radiation has been studied. A number of methods to reduce the effect of such radiation have been considered and tested. (author)

1998-01-01

319

?-radiation detected Li diffusion in the fast ionic conductor Li3N  

International Nuclear Information System (INIS)

The method of ?-radiation detected nuclear magnetic resonance (?-NMR) was applied to 8Li in a 7Li3N single crystal. From NMR signals and spin-lattice relaxation rates the activation enthalpies for two distinct Li+ diffusion processes were deduced. Ultraslow diffusion corresponding to ionic jump rates down to 0.1 s-1 was observed. It could be confirmed that the static electric field gradients at the two inequivalent Li sites have opposite signs. (author).

1985-01-01

320

Apparatus and method to achieve high-resolution microscopy with non-diffracting or refracting radiation  

Science.gov (United States)

An imaging system employing a coded aperture mask having multiple pinholes is provided. The coded aperture mask is placed at a radiation source to pass the radiation through. The radiation impinges on, and passes through an object, which alters the radiation by absorption and/or scattering. Upon passing through the object, the radiation is detected at a detector plane to form an encoded image, which includes information on the absorption and/or scattering caused by the material and structural attributes of the object. The encoded image is decoded to provide a reconstructed image of the object. Because the coded aperture mask includes multiple pinholes, the radiation intensity is greater than a comparable system employing a single pinhole, thereby enabling a higher resolution. Further, the decoding of the encoded image can be performed to generate multiple images of the object at different distances from the detector plane. Methods and programs for operating the imaging system are also disclosed.

Tobin, Jr., Kenneth W.; Bingham, Philip R.; Hawari, Ayman I.

2012-11-06

 
 
 
 
321

Apparatus and method for OSL-based, remote radiation monitoring and spectrometry  

Science.gov (United States)

Compact, OSL-based devices for long-term, unattended radiation detection and spectroscopy are provided. In addition, a method for extracting spectroscopic information from these devices is taught. The devices can comprise OSL pixels and at least one radiation filter surrounding at least a portion of the OSL pixels. The filter can modulate an incident radiation flux. The devices can further comprise a light source and a detector, both proximally located to the OSL pixels, as well as a power source and a wireless communication device, each operably connected to the light source and the detector. Power consumption of the device ranges from ultra-low to zero. The OSL pixels can retain data regarding incident radiation events as trapped charges. The data can be extracted wirelessly or manually. The method for extracting spectroscopic data comprises optically stimulating the exposed OSL pixels, detecting a readout luminescence, and reconstructing an incident-energy spectrum from the luminescence.

Smith, Leon Eric (Richland, WA); Miller, Steven D. (Richland, WA); Bowyer, Theodore W. (Oakton, VA)

2008-05-20

322

Method and apparatus for detecting explosives  

Science.gov (United States)

A method and apparatus is provided for detecting explosives by thermal imaging. The explosive material is subjected to a high energy wave which can be either a sound wave or an electromagnetic wave which will initiate a chemical reaction in the explosive material which chemical reaction will produce heat. The heat is then sensed by a thermal imaging device which will provide a signal to a computing device which will alert a user of the apparatus to the possibility of an explosive device being present.

Moore, David Steven (Santa Fe, NM)

2011-05-10

323

Control of radiation exposure (principles and methods)  

International Nuclear Information System (INIS)

[en] Biological risks are directly related to the tissue radiation dose, so it is very important to maintain personnel doses as low as realistically possible. This goal can be achieved by minimizing internal contamination and external exposure to radioactive sources

1999-01-01

324

 Methods of detection of selected respiratory viruses  

Directory of Open Access Journals (Sweden)

Full Text Available  Respiratory viruses contribute to significant morbidity and mortality in healthy and immunocompromised individuals and are considered as a significant economic burden in the healthcare system. The similar clinical symptoms in the course of different viral and bacterial respiratory infections make the proper diagnosis difficult. An accurate and prompt diagnostics is crucial for infection control and patient management decisions, especially regarding the use of antibacterial or antiviral therapy and hospitalization. Moreover, the identification of the causative agent eliminates inappropriate use of antibiotics and may reduce the cost of healthcare.A wide variety of diagnostic procedures is applied for the detection of viral agents responsible for respiratory tract infections. For many years, the viral antigen detection and standard isolation technique in cell culture was the main method used in routine diagnostics. However, in recent years the nucleic acid amplification techniques have become widely used and have significantly improved the sensitivity of viral detection in clinical specimens. Molecular diagnostic assays have contributed to revealing high rates of co-infection (multiplex reactions) and allow identification of agents that are difficult to culture.This paper discusses a number of technical aspects of the current most commonly used techniques, their general principles, main benefits and diagnostic value, but also some of their limitations.

Ilona Stefa?ska; Magdalena Romanowska; Lidia B. Brydak

2012-01-01

325

METHOD FOR DETECTING HEMATOPOIETIC STEM CELLS  

UK PubMed Central (United Kingdom)

The present invention provides an isolated nucleic acid sequence encoding KIAA0918, and an isolated nucleic acid sequence that hybridizes under high stringency conditions to a second nucleic acid that is complementary to a nucleic acid sequence encoding KIAA0918. The present invention also discloses a purified KIAA0918 protein, and a purified protein encoded by a nucleic acid sequence that hybridizes under high stringency conditions to a second nucleic acid sequence that is complementary to a nucleic acid sequence encoding KIIAA0918. Also provided is a method of making KIAA0918 protein. The present invention further discloses an antibody specific for KIAA0918, and a method for producing an antibody specific for KIAA0918 protein. Additionally, the present invention is directed to a vector comprising a nucleic acid sequence encoding KIAA0918, and a host cell transformed with a vector comprising a nucleic acid sequence encoding KIAA0918. Also provided is a method for detecting the presence of hematopoietic stem cells in a heterogeneous cell suspension that may contain hematopoietic stem cells, as well as a method for isolating hematopoietic stem cells from a heterogeneous cell suspension that may contain hematopoietic stem cells. Finally, the present invention discloses a method for assessing gene expression in a tissue sample.

BELYAVSKY Alexander; SHMELKOV Sergey; VISSER Jan

326

Electron cascades in sensors for optical detection of ionizing radiation  

Science.gov (United States)

A new class of high-speed detectors, called RadOptic detectors, measures ionizing radiation incident on a transparent semiconductor by sensing changes in the refractive index with an optical probe beam. We describe the role of radiation-initiated electron cascades in setting the sensitivity and the spatial and temporal resolution of RadOptic detectors. We model electron cascades with both analytical and Monte Carlo computational methods. We find that the timescale for the development of an electron cascade is less than of order 100 fs and is not expected to affect the time response of a detector. The characteristic size of the electron cloud is typically less than 2 ?m, enabling high spatial resolution in imaging systems. The electron-hole pair density created by single x-rays is much smaller than the saturation density and, therefore, single events should not saturate the detector.

London, Richard A.; Lowry, Mark E.; Vernon, Stephen P.; Stewart, Richard E.

2013-10-01

327

Detection method and quantitative analysis method for hydrogen radical  

UK PubMed Central (United Kingdom)

The invention is directed to a method of detecting hydrogen radicals present in water or an aqueous solution, characterized in adding sodium salt of 3,5-dibromo-4-nitrosobenzenesulfonic acid (DBNBS) to a sample for detecting the hydrogen radicals by coloring resulting from absorption characteristics thereof, and further characterized in blowing hydrogen gas into a solution of 1,1-diphenyl-2-piclylhydrazyl (DPPH) having absorption in the vicinity of 517 nm and a solution of sodium salt of 3,5-dibromo-4-nitrosobenzenesulfonic acid (DBNBS) at a constant speed in the presence of platinum black for quantitatively analyzing the concentration of the hydrogen radicals from a calibration curve C of a graph of correlation between absorbance in the vicinity of 450 nm derived from a DBNBS azo compound and the concentration of the formed hydrogen radicals.

SHIRAHATA SANETAKA; OTSUBO KAZUMICHI

328

Ferromagnetic Antenna and its Application to Generation and Detection of Gravitational Radiation  

CERN Multimedia

A new type of antenna, which we have called Ferromagnetic Antenna, has been considered for Generation and Detection of Gravitational Radiation. A simple experiment, in which gravitational radiation at 10 GHz can be emitted and received in laboratory, is presented.

De Aquino, F

2002-01-01

329

Method of radiation treatment for fluoropolymer materials  

UK PubMed Central (United Kingdom)

A source of radiation (10,12), particularly a pulsed accelerated electron beam, directs a beam of radiation through an irradiation chamber (14, 50). The irradiation chamber is depleted of oxygen and oxygen containing gases, such as being drawn to a vacuum of 10-1 or greater Torr by a vacuum pump (20, 52). Particulate fluoropolymer material is entrained (36) in substantially oxygen free gas and conveyed through the irradiation chamber. The accelerated electrons break chemical bonds in the fluoropolymer particles and electrostatically charge the particles. Magnetic fields (42, 60) of different polarity rotate the charged particles such that they are irradiated from different sides. The irradiated fluoropolymer particles are cooled (24) and separated (26) from the entraining gas. The entraining gas is recirculated through pneumatic line (34) for a continuous cycle. In an alternate batch processing embodiment, the fluoropolymer material is placed in the shallow container (50) which is sealed and evacuated. The container is conveyed through the pulsed electron beam.

KORENEV SERGEY ALEXANDROVICH; MASEFIELD JOHN; KRIEBEL JERRY

330

An electromagnetic method for cancer detection.  

UK PubMed Central (United Kingdom)

The availability of intraoperative detection techniques to surgeons performingcurative resection of cancer has been shown to improve survival rates and patient outcomes. This work explores a technique for cancer detection with potential for intraoperative use which takes advantage of differences in the electromagnetic (EM) properties between cancerous and healthy tissue. Using time-varying EM fields, electrical eddy currents are generated in tissue samples and other conducting materials, and investigated using phase-sensitive detection. This work is among the first to utilize an EM method involving a phase sensitive scheme for detection of cancer. A prototype EM probe consisting of a pair of coils is designed to detect changes in inductive coupling due to eddy currents when different materials are brought into the probe’s vicinity. Experiments on colon cancer-bearing xenograft mice and human tissue excised during cancer surgeries demonstrate the probe’s consistent ability to differentiate between healthy and cancerous tissue. Experiments on animal tissue show that both the conductivity and the internal structure of the specimen significantly affect the probe’s response. The probe’s response to eddy current configurations that are fixed and well known are studied by performing experiments on individual wire loops, thus forcing the eddy currents to travel in well-defined paths. These experiments, along with an analytical model of the probe’s response, help elucidate the interaction between the probe and biological samples. The analytical model uses an equivalent circuit of the probe interacting with a single wire loop under sinusoidal excitation. The self and mutual inductances of the circuit elements – driver coil, receiver coil, and loop – are calculated numerically from first principles. The numerical calculations are validated against published solutions of relevant problems. Once validated, the circuit element model is compared with experimental data for the wire loops. Good agreement is obtained between the data from the wire loop experiments and the analytical model for sinusoidal driver voltages. The experiments on animal tissue, the supporting experiments on wire loops and the analytical model together provide insight into what governs the probe’s behavior. In particular, both the electrical conductivity and internal structure of the specimen affect the paths of the eddy currents and emerge as critical quantities. This work shows that at the levels of conductivity present in tissue, an increase in ? will lead to an increase in probe sensitivity relative to its null value. It is found that the probe is most sensitive to eddy current domains that are close to the size of the probe itself (i.e. on the order of several millimeters), and in a plane parallel to its face. Measurements on the tissue specimens show that the greatest sensitivity is obtained for sawtooth excitation. A significant conclusion of this work is that information contained in the phase shift of the induced voltage in the receiver coil relative to the voltage across the driver coil is substantially less ambiguous in detecting differences in tissue properties. This approach holds great promise for use in intraoperative detection of cancer, and its selectivity may be further enhanced when used in conjunction with monoclonal antibodies. The method may also be readily extended to imaging of surgically excised tissue and real-time tissue analysis in the operating room.

McFerran J

331

Goals and methods of radiation risk estimation  

International Nuclear Information System (INIS)

The primary goal of general radiation protection rules as they are laid down in the recommendations of the ICRP and have been implemented in radiation protection regulations is to limit the risk incurred by professionally radiation exposed persons. This is the purpose of limit values, which in the case of stochastic risks relate to the effective dose. For reasons of practicability this approach necessitates certain simplifications. For example, tissue weighting factors are determined on the basis of averages across both sexes and all age groups. The ICRP gives nominal risk factors which differentiate only between the general population and the working population. Such simplifications are legitimate provided the conservativity principle is observed. For single-case estimates consideration must also be given to the specific exposure scenario in question as well as to the age at the time of exposure and at the time of diagnosis. Such estimates must always be based on organ dose values and specific age and sex dependent organ-related risks, as well as the uncertainty associated with each input parameter and estimated quantity. The generalised approach (based on values of effective dose) and the more specific approach lead to widely varying results, as is demonstrated by the examples presented in this paper. The paper closes with a discussion of the risks associated with X-ray diagnostics. Here too, though widespread, the use of the effective dose is inappropriate. Recent analyses have shown that this results in distorted risk estimates.

2005-01-01

332

Detecting a non-Gaussian stochastic background of gravitational radiation  

CERN Multimedia

We derive a detection method for a stochastic background of gravitational waves produced by events where the ratio of the average time between events to the average duration of an event is large. Such a signal would sound something like popcorn popping. Our derivation is based on the somewhat unrealistic assumption that the duration of an event is smaller than the detector time resolution.

Drasco, S; Drasco, Steve; Flanagan, Eanna E.

2002-01-01

333

Thermoluminescence method for detection of irradiated food  

International Nuclear Information System (INIS)

A method of thermoluminescence (TL) analysis was developed for the detection of irradiated foods. The TL method is based on the determination of thermoluminescence of adhering or contaminating minerals separated from foods by wet sieving and treatment with high density liquid. Carbon tetrachloride provided a suitable alternative for foods that form gels with water. Thermoluminescence response of minerals in a first TL measurement is normalised with a second TL measurement of the same mineral sample after calibration irradiation to a dose of 5 kGy. The decision about irradiation is made on the basis of a comparison of the two TL spectra: if the two TL glow curves match in shape and intensity the sample has been irradiated, and if they are clearly different it has not been irradiated. An attractive feature of TL analysis is that the mineral material itself is used for calibration; no reference material is required. Foods of interest in the investigation were herbs, spices, berries and seafood. The presence of minerals in samples is a criterion for application of the method, and appropriate minerals were found in all herbs, spices and berries. The most common minerals in terrestrial food were tecto-silicates - quartz and feldspars - which with their intense and stable thermoluminescence were well suited for the analysis. Mica proved to be useless for detection purposes, whereas carbonate in the form of calcite separated from intestines of seafood was acceptable. Fading of the TL signal is considerable in the low temperature part of the glow curve during a storage of several months after irradiation. However, spices and herbs could easily be identified as irradiated even after two years storage. Conditions for seafood, which is stored in a freezer, are different, and only slight fading was observed after one year. The effect of mineral composition and structure on TL was studied for feldspars. Feldspars originating from subtropical and tropical regions exhibit lower TL intensity than feldspars from cold regions, evidently because a more altered mineral structure is typical in warm water regions. A new autoradiographic method to determine luminescence of irradiated rock surfaces was developed for the study. The method of thermoluminescence analysis has been used for the official control analysis of irradiated food in Finland since 1990. In the course of the study, about 500 analyses were carried out for the Finnish Customs Laboratory. Eighty lots of irradiated herbs or spices and 10 lots of irradiated seafood were found. During the last two years, irradiated green tea in spice mixtures and irradiated frog legs have been detected. No irradiated berry or mushroom products have been found. Screening with a photostimulated luminescence (PSL) instrument, followed by TL analysis to confirm the positive and ambiguous samples, provides a reliable tool for the identification of irradiated food containing adhering or contaminating minerals. The reliability of the TL method was proved in European trials. Standardisation of the method has been undertaken by the European Committee for Standardization (CEN). A TL method based on the determination of TL silicate minerals in dry herbs and spices has recently been accepted as an official CEN standard. (orig.)

1998-01-01

334

Method and apparatus for sequentially combining pulsed beams of radiation  

International Nuclear Information System (INIS)

Method and apparatus are presented for combining a sequence of radiation pulses in plural beams to provide a common axis output beam of increased repetition rate. An optical correction system is employed to compensate for dynamic angular motion of the output radiation beam over the duration of each pulse. (Auth.)

1974-01-30

335

Methodical recommendations for power unit comprehensive engineering and radiation survey  

International Nuclear Information System (INIS)

The article describes power unit radiation survey methods developed and applied during conduction of Ch NPP unit I Comprehensive Engineering Radiation Survey. Special requirements for units under decommissioning, main survey principals, criteria for definition of volume and the order of survey for various systems of a NPP Unit are included.

2000-01-01

336

Radiation detection from phase-locked serial dc SQUID arrays  

DEFF Research Database (Denmark)

We report on synchronous operation of series arrays of inductively coupled superconducting quantum interference devices (SQUIDs). Each array consisted of N=3 or 11 dc SQUIDs with common inductances providing a strong interaction between neighboring cells. Externally shunted (betac[approximately-equal-to]1) trilayer Nb—AlOx—Nb Josephson junctions were used. Coherent radiation was detected in the frequency range f=67–73 GHz while the array voltage was VN=NfPhi0 (Phi0=2.07×10?15 V s). The stability of the coherent state was influenced by the external dc magnetic field. The linewidth depended on the external loading. For small loading it was N times smaller than expected for a single cell. The influence of the inductive coupling mechanism on the operation of discrete Josephson junction circuits and the similarity to the coupling in layered structures of long Josephson junctions is discussed. Journal of Applied Physics is copyrighted by The American Institute of Physics.

Kaplunenko, V. K.; Mygind, Jesper

1993-01-01

337

Detection of orphan radioactive sources during radiation monitoring  

International Nuclear Information System (INIS)

Many radioactive sources are reported as lost every year from different parts of the world due to lack of administrative control or due to theft. Massive search operations carried out led to the discovery of some, few caused radiological emergencies in public domain and many are yet to be traced. Prevention of these orphan sources from causing inadvertent exposure of public can be achieved by timely search and detection operation for these sources. Systems and methodologies for search of orphan sources are developed as a part of BARC Emergency Response Centre's activities and are tested in many aerial and field radiation monitoring exercises. In this paper, results of an estimation carried out to assist the search and locating of orphan sources is presented. Dose rates have been compared at various monitoring locations of three inadequately shielded sources (137Cs, 60Co, 192Ir) of strength 3.7 TBq (100 Ci) each left inside a room of 30cm thick concrete wall. (author)

2008-01-01

338

UTILIZATION OF PHOSWICH DETECTORS FOR SIMULTANEOUS, MULTIPLE RADIATION DETECTION  

International Nuclear Information System (INIS)

[en] A phoswich radiation detector is comprised of a phosphor sandwich in which several different phosphors are viewed by a common photomultiplier. By selecting the appropriate phosphors, this system can be used to simultaneously measure multiple radiation types (alpha, beta, gamma and/or neutron) with a single detector. Differentiation between the signals from the different phosphors is accomplished using digital pulse shape discrimination techniques. This method has been shown to result in accurate discrimination with highly reliable and versatile digital systems. This system also requires minimal component count (i.e. only the detector and a computer for signal processing). A variety of detectors of this type have been built and tested including: (1) a triple phoswich system for alpha/beta/gamma swipe counting, (2) two well-type detectors for measuring low levels of low energy photons in the presence of a high energy background, (3) a large area detector for measuring beta contamination in the presence of a photon background, (4) another large area detector for measuring low energy photons from radioactive elements such as uranium in the presence of a photon background. An annular geometry, triple phoswich system optimized for measuring alpha/beta/gamma radiation in liquid waste processing streams is currently being designed

2003-01-01

339

Fiber-optic radiation sensor for detection of tritium  

Science.gov (United States)

The objective of this study is to develop the radiation sensor, which is composed of a scintillator, an optical fiber bundle and a light measuring device to detect the tritium in real-time. In this study, we have fabricated fiber-optic radiation sensors using inorganic scintillators and plastic optical fiber bundles. Each scintillator interacts with electron or beta ray and generates 455–550 nm wavelength of scintillation photons. An optical fiber bundle is usually made of plastic or glass, which is used to guide the light signal from a scintillating probe to light measuring device. For the purpose of selecting the best scintillator with a high efficiency, fiber-optic sensors manufactured using three kinds of inorganic scintillator such as Gd2O2S:Tb, Y3Al5O12:Ce and CsI:Tl, and they are tested with a metal hydride type of tritium source. In addition, the scintillation photons are measured as a function of distance between a fiber-optic sensor and source. Finally, we have measured the amounts of scintillation photon with different activities of tritium source and compared the measured results with those obtained using a surface activity monitor.

Jang, K. W.; Cho, D. H.; Yoo, W. J.; Seo, J. K.; Heo, J. Y.; Park, J.-Y.; Lee, B.

2011-10-01

340

Direct tomography of the 900 scattered radiation by gamma camera detection. Performance and application to the lungs  

International Nuclear Information System (INIS)

The characteristics and performance are described of a simple direct morphological tomography method (i.e. non computerized), which has been studied, made and applied in lung diagnosis. This method is based on the principle of the gamma camera detection of the 900 scattered radiation

1978-06-09

 
 
 
 
341

Method of detecting microorganisms within a specimen  

UK PubMed Central (United Kingdom)

The present invention relates to a method of preparing reactants intended for a test for detecting microorganisms and especially for detecting infections in humans or animals, characterized in that it comprises the following steps: a) centrifugation of a biological or artificial liquid medium containing a selected specific microorganism b) filtration of the supernatant obtained in step a) c) preparation of a series of diluted specimens corresponding to increasing dilutions of the filtrate obtained in step b) until the filtrate has been diluted by a factor of at least 10 d) subjection of the diluted specimens obtained in step c) to an electric, magnetic and/or electromagnetic excitation field e) analysis of the electrical signals detected by means of a solenoid and digital recording of said electrical signal after analogue/digital conversion of said signal f) selection of the diluted specimens with which characteristic electrical signals are obtained in e), i.e. signals having an amplitude at least 1.5 times greater than the background noise signals emitted by the water and/or having a frequency shift towards higher values g) introduction of the diluted specimens selected at step f) into protective enclosures, which protect said dilutions from the external electromagnetic fields h) distribution of one of said diluted specimens of step g) volume to volume in two tubes, one, T1, remaining in the protective enclosure protecting said diluted specimens from interference by the external electromagnetic fields, which tube will serve as reference solution, and the other, T2, also being placed in a protective enclosure, which tube will be subsequently subjected to the presence of or be in contact with a specimen suspected to contain said selected specific microorganism.

LUC MONTAGNIER; JAMAL AISSA

342

Odour Detection Methods: Olfactometry and Chemical Sensors  

Directory of Open Access Journals (Sweden)

Full Text Available The complexity of the odours issue arises from the sensory nature of smell. From the evolutionary point of view olfaction is one of the oldest senses, allowing for seeking food, recognizing danger or communication: human olfaction is a protective sense as it allows the detection of potential illnesses or infections by taking into account the odour pleasantness/unpleasantness. Odours are mixtures of light and small molecules that, coming in contact with various human sensory systems, also at very low concentrations in the inhaled air, are able to stimulate an anatomical response: the experienced perception is the odour. Odour assessment is a key point in some industrial production processes (i.e., food, beverages, etc.) and it is acquiring steady importance in unusual technological fields (i.e., indoor air quality); this issue mainly concerns the environmental impact of various industrial activities (i.e., tanneries, refineries, slaughterhouses, distilleries, civil and industrial wastewater treatment plants, landfills and composting plants) as sources of olfactory nuisances, the top air pollution complaint. Although the human olfactory system is still regarded as the most important and effective “analytical instrument” for odour evaluation, the demand for more objective analytical methods, along with the discovery of materials with chemo-electronic properties, has boosted the development of sensor-based machine olfaction potentially imitating the biological system. This review examines the state of the art of both human and instrumental sensing currently used for the detection of odours. The olfactometric techniques employing a panel of trained experts are discussed and the strong and weak points of odour assessment through human detection are highlighted. The main features and the working principles of modern electronic noses (E-Noses) are then described, focusing on their better performances for environmental analysis. Odour emission monitoring carried out through both the techniques is finally reviewed in order to show the complementary responses of human and instrumental sensing.

Magda Brattoli; Gianluigi de Gennaro; Valentina de Pinto; Annamaria Demarinis Loiotile; Sara Lovascio; Michele Penza

2011-01-01

343

Evaluation method for radiative heat transfer in polydisperse water droplets  

Energy Technology Data Exchange (ETDEWEB)

Simplifications of the model for nongray radiative heat transfer analysis in participating media comprised of polydisperse water droplets are presented. Databases of the radiative properties for a water droplet over a wide range of wavelengths and diameters are constructed using rigorous Mie theory. The accuracy of the radiative properties obtained from the database interpolation is validated by comparing them with those obtained from the Mie calculations. The radiative properties of polydisperse water droplets are compared with those of monodisperse water droplets with equivalent mean diameters. Nongray radiative heat transfer in the anisotropic scattering fog layer, including direct and diffuse solar irradiations and infrared sky flux, is analyzed using REM{sup 2}. The radiative heat fluxes within the fog layer containing polydisperse water droplets are compared with those in the layer containing monodisperse water droplets. Through numerical simulation of the radiative heat transfer, polydisperse water droplets can be approximated by using the Sauter diameter, a technique that can be useful in several research fields, such as engineering and atmospheric science. Although this approximation is valid in the case of pure radiative transfer problems, the Sauter diameter is reconfirmed to be the appropriate diameter for approximating problems in radiative heat transfer, although volume-length mean diameter shows better accordance in some cases. The CPU time for nongray radiative heat transfer analysis with a fog model is evaluated. It is proved that the CPU time is decreased by using the databases and the approximation method for polydisperse particulate media.

Maruyama, Shigenao [Institute of Fluid Science, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai 980-8577 (Japan)], E-mail: maruyama@ifs.tohoku.ac.jp; Nakai, Hirotaka [School of Engineering, Tohoku University, 6-6, Aoba, Aramaki-aza, Aoba-ku, Sendai 980-8579 (Japan)], E-mail: hirotaka@pixy.ifs.tohoku.ac.jp; Sakurai, Atsushi [School of Engineering, Tohoku University, 6-6, Aoba, Aramaki-aza, Aoba-ku, Sendai 980-8579 (Japan); Komiya, Atsuki [Institute of Fluid Science, Tohoku University, 2-1-1, Katahira, Aoba-ku, Sendai 980-8577 (Japan)

2008-01-15

344

Atoms, radiation, and radiation protection  

Energy Technology Data Exchange (ETDEWEB)

This book describes basic atomic and nuclear structure, the physical processes that result in the emission of ionizing radiations, and external and internal radiation protection criteria, standards, and practices from the standpoint of their underlying physical and biological basis. The sources and properties of ionizing radiation-charged particles, photons, and neutrons-and their interactions with matter are discussed in detail. The underlying physical principles of radiation detection and systems for radiation dosimetry are presented. Topics considered include atomic physics and radiation; atomic structure and radiation; the nucleus and nuclear radiation; interaction of heavy charged particles with matter; interaction of beta particles with matter; phenomena associated with charged-particle tracks; interaction of photons with matter; neutrons, fission and criticality; methods of radiation detection; radiation dosimetry; chemical and biological effects of radiation; radiation protection criteria and standards; external radiation protection; and internal dosimetry and radiation protection.

Turner, J.E.

1986-01-01

345

The detection of the X ray blow off impulses under the condition of intense nuclear radiation and its anti-radiation electronic studies  

International Nuclear Information System (INIS)

The detecting studies of the blow off impulses produced in the flat targets irradiated by nuclear explosion X ray are discussed. In detections, the detector principle of directly measuring the specific series of time intervals and variable reluctance transducing technique were used. A set of effective methods of anti-radiative interference are adopted in the whole detecting system. In addition, the moving frictions of the target groups are calibrated on the equipment of powder gun. Finally, the comparisons between the detective data and the computed results about the X ray blow off impulses are given. The results indicate that they coincide with each other satisfactorily

1999-01-01

346

METHOD OF ELECTROCHEMICAL DETECTION OF IMMUNOACTIVE MACROMOLECULES  

UK PubMed Central (United Kingdom)

A method of electrochemical detection of immunoactive macromolecules in test solutions, which involves producing an immunosensor comprising a specific-receptor-modified membrane; forming an electrochemical measuring cell from the immuno-sensitive sensor and a reference electrode linked by a measuring instrument; placing the latter into the working solution, and determining the displacement of the isoelectric point of the membrane in relation to the concentration of macromolecules in the solution under test, by measuring the cell potential with step-changes in the ionic strength of the working solution, in which the membrane is formed from electroconductive polymer by electrochemical synthesis from a monomer solution containing specific receptors on the surface of the potentiometric electrode; to determine the isoelectric point displacement of the membrane, a test solution with an ionic strength greater than that of the working solution at constant pH is added to the working solution.

FARMAKOVSKI Dmitri Alexandrovich; MILANOVSKI Yevgeni Yurevich; CHERKASOV Vladimir Rurikovich; BIRYUKOV Yuri Sergeyevich; KOMAROV Boris Vladimirovich

347

Molecular methods of virus detection in lymphoma.  

UK PubMed Central (United Kingdom)

The herpesviruses Epstein-Barr virus (EBV) and human herpesvirus 8 and the retrovirus human T-cell leukemia virus type 1 are directly implicated in the pathogenesis of lymphoma and leukemia in man. EBV is associated with an expanding spectrum of lymphomas and it would appear likely that additional, possibly novel, viruses will be implicated in lymphoma pathogenesis in the future. This chapter describes techniques that may be useful in the analysis of viruses and lymphoma including a standard EBV EBER in situ hybridization assay and a degenerate PCR assay for detection of novel herpesviruses. Lastly, a method for analysis of next-generation sequences in the quest for novel viruses is described.

Jarrett RF; Gallagher A; Gatherer D

2013-01-01

348

Hydraulic control unit detection method and device  

International Nuclear Information System (INIS)

The present invention provides detection method and device for ensuring integrity of hydraulic control units of a BWR type power plant and shortening the term for plant periodical inspection. Namely, (1) the integrity of the hydraulic control units is confirmed based on the time required from the input of control rod driving signals to the hydraulic control units to the completion of the control rod operation, (2) the integrity of the hydraulic control units is confirmed based on the driving time per 1 notch of the notches formed on control rods, (3) the above-mentioned integrity is judged by setting the range of the time assumed as integral based on integral data previously measured and determining whether the above-mentioned time is within the predetermined range or not, (4) this operation is conducted during a periodical inspection, and inspection is conducted by disassembling only the hydraulic control unit which is judged to be not integral. (I.S.)

1996-10-22

349

Material degradation detection by magnetic method  

Energy Technology Data Exchange (ETDEWEB)

To be able to evaluate the life of nuclear power plant becomes inevitable as the plant operating period extends. So, magnetic methods using Barkhausen noise (BHN) and B-H curve were applied to detect the degradation by fatigue and thermal aging. Low alloy steel (SA 508 cl.2) was fatigued, and duplex stainless steel (SCS 14A) was aged at 400 C. For the degradation by thermal aging, BHN and B-H curve were measured and good correlations between magnetic properties and aging time were obtained. For fatigue, BHN was measured at predetermined loading cycles and, at each predetermined cycle, the effect of stress or strain condition in the measurement was evaluated. The results showed that BHN was affected by the stress or strain condition in the measurement, the cause of which seemed to be the change of internal stress condition, and by identifying the measuring condition, good correlation between BHN and fatigue damage was obtained.

Yamaguchi, A.; Maeda, N.; Sugibayashi, T. [Japan Power Engineering and Inspection Corp., Yokohama (Japan)

1995-08-01

350

Hydraulic control unit detection method and device  

Energy Technology Data Exchange (ETDEWEB)

The present invention provides detection method and device for ensuring integrity of hydraulic control units of a BWR type power plant and shortening the term for plant periodical inspection. Namely, (1) the integrity of the hydraulic control units is confirmed based on the time required from the input of control rod driving signals to the hydraulic control units to the completion of the control rod operation, (2) the integrity of the hydraulic control units is confirmed based on the driving time per 1 notch of the notches formed on control rods, (3) the above-mentioned integrity is judged by setting the range of the time assumed as integral based on integral data previously measured and determining whether the above-mentioned time is within the predetermined range or not, (4) this operation is conducted during a periodical inspection, and inspection is conducted by disassembling only the hydraulic control unit which is judged to be not integral. (I.S.)

Matsui, Yuji; Shigenaka, Naoto; Senoo, Makoto; Takahashi, Fuminobu

1998-05-15

351

Development of nondestructive evaluation method on radiation damage using micromagnetic methods  

International Nuclear Information System (INIS)

The nuclear reactor pressure vessel is degraded by the high energy neutron bombardments during operation periods. Life extension of existing nuclear power plants requires the development of innovative NDE techniques for inspection of aged components. The magnetic method has been recently demonstrated as a promising technique. One major difficulty in using these particular techniques is to correlate the changes in the measured NDT signals with the microstructural changes occurred in the material due to aging. This problem may be solved through careful microstructural examinations of materials damage and introduction of signal analysis techniques. The NDE and science research center (NDE and S-RC) established in the Iwate University is studying about the application of minor loop method to the radiation damage. The minor loop technique in the detection of radiation damage is complement method of Barkhausen noise which developed in the Korea Atomic Energy Research Institute (KAERI). The cooperation between NDE and S-RC and KAERI are very important in the development of magnetic NDE techniques. The aim of this joint project will be the investigation of the magnetic properties for commen specimens using original methods, establishment of the fundamentals of magnetic NDE technique, and ensuring a safe operation of nuclear power plants

2007-01-01

352

Comparison of methods for determining the second-order detection efficiency of a VUV spectrometer.  

UK PubMed Central (United Kingdom)

Four independent procedures were developed and tested to measure the apparatus response function of a VUV spectrometer-detector system for unpolarized 46-nm radiation dispersed in second order. These measurements were made to allow the use of continuum synchrotron radiation for the calibration of the response of the spectrometer-detector system for dispersion of 92-nm radiation in first order with full correction for the effects of synchrotron radiation dispersed in second order. In the first method, synchrotron radiation was used in combination with a thin Al foil to block out synchrotron radiation at 92 nm while allowing 46-nm radiation to enter the spectrometer. In the second as well as the third method NeII 46-nm line radiation was used to measure the response function in first and second order. The line radiation was produced by (1) an electron beam exciting a Ne gas target for which the resulting VUV light illuminated the entire grating and (2) a duoplasmatron VUV light source operating with Ne gas producing a small spot of radiation that was scanned across the surface of the spectrometer grating. In the fourth method the difference in the spectral distributions of synchrotron radiation produced by electrons with different kinetic energies was employed to deduce the second-order detection efficiency. The ratio of the second- to firstorder response function for 46-nm radiation could be determined to a precision of 6% using the bandpass filter and electron-beam methods, 10% using the duoplasmatron method, and 250% using the multiple electron energy method.

Kendrick RL; McPherson A; Rouze N; Westerveld WB; Risley JS

1987-05-01

353

Comparison of methods for determining the second-order detection efficiency of a VUV spectrometer  

Science.gov (United States)

Four independent procedures were developed and tested to measure the apparatus response function of a VUV spectrometer-detector system for unpolarized 46-nm radiation dispersed in second order. These measurements were made to allow the use of continuum synchrotron radiation for the calibration of the response of the spectrometer-detector system for dispersion of 92-nm radiation in first order with full correction for the effects of synchrotron radiation dispersed in second order. In the first method, synchrotron radiation was used in combination with a thin Al foil to block out synchrotron radiation at 92 nm while allowing 46-nm radiation to enter the spectrometer. In the second as well as the third method, Ne II 46-nm line radiation was used to measure the response function in first and second order. The line radiation was produced by: (1) an electron beam exciting a Ne gas target for which the resulting VUV light illuminated the entire grating; and (2) a duoplasmatron VUV light source operating with Ne gas producing a small spot of radiation that was scanned across the surface of the spectrometer grating. In the fourth method the difference in the spectral distributions of synchrotron radiation produced by electrons with different kinetic energies was employed to deduce the second-order detection efficiency. The ratio of the second-order to first-order response function for 56-nm radiation could be determined to a precision of 6 percent using the bandpass filter and electron-beam methods, 10 percent using the duoplasmatron method, and 250 percent using the multiple electron energy method.

Kendrick, Richard L.; McPherson, Armon; Rouze, N.; Westerveld, W. B.; Risley, John S.

1987-05-01

354

Apparatus and method to compensate for refraction of radiation  

Energy Technology Data Exchange (ETDEWEB)

An apparatus to compensate for refraction of radiation passing through a curved wall of an article is provided. The apparatus of a preferred embodiment is particularly advantageous for use in arc tube discharge diagnostics. The apparatus of the preferred embodiment includes means for pre-refracting radiation on a predetermined path by an amount equal and inverse to refraction which occurs when radiation passes through a first wall of the arc tube such that, when the radiation passes through the first wall of the arc tube and into the cavity thereof, the radiation passes through the cavity approximately on the predetermined path; means for releasably holding the article such that the radiation passes through the cavity thereof; and means for post-refracting radiation emerging from a point of the arc tube opposite its point of entry by an amount equal and inverse to refraction which occurs when radiation emerges from the arc tube. In one embodiment the means for pre-refracting radiation includes a first half tube comprising a longitudinally bisected tube obtained from a tube which is approximately identical to the arc tube's cylindrical portion and a first cylindrical lens, the first half tube being mounted with its concave side facing the radiation source and the first cylindrical lens being mounted between the first half tube and the arc tube and the means for post-refracting radiation includes a second half tube comprising a longitudinally bisected tube obtained from a tube which is approximately identical to the arc tube's cylindrical portion and a second cylindrical lens, the second half tube being mounted with its convex side facing the radiation source and the second cylindrical lens being mounted between the arc tube and the second half tube. Methods to compensate for refraction of radiation passing into and out of an arc tube is also provided.

Allen, Gary R. (Georgetown, MA); Moskowitz, Philip E. (Peabody, MA)

1990-01-01

355

Method for evaluation of radiative properties of glass samples  

Energy Technology Data Exchange (ETDEWEB)

The paper presents a simple calculation method which serves for an evaluation of radiative properties of window glasses. The method is based on a computer simulation model of the energy balance of a thermally insulated box with selected glass samples. A temperature profile of the air inside of the box with a glass sample exposed to affecting radiation was determined for defined boundary conditions. The spectral range of the radiation was considered in the interval between 280 and 2500 nm. This interval is adequate to the spectral range of solar radiation affecting windows in building facades. The air temperature rise within the box was determined in a response to the affecting radiation in the time between the beginning of the radiation exposition and the time of steady-state thermal conditions. The steady state temperature inside of the insulated box serves for the evaluation of the box energy balance and determination of the glass sample radiative properties. These properties are represented by glass characteristics as mean values of transmittance, reflectance and absorptance calculated for a defined spectral range. The data of the computer simulations were compared to experimental measurements on a real model of the insulated box. Results of both the calculations and measurements are in a good compliance. The method is recommended for preliminary evaluation of window glass radiative properties which serve as data for energy evaluation of buildings.

Mohelnikova, Jitka [Faculty of Civil Engineering, Brno University of Technology, Veveri 95, 602 00 Brno (Czech Republic)], E-mail: mohelnikova.j@fce.vutbr.cz

2008-04-15

356

A method for calculation of radiation quantities at all points in gamma radiation calibration fields  

International Nuclear Information System (INIS)

Radiation quantity values at all points of a known distance range of gamma radiation calibration fields were calculated using a mathematical method. The method is based on interpolation using Chi-square test on a set of experimental data at optional points of both collimated and un-collimated calibration set-ups by means of a reference instrument. In comparison with Monte Carlo calculations, the values that were calculated by this method differ by

2008-01-01

357

Radiation sterilization as compared with another methods of making sterile  

International Nuclear Information System (INIS)

Presentation is devoted to sterilization and hygienization of food, medicinal articles and cosmetics. Radiosterilization is compared with other methods. Advantages of fast electron- and gamma radiation sterilization are stressed.

2007-01-01

358

Radiation resistance of biological reagents for in situ life detection.  

Science.gov (United States)

Life on Mars, if it exists, may share a common ancestry with life on Earth derived from meteoritic transfer of microbes between the planets. One means to test this hypothesis is to isolate, detect, and sequence nucleic acids in situ on Mars, then search for similarities to known common features of life on Earth. Such an instrument would require biological and chemical components, such as polymerase and fluorescent dye molecules. We show that reagents necessary for detection and sequencing of DNA survive several analogues of the radiation expected during a 2-year mission to Mars, including proton (H-1), heavy ion (Fe-56, O-18), and neutron bombardment. Some reagents have reduced performance or fail at higher doses. Overall, our findings suggest it is feasible to utilize space instruments with biological components, particularly for mission durations of up to several years in environments without large accumulations of charged particles, such as the surface of Mars, and have implications for the meteoritic transfer of microbes between planets. PMID:23330963

Carr, Christopher E; Rowedder, Holli; Vafadari, Cyrus; Lui, Clarissa S; Cascio, Ethan; Zuber, Maria T; Ruvkun, Gary

2013-01-01

359

Radiation resistance of biological reagents for in situ life detection.  

UK PubMed Central (United Kingdom)

Life on Mars, if it exists, may share a common ancestry with life on Earth derived from meteoritic transfer of microbes between the planets. One means to test this hypothesis is to isolate, detect, and sequence nucleic acids in situ on Mars, then search for similarities to known common features of life on Earth. Such an instrument would require biological and chemical components, such as polymerase and fluorescent dye molecules. We show that reagents necessary for detection and sequencing of DNA survive several analogues of the radiation expected during a 2-year mission to Mars, including proton (H-1), heavy ion (Fe-56, O-18), and neutron bombardment. Some reagents have reduced performance or fail at higher doses. Overall, our findings suggest it is feasible to utilize space instruments with biological components, particularly for mission durations of up to several years in environments without large accumulations of charged particles, such as the surface of Mars, and have implications for the meteoritic transfer of microbes between planets.

Carr CE; Rowedder H; Vafadari C; Lui CS; Cascio E; Zuber MT; Ruvkun G

2013-01-01

360

Screening for early detection of radiation-associated thyroid cancer  

International Nuclear Information System (INIS)

In the 1950s, approximately 20,000 Israeli children received scalp irradiation as treatment for tinea capitis (ringworm of the scalp). To evaluate the necessity and feasibility of early screening of these individuals for thyroid cancer, a small pilot program was undertaken. The examination consisted of a thorough palpation of the thyroid gland and the surrounding area. A sup(99m)Tc thyroid scan and thyroid function tests were performed on individuals in whom palpation suggested a nodular abnormality. A multidisciplinary committee then made a recommendation for or against surgery. A total of 443 persons were screened, and nodular abnormalities of the thyroid were detected in 24 (5.4%). Of these persons, nine displayed symptomatology or reported knowledge of a thyroid condition; despite this, three of them were not receiving treatment. This left 18 subjects - 15 new cases and 3 previously untreated patients - needing follow-up care. Altogether nine persons were recommended for surgery, but one refused. All eight of the excised lesions were benign: four colloid nodules and four adenomas. While the screening program was feasible, the fact that no cancers were detected suggested that in a population exposed to a very low dose of radiation, thyroid screening may not be justified on a large scale..

1984-01-01

 
 
 
 
361

Method of radiation degradation of PTFE under vacuum conditions  

International Nuclear Information System (INIS)

A new method of radiation degradation of Polytetrafluoroethylene (PTFE) under vacuum conditions is considered in this report. The combination of glow gas discharge and electrical surface discharge (on surface and inside PTFE) increases the efficiency of thermal-radiation degradation. The main mechanism of this degradation method consists of the breaking of C-C and C-F bonds. The vacuum conditions allow decreasing of the concentration of toxic compounds, such as a HF. Experimental results for degradation of PTFE are presented.

2004-01-01

362

Method of radiation degradation of PTFE under vacuum conditions  

Energy Technology Data Exchange (ETDEWEB)

A new method of radiation degradation of Polytetrafluoroethylene (PTFE) under vacuum conditions is considered in this report. The combination of glow gas discharge and electrical surface discharge (on surface and inside PTFE) increases the efficiency of thermal-radiation degradation. The main mechanism of this degradation method consists of the breaking of C-C and C-F bonds. The vacuum conditions allow decreasing of the concentration of toxic compounds, such as a HF. Experimental results for degradation of PTFE are presented.

Korenev, Sergey E-mail: sergey_korenev@steris.com

2004-10-01

363

Method of radiation degradation of PTFE under vacuum conditions  

Science.gov (United States)

A new method of radiation degradation of Polytetrafluoroethylene (PTFE) under vacuum conditions is considered in this report. The combination of glow gas discharge and electrical surface discharge (on surface and inside PTFE) increases the efficiency of thermal-radiation degradation. The main mechanism of this degradation method consists of the breaking of C-C and C-F bonds. The vacuum conditions allow decreasing of the concentration of toxic compounds, such as a HF. Experimental results for degradation of PTFE are presented.

Korenev, Sergey

2004-09-01

364

Two different hematocrit detection methods: Different methods, different results?  

Directory of Open Access Journals (Sweden)

Full Text Available Abstract Background Less is known about the influence of hematocrit detection methodology on transfusion triggers. Therefore, the aim of the present study was to compare two different hematocrit-assessing methods. In a total of 50 critically ill patients hematocrit was analyzed using (1) blood gas analyzer (ABLflex 800) and (2) the central laboratory method (ADVIA® 2120) and compared. Findings Bland-Altman analysis for repeated measurements showed a good correlation with a bias of +1.39% and 2 SD of ± 3.12%. The 24%-hematocrit-group showed a correlation of r2 = 0.87. With a kappa of 0.56, 22.7% of the cases would have been transfused differently. In the-28%-hematocrit group with a similar correlation (r2 = 0.8) and a kappa of 0.58, 21% of the cases would have been transfused differently. Conclusions Despite a good agreement between the two methods used to determine hematocrit in clinical routine, the calculated difference of 1.4% might substantially influence transfusion triggers depending on the employed method.

Bosshart Marco; Stover John F; Stocker Reto; Asmis Lars M; Feige Jörg; Neff Thomas A; Schuepbach Reto A; Cottini Silvia R; Béchir Markus

2010-01-01

365

An optimal method in power plant boiler leak detection  

International Nuclear Information System (INIS)

[en] In recent decades many theoretical and experimental projects have been done in leak detection of boiler tubes. In this paper, exciting applied methods for leak detection in boiler environment conditions is outlined. A cumulative review on acoustic and mass balancing methods is presented and several methods are introduced, compared and discussed. The best method for leak detection in hot and high-pressure boiler tubes as the acoustic air borne leak detection method is suggested and analyzed

2004-01-01

366

Radiative Transfer in Star Formation: Testing FLD and Hybrid Methods  

CERN Multimedia

We perform a comparison between two radiative transfer algorithms commonly employed in hydrodynamical calculations of star formation: grey flux limited diffusion and the hybrid scheme, in addition we compare these algorithms to results from the Monte-Carlo radiative transfer code MOCASSIN. In disc like density structures the hybrid scheme performs significantly better than the FLD method in the optically thin regions, with comparable results in optically thick regions. In the case of a forming high mass star we find the FLD method significantly underestimates the radiation pressure by a factor of ~100.

Owen, James E; Clarke, Cathie J

2012-01-01

367

Fluorescence in situ hybridisation in chromosome aberration detection in subjects occupationally exposed to ionising radiation  

International Nuclear Information System (INIS)

[en] For more than two decades, chromosomal aberration analysis has been used to detect structural chromosomal aberrations as sensitive biodosimeters of occupational exposure to ionising radiation. Its use is also recommended by the World Health Organisation. Changes in chromosome structure detected by that method are considered to be early biomarkers of a possible malignant disease. Aberrations detected by the method are unstable and can be found in the lymphocytes of irradiated personnel only within a limited time after exposure. To detect stable chromosomal aberrations, which persist after exposure, multicolour fluorescent in situ hybridisation has to be used. Using DNA probes labelled with different fluorochromes, it dyes each pair of chromosomes with different colour. Due to the dynamic of unstable aberration formation, chromosomal aberration analysis is more suitable in genome damage assessment of recent exposures. On the other hand, fluorescence in situ hybridisation gives the information on chromosome instability caused by long-term occupational exposure to ionising radiation. Considering the high costs of fluorescence in situ hybridisation and the uncertainty of the result, it should be used in biodosimetry only when it is absolutely necessary.(author)

2005-01-01

368

A method for radiation grafting of polyolefins  

International Nuclear Information System (INIS)

The procedure of radiation grafting of polyolefins in the swelled state with graft monomers from the class of methacrylic and acrylic acids and their reactive derivatives, was modified so as to obtain copolymers with ample short (often single-membered) side chains of the acids. To achieve this, the grafting was conducted in the presence of efficient radical polymerization inhibitors from the class of polyvalent phenols such as hydroquinone or tert-butylpyrocatechol, and of efficient chain carriers from the class of halogenated aliphatic hydrocarbons and mercapto compounds such as CCl4, CHCl3, CHBr3, thioacetic acid or ethyl bromide. The polymers so obtained are well suited to the manufacture of dialysis and electrodialysis membranes and hollow fibres. (P.A.).

1986-04-05

369

Nuclear analysis methods. Rudiments of radiation protection; Methodes nucleaires d`analyse. Notions de radioprotection  

Energy Technology Data Exchange (ETDEWEB)

The nuclear analysis methods are generally used to analyse radioactive elements but they can be used also for chemical analysis, with fields such analysis and characterization of traces. The principles of radiation protection are explained (ALARA), the biological effects of ionizing radiations are given, elements and units used in radiation protection are reminded in tables. A part of this article is devoted to how to use radiation protection in a nuclear analysis laboratory. (N.C.)

Roth, E. [Conservatoire National des Arts et Metiers (CNAM), 75 - Paris (France)

1998-06-01

370

An inverse method for radiation transport  

Energy Technology Data Exchange (ETDEWEB)

Adjoint functions have been used with forward functions to compute gradients in implicit (iterative) solution methods for inverse problems in optical tomography, geoscience, thermal science, and other fields, but only once has this approach been used for inverse solutions to the Boltzmann transport equation. In this paper, this approach is used to develop an inverse method that requires only angle-independent flux measurements, rather than angle-dependent measurements as was done previously. The method is applied to a simplified form of the transport equation that does not include scattering. The resulting procedure uses measured values of gamma-ray fluxes of discrete, characteristic energies to determine interface locations in a multilayer shield. The method was implemented with a Newton-Raphson optimization algorithm, and it worked very well in numerical one-dimensional spherical test cases. A more sophisticated optimization method would better exploit the potential of the inverse method.

Favorite, J. A. (Jeffrey A.); Sanchez, R. (Richard)

2004-01-01

371

Results of conservative surgery and radiation for mammographically detected ductal carcinoma in situ (DCIS)  

International Nuclear Information System (INIS)

Purpose: The role of conservative surgery and radiation for mammographically detected ductal carcinoma in situ (DCIS) is controversial. In particular, there is little data for outcome with radiation in a group of patients comparable to those treated with local excision and surveillance (mammographic calcifications ?2.5cm, negative resection margins, negative post biopsy mammogram). This study reports outcome of conservative surgery and radiation for mammographically detected DCIS with an emphasis on results in patients considered candidates for excision alone. Methods and Materials: >From 1983 to 1992, 110 women with mammographically detected DCIS (77% calcifications ± mass) and no prior history of breast cancer underwent needle localization and biopsy with (55%) or without a re excision and radiation. Final margins of resection were negative in 62%, positive 7%, close 11%, and unknown 20%. The median patient age was 56 years. The most common histologic subtype was comedo (54%), followed by cribriform (22%). The median pathologic tumor size was 8 mm (range 2 mm to 5 cm). Forty-seven percent of patients with calcifications only had a negative post biopsy mammogram prior to radiation. Radiation consisted of treatment to the entire breast (median 50.00 Gy) and a boost to the primary site (97%) for a median total dose of 60.40 Gy. Results: With a median follow-up of 5.3 years, three patients developed a recurrence in the treated breast. The median interval to recurrence was 8.8 years and all were invasive cancers. Two (67%) occurred outside the initial quadrant. The 5- and 10-year actuarial rates of recurrence were 1 and 15%. Cause-specific survival was 100% at 5 and 10 years. Contralateral breast cancer developed in two patients. There were too few failures for statistical significance to be achieved with any of the following factors: patient age, family history, race, mammographic findings, location primary, pathologic size, histologic subtype, re excision, or final margin status. However, young age, positive or close margins, and the presence of a mass without calcifications had a trend for an increased risk of recurrence. There were no recurrences in the subset of 16 patients who would be candidates for surveillance by Lagios' criteria. Conclusion: For selected patients, conservative surgery and radiation for mammographically detected DCIS results in a low risk of recurrence in the treated breast and 100% 5- and 10-year cause-specific survival. Improved mammographic and pathologic evaluation results in better patient selection and reduces the risk of the subsequent appearance of DCIS in the biopsy site. The identification of risk factors for an ipsilateral invasive breast recurrence is evolving.

1997-07-15

372

Laser-ultrasound spectroscopy apparatus and method with detection of shear resonances for measuring anisotropy, thickness, and other properties  

Energy Technology Data Exchange (ETDEWEB)

Apparatus and method for detecting shear resonances includes structure and steps for applying a radiation pulse from a pulsed source of radiation to an object to generate elastic waves therein, optically detecting the elastic waves generated in the object, and analyzing the elastic waves optically detected in the object. These shear resonances, alone or in combination with other information, may be used in the present invention to improve thickness measurement accuracy and to determine geometrical, microstructural, and physical properties of the object. At least one shear resonance in the object is detected with the elastic waves optically detected in the object. Preferably, laser-ultrasound spectroscopy is utilized to detect the shear resonances.

Levesque, Daniel (Terrebonne, CA); Moreau, Andre (St-Bruno-de-Montarville, CA); Dubois, Marc (Montreal, CA); Monchalin, Jean-Pierre (Montreal, CA); Bussiere, Jean (St-Bruno, CA); Lord, Martin (Beloeil, CA); Padioleau, Christian (Montreal, CA)

2000-01-01

373

The photochemical method for radiation abatement  

International Nuclear Information System (INIS)

This report reviews the underlying chemistry of the photochemical method for removal of radioiodines from air and evaluates the concept with respect to various applications in the nuclear industry. The method uses ultraviolet light (200-300 nm) to convert organic iodides (RI) to elemental iodine (I2). The I2 is then reacted with ozone to form solid iodine oxides (I4O9 or (I2O5), which deposit inside a scrubber. It is concluded that the method is applicable to large-scale systems and would have several advantages over conventional methods of radioiodine abatement

1984-01-01

374

Cationic membrane obtained by radiation grafting method  

Energy Technology Data Exchange (ETDEWEB)

A study has been made for the preparation of ion-containing reverse osmosis membranes by the radiation grafting of aqueous acrylic acid onto low density polyethylene films followed by alkaline treatment to confer ionic character in the prepared membranes. The appropriate reaction conditions were selected under which the graft polymerization was carried out successfully. In this grafting system ammonium ferrous sulphate (Mohr's salt) was used as inhibitor to minimize the homopolymerization of AAc, and a suitable concentration of the inhibitor to be added to the reaction medium was found to be 2.5 wt%. The effect of aqueous monomer concentration on the rate and degree of grafting was studied. The dependence of the grafting rate on the monomer concentration was found to be 0.8 order, i.e. almost first order dependence. It was also found that the irradiation atmosphere (air and nitrogen gas) had no significant effect on the grafting yield at given reaction conditions. The prepared graft copolymer films showed good thermal and chemical stability. Gel determination in the grafted films was also investigated and the results indicated that a crosslinked network structure may be formed. The extent of the gelled part in the graft copolymer increased as the degree of grafting increased.

Dessouki, A.M.; Hegazy, E.-S.A.; Shaker, M.M.

1987-01-01

375

The All Terrain Bio nano Gear for Space Radiation Detection System  

International Nuclear Information System (INIS)

[en] This paper discusses about the relevance of detecting space radiations which are very harmful and pose numerous health issues for astronauts. There are many ways to detect radiations, but we present a non-invasive way of detecting them in real-time while an astronaut is in the mission. All Terrain Bio-nano (ATB) gear system is one such concept where we propose to detect various levels of space radiations depending on their intensity and warn the astronaut of probable biological damage. A basic framework for radiation detection system which utilizes bio-nano machines is discussed. This radiation detection system is termed as 'radiation-responsive molecular assembly' (RMA) for the detection of space radiations. Our objective is to create a device which could detect space radiations by creating an environment equivalent to human cells within its structure and bio-chemically sensing the effects induced therein. For creating such an environment and further bio-chemically sensing space radiations bio-nano systems could be potentially used. These bio-nano systems could interact with radiations and signal based on the intensity of the radiations their relative biological effectiveness. Based on the energy and kind of radiation encountered, a matrix of signals has to be created which corresponds to a particular biological effect. The key advantage of such a design is its ability to interact with the radiation at e molecular scale; characterize its intensity based on energy deposition and relate it to the relative biological effectiveness based on the correspondence established through molecular structures and bond strengths of the bio-nano system

2007-01-30

376

Nuisance Source Population Modeling for Radiation Detection System Analysis  

Energy Technology Data Exchange (ETDEWEB)

A major challenge facing the prospective deployment of radiation detection systems for homeland security applications is the discrimination of radiological or nuclear 'threat sources' from radioactive, but benign, 'nuisance sources'. Common examples of such nuisance sources include naturally occurring radioactive material (NORM), medical patients who have received radioactive drugs for either diagnostics or treatment, and industrial sources. A sensitive detector that cannot distinguish between 'threat' and 'benign' classes will generate false positives which, if sufficiently frequent, will preclude it from being operationally deployed. In this report, we describe a first-principles physics-based modeling approach that is used to approximate the physical properties and corresponding gamma ray spectral signatures of real nuisance sources. Specific models are proposed for the three nuisance source classes - NORM, medical and industrial. The models can be validated against measured data - that is, energy spectra generated with the model can be compared to actual nuisance source data. We show by example how this is done for NORM and medical sources, using data sets obtained from spectroscopic detector deployments for cargo container screening and urban area traffic screening, respectively. In addition to capturing the range of radioactive signatures of individual nuisance sources, a nuisance source population model must generate sources with a frequency of occurrence consistent with that found in actual movement of goods and people. Measured radiation detection data can indicate these frequencies, but, at present, such data are available only for a very limited set of locations and time periods. In this report, we make more general estimates of frequencies for NORM and medical sources using a range of data sources such as shipping manifests and medical treatment statistics. We also identify potential data sources for industrial source frequencies, but leave the task of estimating these frequencies for future work. Modeling of nuisance source populations is only useful if it helps in understanding detector system performance in real operational environments. Examples of previous studies in which nuisance source models played a key role are briefly discussed. These include screening of in-bound urban traffic and monitoring of shipping containers in transit to U.S. ports.

Sokkappa, P; Lange, D; Nelson, K; Wheeler, R

2009-10-05

377

Laser Doppler echo signal detection method  

Science.gov (United States)

The coherent lidar system for speed measurement and the characteristics of the echo signal are discussed. And the principle and the advantages of the digital quadrature transform are analyzed. A digital quadrature detection scheme based on polyphase filter for coherent lidar system for speed measurement is presented by using the idea of software radio. Firstly the amplified analog signal is sampled to digital signal, and then is re-sampled with parity, time-aligned by delay filtering, finally the signal is divided into in-phase component and quadrature component. The scheme can be used to decrease the hardware complexity of system to a large extent, to avoid aliasing between the positive and the negative spectrums, to improve the SNR, and to obtain the signal in the quadrature form so as to fit the follow-up processing. Simulations and experiments indicate that the scheme is capable of resisting the noise compared with the traditional methods and is prone to real-time implementation, which, in turn, makes a contribution to greatly improve the performance of coherent Doppler lidar system for speed measurement and to orient the direction of a moving target.

Wang, Jiqiang; Zhang, Chunxi; Feng, Di; Ou, Pan; Tian, Lun

2009-05-01

378

Methods of NO detection in exhaled breath.  

UK PubMed Central (United Kingdom)

There is still an unexplored potential for exhaled nitric oxide (NO) in many clinical applications. This study presents an overview of the currently available methods for monitoring NO in exhaled breath and the use of the modelling of NO production and transport in the lung in clinical practice. Three technologies are described, namely chemiluminescence, electrochemical sensing and laser-based detection with their advantages and limitations. Comparisons are made in terms of sensitivity, time response, size, costs and suitability for clinical purposes. The importance of the flow rate for NO sampling is discussed from the perspective of the recent recommendations for standardized procedures for online and offline NO measurement. The measurement of NO at one flow rate, such as 50 ml s(-1), can neither determine the alveolar site/peripheral contribution nor quantify the difference in NO diffusion from the airways walls. The use of NO modelling (linear or non-linear approach) can solve this problem and provide useful information about the source of NO. This is of great value in diagnostic procedures of respiratory diseases and in treatment with anti-inflammatory drugs.

Cristescu SM; Mandon J; Harren FJ; Meriläinen P; Högman M

2013-03-01

379

Unruh effect as particular Frenet-Serret vacuum radiation and detection proposals  

CERN Document Server

The paradigmatic Unruh radiation is an ideal and simple case of stationary scalar vacuum radiation patterns related to worldlines defined as Frenet-Serret curves. We briefly review the corresponding body of theoretical literature as well as the proposals that have been suggested to detect these types of quantum field radiation patterns

Rosu, H C

2003-01-01

380

Method research on the calculation atmospheric path radiation in foggy weather  

Science.gov (United States)

Quantitative research of atmospheric path radiation and object reflectance radiation has been paid much attention and the research is significant content for atmospheric correction due to spacecraft remote sensing detection further studied. Because of the calculation for atmospheric path radiation depended on complex programs such as MODTRAN, the programs are very difficult to understand and it will be waste most time to call them. Thus, the model for atmospheric path radiation is set up to obtain the exact value of atmospheric path radiation fleetly and conveniently, which is helpful for actual significance on infrared target tracking, infrared target detecting and infrared target imaging. Based on the theory of atmospheric radiation transmission and atmospheric window, this paper comprehensively considers how to calculate optical depth, slant path and the influence in foggy weather, and establishes complete models and calculation method of atmospheric boundary layer atmospheric path radiation of 3~5?m. Compared the result of this MATLAB program for the models with the result of PcModWin5, relative error is within 5%. It provides theoretical foundation for design and evaluation of infrared systems.

Gu, Ji-Lin; Xu, Wen-Hai

2011-06-01

 
 
 
 
381

Optical fiber detectors as in-vivo dosimetry method of quality assurance in radiation therapy  

International Nuclear Information System (INIS)

[en] A new in-vivo dosimetry system has been under development for some time using radio luminescent phosphors. These phosphors are activated, metal ion doped glasses (Ex: Cu1± doped quartz fiber), have excellent optical transparency and offer several potential advantages for radiation dosimetry; including: small size, high sensitivity, linearity of dose response insensitivity to electromagnetic interference. The utility of these phosphors as a detection modality has been limited in real-time dosimetry applications due to the production of Cerenkov radiation in the carrier fiber, which produces a contaminant signal proportional to dose rate as well as the size of the radiation field. One possible method for eliminating this signal is using an electronic gating signal from the accelerator to delay data acquisition during the actual beam pulse, when Cerenkov radiation is produced. Due to the intrinsic properties of our particular scintillator, this method offers the best mechanism for eliminating Cerenkov noise, while retaining the ability to detect individual beam pulses. The dosimeter was tested using an external beam radiotherapy machine that provided pulses of 6 MeV x-rays. Gated detection was used to discriminate the signal collected during the radiation pulses, which included contributions from Cerenkov radiation and native fiber fluorescence, from the signal collected between the radiation pulses, which contained only the long-lived phosphorescence from the Cu1± doped fused quartz detector. Gated detection of the phosphorescence provided accurate, real-time dose measurements that were linear with absorbed dose, independent of dose rate and that were accurate for all field sizes studied. (author)

2004-01-01

382

Development of detection methods for irradiated foods  

Energy Technology Data Exchange (ETDEWEB)

In 1999, we have been studied (1) on the detection of irradiated foods by ESR spectroscopy, by thermoluminescence, and by viscometry for physical measurements, (2) on the detection of hydrocarbons and 2-alkylcyclobutanones derived from fatty foods by GC/MS for chemical measurements, (3) on the screening and detection of irradiated foods by Comet assay and immunochemical (ELISA) technique for biological or biochemical measurements.

Yang, Jae Seung; Nam, Hye Seon; Oh, Kyong Nam; Woo, Si Ho; Kim, Kyeung Eun; Yi, Sang Duk; Park, Jun Young; Kim, Kyong Su; Hwang, Keum Taek

2000-04-01

383

Method of and device for snore detection  

UK PubMed Central (United Kingdom)

The present invention provides a snore detection device comprising a pressure sensor for detecting vibration generated by the human body with respiration, a sound sensor for detecting sound generated by the human body with respiration, and a judging circuit for judging the occurrence of snoring based on output signals of the two sensors. The judging circuit detects a peak occurrence time in variations generated by the output signal of the pressure sensor and a peak occurrence time in variations generated by the output signal of the sound sensor, to judge whether snoring occurs based on the peak occurrence times, respectively, of vibration and sound.

NODA SATOSHI; MINAMIURA TAKESHI; SAKAI HIDETAKA

384

Lanthanum halide nanoparticle scintillators for nuclear radiation detection  

Energy Technology Data Exchange (ETDEWEB)

Nanoparticles with sizes <10 nm were fabricated and characterized for their nanocomposite radiation detector properties. This work investigated the properties of several nanostructured radiation scintillators, in order to determine the viability of using scintillators employing nanostructured lanthanum trifluoride. Preliminary results of this investigation are consistent with the idea that these materials have an intrinsic response to nuclear radiation that may be correlated to the energy of the incident radiation.

Guss, Paul; Guise, Ronald [Remote Sensing Laboratory, P.O. Box 98521, M/S RSL-48, Las Vegas, Nevada 89193 (United States); Yuan Ding [National Security Technologies, LLC, Los Alamos Operations, P.O. Box 809, M/S LAO/C320, Los Alamos, New Mexico 87544 (United States); Mukhopadhyay, Sanjoy [Remote Sensing Laboratory-Andrews, Building 1783, Arnold Avenue Andrews AFB, Maryland 20762 (United States); O' Brien, Robert; Lowe, Daniel [University of Nevada, Las Vegas, 4505 S. Maryland Parkway, Las Vegas, Nevada 89154 (United States); Kang Zhitao; Menkara, Hisham [Georgia Tech Research Institute, 925 Dalney St., Atlanta, Georgia 30332 (United States); Nagarkar, Vivek V. [RMD, Inc., 44 Hunt Street, Watertown, Massachusetts 02472 (United States)

2013-02-14

385

Radiation detection system for embarkations; Sistema de deteccao de radiacao nacionalizado para embarcacoes  

Energy Technology Data Exchange (ETDEWEB)

A nuclear radiation detection system is developed in order to use in frigate for continuous monitoring of ambient (water and air) radiation levels. The detection assembly consists of plastic scintillation detector and ionization chamber. (author) 6 refs., 8 figs., 4 tabs.

Morgado, Mario Monteiro [ELETROBRAS Termonuclear (ELETRONUCLEAR), Angra do Reis, RJ (Brazil); Moraes, Marco Antonio P.V. de; Madi Filho, Tufic; Omi, Nelson Minoru [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil)

1999-11-01

386

Development of thin dosemeters of CaSO4: Dy for beta radiation detection  

International Nuclear Information System (INIS)

[en] Thin pellets of CaSO: Dy (0,20mm) were produced and tested in beta radiation fields. The Thermolumiscent (TL) characteristics studied were sensitivity, reproducibility, lower detection limit, linearity of TL response with absorved dose energy dependence. The results show the usefulness of this thin pellets in beta radiation detection. (Author)

1987-01-01

387

Development of Remote Control Laboratory for Radiation Detection via Internet  

International Nuclear Information System (INIS)

[en] The role of experiments in science education is essential for understanding the natural phenomena and principle related to a subject. Therefore, the remote control experiment via Internet is one of key solution for distance learners in science education. The remote experiments are also necessary for the time-consuming experiment which takes several days, collaborative experiment between distance learners, expensive laboratory equipment which is not usually available to students, experimental procedure which is dangerous, etc. In this study, we have developed a general method for a remote control laboratory system using internet and interface techniques. It is possible for students to learn the nuclear physics to control the real instruments and conduct physics experimentation with internet techniques. We proposed the remote control radiation measurement system as a sample application. This system could be useful for the monitoring near a nuclear power plants in order to improve the environment data credibility to the public

2002-01-01

388

Approximate design calculation methods for radiation streaming in shield irregularities  

Energy Technology Data Exchange (ETDEWEB)

Investigation and assessment are made for approximate design calculation methods of radiation streaming in shield irregularities. Investigation is made for (1) source, (2) definition of streaming radiation components, (3) calculation methods of streaming radiation, (4) streaming formulas for each irregularity, (5) difficulties in application of streaming formulas, etc. Furthermore, investigation is made for simple calculation codes and albedo data. As a result, it is clarified that streaming calculation formulas are not enough to cover various irregularities and their accuracy or application limit is not sufficiently clear. Accurate treatment is not made in the formulas with respect to the radiation behavior for slant incidence, bend part, offset etc., that results in too much safety factors in the design calculation and distrust of the streaming calculation. To overcome the state and improve the accuracy of the design calculation for shield irregularities, it is emphasized to assess existing formulas and develop better formulas based on systematic experimental studies. (author)

Miura, Toshimasa; Hirao, Yoshihiro [Ship Research Inst., Mitaka, Tokyo (Japan); Yoritsune, Tsutomu

1997-10-01

389

Optimization of radiation monitoring methods of environment  

International Nuclear Information System (INIS)

[en] Full text : Report is devoted to the substantiation of the ways to optimize methods of providing radioecological monitoring (RM) in Ukraine. For this purpose the design features of RM at different levels, the analysis of modern requirements for the RM, the methods for RM ensuring were considered in the dissertation, the use for instrumentation supply of laboratories of new simplified methods, that were developed in this paper, was proposed. This work proposed to strengthen radiobiological component of monitoring, the advantages and disadvantages of the proposed methods were analyzed. The research of the spatial and vertical distribution of radionuclides in soils of the most polluted part of the Chernobyl zone was conducted using the proposed methods. For the first time the parameters of vertical migration of the isotopes 154Eu, 238-240Pu and 241Am in soil profiles of Ch NPP close zone were calculated. The parameters of vertical migration of 90Sr, 137Cs were refined. The calculations of effective environmental and semi-refined periods of above mentioned isotopes for different soil types were conducted, the estimation of dose rates to biota was done, and radioecological characterization of the test sites of the cooling pond was conducted. The features of radioecology of birds, rodents and shrews, bats and amphibians were studied. The dose rates for these species were assessed and their compliance with 103 ICRP Guiding. The species differences in the pollution of wild rodents, insectivores, passerine birds, amphibians and bats on a large amount of factual material were estimated. The investigation of the radioecological contamination of the features of the urbanized landscape was conducted on the example of Pripyat silty. The practical significance of the work is that the developed methods of non radiochemical determination of radiostrontium activity, alpha emitting isotopes of plutonium, which can significantly hasten and facilitate the evaluation of the corresponding concentration radionuclides in the environment, and significantly reduce economic costs. The method of intra vital measurement of 90Sr in small animals opens up fundamentally new opportunities for researchers in radioecology and radiobiology

2012-01-01

390

Motion Sensor and Method for Detecting Motion.  

Science.gov (United States)

A motion sensor may detect linear and/or angular acceleration and/or angular velocity of a body relative to one axis, two orthogonal axes or three orthogonal axes. Movement of the body or reference structure may be detected relative to one or more spinnin...

M. E. Greene V. S. Trent

2004-01-01

391

Inertial confinement fusion method producing line source radiation fluence  

Energy Technology Data Exchange (ETDEWEB)

An inertial confinement fusion method in which target pellets are imploded in sequence by laser light beams or other energy beams at an implosion site which is variable between pellet implosions along a line. The effect of the variability in position of the implosion site along a line is to distribute the radiation fluence in surrounding reactor components as a line source of radiation would do, thereby permitting the utilization of cylindrical geometry in the design of the reactor and internal components.

Rose, Ronald P. (Peters Township, Washington County, PA)

1984-01-01

392

Apparatus and method for locating and quantifying or directing a source of ionizing radiation  

International Nuclear Information System (INIS)

An apparatus and method for locating or directing a source of ionizing radiation such as X-rays, gamma rays, alpha particles, beta particles, etc. are described. The preferred embodiment detects and locates abnormalities of the body such as ocular melanomas by detecting the emission of radiation from a melanoma which has absorbed a radioactive medium. The apparatus includes an ultrasound probe which emits ultrasonic waves along a first axis and detects a returned portion of the waves. The ultrasound probe is associated with a display which displays the returned portion of the waves in the time domain so that suspected abnormalities can be located. The ultrasound probe is used to guide a directional probe for detecting and quantifying ionizing radiation which is equipped with a focusing collimator having a focal point along a second axis. The two probes are supported so that the first and second axes converge at the focal point of the collimator. A range marker is associated with the ultrasonic detector which indicates the point of convergence of the axes on the ultrasonic display permitting guidance of the radiation detecting probe to the suspected abnormality

1976-01-01

393

Detection of explosives on the basis of TNA-method  

International Nuclear Information System (INIS)

The possibility of applying the counting efficiency methods in the algorithm of the arrangement program intended for searching the explosive substances through the neutron radiation analysis method is discussed. The capture radiation spectra registered on the real facility model, and the response calculational functions for the 6 and 10.9 MeV quanta are presented. The possibility of applying the considered methods in the task of the explosive substances identification is described

2005-01-01

394

Imaginary-time method for radiative capture reaction rate  

CERN Document Server

We propose a new computational method for astrophysical reaction rate of radiative capture process. In the method, an evolution of a wave function is calculated along the imaginary-time axis which is identified as the inverse temperature. It enables direct evaluation of reaction rate as a function of temperature without solving any scattering problem. The method is tested for two-body radiative capture reaction, ${^{16}{\\rm O}}(\\alpha,\\gamma){^{20}{\\rm Ne}}$, showing that it gives identical results to that calculated by the ordinary procedure. The new method will be suited for calculation of triple-alpha radiative capture rate for which an explicit construction of the scattering solution is difficult.

Yabana, Kazuhiro

2012-01-01

395

COMPARISON OF MONTE CARLO METHODS FOR NONLINEAR RADIATION TRANSPORT  

International Nuclear Information System (INIS)

Five Monte Carlo methods for solving the nonlinear thermal radiation transport equations are compared. The methods include the well-known Implicit Monte Carlo method (IMC) developed by Fleck and Cummings, an alternative to IMC developed by Carter and Forest, an ''exact'' method recently developed by Ahrens and Larsen, and two methods recently proposed by Martin and Brown. The five Monte Carlo methods are developed and applied to the radiation transport equation in a medium assuming local thermodynamic equilibrium. Conservation of energy is derived and used to define appropriate material energy update equations for each of the methods. Details of the Monte Carlo implementation are presented, both for the random walk simulation and the material energy update. Simulation results for all five methods are obtained for two infinite medium test problems and a 1-D test problem, all of which have analytical solutions. Conclusions regarding the relative merits of the various schemes are presented.

2001-01-01

396

Sectoring method for cosmic radiation shielding calculation for LEO satellite  

International Nuclear Information System (INIS)

One of an approximate calculation model (sectoring method) is developed for a cosmic radiation shielding in satellite. Shielding calculation is performed for KITSAT-1 at the assumed SAA (South Atlatic Anomaly) location with AP-8 model radiation spectrum. When sectoring method is applied, calculation error is expected compared with 3-D detailed geometry calculation because of straight knock-on assumption neglecting the deflection of incident proton. However, sectoring method shows good agreements with 3-dimensional detailed Monte Carlo calculation in two TID detector locations.

2002-01-01

397

Method for non-invasive detection of ocular melanoma  

Energy Technology Data Exchange (ETDEWEB)

There is described an apparatus and method for diagnosing ocular cancer that is both non-invasive and accurate which comprises two radiation detectors positioned before each of the patient's eyes which will measure the radiation level produced in each eye after the administration of a tumor-localizing radiopharmaceutical such as gallium-67.

Lambrecht, Richard M. (Quogue, NY); Packer, Samuel (Floral Park, NY)

1984-01-01

398

Comparison of Methods for Oscillation Detection : case study  

DEFF Research Database (Denmark)

This paper compares a selection of methods for detecting oscillations in control loops. The methods are tested on measurement data from a coal-fired power plant, where some oscillations are occurring. Emphasis is put on being able to detect oscillations without having a system model and without using process knowledge. The tested methods show potential for detecting the oscillations, however, transient components in the signals cause false detections as well, motivating usage of models in order to remove the expected signals behavior.

Odgaard, Peter Fogh; Trangbæk, Klaus

2006-01-01

399

System and method for detecting cells or components thereof  

Energy Technology Data Exchange (ETDEWEB)

A system and method for detecting a detectably labeled cell or component thereof in a sample comprising one or more cells or components thereof, at least one cell or component thereof of which is detectably labeled with at least two detectable labels. In one embodiment, the method comprises: (i) introducing the sample into one or more flow cells of a flow cytometer, (ii) irradiating the sample with one or more light sources that are absorbed by the at least two detectable labels, the absorption of which is to be detected, and (iii) detecting simultaneously the absorption of light by the at least two detectable labels on the detectably labeled cell or component thereof with an array of photomultiplier tubes, which are operably linked to two or more filters that selectively transmit detectable emissions from the at least two detectable labels.

Porter, Marc D. (Ames, IA); Lipert, Robert J. (Ames, IA); Doyle, Robert T. (Ames, IA); Grubisha, Desiree S. (Corona, CA); Rahman, Salma (Ames, IA)

2009-01-06

400

High Density Nano-Electrode Array for Radiation Detection  

International Nuclear Information System (INIS)

Bulk single crystals of Cd1-xZnxTe (x=0.04 to x=0.2) compound semiconductor is used for room temperature radiation detection. The production of large volume of Cd1-xZnxTe with low defect density is expensive. As a result there is a growing research interest in the production of nanostructured compound semiconductors such as Cd1-xZnxTe in an electrochemical route. In this investigation, Cd1-xZnxTe ternary compound semiconductor, referred as CZT, was electrodeposited in the form of nanowires onto a TiO2 nanotubular template from propylene carbonate as the non-aqueous electrolyte, using a pulse-reverse electrodeposition process at 130 C. The template acted as a support in growing ordered nanowire of CZT which acts as a one dimensional conductor. Cyclic Voltammogram (CV) studies were conducted in determining the potentials for the growth of nanowires of uniform stoichiometry. The morphologies and composition of CZT were characterized by using SEM, TEM and XRD. The STEM mapping carried out on the nanowires showed the uniform distribution of Cd, Zn and Te elements. TEM image showed that the nanowires were polycrystalline in nature. The Mott-Schottky analysis carried on the nanowires showed that the nanowires were a p-type semiconductor. The carrier density, band gap and resistivity of the Cd0.9Zn0.1Te nanowires were 4.29 x 1013 cm-3, 1.56 eV and 2.76 x 1011 (Omega)-cm respectively. The high resistivity was attributed to the presence of deep defect states such as cadmium vacancies or Te antisites which were created by the anodic cycle of the pulse-reverse electrodeposition process. Stacks of series connected CZT nanowire arrays were tested with different bias potentials. The background current was in the order of tens of picoamperes. When exposed to radiation source Amerecium-241 (60 KeV, 4 (micro)Ci), the stacked CZT nanowires arrays showed sensing behavior. The sensitivity of the nanowire arrays increased as the number of stacks increased. The preliminary results indicate that the CZT nanowire arrays can be used as a potential X-ray and low energy gamma ray detector material at room temperature with a much low bias potential (0.7-4V) as against 300-500 V applied in the commercial bulk detector materials.

2010-01-01

 
 
 
 
401

Simulation Analysis of Some Outlier Detection Methods.  

Science.gov (United States)

Outlier detection techniques when interest is on bivariate observations are presented. The techniques employed are derived from three different areas: (1) the influence function for the correlation coefficient, (2) regression diagnostics, and (3) principa...

D. J. Downing J. E. Pierce

1981-01-01

402

Interpolation methods and their use in radiation protection  

International Nuclear Information System (INIS)

The presentation summarizes results of using various interpolation methods for getting spatial data from point measurements. These methods were evaluated within the State Office for Nuclear Safety (SONS) Science and Research Project No. 2/2008 'Methods and Measures to Limit Generation and Liquidation of Consequences of Radioactive Matter Misuse by Terrorists'. Several field tests in which the short life-time radioactive matter was released by explosion were realized and the measured data were processed. The essential goal is to find the most realistic method for radiation events assessment. Within the research project, three methods were used: Multilevel B-Spline, Triangulation and Kriging, using freely available SAGA GIS software. The best solution for this sort of radiation events appears to be the Multilevel B-Spline method. It is quick and produces good quality output data comparable with the much slower Kriging method and allows extrapolation in contrast to Triangulation. (author)

2008-01-01

403

GaN heterostructures for biosensing and radiation detection  

International Nuclear Information System (INIS)

[en] In this thesis I show the results from our investigation of the interface between gallium nitride wide bandgap semiconductor heterostructures and (bio)molecular systems on their surfaces for biosensing, bioelectronics, and photoelectric applications, with a large emphasis on the processes arising from high energy ionizing irradiation, including heterostructure photoelectric gain mechanisms. Wide bandgap semiconductors, such as gallium nitride, have received increasing attention as potential components in advanced organic/inorganic hybrid systems. Working to further this topic, we determine a new semiconductor alignment required for low energy photo-induced charge transfer ionization of alkyl chains well below the energy normally required for molecular cleavage, show original results of the influence of binding methods on enzyme functionality in conjunction with a novel electrochemical and environmental control system and demonstrate new possibilities to significantly improve upon pH measurements through the use of high sensitivity devices. Furthermore, based on the extension of this work to support future studies of radiation effects on cell systems, we present a detailed characterization of new simultaneous chemical sensing and ionizing radiation dosimetry using single devices. We found that their pH sensitivity was retained during X-ray irradiation and that the fundamental characteristics can be used to separate the irradiation signal from the pH response without compromising operational stability. These data provide clear indications of the separate response mechanism tied to the presence of a two-dimensional electron gas channel. Here, we found new results exhibiting exceptionally high gains and independence of the well-known persistent photoconductivity for soft X-rays and high energy particles in the ultralow dose-rate regime. This material system provides the capability for high sensitivity and resolution real time monitoring, which is competitive with and complements state-of-the-art detectors. Thus, is extremely promising for future applications ranging from advanced organic/inorganic hybrid systems to medical imaging.

2012-01-01

404

GaN heterostructures for biosensing and radiation detection  

Energy Technology Data Exchange (ETDEWEB)

In this thesis I show the results from our investigation of the interface between gallium nitride wide bandgap semiconductor heterostructures and (bio)molecular systems on their surfaces for biosensing, bioelectronics, and photoelectric applications, with a large emphasis on the processes arising from high energy ionizing irradiation, including heterostructure photoelectric gain mechanisms. Wide bandgap semiconductors, such as gallium nitride, have received increasing attention as potential components in advanced organic/inorganic hybrid systems. Working to further this topic, we determine a new semiconductor alignment required for low energy photo-induced charge transfer ionization of alkyl chains well below the energy normally required for molecular cleavage, show original results of the influence of binding methods on enzyme functionality in conjunction with a novel electrochemical and environmental control system and demonstrate new possibilities to significantly improve upon pH measurements through the use of high sensitivity devices. Furthermore, based on the extension of this work to support future studies of radiation effects on cell systems, we present a detailed characterization of new simultaneous chemical sensing and ionizing radiation dosimetry using single devices. We found that their pH sensitivity was retained during X-ray irradiation and that the fundamental characteristics can be used to separate the irradiation signal from the pH response without compromising operational stability. These data provide clear indications of the separate response mechanism tied to the presence of a two-dimensional electron gas channel. Here, we found new results exhibiting exceptionally high gains and independence of the well-known persistent photoconductivity for soft X-rays and high energy particles in the ultralow dose-rate regime. This material system provides the capability for high sensitivity and resolution real time monitoring, which is competitive with and complements state-of-the-art detectors. Thus, is extremely promising for future applications ranging from advanced organic/inorganic hybrid systems to medical imaging.

Howgate, John D.

2012-12-11

405

Radiation shielding material and construction method  

International Nuclear Information System (INIS)

[en] Fillers such as concrete, mortar, cement, and soil cement are placed in a plurality of layers. Net-like members are buried between adjacent layers, and the fillers are integrally cured by way of the meshes of the net-like members. A synthetic resin net, a metal net or expand metal can be used for the net-like member. Since operation for placing the fillers of different qualities to the plurality of layers can be conducted at once, and it is enough that only the outer mold frame may be removed after curing in the construction method of the present invention, occurrence of gaps due to shrinkage can be prevented. (T.M.)

1995-01-31

406

Handbook of engineering control methods for occupational radiation protection  

Energy Technology Data Exchange (ETDEWEB)

Sources of ionizing and non-ionizing radiation are widely used in industrial, medical, military, and other applications. In the workplace, the task of assuring the safety of workers exposed to radiation sources is generally assigned to the safety professional, industrial hygienist, or an engineer in some other discipline. Rarely do employers outside the nuclear industry have the luxury of a staff health physicist in the workplace. Consultants may be called in to provide initial assessments of the hazards and to assist with complex problems, but the day-to-day problem solving is usually a function of the safety professional or other professional with the responsibility for safety. The primary purpose of this book is to provide a practical reference for safety professionals that addresses the application of ionizing and non-ionizing radiation protection standards and the quantitative methods for evaluating and designing engineering controls to meet those standards. Although the emphasis of this book is on control methods, it is necessary to understand the physical nature of the radiation exposure, its units of measure, and its biological effects in order to apply the appropriate control methods. Consequently, a brief treatment of these topics precedes the discussion of control methods for each type of radiation exposure.

Orn, M.K.

1992-01-01

407

Rain-Induced Increase in Background Radiation Detected by Radiation Portal Monitors  

Energy Technology Data Exchange (ETDEWEB)

A complete understanding of both the steady state and transient background measured by Radiation Portal Monitors (RPMs) is essential to predictable system performance, as well as maximization of detection sensitivity. To facilitate this understanding, a test bed for the study of natural background in RPMs has been established at the Oak Ridge National Laboratory. This work was performed in support of the Second Line of Defense Program's mission to detect the illicit movement of nuclear material. In the present work, transient increases in gamma ray counting rates in RPMs due to rain are investigated. The increase in background activity associated with rain, which has been well documented in the field of environmental radioactivity, originates from the atmospheric deposition of two radioactive daughters of radon-222, namely lead-214 and bismuth-214 (henceforth {sup 222}Rn, {sup 214}Pb and {sup 214}Bi). In this study, rainfall rates recorded by a co-located weather station are compared with RPM count rates and High Purity Germanium spectra. The data verifies these radionuclides are responsible for the dominant transient natural background fluctuations in RPMs. Effects on system performance and potential mitigation strategies are discussed.

Hausladen, Paul [ORNL; Blessinger, Christopher S [ORNL; Guzzardo, Tyler [ORNL; Livesay, Jake [ORNL

2012-07-01

408

Calibration method of radiation monitoring system at TQNPC  

International Nuclear Information System (INIS)

[en] The calibration methods and calibration device for standard monitor of radioactive particulate, iodine, noble gas and so on are not yet set up at home. On consideration of the present situation of the radiation monitoring system at the Third Qinshan Nuclear Power Co. Ltd., we have studied the calibration method of these radiation monitoring instruments used for measuring the waste liquid, particulate, iodine and noble gas produced during the operation of nuclear reactor. Through the check against these instruments during the No. 202 and No. 103 overhaul, we got initially the method of the calibration and obtained the transfer coefficient of calibration when secondary solid sources are used for calibration. Through the testing and calibration, the credibility of the radiation monitoring system is enhanced. And at the same time, the problems existing in the calibration are discussed. (authors)

2009-01-01

409

Alterations of mitochondrial DNA: a method for the detection of irradiated beef liver  

International Nuclear Information System (INIS)

The study of the radio degradation of DNA is one of a number of phenomena being investigated to develop methods for identifying irradiated foods. The specific behaviour under radiation of the mitochondrial DNA from beef liver gives the possibility of detecting if the product has been irradiated or not. An identification method could finally be developed. The appraisal of the mitochondrial supercoiled DNA fraction constitutes an unambiguous detection test for beef liver irradiation. A total of 120 different samples were irradiated at 5 different doses. The dose limit of detection is lower than 2 kGy. No effects due to storage conditions were observed. (Author).

1992-01-01

410

Leak detection method and method of manufacturing system to be detected  

International Nuclear Information System (INIS)

In a leak detection method, a pH value of water or steams leaked from a system in which a storage vessel for containing water or steams is surrounded by concretes is measured and detected. Further, the surface of the system which has a possibility of causing dew condensation is applied with coating to suppress the contact between condensed water with the concretes. Alternatively, an air layer is formed, the humidity of which is controlled not higher than that of ambient air when the temperature of the air layer is made equal with that of the surface of the system to suppress or prevent occurrence of condensated water on the surface. (N.H.).

1994-06-08

411

Methods and procedures for external radiation dosimetry at ORNL  

International Nuclear Information System (INIS)

[en] Procedures, methods, materials, records, and reports used for accomplishing the personnel, external radiation monitoring program at Oak Ridge National Laboratory are described for the purpose of documenting what is done now for future reference. This document provides a description of the methods and procedures for external radiation metering, monitoring, dosimetry, and records which are in effect at ORNL July 1, 1981. This document does not include procedures for nuclear accident dosimetry except insofar as routine techniques may apply also to nuclear accident dosimetry capability

1981-01-01

412

Method for decreasing radiation load in puva therapy  

Energy Technology Data Exchange (ETDEWEB)

An improved method is described for treating a psoriatic subject undergoing treatment with a psoralen in conjection with ultraviolet A radiation of from wavelength of 3200 to 4000 angstroms. The improved method comprises prior to initiation of the treatment, pretreating the subject for a period of from 4 to 10 days with an effective amount of an anti-psoriatic polyene compound, and thereafter initiating the treatment with a psoralen in conjunction with ultraviolet A radiation and continuing the treatment concurrently with the administration of the anti-psoriatic polyene compound.

Wolff, K.

1987-02-10

413

Review on Islanding Detection Methods for Photovoltaic Inverter  

Directory of Open Access Journals (Sweden)

Full Text Available Solar power generation, which is regarded as an ideal environment-friendly manner for power generation, is getting more and more attention. When photovoltaic inverter is connected to the grid?the island effect is a special problem to confront. This paper briefly analyzes the island effects and makes a summary of both domestic and external research progress concerning islanding detection methods; the islanding detection methods can be divided into two classes: one is grid-side detection; the other is local detection. The local detection is generally divided into passive methods and active methods. The theory of advantages and disadvantages of those methods are briefly introduced in this paper. At the end of the paper, to deal with the disadvantages of those methods that are mentioned, it proposes the research direction for deeper study of islanding detection methods.

Xi Zhongmei; Zhang Zhiming; Wang Ranran; Zhang Chuanyang; Liu Mochen; Wang Tao

2013-01-01

414

ESR based detection method for irradiated dry fish, tomato soup powder and sweet-meats  

International Nuclear Information System (INIS)

Full text: Radiation Processing is increasingly being accepted as one of the most effective and economic method to treat agricultural and horticultural commodities for hygienization and disinfestation purposes and also in overcoming strict quarantine barriers in international trade. At present there is a growing concern about the presence of insecticides and pesticides and their residues in various foods, we consume. In view of this, irradiation, being a physical and cold process, emerges as the best bet towards having an uninterrupted supply of safe and quality food. The process has been endorsed as safe by several international and national bodies. A suitable detection method is however required to meet the basic requirements of consumers and law enforcement authorities, regulating the trade. Dried, sliced Pollack and File fishes were subjected to radiation dose of 4 kGy for elimination of coliforms and for improvement in quality standards during storage. Bones separated served as sample source for ESR based detection method of the radiation treatment. Bones with hard crystalline matrix served as trap for free radicals and facilitated evolution of an ESR based detection method. It showed a linear dose response curve at ?=2.0037, whereas, those from non-irradiated fish fillets failed to show any ESR signal. Re-irradiation helped in calculation of dose delivered to dried fishes. Sachets -containing tomato soup ingredients, including sugars exposed to 0.25 to 2 kGy gamma radiation doses for hygienization and quarantine purposes were used in the experiments. In-pack sugar crystals served as free radicals trap for ESR based detection method for radiation hygienized tomato soup powder. Similarly, it was observed that radiation hygienization of sugar bearing sweet-meats, like Peda (an evaporated milk preparation), Petha (a sugar syrup soaked vegetable preparation) and dry fruits like raisins could be detected using ESR. Suitable methodology was developed to detect radiation specific signals in minute amount of samples Thus, free radicals generated in fish bones and in sugar crystals of soups and sweet-meats were found to be specific to radiation dose and were fairly stable for analytical applications

2003-01-01

415

Detection of volatile biomarkers of therapeutic radiation in breath.  

UK PubMed Central (United Kingdom)

Breath testing could provide a rational tool for radiation biodosimetry because radiation causes distinct stress-producing molecular damage, notably an increased production of reactive oxygen species. The resulting oxidative stress accelerates lipid peroxidation of polyunsaturated fatty acids, liberating alkanes and alkane metabolites that are excreted in the breath as volatile organic compounds (VOCs). Breath tests were performed before and after radiation therapy over five days in 31 subjects receiving daily fractionated doses: 180-400 cGy d(-1) standard radiotherapy (n = 26), or 700-1200 cGy d(-1) high-dose stereotactic body radiotherapy (n = 5). Breath VOCs were assayed using comprehensive two-dimensional gas chromatography time-of-flight mass spectrometry. Multiple Monte Carlo simulations identified approximately 50 VOCs as greater-than-chance biomarkers of radiation on all five days of the study. A consistent subset of 15 VOCs was observed at all time points. A radiation response function was built by combining these biomarkers and the resulting dose-effect curve was significantly elevated at all exposures ?1.8 Gy. Cross-validated binary algorithms identified radiation exposures ?1.8 Gy with 99% accuracy, and ?5 Gy with 78% accuracy. In this proof of principal study of breath VOCs, we built a preliminary radiation response function based on 15 VOCs that appears to identify exposure to localized doses of 1.8 Gy and higher. VOC breath testing could provide a new tool for rapid and non-invasive radiation biodosimetry.

Phillips M; Byrnes R; Cataneo RN; Chaturvedi A; Kaplan PD; Libardoni M; Mehta V; Mundada M; Patel U; Ramakrishna N; Schiff PB; Zhang X

2013-09-01

416

Detecting Radiation-Induced Injury Using Rapid 3D Variogram Analysis of CT Images of Rat Lungs.  

UK PubMed Central (United Kingdom)

RATIONALE AND OBJECTIVES: To investigate the ability of variogram analysis of octree-decomposed computed tomography (CT) images and volume change maps to detect radiation-induced damage in rat lungs. MATERIALS AND METHODS: The lungs of female Sprague-Dawley rats were exposed to one of five absorbed doses (0, 6, 9, 12, or 15 Gy) of gamma radiation from a Co-60 source. At 6 months postexposure, pulmonary function tests were performed and four-dimensional (4D) CT images were acquired using a respiratory-gated microCT scanner. Volume change maps were then calculated from the 4DCT images. Octree decomposition was performed on CT images and volume change maps, and variogram analysis was applied to the decomposed images. Correlations of measured parameters with dose were evaluated. RESULTS: The effects of irradiation were not detectable from measured parameters, indicating only mild lung damage. Additionally, there were no significant correlations of pulmonary function results or CT densitometry with radiation dose. However, the variogram analysis did detect a significant correlation with dose in both the CT images (r = -0.57, P = .003) and the volume change maps (r = -0.53, P = .008). CONCLUSION: This is the first study to use variogram analysis of lung images to assess pulmonary damage in a model of radiation injury. Results show that this approach is more sensitive to detecting radiation damage than conventional measures such as pulmonary function tests or CT densitometry.

Jacob RE; Murphy MK; Creim JA; Carson JP

2013-10-01

417

Method of Object Detection for Mobile Robot  

Directory of Open Access Journals (Sweden)

Full Text Available Problem statement: In general, there are two steps of object detection, which are object generation, where the locations of possible objects are in an image and object verification, where tests are performed to verify the presence of object in an image. Approach: The purpose of the proposed object recognition system was to detect the object which is in front the mobile robot so that it can send warnings to avoid possible collision. The information of detected objects can also help to control the robot to travel at an appropriate speed and direction to avoid possible collisions. Results: An object in an image was detected by the two steps of image generation and verification. When object localizations were hypothesized, sub-image of the object was extracted from the image. Gabor features extracted from the sub-image is input into the classifier to verify whether the hypothesized sub-image contain an object or not. Conclusion: Localizations of objects in image are generated and verified. Object generation was implemented by using horizontal and vertical edges on the way region of interest segmented by utilizing color information. The sub-images of object are verified by classifier trained on Gabor features of a training set of images.

Surachai Panich

2010-01-01