The threshold values of total absorbed dose for causing changes in tensile properties of a polyetherimide film and the limitations of the absorbed dose rate for accelerated-exposure evaluation of the effects of electron radiation in geosynchronous orbit w...

... Abstract : The effects of electron radiation on Ultem, a ... were studied for total absorbed doses from 1.0 kGy to 100 MGy at absorbed dose rates from ...

Values of the fast neutron absorbed dose rate in an ethylene absorber are given as a function of penetration distance in hydrogen. The dose rates were obtained by numerical integration of the product of the differential number spectrum and the ethylene conversion ...

... Title : Radiation Energy Absorbed by Human Phantoms ... DOSIMETERS, INSTRUMENTATION, IONIZATION CHAMBERS, DOSE RATE, RADIATION ...

... dose, Q is the quality factor, and N is the product of any other modifying factors such as those accounting for effects due to dose rate, dose ...

Four tables designed to permit rapid conversion from one to another of the units for absorbed dose, absorbed dose rate, energy, and power are given. (M.C.G.)

A measuring method and dose rate meter for beta -ray absorbed dose independent of the beta -ray maximum energy have been developed. To obtain constant dose sensitivity (counting rate per absorbed dose rate), a ...

rates from internal and external exposures. Internal dose rates are calculated using organism- and nuclide-specific bioaccumulation factors and absorbed energy fractions. External dose rates are calculated the outside the body are called external exposures; calculated ...

The threshold values of total absorbed dose for causing changes in tensile properties of a polyetherimide film and the limitations of the absorbed dose rate for accelerated-exposure evaluation of the effects of electron radiation in geosynchronous orbit were studied. Total ...

levels of radiation dose and/or dose rate for the duration of the mission. ... or the energy absorbed per unit mass. The most commonly used dose unit is the ...

The method used is briefly described: geometrical parametrization by a set of planes and photon transport simulation by Monte Carlo techniques. The whole-body absorbed dose rate and the maximum absorbed dose rate in the phantom representing the worker are...

A new extrapolation chamber is described, which is used as absolute standard for the determination of the absorbed beta radiation dose. The construction simulates a semi-infinite phantom and the absorbed dose to tissue was determined in tissue equivalent ...

The study was conducted to determine absorbed dose, dose-equivalent rates, and neutron spectra inside containment at nuclear power plants. The purpose of this study was: (1) measure dose-equivalent rates with various commercial types of rem meters, such a...

... effects of external reflectors by absorbing and scattering thermal neu- ... moderating experiments) broaden the pulse and reduce the dose rates ...

... over time assuming a constant charging rate..... ... A-2: Absorbed dose through material depth ...

... LOW ENERGY, SILICON, ARTIFICIAL SATELLITES, SECONDARY EMISSION, GOLD, BLACKBODY RADIATION, DOSE RATE, PHOTOELECTRIC ...

Apr 21, 2011 ... Depth Distribution of Absorbed Dose on the External Surface of Cosmos ... + Badhwar GD, Braby LA, Cucinotta FA, and Atwell W. Dose rate, ...

Equations for estimating the absorbed dose from assimilation of radionuclides in the body organs of humans are presented for several assumed conditions of ingestion rates that are considered applicable to the consumption of human foods following contamination by fallout in a nuclear war. The absorbed ...

A method and an instrument are, herein, disclosed for measuring the absorbed dose rate of beta-ray in sites of the human body. The instrument of this invention consists of a thin scintillator, a linear amplifier, a pulse selector having disposed in parallel therein a plurality of pulse height selection mechanisms for selectively ...

A method and an instrument are, herein, disclosed for measuring the absorbed dose rate of beta-rays in sites of the human body. The instrument of this invention consists of a filter, a thin scintillator, a photomultiplier tube, a linear amplifier, a discriminator having a plurality of pulse height selection potentiometers for ...

Absorbed radiation doses delivered to the whole-body, kidney, and liver by intravenous injections of As/sup 72/ in humans were calculated and compared with the doses from As/sup 74/. It is shown that for a given limiting dose to the kidney the use of As/sup 72/ permits lower whole-body ...

Human erythrocyte membrane damage under the impact of ? radiation on blood suspension is studied in a wide dose range (2�1000 Gy, irradiation dose rate 2.75 Gy/min). It is shown that the irradiation in the absorbed dose range from 600 Gy and higher results in hemolysis of erythrocytes ...

No accepted official protocol exists for the dosimetry of the Leksell Gamma Knife (GK) stereotactic radiosurgery device. Establishment of a dosimetry protocol has been complicated by the unique partial-hemisphere arrangement of 201 individual 60Co beams simultaneously focused on the treatment volume and by the rigid geometry of the GK unit itself. This article proposes an air kerma based dosimetry ...

Monte Carlo calculations of the absorbed dose delivered by point source gamma emitters to tissue equivalent phantoms were performed and the results are presented in tables that include that fraction of the emitted energy absorbed by the phantom. The use of these tables makes it possible to calculate gamma ...

A simple calorimetric dosimeter has been contrived to measure the radiation dose absorbed by di(2-ethylhexyl)phosphoric acid in irradiation with an electron or photon beam from a 60 MeV electron accelerator. The absorbed dose rate is related to the beam c...

Radiation dose rates from three thulium-170 oxide sources (20.7, 10.0 and 5.0 thermal watts) were measured through three thicknesses (1/4, 1/2 and 1 inch) of absorber by thermoluminescent dosimetry techniques. Absorber materials used were aluminium, stainless steel, lead, tungsten and depleted uranium. Resultant ...

A study on the effect of gamma radiation dose and dose rate on the yield of copper nanoparticles produced had been done. Its objective is to show the relationship between the absorbed doses with the yield of production. The copper sulphate solution is prepared with addition of ethanol as ...

In calculations of absorbed dose rates from experimental measurements of beta -transmission currents, the relationship can be reduced to a simple function of the beta emission and area of the irradiated sample. The beta current extrapolated to zero sample thickness divided by the weight of the sample gave the ...

This study assesses the outdoor gamma absorbed dose levels in air of the Adana's region. The measurements were taken from 130 different sample points in this area by Eberline Smart Portable (ESP-2) with SPA-6 plastic scintillation detector. The outdoor gamma absorbed dose rates order from 40 to ...

Surface absorbed dose rates from different hemispheric volumes of /sup 133/Xe have been measured directly with an extrapolation chamber. The results indicate that a linear relationship exists between the radius of the cloud volume and the surface absorbed dose rate for ...

If a large radioactive cloud is produced, sampling may require that an airplane traverse the cloud. A method to predict the absorbed dose to the aircrew from penetrating the radioactive cloud is needed. Dose rates throughout spherically symmetric Gaussian clouds of various sizes, and the ...

The calculation of absorbed dose rate of photons and neutrons for the linear source of 252Cf with the active length of 2 cm is presented. Monte Carlo code and neutron cross-section data processed from ENDF/B-6 library were used. The achieved values of the absorbed dose ...

... Accession Number : AD0672563. Title : A CALORIMETER WITH INTERCHANGEABLE ABSORBERS FOR ABSORBED DOSE ...

... So, x(t) is the average rate of aircraft loss in unit time at time t in the given mission due to ir- radiation ... tion is the radiation dose absorbed by the crew ...

... Title : MODELS FOR ESTIMATING THE ABSORBED DOSE FROM ASSIMILATION OF RADIONUCLIDES IN BODY ORGANS OF HUMANS,. ...

The specific activity of naturally occurring radionuclide 210Po in main species of the Black Sea fishes and some their organs were used for the calculation of absorbed and equivalent dose rates. The values of the dose in investigated fish depend on their ecological belonging. Maximum values of equivalent ...

A comparison was made between the effect of absorbed dose from /sup 210/ Po in tissues of rats treated and untreated with sodium 2-(2,3-dimercaptopropoxi) ethansulfonate (oxathiol). The rats were subcutaneously injected with 0.1 mu Ci of /sup 210/Po in the form of polonium nitrate. The oxathiol treatment led to considerable decreases of alpha ...

doses due to external radiation have been extensively applied after exposures due to the production values of the absorbed dose rate in the quartz crystallites due to the radionuclides inside the brick�148146 #12;measure the absorbed dose in the bricks agreed within 15%. ...

This paper reviews in some detail personnel exposure rates which will be encountered when the time comes for the decommissioning of the Superconducting Super Collider beam dump absorbers. Discussed are estimates for the total radioactivity content of the graphite core and for residual absorbed dose ...

This monograph covers, in condensed form, the essentials of radiation dosimetry as it is applicable to radiation hardness testing of electronics. An overview of general dosimetry concepts treats absorbed dose and dose rate, charged particle equilibrium, a...

This paper uses biophysical-microdosimetric quantities, measured in a physical surrogate or phantom cell, to explain the shape of absorbed dose-quantal cell response curves, the role of radiation quality and the influence of dose rate. Responses expected ...

This paper uses biophysical-microdosimetric quantities, measured in a physical surrogate or phantom cell, to explain the shape of absorbed dose-quantal cell response curves, the role of radiation quality and the influence of dose rate. Responses expected are explored first in simple autonomous cell systems, ...

The comparison of the NPL and PTB primary Standards was carried out by each laboratory using its standard to measure the absorbed dose rates from a number of NPL secondary standard sources of the radionuclides strontium + yttrium-90 (Sr + Y - 90), thallium-204 (T1-204) and promethium-147 (Pm-147).

This article describes major studies performed by the Chernobyl Center's International Radioecology Laboratory (Slavutich, Ukraine) on radioecology of murine rodents and shrews inhabiting the Chernobyl Exclusion Zone. The article addresses the long-term (1986-2005) and seasonal dynamics of radioactive contamination of animals and reviews interspecies differences in radionuclide accumulations and ...

Models for estimating the absorbed dose due to an atmospheric release of radionuclides are required for the siting of, operations of, and emergency planning for nuclear facilities. In the early days of nuclear power reactors, emphasis was on the long-term dose from routine release. Currently there is interest in models to estimate the ...

The radiation absorbed doses from five commercially available hepatobiliary agents-Tc-99m-tagged analogs of IDA (EIDA, PIPIDA, HIDA, PBIDA, DISIDA*) have been calculated from biokinetic data in 41 normal subjects. Serial gamma images, with blood and urine samples, were obtained to calculate cumulated radioactivity in the source organs: blood, kidey, ...

The radiation absorbed doses from five commercially available hepatobiliary agents--/sup 99m/Tc-tagged analogs of IDA (EIDA, PIPIDA, HIDA, PBIDA, DISIDA) have been calculated from biokinetic data in 41 normal subjects. Serial gamma images, with blood and urine samples, were obtained to calculate cumulated radioactivity in the source organs: blood, kidney, ...

Methods are presented for the calculation of dose-rate conversion factors for external exposure to photon and electron radiation from radioactive decay. A dose-rate conversion factor is defined as the dose-equivalent rate per unit radionuclide concentration. Exposure modes considered are immersion in contaminated ...

A monoenergetic neutron beam simulation study is carried out to determine the optimal neutron energy range for treatment of rheumatoid arthritis using radiation synovectomy. The goal of the treatment is the ablation of diseased synovial membranes in joints, such as knees and fingers. This study focuses on human knee joints. Two figures-of-merit are used to measure the neutron beam quality, the ...

A monoenergetic neutron beam simulation study was carried out to determine the optimal neutron energy range for treatment of rheumatoid arthritis using radiation synovectomy. The goal of the treatment is the ablation of diseased synovial membranes in joints such as knees and fingers. This study focuses on human knee joints. Two figures of merit are used to measure the neutron beam quality, the ...

The influence of cumulative absorbed dose, initial dose rate and mass of the remnant thyroid tissue on outcome of radioiodine treatment was assessed to determine an optimum value of absorbed dose and initial dose rate predictive of ...

The body distribution of Polonium-210 in three fishes from the Sepetiba Bay (Macrodon ancylodon, Micropogonias furnieri and Mugil curema) has been studied under the approach of the Department of Energy of the United States of America (DOE) that set the limit of absorbed dose rate in biota equal to 3.5x10{sup 3} {mu}Gy/y, and that also ...

The body distribution of Polonium-210 in three fishes from the Sepetiba Bay (Macrodon ancylodon, Micropogonias furnieri and Mugil curema) has been studied under the approach of the Department of Energy of the United States of America (DOE) that set the limit of absorbed dose rate in biota equal to 3.5�103 ?Gy/y, and that also ...

The dosimetric properties of polyacrylamide (PAM) were investigated. It was found that this dosimeter is energyindependent from 280 kvp to 35 Mev; is dose-rate-independent between 6 and 150 rads/min; and has a sensitivity of 6 per cent decrease in viscosity per 100 rads. It is antici-pated that this dosimeter will be a valuable supplement to those presently being ...

Polyvinyl chloride (PVC) film dyed with malachite green was studied for high-dose radiation dosimetry using visible spectrophotometry. A linear relationship between the relative absorbance and the absorbed dose at the wavelength 628 nm in the range of 0 125 kGy was found. The effect of dose ...

Methods for determining flux depression into the surface of an absorber and the self-shielding within an absorber are presented. An equation is given for evaluating dose rates from coolant actlvation is pressurized water reactors. A fast neutron dose attenuation kernel for a point ...

A theory was developed to predict the average gamma absorbed dose rates due to a continuous Gaussian plume that meanders due to variations in the wind's direction caused by large-scale eddies. Such meandering often occurs under very stable, low-wind conditions. The theory is based on Gifford's fluctuating Gaussian plume model. ...

A theory was developed to predict the average gamma absorbed dose rates due to a continuous Gaussian plume that meanders due to variations in the wind's direction caused by large-scale eddies. Such meandering often occurs under very stable, low-wind conditions. The theory is based on Gifford's fluctuating Gaussian ...

Free-field power density has long been used as an index of energy dosing in studies of biological effects of microwave radiation. However, this method of quantifying dose can lead to considerable error if it is used as an index of the rate of energy actually being absorbed by a s...

Direct measurements of energy locally absorbed in irradiated materials can be made with adiabatic calorimeters of suitable design. Design criteria imposed by requirements of accuracy include limitations on size and complexity. Small calorimeters of simple design with precision better than 1% at dose rates above 1 rad/sec were ...

Exact two-dimensional and asymptotic one-dimensional integral solutions were obtained for the external dose rate value due to a Gaussian plume. The relative error of the asymptotic solution was found to be less than 5% for downwind distances of 1 to 300 mean free path lengths and for crosswind distances of 0 to 40 mean free path lengths. A good agreement ...

The high dose-rate (HDR) brachytherapy in Cuba is based on soviet made devices type AGAT-V. In order to calibration one of these for clinical use a method based of the different measurement of absorbed dose at the reference point B in a paraffin phantom w...

Calculations have been carried out to estimate the absorbed-dose and dose-equivalent rates at various depths in the atmosphere produced by an energetic solar flare - the flare of February 23, 1956. The dose rates are determined both by computing flux spec...

The absorbed dose primary standard of the BEV is a graphite calorimeter. Two methods are employed for the conversion of absorbed dose to graphite into absorbed dose to water: calculation on the one hand and the use of an ionization chamber in combination ...

In Health Physics Division annual progress report for period ending July 31, 1973. Estimates were made of the radiation dose rate and dose absorbed by various human organs and tissues as a function of age from six radionuclide photon sources ranging from 20 keV to 2 Mev distributed uniformly in the body. ...

The purpose of this study is to measure the environmental radiation exposure in and surrounding the room of patients treated with (131)I. Absorbed dose rates were measured using thermoluminescence dosemeters, type TLD-200 (CaF(2):Dy), in a continuous monitoring programme. It is found that the estimated annual shallow and deep ...

Absorbed dose and dose equivalent from negatively and positively charged pions in energy range 10 to

... Title : A FORTRAN PROGRAM TO DETERMINE ABSORBED ORGAN DOSE DUE TO INHALATION OF RADIONUCLIDES,. ...

In internal emitter therapy, an accurate description of the absorbed dose distribution is necessary to establish an administered dose-response relationship, as well as to avoid critical organ toxicity. This work describes the implementation of a dosimetry method that accounts for the radionuclide decay spectrum, and patient-specific ...

Determining the dose rate as a function of distance within both cancerous tumor tissue as well as healthy tissue represents a proof of concept for medical diagnostic techniques finding overall dose absorption. The Monte Carlo N-Particle Transport Code (MCNPX) was used to replicate radiotherapy treatments of external-beam radiation and ...

The relationship between the radiation absorbed dose and the NMR longitudinal and transversal relaxation rates, R1 and R2, respectively, of a ceric sulphate dosimeter was examined. By adding copper sulphate, the R1 and R2 dose-responses were found to be linear up to 60 kGy with dose ...

... of absorbed dose; rem relates the absorbed dose in human tissue to the ... effort to increase the nation's preparedness for potential attacks against ...

... Title : Computational Determination of Absorbed Dose Distributions From Multiple Volumetric Gamma Ray Sources,. Corporate Author : ...

Current methods for calculating the absorbed dose in a target region from a source region rely on a standard {open_quotes}reference man{close_quotes} geometry and assume an uniform distribution of radiolabel. While this approach is acceptable at the low levels of radioisotope administered for most diagnostic purposes, the generality of the calculations is ...

Here, an anatomic model of mullet is developed on sampling, dissection, and measurement on site. A Monte Carlo code is used to compute the energy-absorbed fraction in tissues and organs of the mullet, and dose rates are calculated. Some previous methods are selected for comparison. The results calculated by means of a newly developed ...

Accurate calculation of absorbed dose to target tumors and normal tissues in the body is an important requirement for establishing fundamental dose-response relationships for radioimmunotherapy. Two major obstacles have been the difficulty in obtaining an accurate patient-specific 3-D activity map in-vivo and calculating the resulting ...

An irradiation experiment on insulation gas was carried out to evaluate ionization current and voltage holding characteristics with the gamma-rays from Co-60. The gases of air, SF{sub 6}, C{sub 2}F{sub 6}, CO{sub 2}, and mixture of air and SF{sub 6} were investigated using parallel-disk electrodes all the absorbed dose rate of up to ...

The results of chromosome aberration analyses in 68 Thorotrast patients are discussed. In all patients dicentric chromosome aberrations were found but the chromosome aberration rate neither corresponds with the calculated whole body activity or the estimated absorbed dose in the organs of the RHS nor with the radium-224-equivalent ...

This report is a summary of experimental results on radiolytic hydrogen yields from tetraphenylborate (TPB) slurries related to the In-Tank Precipitation (ITP) process. The yields are presented as ''G values'' in units of molecules per 100 eV of absorbed energy. If the radiolytic dose rate is known, ...

The absorbed gamma-dose rate in air at a height of 1 m above ground level was calculated from activity concentrations of gamma-emitting radionuclides in arable soil samples collected from eight locations within Sinnar State using the published Dose Rate Conversion Factors. Measurements were ...

Radiochromic Dye Dosimeters (Gafchromic DM-100) were used to measure the absorbed doses in liquid samples exposed to a {sup 137}Cs gamma-ray source. The initial calibration of commercially available radiochromic film was performed using a {sup 60}Co gamma-ray source. When exposed to gamma-ray doses of 0.5 to 200 kGy, a color change ...

The concept of a dose-rate conversion factor for external exposure to photons and electrons and its application to the estimation of population dose following routine or accidental releases of radionuclides to the atmosphere were discussed. Dose-rate conversion factors are useful for exposure situations in which the radionuclide ...

The Phantom Torso Experiment (PTE) was flown on the International Space Station (ISS) during Increment 2 (April-August 2001). The experiment was located in the US Lab module Human Research Facility (HRF) rack. The objective of the passive dosimetry portion of the experiment was to measure spatial distributions of absorbed dose in the 34, 1 inch sections of ...

Absorbed-dose and dose-equivalent rates for astronauts were estimated by multiplying fluence-to-dose conversion coefficients in the units of Gy.cm(2) and Sv.cm(2), respectively, and cosmic-ray fluxes around spacecrafts in the unit of cm(-2) s(-1). The dose conversion coefficients employed in ...

The concepts of radiation exposure dose, absorbed dose, and biological dose resulting from ionizing particles are reviewed. The units used in radiation measurements are defined, and the concept of electronic equilibrium is discussed. The Bragg-Gray cavity relation ls used to calculate the ...

The micronucleus assay in human peripheral blood lymphocytes is a sensitive indicator of radiation damage and could serve as a biological dosimeter in evaluating suspected overexposure to ionising radiation. Micronucleus (MN) frequency as a measure of chromosomal damage has also extensively been employed to quantify the effects of radiation dose rate on ...

The radiation-induced UV-vis spectrum of /?-terthiophene radical cation in solid is reported. The radical cation initiates an oligomerization in the CTA matrix producing permanently coloured conjugated polarons. The specific net absorbance at 465nm is linearly related with dose up to 2�106Gy, for electrons and gamma irradiation. The decrease of the UV ...

Luminescence excited by a small X-ray generator (Varian VF-50J) instead of the usual 90Sr 90Y beta source was measured following optical stimulation. The optimal X-ray irradiation conditions have been assessed, including the irradiation dose rate and the thickness of Al-absorber, in the equivalent dose ...

The dosimetry parameters of the IRH10 (192)Ir high dose rate brachytherapy source were obtained from the dose calculation formalism recommended in the AAPM Task Group No. 43 report using the Monte Carlo code PENELOPE. The absorbed doses to water and air originating from the photons of the IRH10 ...

The construction and operation details of a local absorbed dose microcalorimeter are presented. This calorimeter measures the absorbed dose rate at any desired point within an irradiated medium. The measurement is specific to a sufficiently limited region (2.0 cm in dia, 0.3 cm deep) ...

External gamma irradiation of dogs with doses of 103.2 and 51.6 mC/kg combined with the effect of inhaled plutonium-239 accelerates the formation of absorbed doses in secondary organs of the radionuclide deposition by 41.7 and 2.4 times, respectively, whereas the dose of 25.8 mC/kg is ineffective. As estimated by ...

Absorbed dose rate measurements of a 50 kV(p) handheld X-ray probe source in a water phantom are described. The X-ray generator is capable of currents of up to 40 microA, and is designed for cranial brachytherapy and intraoperative applications with applicators. The measurements were performed in a computer-controlled water phantom in ...

This paper presents two methods for absorbed dose determination with ionization chambers at short distance from 60Co and 192Ir brachytherapy sources. The methods are modifications of the Bragg-Gray and large cavity principles given in the IAEA code of practice for high- and medium-energy photon beams. A non-uniformity correction factor to account for the ...

The effect of irradiation temperature and absorbed dose on cross-linking and destruction of butadiene-nitrile (BDN) and fluoro rubbers and their vulcanizates in the nondeformed and strained state was studied. Irradiation of BDN and its vulcanizates with low absorbed doses caused a simultaneous rupture of ...

A beam position detector for measuring the properties of a charged particle beam, including the beam's position, size, shape, and intensity. One or more absorbers are constructed of thermo-resistive material and positioned to intercept and absorb a portion of the incoming beam power, thereby causing local heating of each ...

Phantom-based and patient-specific imaging-based dosimetry methodologies have traditionally yielded mean organ-absorbed doses or spatial dose distributions over tumors and normal organs. In this work, radiobiologic modeling is introduced to convert the spatial distribution of absorbed dose into ...

A survey of the geochemical literature and unpublished data has resulted in the classification of the concentrations of the naturally occurring radioelements U, Th, and K by their associated rock types. A data base of over 2500 entries has been compiled, permitting calculation of terrestrial gamma-ray absorbed dose rates. The general ...

A survey of the geochemical literature and unpublished data has resulted in the classification of the concentrations of the naturally occurring radioelements U, Th, and K by their associated rock types. A data base of over 2500 entries has been compiled, permitting calculation of terrestrial gamma-ray absorbed dose rates. The general ...

A set of four tissue-equivalent proportional counters (TEPCs), with their detector heads at the centers of 0 (bare), 3, 7 and 9-inch-diameter aluminum spheres, were flown on Shuttle flight STS-89. Five such detectors at the centers of polyethylene spheres were flown 1 year earlier on STS-81. The results of dose-depth dependence for the two materials convincingly show the ...

An isothermal calorimetric method for the measurement of the energy dose absorbed during reactor irradiatrons of substances is described. The dose values are calculated with respect to the geometrical arrangement from the resulting irradiation temperatures with an absolute error of about 20%, and a relative one of a few ...