bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Few Remarks on Dose Equivalent and Quality Factor
Authors: Sabol J. 
Published: February 2017

Abstract
The concept of the most important radiation protection quantity, dose equivalent, together with its unit is discussed. It has been concluded that this quantity cannot be considered to be a pure physical quantity, but rather a biophysical quantity. The idea is supported by an analogy between radiation protection and photometry where there exist physical quantities alongside photometry quantities based on the response of the eye to light. In order to avoid the persistent confusion regarding the unit of the dose equivalent, it is suggested that dimensions be assigned to the quality factor. As long as the quality factor is assumed to be a conversion factor between the physical and the radiation protection quantity, its dimension must be equal to the quotient of the units of the dose equivalent and the absorbed dose; i.e. the quality factor should be given in Sv.Gy-1.
Lyoluminescence in Neutron Therapy
Authors: Haverkamp U. , Wiezorek C. , Pötter R. 
Published: February 2017

Abstract
Lyoluminescence (LL) is based upon light emission during dissolution of previously irradiated inorganic or organic materials. For the dosimetry of fast neutrons in particular the advantage of lyoluminescence for radiological purposes lies in the use of certain organic materials whose hydrogen content is similar to that of tissue. Mannitol, trehalose, glucose and leucine were used as dosimetric materials and were irradiated with fast neutrons (d,T 14 MeV) over a therapeutic dose range (0.5-7.0 Gy). The integral light output is a measure of the absorbed dose. The materials, irradiated with 5 Gy, show differences in the absolute light output and the light output relative to 60Co gamma rays. In order to apply lyoluminescence dosimetry in the clinical context in neutron therapy, a suitable method for basic and in vivo dosimetry was developed and verified comparing the results with TE ionisation chamber dosimetry.
Radon Classification of Building Ground
Authors: Slunga E. 
Published: February 2017

Abstract
The Laboratories of Building Technology and Soil Mechanics and Foundation Engineering at the Helsinki University of Technology in cooperation with The Ministry of the Environment have proposed a radon classification for building ground. The proposed classification is based on the radon concentration in soil pores and on the permeability of the foundation soil. The classification includes four radon classes: negligible, normal, high and very high. Depending on the radon class the radon-technical solution for structures is chosen. It is proposed that the classification be done in general terms in connection with the site investigations for the planning of land use and in more detail in connection with the site investigations for an individual house.
226Ra and 228Ac in a Freshwater Ecosystem
Authors: Carreiro M.C.V. , Sequeira M.M.A. 
Published: February 2017

Abstract
Uranium, thorium, and their decay products, being primordial radionuclides, are of interest in the nuclear fuel cycle. They have therefore been systematically considered in the radiological survey of the Portuguese rivers Douro and Tejo. We summarise survey data on 226Ra and 228Ac concentrations, in water, sediments, fish and acquatic macrophytes, determined by gamma spectrometry, and covering the period from 1976 to 1981 for the River Douro and 1976 to 1986 for the River Tejo. Field concentration factors (CF) and distribution coefficients (Kd) determined for these rivers have values within the following ranges: CF values in fish muscle, 49 to 52 for 226Ra and 41 to 49 for 228Ra; in aquatic macrophytes (1 to 1.5) x 103 for 226Ra and (0.75 to 1.1) x 103 for 228Ra; values of Kd in sediments (2.5 x 3.3) x 103 for 226Ra and (2.9 to 3.2) x 103 for 228Ra. These values are discussed. 228Ac/226Ra ratios for both rivers are compared and interpreted.
Natural Radioactivity in Portuguese Mineral Waters
Authors: de Bettencourt A.O. , Teixeira M.M.G.R. , Faisca M.C. , Vieira I.A. , Ferrador G.C. 
Published: February 2017

Abstract
Concentration levels of 226Ra, 210Pb and 222Rn have been analysed in most of the bottled waters commercially available in Portugal, as well as in some spring waters. Concentrations up to abut 2 Bq.l-1, with a geometric mean of 27 mBq.l-1 were observed for 226Ra. For 210Pb a geometric mean of 18 mBq.l-1 with values ranging from 2 to 392 mBq.l-1 and for 222Rn a geometric mean of 17 Bq.l-1 with values ranging from &lt;1 to 814 Bq.l-1 were measured. These values are compared with concentrations reported for other countries. Doses resulting from the consumption of these waters were calculated. The effective dose equivalents due to the intake of 226Ra and 210Pb present in these waters are expected to range from about 5 x 10-3 to 0.2 mSv.y-1. Dose equivalents to the stomach due to 222Rn intake through water consumption are estimated to reach values around 20 mSv.y-1.
Laser-Induced Damage of DNA
Authors: Schulte-Frohlinde D. 
Published: February 2017

Abstract
Laser excitation of DNA in aqueous solution leads to biphotonic formation of base radical cations and solvated electrons in addition to monophotonic products. The chemical pathways from the radical cations to strand breakage for several polynucleotides and single-stranded DNA are reviewed. An important feature of the mechanism is that the base radical cations are converted into neutral radicals prior to H abstraction from the sugar at pH 7. The neutral base radicals lead to single-strand break formation with the same yield as that obtained from the radical generated from the bases by reaction with OH. From this it can be inferred that, as far as ionisation by high energy irradiation is concerned, similar radicals are produced in DNA by direct ionisation as by reaction with OH radicals.
Variance-Covariance Measurements of yD for 15 MeV Neutrons in a Wide Range of Site Sizes
Authors: Goldhagen P. , Randers-Pehrson G. , Marino S.A. , Kliauga P. 
Published: February 2017

Abstract
Using the variance-covariance method and a pair of wall-less spherical ionisation chambers, we have measured the dose mean lineal energy, yD, for 15 MeV neutrons in nine site diameters ranging from 4.7 µm down to 19 nm (mean chord lengths from 3.15 µm to 13 nm). The neutrons were produced at the RARAF Van de Graaff accelerator using the T(d,n)4He reaction. Several practical improvements in the variance-covariance technique were developed, including subtraction of the variance of the noise current from the total variance and elimination from the data of electronic pulses produced when neutrons interacted directly in the integrated circuit chips of electrometers. At site diameters of 0.3 µm and above, conventional pulse height microdosimetry was also performed, using the same detectors operated as proportional counters. Values of yD measured by the two different methods are in excellent agreement.
Microdosimetric Measurements on the Clatterbridge Neutron Cancer Therapy Cyclotron
Authors: Taylor G.C. , Scott M.C. , Fletcher J.G. 
Published: February 2017

Abstract
Microdosimetric spectra have been measured both in air and in phantom for the Clatterbridge p(62)Be neutron cancer therapy cyclotron, Merseyside, UK. The measurements were carried out using a half-inch single-wire counter from Far West Technology, USA, for a simulated diameter of 2 µm. Because the measurements were made over several visits a rigorous calibration regime was used to ensure good agreement between spectra measured at different times. This was achieved by using the a particle edge on the y.D(y) spectra, the lineal energy of which was assumed to be 372 keV.µm-1. Measurements made at fixed positions in phantom show an increase in the height of the proton edge with increasing field sizes. Measurements made with fixed field sizes show a shifting of the proton peak to lower lineal energies with increasing depth into the water phantom, indicating a hardening of the neutron spectrum. This is consistent with spectrometric measurements made at Clatterbridge and reported elsewhere.
A Microdosimetric Comparison of High Energy Neutron Therapy Facilities: Clatterbridge and M.D. Anderson
Authors: Kliauga P. , Bonnett D. , Waker A. 
Published: February 2017

Abstract
Radiation quality of fast neutron beams used for radiation therapy can change with depth, the primary effect being a 'hardening' of the neutron beam produced by the scattering of slow neutron components. We report measurements of microdosimetric spectra in phantom, with and without hardening filter, for the 62 MeV p®Be [p(62)+Be] machine at the MRC Cyclotron Unit at Clatterbridge Hospital. Comparison is made with similar measurements on the 42 MeV beam [p(42)+Be] at M.D. Anderson Hospital. An interesting observation is the comparison of results obtained with differing counters and phantoms, which demonstrate that these parameters can have a non-negligible effect on intercomparisons between machines.
Kinetic Analysis of Natural and Beta-Induced TL in Albite
Authors: Kirsh Y. , Kristianpoller N. , Shoval S. 
Published: February 2017

Abstract
Kinetic parameters are evaluated for the thermoluminescence (TL) of geological samples of the feldspar albite (NaAlSi3O8). Both natural and laboratory -induced TL curves are studied between RT and 500 oC. The natural TL shows an intense peak at about 340 oC while the lab-induced glow curve consists of a peak near 200 oC, with a long high temperature tail. The kinetic analysis of the two glow curves shows that both can be described in terms of the same series of discrete traps, with the activation energies: 0.64, 0.71, 0.93, 1.08, 1.25, 1.64 and 1.85 eV. The intensities of the low temperature peaks in the natural TL were found to be rather high in view of the half-lives of the relevant traps. This might be due to tunnelling of charge carriers from deeper traps. This should be taken into consideration when samples of albite are used for geological and archaeological dating or in accident dosimetry.
Luminescence and Dosimetric Performances of KMgF3 Crystals Doped with Metal Impurity Ions
Authors: Furetta C. , Bacci C. , Rispoli B. , Sanipoli C. , Scacco A. 
Published: February 2017

Abstract
Thermoluminescence spectra have been recorded for crystals of pure KMgF3, KMgF3:Pb2+ and KMgF3:Eu3+, with the aim of identifying new phosphors for radiation dosimetry. Glow peaks, due to thermal activation of colour centres formed by ß or ? irradiation, were measured in both pure and doped materials. Typical thermoluminescence signals due to Pb2+ or Eu3+ impurities have been obtained, besides those of the host KMgF3. The intensity of the thermoluminescence peaks is not very high in Pb2+-doped samples, while Eu3+ ions are found to be excellent activators, as usual for rare earth impurities. In KMgF3:Eu3+ a new prominent peak has been found very efficient for monitoring radiation doses, because of its high sensitivity, good stability over time and elevated activation energy.
Characterisation of N-Acetyl-D-Glucosamine (NAG) as a Lyoluminescent Dosemeter
Authors: Azorin J. , Gutiérrez A. 
Published: February 2017

Abstract
Lyoluminescent properties of N-acetyl-D-glucosamine (NAG) were investigated for their suitability as a dosemeter in a lyoluminescent system using sensitised solutions as solvents. Temperature and pH of the solvents were also varied. The detection limit for the system NAG-luminol at 20 oC using a solvent pH value of 10.6 was of the order of 3 mGy. The reproducibility was within ± 5% for doses of the order of 1 Gy. Measurements with isoluminol showed slightly higher amplification of the LL signal than that obtained with luminol.
A New TL Detector Developed for Multiple Applications
Authors: Wang S. , Wang Y. , Cai G. , Wang S. , Zha Z. 
Published: February 2017

Abstract
A new TL detector was prepared by doping PbO as the fourth dopant into LiF(Mg,Cu,P). The 'anomalous photon energy response' of the detector was eliminated; this detector can meet the various energy response requirements of measuring the individual and ambient dose equivalent (Hp(10) and H*(10)) and others. The range of perfect linearity is at least 200 nGy - 12 Gy without supralinearity. The detection threshold is 107 Gy with flowing N2 gas, and it has an ideal glow curve shape with the dominant peak at 210 oC. Both the photosensitivity and thermal fading effects are the same as that of LiF(Mg,Cu,P) which is insensitive to many chemical solutions. Being of small size, it can be used to measure the radiation dose in vitro or in vivo, where this is possible.
ESR Dosimetry with Magnesium Sulphate
Authors: Morton J.R. , Ahlers F.J. , Schneider C.C.J. 
Published: February 2017

Abstract
The aim of the investigation is to enhance the ESR dosemeter sensitivity in the therapy dose range below 10 Gy, where the ESR spectrum of the a-alanine radical becomes increasingly difficult to evaluate for dosimetry. Anhydrous magnesium sulphate, MgSO4, appears to be an excellent candidate from the spectrometric point of view. On irradiation with 60Co ? rays the stable radical SO3 is produced whose ESR signal amplitude increases linearly with dose up to about 105 Gy. Ignoring the abundant isotopes 17O (0.04%) and 33S (0.74%), the spectrum of SO3 is a single line at g = 2.0036 of width 0.5 mT which is stable at temperatures up to at least 120 oC. Using the conventional peak-to-peak method of dosemeter readout, the MgSO4 dosemeter is somewhat more sensitive than the traditional alanine dosemeter of the same mass. Its main advantage over the alanine dosemeter is, however, the ease of computer enhancement and the possibility of integration which the single-line spectrum offers.
First Experience with Pattern Approvals of Dosimetry Systems in Germany
Authors: Ambrosi P. , Neuhaus R. , Piesch E. 
Published: February 2017

Abstract
In the Federal Republic of Germany type tests (pattern approvals) of dosimetry systems for individual monitoring are mandatory. For dosimetry systems with TL or PL detectors the relevant requirements are stated in PTB-A 23.2. These requirements are explained and the experience obtained in the course of the type test of a Toshiba Glass dosimetry system, together with some of the results of the pattern approval, are given.
An Intercomparison of Glow Curve Analysis Computer Programs: I. Synthetic Glow Curves
Authors: Bos A.J.J. , Piters T.M. , Gómez-Ros J.M. , Delgado A. 
Published: February 2017

Abstract
Thirteen different computer programs for glow curve analysis are compared. Eleven programmes used a shape of the glow peak based on the Randall-Wilkins model, but a variety of different approximations for evaluating the peak shape was noticed. Twelve programmes were able to reproduce the peak areas and activation energies of a synthetic glow curve according to the Randall-Wilkins model simulating a four peaks TLD-100 glow curve within 6.3%. Four programmes of those twelve were able to reproduce the input values within 0.4%. Clear differences in performance between the programmes are due to differences in approximations used in calculating the glow peak shape.
Variance-Covariance Measurements in Therapeutic and Diagnostic Radiation Beams
Authors: Honoré H.B. , Jensen L.C. , Jessen K.A. , Nielsen H.H. 
Published: February 2017

Abstract
Cylindrical tissue-equivalent twin ionisation chambers have been developed based on experience with proportional counters for application in microdosimetric variance-covariance measurements of the dose mean lineal energy, yD, in therapeutic and diagnostic radiation beam qualities. It is concluded that the method is applicable but the size of the detector signals has to be optimised very carefully in respect to noise reduction and the total relative variance. It is proposed that results from the proportional mode and the ionisation mode are compared to obtain variance. It is proposed that results from the proportional mode and the ionisation mode are compared to obtain reliable values for the microdosimetric beam quality characterisation necessary to assess clinically relevant differences.
The Efficacy and Durability of Radon Remedial Measures
Authors: Cliff K.D. , Naismith S.P. , Scivyer C. , Stephen R. 
Published: February 2017

Abstract
In the UK, over 16,000 homes, from an estimated 100,000, with annual average radon concentrations exceeding the UK Action Level of 200 Bq.m-3 have been discovered. Some 600 householders who have taken action have sought confirmatory measurements from NRPB. Results for 345 such homes are discussed. A number of remedied homes are being remeasured annually to determine the durability of the remedies: results for the first year follow-up measurements are given. In a separate exercise, homes having the highest radon levels known in the UK have been enrolled in a research programme of the Building Research Establishment. The results for 53 homes in which BREW surveyed, designed and supervised remedial work are presented.
Cocarcinogenic Effect of Cytochrome P-450 1A1 Inducers for Epidermoid Lung Tumour Induction in Rats Previously Exposed to Radon
Authors: Douriez E. , Kermanac'h P. , Fritsch P. , Bisson M. , Morlier J.P. , Monchaux G. , Morin M. , Laurent P. 
Published: February 2017

Abstract
The aim of this work was to characterise the cocarcinogenic effect of CYP1A1 inducers in male Sprague-Dawley rats previously exposed to 1000 WLM radon. Three inducers were used: methylcholanthrene (MC), metabolised by CYP1A1 into strong mutagenic compounds; 5,6-benzoflavone (ßNF) metabolised into non-mutagenic compounds; and 2,3,7,8 tetrachlorobenzo-p-dioxin (TCDD) regarded as non-mutagenic and non-metabolised. These inducers were administered by six repeated intramuscular injections of 25, 25 and 0.0013 mg per kg respectively at 2-week intervals. Rats were studied 1 or 4 months after the end of the treatments. A cocarcinogenic effect was observed for each compound corresponding to specific occurrences of squamous cell carcinoma. Latency periods for about 100% tumour induction were about 100 days for MC and ßNF but increased to 200 days for TCDD. Biochemical studies have shown a similar global CYP1A1 induction for each treatment corresponding to about 40 times the control value. Immunohistolocalisation of CYP1A1 was confined to some bronchial cells in controls whereas it was clearly demonstrated after each chemical treatment in hyperplastic epithelial foci.
Stabilisation Characteristics of Ventilation in Buildings
Authors: Peter J.E. , Haider B. , Ferron G.A. 
Published: February 2017

Abstract
Indoor radon concentrations depend strongly on ventilation between the rooms and the atmosphere. Here a set of linear differential equations is used to describe this transport. The solution for a multi-room building is calculated numerically. A house with three storeys and three by three rooms on each storey was chosen to achieve some generality. The air in each room is open to exchange with the air in adjacent rooms. All rooms except the middle rooms ventilate with the atmosphere. The middle rooms represent a staircase and ventilate with all adjacent rooms. The calculations were made for radon sources in one, some and all rooms, and different winds. Special emphasis was laid on the description of stabilisation times. Each room in between the source and the room under consideration in the multi-room model reduces the maximum concentration by a factor of about 2.6 and delays the stabilisation by factor of about 1.7.
False Positive and False Negative Radon Measurement Results Due to Uncertainties in Seasonal Correction Factors
Authors: Cliff K.D. , Miles J.C.H. , Naismith S.P. 
Published: February 2017

Abstract
Data from the UK national survey of radon in 2300 homes has been re-analysed to determine the uncertainty in seasonal correction factors applied to measurements of less than l year. The required correction factor for each six-month result was calculated from the known annual average for the appropriate home. The seasonal correction factors derived for each month were found to be approximately log-normally distributed, with an average geometric standard deviation of 1.36. Following this initial survey, radon measurements have been made in more than 80,000 homes in southwest England to determine whether they are above the UK radon Action level of 200 Bq.m-3. The measurements were carried out over three months in each case using etched track detectors in two locations in each home, and the results were corrected for the average seasonal variation found in the original UK study of radon in homes. Because of the uncertainty in the seasonal correction factors, households with between 130 and 300 Bq.m-3 were advised to have a second three-month measurement in a different season before deciding whether or not to take remedial action. More than 7000 homes were remonitored for this purpose. The results are analysed to show the number of false positive and false negative results that would have been reported if advice had been based solely on the initial measurement. It is shown that the present scheme results in extremely small numbers of false positive and false negative results.
Microcomputer Controlled Reader Systems for Archaeological and Geological TL Dating
Authors: Bøtter-Jensen L. , Medjahl V. 
Published: February 2017

Abstract
Two fully automated TL reader systems for TL dating and a manually operated reader for research purposes were put into operation during 1982-83. All systems are controlled by HP-85 or HP-86 microcomputers; thus flexibility in selection of measurement parameters, calculation of TL signals and display and printout of glow curves is achieved. The basic design of the automated reader system incorporated a 24-position microprocessor-controlled sample changer and a beta irradiator. The system automatically provides the data for constructing the primary and secondary response curves required for determining the archaeological and geological ages. The principle of the measurement procedures are described, and dating results are presented to illustrate the performance of the systems.
New Experimental Data on the Sensitivity to Fast Neutrons of a Number of Sintered Commercial TL Phosphors
Authors: Scarpa G. 
Published: February 2017

Abstract
The paper reports the results of an experimental investigation carried out during the last 3 years, on the neutron sensitivity of TL phosphors. 13 different types of solid TL detectors (chips, ribbons and discs) of commercial grade were included in the experiment. The irradiations were performed using narrow spectra of fast neutrons in the range 0.6-15 MeV, and wide spectra from a thick beryllium target (mean energy 7.5 MeV) and from a 252Cf source, with accurately known neutron and gamma components. The results in free air are in fairly good agreement with the data available in the literature. The sensitivity coefficient, kU, of 6LiF and of boron based dosemeters at the surface and inside a water phantom are much higher than in free air, as expected from thermalising properties of water. A further increase was obtained when the detectors were exposed in a tissue-equivalent container. The results indicate that the neutron-gamma discrimination by the classical twin-detectors technique could be based upon the use of 6LiF, lithium borate or, perhaps, magnesium tetraborate, as neutron-sensitive phosphors, and of 7LiF or calcium based TLDs as neutron insensitive dosemeters.