The radioactive gas measuring device comprises an introducing means for introducing radioactive gas, a sampling vessel, a measuring device for introducing and measuring radioactive gas, a gas bag for storing the radioactive gas after the measurement, an exhaustion device for exhausting the inside of the gas bag and containing the exhausted gas in a tank and a sensor for operating the exhaustion device upon reaching a predetermined value. The radioactive gas is stored in a gas bag after the measurement, and the pressure of the radioactive gas is kept stable, to improve the accuracy of the measurement. Further, when the amount of the stored radioactive gas is increased after the measurement, and the volume of the gas bag reaches a predetermined value, since the exhaustion device is operated by the sensor, the operation of the measuring device can be simplified. Then, the measurement for the radioactive gas can be conducted stably at high accuracy, thereby enabling to measure an absolute value of the impurity. The measurement for the impurity of the radioactive gas can be remarkably facilitated in the site of medical therapy. (N.H.).

A method of evaluation of proportional counter gas gain from arbitrary current measurements has been developed. It provides absolute value of the gain in range from 1 to 10**8 with moderate current sensitivity and without knowledge of used radioactive source properties. As an example we present dependence of the gain versus voltage for drift lubes of ATLAS Muon Spectrometer filled with mixtures Ar-CO//2(93-7) and Ar-N//2-CH//4(91-4-5) at 3 bar absolute pressure. Results are compared with the gain obtained from ADC measurements. 7 Refs.

Two accidents happened in September 1999 (meteorite dropping accident and JCO criticality accident) are linked to each other at a common point concerning radioactivity, and chemists specialized in radioactivity have been executing active researches. In this paper, a focus of discussion is put on the measurement of radioactivity induced by neutrons due to cosmic rays or criticality. Researches executed actively by the chemists during several weeks for calculating neutron fluxes around the spot of the criticality accident and estimating the meteorite matrix on the basis of nuclear reaction in outer space under absolute time restriction of radioactive half life. In the meteorite dropping falling accident, a stone fell through the roof of the second floor of a private house in Kobe, and this stone was proved to be a meteorite on the basis of a non-destructive {gamma} ray spectrum measurement carried out by the Low Level Radioactivity Experiment Facility of Science Department of Kanazawa University. Detections of Mg-28 with a radioactive half life of 21 hours and Ni-57 with a radioactive half life of 1.45 days were succeeded for the first time in the world owing to an extremely short time from finding information on the internet till carrying out the measurements. (NEDO)

The method covers the measurement of radioactive manganese in water in concentrations above 10/sup -3/ uCi/liter (37 disintegrations/s.liter). It is limited to the manganese radioisotopes of masses 54 and 56. The method may be used for absolute measurements by calibrating the nuclear radiation detector with a standard manganese radioisotope of the same mass, or for relative measurement by comparing the measurements made. The method includes a discussion of interferences, apparatus, reagents, sampling, calibration and standardization, procedure, and calculation. (JMT)

Microscopic beta and gamma data for decay-heat needs are defined as absolute-intensity spectral distributions of beta and gamma rays following radioactive decay of radionuclides created by, or following, the fission process. Four well-known evaluated data files, namely the US ENDF/B-V, the UK UKFPDD-2, the French BDN (for fission products), and the Japanese JNDC Nuclear Data Library, are reviewed. Comments regarding the analyses of experimental data (particularly gamma-ray data) are given; the need for complete beta-ray spectral measurements is emphasized. Suggestions on goals for near-term future experimental measurements are presented. 34 references.

Purpose To analyze the stability, visibility, and histology of a novel implantable soft-tissue marker (nonradioactive and radioactive) implanted in dog prostate and rabbit liver. Methods and Materials A total of 34 nonradioactive and 35 radioactive markers were implanted in 1 dog and 16 rabbits. Stability was assessed by measuring intermarker distance (IMD) variation relative to IMDs at implantation. The IMDs were measured weekly for 4 months in the dog and biweekly for 2-4 weeks in the rabbits. Ultrasound and X-ray imaging were performed on all subjects. Computed tomography and MRI were performed on the dog. Histologic analysis was performed on the rabbits after 2 or 4 months. Results A total of 139 measurements had a mean (+- SD) absolute IMD variation of 1.1 +- 1.1 mm. These IMD variati...

Absolute activity measurements of alpha, beta and gamma emitting radioactive sources are important in numerous fields such as therapeutic radiology and the characterization of nuclear waste. Conventional ionization and liquid scintillation detectors, which are commonly used for these applications, have an energy dependent quantum efficiency and severe limitations in energy resolution. As a novel alternative we have developed a detector based on a metallic magnetic calorimeter (MMC) with a gold absorber that covers the full solid angle of 4? around the radioactive source. Deposition of energy in the absorber causes a temperature rise and results in a change of magnetization of a parametric Au:Er sensor, which can be measured by a low-noise high-bandwidth dc-SQUID. The detector has equal sen...

The determination of potassium in natural silicate minerals by pile neutron activation and by counting the induced beta radiation in the irradiated specimen without chemi cal processing is described. An end-window proportional counter and aluminum absorbers are used for radioactivity measurement. Precision and absolute accuracy of the method are of the order of 1%, and interference by trace elements in general is less than this. Results are presented for the analysis of the standard granite G-1, diabase W-1, argillaceous limestone NBS No. 1a, feldspar NBS No. 70, and biotite M.I.T. No. B3203. (auth)

Detailed measurements have been made with the CMS hadron calorimeter endcaps (HE) in response to beams of muons, electrons, and pions. Readout of HE with custom electronics and hybrid photodiodes (HPDs) shows no change of performance compared to readout with commercial electronics and photomultipliers. When combined with lead-tungstenate crystals, an energy resolution of 8\\% is achieved with 300 GeV/c pions. A laser calibration system is used to set the timing and monitor operation of the complete electronics chain. Data taken with radioactive sources in comparison with test beam pions provides an absolute initial calibration of HE to approximately 4\\% to 5\\%.

A method based on the coupled decay-chain equations for extracting the isotopic and the isomeric composition of a postaccelerated radioactive ion beam is presented and demonstrated on a data set from a Coulomb excitation experiment. This is the first attempt of analyzing the content of a postaccelerated radioactive ion beam using this technique. The beam composition is required for an absolute normalization of the measurement. The strength of the method, as compared to present online-based methods, lies in the determination of the isomeric fraction of a partially isomeric beam using all data accumulated during the experiment. We discuss the limitations and sensitivity of the method with respect to the ?-ray detection efficiency and the accumulated flux.

The activity measurement techniques by liquid scintillation spectroscopy consist to mix the radioactive solution to measure with a scintillating liquid and to transform the ionizing radiations, resulting from decays, into light, detectable and quantifiable. The main advantages of these techniques are the easiness of preparation of the radioactive sources, the geometric efficiency of detection of 4{pi} and the possibility of detection of low-level energy radiations. There are one of the only methods giving the possibility to measure the activity of pure {beta} radionuclides; indeed, the nuclear disintegration is not accompanied of gamma radiations detectable by other techniques. There are one of the only methods too of measurement of radionuclides which disintegrate by electron capture and especially those leading to the emission of low-level energy ionizing radiations. Liquid scintillation spectroscopy can be used as an absolute method of activity measurement that is to say without the use of a calibration standard. The modern liquid scintillation counting devices can be very sensitive; the measurement of micro-activities being possible. Some of the applications of these activity measurement techniques are the carbon 14 dating and the geological tracing. Their main disadvantage is the global energetic yield which is low and variable in terms of the composition of the scintillation source necessitating to calculate the detection yield for each condition of measurement. (O.M.)

The methods cover the determi033068ation of radioactive iodine in water in concentrations greater than 100 pCi/liter. Concentration of the sample can increase the sensitivity of the methods. The methods include heterogeneous exchange, distillation, and extraction. The methods may be used either for absolute measurements by calibrating the nuclear radiation detector with a standard iodine radioisotope of the same atomic mass, or for relative measurements by comparing measurements with each other. The methods are limited by choice of radiation detector and length of analysis to the determination of iodine isotopes of mass 129, 131, 132, 133, 134, and 135 which are fission products. Each method includes a description of application, interferences, reagents, procedure, calculation, and precision. (JMT)

The history of radiocarbon dating from 1939 to the present is reviewed. The basic principles of radiocarbon dating are that cosmic rays make living things radioactive with {sup 14}C to a certain level fixed by the environment and that at death the intake of food stops so no replenishment of the {sup 14}C steadily lost by the immutable decay occurs. Therefore measurement of the degree of decay gives the time lapse since death, i.e., the radiocarbon age. The equipment developed and experiments performed to measure the specific activity of specimens to be dated are described. The results obtained by world-wide experimenters are discussed. These showed that on simultaneity radiocarbon dating is apparently reliable but that absolute dates may be incorrect by as much as 600 to 700 y. The value of radiocarbon dating to archaeologists, geologists, climatologists, and historians is stressed. (LCL)

The new DRAGON (Detector of Recoils And Gammas Of Nuclear reactions) facility, located at the TRIUMF-ISAC radioactive beams laboratory in Vancouver, Canada, has initiated its experimental program. Recently DRAGON was used for initial studies of the sup 2 sup 1 Na(p,gamma) sup 2 sup 2 Mg reaction. This facility was designed to measure absolutely the rates of radiative proton and alpha capture reactions of astrophysical interest to a precision of +-20%, using inverse kinematics. To fully understand the optics and operational parameters of the facility along with the transmission particularly of the reaction recoils, systematic studies of various configurations are in progress using stable beams along with measurements of well-known resonance reactions. The status of these commissioning studies is presented.

The heat is carried away from the surface by a loss of mass (liquid or vapor). ... A manometer that measures absolute pressure. absolute motion: Motion ..... reaction of the middle ear resulting from a difference in pressure between the gas in ...

A new method is described for crossed molecular beam measurements of differential cross sections. One of the reagent beams is labeled with a short-lived radioactive isotope, and detection utilizes counting of radioactive disintegrations. It is shown theoretically that for optimal sensitivity in crossed-beam scattering measurements, nuclides with half lives in the range 10/sup -5/--10/sup -1/ sec should be chosen for labeling. The usefulness of the new method was demonstrated by making measurements of differential cross sections for reactive scattering. The labeling nuclide chosen for development and testing was 0.032-sec /sup 217/At, and the chemical reactions used were Cl+HAt..-->..HCl+At and Br+HAt..-->..HBr+At. For the latter reaction, the total reaction cross section is only 1.5 A/sup 2/ under the conditions of the experiment. Background levels are sufficiently small that differential cross sections as small as 10/sup -2/ A/sup 2/ sr/sup -1/ could be measured at a resolution of 0.05 sr, if the primary beam intensity could be made large enough. One of the most useful features of this technique is that the measurement of absolute differential cross sections is readily carried out. Methods are described for making the requisite calibrations for the beam monitor and detector. In the prototype apparatus described here, the labeling nuclide was continuously generated by the radioactive decay of only 1--2 mCi of a long-lived precursor, 10-day /sup 225/Ac. However, it is calculated that on-line use of a nuclear accelerator to generate the short-lived nuclide will permit labeled beams 10/sup 5/ times more intense than those used in this demonstration experiment. Consequently, it should be possible to measure differential cross sections for reactions having total reaction cross sections significantly smaller than 1 A/sup 2/, and further development of this technique is therefore justified. (AIP)

Many elements have one or more naturally radioactive isotopes, and several hundred other radionuclides have been produced artificially. Radioactive substances may be present in natural water as a result of geochemical processes or the release of radioactive waste and other nuclear debris to the environment. The Geological Survey has developed methods for measuring certain of these .radioactive substances in water. \\r\

New research fields with the use of radioactive ion beams are now rapidly developing by virtue of recent progress in radioactive beam accelerators. The scientific and engineering researches on unstable nuclei far from stability are getting particular interests aiming at the full use of their radiation. In the circumstance many laboratories report utilizations and researches of the RI beam, the Tohoku University's renewal plan of the cyclotron and the short-lived nuclear beam facility at KEK have started. To discuss these new subjects on the scientific and engineering researches of unstable nuclei and on their nuclear methodology, the third specialist meeting was held at the KUR on February 16 and 17, 1998. Several noticeable and wide scope works on the method of RI-beam generation and on the new development of nuclear methodology have been reported, such as fundamental researches with laser, new isotope searchings and researches of nuclear structures with ISOL, in-beam nuclear spectroscopies through the deep-inelastic collision. In this meeting, especially, fundamental support-researches are reported, which are precise measurements of absolute disintegration rates, a gamma peak analysis method, evaluations of fundamental nuclear data, measurements of beta detector response functions for reducing Q values and precise measurement of high energy gamma intensities up to 11 MeV. The 14 papers are indexed individually. (J.P.N.)

This report compiles and summarizes all known radiometric age determinations based on bedrock samples from Tennessee. Data are available for 89 sites. Specimens record both igneous and metamorphic events ranging in age from 1.3 billion to 220 million years before present. Tennessee rocks have been dated by techniques that measure the results of four different kinds of radioactive decay: thorium-lead, uranium-lead, potassium-argon, and rubidium-strontium. Most determinations meet normal scientific standards for reliability. This study focuses on clarifying published data by bringing together geochemical, geological, and geographical information for each site. In addition to data on the age of bedrock samples, this study presents basic information on the ages of meteorites from Tennessee and on the ages of sediments and organic remains from Ice Age fossil sites and more recent archeological sites. While bedrock ages are the thrust of the report, other kinds of absolute age determinations are briefly discussed. 98 references, 11 figures, 3 tables.

Three practical applications of the defined solid angle absolute {beta} counting (DSAABC) method using end-window Geiger-Muller counter are presented. {sup 90}Sr and {sup 147}Pm nuclides were determined in filtered aerosol samples collected in Debrecen, Hungary, immediately after the Chernobyl accident. Development of an active method is in progress in order to determine radon and thoron daughters attached to airborne aerosols. Indoor concentrations were measured by this method in Ajka, Hungary, where radioactive industrial wastes were used as building materials. Determination of {sup 90}Sr and {sup 147}Pm in hot particles of Chernobyl origin, collected in Kiev, Ukraine, is in progress. The relation to the application of the DSAABC method is treated in detail and some results are presented. 1 fig., 3 tabs., 10 refs.

Meteorological radiosondes are launched routinely to obtain lower troposphere soundings of temperature, relative humidity, pressure, and wind parameters. The ability to carry extra sensors considerably extends the usefulness and cost-effectiveness of each sounding, permitting research into other properties of the lower atmosphere such as ozone, radioactivity, and electric field. An inexpensive four-channel digital data acquisition system is described which fits within the Vaisala RS80-15L radiosonde, for integration with other sensors. Using a 12-bit analog to digital conversion, a microcontroller formats the voltage measurements obtained for serial transmission over the radiosonde's UHF radio link at 300 baud. Maximum sampling rate on one channel is 10 Hz, which is reduced if multiple channels are sampled. The standard meteorological data telemetry is unaffected. During an entire flight in which the equipment experienced atmospheric temperatures from 4 deg. C to -55 deg. C, the absolute error on a 5 V fsd range was less than 15 mV.

The KMM + KMN Auger spectrum of Cu emitted in the electron capture decay of radioactive 65Zn in a solid state matrix was investigated for the first time at the instrumental energy resolution of 14 eV. Energies and relative intensities of twelve resolved spectrum components were determined and compared with theoretical predictions. A reasonable agreement of the semi-empirical calculations of transition energies by Larkins with experiment was observed. A comparison of theoretical and the measured transition rates indicates the important role of a coupling scheme applied. A more detailed analysis was hampered by absence of theoretical intensities for the individual intermediate coupling spectrum components. A slight indication of the influence of the source backing material on the absolute en...

Fission product contamination in many natural materials requires an efficient chemical procedure for the separation, purification, and absolute measurement of certain isotopes at very low levels. As part of the study of the distribution of long-range fallout from nuclear tests, a technique for the determination of both strontium-90 and barium-140 has been developed. The sample materials include bone, cheese, milk, vegetation, and soil. The first four sample types contain calcium phosphate as a major part of their ash. The separation of the phosphate from calcium, strontium, and barium is necessary for these sample types. Soils contain exchangeable calcium as well as non-exchangeable calcium in the silicate lattices. Since strontium and barium will follow calcium under the proper conditions, procedures were designed around the chemistry of calcium, which acts as a carrier for strontium and barium. In all cases the preliminary chemical procedure yields a calcium chloride solution carrying the radioactive strontium and barium. The radioactivity measurements are made on the daughters of strontium-90 and barium-140, that is yttrium-90 and lanthanum-140, respectively, which are extracted from the solution.

Isobarically purified beams of 77Cu with energies of 225 and 0.2 MeV were used at the Holifield Radioactive Ion Beam Facility of Oak Ridge National Laboratory to study ? decay into states in 77Zn. Data taken at 225 MeV allowed the determination of absolute branching ratios relative to the decay of 7...

Improved optoelectronic encoder measures absolute angle to which shaft has been rotated. Costs little more than older, less capable encoders do, yet measures absolute angles at high resolution and does not lose absolute-angle data because generates those data anew with each reading at up to 1,000 times per second. It accumulates increments to measure total angular interval through which shaft has been turned (including unlimited number of complete turns), as long as power remains on.

The report deals with 1. operation of SE (general aspects, maintenance, recurring tests, peculiarities); 2. monitoring of operation (temperature measurement, measurement of humidity, ventilation condensate, sump monitoring); 3. radiological data (personnel surveillance, aerosal activity, radioactive release with circulating and waste air, radioactive release via the waste water path, radon monitoring in SE, control of surroundings, radioactive wastes). (orig.).

Six months after the Chernobyl accident, a compilation of data measured by twelve radioactivity monitoring stations of the German Weather Service presents a time-related survey of radioactivity levels throughout the Federal Republic of Germany.

A new method, and first results for an impact energy 2 eV above the threshold of ionisation of helium, are presented for the measurement of absolute triple differential cross sections (TDCS) in a crossed beam experiment. The method is based upon measurement of beam/target overlap densities using known absolute total ionisation cross sections and of detection efficiencies using known absolute double differential cross sections (DDCS). For the present work the necessary absolute DDCS for 1 eV electrons had also to be measured. Results are presented for several different coplanar kinematics and are compared with recent DWBA calculations. (orig.).

Activity determination by gamma-ray spectrometry is a valuable aid which is widely used where radioactive sources are applied. For the construction of an efficiency curve vs. energy in a standard geometry, the accuracy is limited not only by the uncertainty of peak area determination and the knowledge of the relevant emission probabilities but also by the uncertainties of the activity values applied to efficiency calibration with standard sources. Recently, a method to determine a relative efficiency function using selected radionuclides with gamma cascades of well known emission probabilities has been developed which yields very accurate efficiency values. Such a curve has to be converted into an absolute efficiency curve by calibration of the detector system with at least one source of very well known activity. Especially for this purpose, a set of Co-60 gamma-ray spectrometer sources was produced at the PTB. The activity values (10-45 kBq) were measured by the 4pi beta-gamma coincidence technique with a standard uncertainty of less than 0.1%. Production and measurement of these sources are described in the present paper. Special care was taken to include all contributions to the standard uncertainty of the activity value when establishing the uncertainty budget for the activity of each of these sources. The activity ratio of two of these sources, as obtained by the absolute measurements, was checked by independent gamma-ray counting at two other laboratories, where the precision achieved was less than 0.2%. The procedure described is considered to be a step towards more accurately determined efficiency functions in gamma-ray spectrometry. PMID:11839019

The value of the electron capture branching ratio of 7Be to the 478 keV state in 7Li has been measured using sources of determinable intensity fabricated by capturing in silicon surface barrier detectors 7Be recoils from the 10B(p, ?)7Be reaction at Ep=1.5 MeV and 4.5 MeV Results from independent measurements utilizing detectors implanted in a scattering chamber and in the focal plane of a magnetic spectrograph are in good agreement. An absolute determination of the rate at which the 478 keV gamma rays were emitted from each source yielded a weighted average value of 10.6+/-0.5% for the branching ratio. This result is in agreement with the previously accepted value of 10.37+/-0.12% and does not support the recent suggestion that the branching ratio is appreciably larger. RADIOACTIVITY 10B(p, ?)7Be, E=1.5, 4.5 MeV; enriched target; measured I7Be; silicon surface barrier detector; measured E?, I? Ge(Li) detector; deduced branching ratio of 7Be to 478 keV state in 7Li.

The measurement of blood-plasma absolute velocity distributions with high spatial and temporal resolution in vivo is important for the investigation of embryonic heart at its early stage of development. We introduce a novel method to measure absolute blood flow velocity based on high speed spectral ...

Waste drums containing remote-handled (RH) transuranic (TRU) waste from the Argonne National Laboratory-East (ANL-E) are stored in sealed, underground vaults at the Radioactive Waste Management Complex (RWMC) at the Idaho National Engineering and Environmental Laboratory (INEEL). The waste consists of laboratory debris from the destructive examination of fuel elements irradiated mostly in the Experimental Breeder Reactor II (EBR-II). In 2004, air samples were obtained from some of these vaults and analyzed for radioactivity. Some of the samples show that the vaults contained several DAC's (derived air concentrations) of tritium, which are considered as non-negligible by Environmental Protection Agency (EPA) regulations. Based on Acceptable Knowledge (AK) records of the waste stored in the vaults, ORIGEN2 calculations were performed to estimate the isotopic contents in the waste drums stored in the vaults. The calculations are based on the irradiation of fuel elements that produced the waste. The absolute amounts of isotopic contents in the waste drums are normalized to Cs-137 contents derived from measured surface dose rates, mostly from the Cs-137 radiation, as documented in AK records. The amounts of tritium thus calculated (assuming no loss from those produced during fission except for decay) are compared to the measured values in the air samples from the vaults. The ratio of measured tritium in the form of tritiated water vapor to un-reduced tritium from fission is found to be from below detection levels to approximately 0.2%, but mostly in the range around 1 10-4 to 1 10-3. It appears that even the debris from cutting and grinding the fuel elements contained substantial amounts of tritium, which were subsequently released from the fuel particles during years of storage in the vaults.

A method of absolute nuclear material assay of an unknown source comprising counting neutrons from the unknown source and providing an absolute nuclear material assay utilizing a model to optimally compare to the measured count distributions. In one embodiment, the step of providing an absolute nuclear material assay comprises utilizing a random sampling of analytically computed fission chain distributions to generate a continuous time-evolving sequence of event-counts by spreading the fission chain distribution in time.

Establishing a chronology for polar ice is vital to interpreting the climatic record preserved in ice. There is, at present, no method for dating ice absolutely beyond 50,000 years. The goal of the project is to establish a method for dating ice in the range of 50,000 to 1,000,000 years based on measuring cosmogenic 81Kr (half-life = 213,000 y) in air trapped by the ice. The 81Kr technique comprises the following steps: (1) extraction of ancient air from the ice, (2) separation of Kr from air, (3) separation of 81Kr from stable Kr, and (4) direct detection of 81Kr using resonance ionization time-of-flight spectrometry. Feasibility of the methodology was demonstrated by measuring 81Kr in 168 kg of ice collected from the Allan Hills area of Antarctica. The 81Kr age was determined to be 108,000 y (+82,000, -55,000). The 85Kr content of the ice, measured by the same technique, was 17 percent modern suggesting that the ice may have been contaminated in situ with modern air. Improvements in equipment should enable dating of less than 30 kg of ice or groundwater to within a few percent. Applications of the technique include environmental monitoring and tracer studies (85Kr) and groundwater dating (81Kr) for radioactive waste disposal site selection.

A set of partial working procedures has been designed for laboratory modelling and measurement of affecting termite caste differentiation by a juvenogen. The developed measuring system is based on selection of termite individuals by transmission X-ray radiography and by radioactivity measurement of the selected individuals. It permits to use only a single worker and a single soldier from the whole experimental group to evaluate their different radioactivities as well as the ratios of these values to the radioactivity applied into the experiment.

The ability of a variety of chemical and physical agents to stimulate DNA repair synthesis in human cell cultures was tested by a simplified scintillometric procedure, with the use of hydroxyurea (HU) to suppress DNA replicative synthesis. After incubation with (/sup 3/H)thymidine, the radioactivity incorporated into DNA was determined in controls (C) and treated (T) cultures and in the corresponding HU series (Csub(HU), Tsub(HU)). The ratios Tsub(HU)/Csub(HU) and Tsub(HU)/T:Csub(HU)/C, indicating absolute and relative increases of DNA radioactivity, were calculated. When both ratios were significantly higher than 1, they were taken as indices of DNA repair stimulation.

A fuel limit controller includes a computer supplying a commanded absolute EGR control pressure that is a measure of fuel supplied per diesel engine revolution. An absolute EGR control pressure equal to the commanded absolute pressure is generated from a subatmospheric pressure source and atmospheric air so that the absolute EGR control pressure is limited to atmospheric pressure. Fuel per engine revolution is limited to the value represented by the absolute EGR control pressure so that the fuel limit is automatically compensated for altitude variations. The rate of change in the fuel limit in response to changes in the absolute EGR control pressure is limited to delay increases in fuel to match the time to purge excess exhaust gases from the engine intake manifold.

There are several basic characteristics of mass spectrometry that are not always fully appreciated by the science community. These characteristics include the distinction between relative and absolute isotope abundances, and the influence of isotope fractionation on the accuracy of isotopic measurements. These characteristics can be illustrated in the field of nuclear physics with reference to the measurement of nuclear parameters, which involve the use of enriched isotopes, and to test models of s-, r-, and p-process nucleosynthesis. The power of isotope-dilution mass spectrometry (IDMS) to measure trace elements in primitive meteorites to produce accurate Solar System abundances has been essential to the development of nuclear astrophysics. The variety of mass spectrometric instrumentation used to measure the isotopic composition of elements has sometimes been accompanied by a lack of implementation of basic mass spectrometric protocols which are applicable to all instruments. These metrological protocols are especially important in atomic weight determinations, but must also be carefully observed in cases where the anomalies might be very small, such as in studies of the daughter products of extinct radionuclides to decipher events in the early history of the Solar System. There are occasions in which misleading conclusions have been drawn from isotopic data derived from mass spectrometers where such protocols have been ignored. It is important to choose the mass spectrometer instrument most appropriate to the proposed experiment. The importance of the integrative nature of mass spectrometric measurements has been demonstrated by experiments in which long, double beta decay and geochronological decay half-lives have been measured as an alternative to costly radioactive-counting experiments. This characteristic is also illustrated in the measurement of spontaneous fission yields, which have accumulated over long periods of time. Mass spectrometry is also a valuable tool in the determination of neutron capture cross-section measurements and the application of such determinations in Planetary Science. PMID:19877268

[{sup 11}C]FLB 457 is a radioligand for positron emission tomography (PET) that possesses high affinity to D{sub 2}/D{sub 3} receptors. It has been suggested to be useful for quantification of low-density dopamine D{sub 2} receptor populations, e.g. in cortical and limbic brain areas. We explored the reproducibility of five methods for measuring extrastriatal D{sub 2}-like receptor binding potential with [{sup 11}C]FLB 457. Seven healthy male volunteers were examined twice with [{sup 11}C]FLB 457 (high specific radioactivity) on the same day, at least 3 h apart. Four brain areas, frontal cortex, nucleus thalamus, temporal cortex and cerebellar cortex, were examined. Binding potentials (BPs) were derived from (1) a target to cerebellum distribution volume ratio, (2/3) two reversible reference tissue compartment models and (4) a transient equilibrium approach. For comparison, BP values were also calculated with the standard three-compartment kinetic model that does not assume a receptor-free reference region. The use of the standard three-compartment model did not result in reproducible BP estimates. The distribution volume (DV) ratio, reference tissue compartment models and the transient equilibrium method all had good to excellent intraclass correlation coefficients (ICCs) in the studied brain areas ranging from 0.56 to 0.93. Absolute variability was also relatively low, ranging from 5.3% to 10.4%. There were no marked differences in the ICC or absolute and relative variability between the four methods based on a reference tissue (cerebellum). In addition, we did not observe systematic differences in the BP between the first and the second scan. These data indicate that the reproducibility of the DV ratio, reference tissue models and the transient equilibrium method is good or excellent. However, each of these methods includes assumptions affecting their validity. Thus, the choice of method will be critically dependent on the purpose of the study. (orig.)

The National Laboratory for Ionizing Radiation Metrology, of the Institute of Radiation Protection and Dosimetry, of the National Commission on Nuclear Energy (IRD/CNEN), comes leading a comparison program for activity measurements of radiopharmaceuticals administered to patients in the Nuclear Medicine Services (NMS) with the purpose to promote the quality control. This work presents a quality assurance program for the performance of such measurements, evaluated in the comparison runs between hospitals and LNMRI, under the statistic point of view and the compliment of regulatory authority norms. The performance of the radionuclides {sup 67}Ga, {sup 123}I, {sup 131}I,{sup 99m}Tc and {sup 210}Tl were evaluated and {sup 201}TI have been standardized by absolute methods. Besides, it was established the traceability of the radioactivity standards used in nuclear medicine and a methodology for implementation of a national metrology net of radionuclides. The comparison results prove that the implementation of a radionuclide metrology net is viable, important and feasible. (author)

This patent describes an asphaltic composition of enhanced utility for vehicular pavement which composition comprises a road paving grade of asphalt in admixture with at least one alkylene dithiocarbamate. The composition is characterized by having a reduced increase in absolute viscosity to original absolute viscosity after thin film aging as measured by ASTM Test D 1754 at 140/sup 0/F.

Synchrotron radiation measurements of near-threshold and broad-range (20 eV - 3 keV) absolute photoabsorption cross sections were made at the Brookhaven National Laboratory (NSLS) and at Stanford (SSRL). Transmission data for well-characterized multilayer foils provided absolute cross sections with ...

A multi-channel time-scaling (MCTS) technique has been applied for an absolute standardization of a sup 5 sup 7 Co solution using a 4 pi (e sup - , X) -gamma coincidence counting method. Four radioactive samples were prepared and the nominal activities observed in the proportional counter were from 700 to 1400 s sup - sup 1. The true coincidence rates together with the corresponding electron capture detection efficiencies can be obtained experimentally. The results are compared with those calculated from mathematical formulae.

Absolute efficiency calibration of radiometric detectors is frequently difficult and requires careful detector modeling and accurate knowledge of the radioactive source used. In the past we have calibrated the ??? coincidence detector of the Automated Radioxenon Sampler/Analyzer (ARSA) using a variety of sources and techniques which have proven to be less than desirable (Reeder et al., J Radioanal Nucl Chem, 235, 1989). A superior technique has been developed that uses the conversion-electron (CE) and X-ray coincidence of 131mXe to provide a more accurate absolute gamma efficiency of the detector. The 131mXe is injected directly into the beta cell of the coincident counting system and no knowledge of absolute source strength is required. In addition, 133Xe is used to provide a second indep...

An apparatus is claimed for measuring the concentration of radioactivity in a radioactive fluid discharged from a nuclear power plant. The apparatus comprises a radioactivity concentration measurement pipe arranged to extend vertically, fluid supplying means for supplying the fluid into the measurement pipe in such a manner that the fluid flows down through the measurement pipe along the axis of the measurement pipe without contacting the inner surface of the latter, radioactivity concentration measuring means disposed at the outside of the measurement pipe for measuring the radioactivity concentration in the fluid flowing in the measurement pipe, and means for discharging the radioactive fluid to the outside of the measurement pipe. The apparatus further comprises a gas supply pipe opening at its one end to the atmosphere and communicated at its other end with the inside of the measurement pipe, and a check valve disposed in the gas supply pipe and operated at a pressure higher than the atmospheric pressure. When the pressure in the measurement pipe has come down below the atmospheric pressure, the check valve is operative to always maintain the internal pressure in the measurement pipe at the atmospheric pressure, thereby to prevent the fluid level in the measurement pipe from being raised to reduce the background noise during the measurement of the radioactivity concentration.

Atmospheric 222Radon concentration measurements are used as a valuable transport tracer verifying the transport part of Carbon Cycle and Greenhouse Gas models. The production rate of the radioactive noble gas 222Radon (T1?2 = 3.8 days) by radioactive decay of 226Radium in the soil is constant, the absolute quantity depending on the local soil Radium concentration. The flux of 222Radon to the atmosphere (the soil exhalation, or effective atmospheric production rate), however, is not constant. It strongly depends on soil texture, soil humidity, precipitation and other parameters, but is nearly constant if these parameters stay unchanged. Recently, an effort has been done to predict this flux rate with widely available γ-dosimetry measurements (Szegvary et al., Predicting terrestrial 222Rn-flux using gamma dose rate as a proxy, ACP 7, 2789-2795, 2007), but real 222Radon-flux measurements are sparse. 222Radon undergoes the same transport processes on the way from soil to atmosphere as any other soil-derived (greenhouse) gas. This makes 222Radon an ideal tracer to separate variations in e.g. soil CO2-production from changes in the soil-atmosphere CO2-transport, both being reflected in the total soil-atmosphere CO2-flux. At the atmospheric measurement site Lutjewad in the north of the Netherlands (53N24'18", 6E21'13", www.rug.nl/ees/onderzoek/cio/projecten/atmosphericgases) we started in 2006 with the measurements of the soil 222Radon and CO2 concentration through soil probes as well as the Radon and CO2 soil fluxes by means of an automatic soil chamber. While there are up to eight soil air measurements per day, the soil chamber is automatically closed twice per day. The station is situated directly on the Waddensea dike at an elevation of 1 m a.s.l. on seaclay soil. The groundwater table shows variations between 0.5 m and 2 m below terrain. From our measurements we find that in the dryer summer season, from April to July, the mean 222Radon-flux can be up to 40 % higher than the during the rest of the year, but the variability is generally very high. Short-term flux minima are mainly due to precipitation events. First results will be shown of the parameterization of the 222Radon and CO2 fluxes with the groundwater level, soil temperature and humidity, rain events and atmospheric pressure changes.

In order to make clear appreciation to induced radioactivity in the irradiated foods, photonuclear reactions which could produce radioactivity at energies up to 10 MeV were listed up from elemental compositions of black pepper, white pepper, red pepper, ginger and turmeric. The samples were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy and radioactivity was measured. Induced radioactivity could not be detected significantly by gamma-ray spectrometry and beta-ray counting in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H[sub 50] according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from [sup 40]K contained in the samples. (J.P.N.).

We measured absolute double capture cross section of Cn+ ions (n=1,5) colliding, at 2.3 and 2.6 a.u velocities, with an Helium target atom and the branching ratios of fragmentation of the so formed electronically excited anions Cn?*. We also measured absolute cross section for the electronic attachment on neutral Cn clusters colliding at same velocities with He atom. This is to our knowledge the first measurement of neutral-neutral charge exchange in high velocity collision.

In the framework of the Medipix collaboration the PCC, a single photon counting pixel chip, has been developed with the aim of improving the contrast resolution in medical imaging applications. The PCC consists of a matrix of 64x64 square pixels with 170 mm side length, each pixel comprising a 15 bit counter and a pulse height discriminator. The chip has been bump bonded to equally segmented 200 mm thick SI-LEC GaAs detectors showing a very high absorption energy for X-rays used in diagnostics. An absolute calibration of the system with a radioactive source and a synchrotron beam are described resulting in the value of the test input capacitance of ~24.7 fF. Using this value a full characterisation of the system from electrical measurements is presented. The entire system can reach a minimum threshold of ~2100 e- with ~250e- rms noise. One of the characteristics of the PCC is the possibility to adjust the thresholds of all pixels on a pixel-by-pixel basis with 3-bit precision. The threshold distribution after...

Determination of radium, thorium, uranium isotopes, and /sup 210/Pb in sediments and sediment pore waters from North Equatorial Pacific deep-sea clay-silicous oozes shows that the radium and uranium isotopes are mobile in the pore water. The concentration-depth profiles of radium can be understood in terms of a diagenetic model which takes into account mixing of sediment particles by bioturbation, molecular diffusion in the pore water, adsorption onto particle surfaces, as well as radioactive production and decay. The /sup 234/U//sup 238/U activity ratios in several samples are higher than the seawater value, indicating some enrichment of /sup 234/U in the pore water. However, the absolute concentrations of /sup 238/U and /sup 234/U are 25% lower than those in seawater, suggesting that the sediments form a sink for uranium isotopes. /sup 210/Pb is present in the pore water at concentrations approx. 20% that of /sup 226/Ra. The origin of /sup 210/Pb in the pore water is uncertain and could be due either to its in situ mobilization in the sediments or subsequent production in the laboratory from the decay of /sup 222/Rn. /sup 230/Th is present in measurable concentrations in the pore waters, but its distribution does not show any systematic trend with depth or other parameters. The most likely source of /sup 230/Th appears to be minute amounts of sediment particles collected in the pore waters during the squeezing operation.

In this study, we report on the development of the production technique of radioactive sources suitable to precisely calibrate the energy and detection efficiency of the semiconductor gamma detectors. We developed totally 4 calibration sources, {sup 137}Cs and {sup 60}Co producted from HANARO reactor at Korea Atomic Energy Research Institute and {sup 152}Eu, mixed source {sup 154+155}Eu. In order to investigate the special qualities of these calibration sources, the mass absorption coefficients, due to the thickness of source container, were systematically measured. And the absolute detection efficiency curve of the used Ge detector was obtained by using the standardized source {sup 152}Eu. The activity of a mixed source {sup 154+155}Eu is determined with assistant of the resulted detection efficiency curve. As a result, the detection efficiency curve can be determined overall the energy regions from 0 keV to 2000 keV by using this mixed calibration source. The activity of each {sup 137}Cs, {sup 60}Co and {sup 152}Eu is obtained and the uncertainty of each activity is evaluated by root square sums of each uncertainty component arising from the decay parameters, and from the counting statistics, and from the used standard source, and from the fraction of losses to pass out the source and from the sample impurities. Total error was found to be 1.2 % above the ranges of the knee point 150 keV and to be 4.5 % below the regions of the point. 8 refs., 8 figs., 7 tabs. (Author)

Methods for non-contact tests with ultrasonics produced by lasers on glowing or radioactive components are dealt with here. In particular, a heterodyne interferometer is described for the wide band testing of normal ultrasonic deflections and is compared with other types of interferometers. Applications such as the determination of grain size in thin sheets and the absolute determination of the ultrasonic deflections achieved are demonstrated. By means of reconstruction of the signal beam by the application of optical phase conjugation, the 'etendue' (ability to collect light) was improved from 2.6x10/sup -7/ to about 1x10/sup -2/, so that the use of this type of interferometry is possible, even on rough surfaces. A capacitative sensor was used for the quantitative measurement of the characteristics of the ultrasonic field produced by a laser, as the sound deflection in these experiments lay below the sensitivity threshold of the interferometer. A simple optical process for testing acoustic surface waves is described. (orig./HP).

Measurement of regional myocardial blood flow (RMBF) is crucial in experimental studies of myocardial ischemia and reperfusion in dogs. The standard measurement technique uses radioactive microspheres; however, not all institutions are able to dispose of radioactive waste and therefore cannot make use of this method. We tested a new, nonradioactive microsphere, labeled with colors instead of nuclides. Simultaneous blood flow measurements with two nuclide-labeled and two colored microspheres were performed after coronary occlusion in dogs. Both techniques show a within-method correlation of r greater than 0.98. Duplicate variability for paired RMBF values in 80 samples was 8.7 +/- 0.1% when computed with radioactive microspheres and 13.2 +/- 1.8% when computed with colored microspheres. There was a good correlation in the measurement of RMBF between the radioactive- and colored-microsphere methods (r = 0.98). The best-fitting linear regression line was expressed by the formula: Colored-microsphere RMBF = 1.11 (radioactive-microsphere RMBF)-0.02. When measured by colored microspheres, RMBF was approximately 8% higher than when computed with radioactive microspheres for blood flow values of 0-2 ml/min/g. When blood flow was increased pharmacologically to levels of 2-7.5 ml/min/g, colored microspheres yielded blood flow values 39% higher than the values computed by radioactive microspheres. We conclude that the nonradioactive, colored-microsphere method correlates with the radioactive technique, but at high flows, it yields values greater than those obtained with radioactive microspheres.

Further development of the concept of traceability in low level radioactivity measurements is important in light of the growing practice by government agencies to adopt regulations that require that radioactivity measurements be traceable to national standards. Several definitions of traceability are evaluated. Similarities, differences, and implications of these definitions are discussed. 5 references.

A radiation source is prepared by an extremely simple means of dropping a solution of radioactive material to a surface of porous glass or immersing porous glass into a solution of radioactive material. For instance, 10 {mu}l of a solution of gadolinium chloride is dropped to the surface of porous glass dehydrated to dry in air for about 2 hours at 120degC and dried spontaneously. In this case, the amount of radioactive gadolinium (Gd-153) absorbed per one piece of porous glass measured by radioactivity was 0.67 mg. Further, porous glass of the identical size and type with that in the above example was soaked into a solution of gadolinium chloride for 10 min. After soaking, it was dried spontaneously and the amount of radioactive gadolinium absorbed per one piece of the porous glass measured by radioactivity was 0.28 mg. (T.M.).

May 14, 2012 ... RS operates in the spectral range from 320 to 2300 nanometers with 8 ... The IR instrument will utilize a blackbody reference source with Phase ... (PCCs) to accurately measure the absolute temperature and deep space as ...

mapped sea surface temperature products during the first six .... The absolute accuracy is relative to a NIST traceable blackbody target located at nadir viewing position (Pagan0 et al., .... measurements are made in the range from 550 to ...

blackbody temperature and emissivity measurement be known on-orbit. We present novel ... across a range of temperatures. The top panel shows the .... Revercomb, 2008: On-orbit absolute calibration of temperature with application to the ...

2004 "Measurements of primary and atomospheric cosmic-ray spectra with the ... and muon spectra at small atmospheric depths with the BESS spectrometer," K Abe ... 2000 "The absolute flux of protons and helium at the top of the atmosphere ...

(a) Provide quality assessed Saudi Arabian surface solar radiation data .... upwelling shortwave (albedo) measurements; an Eppley Hickey-Frieden Absolute Cavity ... extensive BSRN data sets, network calibration histories, and zenith angle ...

individual changes were statistically significant, the absolute values were .... Fink, M. EEG profiles and bioavailability measures of psychoactive drugs. In T. M. Itil ( Ed.), ... Knott, J. R. Brain ,potentials during silent and oral reading. J. Gen.

Due to rapid improvements in high-power laser performance, two-photon absorption processes have become a very useful tool for studying the molecular structures of various gases, liquids and solids. However, measurements of absolute two-photon absorption cross sections were more or less ignored previously because of their small size. In this work, we obtained not only the two-photon absorption spectra, but also measurements of their absolute cross sections for various gases, liquids, and solids. 8 refs., 1 fig., 1 tab.

Primary and atmospheric cosmic-ray spectra were precisely measured with the BESS-TeV spectrometer. The spectrometer was upgraded from BESS-98 to achieve seven times higher resolution in momentum measurement. We report absolute fluxes of primary protons and helium nuclei in the energy ranges, 1-540 GeV and 1-250 GeV/n, respectively, and absolute flux of atmospheric muons in the momentum range 0.6-400 GeV/c.

With the first data sample collected by the CLEO-c detector at the psi(3770) resonance we have studied four exclusive semileptonic decays of the D0 meson. Our results include the first observation and absolute branching fraction measurement for D0 --> p-e+ve and improved measurements of the absolute branching fractions for D0 decays to K-e+ve, pi-e+ve, and K*-e+ve. PMID:16383893

Comparisons are reported between measured and predicted levels of induced radioactivity for a number of irradiation conditions. Good agreement was found between experimental measurements and fairly simple methods of prediction developed at CERN.

In this article, the Recoil Distance Doppler-Shift (RDDS) method which is extensively used in nuclear structure physics to determine level lifetimes and absolute transition probabilities is reviewed. Especially, it is aimed to present new developments and variants of the technique which have evolved mainly in the past 25 years. After a short and comprehensive description of the basic elements of the plunger technique, the new variants are presented. This comprises the RDDS technique using ??-coincidences, RDDS measurements in combination with particle detectors for selecting specific reaction channels, RDDS after Coulomb excitation, RDDS after fission and RDDS using a gas target. In addition, the concept of a differential plunger is discussed with respect to its specific features and typical experimental setups. Examples of differential plunger measurements with recoil tagging, recoil decay tagging and after deep inelastic reactions, Coulomb excitation in inverse reaction kinematics as well as after reactions with fast radioactive beams at energies of 50-100 MeV/u are given. The second focus of the review is dedicated to today's plunger devices and related hardware. The concepts of specific plunger devices which accommodate the specific demands of the aforementioned RDDS applications including specific feedback systems for controlling target-stopper/degrader separations in-beam are presented. Also discussed are target and stopper/degrader foil related issues like foil preparation, mounting and stretching as well as specific features of the foil behavior in-beam (temperature, blistering, wrinkling and carbon build-up). The third focus is devoted to the data analysis. The concept of the Differential Decay Curve Method (DDCM) is presented as an alternative approach for the analysis of RDDS data measured as singles or as ??-coincidences. For the latter, different gating possibilities are discussed, e.g. gating from above and gating from below the level of interest and gating on fractional components. Finally, the simulation of line-shapes and its application is presented.

An automated electrodeposition system for the preparation of radioactive stents and an automated dosimetry system based on the Optidos beta-scintillation detector for the quality control of the radioactive stents have been developed. Custom-made application software programmed in Visual Basic was used to control liquid flow and electroplating currents in the electrodeposition system, and to run the dual motion actuator and radiation detector for the automated measurement of the radioactivity distribution. The automation of the electroplating process increased the precision, ease, repeatability, and radiation safety of the process. The radioactive beta-emitting 188Re stents might be useful for the treatment of patients with inoperable lung cancer. PMID:15388127

The increasing use of radioactive microspheres in large animal research poses a growing problem in waste management for many institutions. Incineration, with its obvious volume reduction benefits, is an economically attractive means of disposing of carcasses containing radioactive microspheres. Although it is generally assumed that incinerated microspheres remain with the ash, few studies have been performed to actually quantify the fraction of radioactivity emitted in the effluent. The present paper presents results of actual measurements of radioactivity in the effluent during the incineration of carcasses containing microspheres labelled with several different radionuclides.

After the Great East Japan Earthquake and resulting Tsunami on March 11, 2011, serious accident of the Fukushima Dai-ichi Nuclear Power Plant has been occurred. Huge amounts of radionuclides were released in atmosphere and ocean. Japanese prefectural governments have carried out environmental radioactivity monitoring; external dose rate, radioactivity measurements in environmental samples and others. Since March 18, 2011, daily and monthly deposition samples were collected in 45 stations covering Japanese Islands and radionuclides in the deposition samples were determined. We summarize radioactive deposition data reported by Japanese Government and study the depositional behaviors of the Fukushima-derived radionuclides. The results revealed that Fukushima-derived radioactive cloud dominant...

The natural radioactivity of soils at the Xiazhuang granite massif of Southern China has been studied. The radioactivities of 55 samples have been measured with a low-background HPGe detector. The radioactivity concentrations of (238)U and (40)K ranged from 40.2 to 442 and from 442 to 913 Bq/kg, respectively, while the radioactivity concentration of (232)Th varied only slightly. In order to evaluate the radiological hazard of the natural radioactivity, the radium equivalent activity (Ra(eq)), the absorbed dose rate (D ), the annual effective dose rate and the external hazard index (H(ex)) have been calculated and compared with the internationally approved values. The study provides background radioactivity concentrations in a granite area, specifically, the area in the vicinity of a uranium mine in Southern China. The data can be used in exploring granite-type uranium deposits. PMID:15922605

It was shown that crossed-sightline ECE (electron-cyclotron-emission) can be used for both local measurement of fluctuating quantities (electron temperature and density), and also for inferring the local value of the absolute magnetic field in present experiments, or in a reactor environment. The absolute magnetic field measurement is a direct measure of the local plasma pressure ([beta]) in currentless devices, and in combination with temperature and pressure measurements is a measurement of the plasma current density in devices with significant plasma current. Calculations show that absolute measurements of magnetic field can be made to the order of 0.1%, even in a reactor environment, and that a scanning ECE system could be used to measure the beta profile or current profile in a reactor, as appropriate. The electron temperature fluctuation measurements have a similar resolution, and can also show the phase between density and temperature fluctuations, an extremely important quantity for understanding transport caused by these fluctuations.

The patented VAC*TRAX process was designed in response to the need to remove organic constituents from mixed waste, waste that contains both a hazardous (RCRA or TSCA regulated) component and a radioactive component. Separation of the mixed waste into its hazardous and radioactive components allows for ultimate disposal of the material at existing, permitted facilities. The VAC*TRAX technology consists of a jacketed vacuum dryer followed by a condensing train. Solids are placed in the dryer and indirectly heated to temperatures as high as 2600{degrees}C, while a strong vacuum (down to 50 mm Hg absolute pressure) is applied to the system and the dryer is purged with a nitrogen carrier gas. The organic contaminants in the solids are thermally desorbed, swept up in the carrier gas and into the condensing train where they are cooled and recovered. The dryer is fitted with a filtration system that keeps the radioactive constituents from migrating to the condensate. As such, the waste is separated into hazardous liquid and radioactive solid components, allowing for disposal of these streams at a permitted incinerator or a radioactive materials landfill, respectively. The VAC*TRAX system is designed to be highly mobile, while minimizing the operational costs with a simple, robust process. These factors allow for treatment of small waste streams at a reasonable cost.

The measuring technique of radioactive activity by the coincidences method 4 {pi} {beta}{sup -} {gamma} it requires of the elaboration of radioactive sources on thin supports in order to flows the biggest percentage of beta particles, those of the order of the 80 % or but. In this work a procedure for the elaboration of this type of sources, with gilding Vyns is reported. (Author)

This report is a compilation of the calendar year 2005 groundwater sampling results from the Area 5 Radioactive Waste Management Site. In additon to providing groundwater monitoring results, this report also includes information regarding site hydrogeology, well construction, sample collection, and meteorological data measured at the Area 5 Radioactive Waste Management Site at the Nevada Test Site, Ny County, Nevada.

Rapid yet accurate measurement of the {sup 131}I activity in the thyroid gland as well as in the air, water and vegetation may have an important role in obtaining quantitative information on internal doses for the people living in the vicinity of nuclear facilities shortly after an accidental release of radionuclides. Whole body counting technique is still the standard method for measuring radionuclides in the body while necessity for in situ measurement techniques has considerably increased especially after the Three Mile Island and Chernobyl accidents. For measurement of {sup 131}I in the thyroid gland in emergency situations, NaI (Tl) detectors, as in a scintillation survey meter as in the simplest case, are most often used while measurement of urinary excretions for members of the public may also effective. The scintillation survey meter method, being easily implemented, may not have enough selectivity for radioiodine and even be liable to an elevated background radiation spectrum. This would possibly lead to higher detection limits and lower accuracy. A use of a laboratory Ge (Li) detector system in the thyroidal radioiodine measurement was suggested to overcome the problem. A real measurement with a similar instrument was reported for the residents in U.K. after the Chernobyl accident. A use of a scintillation spectro-survey meter with a NaI (Tl) probe with lead collimation to thyroidal radioiodine measurement was also reported to give satisfactorily accurate evaluation of the thyroidal {sup 131}I burden. In this paper, a movable Ge system was developed for the above purpose and preliminarily evaluated particularly for counting efficiency. It is consisted of a portable high-purity Ge detector and a battery-operated MCA. It employs a laboratory made thin Pb shield with a collimation window and an elevator for the detector platform. The elevator was designed to adjust the height of the thyroid radioiodine probe in relation to the height and position of the neck of a subject sitting in a chair. Gamma spectra were analyzed and stored by the portable MCA. The acquired spectral information, sent to a notebook computer on line, was processed for determination of the {sup 131}I activity. In the preliminary measurement, the system was checked for its counting efficiency for {sup 131}I radioactivity by using neck-thyroid phantoms for the adult and some different ages that were previously prepared. The absolute counting efficiency was observed to be satisfactory, i.e. 0.20 to 0.28%. However, it was suggested that certain modification in the shield part of the probe might improve counting efficiency. (author)

In order to perform quantitative gamma spectroscopy, it is necessary to know the sample-specific detection efficiency for photons as a function of energy. The detection efficiency, along with the branching ratio for the isotope and gamma ray of interest, is used to convert observed counts/second to actual disintegrations/second, and, hence, has a large effect on the accuracy of the measurement. In cases where the geometry of the source is simple and reproducible, such as a point source, small vial of solid, or jar of liquid, geometry-specific standards may be counted to determine the detection efficiency. In cases where the samples are large, irregular, or unique, this method generally cannot be used. For example, it is impossible to obtain a NIST-traceable standard glovebox or 55-gallon drum. In these cases, a combination of measured absolute detector efficiency and calculated sample-specific correction factors is commonly used. The correction factors may be calculated via Monte Carlo simulation of the item (the method used by Canberra's ISOCS system), or via semi-empirical calculation of matrix and container attenuations based on the thickness and composition of the container and radioactive matrix (ISOTOPIC by EG&G Ortec uses this method). The accuracy of these correction factors for specific geometries is often of vital interest when assessing the quality of gamma spectroscopy data. During the Building 251 Risk-Reduction Project, over 100 samples of high activity actinides will be characterized via gamma spectroscopy, typically without removing the material from the current storage containers. Most of the radioactive materials in B-251 are stored in cylindrical stainless steel canisters (called USV containers, after the Underground Storage Vaults they are commonly stored in), 13 cm in diameter, by 28 cm high, with walls that are 1.8 mm thick. While the actual samples have a variety of configurations inside the USV container, a very common configuration is the material (usually as an oxide powder pellet of approximately 2 cm diameter by {approx}2 mm thick) in a squat glass jar, with the jar placed in a thin steel food-pack can, which is then placed in the bottom of the USV canister. During data acquisition, the USV containers are typically rotated at approximately 4 rpm on a turntable to eliminate errors due to the material not being centered in the can, or attenuation not being isotropic. An aluminum plate is placed over the container, secured by three vertical rods, to securely hold the container. Pictures of both the containers, and this typical counting configuration are shown below.

The absolute cross sections for the production of N(+) and N2(+) have been measured from the dissociative ionization threshold to 115 A. In addition, the absolute photoabsorption and photoionization cross sections are tabulated between 114 and 796 A. The ionization efficiencies are also given at several discrete wavelengths between 660 and 790 A. The production of N(+) fragment ions are discussed in terms of the doubly excited N2(+) states with binding energies in the range 24 to 44 eV.

We report here on the new realization of an automatic fluxgate theodolite able to perform unattended absolute geomagnetic declination and inclination measurements: the AUTODIF MKII. The main changes of this version compared with the former one are presented as well as the better specifications we expect now. We also explain the absolute orientation procedure by means of a laser beam and a corner cube and the method for leveling the fluxgate sensor, which is different from a conventional DIflux theodolite.   

Data were collected with the AGS internal (E880) polarimeter at G{gamma} = 12.5 during the FY04 polarized proton run. Measurements were made with forward scintillation counters in coincidence with recoil counter telescopes, permitting an absolute calibration of the polarimeter for both nylon and carbon targets. The results are summarized and they will also be useful for an absolute calibration of the AGS CNI polarimeter at G{gamma} = 12.5.

An extension of the X-ray extended-range technique is described for measuring X-ray mass attenuation coefficients by introducing absolute measurement of a number of foils - the multiple independent foil technique. Illustrating the technique with the results of measurements for gold in the 38-50 keV energy range, it is shown that its use enables selection of the most uniform and well defined of available foils, leading to more accurate measurements; it allows one to test the consistency of independently measured absolute values of the mass attenuation coefficient with those obtained by the thickness transfer method; and it tests the linearity of the response of the counter and counting chain throughout the range of X-ray intensities encountered in a given experiment. In light of the results for gold, the strategy to be ideally employed in measuring absolute X-ray mass attenuation coefficients, X-ray absorption fine structure and related quantities is discussed. PMID:22338654

Radioactive materials are used in Jordan for peaceful applications in medicine, industry, agriculture, environmental science, education and research and military applications. Most of these radioactive sources used are imported, therefore trans-boundary movement is a significant factor in consideration of security measures during movement of these sources. After 11/9 2001 event, IAEA efforts began to focus and concentrate on security in transport of radioactive materials, after the emergence of risks of using these sources in terrorist activities. In 2002, Efforts were initiated by the IAEA to provide additional guidance for security in the transport of radioactive materials, based upon the new security requirements in the Recommendations on the Transport of Dangerous Goods. This paper reviews some of the measures relating to the transport of radioactive materials in Jordan

Radioactive ion beam is generally characterized by small beam intensity and big beam size. In order to carry on precise scattering and reaction experiments it is necessary to monitoring the incident angle and absolute number of the beam hitting the target. The authors therefore have designed and made up low pressure multiwire proportional chambers (LPMWPC) which have good beam transparency and are also adequate to be used in vacuum. Experiment test indicates that the position resolution of the chambers is about 0.5 mm and the position determination efficiency is larger than 90% for the low Z particles at intermediate energies. This kind of chamber can then be used to detect the direction of the incident particle and to record the absolute number of the particles which really hit the target, or to detect the emitting angle of the outgoing particles

Mass spectroscopy has the distinct advantage of detecting atoms rather than radioactive decay products for nuclides of low specific activity. Electrothermal vaporization (ETV) is an efficient means of introducing small volumes of prepared samples into an inductively coupled mass spectrometer to achieve the lowest absolute detection limits. The operational characteristics and capabilities of electrothermal vaporization inductively coupled mass spectrometer mass spectroscopy were evaluated. We describe its application as a detection method for determining Pu in urine, in conjunction with a preliminary separation technique to avoid matrix suppression of the signal.

The capability of performing accurate absolute measurements of neutron beam polarization opens a number of exciting opportunities in fundamental neutron physics and in neutron scattering. At the LANSCE pulsed neutron source we have measured the neutron beam polarization with an absolute accuracy of 0.3% in the neutron energy range from 40 meV to 10 eV using an optically pumped polarized sup 3 He spin filter and a relative transmission measurement technique. sup 3 He was polarized using the Rb spin-exchange method. We describe the measurement technique, present our results, and discuss some of the systematic effects associated with the method.

Since the pioneering works of Jakobson and Benedicks & Carleson and others, it has been known that a positive measure set of quadratic maps admit invariant probability measures absolutely continuous with respect to Lebesgue. These measures allow one to statistically predict the asymptotic fate of Lebesgue almost every initial condition. Estimating fluctuations of empirical distributions before they settle to equilibrium requires a fairly good control over large parts of the phase space. We use the sub-exponential slow recurrence condition of Benedicks & Carleson to build induced Markov maps of arbitrarily small scale and associated towers, to which the absolutely continuous measures can be lifted. These various lifts together enable us to obtain a control of recurrence that is sufficient to establish a level 2 large deviation principle, for the absolutely continuous measures. This result encompasses dynamics far from equilibrium, and thus significantly extends presently known local large deviations results for quadratic maps.

The pharmacokinetics, tissue distribution, and excretion of buagafuran (BF, 4-butyl-?-agarofuran), a promising antianxiety drug isolated from Gharu-wood (Aquilaria agallocha Roxb), were investigated in rats. BF plasma concentration was determined in rats after oral and intravenous doses by GC-TOF-MS. BF showed nonlinear pharmacokinetics after oral and intravenous administration of 4, 16, and 64 mg/kg. The AUC0-? and Cmax did not increase proportionally with doses, indicating the saturation in absorption kinetics of BF in rats after oral dosage. BF absorption was extremely poor with an absolute bioavailability below 9.5%. After oral administration of 3H-BF (4 mg/kg) to rats, radioactivity was well distributed to the tissues examined. The highest radioactivity was foun...

This book provides information on the following topics in the petroleum domain: Review of Fundamental Notions, General Processes used for Recording Physical Parameters, Generalities on Electrical Measurements, Resistivity Measurements, Conductivity Measurements, Electromagnetic Wave Propagation and Attenuation Measurements, Magnetic Susceptibility and Total Magnetic Field Measurements, Spontaneous Potential Measurement, Generalities on Nuclear Measurements, Generalities on Natural Radioactivity, Total Natural Radioactivity Measurements, Spectrometry of Natural Activity, Density and Photoelectric Index Measurements, Generalities on Neutron Physics, Neutron Porosity Measurements, Spectrometry of Induced Gamma Rays, Thermal Neutron Die-Away Measurements, Nuclear Magnetic Resonance Measurements, Generalities on Acoustic Measurements, Sonic Transit Time Measurements, Sonic Amplitude and Attenuation Measurements, Well Seismic Techniques, Generalities on Rock Texture and Structure Determination, Dip and Image Acquisition, Interpretation and Applications, Temperature Measurements, Borehole Caliper Measurements, Wire line Rock Sampling, Fluid Sampling and Pressure Measurements, Place and Role of Logging in Petroleum Exploration, Logging Programs and''Quick-look'' Methods. (author)

The purpose of this study was to test a patient-specific quality assurance (QA) protocol for intensity-modulated arc radiotherapy (IMAT), and to evaluate the use of an intensity-modulated stationary radiotherapy QA device (2D ion chamber array). Thirty-nine IMAT treatment plans for brain, spine, and prostate were analyzed using 3 methods: ion chamber (1D absolute, n=39), film (2D relative, coronal/sagittal, n=8), and 2D ion chamber array ("ICA," 2D absolute, coronal/sagittal, n=39) measurements. All measurements were compared to the treatment planning system (TPS) dose calculation with gamma analysis (3%, 3mm distance-to-agreement criteria) or absolute point dose comparison. The ICA measurements were also directly compared to film and ion chamber for validation. Absolute 1D measurements agreed well calculation (ion chamber: average deviation 1.4%, range -0.9% to 2.8%; ICA: average deviation 0.7%, range -1.8% to 2.9%). Relative 2D measurements also showed good agreement with calculation (>93% of pixels in all films passing gamma, >90% of pixels in all ICA measurements passing gamma). ICA and film relative dose results were highly similar (> 90% of pixels passing gamma in 94% of QAs). Coronal and sagittal ICA measurements were statistically indistinguishable by the paired t-test with a hypothesized mean difference of 0.2%. Ion chamber and ICA absolute dose measurements usually agreed well, but had disparities of 2-3% in 18% of plans. After validating the new IMAT implementation with ion chamber, film, and ICA, we reduced our QA from 5 (ion chamber, film, and ICA) to 2 measurements (ion chamber and single ICA) per plan. The ICA (Matrixx®, IBA Dosimetry) was validated in relative analysis mode, but ion chamber measurements are recommended for absolute dose comparison.

There are two further X spectrometer equipments: one K line hybrid X-fluorescence spectroscope with graphite monochromator. Their advantage is the direct nondestructive measurements of radioactive mix solutions without liquid waste generation.

were measured using a technique known as Surface Layer Activation (SLA). This diagnostic technique involves producing a radioactive tracer in a given surface by bombardment with high ..... precision is the uncertainty in the, half life of Tc~'~.

Jun 28, 2005 ... Loess deposits, composed of fine wind-blown dust produced by the grinding ... by measuring how much uranium, a radioactive element, has decayed. ... “In southeast Brazil, for example, winter rain comes from the nearby ...

This document provides a transcript of an interview with John W. Healy concerning his recollections of measuring radioactive effluents at Hanford. Included are comments concerning the `Green Run`, other radioiodine releases, and a release of radioruthenium.

This article reviews the basis of PET imaging and current applications to cardiology. Included is a discussion of physical principles, detectors, quantitative estimation of regional radioactivity concentrations, radiopharmaceuticals, and application to flow and metabolism measurements in the myocardium.

Doses occuring in nondestructive investigation with sealed radioactive sources were measured with thermoluminiscent dosimeters. By no means, the limits given by law were achieved. So, no additional radiation protection effort is necessary. (orig.)

Measurements and Analysis of the Stable and Radioactive Isotopic Compositions of Long-lived ... that control the composition of the tropical transition layer, and the sources and sinks of these greenhouse gases. ... Last Activity: Dec 10, 2010 ...

... November Newsletter . NAS to Study Cancer Risks Near Nuclear Facilities . Summer School Announcement Upcoming Events . NRC Meeting Webcasts - ... Instrumentation and Measurements • Lasers • Medical and Dental Equipment/Shielding • Medical and ... Accidents • Nuclear Medicine Patient Issues • Nuclear or Radioactive ...

Potential application of the Radiomatic 150TR Flow Scintillation Analyzer (Packard Instrument Co., USA) for measuring low radioactivity of tritium-labelled amino acids in eluate from the Amino Acid Analyzer 835 (Hitachi, Japan) was studied. Six scintillating cocktails were tested and the Hionic-Fluor and Ultima-Flo AP cocktails proved the most appropriate for flow measurement of radioactivity. Efficiency of tritium radioactivity recording under various conditions of analysis was determined. Under optimal conditions the lower detection limit for the Hionic-Fluor was 150, while for Ultima-Flo AP-100 decays/min in the peak of amino acid

The report deals with 1. operation of SE (general aspects, maintenance, recurring tests, peculiarities); 2. monitoring of operation (temperature measurement, measurement of humidity, ventilation condensate, sump monitoring); 3. radiological data (personnel surveillance, aerosal activitiy, radioactive release with circulating and waste air, radioactive release via the waste water path, radon monitoring in SE, control of surroundings, radioactive wastes). (orig.). [Deutsch] Der Bericht enthaelt: 1. Betrieb SE (Allgemeines, Wartungsarbeiten, wiederkehrende Pruefungen, Besonderheiten): 2. Betriebsueberwachung (Temperaturmessung, Feuchtigkeitsmessung, Lueftungskondensat, Sumpfueberwachung); 3. Radiologische Daten (Personenueberwachung, Aerosolaktivitaet, Aktivitaetsabgabe mit Umluft und Fortluft, Aktivitaetsabgaben ueber den Abwasserpfad, Radonueberwachung im SE, Umgebungsueberwachung, radioaktive Abfaelle). (orig.).

Developmental control of protein synthesis in the postnatal growth of the lung has not been systematically studied. In male Fischer 344 rats, lung growth continues linearly as a function of body weight (from 75 to 450 g body weight). To study total protein synthesis in lungs of growing rats, we used the technique of constant intravenous infusion of tritiated leucine, an essential amino acid. Lungs of sacrificed animals were used to determine the leucine incorporation rate into newly synthesized protein. The specific radioactivity of the leucine associated with tRNA extracted from the same lungs served as an absolute index of the precursor leucine pool used for lung protein synthesis. On the basis of these measurements, we were able to calculate the fractional synthesis rate (the proportion of total protein destroyed and replaced each day) of pulmonary proteins for each rat. Under the conditions of isotope infusion, leucyl-tRNA very rapidly equilibrates with free leucine of the plasma and of the extracellular space of the lung. Infusions lasting 30 minutes or less yielded linear rates of protein synthesis without evidence of contamination of lung proteins by newly labeled intravascular albumin. The fractional synthesis rate is considerably higher in juvenile animals (55% per day) than in adult rats (20% per day). After approximately 12 weeks of age, the fractional synthesis rate remains extremely constant in spite of continued slow growth of the lung. It is apparent from these data that in both young and adult rats the bulk of total protein synthesis is devoted to rapidly turning over proteins and that less than 4 percent of newly made protein is committed to tissue growth.

The content of radiation-induced defects (RIDs) in kaolinite samples originating from lateritic soils and continental detritic sediments of the middle Amazon Basin (Brazil) is investigated using electron paramagnetic resonance. The paleodose registered by kaolinites ranges from 80 to 900 kGy. Present-day dose rates of radiation, determined from the whole-rock U and Th content, range between 4000 and 40,000 mGy/ka. In most samples, U and Th concentrations are correlated, suggesting that U has not been remobilized by lateritization. This observation is consistent with the fact that ˜80% of the total U content is incorporated in resistant minerals, such as zircon and Ti oxides. The heterogeneous distribution of U, observed by induced fission tracks mapping, makes it possible to neglect the ?-radiation contribution of the U decay chains in the dose-rate calculation. The interpretation of the measured content of RIDs in kaolinite is then performed using the calculated present-day dose rate and assuming equilibrium in the radioactive decay chains. For the sedimentary samples, the amount of RIDs is broadly correlated to the dose rate and provides apparent absolute ages older than 20 Ma. The RID contents in kaolinites from the lateritic soils provide apparent ages ranging from 10 to 6 Ma. The high RID content of these lateritic kaolinites shows that their chemical, isotopic, and crystallographic properties are not representative of present-day weathering conditions. Models assuming the “dynamical equilibrium” of kaolinites with local physical-chemical conditions prevailing in lateritic soils are thus questionable. Alternatively, our findings bring strong support for the use of the isotopic composition of kaolinites to decipher continental paleo-climates.

Korea is confronting a serious social conflict, which is phenomenon of local residents reaction to radioactive waste disposal facility. This phenomenon is traced back to the reason that the project sponsors and local residents do not communicate sufficiently each other. Accordingly, in order to overcome local residents` reaction to radioactive waste disposal facility siting effectively, it is absolutely necessary to consider the way of solutions and strategies with regard to obstacle factors for public communication. In this content, this study will review three cases (An-myon Island, Gul-up Island, Yang-yang) on local residents reaction to facility siting. As a result of analysis, authoritarian behavior of project sponsors, local stigma, risk, antinuclear activities of environmental group, failures in siting the radioactive waste disposal facility, etc. has negative impact on public communication of the radioactive waste disposal facility siting. In this study, 5 strategies (reform of project sponsor`s authoritarianism, incentive offer, strengthening PA activities, more active talks with environmental groups, promoting credibility of project sponsors) arc suggested to cope with obstacle factors of public communication.

Natural and man-made radioactivities in the environment have been extensively researched in the second half of this century. Recently, increased attention has been given to (1) radioactive waste willfully placed in the environment by discharges from nuclear reprocessing plants or by dumping at sea, and (2) radioactive materials lost due to accidents in terrestrial (civilian power) or marine (submarine propulsion) reactors. Increasing field measurements, and disclosures of dumping and accidents in the former Soviet Union, are adding greatly to the knowledge of environmental radioactivity. New, more powerful computers are having a double impact. They make possible Geographical Information Systems for geo-referencing and correlating multi-variable datasets. Furthermore, supercomputers enable global atmospheric, oceanographic and terrestrial circulation and transport models, which include physical, chemical and biological processes. We will review exemplary work on the sources, transport, disposition and impact of anthropogenic environmental radioactivity. Such work both provides new knowledge of environmental processes and furnishes the basis for deciding on potential remediation actions.

Optical frequency comparison of the 40Ca+ clock transition ?Ca (2S1/2-2D5/2, 729nm) against the 87Sr optical lattice clock transition ?Sr (1S0-3P0, 698nm) has resulted in a frequency ratio ?Ca / ?Sr = 0.957 631 202 358 049 9(2 3). The rapid nature of optical comparison allowed the statistical uncertainty of frequency ratio ?Ca / ?Sr to reach 1 × 10-15 in 1000s and yielded a value consistent with that calculated from separate absolute frequency measurements of ?Ca using the International Atomic Time (TAI) link. The total uncertainty of the frequency ratio using optical comparison (free from microwave link uncertainties) is smaller than that obtained using absolute frequency measurement, demonstrating the advantage of optical frequency evaluation. We note that the absolute frequency of 40Ca+ we measure deviates from other published values by more than three times our measurement uncertainty. PMID:23037353

Experimental apparatus and procedure for measurements of absolute total (apparent and counting) and relative partial cross sections for ionization of atoms by electron impact are described in some detail, and results on Ba and Eu atom are reported. A crossed electron-atom beam ion source combined with a 60° sector mass analyzer has been used to measure the partial cross sections. For the measurement of the absolute total cross sections, another type of crossed electron-atom beam arrangement combined with a time-of-flight (TOF) velocity measurements of target atoms has been used. The absolute cross sections have been determined with experimental accuracy of ± 23%, and have been used to calibrate the partial cross-sections. The results of Ba atom agree well with previously reported results. The Eu+ cross section curve shows remarkable peak structure near the 4f ionization thresholds, probably attributed to the resonance excitation of 4f 66s2nl aoutoionization states via temporal negative-ion formation.   

The improvement in the nuclear industry makes that it is important to protect personnel and equipment form radiation, because they have many chance to treat radioactive material. The head office on a prevention and an emergency measure for a radioactive release is necessary. In this study, display device for radioactive information using wireless communication has been developed to display a radioactivity using radio frequency modem. Therefore, the unlocated head office can be operated in a portable environment using a notebook PC or a compact display device. Korea Atomic Energy Research Institute,which runs a research reactor, HANARO, needs the head office on a prevention and an emergency measure for a radioactive release. The display device for radioactive information using wireless communication to be developed in this study, can be used to the head office as a display device not to pay additional cost. This study has developed the display device for radioactive information using wireless communication, Remote Radiation Display System(RRDS), which transmits every 10 second a radioactive information to be displayed to RMT(Radiation Monitoring Terminal) of Radiation Monitoring System in HANARO. In this study, first, a configuration of hardware and software in HANARO RMS has been reviewed. Second, a RS-2322C serial communication program to transmit a radioactive information in HARARO RMS to RRDS using radio frequency modem has been developed. Finally, a RS-2322C serial communication program to receive a radioactive information in HANARO RMS from RRDS using radio frequency modem and GUI program to display the received information to RRDS has been developed. (author). 19 refs., 3 tabs., 25 figs.

The authors examine the subsonic plasma jet obtained in a hightemperature gasdynamic apparatus type VGU-2. The power was checked on the plate circuit of the vacuum-tube generator and was kept constant at 31.6 kW at all pressures. Two complimentary methods were used: photographic (recording, spectrum identification, and absolute intensity measurement) and photoelectric (absolute intensity measurement). Temperature measurements are reported for a subsonic free air-plasma jet derived from the VGU-2 plasmatron in the pressure range 5 X 10/sup 3/less than or equal toPless than or equal to10/sup 5/ Pa.

We study the relationship between Amoeba forcing (the partial order which generically adds a measure one set of random reals) and projective measurability. Given a universe V of set theory and a forcing notion P in V we say that V is Sigma^1_n - P - absolute iff for every Sigma^1_n-sentence phi with parameters in V we have V models phi iff V^P models phi. We show that Sigma^1_4-Amoeba-absoluteness implies that forall a in omega^omega (omega_1^{L[a]} < omega_1^V), and hence Sigma^1_3-measurability. This answers a question of Haim Judah (private communication).

The present paper describes the development of a radon standard source for use in establishing the traceability of radon concentration measurements in air. Previously, radon generated by bubbling air through a radium salt solution was widely used for calibration of radon measurement equipment; however, the handling of a solid-phase radon source is easier. In the present study, the radioactivity of radon released in a vapor phase was determined from the difference between the radioactivity of the radium and the residual radon progenies in the source. A germanium detector, calibrated using gamma reference sources, was used for these radioactivity measurements. Under equilibrium conditions the radioactivity of the radon released from the radium source was found to be 988 Bq. The source was sealed in a stainless-steel container having a nominal capacity of 6 l to produce a radon standard source of density of 167.5 [Bq/l].

The objectives of the project are to monitor an abnormal radiation level in Taegu and Kyungpook region, and to enhance our ability to prepare for the radiological emergency situation by establishing the radioactivity monitoring system in Taegu and Kyungpook region. Gross beta activities were measured and gamma radionuclides were analysed for the environmental samples of air-borned dust. precipitation. fallout and drinking water collected in Taegu radioactivity monitoring center. and gamma exposure rates were also measured. To establish the basic data base on the environmental radioactivity, gamma radionuclide analyses were carried out for the samples of soil, drinking water, grain, vegetable, milk, and fish which were obtained from 31 different areas, and the spatial gamma exposure rates from 61 different points were also measured in Taegu and Kyungpook region. In conclusion, it didn't appear any evidence for newly pollution of artificial radioactivity in Taegu and Kyungpook region.

Following a radioactive fallout event, there are a number of possible intervention measures to reduce radioactive doses to the public via the surface water pathway. We have critically reviewed the options available to decision-makers in the event of radioactive contamination of surface waters. We believe that the most effective and viable measures to reduce radioactivity in drinking water are those which operate at the water treatment and distribution stage. Intervention measures to reduce concentrations of radioactivity in rivers and reservoirs are expected to be much less viable and efficient at reducing doses via the drinking water pathway. Bans on consumption of freshwater fish can be effective, but there are few viable measures to reduce radioactivity in fish prior to the preparation stage. Lake liming and biomanipulation have been found to be ineffective for radiocaesium, although the addition of potassium to lakewaters appears promising in some situations. Lake liming may be effective in reducing radiostrontium in fish, though this has not, to our knowledge, been tested. De-boning fish contaminated by strontium is probably the most effective food preparation measure, but salting and freezing can also reduce radiocaesium concentrations in fish. The provision of accurate information to the public is highlighted as a key element of countermeasure implementation. PMID:11446114

We present an experimental approach using magnetic force microscopy for measurements of the absolute value of the magnetic penetration depth ? in superconductors. ? is obtained in a simple and robust way without introducing any tip modeling procedure via direct comparison of the Meissner response curves for a material of interest to those measured for a reference sample. Using a well-characterized Nb film as a reference, we determine the absolute value of ? in a Ba(Fe0.92Co0.08)2As2 single crystal and a MgB2 thin film through a comparative experiment. Our apparatus features simultaneous loading of multiple samples, and allows straightforward measurement of the absolute value of ? in superconducting thin film or single-crystal samples.

Measurements of thermophysical properties of the (water + lithium bromide + lithium iodide + lithium chloride) system (LiBr:LiI:LiCl = 4.5:1:2 by mole ratio) were performed as functions of concentration and temperature. Solubilities were measured by a visual polythermal method at temperatures from (248.59 to 350.46) K. Regression equations were obtained with a least-squares method, and the average absolute deviations of the calculated values from the experimental data were 0.10% (solution temperature Antoine-type equation. The average absolute deviation of the calculated values from the experimental data was 1.83%. Densities and viscosities were measured at concentrations from (50.0 to 64.0) mass % and temperatures from (283.15 to 333.15) K. Regression equations for densities and viscosities were obtained with a least-squares method, and the average absolute deviations of the calculated values from the experimental data were 0.08% and 0.87%, respectively.

Previous studies on protein turnover in /sup 3/H-labelled L-cell cultures have shown recovery of total /sup 3/H at the end of a three-day experiment to be always significantly in excess of the /sup 3/H recovered at the beginning of the experiment. A number of possible sources for this error in measuring radioactivity in cell proteins has been reviewed. /sup 3/H-labelled proteins, when dissolved in NaOH and counted for radioactivity in a liquid-scintillation spectrometer, showed losses of 30-40% of the radioactivity; neither external or internal standardization compensated for this loss. Hydrolysis of these proteins with either Pronase or concentrated HCl significantly increased the measured radioactivity. In addition, 5-10% of the cell protein is left on the plastic culture dish when cells are recovered in phosphate-buffered saline. Furthermore, this surface-adherent protein, after pulse labelling, contains proteins of high radioactivity that turn over rapidly and make a major contribution to the accumulating radioactivity in the medium. These combined errors can account for up to 60% of the total radioactivity in the cell culture. Similar analytical errors have been found in studies of other cell cultures. The effect of these analytical errors on estimates of protein turnover in cell cultures is discussed.

This paper discusses the following topics: pp elastic absolute cross section measurement; spin transfer measurements in np elastic scattering; single pion production in np scattering; photoproduction of high P{sub t} jets in the wide band beam of the tevatron; and search for K{sub L}{sup 0} {yields} {mu}e, K{sub L}{sup 0} {yields} ee.

Because of their low neutron sensitivity Geiger-Mueller counters are often used in mixed-field dosimetry to determine the photon dose fraction. The associated-particle technique has been used to determine absolutely the neutron sensitivity of an energy-compensated ZP1320 Geiger-Mueller counter at 3 MeV. The measurement is consistent with previous measurements using this type of counter.

Because of their low neutron sensitivity Geiger-Müller counters are often used in mixed-field dosimetry to determine the photon dose fraction. The associated-particle technique has been used to determine absolutely the neutron sensitivity of an energy-compensated ZP1320 Geiger-Müller counter at 3 MeV. The measurement is consistent with previous measurements using this type of counter. PMID:7152933

The goal of this work is an evaluation of utmost precision and analysis of any possible errors and corrections in planned experiment of new mass measurement of J/psi and psi' mesons on VEPP-4M collider with absolute energy calibration by the spin precession frequency measurements.

This work presents the different measurement possibilities of the SOLEX facility for the characterization of an energy-dispersive detector. We first describe the SOLEX apparatus, its energy range and the internal proportional counter used for absolute flux measurement then we give an example of an energy-dispersive detector characterization.

The recent measurement of negative higher-order Kerr effect (HOKE) terms in gases has given rise to a controversial debate, fed by its impact on short laser pulse propagation. By comparing the experimentally measured yield of the third and fifth harmonics, with both an analytical and a full comprehensive numerical propagation model, we confirm the absolute and relative values of the reported HOKE indices.

A multicharged ion-atom merged-beams apparatus has been used in conjunction with the ORNL-ECR ion source to measure accurate absolute electron-capture cross sections in the energy range from below 1 eV/amu to 1500 eV/amu. Measurements for N3+,4+,5+ + H(D) collisions indicate good agreement with avai...

In this study, absorbed doses were measured and compared for high-energy electrons (6, 9, 12, 16, and 20 MeV) using International Atomic Energy Agency (IAEA), Technical Reports Series No. 277 (TRS), TRS 381, and TRS 398 dosimetry protocols. Absolute dose measurements were carried out using FC65-G Fa...

Radioactive material package designers use structural testing to verify and demonstrate package performance. A major part of evaluating structural response is the collection of reliable instrumentation measurement data. Over the last four decades, Sandia National Laboratories (SNL) has been actively involved in the development, testing, and evaluation of measurement devices for a broad range of applications, resulting in the commercialization of several measurement devices commonly used today. SNL maintains an ongoing program sponsored by the US Department of Energy (DOE) to develop and evaluate measurement devices to support testing of packages used to transport radioactive or hazardous materials. The development of the enhanced strain measurement device is part of this program.

Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. Using data taken in 2010, LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In addition to the classic ``van der Meer scan'' method a novel technique has been developed which makes use of direct imaging of the individual beams using beam-gas and beam-beam interactions. This beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. The results of the two methods have comparable precision and are in good agreement. Combining the two methods, an overal precision of 3.5% in the absolute luminosity determination is reached. The techniques used to transport the absolute luminosity calibration to the full 2010 data-taking period are presented.

Fourth-stadium nymphs of the brown-winged green bug, Plautia stali, were orally labeled with [35S]cysteine. We then measured the levels of radioactivity in the fourth- and last-stadia exuvia. Levels of radioactivity in the exuvia increased with increasing doses of [35S]cysteine. The radioactivity levels of labeled exuvia treated with KOH suggested that the [35S]cysteine was incorporated into cuticular proteins. The degradation pattern of labeled exuvia by bovine pancreas protease and crude enzyme solutions prepared from entomopathogenic fungi suggested that radiolabeled exuvium can be used as a substrate for cuticle-degrading enzymes.   

This patent describes an improvement in a process for diagnosing myasthenia gravis. The process comprises the steps of preparing a complex of acetycholine receptor protein, toxin and a radioactive isotope, incubating the complex with a serum sample from a patient so as to join antibodies engendered in connection with myasthenia gravis to the complex, precipitating the complex joined with antibody with anti-immunoglobulin and measuring radioactivity, from the radioactive isotope, of the precipitated complex. The improvement is that the acetylcholine receptor protein is derived from cells of the TE671 Line.

A multicusp source for positive ion beams has been designed and constructed in collaboration with the Ion Beam Technology Department of LBNL for the TRIUMF ISAC project. This type of source has demonstrated a high yield of singly charged ions, a low energy spread, a good emittance and is compact and simple. Several stages of tests and measurements using non-radioactive beams to characterize the source performance are being carried out both at LBNL and at TRIUMF prior to the final phase of radioactive target-source system tests. Results of these non-radioactive tests and certain problems encountered are reported and discussed in this paper. (author)

Because atmospheric longwave radiation is one of the most fundamental elements of an expected climate change, there has been a strong interest in improving measurements and model calculations in recent years. Important questions are how reliable and consistent are atmospheric longwave radiation measurements and calculations and what are the uncertainties? The First International Pyrgeometer and Absolute Sky-scanning Radiometer Comparison, which was held at the Atmospheric Radiation Measurement program's Souther Great Plains site in Oklahoma, answers these questions at least for midlatitude summer conditions and reflects the state of the art for atmospheric longwave radiation measurements and calculations. The 15 participating pyrgeometers were all calibration-traced standard instruments chosen from a broad international community. Two new chopped pyrgeometers also took part in the comparison. And absolute sky-scanning radiometer (ASR), which includes a pyroelectric detector and a reference blackbody source, was used for the first time as a reference standard instrument to field calibrate pyrgeometers during clear-sky nighttime measurements. Owner-provided and uniformly determined blackbody calibration factors were compared. Remarkable improvements and higher pyrgeometer precision were achieved with field calibration factors. Results of nighttime and daytime pyrgeometer precision and absolute uncertainty are presented for eight consecutive days of measurements, during which period downward longwave irradiance varied between 260 and 420 W m-2. Comparisons between pyrgeometers and the absolute ASR, the atmospheric emitted radiance interferometer, and radiative transfer models LBLRTM and MODTRAN show a surprisingly good agreement of <2 W m-2 for nighttime atmospheric longwave irradiance measurements and calculations.

We have measured the absolute and coupled system responsivities of several image intensifier types at several wavelengths in the visible spectrum. Intensifiers characterized include microchannel plate (MCP) generation II proximity-focused and hybrid generation I/generation II electrostatic-focused designs. Configurations including single plate, double plate, nominal and high strip current MCPs, and standard S20 and super generation II enhanced S-20 photocathodes were evaluated. Absolute responsivity measurements were performed using NIST-traceable radiometry instrumentation. The normalized relative sensitivities and overall optical luminous gain performance provided by individual intensifiers when similarly coupled to either high resolution 10-bit RS-170 CCD or FPS cameras are presented along with their radiometric data.

We have developed a measurement method for obtaining spatial distributions of absolute densities of CF and CF2 radicals in a plasma reactor by combining single-path infrared laser absorption spectroscopy (IRLAS) and laser-induced fluorescence (LIF) techniques. This novel method has been successfully applied to the spatial distribution measurement of absolute densities of CF and CF2 radicals in an electron cyclotron resonance (ECR) plasma reactor employing a tetrafluorocarbon gas (C4F8). It was found that CF radical densities were higher than CF2 ones in the plasma region but lower outside the plasma region.   

We use the three-cornered-hat method to evaluate the absolute frequency stabilities of three different ultrastable reference cavities, one of which has a vibration-insensitive design that does not even require vibration isolation. An Nd:YAG laser and a diode laser are implemented as light sources. We observe $\\sim1$ Hz beat note linewidths between all three cavities. The measurement demonstrates that the vibration-insensitive cavity has a good frequency stability over the entire measurement time from 100 $\\mu$s to 200 s. An absolute, correlation-removed Allan deviation of $1.4\\times10^{-15}$ at 1 s of this cavity is obtained, giving a frequency uncertainty of only 0.44 Hz.

Using data collected at the {psi}(3770) resonance with the CLEO-c detector at the Cornell e{sup +}e{sup -} storage ring, we present improved measurements of the absolute branching fractions of D{sup +} decays to K{sup 0}e{sup +}{nu}{sub e}, {pi}{sup 0}e{sup +}{nu}{sub e}, K*{sup 0}e{sup +}{nu}{sub e}, and {rho}{sup 0}e{sup +}{nu}{sub e}, and the first observation and absolute branching fraction measurement of D{sup +}{yields}{omega}e{sup +}{nu}{sub e}. We also report the most precise tests to date of isospin invariance in semileptonic D{sup 0} and D{sup +} decays.

Using data collected at the psi(3770) resonance with the CLEO-c detector at the Cornell e+e- storage ring, we present improved measurements of the absolute branching fractions of D+decays to K0e+ve, pi0e+ve, K*0e+ve, and p0e+ve, and the first observation and absolute branching fraction measurement of D+ --> omega e+ve. We also report the most precise tests to date of isospin invariance in semileptonic D0 and D+ decays. PMID:16383892

A new type of two-wavelength interferometer for the measurement of absolute distance is described. Since the wavelength of the laser diode is temporally multiplexed, only one laser diode light-source is required, thus eliminating the necessity of aligning two independent optical axes. Absolute distance is calculated from the difference of the phases in the interference signals generated by each wavelength. The self-correlation function is applicable in our system for detecting this phase- difference between two kinds of interference signals, thereby, the signal processing is very simple and there is a possibility that the real-time distance measurement becomes possible in our new method.

Radioactivity of /sup 67/Ga in the paw edema and the edema rate were measured after subcutaneous injection of histamine into the paw of the conscious rat. The radioactivity increased almost parallel with the edema rate following the injection of histamine. The increase in the radioactivity and edema were almost completely prevented by pretreatment with a 10 mg/kg dose of chlorpheniramine, an antihistaminic agent. A good correlation between the edema rate and the radioactivity was demonstrated. These results suggest that /sup 67/Ga-citrate is useful for monitoring the process of acute inflammation in the pharmacological evaluation of anti inflammatory drugs. Moreover, there is also a possibility that /sup 67/Ga-citrate may be useful in measuring vascular permeability.

Results of radioactivity measurements in the environment in the Netherlands carried out by RIZA, RIKZ, Inspectorate for Health Protection and Veterinary Public Health and RIVM in 1999, are presented. Radioactivity was measured for airborne particulate, deposition, surface water, seawater and water for human consumption. Results for ambient dose equivalent rates were obtained from the National Radioactivity Monitoring Network. In 1999 there were no elevated levels of radioactivity found in the environment in the Netherlands. [Dutch] De resultaten van radioactiviteitsmetingen in het milieu in Nederland verricht door RIZA, RIKZ, Keuringsdienst van Waren en RIVM in 1999 worden gepresenteerd. Radioactiviteit werd gemeten in luchtstof, depositie, zoet water, zeewater en drinkwater. Metingen van het omgevingsdosisequivalenttempo zijn gedaan met het Nationaal Meetnet Radioactiviteit. In 1999 zijn geen verhogingen van radioactiviteit in het milieu in Nederland gevonden.

Knowledge of the rheology of the radioactive sludge slurries at the Savannah River Site (SRS) is necessary in order to ensure that they can be retrieved from waste tanks and processed for final disposal. At Savannah River Site (SRS), Tank 42 sludge represents one of the first HLW radioactive sludges to be vitrified in the Defense Waste Processing Facility (DWPF). The rheological properties of unwashed Tank 42 sludge slurries at various solids concentrations were measured remotely in the Shielded Cells at the Savannah River Technology Center (SRTC) using a modified Haake Rotovisco viscometer. Rheological properties of Tank 42 radioactive sludge were measured as a function of weight percent total solids to ensure that the first DWPF radioactive sludge batch can be pumped and processed in the DWPF with the current design bases. The yield stress and consistency of the sludge slurries were determined by assuming a Bingham plastic fluid model.

There are different ways to calculate the absolute delayed neutron yields. In this work, we use two methods. The first one consists in estimating the absolute delayed neutron yields by NJOY nuclear data processing system. This treatment requires data coming from general purpose files of various libraries (Endf, Jeff,...). In the second one, the summation calculation is used to perform the evaluation of absolute delayed neutron yields. For this case, the data used are the delayed neutron branching ratios, also called delayed neutron emission probabilities, and cumulative fission yields. These data are found in the Radioactive Decay Data and Fission Yield Data files (File 8). Finally, the results obtained by both methods will be compared to experimental values proposed by Tuttle, Waldo and Benedetti. Except for Pu{sup 242} and some minor fissile nuclides (Pa{sup 231}, Np{sup 237} and Np{sup 238}), the total neutron yields estimated by NJOY processing show a good agreement between calculation and experiments. The summation calculations show some discrepancies for the isotopes U{sup 233}, U{sup 234}, U{sup 235}, U{sup 238}, Pu{sup 238}, Pu{sup 241}, Pu{sup 242}, Am{sup 241}, Cm{sup 245} and Cf{sup 252}

The patented VAC*TRAX process was designed in response to the need to remove organic constituents from mixed waste, waste that contains both a hazardous (RCRA or TSCA regulated) component and a radioactive component. Separation of the mixed waste into its hazardous and radioactive components allows for ultimate disposal of the material at existing, permitted facilities. The VAC*TRAX technology consists of a jacketed vacuum dryer followed by a condensing train. Solids are placed in the dryer and indirectly heated to temperatures as high as 260{degrees}C, while a strong vacuum (down to 50 mm Hg absolute pressure) is applied to the system and the dryer is purged with a nitrogen carrier gas. The organic contaminants in the solids are thermally desorbed, swept up in the carrier gas and into the condensing train where they are cooled and recovered. The dryer is fitted with a filtration system that keeps the radioactive constituents from migrating to the condensate. As such, the waste is separated into hazardous liquid and radioactive solid components, allowing for disposal of these streams at a permitted incinerator or a radioactive materials landfill, respectively. The VAC*TRAX system is designed to be highly mobile, while minimizing the operational costs with a simple, robust process. These factors allow for treatment of small waste streams at a reasonable cost. This paper describes the VAC*TRAX thermal desorption process, as well as results from the pilot testing program. Also, the design and application of the full-scale treatment system is presented. Materials tested to date include spiked soil and debris, power plant trash and sludge contaminated with solvents, PCB contaminated soil, solvent-contaminated uranium mill-tailings, and solvent and PCB-contaminated sludge and trash. Over 70 test runs have been performed using the pilot VAC*TRAX system, with more than 80% of the tests using mixed waste as the feed material.

The initiation to radioactivity can be aimed at adolescents to sensitive them to radiation field and to allow them to fabricate a pertinent opinion about the use of nuclear energy. The pupils of the third form of grammar school make a research on radioactivity and the different kind of radiations. The pupils participate to the measurement of the radiation emitted by the radon daughter and find the usual experimental protocol. (N.C.)

On the basis of measurement of total ..beta..- and ..gamma..-activity of rocks, mineral depositions and zones of present outflows of vapour-gas jets on the thermal field of caldera of Uzon volcano a material testifying to the elevated radioactivity of local sections with newly deposited sulphur is obtained. A supposition is made on the existence of newly formed sulphur of ephemeral radioactive compounds on the surface of new formations.

This paper covers the radioactive waste management policy and regulatory framework, the characteristics of low and intermediate level radioactive waste, the characteristics of waste package, the waste acceptance criteria, the waste acceptance and related activities, the design of the disposal system, the organization of waste transportation, the operation feature, the safety assessment of the Centre de L`Aube, the post closure measures, the closure of the Centre de la Mache disposal facility, the licensing issues. 3 tabs., 7 figs.

Experiences of an exercise with hazardous goods, in particular with radioactive substances (measurements and taking environmental samples) are described. Several special-purpose vehicles with equipment and specially trained crews were used together with radiation protection experts according to the concept of Hesse. It has been the greatest exercise in Hesse with regard to hazardous goods and in particular with regard to ''incidents with radioactive substances''. (orig.)

The radioactive sources are useful in several areas: medicine, research, measurement laboratories. Severe accidents in the past (Forbach in France 1991, Arequipa, Peru 1999, Goiania, Brazil 1987) remind us of the dangerous character of ionizing radiations. That is why the the management of radioactive sources are so regulated. Radiation protection and legal aspects of sealed and unsealed sources management are evoked, as well as the different official organisms that take a part in their management. (N.C.)

PurposeTo explore an effective and efficient end-to-end patient-specific quality-assurance (QA) protocol for volumetric modulated arc radiotherapy (VMAT) and to evaluate the suitability of a stationary radiotherapy QA device (two-dimensional [2D] ion chamber array) for VMAT QA. Methods and MaterialsThree methods were used to analyze 39 VMAT treatment plans for brain, spine, and prostate: ion chamber (one-dimensional absolute, n = 39), film (2D relative, coronal/sagittal, n = 8), and 2D ion chamber array (ICA, 2D absolute, coronal/sagittal, n = 39) measurements. All measurements were compared with the treatment planning system dose calculation either via gamma analysis (3%, 3- to 4-mm distance-to-agreement criteria) or absolute point dose comparison. The film and ion chamber results were si...

Absolute concentration profiles of S{sub 2} and OH in a premixed propane/air/SO{sub 2} flame at atmospheric pressure are determined by DFWM and absorption spectroscopy in the wavelength range from 308.5 to 310.5 nm. Relative concentrations of OH and S{sub 2} are mapped by taking advantage of the high sensitivity of the DFWM technique. Absorption spectroscopy, on the other hand, is used to obtain an absolute number density of OH at a position in the flame where a significant level of the hydroxyl radical occurs. These measurements are linked to the relative profiles and yield the absolute concentrations of the hydroxyl and sulfur dimer as a function of height above the burner surface. The measured profiles of S{sub 2} and OH are in good qualitative agreement with a recent theoretical model of the sulfur chemistry in flames. (author) 3 figs., 4 refs.

This report discusses the absolute neutron flux and neutron damage parameters in the steel walls of Hanford Site Waste Tank 101 SY at Richland, Washington which, were determined to ascertain if significant neutron radiation damage had occurred from the storage of radioactive waste. The tank had been in operation for many years. The tank contains actinides of various species and other radioactive material in various concentrations in approximately 1 million gal. of waste sludge. Because the tank obviously is not, and has not been critical, any neutron flux in the tank must be the result of the neutron sources in the tank and their multiplication through fission of the fissionable material present in the tank. There are six possible sources of neutrons in the tank. They are: (alpha,n) reactions, spontaneous fission, (gamma,n) reactions, cosmic rays, delayed neutrons and the fission process itself. In these calculations, we made conservative estimates of the amounts of radioactive isotopes that result in alpha decay, gamma production, and spontaneous fission in order to calculate the neutron source from these processes. Cosmic rays and delayed neutrons as a neutron source were also considered. A conservative estimate of the neutron sources was necessary because the contents and history of the tank are not well known. This neutron source was used in a neutron transport calculation to determine the multiplication resulting from actinide fission and the subsequent neutron fluxes. The absolute flux was used to determine the radiation damage parameters of helium production, hydrogen production, and displacement per atom in the wall of the tank.

The March 11, 2011 magnitude 9.0 Tohoku, Japan earthquake produced a tsunami that inundated the Fukushima Dai-ichi nuclear power plant and led to the accidental release of radioactive 131I, 132Te, 134Cs, and 137Cs to the atmosphere. The Japanese Nuclear Safety Commission estimates that 12,000 TBq of 137Cs were released to the atmosphere during the incident, which represents ~14% of the total estimated 137Cs emission from the Chernobyl disaster in April 1986. Measurements of airborne radiation collected at the Fukushima plant illustrate that >50% of the total emitted radiation was released on March 15 and 16 associated with explosions and fires at reactor units 1, 2, and 4, and 70% was emitted in the first 5 days of the event. The source of the radiation is thus well constrained in time and space, providing an opportunity to better understand long-range atmospheric transport processes from Asia to the Arctic, while also assessing the magnitude of the fallout in the Arctic. Here we describe the 137Cs and 134Cs fallout flux near Thule, Greenland (1700 m a.s.l.), at Summit (3200 m a.s.l.), Greenland, and within Denali National Park, Alaska (2400-3900 m a.s.l.) based on series of large-volume (5-15 l) snow pit samples collected in June and July, 2011. In addition to assessing the spatial variability of Fukushima fallout in the Arctic, the elevation range of samples allows for an analysis of any vertical heterogeneity in fallout transport and deposition. Major ion concentrations and stable water isotope ratios are used to confirm the seasonal timing of the Fukushima fallout horizon in the snowpack. Radiocesium was concentrated and isolated from the snow pit meltwater using the well-established ammonium phosphomolybdate (AMP) adsorption method, and 134Cs and 137Cs concentrations were measured using gamma spectrometry with a Canberra 3523 well-type intrinsic Ge-detector at the Dartmouth College Short-Lived Isotope Laboratory. NOAA HYPLIT atmospheric forward-trajectory model results are integrated with the radiocesium flux measurements and emission estimates to investigate long-range atmospheric transport paths and mechanisms. Furthermore, we evaluate the potential to use the Fukushima fallout horizon as an absolute time marker in future Arctic ice core studies.

The determination of concentrations of natural radioactivity in public water supplies begins with the measurement of the gross alpha particle activity. The gross alpha activity measurement is used as a screening technique. The gross alpha particle activity measurement may be su...

Bisphenol-A polycarbonates have a high absorption ability for noble gases that can be employed for sampling and measurement of radioactive isotopes of these gases. In this report the solubility of krypton, xenon and radon in the specified polycarbonates is determined by measurement of 85Kr, 133Xe and 222Rn absorbed in polycarbonate specimens. The found solubility is used to develop a general methodology for measurement of radioactive noble gases in air and water. The methodology is tested in pilot measurements of 133Xe in air under real conditions. The results demonstrate sufficient potential for practical applications.

n order to studying long-term climate variability and globe environment change, Solar Total Irradiance Monitor (STIM) is constructed planed to aboard on FY-3 sun-synchronous polar orbit weather satellites. STIM is made up of three same absolute radiometers, which are similar with Solar Irradiance Absolute Radiometers (SIAR). We designate one radiometer as revising radiometer. It works only one day once one or two months to demarcate the drift of the other two radiometers. Solar irradiance is measured when the sun scans over the field of view of the absolute radiometers, respectively. The irradiance measurement is carried on at the position near the North Polar after the satellite move out the shade of the earth. SIAR is electro-calibrated cavity absolute radiometer. SIAR-1 had completed The Ninth International Pyrheliometer Comparisons (IPC-IX) with World Radiometric Reference (WRR) in Physikalisch-Meteorologisches Observatorium Davos /World Radiation Center (PMOD/WRC), Switzerland from 25 September to 13 October 2000, the comparison results showed that SIAR-1 is 0.078% higher than WRR. So SIAR-1 was given a WRR calibration factor 0.99922. Where after, we compared STIM with SIAR-1, and draw a conclusion: that the absolute accuracy of STIM is better than 0.2%.

We study measures on the real line and present various versions of what it means for such a measure to take only finitely many values. We then study perturbations of the Laplacian by such measures. Using Kotani-Remling theory, we show that the resulting operators have empty absolutely continuous spectrum if the measures are not periodic. When combined with Gordon type arguments this allows us to prove purely singular continuous spectrum for some continuum models of quasicrystals.

In this monograph, we construct and study a sigma-finite measure on continuous functions from R_+ to R, strongly related to many probability measures obtained by penalisation of Brownian motion, i.e. as limits of probabilities which are absolutely continuous with respect to Wiener measure. This remarkable sigma-finite measure can be generalized in three other cases: one can start from a two-dimensional Brownian motion, from a recurrent diffusion with values in R_+, and from a discrete, recurrent Markov chain.

Aim: We assess the perspective of patients with thyroid disease towards radiation and radioactivity by means of a cultural-anthropological approach based on qualitative measures and quantitative scores. From the interviews with the patients we evaluate as to how much radioactivity is accepted as an abstract term or as a benefit within the medical context. Patients, methods: 68 patients with autonomously functioning thyroid lesions (35 women, 33 men, 32-81 years) were included in this study. All patients were interviewed in an open dialogue with the principal investigator. Patients were asked to describe their attitude towards radioactivity in general and towards radioiodine therapy in particular. Patients were asked to use a scoring system (1=positive, 5=negative) to quantify their attitudes. Results: The responses of all patients towards radioactivity in general were heterogeneous with most responses reflecting a negative perception. Many patients expressed their associated fears about atomic energy, malignant diseases and radioactive contamination. The scoring system reflected a mostly negative opinion base. However, patients became more positive once they assumed an immediate benefit of radioactivity for the treatment of their own disease (p=0.01). Conclusions: Knowing about significant differences in patient's perception about radioactivity in general or in the clinical context may help to optimise and tailor the initial, pre-therapeutical interview towards the patient. (orig.)

On April 26, 1986, explosion occurred in Chernobyl nuclear power station in USSR, and radioactivity contamination was brought about in almost all countries in the world. In European countries, crops were contaminated directly with radioactive fallout to high concentration. Also in Japan, after one week the radioactivity higher than usual was detected in environment, and also in vegetables, milk, tea leaves and others. Thereafter, in order to cope with the import of contaminated foods, inspection and watch system was strengthened by deciding the interim limit of radioactive concentration. However the cases of exceeding the interim limit were often reported. In order to remove the harmful foods due to radioactive contamination and to meet the fear of consumers, the authors measured the radioactive concentration in foods distributed in Tokyo and investigated the actual state of contamination. The samples were 920 imported foods. The experimental method, the preparation of samples, the method of analysis and the results are reported. The samples in which the radioactive concentration exceeding 50 Bq/kg was detected were 25 cases. The food having the high frequency of detection was flavors. (K.I.).

Reliable analyses of high level radioactive glass and sludge are necessary for successful operation of the Defense Waste Processing Facility (DWPF) at the Savannah River Site (SRS). This facility will convert the radioactive waste sludges at SRS into durable borosilicate glasses for final disposal in a geologic repository. Analyses that are crucial to DWPF operation and repository acceptance of the glass are measurement of the radioactive and nonradioactive composition of the waste sludges and final glasses and measurement of the Fe(II)/Fe(III) ratio in a vitrified sample of melter feed. These measurements are based on the remote dissolutions of the glass and sludge followed by appropriate chemical analyses. Glasses are dissolved by a peroxide fusion method and a method using HF, HNO{sub 3}, H{sub 3}BO{sub 3}, and HCl acids where the solutions are heated in a microwave oven. The resulting solutions are analyzed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES) and atomic absorption spectroscopy (AAS) for nonradioactive elements and appropriate counting techniques for radioactive elements. Results for two radioactive glasses containing actual radioactive waste are also presented. Sludges are dissolved by the Na{sub 2}O{sub 2} fusion method and an aqua regia method. 8 refs., 4 tabs.

This simulation is intended to help students use what they already know (elementary probability) to the concept of radioactive decay and how it can be used to determine the absolute age of an igneous rock. The students will be simulating atoms of a radioactive isotope such as radiocarbon or uranium with M & M's or some other flattish object with differently-marked sides. They simulate a half-life by shaking the M & M's and dropping them onto a sheet of paper. Roughly half of them will fall with the blank side up, just as half of the radioactive atoms decay into another element during a half-life. The students will remove the blank M & M's, graph the number of undecayed ones, and shake those, simulating another half-life. The students will pool their data, examine the effect of sample size, and assess how many half-lives it takes to run out of countable undecayed atoms. This model explains why real radiometric dating labs require minimal starting sample sizes and cannot give dates beyond a certain range (>40,000 yrs) for radiocarbon.

The startup of the LHC (Large Hadron Collider) has initialized a new era in particle physics. The standard model of particle physics has for the last 40 years with tremendous success described all measurements with phenomenal precision. The experiments at the LHC will test the standard model in a new energy regime. To normalize the measurements and understand the potential discoveries of the LHC experiments it is often crucial to know the interaction rate - the absolute luminosity. The ATLAS (A Toroidal LHC ApparatuS) detector will measure luminosity by numerous methods. But for most of the methods only the relative luminosity is measured with good precision. The absolute scale has to be provided from elsewhere. Therefore ATLAS plans to measure the flux of protons scattered under very small angles as this flux relates directly and with good precision to the absolute luminosity. This will be done by the ALFA (Absolute Luminosity For ATLAS) detector. The detectors will be positioned about 240 m from the interac...

Purpose We compared quantitative indices estimated by use of technetium-99m galactosyl human serum albumin (99mTc-GSA) single-photon emission computed tomography (SPECT)/computed tomography (CT) fused imaging and hepatic fibrosis in patients with chronic liver disease. Materials and methods On the basis of pathological findings we divided 161 patients into non-severe and severe fibrosis groups (n?=?81 and n?=?80, respectively). We measured 2 indices by 99mTc-GSA SPECT/CT fused imaging: liver uptake value (LUV)?=?[radioactivity (whole liver)/radioactivity (injected)]??100/body surface area, and functional liver index (FLI)?=?[radioactivity (hepatocytes)/radioactivity (injected)]??100/liver volume. We compared these indices with biochemical and histopathological results. Results Univariate...

In view of the persisting and understandable fear of parents with regard to radioactivity in the food of their babies as a consequence of the Chernobyl reactor accident, the Commission on Nutrition of the Deutsche Gesellschaft fuer Kinderheilkunde (German Society of Pediatrics) and the Strahlenschutzkommission have published a statement. According to this statement, the maximum permissible level of radioactivity in commercial baby food has been fixed by the EC to be 370 Bq/kg. The dietetic food industry itself has fixed a maximum for its products which is only a tenth of the radioactivity level permitted by the EC directive. The milk powders for infants tested since the reactor accident contained no measurable radioactivity or only very low amounts of Cs 134 or Cs 137, correspondung to a maximum of 25 Bq/kg in the product. Late damage to health is not to be expected. (orig./ECB).

This paper describes the natural radioactivity of groundwater occurring in sedimentary (Bauru and Guarani) and fractured rock (Serra Geral) aquifer systems in the Parana sedimentary basin, South America that is extensively used for drinking purposes, among others. The measurements of gross alpha and gross beta radioactivity as well the activity concentration of the natural dissolved radionuclides ^4^0K, ^2^3^8U, ^2^3^4U, ^2^2^6Ra, ^2^2^2Rn, ^2^1^0Po and ^2^1^0Pb were held in 80 tubular wells drilled in 21 municipalities located at Sao Paulo State and its border with Mato Grosso do Sul State in Brazil. Most of the gross alpha radioactivity data were below 1mBq/L, whereas values exceeding the gross beta radioactivity detection limit of 30mBq/L were found. The radioelement solubility in the s...

The size distributions of sup 3 sup 8 Cl, sup 3 sup 9 Cl, sup 8 sup 2 Br and sup 8 sup 4 Br aerosols generated by irradiations of argon and krypton gases containing di-octyl phthalate (DOP) aerosols with 45 MeV and 65 MeV quasi-monoenergetic neutrons were measured in order to study the formation mechanism of radioactive particles in high energy radiation fields. The effects of the size distribution of the radioactive aerosols on the size of the added DOP aerosols, the energy of the neutrons and the kinds of nuclides were studied. The observed size distributions of the radioactive particles were explained by attachment of the radioactive atoms generated by the neutron-induced reactions to the DOP aerosols. (author)

An xyz-measuring table with a modular design has been developed for the determination of the individual 3D dose rate distributions of different brachytherapy sources requiring a high spatial resolution and reproducibility. The instrumental setup consists of a plastic scintillator detector system and the xyz-measuring table for guiding the detector across the radioactive sources. For this purpose, a micro positioning system with piezo inertial drives is chosen, providing a step width of 450 nm. To ensure a high reproducibility and accuracy better than 1 ?m, an exposed linear encoder controls the positioning. The successful operation of the xyz-measuring table is exemplarily shown by measurements of dose profiles of two brachytherapy sources, an ophthalmic plaque and a radioactive seed. The setup allows a fully automated quality assurance of ophthalmic plaques and radioactive seeds under clinical conditions and can be extended to other (brachytherapy) sources of similar dimensions. PMID:23079859

The objectives of the research performed in the area of low-level radioactivity measurements are (1) to maintain and develop techniques for the measurement of low-level environmental and biological samples, (2) to measure these samples by means of low-background counters (liquid scintillators, proportional counters, ZnS counters, alpha spectrometry), (3) to support and advice the nuclear and non-nuclear industry in matters concerning radioactive contamination and/or low-level radioactivity measurements; (4) to maintain the quality assurance system according to the EN45001/ISO17025 standard; and (5) to assess the internal dose from occupational intakes of radionuclides of workers of the nuclear industry. Progress and achievements in these areas in 2000 are reported.

The in vivo interaction of methylene chloride and its metabolites with F344 rat and B6C3F1 mouse lung and liver DNA was measured after inhalation exposure to 4000 ppm (14C)methylene chloride for 3 hr. DNA was isolated from the tissues 6, 12, and 24 hr after the start of exposure and analyzed for total radioactivity and the distribution of radioactivity within enzymatically hydrolyzed DNA samples. Covalent binding to hepatic protein was also measured. A further group of rats and mice were dosed intravenously with (14C)formate after exposure to nonradiolabeled methylene chloride for 3 hr to determine the pattern of labeling resulting from incorporation of formate into DNA via the C-1 pool. Low levels of radioactivity were found in DNA from lungs and livers of both rats and mice exposed to (14C)methylene chloride. Two- to fourfold higher levels were found in mouse DNA and protein than in rat. Chromatographic analysis of the DNA nucleosides showed the radioactivity to be associated with the normal constituents of DNA. No peaks of radioactivity were found that did not coincide with peaks of radioactivity present in hydrolyzed DNA from formate-treated rats and mice. Under the conditions of this study there was no evidence for alkylation of DNA by methylene chloride in either rats or mice.

Experiments measuring rare events, such as neutrinoless double beta (0{nu}{beta}{beta}) decay, and those searching for, or measuring very weakly interacting particles, such as low energy solar neutrino experiments or direct dark matter searches, require ever lower backgrounds; particularly those from radioactive contamination of detector materials. The underground physics community strives to identify and develop materials with radioactive contamination at permissible levels, and to remove radioactive contaminants from materials, but each such material represents a separate dedicated research and development effort. This project attempted to help these research communities by expanding the capabilities in the United States, for indentifying low levels of radioactive contamination in detector materials through gamma ray spectroscopy. Additionally the project tried to make a cross comparison between well established gamma ray spectroscopy techniques for identifying radioactive contaminations and Inductively Coupled Plasma Mass Spectroscopy, which is a relatively new method for searching for uranium and thorium in materials. The project also studied the removal of radioactive radon gas for laboratory air, which showed that an inexpensive technologically simple radon scrubber can potentially be used for homes or businesses with high radon levels even after the employment of other mitigation techniques.

This chapter presents the different methods used or potentially useful to determine the age of an impact event on terrestrial planets or meteorite parent bodies. Two approaches exist: (1) geological methods such as Stratigraphy, which is the study of succeeding geological events, and (2) methods based on natural radioactivity (radiometric dating), as well as the measurement of isotopes produced by cosmic rays in space or on the Earth's surface. The nuclear methods are preferentially discussed because they yield absolute ages, whereas geological methods define relative ages only. Shock metamorphic effects on minerals and rocks are presented in the frame of an impact crater. The different phase transformations induced by shock wave passage are typical for high-pressure regimes (20-60 GPa) which cannot be produced by any classical geological process like regional metamorphism or magmatism. In consequence, impacts produce rocks called "impactites" that are very distinct from lithologies of continental or oceanic crust. Their composition varies between molten glass (tektites and spheruls), diaplectic glasses (amorphous phases), breccias with either entirely or partially glassy matrix, and rock fragments enclosed in a fine grained fragmental matrix. To determine an age, isotopic equilibrium must be achieved among the newly produced phases. Such conditions are potentially present in glasses that are produced by residual heat after decompression ( C). The best candidates on the large scale are: samples taken in melt layers of craters, in the glassy matrix of breccias in the crater area, as well as tektites and spheruls found in distant ejecta. The presence of such types of ejecta allows to date the impact event through the analyses of layers preserved in sediments. An excellent example for this scenario is the Cretaceous-Tertiary boundary where a large series of impact produced minerals have been preserved. In certain cases, it is possible to trace events even if the crater remains unknown. The majority of shock-wave produced rocks are not in isotopic equilibrium, and often the values measured represent mixed ages or disturbed systems, not giving the impact age. Only the combination of different dating methods, and very selective sample selection allows impact dating.

AGTO is a scientific project between Taiwanese and French institutes, which aim is to improve tectonic knowledge of Taiwan primarily using absolute gravity measurements and permanent GPS stations. Both tools are indeed useful to study vertical movements and mass transfers involved in mountain building, a major process in Taiwan located at the convergent margin between Philippine Sea plate and Eurasian plate. This convergence results in two subductions north and south of Taiwan (Ryukyu and Manilla trenches, respectively), while the center is experiencing collision. These processes make Taiwan very active tectonically, as illustrated by numerous large earthquakes and rapid uplift of the Central Range. High slopes of Taiwan mountains and heavy rains brought by typhoons together lead to high landslides and mudflows risks. Practically, absolute gravity measurements have been yearly repeated since 2006 along a transect across south Taiwan, from Penghu to Lutao islands, using FG5 absolute gravimeters. This transect contains ten sites for absolute measurements and has been densified in 2008 by incorporating 45 sites for relative gravity measurements with CG5 gravimeters. The last relative and absolute measurements have been performed in November 2009. Most of the absolute sites have been measured with a good accuracy, about 1 or 2 ?Gal. Only the site located in Tainan University has higher standard deviation, due to the city noise. We note that absolute gravity changes seem to follow a trend in every site. However, straightforward tectonic interpretation of these trends is not valuable as many non-tectonic effects are supposed to change g with time, like groundwater or erosion. Estimating and removing these effects leads to a tectonic gravity signal, which has theoretically two origins : deep mass transfers around the site and vertical movements of the station. The latter can be well constrained by permanent GPS stations located close to the measurement pillar. Deep mass transfers, on the contrary, must be evaluated by modelling. Relative gravity, despite lower accuracy, enable us to cover wider area (about 10 000 km2). Our interest is thus to merge both types of measurements to have a large overview of temporal g changes in the south of Taiwan.