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Sample records for artificial radioactive isotopes

  1. Natural decrease of the intensity level of artificial radioactive isotopes in the Barents Sea

    NASA Astrophysics Data System (ADS)

    Matishov, G. G.; Matishov, D. G.; Solatie, D.; Kasatkina, N. E.; Leppanen, A.

    2009-08-01

    The results of radioecological investigations carried out within the framework of the Russian-Finnish high-latitude expedition in 2007 are presented. The characteristics of the present-day accumulation level of the significant radioecological isotopes 137Cs, 90Sr and 239,240Pu in the Barents Sea are described. The comparative analysis is performed for the radiation pollution of the environment in the 1980s and 1990s and in the first decade of the 21st century. Natural purification processes in the marine environment are the main factors of the decrease in the intensity level of artificial radioactive isotopes. These processes include repeated dilution, nuclear decay, occlusion by sediments and suspended solid material, and accumulation by aquatic inhabitants. A stable decreasing trend is observed for the intensity level of artificial radioactive isotopes in the Barents Sea.

  2. Investigations of natural and artificial radioactive isotopes in seawater and sediments in the Yellow Sea and adjacent southeast area

    NASA Astrophysics Data System (ADS)

    Li, Peiquan; Yu, Yinting

    1992-12-01

    Investigations of natural and artificial radioisotopes including90Sr,137Cs, gross β and U carried out in the Yellow Sea and adjacent southeast area in 1963, 1964, 1975 and 1978 showed that radioactive pollution by90Sr and137Cs from atmospheric fallout had gradually decreased with time due to the cessation of atmospheric nuclear weapons tests in the 70s. The distributions of natural and artificial radioactive isotopes (U, Ra, Th,40K and137Cs) in sediments southwest of Jizhou Island were uniform. The more uniform may be related to the soluble species of U[Uo2(Co3)4] in the seawater. The high value of Th at stations 3 and 6 was related to the sandy clay sediment; the low value at station 8 was related to sandy sediment. The content of137Cs in the eddy area being less than about half of that in the China inshore area showed that the source of137Cs may be insufficient orthat the conditions for enriching137Cs in the circulation eddy area were not favorable.

  3. The Discovery of Artificial Radioactivity

    NASA Astrophysics Data System (ADS)

    Guerra, Francesco; Leone, Matteo; Robotti, Nadia

    2012-03-01

    We reconstruct Frédéric Joliot and Irène Curie's discovery of artificial radioactivity in January 1934 based in part on documents preserved in the Joliot-Curie Archives in Paris, France. We argue that their discovery followed from the convergence of two parallel lines of research, on the neutron and on the positron, that were focused on a well-defined experimental problem, the nuclear transmutation of aluminum and other light elements. We suggest that a key role was played by a suggestion that Francis Perrin made at the seventh Solvay Conference at the end of October 1933, that the alpha-particle bombardment of aluminum produces an intermediate unstable isotope of phosphorus, which then decays by positron emission. We also suggest that a further idea that Perrin published in December 1933, and the pioneering theory of beta decay that Enrico Fermi also first published in December 1933, established a new theoretical framework that stimulated Joliot to resume the researches that he and Curie had interrupted after the Solvay Conference, now for the first time using a Geiger-Müller counter to detect the positrons emitted when he bombarded aluminum with polonium alpha particles.

  4. Atmospheric radioactive isotopes at orbital altitudes.

    PubMed

    Gregory, J C

    1996-11-01

    The radioactive isotope 7Be was discovered on the forward-facing side of the LDEF satellite in amounts far exceeding that expected from direct cosmic ray activation of the spacecraft material. This prompted an examination of the production of cosmogenic isotopes in the atmosphere and of the processes by which they may be transported to orbital altitudes and adsorbed by a spacecraft. 7Be is only one of several atmospheric cosmogenic isotopes that might be detectable at orbital altitudes and that might prove to be as useful as tracers of atmospheric circulation processes in the mesosphere and thermosphere as they have been in the lower layers of the atmosphere.

  5. Radioactivity of natural and artificial building materials - a comparative study.

    PubMed

    Szabó, Zs; Völgyesi, P; Nagy, H É; Szabó, Cs; Kis, Z; Csorba, O

    2013-04-01

    Building materials and their additives contain radioactive isotopes, which can increase both external and internal radioactive exposures of humans. In this study Hungarian natural (adobe) and artificial (brick, concrete, coal slag, coal slag concrete and gas silicate) building materials were examined. We qualified 40 samples based on their radium equivalent, activity concentration, external hazard and internal hazard indices and the determined threshold values of these parameters. Absorbed dose rate and annual effective dose for inhabitants living in buildings made of these building materials were also evaluated. The calculations are based on (226)Ra, (232)Th and (40)K activity concentrations determined by gamma-ray spectrometry. Measured radionuclide concentrations and hence, calculated indices and doses of artificial building materials show a rather disparate distribution compared to adobes. The studied coal slag samples among the artificial building materials have elevated (226)Ra content. Natural, i.e. adobe and also brick samples contain higher amount of (40)K compared to other artificial building materials. Correlation coefficients among radionuclide concentrations are consistent with the values in the literature and connected to the natural geochemical behavior of U, Th and K elements. Seven samples (coal slag and coal slag concrete) exceed any of the threshold values of the calculated hazard indices, however only three of them are considered to be risky to use according to the fact that the building material was used in bulk amount or in restricted usage. It is shown, that using different indices can lead to different conclusions; hence we recommend considering more of the indices at the same time when building materials are studied. Additionally, adding two times their statistical uncertainties to their values before comparing to thresholds should be considered for providing a more conservative qualification. We have defined radon hazard portion to point

  6. Review of physics, instrumentation and dosimetry of radioactive isotopes

    NASA Technical Reports Server (NTRS)

    Sinclair, W. K.

    1967-01-01

    General radioactive isotope information, stressing radioactivity, methods of measurement, and dosimetry of radioactive nuclides have been reviewed to serve as a reference for the medical profession. Instability of radionuclides, principal types of emission, and measurement of ionizing radiation are among the topics discussed.

  7. Influence of natural radioactive aerosols on artificial radioactivity detection in the Spanish surveillance networks.

    PubMed

    Vargas, A; Arnold, D; Ortega, X; Parages, C

    2008-11-01

    The device used for continuous measurements of artificial alpha and beta activity in Spanish radiological surveillance networks is the LB BAI 9850 monitor from the Berthold Company. The temporal variation of radon decay product equilibrium introduces a varying background signal in the artificial radioactivity in these monitors. This unwanted background signal can be significantly reduced by analyzing natural radioactive aerosols and their influence on the monitor.

  8. Ion source for radioactive isotopes - IRIS ECR

    SciTech Connect

    Burke, J.T.; Freedman, S.J.; Lyneis, C.M.; Wutte, D.

    2001-01-01

    A compact electron cyclotron resonance ion source for radioactive isotopes (IRIS ECR) has been developed for the {sup 14}O experiment at the 88-Inch Cyclotron. The {sup 14}O experiment is a joint effort between the Nuclear Science Division's Weak Interaction Group and the 88-Inch Cyclotron ECR ion source group. The initial goal of the experimentalists is to measure {sup 14}O half-life and the shape of the beta decay spectrum. The 70 second half-life of {sup 14}O requires producing the isotope on-line at the 88-Inch Cyclotron. The {sup 14}O is generated in the form of {sup 12}C{sup 14}O in a high temperature carbon aerogel target using a 20 MeV {sup 3}He{sup +} beam from the LBNL 88-Inch Cyclotron via the reaction {sup 12}C({sup 3}He,n){sup 14}O. The {sup 14}O atoms are then separated from the other radioactive isotopes produced in the target and then implanted into a thin foil. The implanted target serves to minimize the radiation background and maximize the signal in the beta spectrometer by concentrating the{sup 14}O into a 5mm diameter spot. An 8 meter long stainless steel transfer line connects the target chamber to the IRIS ECR through a turbo molecular pump. The gas coming from the turbo pump is fed into the ion source and ionized, extracted at energies of 20 to 30 keV and mass separated by an analyzing magnet. The ion source started operation in spring 1999 and achieved a beam intensity of 3 x 10{sup 5} {sup 14}O{sup +} ions/second. Extensive developments on the production target were made to increase extraction efficiency of the {sup 14}O. A liquid nitrogen trap was installed between the ECR and the turbo pump to minimize the gas load to the ion source. An improved support gas injection system was installed so that multiple support gases can be introduced. A bias disk is used to stabilize the plasma. A quartz liner in the plasma chamber is used to reduce the hold-up time for oxygen and increase the overall ionization efficiency. The extraction system was

  9. Laser spectroscopy of radioactive barium and strontium isotopes

    SciTech Connect

    Martin, A.G.

    1986-01-01

    An atomic beam system and a high resolution computer controlled dye laser system were developed to perform isotope shift measurements on accelerator-produced radioactive isotopes. Two different techniques were used to transport the radioactive isotopes to the laser interaction region. The first technique was based on the thermalization and deionization of the nuclear reaction products in a helium buffer gas. The reaction products were subsequently transported in the gas to the laser beam along a capillary tube. This technique suffered from problems with chemical reactions between impurities in the buffer gas and the reaction products and proved to be unsuccessful. The second technique was based on the implantation of the reaction products into a metal lattice. Subsequent heating of the metal lattice released the implanted ions from which an atomic beam was formed. The photon burst technique was used to enable detection of the extremely weak atomic beams formed in this manner. Measurements were performed of the known isotope shifts of radioactive /sup 128/Ba and /sup 126/Ba to test the sensitivity of the system. The previously unmeasured isotope shift of radioactive /sup 82/Sr also was determined, and the result obtained was compared to predictions using the droplet model.

  10. Journal of Environmental Radioactivity special issue: international topical conference on Po and radioactive Pb isotopes.

    PubMed

    Holm, Elis; Garcia-Tenorio, Rafael

    2011-05-01

    An international conference on polonium (Po) and radioactive isotopes was held in Seville Spain, 26-28 October 2009 at the Centro Nacional de Aceleradores. It was attended by 138 participants from 38 different countries. The sessions covered all aspects on Po and lead (Pb) such as radiochemistry, terrestrial and marine radioecology, kinetics, sedimentation rates, atmospheric tracers, NORM industries and dose assessment.

  11. Natural and artificial radioactivity levels in Livingston Island (Antarctic regions)

    SciTech Connect

    Baeza, A.; Miro, C.; Paniagua, J.M.; Navarro, E.; Rodriguez, M.J.; Sanchez, F.

    1994-01-01

    Radioactive contamination of the sea and land is due, on the one hand, to fallout from atmospheric atomic explosions since 1945, and, on the other, to emissions produced by nuclear and radioactive facilities. Given its geographic position far distant from the aforementioned main sources of radioactive contamination, Antarctica should have the lowest levels that can be measured on the Earth of artificial radionuclides in the various receptor media which are characteristic of the trophic chain. In the case of Antarctica, these are melt-water, sea-water, mosses, algae, and lichens. With the aim of contributing basic information on the radiation levels present in the Antarctic ecosystem, we have identified and measured for the first time the radioactive levels of natural emitters (of cosmic and terrestrial origin) and man-made emitters in the aforementioned receptor media, in the vicinity of the Spanish Antarctic Base, Juan Carlos I, situated on Livingston Island in the South Shetland archipelago, Antarctic region. 22 refs., 1 fig., 3 tabs.

  12. Decoding Environmental Processes Using Radioactive Isotopes for the Post-Radioactive Contamination Recovery Assessment

    NASA Astrophysics Data System (ADS)

    Yasumiishi, Misa; Nishimura, Taku; Osawa, Kazutoshi; Renschler, Chris

    2017-04-01

    The continual monitoring of environmental radioactive levels in Fukushima, Japan following the nuclear plant accident in March 2011 provides our society with valuable information in two ways. First, the collected data can be used as an indicator to assess the progress of decontamination efforts. Secondly, the collected data also can be used to understand the behavior of radioactive isotopes in the environment which leads to further understanding of the landform processes. These two aspects are inseparable for us to understand the effects of radioactive contamination in a dynamic environmental system. During the summer of 2016, 27 soil core samples were collected on a farmer's land (rice paddies and forest) in Fukushima, about 20 km northwest of the nuclear plant. Each core was divided into 2.0 - 3.0 cm slices for the Cs-134, Cs-137, and I-131 level measurement. The collected data is being analyzed from multiple perspectives: temporal, spatial, and geophysical. In the forest area, even on the same hillslope, multiple soil types and horizon depths were observed which indicates the challenges in assessing the subsurface radioactive isotope movements. It appears that although highly humic soils show higher or about the same level of radioactivity in the surface layers, as the depth increased, the radioactivity decreased more in those samples compared with more sandy soils. With regard to the direction a slope faces and the sampling altitudes, the correlation between those attributes and radioactivity levels is inconclusive at this moment. The altitude might have affected the fallout level on a single hillslope-basis. However, to determine the correlation, further sampling and the detailed analysis of vegetation and topography might be necessary. Where the surface soil was scraped and new soil was brought in, former rice paddy surface layers did show three-magnitude levels lower of radioactivity in the top layer when compared with forest soils. At the foot of forest

  13. Cross-Section Measurements with the Radioactive Isotope Accelerator (RIA)

    SciTech Connect

    Stoyer, M A; Moody, K J; Wild, J F; Patin, J B; Shaughnessy, D A; Stoyer, N J; Harris, L J

    2002-11-19

    RIA will produce beams of exotic nuclei of unprecedented luminosity. Preliminary studies of the feasibility of measuring cross-sections of interest to the science based stockpile stewardship (SBSS) program will be presented, and several experimental techniques will be discussed. Cross-section modeling attempts for the A = 95 mass region will be shown. In addition, several radioactive isotopes could be collected for target production or medical isotope purposes while the main in-beam experiments are running. The inclusion of a broad range mass analyzer (BRAMA) capability at RIA will enable more effective utilization of the facility, enabling the performance of multiple experiments at the same time. This option will be briefly discussed.

  14. Metal complexes containing natural and and artificial radioactive elements and their applications.

    PubMed

    Kharissova, Oxana V; Méndez-Rojas, Miguel A; Kharisov, Boris I; Méndez, Ubaldo Ortiz; Martínez, Perla Elizondo

    2014-07-24

    Recent advances (during the 2007-2014 period) in the coordination and organometallic chemistry of compounds containing natural and artificially prepared radionuclides (actinides and technetium), are reviewed. Radioactive isotopes of naturally stable elements are not included for discussion in this work. Actinide and technetium complexes with O-, N-, N,O, N,S-, P-containing ligands, as well π-organometallics are discussed from the view point of their synthesis, properties, and main applications. On the basis of their properties, several mono-, bi-, tri-, tetra- or polydentate ligands have been designed for specific recognition of some particular radionuclides, and can be used in the processes of nuclear waste remediation, i.e., recycling of nuclear fuel and the separation of actinides and fission products from waste solutions or for analytical determination of actinides in solutions; actinide metal complexes are also usefulas catalysts forcoupling gaseous carbon monoxide,as well as antimicrobial and anti-fungi agents due to their biological activity. Radioactive labeling based on the short-lived metastable nuclide technetium-99m ((99m)Tc) for biomedical use as heart, lung, kidney, bone, brain, liver or cancer imaging agents is also discussed. Finally, the promising applications of technetium labeling of nanomaterials, with potential applications as drug transport and delivery vehicles, radiotherapeutic agents or radiotracers for monitoring metabolic pathways, are also described.

  15. Enrico Fermi's Discovery of Neutron-Induced Artificial Radioactivity: Neutrons and Neutron Sources

    NASA Astrophysics Data System (ADS)

    Guerra, Francesco; Leone, Matteo; Robotti, Nadia

    2006-09-01

    We reconstruct and analyze the path leading from James Chadwick’s discovery of the neutron in February 1932 through Frédéric Joliot and Irène Curie’s discovery of artificial radioactivity in January 1934 to Enrico Fermi’s discovery of neutron-induced artificial radioactivity in March 1934. We show, in particular, that Fermi’s innovative construction and use of radon-beryllium neutron sources permitted him to make his discovery.

  16. Automated isotope identification algorithm using artificial neural networks

    DOE PAGES

    Kamuda, Mark; Stinnett, Jacob; Sullivan, Clair

    2017-04-12

    There is a need to develop an algorithm that can determine the relative activities of radio-isotopes in a large dataset of low-resolution gamma-ray spectra that contains a mixture of many radio-isotopes. Low-resolution gamma-ray spectra that contain mixtures of radio-isotopes often exhibit feature over-lap, requiring algorithms that can analyze these features when overlap occurs. While machine learning and pattern recognition algorithms have shown promise for the problem of radio-isotope identification, their ability to identify and quantify mixtures of radio-isotopes has not been studied. Because machine learning algorithms use abstract features of the spectrum, such as the shape of overlapping peaks andmore » Compton continuum, they are a natural choice for analyzing radio-isotope mixtures. An artificial neural network (ANN) has be trained to calculate the relative activities of 32 radio-isotopes in a spectrum. Furthermore, the ANN is trained with simulated gamma-ray spectra, allowing easy expansion of the library of target radio-isotopes. In this paper we present our initial algorithms based on an ANN and evaluate them against a series measured and simulated spectra.« less

  17. Cooling of radioactive isotopes for Schottky mass spectrometry

    SciTech Connect

    Steck, M.; Beckert, K.; Eickhoff, H.; Franzke, B.; Nolden, F.; Reich, H.; Schlitt, B.; Winkler, T.

    1999-01-15

    Nuclear masses of radioactive isotopes can be determined by measurement of their revolution frequency relative to the revolution frequency of reference ions with well-known masses. The resolution of neighboring frequency lines and the accuracy of the mass measurement is dependent on the achievable minimum longitudinal momentum spread of the ion beam. Electron cooling allows an increase of the phase space density by several orders of magnitude. For high intensity beams Coulomb scattering in the dense ion beam limits the beam quality. For low intensity beams a regime exists in which the diffusion due to intrabeam scattering is not dominating any more. The minimum momentum spread {delta}p/p=5x10{sup -7} which is observed by Schottky noise analysis is considerably higher than the value expected from the longitudinal electron temperature. The measured frequency spread results from fluctuations of the magnetic field in the storage ring magnets. Systematic mass measurements have started and can be presently used for ions with half-lives of some ten seconds. For shorter-lived nuclei a stochastic precooling system is in preparation.

  18. Using isotopic ratios for discrimination of environmental anthropogenic radioactivity.

    PubMed

    Hayes, Robert B; Akbarzadeh, Mansour

    2014-10-01

    When air is pulled into the WIPP repository for ventilation purposes, this air is unfiltered and contains all the components of ubiquitous anthropogenic radionuclides from global nuclear fallout (including Cs and Pu isotopes). Although the NORM in aeolian sand and dust contribute to the gross alpha beta activity on effluent air filters, there remains a need to discriminate effluent TRU generated in the disposal process at WIPP from TRU being pulled into the repository with the unfiltered surface air. This is only evaluated using ratios of Cs and Pu activity found through radioassay of air filters taken from the mine effluent. By characterizing both the credible range of Cs/Pu ratios from the environment and those known to exist in the waste, a rigorous test criteria is attained. The use of HPGE to assay Cs in the intake dust plated out in the mine allowed a gross assay of total TRU radioactivity pulled into the mine over time from global fallout. Radiochemistry of samples from deposition in the mine's air intake shaft was also carried out. The use of net activity ratios at background levels is also shown to follow a Cauchy distribution in terms of their expected statistical distributions.

  19. Methods and devices for the separation of radioactive rare earth metal isotopes from their alkaline earth metal precursors

    SciTech Connect

    Wai, Chein M.

    1993-07-06

    A method is described for the separation of a radioactive rare earth metal isotope or a radioactive isotope of yttrium or scandium from its alkaline earth metal precursor comprising contacting a sample containing at least one of said isotopes and said precursor with an ionizable dibenzo ether derivative.

  20. Methane and radioactive isotopes in submarine hydrothermal systems

    SciTech Connect

    Kim, K.R.

    1983-01-01

    This thesis consists of two parts: 1) methane and 2) radioactive isotopes, especially radon, in submarine hydrothermal systems. Both parts deal with the use of these gases as tracers for mapping hydrothermal vents at sea, and with their relationships to other sensitive tracers such as helium, manganese, and temperature. Hydrothermal methane was used as a real-time tracer for locating new submarine hydrothermal systems along spreading axes, discovering new hydrothermal systems at two locations in Pacific Ocean: 1) 20/sup 0/S on East Pacific Rise, and 2) Mariana Trough Back-arc Basin. Methane shows good correlations with helium-3 and temperature with similar ratios in various hydrothermal systems, 3 to 42 x 10/sup 6/ for the methane to helium-3 ratio, and 3 to 19 ..mu.. cc/kg/sup 0/C for the methane to temperature anomaly. These similar ratios from different areas provide evidence for chemical homogeneity of submarine hydrothermal waters. A good correlation between methane and manganese appears to be associated only with high-temperature hydrothermal systems. Radioisotopes in the vent waters of 21/sup 0/N high-temperature hydrothermal system have end-member concentrations of 7.5 to 40 dpm/kg for Ra-226, 360 dpm/kg for Rn 222, 62 dpm/kg for Pb-210, and 19 dpm/kg for Po-210. The radon activity for this system is one order of magnitude lower, and the Pb-210 activity is one order or magnitude higher, than those a the low temperature Galapagos system. All these observations suggest that the high radon, and low Pb-210 activity observed in Galapagos system may originate from the extensive subsurface mixing and water-rock interaction in this system (direct injection of radon and scavenging of Pb-210).

  1. Simple isotopic method using oral stable or radioactive tracers for estimating fractional calcium absorption in adult women.

    PubMed

    Lee, W H; McCabe, G P; Martin, B R; Weaver, C M

    2011-06-01

    We extended a simple oral method for estimating fractional calcium absorption determined by double isotopic methods using radioactive or stable isotope across wide age of adult women. Fractional calcium absorption can be estimated by using either a radioactive or stable oral isotope across the entire age spectrum of adult women. A method for estimating fractional calcium absorption using a single serum collection following a single oral radioactive isotopic tracer has been validated against a classical double isotopic tracer ratio method in adults. Our goal was to extend this simplified method to include use of stable isotopes and a broad age range. We used our database of 56 observations from 26 white adult women aged 19-67 years receiving either radioactive or stable isotopes. Reference values for fractional calcium absorption were determined from 24-h double isotopic ratios in serum and urine and from full kinetic modeling. Equations for estimating fractional calcium absorption were developed from isotopic enrichment in serum and urine from an oral tracer and measures of body size using the multiple linear regression analysis. Equations using a 4- to 6-h sample following an oral dose of either a stable or radioactive isotope corrected for body size were highly correlated with the reference values for fractional calcium absorption across different aged populations (r > 0.8, p < 0.001). Fractional calcium absorption can be estimated by a single oral tracer method using either radioactive or stable calcium isotopes across the entire age spectrum in healthy white adult women.

  2. Treatment of arthritis, including rheumatoid arthritis, with radioactive isotopes

    SciTech Connect

    Lieberman, E.; Bordoni, M.E.; Thornton, A.K.

    1988-06-21

    A radioactive composition is described for the treatment of arthritis comprising, in combination, a ferric hydroxide or aluminum hydroxide aggregate suspension having a particle size of 3 to 20 microns, wherein a radionuclide is entrapped, the radionuclide being /sup 166/Holmium.

  3. Novel methods for estimating 3D distributions of radioactive isotopes in materials

    NASA Astrophysics Data System (ADS)

    Iwamoto, Y.; Kataoka, J.; Kishimoto, A.; Nishiyama, T.; Taya, T.; Okochi, H.; Ogata, H.; Yamamoto, S.

    2016-09-01

    In recent years, various gamma-ray visualization techniques, or gamma cameras, have been proposed. These techniques are extremely effective for identifying "hot spots" or regions where radioactive isotopes are accumulated. Examples of such would be nuclear-disaster-affected areas such as Fukushima or the vicinity of nuclear reactors. However, the images acquired with a gamma camera do not include distance information between radioactive isotopes and the camera, and hence are "degenerated" in the direction of the isotopes. Moreover, depth information in the images is lost when the isotopes are embedded in materials, such as water, sand, and concrete. Here, we propose two methods of obtaining depth information of radioactive isotopes embedded in materials by comparing (1) their spectra and (2) images of incident gamma rays scattered by the materials and direct gamma rays. In the first method, the spectra of radioactive isotopes and the ratios of scattered to direct gamma rays are obtained. We verify experimentally that the ratio increases with increasing depth, as predicted by simulations. Although the method using energy spectra has been studied for a long time, an advantage of our method is the use of low-energy (50-150 keV) photons as scattered gamma rays. In the second method, the spatial extent of images obtained for direct and scattered gamma rays is compared. By performing detailed Monte Carlo simulations using Geant4, we verify that the spatial extent of the position where gamma rays are scattered increases with increasing depth. To demonstrate this, we are developing various gamma cameras to compare low-energy (scattered) gamma-ray images with fully photo-absorbed gamma-ray images. We also demonstrate that the 3D reconstruction of isotopes/hotspots is possible with our proposed methods. These methods have potential applications in the medical fields, and in severe environments such as the nuclear-disaster-affected areas in Fukushima.

  4. Mass measurements on radioactive isotopes with a Penning trap mass spectrometer

    SciTech Connect

    Bollen, G.; Ames, F.; Schark, E.; Audi, G.; Lunney, D.; Saint Simon, M. de; Beck, D.; Herfurth, F.; Kluge, H.-J.; Kohl, A.; Schwarz, S.; Moore, R. B.; Szerypo, J.

    1999-01-15

    Penning trap mass measurements on short-lived isotopes are performed with the ISOLTRAP mass spectrometer at the radioactive beam facility ISOLDE/CERN. In the last years the applicability of the spectrometer has been considerably extended by the installation of an RFQ trap ion beam buncher and a new cooler Penning trap, which is operated as an isobar separator. These improvements allowed for the first time measurements on isotopes of rare earth elements and on isotopes with Z=80-85. In all cases an accuracy of {delta}m/m{approx_equal}1{center_dot}10{sup -7} was achieved.

  5. Radioactive halos and ion microprobe measurement of Pb isotope ratios

    NASA Technical Reports Server (NTRS)

    Gentry, R. V.

    1974-01-01

    This investigation was to obtain, if possible, the Pb isotope ratios of both lunar and meteoritic troilite grains by utilizing ion microprobe techniques. Such direct in situ measurement of Pb isotope ratios would eliminate contamination problems inherent in wet chemistry separation procedures, and conceivably determine whether lunar troilite grains were of meteoritic origin. For comparison purposes two samples of meteoritic troilite were selected (one from Canyon Diablo) for analysis along with two very small lunar troilite grains (approximately 50-100 microns). It was concluded that the ion microprobe as presently operating, does not permit the in situ measurement of Pb isotope ratios in lunar or meteoritic troilite. On the basis of these experiments no conclusions could be drawn as to the origin of the lunar troilite grains.

  6. Process for disposal of aqueous solutions containing radioactive isotopes

    DOEpatents

    Colombo, Peter; Neilson, Jr., Robert M.; Becker, Walter W.

    1979-01-01

    A process for disposing of radioactive aqueous waste solutions whereby the waste solution is utilized as the water of hydration to hydrate densified powdered portland cement in a leakproof container; said waste solution being dispersed without mechanical inter-mixing in situ in said bulk cement, thereafter the hydrated cement body is impregnated with a mixture of a monomer and polymerization catalyst to form polymer throughout the cement body. The entire process being carried out while maintaining the temperature of the components during the process at a temperature below 99.degree. C. The container containing the solid polymer-impregnated body is thereafter stored at a radioactive waste storage dump such as an underground storage dump.

  7. Calculation of in-target production rates for radioactive isotope beam production at TRIUMF

    NASA Astrophysics Data System (ADS)

    Garcia, Fatima; Andreoiu, Corina; Kunz, Peter; Laxdal, Aurelia

    2016-09-01

    Rare Isotope Beam (RIB) facilities around the world, such as TRIUMF, work towards development of new target materials to generate exotic species. Access to these rare radioactive isotopes is key for applications in nuclear medicine, astrophysics and fundamental nuclear science. To better understand production from these and other materials, we have built a computer simulation of the RIB targets used at the TRIUMF Isotope Separation and ACceleration (ISAC) facility, to support new target material development. Built at Simon Fraser University, the simulation runs in the GEANT4 nuclear transport toolkit, and can simulate the production rate of isotopes from a given set of beam and target characteristics. The simulation models the bombardment of a production target by an incident high-energy proton beam and calculates isotope in-target production rates different nuclear reactions. Results from the simulation will be presented, along with an evaluation of various nuclear reaction models and a experimentally determined RIB yields at the ISAC Yield Station.

  8. Synthesis of nucleoside 5'-triphosphates labelled with radioactive phosphorus isotopes

    NASA Astrophysics Data System (ADS)

    Skoblov, Yurii S.; Korolev, A. E.; Maslova, R. N.

    1995-08-01

    The review presents an analysis of the chemical chemicoenzymic, and enzymic methods of synthesis of nucleoside 5'-triphosphates labelled with phosphorus isotopes ( 32P and 33P) in the α- and γ-positions. The major part of the review is devoted to enzymic methods of synthesis, because they have undoubted advantages. The enzymatic reactions are described in detail, the specificity and availability of the enzymes are considered, and data on the radiation stability of certain enzymes are presented. The bibliography includes 29 references.

  9. Laser fluorescence on radio-active isotopes produced in very low yield

    NASA Astrophysics Data System (ADS)

    Dancy, M. P.; Billowes, J.; Grant, I. S.; Evans, D. E.; Griffith, J. A. R.; Wells, S. A.; Eastham, D. A.; Groves, J.; Smith, J. R. H.; Tolfree, D. W. L.; Walker, P. M.

    1990-08-01

    East particle-photon coincidence techniques, developed at Daresbury with strontium isotopes, allow ultrasensitive laser fluorescence spectroscopy of beams of radio-active isotopes which can only be produced in very low yields. The technique has now been applied to neutron-deficient barium isotopes down to120Ba. From measured hyperfine splittings and isotope shifts, nuclear moments and changes in mean square radii have been determined. The work has revealed an abrupt increase in the mean square radius for121Ba large enough to disrupt the systematic staggering of nuclear size seen for the series. In a recent experiment an isomeric state of127Ba with a half-life of about 2 seconds has been produced in a very low yield; nevertheless we have succeeded in obtaining a fluorescence spectrum.

  10. Incorporation of stable and radioactive isotopes via organoborane chemistry

    SciTech Connect

    Kabalka, G.W.

    1984-06-01

    An organic synthesis involving the use of organoboranes rather than the traditional substitution reactions and Grignard reagents for the rapid preparation of physiologically active materials labelled with short-lived isotopes is discussed in detail. The iodination reaction for incorporating I-123 or I-125 into compounds was found to proceed via an electrophilic attack by the iodine molecule on the electron-rich borax complex, did not require the presence of strong base, and was complete in 60 sec. The procedure also uses radiolabeled NaI rather than the more unstable iodine monochloride usually used. A similar procedure was developed for labelling compounds with Br-77. Other direct one-pot syntheses are described for incorporation of O-17, N-13, N-15, C-11, and C-13 into compounds very rapidly.

  11. Monitoring natural and artificial radioactivity enhancement in the Aegean Sea using floating measuring systems.

    PubMed

    Tsabaris, C

    2008-11-01

    In the present work, the enhancement of radioactivity due to rainfall in the Aegean Sea using floating measuring systems was observed and quantified. The data were acquired with a NaI underwater detection system, which was installed on a floating measuring system at a depth of 3m. The results of natural and artificial radioactivity are discussed taking into account the rainfall intensity and wind direction. The activity concentration of (214)Bi increased up to (991+/-102)Bq/m(3) after strong rainfall in the North Aegean Sea in winter (humid period) with east wind direction. On other hand, the maximum activity concentration reached the level of (110+/-10)Bq/m(3) in summer (dry period) during south winds.

  12. TRIμP - a radioactive isotope trapping facility under construction at KVI

    NASA Astrophysics Data System (ADS)

    Berg, G. P.; Dendooven, P.; Dermois, O.; Harakeh, M. N.; Hoekstra, R.; Jungmann, K.; Kopecky, S.; Morgenstern, R.; Rogachevskiy, A.; Timmermans, R.; Willmann, L.; Wilschut, H. W.

    2003-05-01

    At the Kernfysisch Versneller Instituut a new facility (TRIμP) is under development which aims to investigate fundamental interactions using radioactive ions. A spectrum of radioactive isotopes will be produced in inverse-kinematics and fragmentation reactions using heavy-ion beams from the superconducting cyclotron AGOR. The reaction products will be separated from the primary beam in a dual-mode recoil and fragment separator. The beam of isotopes of interest will be transformed into a low-energy, high-quality, bunched beam and, after neutralization, stored in an atom trap. The emphasis will be put on studying the origin of parity violation via β-ν angular correlations and the search for permanent electric dipole moments of atoms and nuclei. The facility will be open to outside users; suggestions for collaborations to extend the scientific program are encouraged.

  13. The MOON-1 detector construction and the study of backgrounds from radioactive isotopes

    NASA Astrophysics Data System (ADS)

    Ogama, T.; Nakamura, H.; Ejiri, H.; Fushimi, K.; Ichihara, K.; Matsuoka, K.; Nomachi, M.; Hazama, R.; Umehara, S.; Yoshida, S.; Sakiuchi, T.; Hai, V. H.; Sugaya, Y.; Moon Collaboration

    2006-05-01

    MOON is a multilayer system of plastic scintillators and 100Mo films for 100Mo 0νββ decays. A prototype detector MOON-1 was built with 6 layers of plastic scintillators and 142g of 100Mo films for background (BG), energy and position resolution studies of the MOON detector. No serious BG from natural radioactive isotopes (RI) for 0νββ detection was found.

  14. Measuring oxygen isotopes beyond the neutron dripline: Two-neutron emission and radioactivity

    NASA Astrophysics Data System (ADS)

    Kohley, Zach

    2013-10-01

    The availability of rare isotope beams has made it possible to extend nuclear structure measurements to nuclei far away from stability. Drastic changes in the structure, properties, and available decay-modes of these exotic isotopes have been observed in comparison to their stable counterparts. The oxygen isotopic chain has been particularly interesting with observations of new shell closures at N = 14 and N = 16. The MoNA-LISA/Sweeper setup at the National Superconducting Cyclotron Laboratory at Michigan State University has allowed for studies of the oxygen isotopes to be extended beyond the neutron dripline. Recently, the 26O ground state was observed for the first time and shown to be unbound by less than 200 keV. The low energy ground state of the two-neutron unbound 26O opened the possibility for the discovery of two-neutron radioactivity. A new technique was developed to measure the lifetimes of neutron unbound nuclei in the picosecond range. This technique was applied to the 26O decay and a half-life of 4.5-1. 5 + 1 . 1 (stat.) +/-3 (sys.) ps was extracted. This corresponds to 26O having a finite lifetime at an 82% confidence level and, thus, suggests the possibility of two-neutron radioactivity. Supported by the National Science Foundation, under Grant No. PHY-1102511.

  15. Artificial and natural radioactivity in edible mushrooms from Sao Paulo, Brazil.

    PubMed

    de Castro, L P; Maihara, V A; Silva, P S C; Figueira, R C L

    2012-11-01

    Environmental biomonitoring has demonstrated that organisms such as crustaceans, fish and mushrooms are useful to evaluate and monitor both ecosystem contamination and quality. Particularly, some mushroom species have a high capacity to retain radionuclides and some toxic elements from the soil and the air. The potential of mushrooms to accumulate radionuclides in their fruit-bodies has been well documented. However, there are no studies that determine natural and artificial radionuclide composition in edible mushrooms, in Brazil. Artificial ((137)Cs) and natural radioactivity ((40)K, (22)(6)Ra, (2)(28)Ra) were determined in 17 mushroom samples from 3 commercialized edible mushroom species. The edible mushrooms collected were Agaricus sp., Pleurotus sp. and Lentinula sp. species. The activity measurements were carried out by gamma spectrometry. The levels of (137)Cs varied from 1.45 ± 0.04 to 10.6 ± 0.3 Bq kg(-1), (40)K levels varied from 461 ± 2 to 1535 ± 10 Bq kg(-1), (2)(26)Ra levels varied from 14 ± 3 to 66 ± 12 Bq kg(-1) and (228)Ra levels varied from 6.2 ± 0.2 to 54.2 ± 1.7 Bq kg(-1). (137)Cs levels in Brazilian mushrooms are in accordance with the radioactive fallout in the Southern Hemisphere. The artificial and natural activities determined in this study were found to be below the maximum permissible levels as established by national legislation. Thus, these mushroom species can be normally consumed by the population without any apparent risks to human health. Copyright © 2012 Elsevier Ltd. All rights reserved.

  16. Coulomb Excitation of 78,80Se and the radioactive 84Se (N = 50) isotopes

    NASA Astrophysics Data System (ADS)

    Galindo-Uribarri, A.; Padilla-Rodal, E.; Garcia-Ruiz, R. F.; Allmond, J. M.; Batchelder, J. C.; Beene, J. R.; Lagergren, K. B.; Mueller, P. E.; Radford, D. C.; Stracener, D. W.; Urrego-Blanco, J. P.; Varner, R. L.; Yu, C.-H.

    2011-10-01

    Coulomb excitation is a purely electromagnetic excitation process of nuclear states due to the Coulomb field of two colliding nuclei. It is a very precise tool to measure excitation probabilities and provide insight on the collectivity of nuclear excitations and in particular on nuclear shapes. We have measured the B(E2) value of various nuclei in the mass A ~ 80 region using particle-gamma coincidences with the HyBall and Clarion arrays at HRIBF. The Coulomb excitation of various projectile-target combinations (ASe on 12C, 24Mg, 27Al and 50Ti) allow the use of consistency cross checks and the systematic study of isotopic and isotonic chains using both stable and radioactive nuclei under almost identical experimental conditions.We present new results for 78Se, 80Se and the radioactive nucleus 84Se (N = 50). Research sponsored by the Office of Nuclear Physics, U.S. Department of Energy and CONACyT Grant 103366.

  17. Enrico Fermi's Discovery of Neutron-Induced Artificial Radioactivity:The Recovery of His First Laboratory Notebook

    NASA Astrophysics Data System (ADS)

    Acocella, Giovanni; Guerra, Francesco; Robotti, Nadia

    . We give a short description of the discovery of the first experimental notebook of Enrico Fermi (1901-1954) on his researches during March and April of 1934 on neutron-induced artificial radioactivity, and we point out its relevance for a proper historical and conceptual understanding of those researches.

  18. An isotope dilution-precipitation process for removing radioactive cesium from wastewater.

    PubMed

    Rogers, Harold; Bowers, John; Gates-Anderson, Dianne

    2012-12-01

    A novel isotope dilution-precipitation method has been developed to remove cesium-137 from radioactive wastewater. The process involves adding stable cesium chloride to wastewater in order to raise the total cesium concentration, which then allows both the stable and radioactive cesium ions to be precipitated together using sodium tetraphenylborate. This process was investigated utilizing laboratory solutions to determine stable cesium dose rates, mixing times, effects of pH, and filtration requirements. Once optimized, the process was then tested on synthetic wastewater and aqueous low-level waste. Experiments showed the reaction to be very quick and stable in the pH range tested, 2.5-11.5. The wastewater may need to be filtered using a 0.45-μm filter, though ferric sulfate has been shown to promote coagulation and settling, thereby eliminating the necessity for filtration. This investigation showed that this isotope dilution-precipitation process can remove Cs-37 levels below the U.S. Department of Energy's (DOE) Derived Concentration Standard (DCS) of 3.0 × 10(-6) μCi/mL using a single dosage, potentially allowing the wastewater to be discharged directly to sanitary sewers.

  19. New laser setup for the selective isotope production and investigation in a laser ion source at the IRIS (Investigation of Radioactive Isotopes on Synchrocyclotron) facility

    SciTech Connect

    Barzakh, A. E.; Fedorov, D. V.; Ivanov, V. S.; Molkanov, P. L.; Panteleev, V. N.; Volkov, Yu. M.

    2012-02-15

    New laser installation for the resonance ionization spectroscopy in a laser ion source and for rare isotope production has been recently put into operation at the IRIS (Investigation of Radioactive Isotopes on Synchrocyclotron) facility (Petersburg Nuclear Physics Institute, Gatchina). This is a significant improvement of a previous target-laser ion source device of the IRIS mass-separator, working on-line with 1 GeV proton beam of PNPI (Petersburg Nuclear Physics Institute) synchrocyclotron. It makes possible for us to get the isobarically clean radioactive isotope beams of a great number of chemical elements. New laser setup provides the two- or three-resonance step ionization in the range of wavelength of 265-850 nm. The first results obtained at the laser setup for Tl isotopes are presented.

  20. Production of radioactive isotopes through cosmic muon spallation in KamLAND

    SciTech Connect

    Abe, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Kibe, Y.; Kishimoto, Y.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, M.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takemoto, Y.; Tamae, K.; Terashima, A.; Watanabe, H.

    2010-02-15

    Radioactive isotopes produced through cosmic muon spallation are a background for rare-event detection in nu detectors, double-beta-decay experiments, and dark-matter searches. Understanding the nature of cosmogenic backgrounds is particularly important for future experiments aiming to determine the pep and CNO solar neutrino fluxes, for which the background is dominated by the spallation production of {sup 11}C. Data from the Kamioka liquid-scintillator antineutrino detector (KamLAND) provides valuable information for better understanding these backgrounds, especially in liquid scintillators, and for checking estimates from current simulations based upon MUSIC, FLUKA, and GEANT4. Using the time correlation between detected muons and neutron captures, the neutron production yield in the KamLAND liquid scintillator is measured to be Y{sub n}=(2.8+-0.3)x10{sup -4} mu{sup -1} g{sup -1} cm{sup 2}. For other isotopes, the production yield is determined from the observed time correlation related to known isotope lifetimes. We find some yields are inconsistent with extrapolations based on an accelerator muon beam experiment.

  1. Review of Cyclotrons for the Production of Radioactive Isotopes for Medical and Industrial Applications

    NASA Astrophysics Data System (ADS)

    Schmor, Paul

    2011-02-01

    Radioactive isotopes are used in a wide range of medical, biological, environmental and industrial applications. Cyclotrons are the primary tool for producing the shorter-lived, proton-rich radioisotopes currently used in a variety of medical applications. Although the primary use of the cyclotron-produced short-lived radioisotopes is in PET/CT (positron emission tomography/computed tomography) and SPECT (single photon emission computed tomography) diagnostic medical procedures, cyclotrons are also producing longer-lived isotopes for therapeutic procedures as well as for other industrial and applied science applications. Commercial suppliers of cyclotrons are responding by providing a range of cyclotrons in the energy range of 3-70MeV for the differing needs of the various applications. These cyclotrons generally have multiple beams servicing multiple targets. This review article presents some of the applications of the radioisotopes and provides a comparison of some of the capabilities of the various current cyclotrons. The use of nuclear medicine and the number of cyclotrons supplying the needed isotopes are increasing. It is expected that there will soon be a new generation of small "tabletop" cyclotrons providing patient doses on demand.

  2. Study of the Production of Radioactive Isotopes through Cosmic Muon Spallation in KamLAND

    SciTech Connect

    KamLAND Collaboration; Abe, S.; Enomoto, S.; Furuno, K.; Gando, Y.; Ikeda, H.; Inoue, K.; Kibe, Y.; Kishimoto, Y.; Koga, M.; Minekawa, Y.; Mitsui, T.; Nakajima, K.; Nakajima, K.; Nakamura, K.; Nakamura, M.; Shimizu, I.; Shimizu, Y.; Shirai, J.; Suekane, F.; Suzuki, A.; Takemoto, Y.; Tamae, K.; Terashima, A.; Watanabe, H.; Yonezawa, E.; Yoshida, S.; Kozlov, A.; Murayama, H.; Busenitz, J.; Classen, T.; Grant, C.; Keefer, G.; Leonard, D. S.; McKee, D.; Piepke, A.; Banks, T. I.; Bloxham, T.; Detwiler, J. A.; Freedman, S. J.; Fujikawa, B. K.; Gray, F.; Guardincerri, E.; Hsu, L.; Ichimura, K.; Kadel, R.; Lendvai, C.; Luk, K.-B.; O'Donnell, T.; Steiner, H. M.; Winslow, L. A.; Dwyer, D. A.; Jillings, C.; Mauger, C.; McKeown, R. D.; Vogel, P.; Zhang, C.; Berger, B. E.; Lane, C. E.; Maricic, J.; Miletic, T.; Batygov, M.; Learned, J. G.; Matsuno, S.; Pakvasa, S.; Foster, J.; Horton-Smith, G. A.; Tang, A.; Dazeley, S.; Downum, K. E.; Gratta, G.; Tolich, K.; Bugg, W.; Efremenko, Y.; Kamyshkov, Y.; Perevozchikov, O.; Karwowski, H. J.; Markoff, D. M.; Tornow, W.; Heeger, K. M.; Piquemal, F.; Ricol, J.-S.; Decowski, M. P.

    2009-06-30

    Radioactive isotopes produced through cosmic muon spallation are a background for rare event detection in {nu} detectors, double-beta-decay experiments, and dark-matter searches. Understanding the nature of cosmogenic backgrounds is particularly important for future experiments aiming to determine the pep and CNO solar neutrino fluxes, for which the background is dominated by the spallation production of {sup 11}C. Data from the Kamioka Liquid scintillator Anti-Neutrino Detector (KamLAND) provides valuable information for better understanding these backgrounds, especially in liquid scintillator, and for checking estimates from current simulations based upon MUSIC, FLUKA, and Geant4. Using the time correlation between detected muons and neutron captures, the neutron production yield in the KamLAND liquid scintillator is measured to be (2.8 {+-} 0.3) x 10{sup -4} n/({mu} {center_dot} (g/cm{sup 2})). For other isotopes, the production yield is determined from the observed time correlation related to known isotope lifetimes. We find some yields are inconsistent with extrapolations based on an accelerator muon beam experiment.

  3. Ion beam production and study of radioactive isotopes with the laser ion source at ISOLDE

    NASA Astrophysics Data System (ADS)

    Fedosseev, Valentin; Chrysalidis, Katerina; Day Goodacre, Thomas; Marsh, Bruce; Rothe, Sebastian; Seiffert, Christoph; Wendt, Klaus

    2017-08-01

    At ISOLDE the majority of radioactive ion beams are produced using the resonance ionization laser ion source (RILIS). This ion source is based on resonant excitation of atomic transitions by wavelength tunable laser radiation. Since its installation at the ISOLDE facility in 1994, the RILIS laser setup has been developed into a versatile remotely operated laser system comprising state-of-the-art solid state and dye lasers capable of generating multiple high quality laser beams at any wavelength in the range of 210-950 nm. A continuous programme of atomic ionization scheme development at CERN and at other laboratories has gradually increased the number of RILIS-ionized elements. At present, isotopes of 40 different elements have been selectively laser-ionized by the ISOLDE RILIS. Studies related to the optimization of the laser-atom interaction environment have yielded new laser ion source types: the laser ion source and trap and the versatile arc discharge and laser ion source. Depending on the specific experimental requirements for beam purity or versatility to switch between different ionization mechanisms, these may offer a favourable alternative to the standard hot metal cavity configuration. In addition to its main purpose of ion beam production, the RILIS is used for laser spectroscopy of radioisotopes. In an ongoing experimental campaign the isotope shifts and hyperfine structure of long isotopic chains have been measured by the extremely sensitive in-source laser spectroscopy method. The studies performed in the lead region were focused on nuclear deformation and shape coexistence effects around the closed proton shell Z = 82. The paper describes the functional principles of the RILIS, the current status of the laser system and demonstrated capabilities for the production of different ion beams including the high-resolution studies of short-lived isotopes and other applications of RILIS lasers for ISOLDE experiments. This article belongs to the Focus on

  4. PRODUCTION AND TRANSPORT OF CARBON DIOXIDE IN A CONTAMINATED VADOSE ZONE: A STABLE AND RADIOACTIVE CARBON ISOTOPE STUDY

    EPA Science Inventory

    Analyses of soil gas compositions and stable and radioactive carbon isotopes in the vadose zone above an alluvial aquifer were conducted at an organic solvent disposal site in southeast Phoenix, AZ. The study investigated the source and movement of carbon dioxide above a plume of...

  5. PRODUCTION AND TRANSPORT OF CARBON DIOXIDE IN A CONTAMINATED VADOSE ZONE: A STABLE AND RADIOACTIVE CARBON ISOTOPE STUDY

    EPA Science Inventory

    Analyses of soil gas compositions and stable and radioactive carbon isotopes in the vadose zone above an alluvial aquifer were conducted at an organic solvent disposal site in southeast Phoenix, AZ. The study investigated the source and movement of carbon dioxide above a plume of...

  6. Applications of UThPb isotope systematics to the problems of radioactive waste disposal

    USGS Publications Warehouse

    Stuckless, J.S.

    1986-01-01

    mobility can be obtained through the use of isotopic studies. Such information can be extremely important in the search for favorable hosts for containment of radioactive waste. Rocks such as the Go??temar Granite have undergone considerable rock-water interaction, most of which occurred ??? 400 Myr. ago and little in recent times. Thus a search for zones that have experienced only a little interaction with water may provide a misleading prediction as to the ability of such zones to shield radioactive wastes from the modern biosphere. From an isotopic point of view, an ideal candidate for evaluation as a host rock for radioactive wastes would have the following characteristics: (1) a high ratio (> 2) of radiogenic to common Pb in order to optimize precision of the results; (2) a simple two-stage geologic history so that results could be interpreted without multiple working hypotheses; and (3) an originally high percentage (> 50%) of labile U so that the results would be highly sensitive to even small amount of rock-water interaction. These characteristics should produce rocks with marked radioactive disequilibrium in surface samples. The disequilibrium should grade to radioactive equilibrium with increasing depth until zones in which water has not circulated are found. Extensive regions of such zones must exist because UThPb systematics of most analyzed granitoids demonstrate closed-system behavior for almost all of their history except for their recent history in the near-surface environment. ?? 1986.

  7. Isotope tracers of organic carbon during artificial recharge

    SciTech Connect

    Davisson, M.L.

    1998-02-09

    This project developed an analytical technique for measuring the isotope abundance for 14C and 13C in total organic carbon (TOC) in order to test whether these measurements can trace TOC interaction with sedimentary material at the bottom of rivers and lakes, soils, and subsurface aquifer rocks.

  8. Detection of radioactive isotopes by using laser Compton scattered γ-ray beams

    NASA Astrophysics Data System (ADS)

    Hajima, R.; Kikuzawa, N.; Nishimori, N.; Hayakawa, T.; Shizuma, T.; Kawase, K.; Kando, M.; Minehara, E.; Toyokawa, H.; Ohgaki, H.

    2009-09-01

    Non-destructive detection and assay of nuclear materials is one of the most critical issues for both the management of nuclear waste and the non-proliferation of nuclear materials. We use laser Compton scattered (LCS) γ-ray beams and the nuclear resonance fluorescence (NRF) for the non-destructive detection of radioactive materials. Quasi-monochromatic and energy-tunable LCS γ-ray beams help improve the signal-to-noise ratio during NRF measurements. We developed the conceptual design of a high-flux γ-ray source with an energy-recovery linac, which produces a γ-ray beam at the flux of 1013 photons/s. In this paper, we discuss the execution of simulation studies using a Monte Carlo code, results of a proof-of-principle experiment for isotope detection, and the status of the development of LCS X-ray and γ-ray facilities.

  9. TRIμP — trapped radioactive isotopes: μicrolaboratories for fundamental physics

    NASA Astrophysics Data System (ADS)

    Jungmann, K.; Berg, G. P.; Dendooven, P.; Dermois, O.; Harakeh, M. N.; Hoekstra, R.; Morgenstern, R.; Rogachevskiy, A.; Sanchez-Vega, M.; Timmermans, R. G.; Willmann, L.; Wilschut, H. W.

    2003-04-01

    At the Kernfysisch Versneller Instituut (KVI) a new facility (TRIμP) is under development. It aims for producing a spectrum of radioactive isotopes in direct, inverse kiematics fusion and evaporation or fragmentation reactions with heavy ion beams from the superconducting cyclotron AGOR. The products will be slowed down and trapped for accurate measurements of fundamental symmetries and interactions in physics. The scientific focus of the local KVI research groups includes precision studies of nuclear β-decays through β-neutrino (recoil nucleus) momentum correlations in weak decays and searches for permanent electric dipole moments in heavy atomic systems. This research programme offers a large potential for discovering new physics or to limit parameters in models beyond standard theory significantly. The scientific approach chosen in TRIμP can be regarded as complementary to such high energy physics. The TRIμP facility in Groningen will be open for users worldwide.

  10. Isotopic labeling of mouse interferon by incorporation of radioactive amino acids during synthesis

    SciTech Connect

    DeMaeyer-Guignard, J.; Cachard, A.; DeMaeyer, E.

    1982-07-30

    Mouse interferon produced by C-243 cells induced with Newcastle disease virus was isotopically labeled by adding either (/sup 35/S)methionine or a /sup 14/C-labeled amino acid mixture to the culture medium. A method combining butyric acid and theophylline treatment and resulting in high interferon yields was used. Following purification by two-step affinity chromatography on poly(U) and antibody columns, the resulting material was analyzed on SDS-PAGE. The migration pattern of radioactivity and interferon coincided well and autoradiography revealed three major bands at migration distances corresponding, respectively, to 35, 28, and 22 K. Interferon represented 3.8% of all (/sup 35/S)methionine-labeled proteins and 2.6% of all /sup 14/C-amino acid-labeled proteins released into the medium.

  11. Neutron flux measurement using activated radioactive isotopes at the Baksan underground scintillation telescope

    NASA Astrophysics Data System (ADS)

    Kochkarov, M. M.; Alikhanov, I. A.; Boliev, M. M.; Dzaparova, I. M.; Novoseltseva, R. V.; Novoseltsev, Yu. F.; Petkov, V. B.; Volchenko, V. I.; Volchenko, G. V.; Yanin, A. F.

    2016-11-01

    Preliminary results of a neutron background measurement at the Baksan underground scintillation telescope (BUST) are presented. The external planes of the BUST are fully covered with standard scintillation detectors shielding the internal planes and suppressing thus background events due to cosmogenic and local radioactivity. The shielded internal planes were used as target for the neutron flux registration. The experimental method is based on the delayed coincidences between signals from any of the BUST counters. It is assumed that the first signal is due to inelastic interaction of a neutron with the organic scintillator, while the second signal comes from the decay of an unstable radioactive isotope formed when the fast neutron interacts with the 12C nuclei. Using the Monte-Carlo method (GEANT4) we also simulated propagation of neutrons through a layer of scintillator. The experimentally found muon induced neutron flux is j =1.3 -0.3 +0.7 ×10-10cm-2s-1 for neutron energies E ≥ 22MeV, which is in a qualitative agreement with similar measurements of other underground laboratories as well as with predictions of the GEANT4.

  12. Hydrogen isotope alteration of normal alkanes during artificial maturation experiments

    NASA Astrophysics Data System (ADS)

    Wang, C.; Eley, Y.; Oakes, A.; Hren, M. T.

    2016-12-01

    Hydrogen isotopes of normal alkanes provide a record of past climate, hydrocarbon source and migration, and thermal history. Numerous authors have investigated the preservation potential of organic compounds during burial diagenesis and developed a range of molecular indicators of thermal maturity. A key uncertainty in application of organic biomarkers for paleoenvironmental work is how the δD values of individual molecular compounds changes during burial heating and thermal cracking. Studies suggest that n-alkanes are unlikely to exchange hydrogen at modest temperatures (below 150°C) over geologic time, however there is still debate over the potential for alteration of primary isotopic signatures due to the combined effect of exchange and cracking of more complex molecules. We conducted a suite of heating experiments in ambient air and oxygen-free systems using pure alkane mixtures and natural soil extracts to evaluate the preservation potential of the hydrogen isotopic composition of both short (nC20) carbon chain n-alkanes. Our data show that for pure mixtures, there is a positive shift in the δD of long carbon chains during heating of up to 12‰ and a negative shift in short chains of up to 28‰. Experiments with natural sediment extracts show 2H enrichment of long carbon chains during heating in both ambient air and oxygen free systems, and at temperatures below 150°C. These changes are accompanied by shifts in the carbon preference and average chain length. Experimental data show that there is potential for 2H/1H alteration of long-carbon chain normal alkanes during shallow burial, however these changes rarely exceed 10-15‰ before compounds are degraded to quantities below useful abundances for isotope measurements. A potentially significant result is that low temperature alteration of organics within sediments can shift the average chain length, particularly in the presence of oxygen. Thus, lithology and gas permeability may play an important role in

  13. Artificial radioactivity in environmental media (air, rainwater, soil, vegetation) in Austria after the Fukushima nuclear accident.

    PubMed

    Steinhauser, Georg; Merz, Stefan; Hainz, Dieter; Sterba, Johannes H

    2013-04-01

    Several environmental media in Austria were monitored for artificial radionuclides released during the Fukushima nuclear accident. Air (up to 1.2 mBq/m(3) particulate (131)I) and rainwater (up to 5.2 Bq/L (131)I) proved to be the media best suited for the environmental monitoring, allowing also a temporal resolution of the activity levels. Significant regional differences in the wet deposition of (131)I with rain could be observed within the city of Vienna during the arrival of the contaminated air masses. Forward-trajectory analysis supported the hypothesis that the contaminated air masses coming from the northwest changed direction to northeast over Northern Austria, leading to a strong activity concentration gradient over Vienna. In the course of the environmental monitoring of the Fukushima releases, this phenomenon-significant differences of (131)I activity concentrations in rainwater on a narrow local scale (8.1 km)-appears to be unique. Vegetation (grass) was contaminated with (131)I and/or (137)Cs at a low level. Soil (up to 22 Bq/kg (137)Cs) was only affected by previous releases (nuclear weapon tests, Chernobyl). Here, also significant local differences can be observed due to different deposition rates during the Chernobyl accident. The effective ecological half-lives of (137)Cs in soil were calculated for four locations in Austria. They range from 7 to 30 years. No Austrian sample investigated herein exceeded the detection limit for (134)Cs; hence, the Fukushima nuclear accident did not contribute significantly to the total radiocesium inventory in Austrian environmental media. The levels of detected radioactivity were of no concern for public health.

  14. Using isotopes for design and monitoring of artificial recharge systems

    USGS Publications Warehouse

    Contributors: Hendriksson, N.; Kulongoski, J.T.; Massmann, G.; Newman, B.

    2013-01-01

    Over the past years, the IAEA has provided support to a number of Member States engaged in the implementation of hydrological projects dealing with the design and monitoring of artificial recharge ( A R ) systems, primarily situated in arid and semiarid regions. AR is defined as any engineered system designed to introduce water to, and store water in, underlying aquifers. Aquifer storage and recovery (ASR) is a specific type of AR used with the purpose of increasing groundwater resources. Different water management strategies have been tested under various geographical, hydrological and climatic regimes. However, the success of such schemes cannot easily be predicted, since many variables need to be taken into account in the early stages of every AR project.

  15. Production of neutron-rich Ca, Sn, and Xe isotopes in transfer-type reactions with radioactive beams

    SciTech Connect

    Adamian, G. G.; Antonenko, N. V.; Lacroix, D.

    2010-12-15

    The production cross sections of neutron-rich isotopes {sup 52,54,56,58,60}Ca, {sup 136,138,140,142}Sn, and {sup 146,148,150,152}Xe are predicted for future experiments in the diffusive multinucleon transfer reactions {sup 86,90,92,94}Kr, {sup 124,130,132,134}Sn, {sup 136,140,142,146}Xe, and {sup 138,144,146}Ba+{sup 48}Ca with stable and radioactive beams at incident energies close to the Coulomb barrier. Because of the small cross sections, the production of neutron-rich isotopes requires the optimal choice of projectile-target combinations and bombarding energies.

  16. Artificial neutrino source based on the {sup 37}Ar isotope

    SciTech Connect

    Barsanov, V. I.; Dzhanelidze, A. A.; Zlokazov, S. B.; Kotelnikov, N. A.; Markov, S. Yu.; Selin, V. V.; Shakirov, Z. N.; Abdurashitov, D. N.; Veretenkin, E. P.; Gavrin, V. N.; Gorbachev, V. V.; Ibragimova, T. V.; Kalikhov, A. V.; Mirmov, I. N. Shikhin, A. A.; Yants, V. E.; Khomyakov, Yu. S.; Cleveland, B. T.

    2007-02-15

    In April 2004, a neutrino source was produced by irradiating a 330-kg piece of pressed calcium oxide at the fast-neutron reactor BN-600 (Zarechny, Russia) for six months. The {sup 37}Ar isotope was obtained via the (n, {alpha}) reaction on {sup 40}Ca, and {sup 37}Ar was extracted from an aqueous solution of nitric acid in which the solid target was dissolved. After that, {sup 37}Ar was purified and sealed into a capsule. This source was used to measure the neutrino-capture rate in metalic gallium for neutrinos from {sup 37}Ar decay, which have an energy close to that of the main line of solar {sup 7}Be neutrinos (863 keV). The target of the SAGE Gallium-Germanium Neutrino Telescope was irradiated by using this source at the Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences). The source activity was measured by several methods during its production, in the course of irradiation, and after its completion. The weighted mean of the activity for six measurements was 409 {+-} 2 kCi at the beginning of irradiation of the gallium target (04:00 Moscow time, 30.04.2004). The scatter in the activity values obtained by different methods does not exceed 5%.

  17. Artificial neutrino source based on the 37Ar isotope

    NASA Astrophysics Data System (ADS)

    Barsanov, V. I.; Dzhanelidze, A. A.; Zlokazov, S. B.; Kotelnikov, N. A.; Markov, S. Yu.; Selin, V. V.; Shakirov, Z. N.; Abdurashitov, D. N.; Veretenkin, E. P.; Gavrin, V. N.; Gorbachev, V. V.; Ibragimova, T. V.; Kalikhov, A. V.; Mirmov, I. N.; Shikhin, A. A.; Yants, V. E.; Khomyakov, Yu. S.; Cleveland, B. T.

    2007-02-01

    In April 2004, a neutrino source was produced by irradiating a 330-kg piece of pressed calcium oxide at the fast-neutron reactor BN-600 (Zarechny, Russia) for six months. The 37Ar isotope was obtained via the (n, α) reaction on 40Ca, and 37Ar was extracted from an aqueous solution of nitric acid in which the solid target was dissolved. After that, 37Ar was purified and sealed into a capsule. This source was used to measure the neutrino-capture rate in metalic gallium for neutrinos from 37Ar decay, which have an energy close to that of the main line of solar 7Be neutrinos (863 keV). The target of the SAGE Gallium-Germanium Neutrino Telescope was irradiated by using this source at the Baksan Neutrino Observatory (Institute for Nuclear Research, Russian Academy of Sciences). The source activity was measured by several methods during its production, in the course of irradiation, and after its completion. The weighted mean of the activity for six measurements was 409 ± 2 kCi at the beginning of irradiation of the gallium target (04:00 Moscow time, 30.04.2004). The scatter in the activity values obtained by different methods does not exceed 5%.

  18. Ion source developments for the production of radioactive isotope beams at TRIUMF

    SciTech Connect

    Ames, F. Bricault, P.; Heggen, H.; Kunz, P.; Lassen, J.; Mjøs, A.; Raeder, S.; Teigelhöfer, A.

    2014-02-15

    At the ISAC facility at TRIUMF radioactive ions are produced by bombarding solid targets with up to 100 μA of 500 MeV protons. The reaction products have to diffuse out of the hot target into an ion source. Normally, singly charged ions are extracted. They can be transported either directly to experiments or via an ECR charge state breeder to a post accelerator. Several different types of ion sources have to be used in order to deliver a large variety of rare isotope beams. At ISAC those are surface ion sources, forced electron beam arc discharge (FEBIAD) ion sources and resonant laser ionization sources. Recent development activities concentrated on increasing the selectivity for the ionization to suppress isobaric contamination in the beam. Therefore, a surface ion rejecting resonant laser ionization source (SIRLIS) has been developed to suppress ions from surface ionization. For the FEBIAD ion source a cold transfer line has been introduced to prevent less volatile components from reaching the ion source.

  19. Sub-micron alignment for nuclear emulsion plates using low energy electrons caused by radioactive isotopes

    NASA Astrophysics Data System (ADS)

    Miyamoto, S.; Ariga, A.; Fukuda, T.; Kazuyama, M.; Komatsu, M.; Nakano, T.; Niwa, K.; Sato, O.; Takahashi, S.

    2007-06-01

    Nuclear emulsion plates are employed in three-dimensional charged particle detectors that have sub-micron position resolution over 1 m2 with no dead space and no dead time. These detectors are suitable for the study of short-lived particle decays, and direct detection of neutrino interactions of all flavors. Typically emulsion plates are used in a stacked structure. Precise alignment between plates is required for physics analysis. The most accurate alignment method is to use tracks passing through the emulsion plates. The accuracy is about 0.2 μm. However, in an experiment with low track density alignment accuracy decreases to 20 μm because of plate distortion and it becomes more difficult to perform the analysis. This paper describes a new alignment method between emulsion plates by using trajectories of low energy electrons originating from environmental radioactive isotopes. As a trial emulsion plates were exposed to β-rays and γ-rays from K40. The trajectories which passed through emulsion layers were detected by a fully automated emulsion readout system. Using this method, the alignment between emulsion plates is demonstrated to be sub-micron. This method can be applied to many nuclear emulsion experiments. For example, the location of neutrino interaction vertices in the OPERA experiment can benefit from this new technique.

  20. Possibility of wine dating using the natural Pb-210 radioactive isotope.

    PubMed

    Hubert, Ph; Pravikoff, M S; Gaye, J

    2015-04-01

    To control the authenticity of an old wine without opening the bottle, we developed a few years ago a method based on the measurement of the (137)Cs activity. However, for recent vintages, the (137)Cs activity drops to far too low values (most of the time less than 10 mBq/L for a 10-year-old wine) for this method to perform correctly. In this paper we examine the possibility to date wines using the natural radio-element (210)Pb which has a 22-year period. This new method we propose implies the opening of the bottle and the follow-on destruction of the wine itself, which means that it can only be used for investigating non-expensive bottles or wine lots where there are multiple bottles of the same provenance. Uncertainties on the resulting (210)Pb radioactivity values are large, up to more than 50%, mainly due to local atmospheric variations, which prevents us to carry out precise dating. However it can be used to discriminate between an old wine (pre-1952) and a young wine (past-1990), an information that cannot be obtained with the other techniques based on other isotopes ((137)Cs, (14)C or tritium).

  1. Measurement of natural and 137Cs radioactivity concentrations at Izmit Bay (Marmara Sea), Turkey

    NASA Astrophysics Data System (ADS)

    Öksüz, I.; Güray, R. T.; Özkan, N.; Yalçin, C.; Ergül, H. A.; Aksan, S.

    2016-03-01

    In order to determine the radioactivity level at Izmit Bay Marmara Sea, marine sediment samples were collected from five different locations. The radioactivity concentrations of naturally occurring 238U, 232Th and 40K isotopes and also that of an artificial isotope 137Cs were measured by using gamma-ray spectroscopy. Preliminary results show that the radioactivity concentrations of 238U and 232Th isotopes are lower than the average worldwide values while the radioactivity concentrations of the 40K are higher than the average worldwide value. A small amount of 137Cs contamination, which might be caused by the Chernobyl accident, was also detected.

  2. Travel Times of Water Derived from Three Naturally Occurring Cosmogenic Radioactive Isotopes

    NASA Astrophysics Data System (ADS)

    Visser, Ate; Thaw, Melissa; Deinhart, Amanda; Bibby, Richard; Esser, Brad

    2017-04-01

    Hydrological travel times are studied on scales that span six orders of magnitude, from daily event water in stream flow to pre-Holocene groundwater in wells. Groundwater vulnerability to contamination, groundwater surface water interactions and catchment response are often focused on "modern" water that recharged after the introduction of anthropogenic tritium in precipitation in 1953. Shorter residence times are expected in smaller catchments, resulting in immediate vulnerability to contamination. We studied a small (4.6 km2) alpine (1660-2117 m) catchment in a Mediterranean climate (8 ˚ C, 1200 mm/yr) in the California Sierra Nevada to assess subsurface storage and investigate the response to the recent California drought. We analyzed a combination of three cosmogenic radioactive isotopes with half-lives varying from 87 days (sulfur-35), 2.6 years (sodium-22) to 12.3 years (tritium) in precipitation and stream samples. Tritium samples (1 L) are analyzed by noble gas mass spectrometry after helium-3 accumulation. Samples for sulfur-35 and sodium-22 are collected by processing 20-1000 L of water through an anion and cation exchange column in-situ. Sulfur-35 is analyzed by liquid scintillation counting after chemical purification and precipitation. Sodium-22 is analyzed by gamma counting after eluting the cations into a 4L Marinelli beaker. Monthly collected precipitation samples show variability of deposition rate for tritium and sulfur-35. Sodium-22 levels in cumulative yearly precipitation samples are consistent with recent studies in the US and Japan. The observed variability of deposition rates complicates direct estimation of stream water age fractions. The level and variability of tritium in monthly stream samples indicate a mean residence time on the order of 10 years and only small contributions of younger water during high flow conditions. Estimates of subsurface storage are in agreement with estimates from geophysical studies. Detections of sodium-22

  3. Nuclear structure from radioactive decay

    SciTech Connect

    Wood, J.L.

    1990-09-30

    This report discusses the nuclear structure of the following isotopes as a result of radioactive decays: neutron-deficient iridium isotopes; neutron-deficient platinum isotopes; neutron-deficient gold isotopes; neutron-deficient mercury isotopes; neutron-deficient thallium isotopes; neutron-deficient lead isotopes; neutron-deficient promethium isotopes; and neutron-deficient samarium isotopes.

  4. Quantification of four artificial sweeteners in Finnish surface waters with isotope-dilution mass spectrometry.

    PubMed

    Perkola, Noora; Sainio, Pirjo

    2014-01-01

    The artificial sweeteners sucralose (SCL), acesulfame (ACS), saccharin (SAC), and cyclamate (CYC) have been detected in environmental waters in Europe and North America. Higher environmental levels are expected in view of the increasing consumption of these food additives. In this study, an isotope-dilution mass spectrometry (IDMS) LC-MS/MS method was developed and validated for quantifying the four artificial sweeteners in boreal lakes (n = 3) and rivers (n = 12). The highest concentrations of ACS, SAC, CYC and SCL were 9,600, 490, 210 and 1000 ng/L, respectively. ACS and SAC were detected in all studied samples, and CYC and SCL in 98% and 56% of the samples. Seasonal trends of ACS and SAC were observed in some rivers. ACS and SCL concentrations in rivers correlated linearly with population equivalents of the wastewater treatment plants in the catchment areas, whereas SAC and CYC concentrations depend more on the source.

  5. Neutrino Interactions with Matter by a New Neutrino Source From the Isotope Radioactive Decay Produced by the Proton Accelerator

    NASA Astrophysics Data System (ADS)

    Shin, Jae Won; Park, Tae-Sun; Kajino, Toshitaka; Cheoun, Myung-Ki

    A new neutrino source for future's neutrino experiments is suggested in this work. Unstable isotope, 27Si, can be produced when 27Al target is bombarded by 15 MeV proton beams. Through the decay of the 27Si, a new electron-neutrino source in the 0-5.0 MeV energy range is obtained. Production of the neutrino source is studied by using GEANT4 code with JENDL-4.0/HE. For radioactive decay processes, we use "G4RadioactiveDecay" model based on the Evaluated Nuclear Structure Data File (ENSDF). As for the detection system of the new neutrino source, we evaluate reaction or event rates for available radiochemical detectors and LENA type scintillator detector.

  6. Uptake of radioactive and stable Co and Zn isotopes by barley plants under mixed radioactive and chemical contamination of soils

    NASA Astrophysics Data System (ADS)

    Kruglov, S. V.; Lavrent'eva, G. V.; Pivovarova, Yu. A.; Anisimov, V. S.

    2010-03-01

    The effect of Co and Zn on the accumulation of 60Co and 65Zn by plants was studied in experiments with growing barley on a soddy-podzolic soil and a chernozem containing the radionuclide and increasing concentrations (from the background level to a high degree of contamination) of the corresponding metal. The root uptake of 60Co was directly related to the soil contamination with Co and its accumulation in the plants, while an inverse relationship was observed between the activity of 65Zn in the plants and the content of Zn in the soil. It was concluded that the transfer of the radionuclide into the plants under mixed radioactive and chemical contamination depended, on the one hand, on the mobile reserve of the stable nuclide in the soil and the solid phase potential to release its ions into the soil solution and, on the other hand, on the requirement of the plants for this element and the uptake rate of its ions by the roots from the solution.

  7. The origin of the background radioactive isotope 127Xe in the sample of Xe enriched in 124Xe

    NASA Astrophysics Data System (ADS)

    Gavrilyuk, Yu. M.; Gangapshev, A. M.; Kazalov, V. V.; Kuzminov, V. V.; Panasenko, S. I.; Ratkevich, S. S.; Tekueva, D. A.; Yakimenko, S. P.

    2017-01-01

    The results of investigation of 127Xe radioactive isotope production in the xenon sample enriched in 124Xe, 126Xe, 128Xe are presented. The isotope is supposed to be the source of the background events in the low-background experiment on search for 2 K-capture of 124Xe. In this work we consider two channels of 127Xe production: the neutron knock-out from 128Xe nucleus by cosmogenic muons and the neutron capture by 126Xe nucleus. For the first channel the upper limit of the cross section of 127Xe production was found to be σ ≤ 0.007 × 10-24 cm2 at 95% C.L. For the second channel the value obtained for the cross section was found to be equal to σ = (2.74 ± 0.4) × 10-24 cm2, which coincides well, within the statistical error, with reference value.

  8. B(E2)↑ Measurements for Radioactive Neutron-Rich Ge Isotopes: Reaching the N=50 Closed Shell

    NASA Astrophysics Data System (ADS)

    Padilla-Rodal, E.; Galindo-Uribarri, A.; Baktash, C.; Batchelder, J. C.; Beene, J. R.; Bijker, R.; Brown, B. A.; Castaños, O.; Fuentes, B.; del Campo, J. Gomez; Hausladen, P. A.; Larochelle, Y.; Lisetskiy, A. F.; Mueller, P. E.; Radford, D. C.; Stracener, D. W.; Urrego, J. P.; Varner, R. L.; Yu, C.-H.

    2005-03-01

    The B(E2;0+1→2+1) values for the radioactive neutron-rich germanium isotopes 78,80Ge and the closed neutron shell nucleus 82Ge were measured at the HRIBF using Coulomb excitation in inverse kinematics. These data allow a study of the systematic trend between the subshell closures at N=40 and 50. The B(E2) behavior approaching N=50 is similar to the trend observed for heavier isotopic chains. A comparison of the experimental results with a shell model calculation demonstrates persistence of the N=50 shell gap and a strong sensitivity of the B(E2) values to the effective interaction.

  9. Natural and artificial radioactivity distribution in soil of Fars Province, Iran.

    PubMed

    Faghihi, R; Mehdizadeh, S; Sina, S

    2011-04-01

    Fars province is a large populated large province located in the southwest of Iran. This work presents a study of natural and radioactivity levels in soil samples of this province. For this purpose, 126 samples were gathered from different regions of the province and analysed by gamma spectroscopy to quantify radioactivity concentrations of radionuclides using a high-purity germanium detector and spectroscopy system. The results of this investigation show the average concentrations of 271 ± 28 Bq kg(-1), 6.37 ± 0.5 Bq kg(-1), 14.9 ± 0.9 Bq kg(-1) and 26.3 ± 1.9 Bq kg(-1) for (40)K, (137)Cs, (232)Th and (238)U in soil, respectively. Finally, baseline maps were established for the concentrations of each of the radionuclides in different regions. The absorbed dose rate and the annual effective dose (AED) were also calculated for the radionuclides according to the guidelines of UNSCEAR 2000. The average AED from the radioactivity content of soil in this province was found to be 39.9 ± 1.8 μSv.

  10. Radioactive pollution: Ocean environments. (Latest citations from Oceanic abstracts). Published Search

    SciTech Connect

    Not Available

    1994-04-01

    This bibliography contains citations concerning radioactive pollution of the marine environment. Distrubutions of radionuclides that indicate artificial radioactive contamination are discussed including iodine-131, various uranium isotopes, Cesium-137, Cobalt-60, Strontium-90, Ruthenium-160, and plutonium isotopes. Ecosystems considered include coral reefs and atolls, planktonic zones in the open ocean, salt marshes, estuaries, coastal waters, and the Mediterranean Sea. Sources of radioactive contamination examined include atomic bomb blasts, fossil fuel combustion, radioactive waste disposal, and nuclear accidents. Experimental simulation of radionuclide transport in marine biota is included. (Contains a minimum of 161 citations and includes a subject term index and title list.)

  11. Radioactive pollution: Oean environments. (Latest citations from Oceanic abstracts). Published Search

    SciTech Connect

    1995-02-01

    This bibliography contains citations concerning radioactive pollution of the marine environment. Distrubutions of radionuclides that indicate artificial radioactive contamination are discussed including iodine-131, various uranium isotopes, Cesium-137, Cobalt-60, Strontium-90, Ruthenium-160, and plutonium isotopes. Ecosystems considered include coral reefs and atolls, planktonic zones in the open ocean, salt marshes, estuaries, coastal waters, and the Mediterranean Sea. Sources of radioactive contamination examined include atomic bomb blasts, fossil fuel combustion, radioactive waste disposal, and nuclear accidents. Experimental simulation of radionuclide transport in marine biota is included. (Contains a minimum of 168 citations and includes a subject term index and title list.)

  12. Radioactive pollution: Ocean environments. (Latest citations from Oceanic abstracts). Published Search

    SciTech Connect

    1996-05-01

    This bibliography contains citations concerning radioactive pollution of the marine environment. Distrubutions of radionuclides that indicate artificial radioactive contamination are discussed including iodine-131, various uranium isotopes, Cesium-137, Cobalt-60, Strontium-90, Ruthenium-160, and plutonium isotopes. Ecosystems considered include coral reefs and atolls, planktonic zones in the open ocean, salt marshes, estuaries, coastal waters, and the Mediterranean Sea. Sources of radioactive contamination examined include atomic bomb blasts, fossil fuel combustion, radioactive waste disposal, and nuclear accidents. Experimental simulation of radionuclide transport in marine biota is included. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  13. Radioactive pollution: Ocean environments. (Latest citations from Oceanic abstracts). Published Search

    SciTech Connect

    1997-07-01

    This bibliography contains citations concerning radioactive pollution of the marine environment. Distrubutions of radionuclides that indicate artificial radioactive contamination are discussed including iodine-131, various uranium isotopes, Cesium-137, Cobalt-60, Strontium-90, Ruthenium-160, and plutonium isotopes. Ecosystems considered include coral reefs and atolls, planktonic zones in the open ocean, salt marshes, estuaries, coastal waters, and the Mediterranean Sea. Sources of radioactive contamination examined include atomic bomb blasts, fossil fuel combustion, radioactive waste disposal, and nuclear accidents. Experimental simulation of radionuclide transport in marine biota is included. (Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  14. First measurement of radioactive isotope production through cosmic-ray muon spallation in Super-Kamiokande IV

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Abe, K.; Haga, Y.; Hayato, Y.; Ikeda, M.; Iyogi, K.; Kameda, J.; Kishimoto, Y.; Miura, M.; Moriyama, S.; Nakahata, M.; Nakajima, T.; Nakano, Y.; Nakayama, S.; Orii, A.; Sekiya, H.; Shiozawa, M.; Takeda, A.; Tanaka, H.; Tomura, T.; Wendell, R. A.; Irvine, T.; Kajita, T.; Kametani, I.; Kaneyuki, K.; Nishimura, Y.; Richard, E.; Okumura, K.; Labarga, L.; Fernandez, P.; Gustafson, J.; Kachulis, C.; Kearns, E.; Raaf, J. L.; Stone, J. L.; Sulak, L. R.; Berkman, S.; Nantais, C. M.; Tanaka, H. A.; Tobayama, S.; Goldhaber, M.; Carminati, G.; Griskevich, N. J.; Kropp, W. R.; Mine, S.; Renshaw, A.; Smy, M. B.; Sobel, H. W.; Takhistov, V.; Weatherly, P.; Ganezer, K. S.; Hartfiel, B. L.; Hill, J.; Hong, N.; Kim, J. Y.; Lim, I. T.; Himmel, A.; Li, Z.; Scholberg, K.; Walter, C. W.; Wongjirad, T.; Ishizuka, T.; Tasaka, S.; Jang, J. S.; Learned, J. G.; Matsuno, S.; Smith, S. N.; Friend, M.; Hasegawa, T.; Ishida, T.; Ishii, T.; Kobayashi, T.; Nakadaira, T.; Nakamura, K.; Oyama, Y.; Sakashita, K.; Sekiguchi, T.; Tsukamoto, T.; Suzuki, A. T.; Takeuchi, Y.; Yano, T.; Hirota, S.; Huang, K.; Ieki, K.; Kikawa, T.; Minamino, A.; Nakaya, T.; Suzuki, K.; Takahashi, S.; Fukuda, Y.; Choi, K.; Itow, Y.; Suzuki, T.; Mijakowski, P.; Frankiewicz, K.; Hignight, J.; Imber, J.; Jung, C. K.; Li, X.; Palomino, J. L.; Wilking, M. J.; Yanagisawa, C.; Ishino, H.; Kayano, T.; Kibayashi, A.; Koshio, Y.; Mori, T.; Sakuda, M.; Kuno, Y.; Tacik, R.; Kim, S. B.; Okazawa, H.; Choi, Y.; Nishijima, K.; Koshiba, M.; Suda, Y.; Totsuka, Y.; Yokoyama, M.; Bronner, C.; Hartz, M.; Martens, K.; Marti, Ll.; Suzuki, Y.; Vagins, M. R.; Martin, J. F.; de Perio, P.; Konaka, A.; Chen, S.; Wilkes, R. J.; Super-Kamiokande Collaboration

    2016-01-01

    Cosmic-ray-muon spallation-induced radioactive isotopes with β decays are one of the major backgrounds for solar, reactor, and supernova relic neutrino experiments. Unlike in scintillator, production yields for cosmogenic backgrounds in water have not been exclusively measured before, yet they are becoming more and more important in next generation neutrino experiments designed to search for rare signals. We have analyzed the low-energy trigger data collected at Super-Kamiokande IV in order to determine the production rates of 12B, 12N, 16N, 11Be, 9Li, 8He, 9C, 8Li, 8B, and 15C. These rates were extracted from fits to time differences between parent muons and subsequent daughter β 's by fixing the known isotope lifetimes. Since >9Li can fake an inverse-beta-decay reaction chain via a β +n cascade decay, producing an irreducible background with detected energy up to a dozen MeV, a dedicated study is needed for evaluating its impact on future measurements; the application of a neutron tagging technique using correlated triggers was found to improve this 9Li measurement. The measured yields were generally found to be comparable with theoretical calculations, except the cases of the isotopes 9Li / 8B and 9Li.

  15. Radioactive isotopes in atmospheric aerosols over Russia and the Sea of Japan following nuclear accident at Fukushima Nr. 1 Daiichi Nuclear Power Station in March 2011.

    PubMed

    Neroda, Andrey S; Mishukov, Vasily F; Goryachev, Vladimir A; Simonenkov, Denis V; Goncharova, Anna A

    2014-04-01

    Artificial radionuclides, such as iodine-131 ((131)I), cesium-134 ((134)Cs), and cesium-137 ((137)Cs), as well as natural isotopes of beryllium-7 ((7)Be) and potassium-40 ((40)K) have been registered in atmospheric aerosols over Vladivostok selected from 11 March to 17 June 2011. Additionally, (134)Cs and (137)Cs were detected in atmospheric aerosols over Tomsk selected from 16 March to 17 June 2011. Artificial radionuclides were also discovered in atmospheric wet depositions sampled in Vladivostok from 3 to 17 May 2011. Moreover, these radionuclides have been registered in atmospheric aerosols over the sea surface of the Sea of Japan selected from 3 to 31 May 2011 during an expedition of the "Nadezhda" sailing ship. From 18 March to 15 April, an increase in concentrations of atmospheric aerosols over Vladivostok from 108.8 to 321.5 μg/m(3) has been registered. It was accompanied by increased activity concentrations of (134)Cs, (137)Cs, and the (131)I. During the period from 18 March to 15 April, activity concentrations of (137)Cs and (134)Cs in atmospheric aerosols increased 100 times compared with the minimum detectable concentration (MDC) level and peaked in the weekly sample gathered from 8 to 15 April (145.0 and 105.3 μBq/m(3), respectively). Variability of concentrations of natural isotopes of (7)Be and (40)K was not greater than 1 order of magnitude throughout the sampling period. Maximal values of (137)Cs and (134)Cs concentrations (1,281.5 ± 141 and 384.4 ± 42.3 μBq/m(3), respectively) in Tomsk were reached in samples taken from 1 to 2 April. For the atmospheric aerosol samples from the Sea of Japan, the largest concentration of (131)I (392.3 ± 215.7 μBq/m(3)) was detected from 13 to 19 May, while all other samples had much lower concentration values. Synoptic analysis of back trajectories movement of air masses showed that the radioactive cloud came to Vladivostok from the regions of Siberia and northeastern part of China. Synoptic

  16. Stable isotopes in aquatic food web of an artificial lagoon in the Hangzhou Bay, China

    NASA Astrophysics Data System (ADS)

    Quan, Weimin; Shi, Liyan; Chen, Yaqu

    2010-05-01

    Stable isotope values, δ13C and δ15N, were determined for four primary producers and 19 dominant consumers in a small artificial lagoon located in Hangzhou Bay. Based on these results the major pathways for energy flow and trophic structure of the artificial lagoon ecosystem were characterized. The mean δ13C values for the 19 consumers ranged from -22.99‰ to -14.24‰. Apart from so-iny mullet Liza haematocheila, the other 18 consumers had intermediate δ13C values between those of epibenthic microalgae and particulate organic matter (POM). The results of a multiple source linear mixing model (IsoSource model) indicated that 50% or more of the organic carbon in the tissues of most consumers was derived from epibenthic microalgae. This indicated that these primary producers were the main food source fueling the lagoon food web. The mean δ15N values for the 19 consumers varied between 4.93‰ and 12.97‰ and indicated four trophic levels in the lagoon. Four macroinvertebrates and zooplankton represented the primary consumers, whilst the other 14 consumers occupied the secondary and tertiary consumer levels. The 19 consumers were divided into three trophic guilds (detritivores/suspension feeders, omnivores and carnivores).

  17. Stable nitrogen isotope ratios in wet and dry nitrate deposition collected with an artificial tree

    SciTech Connect

    Garten Jr, Charles T

    1996-02-01

    Amounts of dry NO{sub 3}-N deposition and N isotope ratios in wet and dry NO{sub 3}-N deposition have been simultaneously determined by examining differences between precipitation collected by open funnels and throughfall collected beneath an artificial Christmas tree. Samples were collected in a forest clearing on Walker Branch Watershed, near Oak Ridge, Tennessee. From mid-summer to early autumn, NO{sub 3}-N fluxes beneath the artificial tree were always greater than those measured in precipitation indicating the tree's effectiveness as a passive collector of dry NO{sub 3}-N deposition. Dry NO{sub 3}-N deposition averaged 60 {+-} 9% of total (wet and dry) deposition. The mean ({+-} SD) calculated {delta}{sup 15}N value for NO{sub 3}-N in dry deposition was + 5.6 {+-} 2.1{per_thousand} (n = 6 sampling periods ranging from 4 to 15 days). On average, this was {approx} 6{per_thousand} heavier than measured {delta}{sup 15}N values for NO{sub 3}-N in precipitation. The calculated {delta}{sup 15}N value for NO{sub 3}-N in dry deposition was consistent with that expected if NO{sub x} precursors to HNO{sub 3} vapor (the major constituent of dry deposition at this site) originated principally from coal combustion.

  18. Stable nitrogen isotope ratios in wet and dry nitrate deposition collected with an artificial tree

    NASA Astrophysics Data System (ADS)

    Garten, Charles T., Jr.

    1996-02-01

    Amounts of dry NO3-N deposition and N isotope ratios in wet and dry NO3-N deposition have been simultaneously determined by examining differences between precipitation collected by open funnels and throughfall collected beneath an artificial Christmas tree. Samples were collected in a forest clearing on Walker Branch Watershed, near Oak Ridge, Tennessee. From mid-summer to early autumn, NO3-N fluxes beneath the artificial tree were always greater than those measured in precipitation indicating the tree's effectiveness as a passive collector of dry NO3-N deposition. Dry NO3-N deposition averaged 60±9% of total (wet and dry) deposition. The mean (±SD) calculated δ15N value for NO3-N in dry deposition was+5.6±2.1‰ (n= 6 sampling periods ranging from 4 to 15days). On average, this was ≈ 6‰ heavier than measured δ15N values for NO3-N in precipitation. The calculated δ15N value for NO3-N in dry deposition was consistent with that expected if NOx precursors to HNO3 vapor (the major constituent of dry deposition at this site) originated principally from coal combustion.

  19. Artificial radioactivity in fuel peat and peat ash in Finland after the Chernobyl accident

    SciTech Connect

    Mustonen, R.A.; Reponen, A.R.; Jantunen, M.J.

    1989-04-01

    The accident at the Chernobyl nuclear power plant in April 1986 caused very uneven deposition of radionuclides in Finland. The deposited radionuclides were found in relatively high concentrations in fuel peat and especially in peat ash because a thin surface layer of peat-production bogs was extracted as fuel peat soon after the fallout occurred. Concentrations of artificial radionuclides in fuel peat and peat ash were measured at six peat-fired power plants in Finland throughout the heating season 1986-87. Concentrations of /sup 137/Cs in composite peat samples varied between 30 and 3600 Bq kg-1 dry weight and in ash samples between 600 and 68,000 Bq kg-1. High concentrations in peat ash caused some restrictions to the utilization of peat ash for various purposes.

  20. Use of radium isotopes to determine the age and origin of radioactive barite at oil-field production sites

    USGS Publications Warehouse

    Zielinski, R.A.; Otton, J.K.; Budahn, J.R.

    2001-01-01

    Radium-bearing barite (radiobarite) is a common constituent of scale and sludge deposits that form in oil-field production equipment. The barite forms as a precipitate from radium-bearing, saline formation water that is pumped to the surface along with oil. Radioactivity levels in some oil-field equipment and in soils contaminated by scale and sludge can be sufficiently high to pose a potential health threat. Accurate determinations of radium isotopes (226Ra+228Ra) in soils are required to establish the level of soil contamination and the volume of soil that may exceed regulatory limits for total radium content. In this study the radium isotopic data are used to provide estimates of the age of formation of the radiobarite contaminant. Age estimates require that highly insoluble radiobarite approximates a chemically closed system from the time of its formation. Age estimates are based on the decay of short-lived 228Ra (half-life=5.76 years) compared to 226Ra (half-life=1600 years). Present activity ratios of 228Ra/226Ra in radiobarite-rich scale or highly contaminated soil are compared to initial ratios at the time of radiobarite precipitation. Initial ratios are estimated by measurements of saline water or recent barite precipitates at the site or by considering a range of probable initial ratios based on reported values in modern oil-field brines. At sites that contain two distinct radiobarite sources of different age, the soils containing mixtures of sources can be identified, and mixing proportions quantified using radium concentration and isotopic data. These uses of radium isotope data provide more description of contamination history and can possibly address liability issues. Copyright ?? 2000 .

  1. Radioactivity of cigarettes and the importance of (210)Po and thorium isotopes for radiation dose assessment due to smoking.

    PubMed

    Kubalek, Davor; Serša, Gregor; Štrok, Marko; Benedik, Ljudmila; Jeran, Zvonka

    2016-05-01

    Tobacco and tobacco smoke are very complex mixtures. In addition to various chemical and organic compounds they also contain natural radioactive elements (radionuclides). In this work, the natural radionuclide activity concentrations ((234)U, (238)U, (228)Th, (230)Th, (232)Th, (226)Ra, (210)Pb and (210)Po) of nine different cigarette samples available on the Slovenian market are reported. In addition to (210)Po, the transfer of thorium isotopes from a cigarette to a smoker's body and lungs have been determined for the first time. Cigarette smoke and exhaled air from smokers' lungs were collected from volunteer smokers (C-4 brand) to determinate what quantity of (210)Po and thorium isotopes is transferred from the tobacco to the smoker's lungs. Cigarette ash and smoked filters were also collected and analysed. Among the determined isotopes, (210)Pb and (210)Po showed the highest activity concentrations. During the smoking of one cigarette approximately 22% of (210)Po (and presumably its predecessor (210)Pb), 0.6% of (228)Th, 24% of (230)Th, and 31% of (232)Th are transferred from the cigarette and retained in the smoker's body. The estimated annual effective dose for smokers is 61 μSv/year from (210)Po; 9 μSv/year from (210)Pb; 6 μSv/year from (228)Th; 47 μSv/year from (230)Th, and 37 μSv/year from (232)Th. These results show the importance of thorium isotopes in contributing to the annual effective dose for smoking. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Isotopic tracing of the outflow during artificial rain-on-snow event

    NASA Astrophysics Data System (ADS)

    Juras, Roman; Pavlásek, Jirka; Vitvar, Tomáš; Šanda, Martin; Holub, Jirka; Jankovec, Jakub; Linda, Miloslav

    2016-10-01

    The frequency of rain-on-snow (ROS) occurrence is increasing and this natural phenomenon is beginning to play an important role in temperate climate regions. Present knowledge of outflow generation mechanisms and rainwater dynamics during ROS is still insufficient. The study introduces a combined method of artificial ROS, isotopic tracing and energy balance to partition the event rainwater and the pre-event non-rainwater in the outflow. A rainfall simulator and water enriched with deuterium were used for identifying event rainwater and pre-event non-rainwater during an ROS event. The ROS experiment was conducted in the Krkonoše Mountains in the Czech Republic. An experimental snow block consisting of ripe and isothermal snow was sprayed with deuterium enriched water. The outflow from the snowpack was continuously monitored to gain quantitative and qualitative information about outflow water. The isotopic deuterium content was further analysed from the samples by means of laser spectroscopy in order to separate the hydrograph components. The deuterium content was also analysed from the snow samples gathered before and after the experiment to identify the retention of event rainwater in the snowpack. Isotopic hydrograph separation revealed that although high rain intensity was applied, the event rainwater represented one half (52.7%) of the total outflow volume. The ripe snowpack retained about one third of the rainwater input (33.6%). Significant changes in the outflowing water quality can therefore be expected during ROS events. This experiment also shows that rainwater during ROS firstly pushes-out the non-rainwater and then contributes to the outflow. These results show that the presented technique allows us to gain sufficient information about rainwater dynamics during ROS.

  3. Deformation in the neutron-deficient rare earth isotopes: Radioactive decay scheme studies in the neodymium, promethium, and samarium isotopes

    SciTech Connect

    Breitenbach, J.B.

    1993-12-31

    Several experiments were performed at the UNISOR isotope separator facility at HHIRF at the Oak Ridge National Laboratory on the {beta}{sup +}/EC decay of neutron-deficient rare earth isotopes. Data for the decay chain {sup 133}Sm {yields} {sup 133}Pm {yields} {sup 133}Nd was obtained, consisting of multiscaled spectra of {gamma} rays, X rays, and conversion electrons, as well as {gamma}{gamma}t, X{gamma}t, e{gamma}t and eXt coincidences. Gamma rays associated with the decay of {sup 133}Sm and {sup 133}Pm were observed for the first time. The decay of a new low-spin (1/2) isomeric state, with a half life of about 70 sec was established for {sup 133}Nd. The level schemes for {sup 133}Nd and {sup 133}Pr were constructed. An M3 and two E1 isomers are established in {sup 133}Nd and an E3 isomer is confirmed in {sup 133}Pr. The energy level systematics for the nuclear region bounded by Z {ge} 58 and N {le} 78 is discussed. Theoretical interpretations are based on the particle-plus-triaxial rotor model calculations. In the framework of these calculations, the {beta}{sub 2} deformation is moderate for these nuclei ({beta}{sub 2} {approx} 0.20-0.25). A sudden onset of strong deformation is not observed, in contrast with the theoretical predictions by Leander and Moeller [Lea82].

  4. A kinematic-based methodology for radiological protection: Runoff analysis to calculate the effective dose for internal exposure caused by ingestion of radioactive isotopes

    NASA Astrophysics Data System (ADS)

    Sasaki, Syota; Yamada, Tadashi; Yamada, Tomohito J.

    2014-05-01

    We aim to propose a kinematic-based methodology similar with runoff analysis for readily understandable radiological protection. A merit of this methodology is to produce sufficiently accurate effective doses by basic analysis. The great earthquake attacked the north-east area in Japan on March 11, 2011. The system of electrical facilities to control Fukushima Daiichi nuclear power plant was completely destroyed by the following tsunamis. From the damaged reactor containment vessels, an amount of radioactive isotopes had leaked and been diffused in the vicinity of the plant. Radiological internal exposure caused by ingestion of food containing radioactive isotopes has become an issue of great interest to the public, and has caused excessive anxiety because of a deficiency of fundamental knowledge concerning radioactivity. Concentrations of radioactivity in the human body and internal exposure have been studied extensively. Previous radiologic studies, for example, studies by International Commission on Radiological Protection(ICRP), employ a large-scale computational simulation including actual mechanism of metabolism in the human body. While computational simulation is a standard method for calculating exposure doses among radiology specialists, these methods, although exact, are too difficult for non-specialists to grasp the whole image owing to the sophistication. In this study, the human body is treated as a vessel. The number of radioactive atoms in the human body can be described by an equation of continuity, which is the only governing equation. Half-life, the period of time required for the amount of a substance decreases by half, is only parameter to calculate the number of radioactive isotopes in the human body. Half-life depends only on the kinds of nuclides, there are no arbitrary parameters. It is known that the number of radioactive isotopes decrease exponentially by radioactive decay (physical outflow). It is also known that radioactive isotopes

  5. Quenching of neutron spectroscopic factors of radioactive carbon isotopes with knockout reactions within a wide energy range

    NASA Astrophysics Data System (ADS)

    Wen, Chao; Xu, Yi-Ping; Pang, Dan-Yang; Ye, Yan-Lin

    2017-05-01

    The quenching factors of one-neutron spectroscopic factors, which are ratios of theoretical to experimental one-neutron removal cross sections, are studied for the carbon isotopes 15-19C, with 12C and 9Be targets within incident energies from around 50 to 900 MeV/nucleon. The resulting values of quenching factors do not show strong energy dependence within such an energy range. The average values of the these quenching factors agree well with the systematics in [J.A. Tostevin and A. Gade, Phys. Rev. C, 90 057602 (2014)], which was established for a large set of radioactive nuclei with different masses below 305 MeV/nucleon. Supported by National Natural Science Foundation of China (1275018, U1432247) and National Key Research and Development Program (2016YFA0400502)

  6. Distribution of natural and artificial radioactivity in soils, water and tuber crops.

    PubMed

    Darko, Godfred; Faanu, Augustine; Akoto, Osei; Acheampong, Akwasi; Goode, Eric Jude; Gyamfi, Opoku

    2015-06-01

    Activity concentrations of radionuclides in water, soil and tuber crops of a major food-producing area in Ghana were investigated. The average gross alpha and beta activities were 0.021 and 0.094 Bq/L, respectively, and are below the guidelines for drinking water and therefore not expected to pose any significant health risk. The average annual effective dose due to ingestion of radionuclide in water ranged from 20.08 to 53.45 μSv/year. The average activity concentration of (238)U, (232)Th, (40)K and (137)Cs in the soil from different farmlands in the study area was 23.19, 31.10, 143.78 and 2.88 Bq/kg, respectively, which is lower than world averages. The determined absorbed dose rate for the farmlands ranged from 23.63 to 50.51 nGy/year, which is within worldwide range of 18 to 93 nGy/year. The activity concentration of (238)U, (232)Th, (40)K and (137)Cs in cassava ranges from 0.38 to 6.73, 1.82 to 10.32, 17.65 to 41.01 and 0.38 to 1.02 Bq/kg, respectively. Additionally, the activity concentration of (238)U, (232)Th, (40)K and (137)Cs in yam also ranges from 0.47 to 4.89, 0.93 to 5.03, 14.19 to 35.07 and 0.34 to 0.89 Bq/kg, respectively. The average concentration ratio for (238)U, (232)Th and (40)K in yam was 0.12, 0.11 and 0.17, respectively, and in cassava was 0.11, 0.12 and 0.2, respectively. None of the radioactivity is expected to cause significant health problems to human beings.

  7. The abundance of the radioactive isotope Al-26 in galactic cosmic rays

    NASA Technical Reports Server (NTRS)

    Wiedenbeck, M. E.

    1983-01-01

    Satellite observations of the isotopic composition of aluminum in low energy cosmic rays (E/M = 200 MeV/amu) have been used to determine the abundance of the unstable isotope Al-26 (T1/2 = 0.87 Myr). The observed abundance ratio, Al-26/Al-27 = 0.036 (+0.037, -0.022), is in good agreement with previous balloon observations and yields a cosmic ray confinement time consistent with values based on the abundance of Be-10.

  8. Radioactive isotope production for medical applications using Kharkov electron driven subcritical assembly facility.

    SciTech Connect

    Talamo, A.; Gohar, Y.; Nuclear Engineering Division

    2007-05-15

    Kharkov Institute of Physics and Technology (KIPT) of Ukraine has a plan to construct an accelerator driven subcritical assembly. The main functions of the subcritical assembly are the medical isotope production, neutron thereby, and the support of the Ukraine nuclear industry. Reactor physics experiments and material research will be carried out using the capabilities of this facility. The United States of America and Ukraine have started collaboration activity for developing a conceptual design for this facility with low enrichment uranium (LEU) fuel. Different conceptual designs are being developed based on the facility mission and the engineering requirements including nuclear physics, neutronics, heat transfer, thermal hydraulics, structure, and material issues. Different fuel designs with LEU and reflector materials are considered in the design process. Safety, reliability, and environmental considerations are included in the facility conceptual design. The facility is configured to accommodate future design improvements and upgrades. This report is a part of the Argonne National Laboratory Activity within this collaboration for developing and characterizing the subcritical assembly conceptual design. In this study, the medical isotope production function of the Kharkov facility is defined. First, a review was carried out to identify the medical isotopes and its medical use. Then a preliminary assessment was performed without including the self-shielding effect of the irradiated samples. Finally, more detailed investigation was carried out including the self-shielding effect, which defined the sample size and irradiation location for producing each medical isotope. In the first part, the reaction rates were calculated as the multiplication of the cross section with the unperturbed neutron flux of the facility. Over fifty isotopes were considered and all transmutation channels are used including (n,{gamma}), (n,2n), (n,p), and ({gamma},n). In the second part

  9. Extended methods using thick-targets for nuclear reaction data of radioactive isotopes

    NASA Astrophysics Data System (ADS)

    Ebata, Shuichiro; Aikawa, Masayuki; Imai, Shotaro

    2017-09-01

    The nuclear transmutation is a technology to dispose of radioactive wastes. However, we do not have enough basic data for its developments, such as thick-target yields (TTY) and the interaction cross sections for radioactive material. We suggest two methods to estimate the TTY using inverse kinematics and to obtain the excitation function of the interaction cross sections which is named the thick-target transmission (T3) method. We deduce the energy-dependent conversion relation between the TTYs of the original system and its inverse kinematics, which can be replaced to a constant coefficient in the high energy region. Furthermore we show the usefulness of the T3 method to investigate the excitation function of the 12C + 27Al reaction in the simulation.

  10. Measure post-bloodmeal dispersal of mosquitoes and duration of radioactivity by using the isotope ³²P.

    PubMed

    Zhang, Chongxing; Cheng, Peng; Liu, Bo; Shi, Guihong; Wang, Huaiwei; Liu, Lijuan; Guo, Xiuxia; Ren, Huiqing; Gong, Maoqing

    2014-01-01

    The radioactive isotope (32)P-labeled disodium phosphate (Na₂H(32)PO₄) was injected via the jugular vein into a cow kept in a shed in Maozhuang Village, Cao Township of Shanxian County, China. Over the following 5 d, mosquitoes feeding on the cow were captured at distances up to 400 m to determine dispersal distance. The duration of radioactivity in the cow and marked mosquitoes was 10 d. The results showed that after blood feeding, Anopheles sinensis and Culex tritaeniorhynchus temporarily rested in the cattle shed and then flew outdoors. In contrast, Culex pipiens pallens remained in the cattle shed after feeding. These findings confirmed that local An. sinensis and Cx. tritaeniorhynchus were partially endophilic and tended to rest out of doors, whereas Cx. pipiens pallens was endophilic. For marked An. sinensis and Cx. tritaeniorhynchus, there was a significant tendency for dispersal to be in a northeast and east direction, probably because of the presence of heavy shading by an agricultural field, a small river for mosquito oviposition sites, and locations downwind from the blood source. The furthest flight distances for An. sinensis and Cx. tritaeniorhynchus were 210 and 240 m; therefore, control of these mosquitoes should include resting places indoors and outdoors within a radius of 250 m from confirmed cases. © The Author 2014. Published by Oxford University Press on behalf of the Entomological Society of America.

  11. Survey on radiation safety management (RSM) among Korean radiation workers who operate radiation generators or handle radioactive isotopes.

    PubMed

    Ryu, Young-Hwan; Cho, Jae-Hwan; Dong, Kyung-Rae; Chung, Woon-Kwan; Lee, Jong-Woong; Choi, Eun-Jin

    2014-01-01

    This study examined the knowledge, attitudes, and behaviors of radiation workers to radiation safety management (RSM) using survey questionnaires. Radiation workers are those who handle radiation generators, radioactive isotopes, and other radioactive materials for industrial uses. The survey was distributed to 861 radiation workers between 1 August to 5 September 2011. A knowledge of, awareness of, attitude toward, and behaviors related to RSM were analyzed by comparing the means and standard deviations. Both the knowledge and awareness of RSM among radiation workers were high. Although all questions about the awareness of RSM were answered correctly, there were also many negative responses. All questions regarding the attitude of radiation workers toward RSM were answered correctly, and their attitude toward and awareness of RSM were high. Overall, the results demonstrated that safety management is not taken seriously in many cases, highlighting the need for proper education in the future to raise awareness among radiation workers. Furthermore, it is important to establish a foundation for the efficient use of radiation based on the continuous management of radiation workers.

  12. Distribution of Corpuscular and Lysed Antigens Labeled with Radioactive Isotopes in a Sensitized Organism

    DTIC Science & Technology

    1974-10-04

    obtained in our experiments on a brucellosis model (Shaposhnikov, 1967). FTD-MT-24-1695-7L 1 /.1_ When using soluble proteins and not microboes as the...comparing the distribution of the labeled corpuscular al.d soluble antigen, using one form of animals and one model of allergic sensitization. The...the control animlals , regardless of which antigen was administered to them. 4.* The removal of the radioactive decay products of the antigens took

  13. Nuclear structure from radioactive decay

    SciTech Connect

    Wood, J.L.

    1991-09-30

    This report discusses nuclear structure from radioactive decay of the following: Neutron-Deficient Iridium Isotopes; Neutron-Deficient Platinum Isotopes; Neutron-Deficient Gold Isotopes; Neutron-Deficient Mercury Isotopes; Neutron-Deficient Thallium Isotopes; Neutron-Deficient Lead Isotopes; Neutron-Deficient Samarium Isotopes; Neutron-Deficient Promethium Isotopes; Neutron-Deficient Neodymium Isotopes; and Neutron-Deficient Praseodymium Isotopes. Also discussed are Nuclear Systematics and Models.

  14. Ultrasensitive detection of radioactive cesium isotopes using a magneto-optical trap.

    SciTech Connect

    Di Rosa, M. D.; Crane, S. G.; Kitten, J. J.; Taylor, W. A.; Vieira, D. J.; Zhao, X.

    2002-01-01

    We report the first magneto-optical trapping of mdioactive {sup 135}Cs and {sup 137}Cs and a promising means for detecting these isotopes to ullrasensilive lcvels by a system coupling the magneto-optical trap (MOT) to a mass separator. The mass separator efficiently delivers a 20 kV ion beam of either isotope into a quartzcube MOT cell having in one corner a small-diameter Zr foil, on which the ion beam is focused and into which the ions are implantetl. Inductive heating of thc foil releases {approx}45% of the implanted atoms into a MOT that uses large diameter beams and a dry-film coating to capture 3% of the released vapor. MOT fluorescence signals were found to increasc linearly with the number of foil-implanted atoms over a range of 10{sup 4} to 10{sup 7} in trapped-atom number. The measured slope of MOT signal versus number implanted was equal in the case each isotope to within 4%, signifying our ability to measure {sup 137}Cs/{sup 135}Cs ratios to within 4%. The isotopic selectivities of the mass separator and MOT combine to suppress interfering signal from {sup 133}Cs by a factor of greater than 5 x 10{sup 12} in the case of detecting {sup 135}Cs or {sup 137}Cs. Our present sample detection sensitivity is one million atoms.

  15. Radioactive pollution: ocean environments. January 1974-May 1989 (Citations from Oceanic Abstracts). Report for January 1974-May 1989

    SciTech Connect

    Not Available

    1989-06-01

    This bibliography contains citations concerning radioactive pollution of the marine environment. Distributions of radionuclides indicative of artificial radioactive contamination are discussed including iodine-131, various uranium isotopes, cesium-137, cobalt-60, strontium-90, ruthenium-160, and plutonium isotopes. Ecosystems considered include coral reefs and atolls, planktonic zones in the open ocean, salt marshes, estuaries, coastal waters, and the Mediterranean Sea. Sources of radioactive contamination examined include atomic bomb blasts, fossil-fuel combustion, radioactive waste disposal, and nuclear accidents. Experimental simulation of radionuclide transport in marine biota is included. (Contains 108 citations fully indexed and including a title list.)

  16. TRIμP — A radioactive isotope trapping facility at KVI

    NASA Astrophysics Data System (ADS)

    Berg, G. P. A.; Dendooven, P.; Dermois, O.; Harakeh, M. N.; Hoekstra, R.; Hoekstra, S.; Jungmann, K.; Kopecky, S.; Kravchuk, V.; Morgenstern, R.; Rogachevskiy, A.; Willmann, L.; Wilschut, H. W.

    2003-06-01

    TRIμP, a new research facility to produce and trap rare and short-lived isotopes for high precision physics experiments is under design and construction at KVI. This facility makes use of the existing super-conducting cyclotron and the infrastructure of the laboratory. To be able to study a large variety of heavy ions a new dual function magnetic separator has been developed. Details of the separator and the status of the project will be presented.

  17. Radioactive and radiogenic isotopes in sediments from Cooper Creek, Western Arnhem Land.

    PubMed

    Frostick, A; Bollhöfer, A; Parry, D; Munksgaard, N; Evans, K

    2008-03-01

    Protection of the environment post-mining is a key objective of rehabilitation, especially where runoff and erosion from rehabilitated mine sites could potentially lead to contamination of the surrounding land and watercourses. As part of an overall assessment of the success of rehabilitation at the former Nabarlek uranium (U) mine, an appraisal of stable lead (Pb) isotopes, radionuclides and trace metals within sediments and soils was conducted to determine the off site impacts from a spatial and temporal perspective. The study found localised areas on and adjacent to the site where soils had elevated levels of trace metals and radionuclides. Lead isotope ratios are highly radiogenic in some samples, indicating the presence of U-rich material. There is some indication that erosion products with more radiogenic Pb isotope ratios have deposited in sediments downstream of the former ore body. However, there is no indication that the radiogenic erosion products found on the mine site at present have significantly contaminated sediments further downstream of Cooper Creek.

  18. Environmental pollutant isotope measurements and natural radioactivity assessment for north Tushki area, south western desert, Egypt.

    PubMed

    Sroor, A; Afifi, S Y; Abdel-Haleem, A S; Salman, A B; Abdel-Sammad, M

    2002-09-01

    Natural radioactive materials under certain conditions can reach hazardous radiological levels. The natural radionuclide (238U, 232Th, 40K) contents of rock samples at various locations in the North Tushki area were investigated using gamma-spectrometric analysis. Estimates of the measured radionuclide content have been made for the absorbed dose rate of gamma radiation. The equivalent radium (Req) and the external hazard index (Hex) which resulted from the natural radionuclides in soil are also calculated and tabulated. The studied samples have been collected from various rock exposures in the North Tushki area. The distribution of major oxides, U and Th were studied. It is found that the enrichment and depletion of the major oxides are mainly due to the effect of hydrothermal alteration, which caused mobility of some major oxides, which increases some elements and decreases others. It is important to mention that the study area is far from the development region of the Tushki project and is only a local hazard. Therefore, additional regional studies of the Tushki Project area should be under taken to explore any unexpected environmental hazard due to the high concentration of the radioactive elements, which have been observed at its north boundary.

  19. Source term estimation and the isotopic ratio of radioactive material released from the WIPP repository in New Mexico, USA.

    PubMed

    Thakur, P

    2016-01-01

    After almost 15 years of operations, the Waste Isolation Pilot Plant (WIPP) had one of its waste drums breach underground as a result of a runaway chemical reaction in the waste it contained. This incident occurred on February 14, 2014. Moderate levels of radioactivity were released into the underground air. A small portion of the contaminated underground air also escaped to the surface through the ventilation system and was detected approximately 1 km away from the facility. According to the source term estimation, the actual amount of radioactivity released from the WIPP site was less than 1.5 mCi. The highest activity detected on the surface was 115.2 μBq/m(3) for (241)Am and 10.2 μBq/m(3) for (239+240)Pu at a sampling station located 91 m away from the underground air exhaust point and 81.4 μBq/m(3) of (241)Am and 5.8 μBq/m(3) of (239+240)Pu at a monitoring station located approximately 1 km northwest of the WIPP facility. The dominant radionuclides released were americium and plutonium, in a ratio that matches the content of the breached drum. Air monitoring across the WIPP site intensified following the first reports of radiation detection underground to determine the extent of impact to WIPP personnel, the public, and the environment. In this paper, the early stage monitoring data collected by an independent monitoring program conducted by the Carlsbad Environmental Monitoring & Research Center (CEMRC) and an oversight monitoring program conducted by the WIPP's management and operating contractor, the Nuclear Waste Partnership (NWP) LLC were utilized to estimate the actual amount of radioactivity released from the WIPP underground. The Am and Pu isotope ratios were measured and used to support the hypothesis that the release came from one drum identified as having breached that represents a specific waste stream with this radionuclide ratio in its inventory. This failed drum underwent a heat and gas producing reaction that overpowered its vent and

  20. Measurements of radioactive and stable sulfur isotopes at Mt. Everest and its geochemical implications

    NASA Astrophysics Data System (ADS)

    Lin, M.; Thiemens, M. H.; Zhang, Q.; Li, C.; Kang, S.; Hsu, S. C.; Zhang, Z.; Su, L.

    2015-12-01

    The Himalayas were recently identified as a global hotspot for deep stratosphere-to-troposphere transport (STT) during spring [1]. Although STT transport in this region may play a vital role in tropospheric chemistry, the hydrological cycle and aquatic ecosystems in Asia, there is no direct measurement of a specific chemical stratospheric tracer to verify and evaluate its possible impact. Here, cosmogenic 35S tracer (half-life: ~87 days) produced in the stratosphere was measured for the first time in surface snow and river runoff samples collected at Mt. Everest in April 2013 using a low-noise liquid scintillation spectroscopy [2]. Strikingly, we find extraordinarily high concentrations of 35S in these samples (>10 times higher than the southern Tibetan Plateau), verifying the Himalayas as a gateway of springtime STT. In light of this, two studies were conducted: a) Measurements of 35SO2 and 35SO42- at the southern Tibetan Plateau reveals that the oxidative life time of SO2 is reduced to 2.1 days under the influence of aged stratospheric air masses from the Himalayas. A concept box model for estimating the influence of STT on surface O3 using 35S tracer is proposed. b) Quadruple stable sulfur isotopes in a sediment core (~250 years) from the Gokyo Lake (the world's highest freshwater lake) [3] near Mt. Everest are being measured to investigate the possible impact of STT on sulfur budget at the Himalayas. The absence of sulfide suggests that bacterial sulfate reduction may be negligible in this lake. Enrichment of uranium (EF ≈ 10) in 20th century samples highlights the impact of atmospheric deposition. S-isotope sulfate anomalies are not found (∆33S and ∆36S ≈ 0‰), implying that sulfate in this lake may be mainly contributed by eolian dust or derived from rock. This is also supported by the low enrichments of most trace elements (EF ≈ 1). Rare earth elements will be used to assist in identifying the potential sources and interpreting the variation of

  1. Radiogenic and Radioactive Isotopic Evidence for a Dynamic Residence Time of the Athabasca Glacier Subglacial Water

    NASA Astrophysics Data System (ADS)

    Arendt, C. A.; Aciego, S.; Sims, K. W.; Aarons, S. M.

    2011-12-01

    Little is known about the time it takes precipitation, input of water from reservoirs, surface melt, and basal melt to migrate to the base of a glacier and discharge. Previous work on the residence time of subglacial water has proven to be either inconclusive or inconsistent. Our research will address the primary subglacial water questions; the flux of subglacial water correlates directly to the mass balance of a glacier but what role does subglacial water storage play in that mass balance? Can we determine residence time of subglacial water? And, how variable is residence time seasonally and on longer time scales? The regional focus of our research is the Athabasca Glacier, part of the Columbia Icefield located in Jasper National Park, Alberta, Canada. Uranium-series (U-series) dating methods based on the ingrowth of daughter isotopes from parents (234U, 230Th and 222Rn from the primary parent 238U) have been used to study the residence time of aquifer systems. Here we show the feasibility of applying these techniques to subglacial water. Samples were collected over two 25-day field periods to account for hydrological and chemical fluctuations between the onset of melt and peak melt. Daily physical observations, 222Rn concentrations (from a Durridge RAD7), conductivity, total alkalinity, pH, maximum velocity, and discharge measurements were taken. Fifty daily 10-40L subglacial water and filtered sediment samples were collected and filtered at our collection site in the main channel at the toe of the Athabasca Glacier. The 238U /234U and 87Sr/86Sr isotopic compositions and U, Th, and Sr concentrations of the filtrate and captured sediments is pending. We will extrapolate the residence time of the water based on the accumulation of 234U and 230Th in our samples from alpha decay, which can be coupled to a radiometric timescale. Given that the 238U /234U and 234U/230Th isotopic composition of subglacial water is dependent on recoil and sediment dissolution processes

  2. Quantifying Atmospheric Fallout of Fukushima-derived Radioactive Isotopes in the Hawaiian Islands

    NASA Astrophysics Data System (ADS)

    McKenzie, Trista; Dulai, Henrietta

    2016-04-01

    On March 11, 2011, several reactors at the Fukushima Dai-ichi Nuclear Power Plant suffered damage and released the radioisotopes iodine-131, cesium-134, and cesium-137 into the atmosphere. A week later, these isotopes were detected in aerosols over the state of Hawaii and in milk samples analyzed from the Big Island. Because the detected levels were significantly below levels of health concern, the state did not attempt to quantify the deposition of these nuclides on the islands. This study estimated the magnitude of atmospheric fallout of cesium and iodine, and examined the patterns of cesium wet deposition with precipitation observed in March 2011. Mushroom and soil samples were collected along precipitation gradients on Oahu and the island of Hawaii and analyzed for cesium isotopes using gamma spectrometry. Fukushima-derived fallout was differentiated from historic nuclear weapons testing fallout by the presence of Cs-134, which has a shorter half-life of 2.06 years and the fact that Cs-134 and 137 were released from the severed power plant nearly in parity. We found that Fukushima-derived cesium was present in both mushrooms and soil and the soil inventories ranged 2.2-60.9 Bq/m2 for Cs-137 and 16.1-445.8 Bq/m2 for I-131. Additionally, we found that Fukushima-derived cesium inventories in soils were correlated with precipitation gradients. This research confirmed and quantified the presence of Fukushima-derived fallout in Hawaii, however the activities detected were orders of magnitude lower than fallout associated with the nuclear weapons testing in the Pacific.

  3. Analysis of gaseous-phase stable and radioactive isotopes in the unsaturated zone, Yucca Mountain, Nevada

    SciTech Connect

    Yang, I.C.; Haas, H.H.; Weeks, E.P.; Thorstenson, D.C.

    1985-12-31

    The Nevada Nuclear Waste Storage Investigations Project of the US Department of Energy provides that agency with data for evaluating volcanic tuff beneath Yucca Mountain, Nevada, to determine its suitability for a potential repository of high-level radioactive waste. Thickness of the unsaturated zone, which consists of fractured, welded and nonwelded tuff, is about 1640 to 2460 feet (500 to 750 meters). One question to be resolved is an estimate of minimum ground-water traveltime from the disturbed zone of the potentail repository to the accessible environment. Another issue is the potential for diffusive or convective gaseous transport of radionuclides from an underground facility in the unsaturated zone to the accessible environment. Gas samples were collected at intervals to a depth of 1200 feet from the unsaturated zone at Yucca Mountain, Nevada. Samples were analyzed for major atmospheric gases; carbon dioxide in the samples was analyzed for carbon-14 activity and for {delta}2!{sup 3}C; water vapor in the samples was analyzed for deuterium and oxygen-18. These data could provide insight into the nature of unsaturated zone transport processes. 15 refs., 4 figs., 4 tabs.

  4. Isotopic separation of snowmelt runoff during an artificial rain-on-snow event

    NASA Astrophysics Data System (ADS)

    Juras, Roman; Pavlasek, Jirka; Šanda, Martin; Jankovec, Jakub; Linda, Miloslav

    2013-04-01

    Rain-on-snow events are common phenomenon in the climate conditions of central Europe, mainly during the spring snowmelt period. These events can cause serious floods in areas with seasonal snow. The snowpack hit by rain is able to store a fraction of rain water, but runoff caused by additional snowmelt also increases. Assessment of the rainwater ratio contributing to the outflow from the snowpack is therefore critical for discharge modelling. A rainfall simulator and water enriched by deuterium were used for the study of rainwater behaviour during an artificial rain-on-snow event. An area of 1 m2 of the snow sample, which was 1.2 m deep, consisting of ripped coarse-grained snow, was sprayed during the experiment with deuterium enriched water. The outflow from the snowpack was measured and samples of outflow water were collected. The isotopic content of deuterium was further analyzed from these samples by means of laser spectroscopy for the purpose of hydrograph separation. The concentration of deuterium in snow before and after the experiment was also investigated. The deuterium enriched water above the natural concentration of deuterium in snowpack was detected in the outflow in 7th minute from start of spraying, but the significant increase of deuterium concentration in outflow was observed in 19th minute. The isotopic hydrograph separation estimated, that deuterium enriched rainwater became the major part (> 50% volumetric) of the outflow in 28th minute. The culmination of the outflow (1.23 l min-1) as well as deuterium enriched rainwater fraction (63.5%) in it occurred in 63th minute, i.e. right after the end of spraying. In total, 72.7 l of deuterium enriched water was sprayed on the snowpack in 62 minutes. Total volume of outflow (after 12.3 hours) water was 97.4 l, which contained 48.3 l of deuterium enriched water (i.e. 49.6 %) and 49.1 l (50.4 %) of the melted snowpack. The volume of 24.4 l of deuterium enriched spray-water was stored in the snowpack. The

  5. ASTROPHYSICAL SHRAPNEL: DISCRIMINATING AMONG NEAR-EARTH STELLAR EXPLOSION SOURCES OF LIVE RADIOACTIVE ISOTOPES

    SciTech Connect

    Fry, Brian J.; Fields, Brian D.; Ellis, John R.

    2015-02-10

    We consider the production and deposition on Earth of isotopes with half-lives in the range 10{sup 5}-10{sup 8} yr that might provide signatures of nearby stellar explosions, extending previous analyses of Core-Collapse Supernovae (CCSNe) to include Electron-Capture Supernovae (ECSNe), Super-Asymptotic Giant Branch (SAGB) stars, Thermonuclear/Type Ia Supernovae (TNSNe), and Kilonovae/Neutron Star Mergers (KNe). We revisit previous estimates of the {sup 60}Fe and {sup 26}Al signatures, and extend these estimates to include {sup 244}Pu and {sup 53}Mn. We discuss interpretations of the {sup 60}Fe signals in terrestrial and lunar reservoirs in terms of a nearby stellar ejection ∼2.2 Myr ago, showing that (1) the {sup 60}Fe yield rules out the TNSN and KN interpretations, (2) the {sup 60}Fe signals highly constrain SAGB interpretations but do not completely them rule out, (3) are consistent with a CCSN origin, and (4) are highly compatible with an ECSN interpretation. Future measurements could resolve the radioisotope deposition over time, and we use the Sedov blast wave solution to illustrate possible time-resolved profiles. Measuring such profiles would independently probe the blast properties including distance, and would provide additional constraints for the nature of the explosion.

  6. Study of radioactive isotopes of beryllium, polonium, uranium, and plutonium in the atmosphere

    SciTech Connect

    Lee, S.C.

    1986-01-01

    Radiochemical measurements were carried out for /sup 239.240/Pu in a total of 94 rain and snow samples collected at Fayetteville (36/sup 0/ N, 94/sup 0/W), Arkansas, during the period between May 1983 and November 1985. The concentrations of /sup 7/Be in most of these samples were also measured and these results were compared with previous samples. Average concentrations of cosmic-ray-produced radionuclide /sup 7/Be in rain remained fairly constant year after year. The annual rate of /sup 7/Be deposition at Fayetteville, Arkansas, was calculated from these data to be 5.2 dpm/cm/sup 2//year, which corresponds to a value of 2.8 x 10/sup -2/ atoms/cm/sup 2//second for the /sup 7/Be production rate in the atmosphere. The concentrations of bomb-produced radionuclides such as /sup 89/Sr, /sup 90/Sr and /sup 239.240/Pu in rain have drastically decreased since the last nuclear test explosion was conducted by the government of People's Republic of China in 1980. The concentrations of uranium isotopes and radon daughters in rain, on the other hand, were found to be affected by atmospheric injections of volcanic ashes from the 1980 eruption of Mount St. Helens and the 1982 eruption of El Chichon volcano in Mexico. Moreover, the burnups of the nuclear-powered Soviet satellites have caused marked increases in the levels of /sup 235/U and /sup 234/U in some of the rain samples. A sharp increase in the /sup 210/Po//sup 7/Be ratio in rain samples collected toward the end of 1980 and the beginning of 1981 was attributed to an atmospheric injection of /sup 210/Po from a series of major eruptions of Mount St. Helens.

  7. Radioactive and Stable Paleoatmospheric MethaneIsotopes across the Last Deglaciation and Early Holocene from Taylor Glacier, Antarctica

    NASA Astrophysics Data System (ADS)

    Dyonisius, M.; Petrenko, V. V.; Smith, A.; Hmiel, B.; Vimont, I.; Hua, Q.; Yang, B.; Menking, J. A.; Shackleton, S. A.; Rhodes, R.; Baggenstos, D.; Bauska, T. K.; Bock, M.; Beck, J.; Seth, B.; Harth, C. M.; Beaudette, R.; Schmitt, J.; Brook, E.; Weiss, R. F.; Fischer, H.; Severinghaus, J. P.

    2016-12-01

    Methane (CH4) is an important greenhouse gas with both natural and anthropogenic sources. Understanding how the natural CH4 budget has changed in response to changing climate in the past can provide insights on the sensitivity of the natural CH4 emissions to the current anthropogenic warming. Both radioactive and stable CH4 isotopes (Δ14C-CH4, δ13C-CH4, and δD-CH4) from ice cores in Greenland and Antarctica have been used to constrain the past CH­4 budget. Among the CH4 isotopes, 14CH4 is unique in its ability to unambiguously distinguish between "old" CH4 sources (e.g. marine clathrate, geologic sources, old permafrost) and "modern" CH4 sources (e.g. tropical and boreal wetlands). During the 2013-2014 and 2014-2015 field seasons at Taylor Glacier, Antarctica, we have successfully extracted 12 large volume ice samples across the Last Deglaciation to early Holocene (20ka-8ka BP). All samples have been successfully measured for CH4 mole fraction ([CH4]), Δ14C-14CH4, δ13C-CH4, and δD-CH4. The [CH4], δ13C-CH4, and δD-CH4 measurements in our samples are consistent with existing δ13C-CH4, and δD-CH4 datasets from other deep cores, confirming the integrity of CH4 in Taylor Glacier ice. Preliminary 14CH4 results across the Oldest Dryas - Bølling (OD-BO) CH4 transition suggest that the 150 ppb [CH4] increase during the transition was caused by increased wetland emissions. Early Holocene and Last Glacial Maximum (LGM) 14C results are still undergoing corrections for in-situ cosmogenic 14C based on 14CO measurements in the same samples. We will present the corrected 14CH4 results from these samples and our preliminary interpretations with regard to the strength of old CH4 sources during the LGM and early Holocene.

  8. Detailed analysis of isotopic ratio of radioactive iodine in surface soil around Fukushima Daiichi Nuclear Power Plant

    NASA Astrophysics Data System (ADS)

    Miyake, Yasuto; Matsuzaki, Hiroyuki; Fujiwara, Takeshi; Saito, Takumi; Yamagata, Takeyasu; Honda, Maki

    2013-04-01

    In March 2011, there was an accident at the Fukushima Daiichi Nuclear Power Plant (FDNPP) and a lot of radionuclides were discharged into the environment, resulting from a powerful earthquake and tsunami. Considering the impact on human health, the radiation dosimetry is the most important for Iodine-131 among radionuclides in the initial stage immediately following the release of radionuclides. However, Iodine-131 cannot be detected after several months owing to its short half-life (8 days). Cesium-137 was also leaked out from the FDNPP and this can be detected now. But this did not identically act with Iodine-131 and be suitable for the reconstruction of Iodine-131 distribution at the initial stage. Since Iodine-129 (half-life: 1.57E7 yrs) can be detected in the future and it act chemically identically with Iodine-131, the reconstruction by Iodine-129 analysis is important. For this reconstruction, it is necessary to know the isotopic ratio of radioactive iodine (129I/131I) released from the FDNPP. In this study, the Iodine-129 concentration was measured by accelerator mass spectrometry (AMS) in several surface soil samples collected around the FDNPP for which the Iodine-131level had already been determined. Soil samples were put into a U8 standard vessel after being roughly homogenized and dried. Then, samples were homogenized again more completely and several grams were taken for Iodine-129 measurement. Each sample was combusted in a quartz tube and outgas was trapped in alkali solution. An aliquot was taken from the trap solution for the determination of the Iodine-127 concentration by inductively coupled plasma mass spectrometry (ICP-MS). The iodine carrier was added to the trap solution, from which the iodine fraction was purified by solvent extraction and back extraction. Finally, silver iodide precipitation was obtained by adding silver nitrate solution. After dried, the precipitation was mixed with niobium powder and pressed into a cathode for the target

  9. Carbon isotopic evidence for biodegradation of organic contaminants in the shallow vadose zone of the radioactive waste management complex

    SciTech Connect

    Conrad, Mark E.; DePaolo, Donald J.

    2003-09-04

    Waste material buried in drums in the shallow subsurface at the Radioactive Waste Management Facility (RWMC) of the Idaho National Engineering and Environmental Laboratory (INEEL) contained significant amounts of organic compounds including lubricating oils and chlorinated solvents. CO{sub 2} concentrations in pore gas samples from monitoring wells in the vicinity of the disposal pits are 3 to 5 times higher than the concentrations in nearby background wells. The stable carbon isotope ratios ({delta}{sup 13}C values) of CO{sub 2} from the disposal pits averaged 2.4. less than CO{sub 2} from the background wells, indicating that the elevated CO{sub 2} concentrations around the pits were derived from source materials with {delta}{sup 13}C values in the range of -24{per_thousand} to -29{per_thousand}. These {delta}{sup 13}C values are typical of lubricating oils, but higher than most solvents. The radiocarbon ({sup 14}C) contents of CO{sub 2} across most of the site were significantly elevated above modern concentrations due to reactor blocks buried in a subsurface vault at the site. However, several samples collected from the high-CO{sub 2} zone on the far side of the RWMC from the reactor blocks had very low {sup 14}C contents (less than 0.13 times modern), confirming production from lubricating oils manufactured from fossil hydrocarbons. The magnitude of the CO{sub 2} anomaly observed at the site is consistent with intrinsic biodegradation rates on the order of 0.5 to 3.0 metric tons of carbon per year.

  10. Measurement of natural and {sup 137}Cs radioactivity concentrations at Izmit Bay (Marmara Sea), Turkey

    SciTech Connect

    Öksüz, İ. Güray, R. T. Özkan, N. Yalçin, C.; Ergül, H. A. Aksan, S.

    2016-03-25

    In order to determine the radioactivity level at Izmit Bay Marmara Sea, marine sediment samples were collected from five different locations. The radioactivity concentrations of naturally occurring {sup 238}U, {sup 232}Th and {sup 40}K isotopes and also that of an artificial isotope {sup 137}Cs were measured by using gamma-ray spectroscopy. Preliminary results show that the radioactivity concentrations of {sup 238}U and {sup 232}Th isotopes are lower than the average worldwide values while the radioactivity concentrations of the {sup 40}K are higher than the average worldwide value. A small amount of {sup 137}Cs contamination, which might be caused by the Chernobyl accident, was also detected.

  11. Determination and mapping the spatial distribution of radioactivity of natural spring water in the Eastern Black Sea Region by using artificial neural network method.

    PubMed

    Yeşilkanat, Cafer Mert; Kobya, Yaşar

    2015-09-01

    In this study, radiological distribution of gross alpha, gross beta, (226)Ra, (232)Th, (40)K, and (137)Cs for a total of 40 natural spring water samples obtained from seven cities of the Eastern Black Sea Region was determined by artificial neural network (ANN) method. In the ANN method employed, the backpropagation algorithm, which estimates the backpropagation of the errors and results, was used. In the structure of ANN, five input parameters (latitude, longitude, altitude, major soil groups, and rainfall) were used for natural radionuclides and four input parameters (latitude, longitude, altitude, and rainfall) were used for artificial radionuclides, respectively. In addition, 75 % of the total data were used as the data of training and 25 % of them were used as test data in order to reveal the structure of each radionuclide. It has been seen that the results obtained explain the radiographic structure of the region very well. Spatial interpolation maps covering the whole region were created for each radionuclide including spots not measured by using these results. It has been determined that artificial neural network method can be used for mapping the spatial distribution of radioactivity with this study, which is conducted for the first time for the Black Sea Region.

  12. Downcore sulphur isotope ratios and diatom inferred pH in an artificially acidified Canadian shield lake.

    PubMed

    Dickman, M; Thode, H G; Rao, S; Anderson, R

    1988-01-01

    Three gravity cores were removed from near the deepest point in Lake 223 on 9 June 1984, eight years after the Experimental Lakes Area (ELA) staff began the artificial acidification of the lake with sulphuric acid. The first of these cores was analysed for diatoms and pollen stratigraphy while the second and third were analysed for downcore sulphur isotope ratios (H. Thode) and downcore changes in sulphur reducing bacterial densities (S. Rao). Sediment core chronologies were based on lead-210 and cesium-137 data (R. Anderson) and the Ambrosia pollen rise (M. Dickman). Analysis of the first core to the depth of the Ambrosia pollen rise (9 cm) indicated that diatom inferred pH in Lake 223 at the time of the Ambrosia rise (circa 1890) was 6.8-7.0. At a sediment depth of 3 cm the diatom inferred pH was 6.7. Thereafter diatom inferred pH began a decline culminating in the present day (observed) pH range for 1984 (5.3-5.5). At a sediment depth of 1 cm, an increase in the abundance of two benthic alkalophilic diatoms occurred. The increase in the abundance of these diatoms was ascribed to an increase in hypolimnetic alkalinity following the artificial acidification of Lake 223. This is the first time that lake acidification has been linked to an increase in benthic alkalophilic diatoms associated with hypolimnetic alkalinity production following sulphate reduction. Sulphur in the anaerobic (black) sediment layers (0-1.5 cm) was isotopically light relative to the sulphur in the deeper layers. This was due to sulphur isotope fractionation resulting from the bacterial reduction of sulphate to hydrogen sulphide in the anaerobic portion of the water column. A jet black FeS-rich layer in the uppermost 1.5 cm of the lake's sediments was associated with an increase in the abundance of sulphate reducing bacteria (e.g. Desulfovibrio spp.).

  13. Development of radioactive ion beam production systems for Tokai Radioactive Ion Acceleration Complex--High temperature ion source for short-lived isotopes

    SciTech Connect

    Otokawa, Y.; Osa, A.; Sato, T. K.; Matsuda, M.; Ichikawa, S.; Jeong, S. C.

    2010-02-15

    We have developed a new ion source system in the isotope separator on-line at Japan Atomic Energy Agency, for separation of short-lived isotopes produced by proton-induced fission of {sup 238}U. The ion source system is a forced electron beam induced arc discharge version E type ion source with a target container. We successfully operated this system at 2000 deg. C as a result of reductions in volume of the ion source and the target container, introduction of heating method by electron bombardment, and improvement to the heat shield. This new ion source system was tested using {sup 238}U of 640 mg/cm{sup 2} with a proton primary beam of 30 MeV, 350 nA. Release times were measured for Kr, In, and Xe. The values of release times are 2.6 s for Kr, 1.8 s for In, and 4.6 s for Xe. In this work, the ion source system enabled us to mass-separate short-lived isotopes such as {sup 93}Kr(T{sub 1/2}=1.286 s), {sup 129}In(T{sub 1/2}=0.61 s), and {sup 141}Xe(T{sub 1/2}=1.73 s) with intensity of 10{sup 3} ions/s.

  14. Measurements of CO2 Carbon Stable Isotopes at Artificial and Natural Analog Sites

    NASA Astrophysics Data System (ADS)

    Humphries, S. D.; Clegg, S. M.; Rahn, T.; Fessenden, J. E.; Dobeck, L.; Spangler, L.; McLing, T. L.

    2010-12-01

    Carbon storage in geologic formations is one method to prevent carbon dioxide (CO2), produced by fossil fuel combustion, from entering the Earth's atmosphere. The monitoring, verification and accounting (MVA) of geologically sequestered CO2 is critical to the operation of a geologic storage site. Surface MVA techniques need to identify seepage from the sequestration reservoir at or below ambient CO2 concentrations. The CO2 carbon stable isotope ratio of is a sensitive diagnostic signature that can distinguish between anthropogenic and natural sources of CO2. Frequency Modulated spectroscopy (FMS) is an ultra-sensitive version of absorption spectroscopy that is capable of detecting the CO2 carbon stable isotope ratios. The technique involves phase modulation of the laser such that two side bands, spaced wider than the absorption feature of interest (in this case +/-2 GHz) are created. The signal is mixed with the local oscillator yielding a signal proportional to the species concentration. This FMS signature is recorded at multiple wavelengths to obtain the CO2 carbon isotope ratio.Two instruments using the FMS technique have been built and tested at LANL. One instrument draws ambient air into a multi-pass cell for a measurement, point source measurements. The other instrument uses an open-air path, tested up to 160 m (round trip), to measure the CO2 carbon isotopic ratio along the beam path, column average measurements. In this paper, results from multiple field deployments of one or both of the instruments will be presented. The Zero Emissions Research & Technology (ZERT) group at Montana State University established a field test site where controlled amounts of CO2 are released to test the performance of CO2 detection instruments and measurement techniques. The field site allows a controlled flow rate of CO2 to be released into the near surface through a 100 m long horizontal pipe. In July of 2009, a release was conducted, with a uniform flow rate of 0.2 tons per

  15. Isotopic re-equilibration of fluid inclusions in natural speleothem by artificial heating

    NASA Astrophysics Data System (ADS)

    Uemura, Ryu; Kina, Yudai

    2017-04-01

    Isotopic compositions of inclusion water in speleothems are promising new climatic proxies. Oxygen isotope ratio of water (δ18O) may provide direct estimate for past temperature changes. Several studies, however, used hydrogen isotope ratio of water (δD) because the δ18O may be affected by re-equilibration between water and host calcite. Thus, precise knowledge about magnitude and reaction rate of the re-equilibration has a fundamental importance for paleoclimate studies using speleothems. To evaluate the re-equilibration effect, we measured isotope composition of fluid inclusions in natural stalagmites, which had been heated in laboratory before isotope measurement. Several (3-5) subsamples were cut from the same depth of stalagmites. Then, each sub-sample was heated at different interval (0 - 80 hours) under continuous evacuation using a turbomolecular pump. The experiments were conducted under three different temperatures (25, 70, and 105˚ C). The δ18O and δD values of fluid inclusions in a sub-sample was measured using a semi-automated system, which was modified based on cavity ring-down spectroscopy technique (Uemura et al., 2016). Under the 105˚ C hating, the inclusion δ18O value of a layer shows a small increase from the initial to ca.30 hours heating, and then after that it appears to stay flat. This preliminary result suggests that a limited amount of calcite reacts with inclusion water, and ca. 5% of fluid inclusion water may be re-equilibrated with surrounding host calcite at the 105˚ C. The magnitude of re-equilibration effect is not significant for estimating glacial-interglacial temperature changes but measurable. On the other hand, the δ18O value shows no trend under the room temperature experiment. The δD value shows no trend at any experimental conditions, suggesting that loss of inclusion water during long-time evacuation does not cause the δ18O enrichment. Uemura, R. et al. (2016) Precise oxygen and hydrogen isotopic determination of

  16. Radioactive Cesium Isotope Ratios as a Tool for determining Dispersal and Re-dispersal Mechanisms Downwind from the Nevada Nuclear Security Site

    SciTech Connect

    Darin C. Snyder; James E. Delmore; Troy J. Tranter; Nick R. Mann; Michael L. Abbott; John E. Olson

    2012-08-01

    Fractionation of the two longer lived radioactive cesium isotopes (135 and 137) produced by above ground nuclear tests have been measured and used to clarify the dispersal mechanisms of cesium deposited in the area between the Nevada Nuclear Security Site (NNSS) and Lake Mead in the southwestern United States. Fractionation of these isotopes is due to the 135 decay chain requiring several days to completely decay to Cs and the 137 decay chain less than one hour. Since the Cs precursors are gases, iodine and xenon, the 135Cs plume was deposited farther downwind than the 137Cs plume. Samples were obtained from the Las Vegas arm of Lake Mead, separated into segments, gamma counted to identify layers of activity and analyzed for 135Cs/137Cs ratios. The layers proved to have nearly identical highly fractionated isotope ratios. This information is consistent with a model where the cesium was initially deposited onto the land area draining into Lake Mead and the composite from all the above ground shots subsequently washed onto the Lake by high intensity rain and windstorms producing a layering of Cs activity where each layer is a portion of the composite.

  17. Radioactive cesium isotope ratios as a tool for determining dispersal and re-dispersal mechanisms downwind from the Nevada Nuclear Security Site.

    PubMed

    Snyder, Darin C; Delmore, James E; Tranter, Troy; Mann, Nick R; Abbott, Michael L; Olson, John E

    2012-08-01

    Fractionation of the two longer-lived radioactive cesium isotopes ((135)Cs and (137)Cs) produced by above ground nuclear tests have been measured and used to clarify the dispersal mechanisms of cesium deposited in the area between the Nevada Nuclear Security Site and Lake Mead in the southwestern United States. Fractionation of these isotopes is due to the 135-decay chain requiring several days to completely decay to (135)Cs, and the 137-decay chain less than one hour decay to (137)Cs. Since the Cs precursors are gases, iodine and xenon, the (135)Cs plume was deposited farther downwind than the (137)Cs plume. Sediment core samples were obtained from the Las Vegas arm of Lake Mead, sub-sampled and analyzed for (135)Cs/(137)Cs ratios by thermal ionization mass spectrometry. The layers proved to have nearly identical highly fractionated isotope ratios. This information is consistent with a model where the cesium was initially deposited onto the land area draining into Lake Mead and the composite from all of the above ground shots subsequently washed onto Lake Mead by high intensity rain and wind storms producing a layering of Cs activity, where each layer is a portion of the composite.

  18. A kinematic model to estimate the effective dose of radioactive isotopes in the human body for radiological protection

    NASA Astrophysics Data System (ADS)

    Sasaki, S.; Yamada, T.

    2013-12-01

    The great earthquake attacked the north-east area in Japan in March 11, 2011. The system of electrical facilities to control Fukushima Daiichi nuclear power station was completely destroyed by the following tsunamis. From the damaged reactor containment vessels, an amount of radioactive substances had leaked and been diffused in the vicinity of this station. Radiological internal exposure becomes a serious social issue both in Japan and all over the world. The present study provides an easily understandable, kinematic-based model to estimate the effective dose of radioactive substances in a human body by simplified the complicated mechanism of metabolism. International Commission on Radiological Protection (ICRP) has developed an exact model, which is well-known as a standard method to calculate the effective dose for radiological protection. However, owing to that the above method accord too much with the actual mechanism of metabolism in human bodies, it becomes rather difficult for non-professional people of radiology to gasp the whole images of the movement and the influences of radioactive substances in a human body. Therefore, in the present paper we propose a newly-derived and easily-understandable model to estimate the effective dose. The present method is very similar with the traditional and conventional hydrological tank model. Ingestion flux of radioactive substances corresponds to rain intensity and the storage of radioactive substances to the water storage in a basin in runoff analysis. The key of this method is to estimate the energy radiated from the radioactive nuclear disintegration of an atom by using classical theory of E. Fermi of beta decay and special relativity for various kinds of radioactive atoms. The parameters used in this study are only physical half-time and biological half-time, and there are no intentional and operational parameters of coefficients to adjust our theoretical runoff to observation of ICRP. Figure.1 compares time

  19. Radioactivity: A Natural Phenomenon.

    ERIC Educational Resources Information Center

    Ronneau, C.

    1990-01-01

    Discussed is misinformation people have on the subject of radiation. The importance of comparing artificial source levels of radiation to natural levels is emphasized. Measurements of radioactivity, its consequences, and comparisons between the risks induced by radiation in the environment and from artificial sources are included. (KR)

  20. Radioactivity: A Natural Phenomenon.

    ERIC Educational Resources Information Center

    Ronneau, C.

    1990-01-01

    Discussed is misinformation people have on the subject of radiation. The importance of comparing artificial source levels of radiation to natural levels is emphasized. Measurements of radioactivity, its consequences, and comparisons between the risks induced by radiation in the environment and from artificial sources are included. (KR)

  1. Isotope tracer approaches for characterizing artificial recharge and demonstrating regulatory compliance

    SciTech Connect

    Davisson, M.L.; Hudson, G.B.; Moran, J.E.; Neimeyer, S.; Herndon, R., LLNL

    1998-05-01

    Potable reuse of groundwater from wastewater origins requires new methods to quantify proposed regulatory criteria such as subsurface residence times, dilution, and water quality transitions. Isotope tracers oxygen-18 ({sup 18}O), tritium ({sup 3}H), dissolved noble gases, and radiocarbon ({sup 14}C) have been used together in Orange County to age-date groundwater, quantify mixing, and characterize changes in total organic carbon (TOC). Simultaneous measurements of {sup 3}H and helium-3 ({sup 3}He) are used to determine groundwater ages between 1 and 40 years with uncertainties of plus/minus one year. These ages map preferred groundwater flowpaths and identify groundwater ages of less than or equal to 1 year. Wells recharged from the Anaheim Lake spreading basin were used to monitor arrival times and dilution of 6000 acre-ft of {sup 18}O-distinct Colorado River (COR) water introduced during a controlled recharge experiment. In addition, isotopically enriched Xe was introduced into the basin to quantify COR dilution of greater than 90%. The COR arrived at 7 wells between 30 and 200 days after recharge commenced. The COR was diluted up to 90% at distances and depths less than 1000 feet from the lake. Results suggest that dilution of 50% is obtained within 6 months from time or recharge. {sup 14}C measured in TOC of Anaheim Lake bottom water was 3 pmc higher than the DOC. The same water collected one month later in a nearby monitoring well, as confirmed by {sup 18}O, showed a 50% reduction in TOC concentration, and a 7 pmc decrease in {sup 14}C relative to the surface water. This result suggests that older carbon components increase in TOC after recharge.

  2. WWW Table of Radioactive Isotopes (TORI or ToI) from the Isotopes Project: Lawrence Berkeley National Laboratory - Lund University Collaboration

    DOE Data Explorer

    Firestone, R. B. [LBNL; Ekstrom, L. P. [LUNDS Universitet; Chu, S. Y.F. [LBNL

    The handbook titled "Table of Isotopes" has long been a standard source of information for nuclear structure and decay data. This web page provides online access to the "Table of Isotopes" data. It provides specialized interfaces to search, including: 1) Radiation search - search for by energy range and/or parent properties; 2) Nuclide search - search for nuclides by A, Z, N, and/or half-life range; 3) Atomic data - search for X-rays and Auger electrons; 4) Periodic table interface to the nuclides; 5) Summary drawings for A=1-277 (PDF). This page also provides access to various other resources, including the WWW Table of Nuclear Structure where the user can interactively search adopted nuclear level and gamma-ray properties or display tables, level scheme ladder diagrams and nuclear charts.

  3. Malformation of true bug (Heteroptera): a phenotype field study on the possible influence of artificial low-level radioactivity.

    PubMed

    Hesse-Honegger, Cornelia; Wallimann, Peter

    2008-04-01

    The results of extensive field studies on the malformation of Western European true bugs (Heteroptera) are reviewed. More than 16,000 individuals were collected over two decades, and subjected to detailed visual inspection. Various types of disturbances were found and illustrated in detail. Depending on country, region, as well as local influences, severe disturbances and high degrees of malformation were noticed, especially in the sphere of nuclear-power installations in Switzerland (Aargau), France (La Hague), and Germany (Gundremmingen). Malformation reached values as high as 22 and 30% for morphological (MD) and total disturbance (TD), respectively. This is far above the values expected for natural populations (ca. 1%) or those determined for true bugs living in biotopes considered as relatively 'intact' (1-3%). A detailed chi-square test of the malformation data obtained for 650 true bugs from 13 collection sites near the nuclear-reprocessing plant La Hague showed a highly significant correlation (p=0.003) between malformation and wind exposure/local topography. Similar observations were made for other study sites. Currently, our data are best rationalized by assuming a direct influence between the release of anthropogenic radionuclides such as tritium ((3)H), carbon-14 ((14)C), or iodine-131 ((131)I), constantly emitted by nuclear-power and nuclear-reprocessing plants, as well as by Chernobyl and bomb-testing fallout, which is rich in caesium-137 ((137)Cs) and other long-lived noxious isotopes that have entered the food chain. The present work supports the growing evidence that low-level radiation, especially in the form of randomly scattered 'hot' alpha- and beta-particles, mainly transported via aerosols, puts a heavy burden on the biosphere in general, and on true bugs in particular. These insects could, thus, serve as sensitive 'bio-indicators' for future studies.

  4. Atmospheric plume progression as a function of time and distance from the release point for radioactive isotopes

    SciTech Connect

    Eslinger, Paul W.; Bowyer, Ted W.; Cameron, Ian M.; Hayes, James C.; Miley, Harry S.

    2015-10-01

    The International Monitoring System contains up to 80 stations around the world that have aerosol and xenon monitoring systems designed to detect releases of radioactive materials to the atmosphere from nuclear tests. A rule of thumb description of plume concentration and duration versus time and distance from the release point is useful when designing and deploying new sample collection systems. This paper uses plume development from atmospheric transport modeling to provide a power-law rule describing atmospheric dilution factors as a function of distance from the release point.

  5. Radioactive Iodine (I-131) Therapy for Hyperthyroidism

    MedlinePlus

    ... Physician Resources Professions Site Index A-Z Radioactive Iodine (I-131) Therapy Radioiodine therapy is a nuclear ... thyroid cancer. When a small dose of radioactive iodine I-131 (an isotope of iodine that emits ...

  6. Nuclear structure from radioactive decay. Annual progress report

    SciTech Connect

    Wood, J.L.

    1991-09-30

    This report discusses nuclear structure from radioactive decay of the following: Neutron-Deficient Iridium Isotopes; Neutron-Deficient Platinum Isotopes; Neutron-Deficient Gold Isotopes; Neutron-Deficient Mercury Isotopes; Neutron-Deficient Thallium Isotopes; Neutron-Deficient Lead Isotopes; Neutron-Deficient Samarium Isotopes; Neutron-Deficient Promethium Isotopes; Neutron-Deficient Neodymium Isotopes; and Neutron-Deficient Praseodymium Isotopes. Also discussed are Nuclear Systematics and Models.

  7. Birds as objects in bioindication of radioactive pollution.

    PubMed

    Krivolutski, D A; Lebedeva, N V; Shuktomova, I I

    1999-01-01

    This article is a review the recent results of research in the accumulation of natural and artificial radionuclides in birds from Russia (Adigea, Krasnodar, Rostov, Astrahan and Moscow regions, Novaya Zemlya isles), Ukraine, Vietnam, Poland, Ethiophia and Mongolia after global precipitation and local pollution, such as in the East-Urals radioactive region and radioactive zones after the Chernobyl accident. Resident birds reflect local level of radionuclide contamination. The 90Sr concentration in the food of the Pied Flycatcher had a tendency to increase in dependent of age. The Common Jay and the Mallard were the most contaminated with 137Cs in the Bryansk region. The total content of various radio-isotopes of plutonium in bird bones from Southwest Russia were hundred and thousand times more, than in Mongolia. Activity levels in specimens from Ethiopia bear record to Ethiopia can notbe a "pure" control site in radioecological research and radioactive background since it does not significantly differ from Turkmenia and Mongolia.

  8. Strontium Isotopes in Pore Water as an Indicator of Water Flux at the Proposed High-Level Radioactive Waste Repository, Yucca Mountain, Nevada

    SciTech Connect

    B. Marshall; K. Futa

    2004-02-19

    The proposed high-level radioactive waste repository at Yucca Mountain, Nevada, would be constructed in the high-silica rhyolite (Tptp) member of the Miocene-age Topopah Spring Tuff, a mostly welded ash-flow tuff in the {approx}500-m-thick unsaturated zone. Strontium isotope compositions have been measured in pore water centrifuged from preserved core samples and in leachates of pore-water salts from dried core samples, both from boreholes in the Tptp. Strontium isotope ratios ({sup 87}Sr/{sup 86}Sr) vary systematically with depth in the surface-based boreholes. Ratios in pore water near the surface (0.7114 to 0.7124) reflect the range of ratios in soil carbonate (0.7112 to 0.7125) collected near the boreholes, but ratios in the Tptp (0.7122 to 0.7127) at depths of 150 to 370 m have a narrower range and are more radiogenic due to interaction with the volcanic rocks (primarily non-welded tuffs) above the Tptp. An advection-reaction model relates the rate of strontium dissolution from the rocks with flow velocity. The model results agree with the low transport velocity ({approx}2 cm per year) calculated from carbon-14 data by I.C. Yang (2002, App. Geochem., v. 17, no. 6, p. 807-817). Strontium isotope ratios in pore water from Tptp samples from horizontal boreholes collared in tunnels at the proposed repository horizon have a similar range (0.7121 to 0.7127), also indicating a low transport velocity. Strontium isotope compositions of pore water below the proposed repository in core samples from boreholes drilled vertically downward from tunnel floors are more varied, ranging from 0.7112 to 0.7127. The lower ratios (<0.7121) indicate that some of the pore water in these boreholes was replaced by tunnel construction water, which had an {sup 87}Sr/{sup 86}Sr of 0.7115. Ratios lower than 0.7115 likely reflect interaction of construction water with concrete in the tunnel inverts, which had an {sup 87}Sr/{sup 86}Sr < 0.709. These low Sr ratios indicate penetration of

  9. Hydrological investigation of a multi-stratified pit lake using radioactive and stable isotopes combined with hydrometric monitoring

    NASA Astrophysics Data System (ADS)

    Sánchez-España, Javier; Diez Ercilla, Marta; Pérez Cerdán, Fernando; Yusta, Iñaki; Boyce, Adrian J.

    2014-04-01

    The internal configuration and hydrological dynamics of meromictic pit lakes is often complex and needs to be studied by different tools including stable and radiogenic isotopes. This study combines a multi-isotopic approach (3Hw, δ2Hw, δ18Ow, δ34SSO4) with meteorological, hydrological and hydrochemical monitoring to deduce the flooding history and hydrological dynamics of a meromictic and deeply stratified pit lake (Cueva de la Mora mine, SW Spain). The mine system is complex and includes horizontal galleries, shafts and large rooms physically connected to the mine pit. Specific conductance and temperature profiles obtained in the pit lake draw a physical structure with four monimolimnetic sub-layers of increasing density with depth. This characteristic stratification with m-scale layers separated by sharp transitional zones is rather unusual in other pit lakes and in most natural lakes. Tritium abundance in the different layers indicates that the deep lake water entered the pit basin between 1971 and 1972 which is coincident with the dates of mine closure. The oxygen and deuterium isotope composition of the different layers describes a marked and stable stratification, with an increasing evaporative influence towards the lake surface and a minimal influence of groundwater flow on the structure and composition of the monimolimnion. This study reveals that the initial stages of flooding (via influx of metal- and sulfate-loaded mine drainage from underlying galleries at different depths) may be essential to imprint a layered physical structure to pit lakes which would be very difficult to explain merely by physical processes. After reaching its present water level and morphology, the monimolimnion of this pit lake seems to have remained essentially isolated and chemically unmodified during decades.

  10. Atmospheric plume progression as a function of time and distance from the release point for radioactive isotopes.

    PubMed

    Eslinger, Paul W; Bowyer, Ted W; Cameron, Ian M; Hayes, James C; Miley, Harry S

    2015-10-01

    The radionuclide network of the International Monitoring System comprises up to 80 stations around the world that have aerosol and xenon monitoring systems designed to detect releases of radioactive materials to the atmosphere from nuclear explosions. A rule of thumb description of plume concentration and duration versus time and distance from the release point is useful when designing and deploying new sample collection systems. This paper uses plume development from atmospheric transport modeling to provide a power-law rule describing atmospheric dilution factors as a function of distance from the release point. Consider the plume center-line concentration seen by a ground-level sampler as a function of time based on a short-duration ground-level release of a nondepositing radioactive tracer. The concentration C (Bq m(-3)) near the ground varies with distance from the source with the relationship C=R×A(D,C) ×e (-λ(-1.552+0.0405×D)) × 5.37×10(-8) × D(-2.35) where R is the release magnitude (Bq), D is the separation distance (km) from the ground level release to the measurement location, λ is the decay constant (h(-1)) for the radionuclide of interest and AD,C is an attenuation factor that depends on the length of the sample collection period. This relationship is based on the median concentration for 10 release locations with different geographic characteristics and 365 days of releases at each location, and it has an R(2) of 0.99 for 32 distances from 100 to 3000 km. In addition, 90 percent of the modeled plumes fall within approximately one order of magnitude of this curve for all distances. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Development of Innovative Radioactive Isotope Production Techniques at the Pennsylvania State University Radiation Science and Engineering Center

    SciTech Connect

    Johnsen, Amanda M.; Heidrich, Brenden; Durrant, Chad; Bascom, Andrew; Unlu, Kenan

    2013-08-15

    The Penn State Breazeale Nuclear Reactor (PSBR) at the Radiation Science and Engineering Center (RSEC) has produced radioisotopes for research and commercial purposes since 1956. With the rebirth of the radiochemistry education and research program at the RSEC, the Center stands poised to produce a variety of radioisotopes for research and industrial work that is in line with the mission of the DOE Office of Science, Office of Nuclear Physics, Isotope Development and Production Research and Application Program. The RSEC received funding from the Office of Science in 2010 to improve production techniques and develop new capabilities. Under this program, we improved our existing techniques to provide four radioisotopes (Mn-56, Br-82, Na-24, and Ar-41) to researchers and industry in a safe and efficient manner. The RSEC is also working to develop new innovative techniques to provide isotopes in short supply to researchers and others in the scientific community, specifically Cu-64 and Cu-67. Improving our existing radioisotopes production techniques and investigating new and innovative methods are two of the main initiatives of the radiochemistry research program at the RSEC.

  12. Dynamic radioactive particle source

    DOEpatents

    Moore, Murray E; Gauss, Adam Benjamin; Justus, Alan Lawrence

    2012-06-26

    A method and apparatus for providing a timed, synchronized dynamic alpha or beta particle source for testing the response of continuous air monitors (CAMs) for airborne alpha or beta emitters is provided. The method includes providing a radioactive source; placing the radioactive source inside the detection volume of a CAM; and introducing an alpha or beta-emitting isotope while the CAM is in a normal functioning mode.

  13. Search for extinct natural radioactivity of Pb205 via thallium-isotope anomalies in chondrites and lunar soil.

    NASA Technical Reports Server (NTRS)

    Huey, J. M.; Kohman, T. P.

    1972-01-01

    Thallium and Pb204 contents were determined by stable-isotope-dilution analysis in 16 chondrites, one achondrite, and Apollo 11 and 12 lunar fines. Meteoritic thallium contents vary over a large range, 0.02 to 100 ppb, corresponding to the fact that thallium is a highly fractionated volatile element. Lunar thallium contents are less than 5 ppb. The Tl205/Tl203 ratio was determined in most of the samples, with precision ranging from 0.03% to several percent depending mainly on the amount of thallium present. No variations from the terrestrial ratio were observed. The chondritic isochron slope for Pb205 (13.8-m.y. half-life) is less than or equal to 0.00009 (99% confidence level), corresponding to an interval of at least 60 m.y. and possibly exceeding 120 m.y. between the termination of s-process nucleosynthesis and the lead-thallium fractionations.

  14. [The distribution of artificial radionuclides in the biomass of macrophytes of the Yenisei River].

    PubMed

    Zotina, T A

    2009-01-01

    The Yenisei River is contaminated with artificial radionuclides due to the operation of the Mining-and-Chemical Combine (MCC), Rosatom, producing weapon grade plutonium for several decades. Artificial radionuclides including activation isotopes and transuranics, are detected in the biomass of submerged aquatic plants of the river. We investigated the distribution of artificial radionuclides in the biomass of macrophytes from radioactively contaminated part of the Yenisei River with chemical fractionation techniques. Artificial radionuclides were detected in extracellular and intracellular compartments of the macrophytes. The distribution of radionuclides among the biomass fractions differed essentially. 54Mn was preferably in mobile, exchangeable form compared to other isotopes. Essential portion of 137Cs was in non exchangeable form. Significant activity of artificial radionuclides was detected in the particles of suspended matter of the river, attached to the plant surfaces. Radioactive isotopes were distributed among biomass fractions similar to stable isotopes. The distribution of potassium and 137Cs differed essentially. On the basis of the results obtained the assumptions on the further migration of radionuclides accumulated by aquatic macrophytes in the Yenisei River have been done.

  15. Electroweak Decay Studies of Highly Charged Radioactive Ions with TITAN at TRIUMF

    NASA Astrophysics Data System (ADS)

    Leach, Kyle; Dillmann, Iris; Klawitter, Renee; Leistenschneider, Erich; Lennarz, Annika; Brunner, Thomas; Frekers, Dieter; Andreoiu, Corina; Kwiatkowski, Anna; Dilling, Jens

    2017-03-01

    Several modes of electroweak radioactive decay require an interaction between the nucleus and bound electrons within the constituent atom. Thus, the probabilities of the respective decays are not only influenced by the structure of the initial and final states in the nucleus, but can also depend strongly on the atomic charge. Conditions suitable for the partial or complete ionization of these rare isotopes occur naturally in hot, dense astrophysical environments, but can also be artificially generated in the laboratory to selectively block certain radioactive decay modes. Direct experimental studies on such scenarios are extremely difficult due to the laboratory conditions required to generate and store radioactive ions at high charge states. A new electron-beam ion trap (EBIT) decay setup with the TITAN experiment at TRIUMF has successfully demonstrated such techniques for performing spectroscopy on the radioactive decay of highly charged ions.

  16. Radioactive Decay

    EPA Pesticide Factsheets

    Radioactive decay is the emission of energy in the form of ionizing radiation. Example decay chains illustrate how radioactive atoms can go through many transformations as they become stable and no longer radioactive.

  17. The artificial and natural isotopes distribution in sedge (Carex L.) biomass from the Yenisei River flood-plain: Adaptation of the sequential elution technique.

    PubMed

    Kropacheva, Marya; Melgunov, Mikhail; Makarova, Irina

    2017-02-01

    The study of migration pathways of artificial isotopes in the flood-plain biogeocoenoses, impacted by the nuclear fuel cycle plants, requires determination of isotope speciations in the biomass of higher terrestrial plants. The optimal method for their determination is the sequential elution technique (SET). The technique was originally developed to study atmospheric pollution by metals and has been applied to lichens, terrestrial and aquatic bryophytes. Due to morphological and physiological differences, it was necessary to adapt SET for new objects: coastal macrophytes growing on the banks of the Yenisei flood-plain islands in the near impact zone of Krasnoyarsk Mining and Chemical Combine (KMCC). In the first version of SET, 20 mM Na2EDTA was used as a reagent at the first stage; in the second version of SET, it was 1 M CH3COONH4. Four fractions were extracted. Fraction I included elements from the intercellular space and those connected with the outer side of the cell wall. Fraction II contained intracellular elements; fraction III contained elements firmly bound in the cell wall and associated structures; fraction IV contained insoluble residue. Adaptation of SET has shown that the first stage should be performed immediately after sampling. Separation of fractions III and IV can be neglected, since the output of isotopes into the IV fraction is at the level of error detection. The most adequate version of SET for terrestrial vascular plants is the version using 20 mM Na2EDTA at the first stage. Isotope (90)Sr is most sensitive to the technique changes. Its distribution depends strongly on both the extractant used at stage 1 and duration of the first stage. Distribution of artificial radionuclides in the biomass of terrestrial vascular plants can vary from year to year and depends significantly on the age of the plant.

  18. TABLE OF RADIOACTIVE ELEMENTS.

    SciTech Connect

    HOLDEN,N.E.

    2001-06-29

    For those chemical elements which have no stable nuclides with a terrestrial isotopic composition, the data on radioactive half-lives and relative atomic masses for the nuclides of interest and importance have been evaluated and the recommended values and uncertainties are listed.

  19. TABLE OF RADIOACTIVE ELEMENTS.

    SciTech Connect

    HOLDEN,N.E.

    2001-06-29

    For those chemical elements which have no stable nuclides with a terrestrial isotopic composition, the data on radioactive half-lives and relative atomic masses for the nuclides of interest and importance have been evaluated and the recommended values and uncertainties are listed.

  20. Tracing the source of sedimentary organic carbon in the Loess Plateau of China: An integrated elemental ratio, stable carbon signatures, and radioactive isotopes approach.

    PubMed

    Liu, Chun; Dong, Yuting; Li, Zhongwu; Chang, Xiaofeng; Nie, Xiaodong; Liu, Lin; Xiao, Haibing; Bashir, Hassan

    2017-02-01

    Soil erosion, which will induce the redistribution of soil and associated soil organic carbon (SOC) on the Earth's surface, is of critically importance for biogeochemical cycling of essential elements and terrestrial carbon sequestration. Despite the importance of soil erosion, surprisingly few studies have evaluated the sources of eroded carbon (C). This study used natural abundance levels of the stable isotope signature ((13)C) and radioactive isotopes ((137)Cs and (210)Pbex), along with elements ratio (C/N) based on a two end member mixing model to qualitatively and quantitatively identify the sources of sedimentary OC retained by check dam in the Qiaozigou small watershed in the Loess Plateau, China. Sediment profiles (0-200 cm) captured at natural depositional area of the basin was compared to possible source materials, which included: superficial Loess mineral soils (0-20 cm) from three land use types [i.e., grassland (Medicago sativa), forestland (Robinia pseudoacacia.), shrubland (Prunus sibirica), and gully land (Loess parent material.)]. The results demonstrated that SOC in sediments showed significantly negative correlation with pH (P < 0.01), and positive correlation with soil water content (SWC) (P < 0.05). The sedimentary OC was not derived from grasslands or gullies. Forestland and shrubland were two main sources of eroded organic carbon within the surface sediment (0-60 cm deep), except for that in the 20-40 cm soil layer. Radionuclides analyses also implied that the surface sediments retained by check-dams mainly originated from soils of forestland and shrubland. Results of the two end-member mixing model demonstrated that more than 50% SOC (mean probability estimate (MPE) 50.13% via (13)C and 60.53% via C/N) in surface sediment (0-20 cm deep) derived from forestland, whereas subsurface sedimentary SOC (20-200 cm) mainly resulted from shrubland (MPE > 50%). Although uncertainties on the sources of SOC in deep soils exist, the soil

  1. Radium, Thorium and Radioactive Lead Isotopes in Groundwaters: Application to the in Situ Determination of Adsorption-Desorption Rate Constants and Retardation Factors

    NASA Astrophysics Data System (ADS)

    Krishnaswami, S.; Graustein, William C.; Turekian, Karl K.; Dowd, John F.

    1982-12-01

    Five groundwater samples taken from different Hydrogeologie settings in Connecticut were analyzed for major cation chemistry and the concentration of U and Th decay series nuclides 238U, 234Th, 226Ra, 222Rn, 210Pb, 210Po, 232Th, 228Ra, 228Th, and 224Ra. The concentration of 222Rn in the waters ranged between 103 and 104 dpm l-1 and was three to four orders of magnitude greater than that of the short-lived alpha daughters 224Ra, 228Ra, and 234Th, even though the rates of supply of these four nuclides to solution are expected to be similar. We infer that sorption removes radium and thorium from these groundwaters on a time scale of 3 minutes or less. The (224Ra/228Ra) and (234Th/228Th) activity ratios in these waters indicate that desorption of these nuclides occurs on a time scale of a week or less and that equilibrium between solution and surface phases is established. In situ retardation factors for radium, thorium, and lead may therefore be calculated directly from the isotopic data; values range from 4,500 to 200,000. Neither sorption time scales nor retardation factors are strongly dependent on the nuclide or on hydrogeology of the aquifer. Since our study includes nuclides with diverse chemical properties, we suggest that other uncomplexed heavy metals and transuranic elements will also behave in a manner similar to those measured here. The approach presented here should therefore find application in developing site-specific models of the transport of radioactive or stable elemental waste through water-saturated media.

  2. Predicting equilibrium vapour pressure isotope effects by using artificial neural networks or multi-linear regression - A quantitative structure property relationship approach.

    PubMed

    Parinet, Julien; Julien, Maxime; Nun, Pierrick; Robins, Richard J; Remaud, Gerald; Höhener, Patrick

    2015-09-01

    We aim at predicting the effect of structure and isotopic substitutions on the equilibrium vapour pressure isotope effect of various organic compounds (alcohols, acids, alkanes, alkenes and aromatics) at intermediate temperatures. We attempt to explore quantitative structure property relationships by using artificial neural networks (ANN); the multi-layer perceptron (MLP) and compare the performances of it with multi-linear regression (MLR). These approaches are based on the relationship between the molecular structure (organic chain, polar functions, type of functions, type of isotope involved) of the organic compounds, and their equilibrium vapour pressure. A data set of 130 equilibrium vapour pressure isotope effects was used: 112 were used in the training set and the remaining 18 were used for the test/validation dataset. Two sets of descriptors were tested, a set with all the descriptors: number of(12)C, (13)C, (16)O, (18)O, (1)H, (2)H, OH functions, OD functions, CO functions, Connolly Solvent Accessible Surface Area (CSA) and temperature and a reduced set of descriptors. The dependent variable (the output) is the natural logarithm of the ratios of vapour pressures (ln R), expressed as light/heavy as in classical literature. Since the database is rather small, the leave-one-out procedure was used to validate both models. Considering higher determination coefficients and lower error values, it is concluded that the multi-layer perceptron provided better results compared to multi-linear regression. The stepwise regression procedure is a useful tool to reduce the number of descriptors. To our knowledge, a Quantitative Structure Property Relationship (QSPR) approach for isotopic studies is novel.

  3. Radioactivity and the Biology Teacher

    ERIC Educational Resources Information Center

    Hornsey, D. J.

    1974-01-01

    Discusses minimum necessary nuclear fundamentals of radioactive isotopes such as levels of activity, specific activity and the use of carrier materials. Corrections that need to be taken into account in using an isotope to obtain a valid result are also described and statistics for a valid result are included. (BR)

  4. Radioactivity and the Biology Teacher

    ERIC Educational Resources Information Center

    Hornsey, D. J.

    1974-01-01

    Discusses minimum necessary nuclear fundamentals of radioactive isotopes such as levels of activity, specific activity and the use of carrier materials. Corrections that need to be taken into account in using an isotope to obtain a valid result are also described and statistics for a valid result are included. (BR)

  5. Understanding radioactive waste

    SciTech Connect

    Murray, R.L.

    1981-12-01

    This document contains information on all aspects of radioactive wastes. Facts are presented about radioactive wastes simply, clearly and in an unbiased manner which makes the information readily accessible to the interested public. The contents are as follows: questions and concerns about wastes; atoms and chemistry; radioactivity; kinds of radiation; biological effects of radiation; radiation standards and protection; fission and fission products; the Manhattan Project; defense and development; uses of isotopes and radiation; classification of wastes; spent fuels from nuclear reactors; storage of spent fuel; reprocessing, recycling, and resources; uranium mill tailings; low-level wastes; transportation; methods of handling high-level nuclear wastes; project salt vault; multiple barrier approach; research on waste isolation; legal requiremnts; the national waste management program; societal aspects of radioactive wastes; perspectives; glossary; appendix A (scientific American articles); appendix B (reference material on wastes). (ATT)

  6. RADIOACTIVE CHEMICAL ELEMENTS IN THE ATOMIC TABLE.

    SciTech Connect

    HOLDEN, N.E.

    2005-08-13

    In the 1949 Report of the Atomic Weights Commission, a series of new elements were added to the Atomic Weights Table. Since these elements had been produced in the laboratory and were not discovered in nature, the atomic weight value of these artificial products would depend upon the production method. Since atomic weight is a property of an element as it occurs in nature, it would be incorrect to assign an atomic weight value to that element. As a result of that discussion, the Commission decided to provide only the mass number of the most stable (longest-lived) known isotope as the number to be associated with these entries in the Atomic Weights Table. As a function of time, the mass number associated with various elements has changed as longer-lived isotopes of a particular elements has been found in nature, or as improved half-life values of an element's isotopes might cause a shift in the longest-lived isotope from one mass number to another. In the 1957 Report of the Atomic Weights Commission, it was decided to discontinue the listing of the mass number in the Atomic Weights Table on the grounds that the kind of information supplied by the mass number is inconsistent with the primary purpose of the Table, i.e., to provide accurate values of ''these constants'' for use in chemical calculations. In addition to the Table of Atomic Weights, the Commission included an auxiliary Table of Radioactive Elements for the first time, where the entry would be the isotope of that element which was most stable, i.e., it had the longest known half-life. In their 1973 report, the Commission noted that the users of the Atomic Weights Table were dissatisfied with the omission of values in the Table for some elements and it was decided to reintroduce the mass number for elements. In their 1983 report, the Commission decided that radioactive elements were considered to lack a characteristic terrestrial isotopic composition, from which an atomic weight value could be calculated to

  7. DEEP WATER ISOTOPIC CURRENT ANALYZER

    DOEpatents

    Johnston, W.H.

    1964-04-21

    A deepwater isotopic current analyzer, which employs radioactive isotopes for measurement of ocean currents at various levels beneath the sea, is described. The apparatus, which can determine the direction and velocity of liquid currents, comprises a shaft having a plurality of radiation detectors extending equidistant radially therefrom, means for releasing radioactive isotopes from the shaft, and means for determining the time required for the isotope to reach a particular detector. (AEC)

  8. Measurement of the Abundance of Radioactive Be-10 and Other Light Isotopes in Cosmic Radiation Up to 2 GeV /Nucleon with the Balloon-Borne Instrument Isomax

    NASA Technical Reports Server (NTRS)

    Hams, T.; Barbier, L. M.; Bremerich, M.; Christian, E. R.; deNolfo, G. A.; Geier, S.; Goebel, H.; Gupta, S. K.; Hof, M.; Menn, W.

    2004-01-01

    The Isotope Magnet Experiment (ISOMAX), a balloon-borne superconducting magnet spectrometer, was designed to measure the isotopic composition of the light isotopes (3 les than or = Z less than or = 8) of cosmic radiation up to 4 GeV/nucleon with a mass resolution of better than 0.25 amu by using the velocity versus rigidity technique. To achieve this stringent mass resolution, ISOMAX was composed of three major detector systems: a magnetic rigidity spectrometer with a precision drift chamber tracker in conjunction with a three-layer time-of-flight system, and two silica-aerogel Cerenkov counters for velocity determination. A special emphasis of the ISOMAX program was the accurate measurement of radioactive Be-10 with respect to its stable neighbor isotope Be-9, which provides important constraints on the age of cosmic rays in the Galaxy. ISOMAX had its first balloon flight on 1998 August 4-5 from Lynn Lake, Manitoba, Canada. Thirteen hours of data were recorded during this flight at a residual atmosphere of less than 5 g/sq cm. The isotopic ratio at the top of the atmosphere for Be-10/Be-9 was measured to be 0.195 +/- 0.036 (statistical) +/- 0.039 (systematic) between 0.26 and 1.03 GeV/nucleon and 0.317 +/- 0.109(statistical) +/- 0.042(systematic) between 1.13 and 2.03 GeV/nucleon. This is the first measurement of its kind above l GeV/nucleon. ISOMAX results tend to be higher than predictions from current propagation models. In addition to the beryllium results, we report the isotopic ratios of neighboring lithium and boron in the energy range of the time-of-flight system (up to approx. 1 GeV/nucleon). The lithium and boron ratios agree well with existing data and model predictions at similar energies.

  9. Simultaneous determination of PPCPs, EDCs, and artificial sweeteners in environmental water samples using a single-step SPE coupled with HPLC-MS/MS and isotope dilution.

    PubMed

    Tran, Ngoc Han; Hu, Jiangyong; Ong, Say Leong

    2013-09-15

    A high-throughput method for the simultaneous determination of 24 pharmaceuticals and personal care products (PPCPs), endocrine disrupting chemicals (EDCs) and artificial sweeteners (ASs) was developed. The method was based on a single-step solid phase extraction (SPE) coupled with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and isotope dilution. In this study, a single-step SPE procedure was optimized for simultaneous extraction of all target analytes. Good recoveries (≥ 70%) were observed for all target analytes when extraction was performed using Chromabond(®) HR-X (500 mg, 6 mL) cartridges under acidic condition (pH 2). HPLC-MS/MS parameters were optimized for the simultaneous analysis of 24 PPCPs, EDCs and ASs in a single injection. Quantification was performed by using 13 isotopically labeled internal standards (ILIS), which allows correcting efficiently the loss of the analytes during SPE procedure, matrix effects during HPLC-MS/MS and fluctuation in MS/MS signal intensity due to instrument. Method quantification limit (MQL) for most of the target analytes was below 10 ng/L in all water samples. The method was successfully applied for the simultaneous determination of PPCPs, EDCs and ASs in raw wastewater, surface water and groundwater samples collected in a local catchment area in Singapore. In conclusion, the developed method provided a valuable tool for investigating the occurrence, behavior, transport, and the fate of PPCPs, EDCs and ASs in the aquatic environment.

  10. Table of radioactive elements

    SciTech Connect

    Holden, N.E.

    1985-01-01

    As has been the custom in the past, the Commission publishes a table of relative atomic masses and halflives of selected radionuclides. The information contained in this table will enable the user to calculate the atomic weight for radioactive materials with a variety of isotopic compositions. The atomic masses have been taken from the 1984 Atomic Mass Table. Some of the halflives have already been documented.

  11. Radioactivity of Consumer Products

    NASA Astrophysics Data System (ADS)

    Peterson, David; Jokisch, Derek; Fulmer, Philip

    2006-11-01

    A variety of consumer products and household items contain varying amounts of radioactivity. Examples of these items include: FiestaWare and similar glazed china, salt substitute, bananas, brazil nuts, lantern mantles, smoke detectors and depression glass. Many of these items contain natural sources of radioactivity such as Uranium, Thorium, Radium and Potassium. A few contain man-made sources like Americium. This presentation will detail the sources and relative radioactivity of these items (including demonstrations). Further, measurements of the isotopic ratios of Uranium-235 and Uranium-238 in several pieces of china will be compared to historical uses of natural and depleted Uranium. Finally, the presenters will discuss radiation safety as it pertains to the use of these items.

  12. Determining the isotopic compositions of uranium and fission products in radioactive environmental microsamples using laser ablation ICP-MS with multiple ion counters.

    PubMed

    Boulyga, Sergei F; Prohaska, Thomas

    2008-01-01

    This paper presents the application of a multicollector inductively coupled plasma mass spectrometer (MC-ICP-MS)--a Nu Plasma HR--equipped with three ion-counting multipliers and coupled to a laser ablation system (LA) for the rapid and sensitive determination of the 235U/238U, 236U/238U, 145Nd/143Nd, 146Nd/143Nd, 101Ru/(99Ru+99Tc) and 102Ru/(99Ru+99Tc) isotope ratios in microsamples collected in the vicinity of Chernobyl. Microsamples with dimensions ranging from a hundred mum to about 1 mm and with surface alpha activities of 3-38 mBq were first identified using nuclear track radiography. U, Nd and Ru isotope systems were then measured sequentially for the same microsample by LA-MC-ICP-MS. The application of a zoom ion optic for aligning the ion beams into the ion counters allows fast switching between different isotope systems, which enables all of the abovementioned isotope ratios to be measured for the same microsample within a total analysis time of 15-20 min (excluding MC-ICP-MS optimization and calibration). The 101Ru/(99Ru+99Tc) and 102Ru/(99Ru+99Tc) isotope ratios were measured for four microsamples and were found to be significantly lower than the natural ratios, indicating that the microsamples were contaminated with the corresponding fission products (Ru and Tc). A slight depletion in 146Nd of about 3-5% was observed in the contaminated samples, but the Nd isotopic ratios measured in the contaminated samples coincided with natural isotopic composition within the measurement uncertainty, as most of the Nd in the analyzed samples originates from the natural soil load of this element. The 235U/238U and 236U/238U isotope ratios were the most sensitive indicators of irradiated uranium. The present work yielded a significant variation in uranium isotope ratios in microsamples, in contrast with previously published results from the bulk analysis of contaminated samples originating from the vicinity of Chernobyl. Thus, the 235U/238U ratios measured in ten

  13. Assessment of natural and artificial radioactivity levels and radiation hazards and their relation to heavy metals in the industrial area of Port Said city, Egypt.

    PubMed

    Attia, T E; Shendi, E H; Shehata, M A

    2015-02-01

    A detailed gamma ray spectrometry survey was carried out to make an action in environmental impact assessment of urbanization and industrialization on Port Said city, Egypt. The concentrations of the measured radioelements U-238, Th-232 in ppm, and K-40 %, in addition to the total counts of three selected randomly dumping sites (A, B, and C) were mapped. The concentration maps represent a base line for the radioactivity in the study area in order to detect any future radioactive contamination. These concentrations are ranging between 0.2 and 21 ppm for U-238 and 0.01 to 13.4 ppm for Th-232 as well as 0.15 to 3.8 % for K-40, whereas the total count values range from 8.7 to 123.6 uR. Moreover, the dose rate was mapped using the same spectrometer and survey parameters in order to assess the radiological effect of these radioelements. The dose rate values range from 0.12 to 1.61 mSv/year. Eighteen soil samples were collected from the sites with high radioelement concentrations and dose rates to determine the activity concentrations of Ra-226, Th-232, and K-40 using HPGe spectrometer. The activity concentrations of Ra-226, Th-232, and K-40 in the measured samples range from 18.03 to 398.66 Bq kg(-1), 5.28 to 75.7 Bq kg(-1), and 3,237.88 to 583.12 Bq kg(-1), respectively. In addition to analyze heavy metal for two high reading samples (a 1 and a 10) which give concentrations of Cd and Zn elements (a 1 40 ppm and a 10 42 ppm) and (a 1 0.90 ppm and a 10 0.97 ppm), respectively, that are in the range of phosphate fertilizer products that suggested a dumped man-made waste in site A. All indicate that the measured values for the soil samples in the two sites of three falls within the world ranges of soil in areas with normal levels of radioactivity, while site A shows a potential radiological risk for human beings, and it is important to carry out dose assessment program with a specifically detailed monitoring program periodically.

  14. Measurements of radioactive contaminants in semiconductor materials

    NASA Astrophysics Data System (ADS)

    Gordon, Michael S.; Rodbell, Kenneth P.; Murray, Conal E.; McNally, Brendan D.

    2016-12-01

    The emission of alpha particles from materials used to manufacture semiconductors can contribute substantially to the single-event upset rate. The alpha particles originate from contamination in the materials, or from radioactive isotopes, themselves. In this review paper, we discuss the sources of the radioactivity and the measurement methods to detect the emitted particles.

  15. Soil-to-plant transfer factors of radioactive Ca, Sm and Pd isotopes: critical assessment of the use of analogies to derive best-estimates from existing non-specific data.

    PubMed

    Henner, Pascale; Hurtevent, Pierre; Thiry, Yves

    2014-10-01

    (45)Ca, (151)Sm and (107)Pd are three radionuclides present in low to intermediate in activity radioactive wastes for which no soil-to-plant Transfer Factors (TF) values are available to be used in biosphere models for Ecological Risk Assessment. In the absence of specific radioecological studies, this work reviews and analyzes the existing literature for stable isotopes of Pd, Sm and Ca in order to derive best estimates for TF values that could be used as Transfer Factors. Alternative methods of extrapolation are also critically assessed. The values have been classified according to climatic zone, plant class and soil type for each element. The overall geometric mean TF values (for all plants and conditions) was calculated as 8.4E-02 for Pd, for which the value of radioRu in TRS-472 is also available. The mean TF for Sm was 4.2E-04. This value was lower than the TF values for radioactive Ce that are proposed as alternative values for Sm in TRS-472. The former may be relevant for long term assessments and the latter could possibly used to describe the short term (151)Sm post-release behaviour. The mean value for Ca is 2.3E-01 but varies considerably among plants of a given class due to the variety of plant Ca uptake behaviors. Alternatively, to limit this variability, Ca data content for dry plant matter, as analyzed using the phylogenetic method, could be used to derive TF values if the conservation of isotopic ratio of (45)Ca to stable Ca in soils and in plants hypothesis is taken into account. The TF for Ca in sub-tropical zones is 10-fold lower than in temperate zones. There is a lot of data available about exchangeable Ca in soil, which mean that we could calculate an available TF. The analysis shows that Ca bioavailability is also a key factor within transfer.

  16. Biodegradability of algal-derived organic matter in a large artificial lake by using stable isotope tracers.

    PubMed

    Lee, Yeonjung; Lee, Bomi; Hur, Jin; Min, Jun-Oh; Ha, Sun-Yong; Ra, Kongtae; Kim, Kyung-Tae; Shin, Kyung-Hoon

    2016-05-01

    In order to understand the biodegradability of algal-derived organic matter, biodegradation experiments were conducted with (13)C and (15)N-labeled natural phytoplankton and periphytic algal populations in experimental conditions for 60 days. Qualitative changes in the dissolved organic matter were also determined using parallel factor analysis and the stable carbon isotopic composition of the hydrophobic dissolved organic matter through the experimental period. Although algal-derived organic matter is considered to be easily biodegradable, the initial amounts of total organic carbon newly produced by phytoplankton and periphytic algae remained approximately 16 and 44 % after 60 days, respectively, and about 22 and 43 % of newly produced particulate nitrogen remained. Further, the dissolved organic carbon derived from both algal populations increased significantly after 60 days. Although the dissolved organic matter gradually became refractory, the contributions of the algal-derived organic matter to the dissolved organic matter and hydrophobic dissolved organic matter increased. Our laboratory experimental results suggest that algal-derived organic matter produced by phytoplankton and periphytic algae could contribute significantly to the non-biodegradable organic matter through microbial transformations.

  17. Theoretical study on production of heavy neutron-rich isotopes around the N = 126 shell closure in radioactive beam induced transfer reactions

    NASA Astrophysics Data System (ADS)

    Zhu, Long; Su, Jun; Xie, Wen-Jie; Zhang, Feng-Shou

    2017-04-01

    In order to produce more unknown neutron-rich nuclei around N = 126, the transfer reactions 136Xe + 198Pt, 136-144Xe + 208Pb, and 132Sn + 208Pb are investigated within the framework of the dinuclear system (DNS) model. The influence of neutron excess of projectile on production cross sections of target-like products is studied through the reactions 136,144Xe + 208Pb. We find that the radioactive projectile 144Xe with much larger neutron excess is favorable to produce neutron-rich nuclei with charge number less than the target rather than produce transtarget nuclei. The incident energy dependence of yield distributions of fragments in the reaction 132Sn + 208Pb are also studied. The production cross sections of neutron-rich nuclei with Z = 72- 77 are predicted in the reactions 136-144Xe + 208Pb and 132Sn + 208Pb. It is noticed that the production cross sections of unknown neutron-rich nuclei in the reaction 144Xe + 208Pb are at least two orders of magnitude larger than those in the reaction 136Xe + 208Pb. The radioactive beam induced transfer reactions 139,144Xe + 208Pb, considering beam intensities proposed in SPIRAL2 (Production System of Radioactive Ion and Acceleration On-Line) project as well, for production of neutron-rich nuclei around the N = 126 shell closure are investigated for the first time. It is found that, in comparison to the stable beam 136Xe, the radioactive beam 144Xe shows great advantages for producing neutron-rich nuclei with N = 126 and the advantages get more obvious for producing nuclei with less charge number.

  18. Radioactive Wastes.

    PubMed

    Choudri, B S; Baawain, Mahad

    2016-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2015. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes.

  19. Radioactive Wastes.

    PubMed

    Choudri, B S; Baawain, Mahad

    2015-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2014. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes.

  20. Radioactive Wastes.

    PubMed

    Choudri, B S; Charabi, Yassine; Baawain, Mahad; Ahmed, Mushtaque

    2017-10-01

    Papers reviewed herein present a general overview of radioactive waste related activities around the world in 2016. The current reveiw include studies related to safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation. Further, the review highlights on management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in ecosystem, water and soil alongwith other progress made in the management of radioactive wastes.

  1. Radioactive Wastes.

    PubMed

    Choudri, B S; Baawain, Mahad

    2016-10-01

    Papers reviewed herein present a general overview of radioactive waste activities around the world in 2015. These include safety assessments, decommission and decontamination of nuclear facilities, fusion facilities, transportation and management solutions for the final disposal of low and high level radioactive wastes (LLW and HLW), interim storage and final disposal options for spent fuel (SF), and tritiated wastes, with a focus on environmental impacts due to the mobility of radionuclides in water, soil and ecosystem alongwith other progress made in the management of radioactive wastes.

  2. Radioactive Elements in the Standard Atomic Weights Table.

    SciTech Connect

    Holden,N.E.

    2007-08-04

    In the 1949 Report of the Atomic Weights Commission, a series of new elements were added to the Atomic Weights Table. Since these elements had been produced in the laboratory and were not discovered in nature, the atomic weight value of these artificial products would depend upon the production method. Since atomic weight is a property of an element as it occurs in nature, it would be incorrect to assign an atomic weight value to that element. As a result of that discussion, the Commission decided to provide only the mass number of the most stable (or longest-lived) known isotope as the number to be associated with these entries in the Atomic Weights Table. As a function of time, the mass number associated with various elements has changed as longer-lived isotopes of a particular element has been found in nature, or as improved half-life values of an element's isotopes might cause a shift in the longest-lived isotope from one mass to another. In the 1957 Report of the Atomic Weights Commission, it was decided to discontinue the listing of the mass number in the Atomic Weights Table on the grounds that the kind of information supplied by the mass number is inconsistent with the primary purpose of the Table, i.e., to provide accurate values of 'these constants' for use in various chemical calculations. In addition to the Table of Atomic Weights, the Commission included an auxiliary Table of Radioactive Elements for the first time, where the entry would be the isotope of that element which was the most stable, i.e., the one with the longest known half-life. In their 1973 Report, the Commission noted that the users of the main Table of Atomic Weights were dissatisfied with the omission of values for some elements in that Table and it was decided to reintroduce the mass number for the radioactive elements into the main Table. In their 1983 Report, the Commission decided that radioactive elements were considered to lack a characteristic terrestrial isotopic composition

  3. Overview of the U.S. Department of Energy's Isotope Programs

    SciTech Connect

    Carty, J.

    2004-10-05

    This presentation provides an overview of the U.S. Department of Energy's Isotopes Program. The charter of the Isotope Programs covers the production and sale of radioactive and stable isotopes, associated byproducts, surplus materials, and related isotope services.

  4. Concentrating Radioactivity

    ERIC Educational Resources Information Center

    Herrmann, Richard A.

    1974-01-01

    By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

  5. Simulated Radioactivity

    ERIC Educational Resources Information Center

    Boettler, James L.

    1972-01-01

    Describes the errors in the sugar-cube experiment related to radioactivity as described in Project Physics course. The discussion considers some of the steps overlooked in the experiment and generalizes the theory beyond the sugar-cube stage. (PS)

  6. Radioactivity Calculations

    ERIC Educational Resources Information Center

    Onega, Ronald J.

    1969-01-01

    Three problems in radioactive buildup and decay are presented and solved. Matrix algebra is used to solve the second problem. The third problem deals with flux depression and is solved by the use of differential equations. (LC)

  7. Concentrating Radioactivity

    ERIC Educational Resources Information Center

    Herrmann, Richard A.

    1974-01-01

    By concentrating radioactivity contained on luminous dials, a teacher can make a high reading source for classroom experiments on radiation. The preparation of the source and its uses are described. (DT)

  8. Radioactivity Calculations

    ERIC Educational Resources Information Center

    Onega, Ronald J.

    1969-01-01

    Three problems in radioactive buildup and decay are presented and solved. Matrix algebra is used to solve the second problem. The third problem deals with flux depression and is solved by the use of differential equations. (LC)

  9. Simulated Radioactivity

    ERIC Educational Resources Information Center

    Boettler, James L.

    1972-01-01

    Describes the errors in the sugar-cube experiment related to radioactivity as described in Project Physics course. The discussion considers some of the steps overlooked in the experiment and generalizes the theory beyond the sugar-cube stage. (PS)

  10. Naturally Occurring Radioactive Materials (NORM)

    SciTech Connect

    Gray, P.

    1997-02-01

    This paper discusses the broad problems presented by Naturally Occuring Radioactive Materials (NORM). Technologically Enhanced naturally occuring radioactive material includes any radionuclides whose physical, chemical, radiological properties or radionuclide concentration have been altered from their natural state. With regard to NORM in particular, radioactive contamination is radioactive material in an undesired location. This is a concern in a range of industries: petroleum; uranium mining; phosphorus and phosphates; fertilizers; fossil fuels; forestry products; water treatment; metal mining and processing; geothermal energy. The author discusses in more detail the problem in the petroleum industry, including the isotopes of concern, the hazards they present, the contamination which they cause, ways to dispose of contaminated materials, and regulatory issues. He points out there are three key programs to reduce legal exposure and problems due to these contaminants: waste minimization; NORM assesment (surveys); NORM compliance (training).

  11. Radioactive and magnetic investigations

    NASA Technical Reports Server (NTRS)

    Heye, D.; Beiersdorf, H.

    1979-01-01

    Age and growth pattern determination of manganese nodules were explored. Two methods are discussed: (1) measurement of the presence of radioactive iodine isotopes; which is effective only up to 3.105 years, and (2) measurements of magnetism. The growth rates of three nodules were determined. The surface of the nodule was recent, and the overall age of the nodule could be determined with accuracy of better than 30%. Measurement of paleomagnetic effect was attempted to determine wider age ranges, however, the measured sign changes could not be interpreted as paleomagnetic reversals.

  12. Estimation of 240Pu Mass in a Waste Tank Using Ultra-Sensitive Detection of Radioactive Xenon Isotopes from Spontaneous Fission

    SciTech Connect

    Bowyer, Ted W.; Gesh, Christopher J.; Haas, Derek A.; Hayes, James C.; Mahoney, Lenna A.; Meacham, Joseph E.; Mendoza, Donaldo P.; Olsen, Khris B.; Prinke, Amanda M.; Reid, Bruce D.; Woods, Vincent T.

    2014-12-01

    We report on a technique to detect and quantify the amount of 240Pu in a large tank used to store nuclear waste from plutonium production at the Hanford nuclear site. While the contents of this waste tank are known from previous grab sample measurements, our technique could allow for determination of the amount of 240Pu in the tank without costly sample retrieval and analysis of this highly radioactive material. This technique makes an assumption, which was confirmed, that 240Pu dominates the spontaneous fissions occurring in the tank.

  13. A preliminary assessment on the use of biochar as a soil additive for reducing soil-to-plant uptake of cesium isotopes in radioactively contaminated environments

    SciTech Connect

    Hamilton, Terry F.; Martinelli, Roger E.; Kehl, Steven R.; Hayes, Michael H. B.; Smith, Iris J.; Peters, Sandra K. G.; Tamblin, Michael W.; Schmitt, Cindi L.; Hawk, Daniel

    2015-10-19

    A series of Kd tracer batch experiments were conducted to assess the absorptive-desorption properties of Biochar as a potential agent to selectively sequester labile soil Cs or otherwise help reduce the uptake of Cs isotopes into plants. A parallel experiment was conducted for strontium. Fine-grained fractionated Woodlands tree Biochar was found to have a relatively high affinity for Cs ions (Kd > 100) relative to coral soil (Kd < 10) collected from the Marshall Islands. The Biochar material also contains an abundance of K (and Mg). These findings support a hypothesis that the addition of Biochar as a soil amendment may provide a simple yet effective method for reducing soil-to-plant transfer of Cs isotopes in contaminated environments.

  14. Stable and radioactive carbon in forest soils of Chhattisgarh, Central India: Implications for tropical soil carbon dynamics and stable carbon isotope evolution

    NASA Astrophysics Data System (ADS)

    Laskar, A. H.; Yadava, M. G.; Ramesh, R.

    2016-06-01

    Soils from two sites viz. Kotumsar and Tirathgarh, located ∼5 km apart in a tropical reserve forest (18°52‧N, 81°56‧E) in central India, have been explored for soil organic carbon (SOC) content, its mean residence time (MRT) and the evolution of stable carbon isotopic composition (δ13C). SOC stocks in the upper 30 cm of soil layers are ∼5.3 kg/m2 and ∼3.0 kg/m2; in the upper 110 m are ∼10.7 kg/m2 and ∼7.8 kg/m2 at Kotumsar and Tirathgarh, respectively. SOC decreases with increasing depth. Bomb carbon signature is observed in the upper ∼10 cm. Organic matters in the top soil layers (0-10 cm) have MRTs of the order of a century which increases gradually with depths, reaching 3500-5000 yrs at ∼100 cm. δ13C values of SOC increase with depth, the carbon isotopic fractionation is obtained to be -1.2‰ and -3‰ for soils at Kotumsar and Tirathgarh, respectively, confirmed using Rayleigh isotopic fractionation model. The evolution of δ13C in soils was also studied using a modified Rayleigh fractionation model incorporating a continuous input into the reservoir: the depth profiles of δ13C for SOC show that the input organic matter from surface into the deeper soil layers is either insignificant or highly labile and decomposes quite fast in the top layers, thus making little contribution to the residual biomasses of the deeper layers. This is an attempt to understand the distillation processes that take place in SOC, assess the extent of decomposition by microbes and effect of percolation of fresh organic matter into dipper soil layers which are important for stable isotope based paleoclimate and paleovegetation reconstruction and understanding the dynamics of organic carbon in soils.

  15. Metrological Determination of Natural Radioactive Isotopes {sup 226}Ra, {sup 228}Ra and {sup 210}Pb by Means of Ge Detector

    SciTech Connect

    Almeida, Maria Candida M. de; Delgado, Jose U.; Poledna, Roberto; Oliveira, Estela Maria de; Silva, Ronaldo L. da

    2008-08-07

    A metrological method to determine the activity per mass unity (activity concentration) of {sup 226}Ra and {sup 210}Pb ({sup 238}U decay series) and {sup 228}Ra ({sup 232}Th series) by gamma-ray spectrometers based on hyper-pure coaxial germanium detector was developed. In the soil the {sup 22}Ra (half-life = 1600 years) exhibits the same level of radioactivity as {sup 238}U (half-life 4.5x10{sup 9} years) because of a natural phenomenon called secular equilibrium. {sup 226}Ra decays into {sup 222}Rn (half-life = 3.8 days), a radioactive inert gas. After several days, the {sup 222}Rn naturally decays to {sup 218}Po (half-life = 3 minutes), where finally {sup 210}Pb (half-life = 22 years) is produced. The metrological capability of high-resolution gamma-ray spectrometry for naturally occurring radionuclides at environmental levels is showed, with emphasis on the use of 2 mL standard sources volume in a glass ampoule. Source preparation and calibration procedures are described. Radionuclide standards in an activity range of 10 to 250 Bq/g were produced which can be applied in a variety of environmental sample analysis (water, plant material, sediment, etc.). Uncertainties for {sup 226}Ra and {sup 210}Pb around 3% (k = 1) were obtained.

  16. Process for the Production of Radioactive Substances

    NASA Astrophysics Data System (ADS)

    Fermi, Enrico; Amaldi, Edoardo; Pontecorvo, Bruno; Rasetti, Franco; Segré, Emilio

    In this Patent, a very detailed description of the experimental results, obtained by studying the radioactivity induced in a number of chemical elements by irradiation with slow neutrons, is reported, along with a corresponding theoretical interpretation. It is here emphasized, in order to achieve better efficiencies, the use of neutrons instead of charged particles, as considered in previous works on nuclear reactions. Moreover, since neutrons produced by bombardment of atomic nuclei with artificially accelerated particles have high average energies, a method for slowing down fast neutrons is described, by passing the neutrons through a screen of hydrogenous materials, like water or paraffin. The reduction of the energy of the neutrons is interpreted as due to their collisions against the nuclei or the entire atoms of energy reducing materials. An interpretation is provided for the experimental observations: in the case of a strong induced radio-activity following the absorption of the slow neutrons, the formation of an unstable isotope is assumed, while the formation of a stable nucleus is assumed in case no activation or, at least, no strong activation follows an anomalously large absorption. Particularly interesting is the mention of the possible discovery of "transuranic" elements given in the present Patent. Even here, some caution was adopted about its interpretation, as well as the theoretical interpretation of the effects induced by slow neutrons considered in the paper: "The theoretical statements and explanations are, of course, not conclusive and our invention is in no way dependent upon their correctness. We have found them helpful and give them for the aid of others, but our invention will be equally useful if it should prove that our theoretical conclusions are not altogether correct."1 The original Patent application, Metodo per accrescere il rendimento dei procedimenti per la produzione di radioattività artificiali mediante il bombardamento con

  17. Magnesium and chromium isotope evidence for initial melting by radioactive decay of 26Al and late stage impact-melting of the ureilite parent body

    NASA Astrophysics Data System (ADS)

    van Kooten, Elishevah M. M. E.; Schiller, Martin; Bizzarro, Martin

    2017-07-01

    Polymict ureilites are meteoritic breccias that provide insights into the differentiation history of the ureilite parent body. We have sampled a total of 24 clasts from the polymict ureilite Dar al Gani 319, representing a variety of lithologies such as mantle residues, cumulates and crustal fragments that are genetically related to monomict ureilites. In addition, we sampled four non-indigenous dark clasts and two chondrule-containing clasts from the same meteorite. We report on the petrology and the bulk mass-dependent and mass-independent magnesium and chromium isotope systematics of these clasts. The DaG 319 polymict ureilite consists predominantly of clasts related to Main Group ureilite residues (MG clasts) with varying Mg#s (0.74-0.91), as well as a significant fraction of olivine-orthopyroxene clasts related to Hughes Type ureilites (HT clasts) with consistently high Mg#s (∼0.89). In addition, DaG 319 contains less abundant feldspathic clasts that are thought to represent melts derived from the ureilite mantle. A significant mass-dependent Mg-isotope fractionation totaling Δμ25 Mg = ∼450 ppm was found between isotopically light feldspathic clasts (μ25 Mg = -305 ± 25 to 15 ± 12 ppm), MG clasts (μ25 Mg = -23 ± 51 ppm) and HT clasts (μ25 Mg = 157 ± 21 ppm). We suggest that this isotopic offset is the result of equilibrium isotope fractionation during melting in the presence of an isotopically light magnesite component. We propose Mg-carbonates to be stable in the upper ureilite mantle, and pure carbon phases such as graphite to be stable at higher pressures. This is consistent with HT clasts lacking carbon-related phases, whereas MG clasts contain abundant carbon. The timing of differentiation events for the ureilitic clasts are constrained by high precision 53Mn-53Cr systematics and 26Al-26Mg model ages. We show that a dichotomy of ages exist between the differentiation of main group ureilite residues and HT cumulates rapidly after CAI formation

  18. RADIOACTIVE BATTERY

    DOEpatents

    Birden, J.H.; Jordan, K.C.

    1959-11-17

    A radioactive battery which includes a capsule containing the active material and a thermopile associated therewith is presented. The capsule is both a shield to stop the radiations and thereby make the battery safe to use, and an energy conventer. The intense radioactive decay taking place inside is converted to useful heat at the capsule surface. The heat is conducted to the hot thermojunctions of a thermopile. The cold junctions of the thermopile are thermally insulated from the heat source, so that a temperature difference occurs between the hot and cold junctions, causing an electrical current of a constant magnitude to flow.

  19. Natural and artificial nobel gas hydrologic tracers

    SciTech Connect

    Hudson, G.B.

    1994-06-01

    Noble gas isotopes provide opportunities for ground water tracing. Both naturally occurring tracers and artificially injected tracers can be used. The equilibration of water with the earth`s atmosphere records the temperature and atmospheric pressure during ground water recharge. This temperature/pressure record can be used to distinguish cold recharge from warmer recharge with a resolution of 1-2 C temperature and 500m in altitude. The radioactive decay of U and Th produce large concentrations of 4He in old ground water and this 4He signature can be useful in tracing the small addition of old water (>10,000 yr.) to young water (<100 yr.). The decay of 3H present either form nuclear testing or cosmic ray interactions leads to detectable amounts of 3He in young ground water (<50 yr.). By measuring both 3H and 3He, the mean age of the 3H in the water can be calculated. In addition to these natural tracers, isotopically enriched noble gas isotopes are readily available at low cost and can be used an non-hazardous water tracers. This inert, persistent, and harmless tracing technique can used in many situations at a cost of about one dollar per million gallons of water traced.

  20. Radioactive waste management information for 1996 and record-to-date

    SciTech Connect

    French, D.L.; Lisee, D.J.; Taylor, K.A.

    1997-07-01

    This document presents detailed data, bar graphs, and pie charts on volume, radioactivity, isotopic identity, origin, and status of radioactive waste for calendar year 1996. It also summarizes the radioactive waste data records compiled from 1952 to present for the Idaho National Engineering and Environmental Laboratory (INEEL). The data presented are from the INEEL Radioactive Waste Management Information System.

  1. Radioactive waste management information for 1993 and record-to-date

    SciTech Connect

    Taylor, K.A.

    1994-07-01

    This document presents detailed data, bar graphs, and pie charts on volume, radioactivity, isotopic identity, origin, and decay status of radioactive waste for the calendar year 1993. It also summarizes the radioactive waste data records compiled from 1952 to present for the Idaho National Engineering Laboratory (INEL). The data presented are from the INEL Radioactive Waste Management Information System.

  2. Radioactive Waste.

    ERIC Educational Resources Information Center

    Blaylock, B. G.

    1978-01-01

    Presents a literature review of radioactive waste disposal, covering publications of 1976-77. Some of the studies included are: (1) high-level and long-lived wastes, and (2) release and burial of low-level wastes. A list of 42 references is also presented. (HM)

  3. Radioactive Waste.

    ERIC Educational Resources Information Center

    Blaylock, B. G.

    1978-01-01

    Presents a literature review of radioactive waste disposal, covering publications of 1976-77. Some of the studies included are: (1) high-level and long-lived wastes, and (2) release and burial of low-level wastes. A list of 42 references is also presented. (HM)

  4. Cosmic radioactivity and INTEGRAL results

    SciTech Connect

    Diehl, Roland

    2014-05-02

    Gamma-ray lines from radioactive decay of unstable isotopes co-produced by nucleosynthesis in massive stars and supernova have been measured since more than thirty years. Over the past ten years, INTEGRAL complemented the first sky survey made by COMPTEL. The {sup 26}A1 isotope with 1 My decay time had been first direct proof of currently-ongoing nucleosynthesis in our Galaxy. This has now become a tool to study the ∼My history of specific source regions, such as massive-star groups and associations in nearby regions which can be discriminated from the galactic-plane background, and the inner Galaxy, where Doppler shifted lines add to the astronomical information about bar and spiral structure. Recent findings suggest that superbubbles show a remarkable asymmetry, on average, in the spiral arms of our galaxy. {sup 60}Fe is co-produced by the sources of {sup 26}A1, and the isotopic ratio from their nucleosynthesis encodes stellar-structure information. Annihilation gamma-rays from positrons in interstellar space show a puzzling bright and extended source region central to our Galaxy, but also may be partly related to nucleosynthesis. {sup 56}Ni and {sup 44}Ti isotope gamma-rays have been used to constrain supernova explosion mechanisms. Here we report latest results using the accumulated multi-year database of INTEGRAL observations, and discuss their astrophysical interpretations, connecting to other traces of cosmic radioactivity and to other cosmic messengers.

  5. Nuclear astrophysics with radioactive ions at FAIR

    NASA Astrophysics Data System (ADS)

    Reifarth, R.; Altstadt, S.; Göbel, K.; Heftrich, T.; Heil, M.; Koloczek, A.; Langer, C.; Plag, R.; Pohl, M.; Sonnabend, K.; Weigand, M.; Adachi, T.; Aksouh, F.; Al-Khalili, J.; AlGarawi, M.; AlGhamdi, S.; Alkhazov, G.; Alkhomashi, N.; Alvarez-Pol, H.; Alvarez-Rodriguez, R.; Andreev, V.; Andrei, B.; Atar, L.; Aumann, T.; Avdeichikov, V.; Bacri, C.; Bagchi, S.; Barbieri, C.; Beceiro, S.; Beck, C.; Beinrucker, C.; Belier, G.; Bemmerer, D.; Bendel, M.; Benlliure, J.; Benzoni, G.; Berjillos, R.; Bertini, D.; Bertulani, C.; Bishop, S.; Blasi, N.; Bloch, T.; Blumenfeld, Y.; Bonaccorso, A.; Boretzky, K.; Botvina, A.; Boudard, A.; Boutachkov, P.; Boztosun, I.; Bracco, A.; Brambilla, S.; Briz Monago, J.; Caamano, M.; Caesar, C.; Camera, F.; Casarejos, E.; Catford, W.; Cederkall, J.; Cederwall, B.; Chartier, M.; Chatillon, A.; Cherciu, M.; Chulkov, L.; Coleman-Smith, P.; Cortina-Gil, D.; Crespi, F.; Crespo, R.; Cresswell, J.; Csatlós, M.; Déchery, F.; Davids, B.; Davinson, T.; Derya, V.; Detistov, P.; Diaz Fernandez, P.; DiJulio, D.; Dmitry, S.; Doré, D.; Dueñas, J.; Dupont, E.; Egelhof, P.; Egorova, I.; Elekes, Z.; Enders, J.; Endres, J.; Ershov, S.; Ershova, O.; Fernandez-Dominguez, B.; Fetisov, A.; Fiori, E.; Fomichev, A.; Fonseca, M.; Fraile, L.; Freer, M.; Friese, J.; Borge, M. G.; Galaviz Redondo, D.; Gannon, S.; Garg, U.; Gasparic, I.; Gasques, L.; Gastineau, B.; Geissel, H.; Gernhäuser, R.; Ghosh, T.; Gilbert, M.; Glorius, J.; Golubev, P.; Gorshkov, A.; Gourishetty, A.; Grigorenko, L.; Gulyas, J.; Haiduc, M.; Hammache, F.; Harakeh, M.; Hass, M.; Heine, M.; Hennig, A.; Henriques, A.; Herzberg, R.; Holl, M.; Ignatov, A.; Ignatyuk, A.; Ilieva, S.; Ivanov, M.; Iwasa, N.; Jakobsson, B.; Johansson, H.; Jonson, B.; Joshi, P.; Junghans, A.; Jurado, B.; Körner, G.; Kalantar, N.; Kanungo, R.; Kelic-Heil, A.; Kezzar, K.; Khan, E.; Khanzadeev, A.; Kiselev, O.; Kogimtzis, M.; Körper, D.; Kräckmann, S.; Kröll, T.; Krücken, R.; Krasznahorkay, A.; Kratz, J.; Kresan, D.; Krings, T.; Krumbholz, A.; Krupko, S.; Kulessa, R.; Kumar, S.; Kurz, N.; Kuzmin, E.; Labiche, M.; Langanke, K.; Lazarus, I.; Le Bleis, T.; Lederer, C.; Lemasson, A.; Lemmon, R.; Liberati, V.; Litvinov, Y.; Löher, B.; Lopez Herraiz, J.; Münzenberg, G.; Machado, J.; Maev, E.; Mahata, K.; Mancusi, D.; Marganiec, J.; Martinez Perez, M.; Marusov, V.; Mengoni, D.; Million, B.; Morcelle, V.; Moreno, O.; Movsesyan, A.; Nacher, E.; Najafi, M.; Nakamura, T.; Naqvi, F.; Nikolski, E.; Nilsson, T.; Nociforo, C.; Nolan, P.; Novatsky, B.; Nyman, G.; Ornelas, A.; Palit, R.; Pandit, S.; Panin, V.; Paradela, C.; Parkar, V.; Paschalis, S.; Pawłowski, P.; Perea, A.; Pereira, J.; Petrache, C.; Petri, M.; Pickstone, S.; Pietralla, N.; Pietri, S.; Pivovarov, Y.; Potlog, P.; Prokofiev, A.; Rastrepina, G.; Rauscher, T.; Ribeiro, G.; Ricciardi, M.; Richter, A.; Rigollet, C.; Riisager, K.; Rios, A.; Ritter, C.; Rodriguez Frutos, T.; Rodriguez Vignote, J.; Röder, M.; Romig, C.; Rossi, D.; Roussel-Chomaz, P.; Rout, P.; Roy, S.; Söderström, P.; Saha Sarkar, M.; Sakuta, S.; Salsac, M.; Sampson, J.; Sanchez, J.; Rio Saez, del; Sanchez Rosado, J.; Sanjari, S.; Sarriguren, P.; Sauerwein, A.; Savran, D.; Scheidenberger, C.; Scheit, H.; Schmidt, S.; Schmitt, C.; Schnorrenberger, L.; Schrock, P.; Schwengner, R.; Seddon, D.; Sherrill, B.; Shrivastava, A.; Sidorchuk, S.; Silva, J.; Simon, H.; Simpson, E.; Singh, P.; Slobodan, D.; Sohler, D.; Spieker, M.; Stach, D.; Stan, E.; Stanoiu, M.; Stepantsov, S.; Stevenson, P.; Strieder, F.; Stuhl, L.; Suda, T.; Sümmerer, K.; Streicher, B.; Taieb, J.; Takechi, M.; Tanihata, I.; Taylor, J.; Tengblad, O.; Ter-Akopian, G.; Terashima, S.; Teubig, P.; Thies, R.; Thoennessen, M.; Thomas, T.; Thornhill, J.; Thungstrom, G.; Timar, J.; Togano, Y.; Tomohiro, U.; Tornyi, T.; Tostevin, J.; Townsley, C.; Trautmann, W.; Trivedi, T.; Typel, S.; Uberseder, E.; Udias, J.; Uesaka, T.; Uvarov, L.; Vajta, Z.; Velho, P.; Vikhrov, V.; Volknandt, M.; Volkov, V.; von Neumann-Cosel, P.; von Schmid, M.; Wagner, A.; Wamers, F.; Weick, H.; Wells, D.; Westerberg, L.; Wieland, O.; Wiescher, M.; Wimmer, C.; Wimmer, K.; Winfield, J. S.; Winkel, M.; Woods, P.; Wyss, R.; Yakorev, D.; Yavor, M.; Zamora Cardona, J.; Zartova, I.; Zerguerras, T.; Zgura, M.; Zhdanov, A.; Zhukov, M.; Zieblinski, M.; Zilges, A.; Zuber, K.

    2016-01-01

    The nucleosynthesis of elements beyond iron is dominated by neutron captures in the s and r processes. However, 32 stable, proton-rich isotopes cannot be formed during those processes, because they are shielded from the s-process flow and r-process, β-decay chains. These nuclei are attributed to the p and rp process. For all those processes, current research in nuclear astrophysics addresses the need for more precise reaction data involving radioactive isotopes. Depending on the particular reaction, direct or inverse kinematics, forward or time-reversed direction are investigated to determine or at least to constrain the desired reaction cross sections. The Facility for Antiproton and Ion Research (FAIR) will offer unique, unprecedented opportunities to investigate many of the important reactions. The high yield of radioactive isotopes, even far away from the valley of stability, allows the investigation of isotopes involved in processes as exotic as the r or rp processes.

  6. ICP-MS for isotope ratio measurement

    USDA-ARS?s Scientific Manuscript database

    The use of stable isotopes in mineral nutrition research has become a fundamental aspect of conducting this research. A gradual transition has occurred, now virtually complete, from radioactive isotope studies to those using stable isotopes. Although primarily used in human research, mineral stable ...

  7. Calculation of the inventory and near-field release rates of radioactivity from neutron-activated metal parts discharged from the high flux isotope reactor and emplaced in solid waste storage area 6 at Oak Ridge National Laboratory

    SciTech Connect

    Kelmers, A.D.; Hightower, J.R.

    1987-05-01

    Emplacement of contaminated reactor components involves disposal in lined and unlined auger holes in soil above the water table. The radionuclide inventory of disposed components was calculated. Information on the composition and weight of the components, as well as reasonable assumptions for the neutron flux fueling use, the time of neutron exposure, and radioactive decay after discharge, were employed in the inventory calculation. Near-field release rates of /sup 152/Eu, /sup 154/Eu, and /sup 155/Eu from control plates and cylinders were calculated for 50 years after emplacement. Release rates of the europium isotopes were uncertain. Two release-rate-limiting models were considered and a range of reasonable values were assumed for the time-to-failure of the auger-hole linear and aluminum cladding and europium solubility in SWSA-6 groundwater. The bounding europium radionuclide near-field release rates peaked at about 1.3 Ci/year total for /sup 152,154,155/Eu in 1987 for the lower bound, and at about 420 Ci/year in 1992 for the upper bound. The near-field release rates of /sup 55/Fe, /sup 59/Ni, /sup 60/Co, and /sup 63/Ni from stainless steel and cobalt alloy components, as well as of /sup 10/Be, /sup 41/Ca, and /sup 55/Fe from beryllium reflectors, were calculated for the next 100 years, assuming bulk waste corrosion was the release-rate-limiting step. Under the most conservative assumptions for the reflectors, the current (1986) total radionuclide release rate was calculated to be about 1.2 x 10/sup -4/ Ci/year, decreasing by 1992 to a steady release of about 1.5 x 10/sup -5/ Ci/year due primarily to /sup 41/Ca. 50 refs., 13 figs., 8 tabs.

  8. Laser photodetachment of radioactive 128I‑

    NASA Astrophysics Data System (ADS)

    Rothe, Sebastian; Sundberg, Julia; Welander, Jakob; Chrysalidis, Katerina; Day Goodacre, Thomas; Fedosseev, Valentin; Fiotakis, Spyridon; Forstner, Oliver; Heinke, Reinhard; Johnston, Karl; Kron, Tobias; Köster, Ulli; Liu, Yuan; Marsh, Bruce; Ringvall-Moberg, Annie; Rossel, Ralf Erik; Seiffert, Christoph; Studer, Dominik; Wendt, Klaus; Hanstorp, Dag

    2017-10-01

    The first experimental investigation of the electron affinity (EA) of a radioactive isotope has been conducted at the CERN-ISOLDE radioactive ion beam facility. The EA of the radioactive iodine isotope 128I (t 1/2 = 25 min) was determined to be 3.059 052(38) eV. The experiment was conducted using the newly developed Gothenburg ANion Detector for Affinity measurements by Laser PHotodetachment (GANDALPH) apparatus, connected to a CERN-ISOLDE experimental beamline. 128I was produced in fission induced by 1.4 GeV protons striking a thorium/tantalum foil target and then extracted as singly charged negative ions at a beam energy of 20 keV. Laser photodetachment of the fast ion beam was performed in a collinear geometry inside the GANDALPH chamber. Neutral atoms produced in the photodetachment process were detected by allowing them to impinge on a glass surface, creating secondary electrons which were then detected using a channel electron multiplier. The photon energy of the laser was tuned across the threshold of the photodetachment process and the detachment threshold data were fitted to a Wigner law function in order to extract the EA. This first successful demonstration of photodetachment at an isotope separator on line facility opens up the opportunity for future studies of the fundamental properties of negatively charged radioactive isotopes such as the EA of astatine and polonium.

  9. Carbon isotope exchange between gaseous CO2 and thin solution films: Artificial cave experiments and a complete diffusion-reaction model

    NASA Astrophysics Data System (ADS)

    Hansen, Maximilian; Scholz, Denis; Froeschmann, Marie-Louise; Schöne, Bernd R.; Spötl, Christoph

    2017-08-01

    Speleothem stable carbon isotope (δ13C) records provide important paleoclimate and paleo-environmental information. However, the interpretation of these records in terms of past climate or environmental change remains challenging because of various processes affecting the δ13C signals. A process that has only been sparsely discussed so far is carbon isotope exchange between the gaseous CO2 of the cave atmosphere and the dissolved inorganic carbon (DIC) contained in the thin solution film on the speleothem, which may be particularly important for strongly ventilated caves. Here we present a novel, complete reaction diffusion model describing carbon isotope exchange between gaseous CO2 and the DIC in thin solution films. The model considers all parameters affecting carbon isotope exchange, such as diffusion into, out of and within the film, the chemical reactions occurring within the film as well as the dependence of diffusion and the reaction rates on isotopic mass and temperature. To verify the model, we conducted laboratory experiments under completely controlled, cave-analogue conditions at three different temperatures (10, 20, 30 °C). We exposed thin (≈0.1 mm) films of a NaHCO3 solution with four different concentrations (1, 2, 5 and 10 mmol/l, respectively) to a nitrogen atmosphere containing a specific amount of CO2 (1000 and 3000 ppmV). The experimentally observed temporal evolution of the pH and δ13C values of the DIC is in good agreement with the model predictions. The carbon isotope exchange times in our experiments range from ca. 200 to ca. 16,000 s and strongly depend on temperature, film thickness, atmospheric pCO2 and the concentration of DIC. For low pCO2 (between 500 and 1000 ppmV, as for strongly ventilated caves), our time constants are substantially lower than those derived in a previous study, suggesting a potentially stronger influence of carbon isotope exchange on speleothem δ13C values. However, this process should only have an

  10. Radioactive decay.

    PubMed

    Groch, M W

    1998-01-01

    When a parent radionuclide decays to its daughter radionuclide by means of alpha, beta, or isomeric transition, the decay follows an exponential form, which is characterized by the decay constant lambda. The decay constant represents the probability per unit time that a single radioatom will decay. The decay equation can be used to provide a useful expression for radionuclide decay, the half-life, the time when 50% of the radioatoms present will have decayed. Radiotracer half-life has direct implications in nuclear imaging, radiation therapy, and radiation safety because radionuclide half-life affects the ability to evaluate tracer kinetics and create appropriate nuclear images and also affects organ, tumor, and whole-body radiation dose. The number of radioatoms present in a sample is equal to the activity, defined as the number of transitions per unit time, divided by the decay constant; the mass of radioatoms present in a sample can be calculated to determine the specific activity (activity per unit mass). The dynamic relationship between the number of parent and daughter atoms present over time may lead to radioactive equilibrium, which takes two forms--secular and transient--and has direct relevance to generator-produced radionuclides.

  11. Radioactive Ion Beam Production Capabilities at the Holifield Radioactive Ion Beam Facility

    SciTech Connect

    Beene, James R; Dowling, Darryl T; Gross, Carl J; Juras, Raymond C; Liu, Yuan; Meigs, Martha J; Mendez, II, Anthony J; Nazarewicz, Witold; Sinclair, John William; Stracener, Daniel W; Tatum, B Alan

    2011-01-01

    The Holifield Radioactive Ion Beam Facility (HRIBF) is a national user facility for research with radioactive ion beams (RIBs) that has been in routine operation since 1996. It is located at Oak Ridge National Laboratory (ORNL) and operated by the ORNL Physics Division. The principal mission of HRIBF is the production of high-quality beams of short-lived radioactive isotopes to support research in nuclear structure physics and nuclear astrophysics. HRIBF is currently unique worldwide in its ability to provide neutron-rich fission fragment beams post-accelerated to energies above the Coulomb barrier for nuclear reactions.

  12. Radioactive Waste Management Information for 1991 and Record-to-Date

    SciTech Connect

    Litteer, D.L.; Peterson, C.N.; Sims, A.M.

    1993-04-01

    This document presents detailed data, bar graphs, and pie charts on volume, radioactivity, isotopic identity, origin, and decay status of radioactive waste for the calendar year 1991. It also summarizes the radiative waste data records compiled from 1952 to present for the Idaho National Engineering Laboratory (INEL). The data presented are from the INEL Radioactive Waste Management Information System.

  13. Volumetric Radioactivity Viewed as Surface Radioactivity for Free Release Assessment Purposes

    SciTech Connect

    Boettinger, W.L.

    1998-07-08

    As a part of the SRS Beneficial Reuse Program, stainless steel radioactive scrap metal is melted, pour into ingots, and roll into sheets. The sheets are then fabricated into boxes and barrels for beneficial reuse. The melting activity is a partial decontamination process. Certain isotopes separate from the melted steel, while others stay in solution. Cobalt-60 is the primary constituent, which remains in solution, and becomes the major contributor to the volumetric radioactivity of the finished products (boxes and barrels). There is currently no ``de minimis`` free release level for volumetrically radioactive material. However, under certain circumstances, pathway analysis can be used (and have been used) to free release volumetrically radioactive material. This paper presents an analysis using empirical data derived from over sixty ``melts``, to demonstrate that the implied surface radioactivity for specific beneficial reuse products is within free release limit. The approach can be applied to other recycled metal products.

  14. Soils: man-caused radioactivity and radiation forecast

    SciTech Connect

    Gablin, Vassily

    2007-07-01

    Available in abstract form only. Full text of publication follows: One of the main tasks of the radiation safety guarantee is non-admission of the excess over critical radiation levels. In Russia they are man-caused radiation levels. Meanwhile any radiation measurement represents total radioactivity. That is why it is hard to assess natural and man-caused contributions to total radioactivity. It is shown that soil radioactivity depends on natural factors including radioactivity of rocks and cosmic radiation as well as man-caused factors including nuclear and non-nuclear technologies. Whole totality of these factors includes unpredictable (non-deterministic) factors - nuclear explosions and radiation accidents, and predictable ones (deterministic) - all the rest. Deterministic factors represent background radioactivity whose trends is the base of the radiation forecast. Non-deterministic factors represent man-caused radiation treatment contribution which is to be controlled. This contribution is equal to the difference in measured radioactivity and radiation background. The way of calculation of background radioactivity is proposed. Contemporary soils are complicated technologically influenced systems with multi-leveled spatial and temporary inhomogeneity of radionuclides distribution. Generally analysis area can be characterized by any set of factors of soil radioactivity including natural and man-caused factors. Natural factors are cosmic radiation and radioactivity of rocks. Man-caused factors are shown on Fig. 1. It is obvious that man-caused radioactivity is due to both artificial and natural emitters. Any result of radiation measurement represents total radioactivity i.e. the sum of activities resulting from natural and man-caused emitters. There is no gauge which could separately measure natural and man-caused radioactivity. That is why it is so hard to assess natural and man-caused contributions to soil radioactivity. It would have been possible if human

  15. Production of radioactive nuclides in inverse reaction kinematics

    NASA Astrophysics Data System (ADS)

    Traykov, E.; Rogachevskiy, A.; Bosswell, M.; Dammalapati, U.; Dendooven, P.; Dermois, O. C.; Jungmann, K.; Onderwater, C. J. G.; Sohani, M.; Willmann, L.; Wilschut, H. W.; Young, A. R.

    2007-03-01

    Efficient production of short-lived radioactive isotopes in inverse reaction kinematics is an important technique for various applications. It is particularly relevant when the isotope of interest is only a few nucleons away from a stable isotope. In this article production via charge exchange and stripping reactions in combination with a magnetic separator is explored. The relation between the separator transmission efficiency, the production yield, and the choice of beam energy is discussed. The results of some exploratory experiments will be presented.

  16. New accelerator to bridge isotope gap

    NASA Astrophysics Data System (ADS)

    Cartlidge, Edwin

    2010-08-01

    The TRIUMF nuclear- and particle-physics lab in British Columbia in Canada is to build an extremely intense electron linear accelerator to produce radioactive isotopes for fundamental research and medicine.

  17. RADIOACTIVE ELEMENTS IN THE STANDARD ATOMIC WEIGHTS TABLE

    SciTech Connect

    Holden, N.E.; Holden, N.; Holden,N.E.

    2011-07-27

    In the 1949 Report of the Atomic Weights Commission, a series of new elements were added to the Atomic Weights Table. Since these elements had been produced in the laboratory and were not discovered in nature, the atomic weight value of these artificial products would depend upon the production method. Since atomic weight is a property of an element as it occurs in nature, it would be incorrect to assign an atomic weight value to that element. As a result of that discussion, the Commission decided to provide only the mass number of the most stable (or longest-lived) known isotope as the number to be associated with these entries in the Atomic Weights Table. As a function of time, the mass number associated with various elements has changed as longer-lived isotopes of a particular element has been found in nature, or as improved half-life values of an element's isotopes might cause a shift in the longest-lived isotope from one mass to another. In the 1957 Report of the Atomic Weights Commission, it was decided to discontinue the listing of the mass number in the Atomic Weights Table on the grounds that the kind of information supplied by the mass number is inconsistent with the primary purpose of the Table, i.e., to provide accurate values of 'these constants' for use in various chemical calculations. In addition to the Table of Atomic Weights, the Commission included an auxiliary Table of Radioactive Elements for the first time, where the entry would be the isotope of that element which was the most stable, i.e., the one with the longest known half-life. In their 1973 Report, the Commission noted that the users of the main Table of Atomic Weights were dissatisfied with the omission of values for some elements in that Table and it was decided to reintroduce the mass number for the radioactive elements into the main Table. In their 1983 Report, the Commission decided that radioactive elements were considered to lack a characteristic terrestrial isotopic composition

  18. The study of natural and artificial radionuclides incorporation in teeth and head bones of animals lived nearby Caetité uranium mine, Brazil.

    PubMed

    Walencik-Łata, A; Kozłowska, B; Mietelski, J W; Szufa, K; Freire, F D; Souza, S O

    2016-10-01

    This study aimed at assessing the incorporation of radionuclides in animals in the proximity of the uranium mine in Caetité, Brazil. In 2014, samples of bovine and equine teeth and skull bones were collected and their contents of natural and artificial isotopes were assessed using nuclear spectrometry techniques. Gamma ray emission from (226,228)Ra and (40)K isotopes was determined using high-purity germanium (HPGe) spectrometry, (90)Sr radioactivity was measured with liquid scintillation, and (234,238)U, (232,230,228)Th, (210)Po and (239+240)Pu radioactivity was assessed with alpha-spectrometry. Prior to the measurements, sample dissolutions and isotope separations were performed. Our results indicate a high (228)Th isotope content in the skull bones and the teeth of animals, up to 179 Bq per kg of ash. The (226)Ra and (228)Ra concentrations were slightly lower. Activity concentrations of other isotopes were significantly lower or below the detection limit. We could not identify sources of technologically enhanced levels of (228)Ra in the area we investigated; therefore we suggest that their origin is natural. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Holifield Radioactive Ion Beam Facility Status

    SciTech Connect

    Stracener, Daniel W; Beene, James R; Dowling, Darryl T; Juras, Raymond C; Liu, Yuan; Meigs, Martha J; Mendez, II, Anthony J; Mueller, Paul Edward; Sinclair, John William; Tatum, B Alan; Sinclair IV, John W

    2009-01-01

    The Holifield Radioactive Ion Beam Facility (HRIBF) at Oak Ridge National Laboratory (ORNL) produces high-quality beams of short-lived radioactive isotopes for nuclear science research, and is currently unique worldwide in the ability to provide neutron-rich fission fragment beams post-accelerated to energies above the Coulomb barrier. HRIBF is undergoing a multi-phase upgrade. Phase I (completed 2005) was construction of the High Power Target Laboratory to provide the on-going Isotope Separator On-Line (ISOL) development program with a venue for testing new targets, ion sources, and radioactive ion beam (RIB) production techniques with high-power beams. Phase II, which is on schedule for completion in September 2009, is the Injector for Radioactive Ion Species 2 (IRIS2), a second RIB production station that will improve facility reliability and accommodate new ion sources, new RIB production targets, and some innovative RIB purification techniques, including laser applications. The Phase III goal is to substantially improve facility performance by replacing or supplementing the Oak Ridge Isochronous Cyclotron (ORIC) production accelerator with either a high-power 25-50 MeV electron accelerator or a high-current multi-beam commercial cyclotron. Either upgrade is applicable to R&D on isotope production for medical or other applications.

  20. Is radioactive decay really exponential?

    NASA Astrophysics Data System (ADS)

    Aston, P. J.

    2012-03-01

    Radioactive decay of an unstable isotope is widely believed to be exponential. This view is supported by experiments on rapidly decaying isotopes but is more difficult to verify for slowly decaying isotopes. The decay of 14C can be calibrated over a period of 12550 years by comparing radiocarbon dates with dates obtained from dendrochronology. It is well known that this approach shows that radiocarbon dates of over 3000 years are in error, which is generally attributed to past variation in atmospheric levels of 14C. We note that predicted atmospheric variation (assuming exponential decay) does not agree with results from modelling, and that theoretical quantum mechanics does not predict exact exponential decay. We give mathematical arguments that non-exponential decay should be expected for slowly decaying isotopes and explore the consequences of non-exponential decay. We propose an experimental test of this prediction of non-exponential decay for 14C. If confirmed, a foundation stone of current dating methods will have been removed, requiring a radical reappraisal both of radioisotope dating methods and of currently predicted dates obtained using these methods.

  1. Reactor radioactive emission monitor

    SciTech Connect

    Jester, W.A.; Mc Master, I.B.; Baratta, A.J.

    1987-05-05

    This patent describes a means for measuring quantities of a selected radioactive component in a stream of radioactive fluid. The means comprise: a first fluid path with a first means for retaining the selected radioactive component mounted in the fluid path for retaining the radioactive component while passing the remainder of the stream of radioactive fluid; a second fluid path with a second means for retaining the selected radioactive component mounted in the second fluid path for retaining the radioactive component while passing the remainder of the stream of the radioactive fluid; first and second detectors for detecting the level of radioactivity emitted by the retained radioactive component in the first and second retaining means; a means for integrating the output of one or more of the detectors as a function of time to measure any increase in the radioactivity emitted by the radioactive component retained by the retaining means, and the increase being representative of the amount of selected radioactive component present in the stream of radioactive fluid.

  2. RADIO-ACTIVE TRANSDUCER

    DOEpatents

    Wanetick, S.

    1962-03-01

    ABS>ure the change in velocity of a moving object. The transducer includes a radioactive source having a collimated beam of radioactive particles, a shield which can block the passage of the radioactive beam, and a scintillation detector to measure the number of radioactive particles in the beam which are not blocked by the shield. The shield is operatively placed across the radioactive beam so that any motion normal to the beam will cause the shield to move in the opposite direction thereby allowing more radioactive particles to reach the detector. The number of particles detected indicates the acceleration. (AEC)

  3. Isotopic discrimination during litter decomposition and delta13C and delta15N soil profiles in a young artificial stand and in an old floodplain forest.

    PubMed

    Gioacchini, Paola; Masia, Andrea; Canaccini, Francesca; Boldreghini, Pietro; Tonon, Giustino

    2006-06-01

    In the present study, rates of litter decomposition and microbial biomass nitrogen were monitored over an 8-month period in a young broadleaf plantation (18 y) and in an old floodplain forest. Moreover, delta13C and delta15N temporal variations within soil profiles were evaluated at both sites. Rates of litter decomposition were higher in spring and autumn than in summer, in both forests. At the end of the observation period the percentage of original litter remaining was not statistically different between the young and the old forest and accounted for 60-70% of the original amount. Microbial biomass nitrogen in the remaining litter and the percentage of litter mass lost during decomposition were positively correlated. The difference in litter quality affected the decomposition rate and also the changes in carbon isotopic composition during the decomposition process. In contrast, 15N isotopic signatures showed a similar trend in the litter of the two forests irrespective of the litter quality. Although delta13Csoil and delta15Nsoil showed considerable temporal variation they increased with depth in the soils of both sites but their seasonal changes did not reflect those of the decomposing litter. Within the same soil horizon, both delta13C and delta15N showed similar seasonal trends in the soils of the two forests, suggesting the involvement of environmental factors acting at regional level, such as soil temperature and rainfall variations, in regulating seasonal delta13C and delta15N soil variations.

  4. The Mean Life Squared Relationship for Abundances of Extinct Radioactivities

    NASA Technical Reports Server (NTRS)

    Lodders, K.; Cameron, A. G. W.

    2004-01-01

    We discovered that the abundances of now extinct radioactivities (relative to stable reference isotopes) in meteorites vary as a function of their mean lifetimes squared. This relationship applies to chondrites, achondrites, and irons but to calcium-aluminum inclusions (CAIs). Certain meteorites contain excesses in isotopic abundances from the decay of radioactive isotopes with half-lives much less than the age of the solar system. These short-lived radioactivities are now extinct, but they were alive when meteorites assembled in the early solar system. The origin of these radioactivities and the processes which control their abundances in the solar nebula are still not well understood. Some clues may come from our finding that the meteoritic abundances of now extinct radioactivities (relative to stable reference isotopes) vary as a function of their mean lifetimes squared. This relationship applies to chondrites, achondrites, and irons, but not to CAIs. This points to at least two different processes establishing the abundances of short-lived isotopes found in the meteoritic record.

  5. Radioactivity in the Great Lakes.

    PubMed

    Joshi, S R

    1991-03-01

    Studies of radioactivity in the Laurentian Great Lakes are reviewed to evaluate the impact of radionuclide dissemination on the world's foremost freshwater aquatic ecosystem. The status of radiologically-degraded areas is also reported. Significant amounts of radioactivity are stored in the basin, which has numerous nuclear reactors as well as uranium mine waste areas. The prevailing low levels of artificially-produced radionuclides, arising largely from previous fallout inputs, provide very little radiation dose to the area residents consuming lake water. The interlake transport of radionuclides is adequately described by existing models, though some refinement of the source term is needed. Revised estimates of fallout over each lake are given, but no data are available to estimate drainage basin contributions. Only limited information is available on the dispersal of radioactive pollutants. The influence of chemical parameters on radionuclide cycling has been extensively investigated in Lake Michigan and, to a lesser degree, in Lake Ontario. The need for developing a radiological objective for fish becomes apparent from an assessment of the very few data collected thus far on the biological and dosimetric aspects. Several research and monitoring needs are also identified.

  6. Stable (206Pb, 207Pb, 208Pb) and radioactive (210Pb) lead isotopes in 1 year of growth of Sphagnum moss from four ombrotrophic bogs in southern Germany: Geochemical significance and environmental implications

    NASA Astrophysics Data System (ADS)

    Shotyk, William; Kempter, Heike; Krachler, Michael; Zaccone, Claudio

    2015-08-01

    The surfaces of Sphagnum carpets were marked with plastic mesh and 1 year later the production of plant matter was harvested in four ombrotrophic bogs from two regions of southern Germany: Upper Bavaria (Oberbayern, OB) and the Northern Black Forest (Nordschwarzwald, NBF). Radioactive, 210Pb was determined in solid samples using ultralow background gamma spectrometry while total Pb concentrations and stable isotopes (206Pb, 207Pb, 208Pb) were determined in acid digests using ICP-SMS. Up to 12 samples (40 × 40 cm) were collected per site, and 6-10 sites investigated per bog. The greatest variations within a given sampling site were in the range 212-532 Bq kg-1 for 210Pb activity, whereas 206Pb/207Pb and 208Pb/206Pb varied less than 1%. The median values of all parameters for the sites (6-10 per bog) were not significantly different. The median activities of 210Pb (Bq kg-1) in the mosses collected from the bogs in NBF (HO = 372 ± 56, n = 55; WI = 342 ± 58, n = 93) were slightly less from those in OB (GS = 394 ± 50, n = 55; KL = 425 ± 58, n = 24). However, the mosses in the NBF bogs exhibited much greater productivity (187-202 g m-2 a-1) compared to those of OB (71-91 g m-2 a-1), and this has a profound impact on the accumulation rates of 210Pb (Bq m-2 a-1), with the bogs in the NBF yielding fluxes (HO = 73 ± 30; WI = 65 ± 20) which are twice those of OB (GS = 29 ± 11; KL = 40 ± 13). Using the air concentrations of 210Pb measured at Schauinsland (SIL) in the southern Black Forest and average annual precipitation, the atmospheric fluxes of 210Pb at SIL (340 Bq m-2 a-1) exceeds the corresponding values obtained from the mosses by a factor of five, providing the first quantitative estimate of the net retention efficiency of 210Pb by Sphagnum. When the 210Pb activities of all moss samples are combined (n = 227), a significant decrease with increasing plant production rate is observed; in contrast, total Pb concentrations show the opposite trend. The contrasting

  7. Radioactive diagnostic agent

    SciTech Connect

    Shigematsu, A.; Aihara, M.; Matsuda, M.; Suzuki, A.; Tsuya, A.

    1984-02-07

    A radioactive diagnostic agent for renal cortex, adrenal cortex, myocardium, brain stem, spinal nerve, etc., which comprises as an essential component monoiodoacetic acid wherein the iodine atom is radioactive.

  8. Artificial Limbs

    MedlinePlus

    ... you are missing an arm or leg, an artificial limb can sometimes replace it. The device, which is ... activities such as walking, eating, or dressing. Some artificial limbs let you function nearly as well as before.

  9. Artificial Intelligence.

    ERIC Educational Resources Information Center

    Waltz, David L.

    1982-01-01

    Describes kinds of results achieved by computer programs in artificial intelligence. Topics discussed include heuristic searches, artificial intelligence/psychology, planning program, backward chaining, learning (focusing on Winograd's blocks to explore learning strategies), concept learning, constraint propagation, language understanding…

  10. Artificial Intelligence.

    ERIC Educational Resources Information Center

    Information Technology Quarterly, 1985

    1985-01-01

    This issue of "Information Technology Quarterly" is devoted to the theme of "Artificial Intelligence." It contains two major articles: (1) Artificial Intelligence and Law" (D. Peter O'Neill and George D. Wood); (2) "Artificial Intelligence: A Long and Winding Road" (John J. Simon, Jr.). In addition, it contains two sidebars: (1) "Calculating and…

  11. Artificial Intelligence.

    ERIC Educational Resources Information Center

    Information Technology Quarterly, 1985

    1985-01-01

    This issue of "Information Technology Quarterly" is devoted to the theme of "Artificial Intelligence." It contains two major articles: (1) Artificial Intelligence and Law" (D. Peter O'Neill and George D. Wood); (2) "Artificial Intelligence: A Long and Winding Road" (John J. Simon, Jr.). In addition, it contains two sidebars: (1) "Calculating and…

  12. Landscape of two-proton radioactivity.

    PubMed

    Olsen, E; Pfützner, M; Birge, N; Brown, M; Nazarewicz, W; Perhac, A

    2013-05-31

    Ground-state two-proton (2p) radioactivity is a decay mode found in isotopes of elements with even atomic numbers located beyond the two-proton drip line. So far, this exotic process has been experimentally observed in a few light- and medium-mass nuclides with Z≤30. In this study, using state-of-the-art nuclear density functional theory, we globally analyze 2p radioactivity and for the first time identify 2p-decay candidates in elements heavier than strontium. We predict a few cases where the competition between 2p emission and α decay may be observed. In nuclei above lead, the α-decay mode is found to be dominating and no measurable candidates for the 2p radioactivity are expected.

  13. Isotopic ratio of 129I/127I in seaweed measured by neutron activation analysis with gamma-gamma coincidence.

    PubMed

    Toh, Y; Hatsukawa, Y; Oshima, M; Shinohara, N; Hayakawa, T; Kushita, K; Ueno, T

    2002-07-01

    129I is a long-lived (1.6 x 10(7) y) radionuclide that is produced in nature as the result of spontaneous fission of heavy elements and reaction of xenon with cosmic rays. Recently, however, artificial sources from nuclear power plants and nuclear test explosions have become a significant component of environmental radioactive iodine. Coincidence gamma-ray detection using Ge detectors makes it possible to simultaneously resolve the numerous gamma-rays produced by neutron activation. In this study, the coincidence gamma-ray detection technique was combined with neutron activation analysis to determine the radioactive iodine composition of seaweed. The ratio of 129I/127I in this common Japanese food item collected from the Ibaraki prefecture has been derived without the need for radiochemical purification. The isotopic ratio of 129I/127I in Kajime algae is 3.5(5) x 10(-10).

  14. [Henri Beckquerel's discovery of radioactivity, and history of nuclear medicine. 100 years in the shadow or on the shoulder of Röntgen].

    PubMed

    Rootwelt, K

    1996-12-10

    In 1896 Henri Becquerel discovered that uranium emitted penetrating rays similar to X-rays. His finding started a series of discoveries that were rewarded with numerous Nobel prizes. Marie and Pierre Curie found that thorium was radioactive too, and discovered and described two new elements, polonium and radium. They also found that radioactive radiation could be separated into alpha, beta and gamma rays. In 1993 their daughter Irene Joliot-Curie and her husband Frederic Joliot managed to produce radioactivity artificially by bombarding atomic nuclei with alpha particles. Enrico Fermi did likewise, but bombarded the nuclei with neutrons. In the cyclotron invented by Ernest Lawrence, radioactive isotopes were produced by proton bombardment. The ability to produce radioisotopes of different elements initiated a variety of tracer studies in biology and medicine. The number of studies increased exponentially when the nuclear reactor in Oak Ridge, US, was opened for radionuclide production in 1946. This article summarises the history of the application of radionuclides in science and medicine internationally and in Norway until now.

  15. PERSPECTIVE: Fireworks and radioactivity

    NASA Astrophysics Data System (ADS)

    Breitenecker, Katharina

    2009-09-01

    both reaction products and unburnt constituents of a pyrotechnic mixture. One major environmental concern in pyrotechnics focuses on the emission of heavy metals. This is the topic discussed in the article by Georg Steinhauser and Andreas Musilek in this issue [4]. A possible interrelationship between respiratory effects and fireworks emissions of barium-rich aerosols was also raised last year [5]. In recent years the potential hazard of naturally occurring radioactive material has become of importance to the scientific community. Naturally occurring radionuclides can be of terrestrial or cosmological origin. Terrestrial radionuclides were present in the presolar cloud that later contracted in order to build our solar system. These radionuclides—mainly heavy metals—and their non-radioactive isotopes are nowadays fixed in the matrix of the Earth's structure. Usually, their percentage is quite small compared to their respective stable isotopes—though there are exceptions like in the case of radium. The problem with environmental pollution due to naturally occurring radioactive material begins when this material is concentrated due to mining and milling, and later further processed [6]. Environmental pollution due to radioactive material goes back as far as the Copper and Iron Ages, when the first mines were erected in order to mine ores (gold, silver, copper, iron, etc), resulting in naturally occurring radioactive material being set free with other dusts into the atmosphere. So where is the link between pyrotechnics and radioactivity? In this article presented by Georg Steinhauser and Andreas Musilek [4], the pyrotechnic ingredients barium nitrate and strontium nitrate are explored with respect to their chemical similarities to radium. The fundamental question, therefore, was whether radium can be processed together with barium and strontium. If so, the production and ignition of these pyrotechnic ingredients could cause atmospheric pollution with radium aerosols

  16. Radioactivity and food

    SciTech Connect

    Olszyna-Marzys, A.E. )

    1990-03-01

    Two topics relating to radioactivity and food are discussed: food irradiation for preservation purposes, and food contamination from radioactive substances. Food irradiation involves the use of electromagnetic energy (x and gamma rays) emitted by radioactive substances or produced by machine in order to destroy the insects and microorganisms present and prevent germination. The sanitary and economic advantages of treating food in this way are discussed. Numerous studies have confirmed that under strictly controlled conditions no undesirable changes take place in food that has been irradiated nor is radioactivity induced. Reference is made to the accident at the Chernobyl nuclear power station, which aroused public concern about irradiated food. The events surrounding the accident are reviewed, and its consequences with regard to contamination of different foods with radioactive substances, particularly iodine-131 and cesium-137, are described. Also discussed are the steps that have been taken by different international organizations to set limits on acceptable radioactivity in food.15 references.

  17. ORNL radioactive waste operations

    SciTech Connect

    Sease, J.D.; King, E.M.; Coobs, J.H.; Row, T.H.

    1982-01-01

    Since its beginning in 1943, ORNL has generated large amounts of solid, liquid, and gaseous radioactive waste material as a by-product of the basic research and development work carried out at the laboratory. The waste system at ORNL has been continually modified and updated to keep pace with the changing release requirements for radioactive wastes. Major upgrading projects are currently in progress. The operating record of ORNL waste operation has been excellent over many years. Recent surveillance of radioactivity in the Oak Ridge environs indicates that atmospheric concentrations of radioactivity were not significantly different from other areas in East Tennesseee. Concentrations of radioactivity in the Clinch River and in fish collected from the river were less than 4% of the permissible concentration and intake guides for individuals in the offsite environment. While some radioactivity was released to the environment from plant operations, the concentrations in all of the media sampled were well below established standards.

  18. Artificial Intelligence,

    DTIC Science & Technology

    PATTERN RECOGNITION, * ARTIFICIAL INTELLIGENCE , *TEXTBOOKS, COMPUTER PROGRAMMING, MATHEMATICAL LOGIC, ROBOTS, PROBLEM SOLVING, STATISTICAL ANALYSIS, GAME THEORY, NATURAL LANGUAGE, SELF ORGANIZING SYSTEMS.

  19. Comparison of the radioactive and modified techniques for measurement of stream reaeration coefficients

    USGS Publications Warehouse

    Rathbun, R.E.; Grant, R. Stephen

    1978-01-01

    There are advantages and disadvantages to both the radioactive and modified tracer techniques. The main advantage of the radioactive technique is that the tracer gas is chemically inert; the main disadvantage is that a radioactive isotope of the gas must be used to obtain the necessary analytical sensitivity. The main advantage of the modified technique is that radioactive tracers are not necessary; the main disadvantage is that the hydrocarbon tracer gases may be subject to biological degradation and sorption losses. Results of this comparison study suggest that the modified technique is a promising alternative to the use of radioactive tracers.

  20. Radioactive Waste Management Basis

    SciTech Connect

    Perkins, B K

    2009-06-03

    The purpose of this Radioactive Waste Management Basis is to describe the systematic approach for planning, executing, and evaluating the management of radioactive waste at LLNL. The implementation of this document will ensure that waste management activities at LLNL are conducted in compliance with the requirements of DOE Order 435.1, Radioactive Waste Management, and the Implementation Guide for DOE Manual 435.1-1, Radioactive Waste Management Manual. Technical justification is provided where methods for meeting the requirements of DOE Order 435.1 deviate from the DOE Manual 435.1-1 and Implementation Guide.

  1. Methods for determination of radioactive substances in water and fluvial sediments

    USGS Publications Warehouse

    Thatcher, Leland Lincoln; Janzer, Victor J.; Edwards, Kenneth W.

    1977-01-01

    Analytical methods for the determination of some of the more important components of fission or neutron activation product radioactivity and of natural radioactivity found in water are reported. The report for each analytical method includes conditions for application of the method, a summary of the method, interferences, required apparatus and reagents, analytical procedures, calculations, reporting of results, and estimation of precision. The fission product isotopes considered are cesium-137, strontium-90, and ruthenium-106. The natural radioelements and isotopes considered are uranium, lead-210, radium-226, radium-228, tritium, and carbon-14. A gross radioactivity survey method and a uranium isotope ratio method are given. When two analytical methods are in routine use for an individual isotope, both methods are reported with identification of the specific areas of application of each. Techniques for the collection and preservation of water samples to be analyzed for radioactivity are discussed.

  2. Online Catalog of Isotope Products from DOE's National Isotope Development Center

    DOE Data Explorer

    The National Isotope Development Center (NIDC) interfaces with the User Community and manages the coordination of isotope production across the facilities and business operations involved in the production, sale, and distribution of isotopes. A virtual center, the NIDC is funded by the Isotope Development and Production for Research and Applications (IDPRA) subprogram of the Office of Nuclear Physics in the U.S. Department of Energy Office of Science. The Isotope subprogram supports the production, and the development of production techniques of radioactive and stable isotopes that are in short supply for research and applications. Isotopes are high-priority commodities of strategic importance for the Nation and are essential for energy, medical, and national security applications and for basic research; a goal of the program is to make critical isotopes more readily available to meet domestic U.S. needs. This subprogram is steward of the Isotope Production Facility (IPF) at Los Alamos National Laboratory (LANL), the Brookhaven Linear Isotope Producer (BLIP) facility at BNL, and hot cell facilities for processing isotopes at ORNL, BNL and LANL. The subprogram also coordinates and supports isotope production at a suite of university, national laboratory, and commercial accelerator and reactor facilities throughout the Nation to promote a reliable supply of domestic isotopes. The National Isotope Development Center (NIDC) at ORNL coordinates isotope production across the many facilities and manages the business operations of the sale and distribution of isotopes.

  3. Induced radioactivity in LDEF components

    NASA Technical Reports Server (NTRS)

    Harmon, B. A.; Fishman, G. J.; Parnell, T. A.; Laird, C. E.

    1991-01-01

    The systematics of induced radioactivity on the Long Duration Exposure Facility (LDEF) were studied in a wide range of materials using low level background facilities for detection of gamma rays. Approx. 400 samples of materials processed from structural parts of the spacecraft, as well as materials from onboard experiments, were analyzed at national facilities. These measurements show the variety of radioisotopes that are produced with half-lives greater than 2 wks, most of which are characteristic of proton induced reactions above 20 MeV. For the higher activity, long lived isotopes, it was possible to map the depth and directional dependences of the activity. Due to the stabilized configuration of the LDEF, the induced radioactivity data clearly show contributions from the anisotropic trapped proton flux in the South Atlantic Anomaly. This effect is discussed, along with evidence for activation by galactic protons and thermal neutrons. The discovery of Be-7 was made on leading side parts of the spacecraft, although this was though not to be related to the in situ production of radioisotopes from external particle fluxes.

  4. Artificial Intelligence.

    ERIC Educational Resources Information Center

    Thornburg, David D.

    1986-01-01

    Overview of the artificial intelligence (AI) field provides a definition; discusses past research and areas of future research; describes the design, functions, and capabilities of expert systems and the "Turing Test" for machine intelligence; and lists additional sources for information on artificial intelligence. Languages of AI are…

  5. Artificial Intelligence.

    ERIC Educational Resources Information Center

    Smith, Linda C.; And Others

    1988-01-01

    A series of articles focuses on artificial intelligence research and development to enhance information systems and services. Topics discussed include knowledge base designs, expert system development tools, natural language processing, expert systems for reference services, and the role that artificial intelligence concepts should have in…

  6. Artificial Intelligence.

    ERIC Educational Resources Information Center

    Thornburg, David D.

    1986-01-01

    Overview of the artificial intelligence (AI) field provides a definition; discusses past research and areas of future research; describes the design, functions, and capabilities of expert systems and the "Turing Test" for machine intelligence; and lists additional sources for information on artificial intelligence. Languages of AI are…

  7. [Artificial organs].

    PubMed

    Raguin, Thibaut; Dupret-Bories, Agnès; Debry, Christian

    2017-01-01

    Research has been fighting against organ failure and shortage of donations by supplying artificial organs for many years. With the raise of new technologies, tissue engineering and regenerative medicine, many organs can benefit of an artificial equivalent: thanks to retinal implants some blind people can visualize stimuli, an artificial heart can be proposed in case of cardiac failure while awaiting for a heart transplant, artificial larynx enables laryngectomy patients to an almost normal life, while the diabetic can get a glycemic self-regulation controlled by smartphones with an artificial device. Dialysis devices become portable, as well as the oxygenation systems for terminal respiratory failure. Bright prospects are being explored or might emerge in a near future. However, the retrospective assessment of putative side effects is not yet sufficient. Finally, the cost of these new devices is significant even if the advent of three dimensional printers may reduce it. © 2017 médecine/sciences – Inserm.

  8. Artificial blood.

    PubMed

    Sarkar, Suman

    2008-07-01

    Artificial blood is a product made to act as a substitute for red blood cells. While true blood serves many different functions, artificial blood is designed for the sole purpose of transporting oxygen and carbon dioxide throughout the body. Depending on the type of artificial blood, it can be produced in different ways using synthetic production, chemical isolation, or recombinant biochemical technology. Development of the first blood substitutes dates back to the early 1600s, and the search for the ideal blood substitute continues. Various manufacturers have products in clinical trials; however, no truly safe and effective artificial blood product is currently marketed. It is anticipated that when an artificial blood product is available, it will have annual sales of over $7.6 billion in the United States alone.

  9. Isotope shifts and hyperfine structure in polonium isotopes by atomic-beam laser spectroscopy

    NASA Astrophysics Data System (ADS)

    Kowalewska, D.; Bekk, K.; Göring, S.; Hanser, A.; Kälber, W.; Meisel, G.; Rebel, H.

    1991-08-01

    Laser-induced fluorescence spectroscopy in a collimated atomic beam has been applied to determine isotope shifts and the hyperfine structure of an isotopic chain of the radioactive element polonium (200Po, 202Po, 204-210Po). The relative isotope shifts show a striking similarity with results for other elements in the vicinity of Pb, even reproducing details of the odd-even staggering.

  10. Radioactive waste disposal package

    DOEpatents

    Lampe, Robert F.

    1986-01-01

    A radioactive waste disposal package comprising a canister for containing vitrified radioactive waste material and a sealed outer shell encapsulating the canister. A solid block of filler material is supported in said shell and convertible into a liquid state for flow into the space between the canister and outer shell and subsequently hardened to form a solid, impervious layer occupying such space.

  11. A Remote Radioactivity Experiment

    ERIC Educational Resources Information Center

    Jona, Kemi; Vondracek, Mark

    2013-01-01

    Imagine a high school with very few experimental resources and limited budgets that prevent the purchase of even basic laboratory equipment. For example, many high schools do not have the means of experimentally studying radioactivity because they lack Geiger counters and/or good radioactive sources. This was the case at the first high school one…

  12. A Remote Radioactivity Experiment

    ERIC Educational Resources Information Center

    Jona, Kemi; Vondracek, Mark

    2013-01-01

    Imagine a high school with very few experimental resources and limited budgets that prevent the purchase of even basic laboratory equipment. For example, many high schools do not have the means of experimentally studying radioactivity because they lack Geiger counters and/or good radioactive sources. This was the case at the first high school one…

  13. Radioactive waste disposal package

    DOEpatents

    Lampe, Robert F.

    1986-11-04

    A radioactive waste disposal package comprising a canister for containing vitrified radioactive waste material and a sealed outer shell encapsulating the canister. A solid block of filler material is supported in said shell and convertible into a liquid state for flow into the space between the canister and outer shell and subsequently hardened to form a solid, impervious layer occupying such space.

  14. Radioactive Wastes. Revised.

    ERIC Educational Resources Information Center

    Fox, Charles H.

    This publication is one of a series of information booklets for the general public published by the United States Atomic Energy Commission. This booklet deals with the handling, processing and disposal of radioactive wastes. Among the topics discussed are: The Nature of Radioactive Wastes; Waste Management; and Research and Development. There are…

  15. Temporary Personal Radioactivity

    NASA Astrophysics Data System (ADS)

    Myers, Fred

    2012-11-01

    As part of a bone scan procedure to look for the spread of prostate cancer, I was injected with radioactive technetium. In an effort to occupy/distract my mind, I used a Geiger counter to determine if the radioactive count obeyed the inverse-square law as a sensor was moved away from my bladder by incremental distances.

  16. Sampling for Airborne Radioactivity

    DTIC Science & Technology

    2007-10-01

    compared to betas, gammas and neutrons. For an airborne radioactivity detection system, it is most important to be able to detect alpha particles and... Airborne radioactive particles may emit alpha, beta, gamma or neutron radiation, depending on which radioisotope is present. From a health perspective...

  17. Transportation of Radioactive Materials

    DTIC Science & Technology

    1955-07-01

    measurements of radiation must be made with a Landsverk- Wollan Electrometer Model L-100 or equally efficient standardized meter. Acceptable instruments... Wollan Electrometer Model L-100, or equally efficient standardized meter. 40 146.25-25. Exemptions for radioactive materials: (a) Radioactive materials

  18. Isotopic Biogeochemistry

    NASA Technical Reports Server (NTRS)

    Hayes, J. M.

    1985-01-01

    An overview is provided of the biogeochemical research. The funding, productivity, personnel and facilities are reviewed. Some of the technical areas covered are: carbon isotopic records; isotopic studies of banded iron formations; isotope effects in microbial systems; studies of organic compounds in ancient sediments; and development in isotopic geochemistry and analysis.

  19. Isotopic separation

    SciTech Connect

    Chen, C.

    1981-03-10

    Method and apparatus for separating isotopes in an isotopic mixture of atoms or molecules by increasing the mass differential among isotopic species. The mixture containing a particular isotope is selectively irradiated so as to selectively excite the isotope. This preferentially excited species is then reacted rapidly with an additional preselected radiation, an electron or another chemical species so as to form a product containing the specific isotope, but having a mass different than the original species initially containing the particular isotope. The product and the remaining balance of the mixture is then caused to flow through a device which separates the product from the mixture based upon the increased mass differential.

  20. Induced Radioactivity in Recovered Skylab Materials. [gamma ray spectra

    NASA Technical Reports Server (NTRS)

    Fishman, G. J.; Meegan, C. A.

    1980-01-01

    Four radioactive isotopes found in aluminum and stainless steel samples from Skylab debris were recovered in Australia. The low-level activity was induced by high-energy protons and neutrons in the space environment. Measurements of the specific activities are given.

  1. Search for and analysis of radioactive halos in lunar material

    NASA Technical Reports Server (NTRS)

    Gentry, R. V.

    1976-01-01

    The lunar halo search was conducted because halos in terrestrial minerals serve as pointers to localized radioactivity, and make possible analytical studies on the problems of isotopic dating and mode of crystallization of the host mineral. Ancillary studies were conducted on terrestrial halos and on certain samples of special origin such as tektites and meteorites.

  2. Accelerated radioactive nuclear beams: Existing and planned facilities

    SciTech Connect

    Nitschke, J.M.

    1992-07-01

    An over-view of existing and planned radioactive nuclear beam facilities world-wide. Two types of production methods are distinguished: projectile fragmentation and the on-line isotope separator (ISOL) method. While most of the projectile fragmentation facilities are already in operation, almost all the ISOL-based facilities are in still the planning stage.

  3. Radioactivity in fossils at the Hagerman Fossil Beds National Monument.

    PubMed

    Farmer, C Neal; Kathren, Ronald L; Christensen, Craig

    2008-08-01

    Since 1996, higher than background levels of naturally occurring radioactivity have been documented in both fossil and mineral deposits at Hagerman Fossil Beds National Monument in south-central Idaho. Radioactive fossil sites occur primarily within an elevation zone of 900-1000 m above sea level and are most commonly found associated with ancient river channels filled with sand. Fossils found in clay rich deposits do not exhibit discernable levels of radioactivity. Out of 300 randomly selected fossils, approximately three-fourths exhibit detectable levels of natural radioactivity ranging from 1 to 2 orders of magnitude above ambient background levels when surveyed with a portable hand held Geiger-Muller survey instrument. Mineral deposits in geologic strata also show above ambient background levels of radioactivity. Radiochemical lab analysis has documented the presence of numerous natural radioactive isotopes. It is postulated that ancient groundwater transported radioactive elements through sand bodies containing fossils which precipitated out of solution during the fossilization process. The elevated levels of natural radioactivity in fossils may require special precautions to ensure that exposures to personnel from stored or displayed items are kept as low as reasonably achievable (ALARA).

  4. A Remote Radioactivity Experiment

    NASA Astrophysics Data System (ADS)

    Jona, Kemi; Vondracek, Mark

    2013-01-01

    Imagine a high school with very few experimental resources and limited budgets that prevent the purchase of even basic laboratory equipment. For example, many high schools do not have the means of experimentally studying radioactivity because they lack Geiger counters and/or good radioactive sources. This was the case at the first high school one of us (MV) worked at, and after talking with numerous colleagues we know this is still the case at many schools. What options are there then for physics teachers to allow their students to experimentally investigate certain characteristics of radioactivity, such as how distance affects the intensity of radiation coming from a radioactive source? There are computer simulations that can be run, or perhaps the teacher has a light sensor and tries to make an analogy between the intensity of light from a light bulb and the intensity of radiation from a radioactive source based on geometric arguments to get an inverse-square law. But for many there is no direct experimental option if one does not possess a Geiger counter and good radioactive sample. It is for that teacher and class of students that an online, remote radioactivity experiment was created.

  5. Multicomponent and multistep radioactive decay modeling module for groundwater flow and contaminant transport computer code

    NASA Astrophysics Data System (ADS)

    Kharkhordin, I. L.

    2013-12-01

    Correct calculations of multistep radioactive decay is important for radionuclide transport forecast at contaminated sites and designing radionuclide storage facilities as well as for a number applications of natural radioactive tracers for understanding of groundwater flow in complex hydrogeological systems. Radioactive chains can involves a number of branches with certain probabilities of decay and up to fourteen steps. General description of radioactive decay in complex system could be presented as a system of linear differential equations. Numerical solution of this system encounters a difficulties connected with wide rage of radioactive decay constants variations. In present work the database with 1253 records of radioactive isotope decay parameters for 97 elements was created. An algorithm of analytical solution construction and solving was elaborated for arbitrary radioactive isotope system taking into account the possible chain branching and connection. The algorithm is based on radionuclide decay graphs. The main steps of algorithm is as follows: a) searching of all possible isotopes in database, creation full isotope list; b) looking for main parent isotopes; c) construction of all possible radioactive chains; d) looking for branching and connections in decay chains, marking of links as primary (left chain in graph for main parent isotope), secondary (after connection), and recurring (before branching); e) construction and calculation the coefficients for analytical solutions. The developed computer code was tested on a few simple systems like follows: Cs-135 - one step decay, Sr-90 (Y-90) - two steps decay, U-238+U-235 mixture - complex decay with branching. Calculation of radiogenic He-4 is also possible witch could be important application for groundwater flow and transport model calibration using natural tracers. The computer code for multistep radioactive calculation was elaborated for incorporation into NIMFA code. NIMFA is a parallel computer code

  6. Nuclide radioactive decay data uncertainties library

    NASA Astrophysics Data System (ADS)

    Barabanova, D. S.; Zherdev, G. M.

    2017-01-01

    The results of the developing the library of uncertainties of radioactive decay data in the ABBN data library format are described. Different evaluations of uncertainties were compared and their effects on the results of calculations of residual energy release were determined using the test problems and experiment. Tables were generated in the ABBN format with the data obtained on the basis of libraries in ENDF-6 format. 3821 isotopes from the ENDF/B-7 data library, 3852 isotopes from the JEFF-3.11 data library and 1264 isotopes from the JENDL-4.0 data library were processed. It was revealed that the differences in the evaluations accepted in different decay data libraries are not so big, although they sometimes exceed the uncertainties assigned to the data in the ENDF/B-7 and JEFF-3.11 libraries, which as a rule, they agree with each other. On the basis of developed method it is supposed to create a library of data uncertainties for radioactive decay within the constant data system in FSUE RFNC-VNIIEF with its further connection with CRYSTAL module.

  7. Helium isotopic abundance variation in nature

    SciTech Connect

    Holden, N.E.

    1993-08-01

    The isotopic abundance of helium in nature has been reviewed. This atomic weight value is based on the value of helium in the atmosphere, which is invariant around the world and up to a distance of 100,000 feet. Helium does vary in natural gas, volcanic rocks and gases, ocean floor sediments, waters of various types and in radioactive minerals and ores due to {alpha} particle decay of radioactive nuclides.

  8. ELECTRONIC ANALOG COMPUTER FOR DETERMINING RADIOACTIVE DISINTEGRATION

    DOEpatents

    Robinson, H.P.

    1959-07-14

    A computer is presented for determining growth and decay curves for elements in a radioactive disintegration series wherein one unstable element decays to form a second unstable element or isotope, which in turn forms a third element, etc. The growth and decay curves of radioactive elements are simulated by the charge and discharge curves of a resistance-capacitance network. Several such networks having readily adjustable values are connected in series with an amplifier between each successive pair. The time constant of each of the various networks is set proportional to the half-life of a corresponding element in the series represented and the charge and discharge curves of each of the networks simulates the element growth and decay curve.

  9. Temporary Personal Radioactivity

    ERIC Educational Resources Information Center

    Myers, Fred

    2012-01-01

    As part of a bone scan procedure to look for the spread of prostate cancer, I was injected with radioactive technetium. In an effort to occupy/distract my mind, I used a Geiger counter to determine if the radioactive count obeyed the inverse-square law as a sensor was moved away from my bladder by incremental distances. (Contains 1 table and 2…

  10. Temporary Personal Radioactivity

    ERIC Educational Resources Information Center

    Myers, Fred

    2012-01-01

    As part of a bone scan procedure to look for the spread of prostate cancer, I was injected with radioactive technetium. In an effort to occupy/distract my mind, I used a Geiger counter to determine if the radioactive count obeyed the inverse-square law as a sensor was moved away from my bladder by incremental distances. (Contains 1 table and 2…

  11. Container for radioactive materials

    DOEpatents

    Fields, Stanley R.

    1985-01-01

    A container for housing a plurality of canister assemblies containing radioactive material and disposed in a longitudinally spaced relation within a carrier to form a payload package concentrically mounted within the container. The payload package includes a spacer for each canister assembly, said spacer comprising a base member longitudinally spacing adjacent canister assemblies from each other and a sleeve surrounding the associated canister assembly for centering the same and conducting heat from the radioactive material in a desired flow path.

  12. Radioactive gold ring dermatitis

    SciTech Connect

    Miller, R.A.; Aldrich, J.E. )

    1990-08-01

    A superficial squamous cell carcinoma developed in a woman who wore a radioactive gold ring for more than 30 years. Only part of the ring was radioactive. Radiation dose measurements indicated that the dose to basal skin layer was 2.4 Gy (240 rad) per week. If it is assumed that the woman continually wore her wedding ring for 37 years since purchase, she would have received a maximum dose of approximately 4600 Gy.

  13. Undiagnosed illnesses and radioactive warfare.

    PubMed

    Duraković, Asaf

    2003-10-01

    The internal contamination with depleted uranium (DU) isotopes was detected in British, Canadian, and United States Gulf War veterans as late as nine years after inhalational exposure to radioactive dust in the Persian Gulf War I. DU isotopes were also identified in a Canadian veteran's autopsy samples of lung, liver, kidney, and bone. In soil samples from Kosovo, hundreds of particles, mostly less than 5 microm in size, were found in milligram quantities. Gulf War I in 1991 resulted in 350 metric tons of DU deposited in the environment and 3-6 million grams of DU aerosol released into the atmosphere. Its legacy, Gulf War disease, is a complex, progressive, incapacitating multiorgan system disorder. The symptoms include incapacitating fatigue, musculoskeletel and joint pains, headaches, neuropsychiatric disorders, affect changes, confusion, visual problems, changes of gait, loss of memory, lymphadenopathies, respiratory impairment, impotence, and urinary tract morphological and functional alterations. Current understanding of its etiology seems far from being adequate. After the Afghanistan Operation Anaconda (2002), our team studied the population of Jalalabad, Spin Gar, Tora Bora, and Kabul areas, and identified civilians with the symptoms similar to those of Gulf War syndrome. Twenty-four-hour urine samples from 8 symptomatic subjects were collected by the following criteria: 1) the onset of symptoms relative to the bombing raids; 2) physical presence in the area of the bombing; and 3) clinical manifestations. Control subjects were selected among the sympotom-free residents in non-targeted areas. All samples were analyzed for the concentration and ratio of four uranium isotopes, (234)U, (235)U, (236)U and (238)U, by using a multicollector, inductively coupled plasma ionization mass spectrometry. The first results from the Jalalabad province revealed urinary excretion of total uranium in all subjects significantly exceeding the values in the nonexposed population

  14. Hydrocolloid-stabilized magnetite for efficient removal of radioactive phosphates.

    PubMed

    Vellora Thekkae Padil, Vinod; Rouha, Michael; Cerník, Miroslav

    2014-01-01

    Liquid radioactive waste is a common by-product when using radioactive isotopes in research and medicine. Efficient remediation of such liquid waste is crucial for increasing safety during the necessary storage of the material. Herein, we present a novel Gum Karaya stabilized magnetite for the efficient removal of radioactive phosphorus (32)P from liquid radioactive waste. This environmentally friendly material is well suited to be used as a nanohydrogel for the removal of liquid waste, which can then be stored in a smaller space and without the risk of the spills inherent to the initial liquid material. The maximum adsorption capacity of the GK/M in this study was found to be 15.68 GBq/g. We present a thorough morphological characterization of the synthesised GK/M, as well as a discussion of the possible phosphorus adsorption mechanisms.

  15. Hydrocolloid-Stabilized Magnetite for Efficient Removal of Radioactive Phosphates

    PubMed Central

    Vellora Thekkae Padil, Vinod; Rouha, Michael; Černík, Miroslav

    2014-01-01

    Liquid radioactive waste is a common by-product when using radioactive isotopes in research and medicine. Efficient remediation of such liquid waste is crucial for increasing safety during the necessary storage of the material. Herein, we present a novel Gum Karaya stabilized magnetite for the efficient removal of radioactive phosphorus 32P from liquid radioactive waste. This environmentally friendly material is well suited to be used as a nanohydrogel for the removal of liquid waste, which can then be stored in a smaller space and without the risk of the spills inherent to the initial liquid material. The maximum adsorption capacity of the GK/M in this study was found to be 15.68 GBq/g. We present a thorough morphological characterization of the synthesised GK/M, as well as a discussion of the possible phosphorus adsorption mechanisms. PMID:24696854

  16. Radioactive material shipping for academic and medical facilities.

    PubMed

    Vernig, Peter G; Tipping, Tracy N; Herrold, Jim; Ward, Paul

    2011-11-01

    This paper is intended as an aid for preparing radioactive material shipments in academic and medical facilities. These facilities may only ship radioactive materials infrequently. As such, ensuring compliance with applicable regulations can be very time consuming. Excepted package shipments (including empty packages) and shipments using Type A packages for a select list of isotopes commonly used by academic and medical facilities are covered. Tables and flowcharts are used to direct one through the process of determining if the material to be shipped meets the definition of radioactive material for transportation purposes and if it qualifies for excepted package or Type A package shipment. The reader is then directed to procedures to properly prepare, document, and ship the radioactive material package.

  17. Making radioactive ion beams - Detecting reaction products

    NASA Astrophysics Data System (ADS)

    Raabe, Riccardo

    2016-10-01

    We present a didactical overview of the methods for the production of radioactive ion beams (RIBs), discussing the main characteristics and associated advantages and drawbacks of the in-flight separation and isotope separation on-line methods. We include a short overview of present and planned facilities, focusing on Europe. In the second part of the paper a brief introduction on the detection of radiation is given, followed by a discussion of the specific problems related to radiation detection in measurements involving RIBs. A few illustrative examples of detection setups are presented.

  18. Radioactive waste disposal via electric propulsion

    NASA Technical Reports Server (NTRS)

    Burns, R. E.

    1975-01-01

    It is shown that space transportation is a feasible method of removal of radioactive wastes from the biosphere. The high decay heat of the isotopes powers a thermionic generator which provides electrical power for ion thrust engines. The massive shields (used to protect ground and flight personnel) are removed in orbit for subsequent reuse; the metallic fuel provides a shield for the avionics that guides the orbital stage to solar system escape. Performance calculations indicate that 4000 kg. of actinides may be removed per Shuttle flight. Subsidiary problems - such as cooling during ascent - are discussed.

  19. Radioactive waste disposal via electric propulsion

    NASA Technical Reports Server (NTRS)

    Burns, R. E.

    1975-01-01

    It is shown that space transportation is a feasible method of removal of radioactive wastes from the biosphere. The high decay heat of the isotopes powers a thermionic generator which provides electrical power for ion thrust engines. The massive shields (used to protect ground and flight personnel) are removed in orbit for subsequent reuse; the metallic fuel provides a shield for the avionics that guides the orbital stage to solar system escape. Performance calculations indicate that 4000 kg. of actinides may be removed per Shuttle flight. Subsidiary problems - such as cooling during ascent - are discussed.

  20. The use of artificial neural networks in PVT-based radiation portal monitors

    SciTech Connect

    Kangas, Lars J.; Keller, Paul E.; Siciliano, Edward R.; Kouzes, Richard T.; Ely, James H.

    2008-03-21

    Polyvinyl toluene (PVT) based gamma-ray scintillation detectors are cost effective for use in radiation portal monitors (RPMs) applied to screening for illicit radioactive materials at international border crossings. While PVT detectors provide good sensitivity in detecting the presence of radioactive materials, they provide poor spectral resolution, limiting their ability to identify the isotopic content of the source of radiation. Thus using only total-spectrum or gross-count alarm algorithms, PVT-based RPMs cannot distinguish innocent materials that contain low-levels of normally occurring radioactivity from special nuclear materials of concern. To reduce the number of “nuisance” alarms produced in PVT-based RPMs by innocent materials, algorithms that analyze spectra from PVT detectors must be optimized to make use of the limited information contained in their energy spectra. This paper discusses how artificial neural networks (ANNs) can be used in such an analysis. The objective was to reduce the nuisance/false alarm probability while maintaining high detection probabilities, thus allowing gross count alarm thresholds to be raised without loss of performance and sensitivity to radioactive materials of interest. The spectra used in this study were obtained from actual PVT-based RPM data, and included cases where simulated spectra were inserted into the measured spectra. This paper also includes an analysis of spectral channel importance and shows evaluations of two methods used to rebin energy spectra into smaller sets. The results show that ANNs can be used with RPMs to reduce nuisance alarms. The algorithms described can be used in analyzing PVT spectra, and potentially sodium iodide spectra.

  1. Compelling Research Opportunities using Isotopes

    SciTech Connect

    2009-04-23

    Isotopes are vital to the science and technology base of the US economy. Isotopes, both stable and radioactive, are essential tools in the growing science, technology, engineering, and health enterprises of the 21st century. The scientific discoveries and associated advances made as a result of the availability of isotopes today span widely from medicine to biology, physics, chemistry, and a broad range of applications in environmental and material sciences. Isotope issues have become crucial aspects of homeland security. Isotopes are utilized in new resource development, in energy from bio-fuels, petrochemical and nuclear fuels, in drug discovery, health care therapies and diagnostics, in nutrition, in agriculture, and in many other areas. The development and production of isotope products unavailable or difficult to get commercially have been most recently the responsibility of the Department of Energy's Nuclear Energy program. The President's FY09 Budget request proposed the transfer of the Isotope Production program to the Department of Energy's Office of Science in Nuclear Physics and to rename it the National Isotope Production and Application program (NIPA). The transfer has now taken place with the signing of the 2009 appropriations bill. In preparation for this, the Nuclear Science Advisory Committee (NSAC) was requested to establish a standing subcommittee, the NSAC Isotope Subcommittee (NSACI), to advise the DOE Office of Nuclear Physics. The request came in the form of two charges: one, on setting research priorities in the short term for the most compelling opportunities from the vast array of disciplines that develop and use isotopes and two, on making a long term strategic plan for the NIPA program. This is the final report to address charge 1. NSACI membership is comprised of experts from the diverse research communities, industry, production, and homeland security. NSACI discussed research opportunities divided into three areas: (1) medicine

  2. The development of radioactive sample surrogates for training and exercises

    SciTech Connect

    Martha Finck; Bevin Brush; Dick Jansen; David Chamberlain; Don Dry; George Brooks; Margaret Goldberg

    2012-03-01

    The development of radioactive sample surrogates for training and exercises Source term information is required for to reconstruct a device used in a dispersed radiological dispersal device. Simulating a radioactive environment to train and exercise sampling and sample characterization methods with suitable sample materials is a continued challenge. The Idaho National Laboratory has developed and permitted a Radioactive Response Training Range (RRTR), an 800 acre test range that is approved for open air dispersal of activated KBr, for training first responders in the entry and exit from radioactively contaminated areas, and testing protocols for environmental sampling and field characterization. Members from the Department of Defense, Law Enforcement, and the Department of Energy participated in the first contamination exercise that was conducted at the RRTR in the July 2011. The range was contaminated using a short lived radioactive Br-82 isotope (activated KBr). Soil samples contaminated with KBr (dispersed as a solution) and glass particles containing activated potassium bromide that emulated dispersed radioactive materials (such as ceramic-based sealed source materials) were collected to assess environmental sampling and characterization techniques. This presentation summarizes the performance of a radioactive materials surrogate for use as a training aide for nuclear forensics.

  3. Stable Isotope Signatures for Microbial Forensics

    SciTech Connect

    Kreuzer, Helen W.

    2012-01-03

    The isotopic distribution of the atoms composing the molecules of microorganisms is a function of the substrates used by the organisms. The stable isotope content of an organism is fixed so long as no further substrate consumption and biosynthesis occurs, while the radioactive isotopic content decays over time. The distribution of stable isotopes of C, N, O and H in heterotrophic microorganisms is a direct function of the culture medium, and therefore the stable isotope composition can be used to associate samples with potential culture media and also with one another. The 14C content depends upon the 14C content, and therefore the age, of the organic components of the culture medium, as well as on the age of the culture itself. Stable isotope signatures can thus be used for sample matching, to associate cultures with specific growth media, and to predict characteristics of growth media.

  4. (Availability of isotopic materials)

    SciTech Connect

    Adair, H.L.

    1987-10-22

    The traveler visited several installations in Belgium, Germany, and England to meet with users of the enriched stable and radioactive materials provided by the ORNL Isotope Distribution Program (IDP). The purpose of the visits was to determine their future needs for the materials and services provided by the ORNL program and to update our existing or potential future customers on the materials and services presently available from the program. In Belgium and England, extreme interest was expressed among our customers and competitors about the status of the High Flux Isotope Reactor (HFIR) at ORNL. This related mainly to our ability to supply the radioisotopes Ir-192 and Gd-153. A number of concerns were expressed about our ability to provide various stable and radioactive materials. Particular concern was expressed about our present capability to supply enriched Kr-85. The traveler participated in an International Atomic Energy Agency (IAEA) specialists' meeting where the chief topic of discussion was the influence of target and sample properties on nuclear data measurements. At the end of this meeting, plans were formalized for a joint IAEA/International Nuclear Target Development Society (INTDS) meeting on sample fabrication and characterization to be held in Darmstadt, Federal Republic of Germany, in 1988. as President, the traveler conducted the 1987 INTDS Board meeting at the Central Bureau of Nuclear Measurements (CBNM). The major agenda items included the recent changes in the INTDS bylaws, guidelines for future hosts of INTDS meetings, and future directions the Society should take.

  5. Radioactivity in food crops

    SciTech Connect

    Drury, J.S.; Baldauf, M.F.; Daniel, E.W.; Fore, C.S.; Uziel, M.S.

    1983-05-01

    Published levels of radioactivity in food crops from 21 countries and 4 island chains of Oceania are listed. The tabulation includes more than 3000 examples of 100 different crops. Data are arranged alphabetically by food crop and geographical origin. The sampling date, nuclide measured, mean radioactivity, range of radioactivities, sample basis, number of samples analyzed, and bibliographic citation are given for each entry, when available. Analyses were reported most frequently for /sup 137/Cs, /sup 40/K, /sup 90/Sr, /sup 226/Ra, /sup 228/Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for /sup 241/Am, /sup 7/Be, /sup 60/Co, /sup 55/Fe, /sup 3/H, /sup 131/I, /sup 54/Mn, /sup 95/Nb, /sup 210/Pb, /sup 210/Po, /sup 106/Ru, /sup 125/Sb, /sup 228/Th, /sup 232/Th, and /sup 95/Zr. Based on the reported data it appears that radioactivity from alpha emitters in food crops is usually low, on the order of 0.1 Bq.g/sup -1/ (wet weight) or less. Reported values of beta radiation in a given crop generally appear to be several orders of magnitude greater than those of alpha emitters. The most striking aspect of the data is the great range of radioactivity reported for a given nuclide in similar food crops with different geographical origins.

  6. Radioactivity in the environment

    SciTech Connect

    Nagel, D.J.; Edson, R.

    1995-12-01

    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.

  7. Artificial Intelligence.

    ERIC Educational Resources Information Center

    Wash, Darrel Patrick

    1989-01-01

    Making a machine seem intelligent is not easy. As a consequence, demand has been rising for computer professionals skilled in artificial intelligence and is likely to continue to go up. These workers develop expert systems and solve the mysteries of machine vision, natural language processing, and neural networks. (Editor)

  8. Nuclear Structure Studies with Stable and Radioactive Beams: The SPES radioactive ion beam project

    NASA Astrophysics Data System (ADS)

    de Angelis, G.; SPES Collaboration; Prete, G.; Andrighetto, A.; Manzolaro, M.; Corradetti, S.; Scarpa, D.; Rossignoli, M.; Monetti, A.; Lollo, M.; Calderolla, M.; Vasquez, J.; Zafiropoulos, D.; Sarchiapone, L.; Benini, D.; Favaron, P.; Rigato, M.; Pegoraro, R.; Maniero, D.; Calabretta, L.; Comunian, M.; Maggiore, M.; Lombardi, A.; Piazza, L.; Porcellato, A. M.; Roncolato, C.; Bisoffi, G.; Pisent, A.; Galatà, A.; Giacchini, M.; Bassato, G.; Canella, S.; Gramegna, F.; Valiente, J.; Bermudez, J.; Mastinu, P. F.; Esposito, J.; Wyss, J.; Russo, A.; Zanella, S.

    2015-04-01

    A new Radioactive Ion Beam (RIB) facility (SPES) is presently under construction at the Legnaro National Laboratories of INFN. The SPES facility is based on the ISOL method using an UCx Direct Target able to sustain a power of 10 kW. The primary proton beam is provided by a high current Cyclotron accelerator with energy of 35-70 MeV and a beam current of 0.2-0.5 mA. Neutron-rich radioactive ions are produced by proton induced fission on an Uranium target at an expected fission rate of the order of 1013 fissions per second. After ionization and selection the exotic isotopes are re-accelerated by the ALPI superconducting LINAC at energies of 10A MeV for masses in the region A=130 amu. The expected secondary beam rates are of the order of 107 - 109 pps. Aim of the SPES facility is to deliver high intensity radioactive ion beams of neutron rich nuclei for nuclear physics research as well as to be an interdisciplinary research centre for radio-isotopes production for medicine and for neutron beams.

  9. Understanding the Radioactive Ingrowth and Decay of Naturally Occurring Radioactive Materials in the Environment: An Analysis of Produced Fluids from the Marcellus Shale.

    PubMed

    Nelson, Andrew W; Eitrheim, Eric S; Knight, Andrew W; May, Dustin; Mehrhoff, Marinea A; Shannon, Robert; Litman, Robert; Burnett, William C; Forbes, Tori Z; Schultz, Michael K

    2015-07-01

    The economic value of unconventional natural gas resources has stimulated rapid globalization of horizontal drilling and hydraulic fracturing. However, natural radioactivity found in the large volumes of "produced fluids" generated by these technologies is emerging as an international environmental health concern. Current assessments of the radioactivity concentration in liquid wastes focus on a single element-radium. However, the use of radium alone to predict radioactivity concentrations can greatly underestimate total levels. We investigated the contribution to radioactivity concentrations from naturally occurring radioactive materials (NORM), including uranium, thorium, actinium, radium, lead, bismuth, and polonium isotopes, to the total radioactivity of hydraulic fracturing wastes. For this study we used established methods and developed new methods designed to quantitate NORM of public health concern that may be enriched in complex brines from hydraulic fracturing wastes. Specifically, we examined the use of high-purity germanium gamma spectrometry and isotope dilution alpha spectrometry to quantitate NORM. We observed that radium decay products were initially absent from produced fluids due to differences in solubility. However, in systems closed to the release of gaseous radon, our model predicted that decay products will begin to ingrow immediately and (under these closed-system conditions) can contribute to an increase in the total radioactivity for more than 100 years. Accurate predictions of radioactivity concentrations are critical for estimating doses to potentially exposed individuals and the surrounding environment. These predictions must include an understanding of the geochemistry, decay properties, and ingrowth kinetics of radium and its decay product radionuclides.

  10. Method for making radioactive metal articles having small dimensions

    DOEpatents

    Ohriner, Evan K.

    2000-01-01

    A method for making a radioactive article such as wire, includes the steps of providing a metal article having a first shape, such a cylinder, that is either radioactive itself or can be converted to a second, radioactive isotope by irradiation; melting the metal article one or more times; optionally adding an alloying metal to the molten metal in order to enhance ductility or other properties; placing the metal article having the first shape (e.g., cylindrical) into a cavity in the interior of an extrusion body (e.g., a cylinder having a cylindrical cavity therein); extruding the extrusion body and the article having the first shape located in the cavity therein, resulting in an elongated extrusion body and an article having a second shape; removing the elongated extrusion body, for example by chemical means, leaving the elongated inner article substantially intact; optionally repeating the extrusion procedure one or more times; and then drawing the elongated article to still further elongate it, into wire, foil, or another desired shape. If the starting metal is enriched in a radioactive isotope or a precursor thereof, the end product can provide a more intense radiation source than conventionally manufactured radioactive wire, foil, or the like.

  11. Radioactive Waste Management

    SciTech Connect

    Bales, J.D.; Graham, J.; Boshears, R.

    1996-01-01

    Radioactive Waste Management (RWM) announces on a monthly basis the current worldwide information available on the critical topics of spent-fuel transport and storage, radioactive effluents from nuclear facilities, techniques of processing radioactive wastes, their storage, and ultimate disposal. Information on remedial actions and other environmental aspects is also included. This publication contains the abstracts of DOE reports, journal articles, conference papers, patents, theses, and monographs added to the Energy Science and Technology Database during the past month. Also included are other US information obtained through acquisition programs or interagency agreements and international information obtained through the International Energy Agency`s Energy Technology Data Exchange, the International Atomic Energy Agency`s International Nuclear Information System or government-to-government agreements.

  12. Radioactive mixed waste disposal

    SciTech Connect

    Jasen, W.G.; Erpenbeck, E.G.

    1993-02-01

    Various types of waste have been generated during the 50-year history of the Hanford Site. Regulatory changes in the last 20 years have provided the emphasis for better management of these wastes. Interpretations of the Atomic Energy Act of 1954 (AEA), the Resource Conservation and Recovery Act of 1976 (RCRA), and the Hazardous and Solid Waste Amendments (HSWA) have led to the definition of radioactive mixed wastes (RMW). The radioactive and hazardous properties of these wastes have resulted in the initiation of special projects for the management of these wastes. Other solid wastes at the Hanford Site include low-level wastes, transuranic (TRU), and nonradioactive hazardous wastes. This paper describes a system for the treatment, storage, and disposal (TSD) of solid radioactive waste.

  13. Container for radioactive materials

    DOEpatents

    Fields, S.R.

    1984-05-30

    A container is claimed for housing a plurality of canister assemblies containing radioactive material. The several canister assemblies are stacked in a longitudinally spaced relation within a carrier to form a payload concentrically mounted within the container. The payload package includes a spacer for each canister assembly, said spacer comprising a base member longitudinally spacing adjacent canister assemblies from each other and sleeve surrounding the associated canister assembly for centering the same and conducting heat from the radioactive material in a desired flow path. 7 figures.

  14. Utilization of coal fly ash in solidification of liquid radioactive waste from research reactor.

    PubMed

    Osmanlioglu, Ahmet Erdal

    2014-05-01

    In this study, the potential utilization of fly ash was investigated as an additive in solidification process of radioactive waste sludge from research reactor. Coal formations include various percentages of natural radioactive elements; therefore, coal fly ash includes various levels of radioactivity. For this reason, fly ashes have to be evaluated for potential environmental implications in case of further usage in any construction material. But for use in solidification of radioactive sludge, the radiological effects of fly ash are in the range of radioactive waste management limits. The results show that fly ash has a strong fixing capacity for radioactive isotopes. Specimens with addition of 5-15% fly ash to concrete was observed to be sufficient to achieve the target compressive strength of 20 MPa required for near-surface disposal. An optimum mixture comprising 15% fly ash, 35% cement, and 50% radioactive waste sludge could provide the solidification required for long-term storage and disposal. The codisposal of radioactive fly ash with radioactive sludge by solidification decreases the usage of cement in solidification process. By this method, radioactive fly ash can become a valuable additive instead of industrial waste. This study supports the utilization of fly ash in industry and the solidification of radioactive waste in the nuclear industry.

  15. Isotopic Changes During Digestion: Protein

    NASA Astrophysics Data System (ADS)

    Tuross, N.

    2013-12-01

    Nutrient and hydrological inputs traverse a complicated route of pH, enzymatic and cellular processes in digestion in higher animals. The end products of digestion are the starting products for biosynthesis that are often used to interpret past life-ways. Using an artificial gut system, the isotopic changes (dD, d18O, d13C and d15N) of protein are documented. Three separate protein sources are subjected to the conditions, chemical and enzymatic, found in the stomach and upper small intestine with only a small shift in the oxygen isotopic composition of the proteins observed. Middle to lower small intestine parameters produced both greater isotopic effects and significantly lower molecular weight products. The role of the gastric enterocyte and the likely involvement of the internal milieu of this cell in the isotopic composition of amino acids that are transported to the liver are reported.

  16. Radioactive nanoparticles and their main applications: recent advances.

    PubMed

    Kharisov, Boris I; Kharissova, Oxana V; Berdonosov, Sergei S

    2014-01-01

    Selected nanoparticles and nanocomposites on the basis of radioactive elements are reviewed. Isotopes of metallic gold, iodine and technetium salts, CeO2 and other lanthanide and actinide compounds, as well as several p- (P, C, F, Te) and d- (Fe, Co, Cu, Cd, Zn) elements form most common radioactive nanoparticles. Methods for their fabrication, including dopation with radionuclides and neutron/proton/deuteron activation, are discussed. These nanocomposites possess a series of useful applications, in particular in biology and medicine, including cancer therapeutics, drug delivery systems and radiotracers, as well as in the studies of several catalytic processes and materials structure.

  17. 2p radioactivity studied by tracking technique

    SciTech Connect

    Mukha, Ivan

    2010-06-01

    The recent advance in experimental studies of short-lived exotic nuclei beyond the proton drip line is presented. In particular, in-flight decays of proton-unbound nuclei with picosecond lifetimes can be probed by a novel technique which tracks all decay products precisely, and the decay vertices as well as the angular correlations of the fragments are deduced from the measured trajectories. The corresponding pioneering experiment which identified a previously-unknown isotope {sup 19}Mg and its two-proton (2p) radioactivity as well as studied the reference 2p decay of the known isotope {sup 16}Ne is described. Systematic studies of other 2p precursors beyond the proton drip line are foreseen with this powerful technique whose sensitivity is larger by factor of 30 in comparison with a conventional invariant-mass method. The 2p radioactivity candidates {sup 30}Ar, {sup 34}Ca and {sup 26}S are discussed. Information about the respective one-proton unbound nuclei can be obtained with this technique by evaluating proton-heavy-fragment correlations. Systematic studies of nuclei beyond the proton drip line, e.g., the well-known proton resonances above the 'waiting points' in the astrophysical rp-process, {sup 69}Br and {sup 73}Br are feasible.

  18. DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS

    SciTech Connect

    NA

    2004-11-22

    The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this modeling activity is to predict dissolved concentrations or solubility limits for 14 elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) important to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are in the form of tabulated functions with pH and log (line integral) CO{sub 2} as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. The output data from this report are fundamental inputs for Total System Performance Assessment for the License Application (TSPA-LA) to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for all of the actinides. These models cover broad ranges of environmental conditions so that they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or otherwise addressed.

  19. Artificial ribonucleases.

    PubMed

    Morrow, J R

    1994-01-01

    Many inorganic and organic compounds promote the reactions catalyzed by RNase A. Both the transesterification step, where a 2',3'-cyclic phosphate is formed with concomitant cleavage of RNA, and the hydrolysis step, where the 2',3'-cyclic phosphate is converted to a phosphate monoester, may be mimicked with compounds that are readily synthesized in the laboratory. Electrophilic activation of the phosphate ester and charge neutralization are generally important means by which artificial RNases promote phosphate diester displacement reactions. Several artificial RNases operate by a bifunctional general acid/general base mechanism, as does RNase A. Provision of an intramolecular nucleophile appears to be an important pathway for metal complex promoted phosphate diester hydrolysis. In contrast to the successful design of compounds that promote the reactions catalyzed by RNase A, there are no artificial nucleases to date that will cleave the 3' P-O bond of RNA or hydrolyze an oligonucleotide of DNA. Artificial RNases based on both metal complexes and organic compounds have been described. Metal complexes may be particularly effective catalysts for both transesterification and hydrolysis reactions of phosphate diesters. Under physiological conditions (37 degrees C and neutral pH), several metal complexes catalyze the transesterification of RNA. Future work should involve the development of metal complexes which are inert to metal ion release but which maintain open coordination sites for catalytic activity. The design of compounds containing multiple amine or imidazole groups that may demonstrate bifunctional catalysis is a promising route to new artificial RNases. Further design of these compounds and careful placement of catalytic groups may yield new RNase mimics that operate under physiological conditions. The attachment of artificial RNases to recognition agents such as oligodeoxynucleotides to create new sequence-specific endoribonucleases is an exciting field of

  20. Isotope geochemistry in 1990s

    SciTech Connect

    Billo, S.M.

    1995-12-31

    The intense interest in radioactive minerals as a source of atomic energy, and their application in searching for ore deposits and also in gamma-ray and neutron logging oil wells, have opened new vistas in every science. Many minerals containing elements of high atomic weight are radioactive, and emit a radiation which affects a photographic plate and may be detected by means of a sensitive phosphorescent screen. Most of the elements as found in nature are a mixture of isotopes. isotopes are atoms of one element which have different masses. Uranium, thorium, potassium, and rubidium isotopes are also used to date minerals and rocks. Organic materials that have been in equilibrium with CO{sub 2}-photosynthetic cycle during the past 50,000 years are dated by carbon-14 method. The stable isotopes of H{sub 2}, C, N{sub 2}, O{sub 2}, and S are intimately associated with the atmosphere, hydrosphere, and lithosphere and are used in probing water resources.

  1. Isotope production in fast reactor blankets

    SciTech Connect

    Zvonarev, A.V.; Koloskov, B.V.; Kochetkov, L.A.

    1993-12-31

    At the BR-10 research reactor radioactive isotopes are produced that are required for the production of radiopharmaceuticals and phosphor 32 used for the synthesis of biochemical labelled compounds. A procedure has been developed of uranium target irradiation followed by radiochemical processing aimed at isotope isolation of molybdenum 99, xenon 133 and iodine 131,132,and 133 isotopes mixture. Irradiation is carried out in a special channel of the radial blanket. The production of cobalt 60 at the BN-600 reactor and facilities are also described.

  2. Application of radioactive sources in analytical instruments for planetary exploration.

    PubMed

    Economou, Thanasis E

    2010-01-01

    Radioactive isotopes have been used in analytical instrumentation for planetary exploration since the very beginning of the space age. An Alpha Scattering Instrument (ASI) on board the Surveyor 5, 6 and 7 spacecrafts used the isotope (242)Cm to obtain the chemical composition of the lunar surface material in 1960s. The Alpha Proton X-ray Spectrometers (APXS) used on several mission to Mars (Pathfinder, Mars-96, Mars Exploration Rovers (MER) and on the Mars Science Laboratory (MSL), the next mission to Mars in 2011 and on the Rosetta mission to a comet) are improved derivatives of the original ASI, complimented with an X-ray mode and using the longer lived (244)Cm isotope. (57)Co, (55)Fe and many other radioisotopes have been used in several missions carrying XRF and Mössbauer instruments. In addition, (238)Pu isotope is exclusively being used in most of the space missions for heating and power generation. Copyright 2009. Published by Elsevier Ltd.

  3. Performance Assessment Transport Modeling of Uranium at the Area 5 Radioactive Waste Management Site at the Nevada National Security Site

    SciTech Connect

    NSTec Radioactive Waste

    2010-10-12

    Following is a brief summary of the assumptions that are pertinent to the radioactive isotope transport in the GoldSim Performance Assessment model of the Area 5 Radioactive Waste Management Site, with special emphasis on the water-phase reactive transport of uranium, which includes depleted uranium products.

  4. Artificial Intelligence.

    PubMed

    Lawrence, David R; Palacios-González, César; Harris, John

    2016-04-01

    It seems natural to think that the same prudential and ethical reasons for mutual respect and tolerance that one has vis-à-vis other human persons would hold toward newly encountered paradigmatic but nonhuman biological persons. One also tends to think that they would have similar reasons for treating we humans as creatures that count morally in our own right. This line of thought transcends biological boundaries-namely, with regard to artificially (super)intelligent persons-but is this a safe assumption? The issue concerns ultimate moral significance: the significance possessed by human persons, persons from other planets, and hypothetical nonorganic persons in the form of artificial intelligence (AI). This article investigates why our possible relations to AI persons could be more complicated than they first might appear, given that they might possess a radically different nature to us, to the point that civilized or peaceful coexistence in a determinate geographical space could be impossible to achieve.

  5. Artificial Rheotaxis

    NASA Astrophysics Data System (ADS)

    Palacci, Jeremie; Sacanna, Stefano; Abramian, Anais; Hanson, Kasey; Pine, David; Chaikin, Paul; CSMR, NYU Team

    2013-11-01

    Self propelled colloids realize a controlled realization of an artificial bacterium. However living systems present a range of advanced properties such as the migration in gradients, or taxis, based on complex conformational change of proteins. For example, rheotaxis, the directed movement of an organism resulting from a fluid flow, has been reported notably for fish, e.g. salmon, or spermatozoa. Here, we present experimental observations of artificial rheotaxis, i.e. upstream migration of self propelled particles in the presence of a flow. We will present a simple model to account for this surprising effect. In the absence of biological component, this effect is intriguing and questions the ingredients at stake in the living matter.

  6. Artificial Rheotaxis

    NASA Astrophysics Data System (ADS)

    Palacci, Jeremie; Sacanna, Stefano; Hanson, Kasey; Vatchinsky, Adrian; Pine, David; Chaikin, Paul; CSMR Team

    2013-03-01

    Self propelled colloids realize a controlled realization of an artificial bacterium. However living systems present a range of advanced properties such as the migration in gradients, or taxis, based on complex conformational change of proteins. For example, rheotaxis, the directed movement of an organism resulting from a fluid flow, has been reported notably for fish, e.g. salmon, or spermatozoa. Here, we present experimental observations of artificial rheotaxis, i.e. upstream migration of self propelled particles in the presence of a flow. We will present a simple model to account for this surprising effect. In the absence of biological component, this effect is intriguing and questions the ingredients at stake in the living matter.

  7. AIR RADIOACTIVITY MONITOR

    DOEpatents

    Bradshaw, R.L.; Thomas, J.W.

    1961-04-11

    The monitor is designed to minimize undesirable background buildup. It consists of an elongated column containing peripheral electrodes in a central portion of the column, and conduits directing an axial flow of radioactively contaminated air through the center of the column and pure air through the annular portion of the column about the electrodes. (AEC)

  8. Viewer Makes Radioactivity "Visible"

    NASA Technical Reports Server (NTRS)

    Yin, L. I.

    1983-01-01

    Battery operated viewer demonstrates feasibility of generating threedimensional visible light simulations of objects that emit X-ray or gamma rays. Ray paths are traced for two pinhold positions to show location of reconstructed image. Images formed by pinholes are converted to intensified visible-light images. Applications range from radioactivity contamination surveys to monitoring radioisotope absorption in tumors.

  9. Disposal of radioactive waste

    NASA Astrophysics Data System (ADS)

    Van Dorp, Frits; Grogan, Helen; McCombie, Charles

    The aim of radioactive and non-radioactive waste management is to protect man and the environment from unacceptable risks. Protection criteria for both should therefore be based on similar considerations. From overall protection criteria, performance criteria for subsystems in waste management can be derived, for example for waste disposal. International developments in this field are summarized. A brief overview of radioactive waste sorts and disposal concepts is given. Currently being implemented are trench disposal and engineered near-surface facilities for low-level wastes. For low-and intermediate-level waste underground facilities are under construction. For high-level waste site selection and investigation is being carried out in several countries. In all countries with nuclear programmes, the predicted performance of waste disposal systems is being assessed in scenario and consequence analyses. The influences of variability and uncertainty of parameter values are increasingly being treated by probabilistic methods. Results of selected performance assessments show that radioactive waste disposal sites can be found and suitable repositories can be designed so that defined radioprotection limits are not exceeded.

  10. Radioactive Decay - An Analog.

    ERIC Educational Resources Information Center

    McGeachy, Frank

    1988-01-01

    Presents an analog of radioactive decay that allows the student to grasp the concept of half life and the exponential nature of the decay process. The analog is devised to use small, colored, plastic poker chips or counters. Provides the typical data and a graph which supports the analog. (YP)

  11. Radioactive Decay - An Analog.

    ERIC Educational Resources Information Center

    McGeachy, Frank

    1988-01-01

    Presents an analog of radioactive decay that allows the student to grasp the concept of half life and the exponential nature of the decay process. The analog is devised to use small, colored, plastic poker chips or counters. Provides the typical data and a graph which supports the analog. (YP)

  12. Detecting Illicit Radioactive Sources

    SciTech Connect

    McDonald, Joseph C.; Coursey, Bert; Carter, Michael

    2004-11-01

    Specialized instruments have been developed to detect the presence of illicit radioactive sources that may be used by terrorists in radiation dispersal devices, so-called ''dirty bombs'' or improvised nuclear devices. This article discusses developments in devices to detect and measure radiation.

  13. Fallout Radioactivity and Epiphytes.

    Treesearch

    H. T. Odum; George Ann Briscoe; C. B. Briscoe

    1970-01-01

    After relatively high levels of fallout retention were dicovered in the epiphytic mossy forest of the Luquillo Mountains durin 1962, a survey of the distribution of radioactivity in the rain forest system was made with beta counting of 1500 samples supplemented with gamma spectra. High levels, up to 4138 counts per minute per gram, were found mainly in or on green...

  14. Radioactivity and foods

    SciTech Connect

    Olszyna-Marzys, A.E. )

    1991-01-01

    The purpose of this article is to describe and contrast two relationships between radiation and food--on the one hand, beneficial preservation of food by controlled exposure to ionizing radiation; and, on the other, contamination of food by accidental incorporation of radioactive nuclides within the food itself. In food irradiation, electrons or electromagnetic radiation is used to destroy microorganisms and insects or prevent seed germination. The economic advantages and health benefits of sterilizing food in this manner are clear, and numerous studies have confirmed that under strictly controlled conditions no undersirable changes or induced radioactivity is produced in the irradiated food. An altogether different situation is presented by exposure of food animals and farming areas to radioactive materials, as occurred after the major Soviet nuclear reactor accident at Chenobyl. This article furnishes the basic information needed to understand the nature of food contamination associated with that event and describes the work of international organizations seeking to establish appropriate safe limits for levels of radioactivity in foods.

  15. Artificial vision.

    PubMed

    Zarbin, M; Montemagno, C; Leary, J; Ritch, R

    2011-09-01

    A number treatment options are emerging for patients with retinal degenerative disease, including gene therapy, trophic factor therapy, visual cycle inhibitors (e.g., for patients with Stargardt disease and allied conditions), and cell transplantation. A radically different approach, which will augment but not replace these options, is termed neural prosthetics ("artificial vision"). Although rewiring of inner retinal circuits and inner retinal neuronal degeneration occur in association with photoreceptor degeneration in retinitis pigmentosa (RP), it is possible to create visually useful percepts by stimulating retinal ganglion cells electrically. This fact has lead to the development of techniques to induce photosensitivity in cells that are not light sensitive normally as well as to the development of the bionic retina. Advances in artificial vision continue at a robust pace. These advances are based on the use of molecular engineering and nanotechnology to render cells light-sensitive, to target ion channels to the appropriate cell type (e.g., bipolar cell) and/or cell region (e.g., dendritic tree vs. soma), and on sophisticated image processing algorithms that take advantage of our knowledge of signal processing in the retina. Combined with advances in gene therapy, pathway-based therapy, and cell-based therapy, "artificial vision" technologies create a powerful armamentarium with which ophthalmologists will be able to treat blindness in patients who have a variety of degenerative retinal diseases.

  16. Environmental Radioactivity, Temperature, and Precipitation.

    ERIC Educational Resources Information Center

    Riland, Carson A.

    1996-01-01

    Reports that environmental radioactivity levels vary with temperature and precipitation and these effects are due to radon. Discusses the measurement of this environmental radioactivity and the theory behind it. (JRH)

  17. Environmental Radioactivity, Temperature, and Precipitation.

    ERIC Educational Resources Information Center

    Riland, Carson A.

    1996-01-01

    Reports that environmental radioactivity levels vary with temperature and precipitation and these effects are due to radon. Discusses the measurement of this environmental radioactivity and the theory behind it. (JRH)

  18. Measurement of radioactivity levels and assessment of radioactivity hazards of soil samples in Karaman, Turkey.

    PubMed

    Agar, O; Boztosun, I; Korkmaz, M E; Özmen, S F

    2014-12-01

    In this study, the levels of the natural and artificial radioactivity in soil samples collected from surrounding of Karaman in Turkey were measured. Activity concentrations of the concerned radionuclides were determined by gamma-ray spectrometry using a high-purity germanium detector with a relative efficiency of 40 % at 1.332 MeV. The results obtained for the (238)U series ((226)Ra, (214)Pb and (214)Bi), (232)Th series ((228)Ac), (40)K and fission product (137)Cs are discussed. To evaluate the radiological hazard of radioactivity in samples, the radium equivalent activity (Raeq), the absorbed dose rate (D), the annual effective dose and the external (Hex) and internal hazard index (Hin) were calculated and presented in comparison with the data collected from different areas in the world and Turkey.

  19. Isotope separation

    DOEpatents

    Bartlett, Rodney J.; Morrey, John R.

    1978-01-01

    A method and apparatus is described for separating gas molecules containing one isotope of an element from gas molecules containing other isotopes of the same element in which all of the molecules of the gas are at the same electronic state in their ground state. Gas molecules in a gas stream containing one of the isotopes are selectively excited to a different electronic state while leaving the other gas molecules in their original ground state. Gas molecules containing one of the isotopes are then deflected from the other gas molecules in the stream and thus physically separated.

  20. Radioactivity as a significant energy source in prebiotic synthesis.

    PubMed

    Garzón, L; Garzón, M L

    2001-01-01

    Radioactivity in the continental crust (due mainly to the isotopes 238U, 235U, 232Th and 40K), as a energy source for chemical evolution in the early Archean (between 3.5 and approximately 4 Ga bp), is reviewed. The most important radioactive source in the continental crust is due to the production and accumulation of radioactive gases within the crust voids (porosity). The study of such mechanism has allowed us to reach a deeper understanding about the nature of the radioactive source and to describe its behavior, particularly with regard to prebiotic chemical evolution. An effective total energy of 3 x 10(18) Ja-1 has been obtained for a depth of 1 km, 4 Ga ago. If a depth of 30 km is taken, the obtained value is almost equal to the UV solar energy radiation (lambda < 150 nm). Within the voids the radioactive source of the continental crust played a relevant role in prebiotic synthesis. In uranium deposits of the same age, the role of radioactivity must have been even more relevant in favoring chemical evolution.

  1. Method for production of an isotopically enriched compound

    DOEpatents

    Watrous, Matthew G.

    2012-12-11

    A method is presented for producing and isolating an isotopically enriched compound of a desired isotope from a parent radionuclide. The method includes forming, or placing, a precipitate containing a parent radionuclide of the desired daughter isotope in a first reaction zone and allowing sufficient time for the parent to decay into the desired gaseous daughter radioisotope. The method further contemplates collecting the desired daughter isotope as a solid in a second reaction zone through the application of temperatures below the freezing point of the desired isotope to a second reaction zone that is connected to the first reaction zone. Specifically, a method is presented for producing isotopically enriched compounds of xenon, including the radioactive isotope Xe-131m and the stable isotope Xe-131.

  2. Method for calcining radioactive wastes

    DOEpatents

    Bjorklund, William J.; McElroy, Jack L.; Mendel, John E.

    1979-01-01

    This invention relates to a method for the preparation of radioactive wastes in a low leachability form by calcining the radioactive waste on a fluidized bed of glass frit, removing the calcined waste to melter to form a homogeneous melt of the glass and the calcined waste, and then solidifying the melt to encapsulate the radioactive calcine in a glass matrix.

  3. Radioactivity of peat mud used in therapy.

    PubMed

    Karpińska, Maria; Mnich, Krystian; Kapała, Jacek; Bielawska, Agnieszka; Kulesza, Grzegorz; Mnich, Stanisław

    2016-02-01

    The aim of the study was to determine the contents of natural and artificial isotopes in peat mud and to estimate the radiation dose absorbed via skin in patients during standard peat mud treatment. The analysis included 37 samples collected from 8 spas in Poland. The measurements of isotope concentration activity were conducted with the use of gamma spectrometry methods. The skin dose in a standard peat mud bath therapy is approximately 300 nSv. The effective dose of such therapy is considered to be 22 nSv. The doses absorbed during peat mud therapy are 5 orders of magnitude lower than effective annual dose absorbed from the natural radiation background by a statistical Pole (3.5 mSv). Neither therapeutic nor harmful effect is probable in case of such a small dose of ionising radiation.

  4. Stable Isotope Spectroscopy for Diagnostic Medicine

    NASA Astrophysics Data System (ADS)

    Murnick, D. E.

    2000-06-01

    Isotopic tracers have been used in medical research for more than fifty years. Radioactive isotopes have been most used because of the high detection efficiencies possible. With increased awareness of the effects of low level radiation and radioactive waste management problems, the need for safe non radioactive tracers has become apparent. Rare stable isotopes of biologically active elements can be used for metabolic and pharmacokinetic studies provided that both sufficient detection sensitivity can be achieved and reliable cost effective instruments can be developed. High resolution optical spectroscopic methods which can determine isotopic ratios with high precision and accuracy are viable for research and clinical use. The study of 13C/12C ratios in CO2 for breath test diagnostics will be described in detail. Using the laser optogalvonic effect with isotopic lasers a specific medical diagnostic for h-pylori infection, has recently received FDA approval. Opportunities exist to study D/H ratios in water and 18O/16O ratios in CO2 and water for basic metabolism diagnostics and 15N/14N ratios in urine for liver function and related studies.

  5. Selected Isotopes for Optimized Fuel Assembly Tags

    SciTech Connect

    Gerlach, David C.; Mitchell, Mark R.; Reid, Bruce D.; Gesh, Christopher J.; Hurley, David E.

    2008-10-01

    In support of our ongoing signatures project we present information on 3 isotopes selected for possible application in optimized tags that could be applied to fuel assemblies to provide an objective measure of burnup. 1. Important factors for an optimized tag are compatibility with the reactor environment (corrosion resistance), low radioactive activation, at least 2 stable isotopes, moderate neutron absorption cross-section, which gives significant changes in isotope ratios over typical fuel assembly irradiation levels, and ease of measurement in the SIMS machine 2. From the candidate isotopes presented in the 3rd FY 08 Quarterly Report, the most promising appear to be Titanium, Hafnium, and Platinum. The other candidate isotopes (Iron, Tungsten, exhibited inadequate corrosion resistance and/or had neutron capture cross-sections either too high or too low for the burnup range of interest.

  6. Stable isotope inventory requirements and enrichment capabilities

    SciTech Connect

    Bell, W.A.; Tracy, J.G.

    1985-12-01

    The electromagnetic isotope enrichment program established in 1945 has since then continued to provide enriched stable, actinide, and selected radioactive isotopes. These unique materials used in research and medicine and for industrial applications are made available throughout the world by direct sales and/or on a loan basis. In recent years, the primary effort of the program has been directed toward providing enriched stable isotopes necessary to replenish the sales inventory. This document presents a summary of the stable isotope sales requirements and the capabilities of the electromagnetic isotope separators for providing the quantity and quality of enriched products to meet those needs. Special enrichment and actinide separations or Research Materials Collection (loan program) needs are not addressed.

  7. 137Cs(90Sr) and Pu isotopes in the Pacific Ocean sources & trends

    SciTech Connect

    Hamilton, T.F., Millies-Lacrox, J.C.; Hong, G.H.

    1996-11-01

    The main source of artificial radioactivity in the world`s oceans can be attributed to worldwide fallout from atmospheric nuclear weapons testing. Measurements of selected artificial radionuclides in the Pacific Ocean were first conducted in the 1960`s where it was observed that fallout radioactivity had penetrated the deep ocean. Extensive studies carried out during the 1973-74 GEOSECS provided the first comprehensive data on the lateral and vertical distributions of {sup 9O}Sr, {sup 137}Cs and Pu isotopes in the Pacific on a basin wide scale. Estimates of radionuclide inventories in excess of amounts predicted to be delivered by global fallout alone were attributed to close-in fallout and tropospheric inputs from early U.S. tests conducted on Bikini and Enewetak Atolls in the Equatorial Pacific. In general, levels of fallout radionuclides (including {sup 9O}Sr, {sup 137}Cs and Pu isotopes) in the surface waters of the Pacific Ocean have decreased considerably over the past 4 decades and are now much more homogeneously distributed. Resuspension and the subsequent deposition of fallout radionuclides from previously deposited debris on land has become an important source term for the surface ocean. This can be clearly seen in measurements of fallout radionuclides in mineral aerosols over the Korean Peninsula (Yellow dust events). Radionuclides may also be transported from land to sea in river runoff-these transport mechanisms are more important in the Pacific Ocean where large quantities of river water and suspended sands/fluvial sediments reach the coastal zone. Another unique source of artificial radionuclides in the Pacific Ocean is derived from the slow resolubilization and transport of radionuclides deposited in contaminated lagoon and slope sediments near U.S. and French test sites. Although there is a small but significant flux of artificial radionuclides depositing on the sea floor, > 80% of the total 239, {sup 240}Pu inventory and > 95% of the total {sup

  8. Calcium and titanium isotopic fractionations during evaporation

    NASA Astrophysics Data System (ADS)

    Zhang, Junjun; Huang, Shichun; Davis, Andrew M.; Dauphas, Nicolas; Hashimoto, Akihiko; Jacobsen, Stein B.

    2014-09-01

    Isotope fractionations associated with high temperature evaporation provide important constraints on the physicochemical processes that affected planetary materials at the birth of the solar system. Previous evaporation experiments have focused on isotopic fractionation of moderately to highly volatile elements. Here, we investigate the isotope fractionation behavior of two highly refractory elements, calcium and titanium, during evaporation of perovskite (CaTiO3) in a vacuum furnace. In our experiments, isotope fractionation during evaporation follows the Rayleigh law, but not the commonly used exponential law, with the dominant evaporating species being Ca(g) and TiO2(g). If isotope fractionations in early solar system materials did follow the Rayleigh law, the common practice of using an exponential fractionation law to correct for mass-dependent fractionation in the study of mass-independent fractionations may introduce significant artificial isotope anomalies.

  9. Radioactive fallouts as temporal makers for glacier ice cores dating

    NASA Astrophysics Data System (ADS)

    Clemenza, M.; Cucciati, G.; Maggi, V.; Pattavina, L.; Previtali, E.

    2012-06-01

    In this paper, we intend to show how analytical methods used in nuclear physics, as gamma spectroscopy, are powerful tools for the dating of environmental archives. Specifically, we will show how events related to the release in the environment of great amount of radioactive isotopes ( e.g., atmospheric nuclear test explosions) can be used as temporal markers in alpine glaciers. The radio-isotope selected for the dating of ice carrots is 137Cs , because of its chemical and nuclear properties. The radioactive measurements have been conducted using a low-background high-purity germanium detector. The sensitivity for the prepared samples is 10mBq/kg. We will illustrate how dating curves (date versus depth of the sample) can be considered as an absolute calibrator for all the other chemical dating methods used on glacier samples analyses.

  10. Possibilities of production of transfermium nuclei in complete fusion reactions with radioactive beams

    NASA Astrophysics Data System (ADS)

    Hong, Juhee; Adamian, G. G.; Antonenko, N. V.

    2017-07-01

    The possibilities of direct production of new isotopes of transfermium nuclei 261,263,264No, 264Lr263, 263,264,266,268Rf, 265Db264, and 267,268,270,272Sg are studied in various asymmetric hot fusion-evaporation reactions with radioactive beams. The optimal reaction partners and conditions for the synthesis of new isotopes are suggested. The products of the suggested reactions can fill a gap of unknown isotopes between the isotopes of heaviest nuclei obtained in the x n evaporation channels of the cold and hot complete fusion reactions with the stable beams.

  11. International radioactive material recycling challenges

    SciTech Connect

    Greeves, John T.; Lieberman, James

    2007-07-01

    The paper explores current examples of successful International radioactive recycling programs and also explores operational regulatory and political challenges that need to be considered for expanding international recycling world-wide. Most countries regulations are fully consistent with the International Atomic Agency (IAEA) Code of Practice on the International Transboundary Movement of Radioactive Material and the IAEA Code of Conduct on the Safety and Security of Radioactive Sources. IAEA member States reported on the status of their efforts to control transboundary movement of radioactive material recently during the Joint Convention on the Safety of Spent Fuel management and on the Safety of Radioactive Waste Management meeting in May 2006. (authors)

  12. Initial report on the application of laser ablation - inductively coupled plasma mass spectrometry for the analysis of radioactive Hanford Tank Waste materials

    SciTech Connect

    Smith, M.R.; Hartman, J.S.; Alexander, M.L.; Mendoza, A.; Hirt, E.H.; Stewart, T.L.; Hansen, M.A.; Park, W.R.; Peters, T.J.; Burghard, B.J.

    1996-12-01

    Initial LA/MS analyses of Hanford tank waste samples were performed successfully using laboratory and hot cell LA/MS instrumentation systems. The experiments described in this report have demonstrated that the LA/MS data can be used to provide rapid analysis of solid, radioactive Hanford tank waste samples to identify major, minor, and trace constituents (elemental and isotopic) and fission products and radioactive isotopes. The ability to determine isotopic constituents using the LA/MS method yielded significant advantages over ICP/AES analysis by providing valuable information on fission products and radioactive constituents.

  13. Understanding the Radioactive Ingrowth and Decay of Naturally Occurring Radioactive Materials in the Environment: An Analysis of Produced Fluids from the Marcellus Shale

    PubMed Central

    Nelson, Andrew W.; Eitrheim, Eric S.; Knight, Andrew W.; May, Dustin; Mehrhoff, Marinea A.; Shannon, Robert; Litman, Robert; Burnett, William C.; Forbes, Tori Z.

    2015-01-01

    Background The economic value of unconventional natural gas resources has stimulated rapid globalization of horizontal drilling and hydraulic fracturing. However, natural radioactivity found in the large volumes of “produced fluids” generated by these technologies is emerging as an international environmental health concern. Current assessments of the radioactivity concentration in liquid wastes focus on a single element—radium. However, the use of radium alone to predict radioactivity concentrations can greatly underestimate total levels. Objective We investigated the contribution to radioactivity concentrations from naturally occurring radioactive materials (NORM), including uranium, thorium, actinium, radium, lead, bismuth, and polonium isotopes, to the total radioactivity of hydraulic fracturing wastes. Methods For this study we used established methods and developed new methods designed to quantitate NORM of public health concern that may be enriched in complex brines from hydraulic fracturing wastes. Specifically, we examined the use of high-purity germanium gamma spectrometry and isotope dilution alpha spectrometry to quantitate NORM. Results We observed that radium decay products were initially absent from produced fluids due to differences in solubility. However, in systems closed to the release of gaseous radon, our model predicted that decay products will begin to ingrow immediately and (under these closed-system conditions) can contribute to an increase in the total radioactivity for more than 100 years. Conclusions Accurate predictions of radioactivity concentrations are critical for estimating doses to potentially exposed individuals and the surrounding environment. These predictions must include an understanding of the geochemistry, decay properties, and ingrowth kinetics of radium and its decay product radionuclides. Citation Nelson AW, Eitrheim ES, Knight AW, May D, Mehrhoff MA, Shannon R, Litman R, Burnett WC, Forbes TZ, Schultz MK. 2015

  14. Studies of muon-induced radioactivity at NuMI

    SciTech Connect

    Boehnlein, David j.; Leveling, A.F.; Mokhov, N.V.; Vaziri, K.; Iwamoto, Y.; Kasugai, Y.; Matsuda, N.; Nakashima, H.; Sakamoto, Y.; Hagiwara, M.; Iwase, Hiroshi; /KEK, Tsukuba /Kyoto U., KURRI /Pohang Accelerator Lab. /Shimizu, Tokyo /Tohoku U.

    2009-12-01

    The JASMIN Collaboration has studied the production of radionuclides by muons in the muon alcoves of the NuMI beamline at Fermilab. Samples of aluminum and copper are exposed to the muon field and counted on HpGe detectors when removed to determine their content of radioactive isotopes. We compare the results to MARS simulations and discuss the radiological implications for neutrino factories and muon colliders.

  15. Radioactive Cs capture in the early solar system

    PubMed Central

    Hidaka, Hiroshi; Yoneda, Shigekazu

    2013-01-01

    Barium isotopic compositions of primitive materials in the solar system are generally affected by s- and r-process nucleosynthetic components that hide the contribution of the isotopic excess of 135Ba formed by decay of radioactive 135Cs. However, the Ba isotopic composition of the chemical separates from chondrules in the Sayama CM2 chondrite shows an excess of 135Ba isotopic abundance up to (0.33 ± 0.06)%, which is independent of the isotopic components from s- and r-process nucleosyntheses. The isotopic excesses of 135Ba correlate with the elemental abundance of Ba relative to Cs, providing chemical and isotopic evidence for the existence of the presently extinct radionuclide 135Cs (t1/2 = 2.3 million years) in the early solar system. The estimated abundance of 135Cs/133Cs = (6.8 ± 1.9) × 10−4 is more than double that expected from the uniform production model of the short-lived radioisotopes, suggesting remobilization of Cs including 135Cs in the chondrules of the meteorite parent body. PMID:23435551

  16. Radioactive ion detector

    DOEpatents

    Bower, Kenneth E.; Weeks, Donald R.

    1997-01-01

    Apparatus for detecting the presence, in aqueous media, of substances which emit alpha and/or beta radiation and determining the oxidation state of these radioactive substances, that is, whether they are in cationic or anionic form. In one embodiment, a sensor assembly has two elements, one comprised of an ion-exchange material which binds cations and the other comprised of an ion-exchange material which binds anions. Each ion-exchange element is further comprised of a scintillation plastic and a photocurrent generator. When a radioactive substance to which the sensor is exposed binds to either element and emits alpha or beta particles, photons produced in the scintillation plastic illuminate the photocurrent generator of that element. Sensing apparatus senses generator output and thereby indicates whether cationic species or anionic species or both are present and also provides an indication of species quantity.

  17. Radioactive ion detector

    DOEpatents

    Bower, K.E.; Weeks, D.R.

    1997-08-12

    Apparatus for detecting the presence, in aqueous media, of substances which emit alpha and/or beta radiation and determining the oxidation state of these radioactive substances, that is, whether they are in cationic or anionic form. In one embodiment, a sensor assembly has two elements, one comprised of an ion-exchange material which binds cations and the other comprised of an ion-exchange material which binds anions. Each ion-exchange element is further comprised of a scintillation plastic and a photocurrent generator. When a radioactive substance to which the sensor is exposed binds to either element and emits alpha or beta particles, photons produced in the scintillation plastic illuminate the photocurrent generator of that element. Sensing apparatus senses generator output and thereby indicates whether cationic species or anionic species or both are present and also provides an indication of species quantity. 2 figs.

  18. Chernobyl three years later: radiobiologic evaluation of a radioactive contamination

    SciTech Connect

    Behar, A.; Cohen-Boulakia, F.; Othmani, S. )

    1990-11-01

    On April 26, 1986, after partial fusion and confining loss by explosion of a nuclear reactor, 5 x 10(7) Ci of radionuclides escaped from Chernobyl. Three years later, maps show contamination by radioactive isotopes (formed during that period) of 21,000 km2 of Soviet soil, mainly in Byelorussia and part of the Ukraine. Decontamination measures have not been effective to date and 135,000 persons are being followed medically, taking into account the radioactive doses they received. An initial excess of morbidity from solid tumors has been noted much sooner than in the case of Hiroshima and Nagasaki, but its significance is in dispute. Three years later, only the extent of the ecologic disaster caused by the radioactive contamination can be confirmed. It is too early to draw conclusions about radiation-induced carcinogenesis for the contaminated population.

  19. MARE: Mars Radioactivity Experiment

    NASA Astrophysics Data System (ADS)

    di Lellis, A. M.; Capria, M. T.; Espinasse, S.; Magni, G.; Orosei, R.; Piccioni, G.; Federico, C.; Minelli, G.; Pauselli, C.; Scarpa, G.

    1999-09-01

    MARE is an experiment for the measurement of the beta and gamma radioactivity in space and in the Martian soil, both at the surface and in the subsurface. This will be accomplished by means of a dosimeter and a spectrometer. The radiation dose rate to which crews will be exposed is one of the hazards that has to be quantified before the human exploration of Mars may begin. Data for evaluating radioactivity levels at Martian surface are of great interest for environmental studies related to life in general. The dosimeter will be able to measure the beta and gamma radiation dose received, with a responsivity which is very close to that of a living organism. The dosimeter is based on thermo-luminescence pills which emit an optical signal proportional to the absorbed dose when heated. Radioactive elements ((40) K, (235) U, (238) U and (232) Th) can be used as a mean of tracing the evolution of a terrestrial planet. These radioactive elements are the source of the internal heat, which drives convection in the mantle. They have been redistributed in this process and they are now concentrated in the crust where they are accessible for study. Their different behavior during the fractionation process can be used as a mean to investigate the geochemical characteristic of Mars. The spectrometer, a scintillation radiation absorber system for single event counting, is capable of detecting gamma photons with energies between 200 KeV and 10 MeV. The detected events will be processed in such a way to allow the recognition of the spectral signature of different decay processes, and thus the identification and the measurement of the concentrations of different radionuclides in the Martian soil.

  20. PROCESSING OF RADIOACTIVE WASTE

    DOEpatents

    Johnson, B.M. Jr.; Barton, G.B.

    1961-11-14

    A process for treating radioactive waste solutions prior to disposal is described. A water-soluble phosphate, borate, and/or silicate is added. The solution is sprayed with steam into a space heated from 325 to 400 deg C whereby a powder is formed. The powder is melted and calcined at from 800 to 1000 deg C. Water vapor and gaseous products are separated from the glass formed. (AEC)

  1. Radioactive waste storage issues

    SciTech Connect

    Kunz, Daniel E.

    1994-08-15

    In the United States we generate greater than 500 million tons of toxic waste per year which pose a threat to human health and the environment. Some of the most toxic of these wastes are those that are radioactively contaminated. This thesis explores the need for permanent disposal facilities to isolate radioactive waste materials that are being stored temporarily, and therefore potentially unsafely, at generating facilities. Because of current controversies involving the interstate transfer of toxic waste, more states are restricting the flow of wastes into - their borders with the resultant outcome of requiring the management (storage and disposal) of wastes generated solely within a state`s boundary to remain there. The purpose of this project is to study nuclear waste storage issues and public perceptions of this important matter. Temporary storage at generating facilities is a cause for safety concerns and underscores, the need for the opening of permanent disposal sites. Political controversies and public concern are forcing states to look within their own borders to find solutions to this difficult problem. Permanent disposal or retrievable storage for radioactive waste may become a necessity in the near future in Colorado. Suitable areas that could support - a nuclear storage/disposal site need to be explored to make certain the health, safety and environment of our citizens now, and that of future generations, will be protected.

  2. Radioactive deposits of Nevada

    USGS Publications Warehouse

    Lovering, T.G.

    1954-01-01

    Thirty-five occurrences of radioactive rocks had been reported from Nevada prior to 1952. Twenty-five of these had been investigated by personnel of the U. S. Geological Surveyor of the U. S. Atomic Energy Commission. Of those investigated, uranium minerals were identified at 13 sites; two sites contained a thorium mineral (monazite); the source of radioactivity on nine properties was not ascertained, and one showed no abnormal radioactivity. Of the other reported occurrences, one is said to contain uraniferous hydrocarbons and nine are placers containing thorian monazite. Pitchblende occurs at two localities, the East Walker River area, and the Stalin's Present prospect, where it is sparsely disseminated in tabular bodies cutting granitic rocks. Other uranium minerals found in the state include: carnotite, tyuyamunite, autunite, torbernite, gummite, uranophane, kasolite, and an unidentified mineral which may be dumontite. Monazite is the only thorium mineral of possible economic importance that has been reported. From an economic standpoint, only four of the properties examined showed reserves of uranium ore in 1952; these are: the Green Monster mine, which shipped 5 tons of ore to Marysvale, Utah, during 1951; the Majuba Hill mine; the Stalin's Present prospect; and the West Willys claim in the Washington district. No estimate has been made of thorium reserves and no commercial deposits of thorium are known.

  3. Radioactive deposits of Nevada

    USGS Publications Warehouse

    Lovering, T.G.

    1953-01-01

    Thirty-five occurrences of radioactive rocks had been reported from Nevada prior to 1952. Twenty-five of these had been investigated by the U. S. Geological Survey and the U. S. Atomic Energy Commission. Of those investigated, uranium minerals were identified in 13; two contained a thorium mineral (monazite); the source of radioactivity on 7 properties was not ascertained; and one showed no abnormal radioactivity. Of the other reported occurrences, one is said to contain uraniferous hydrocarbons and 9 are placers containing thorian monazite. Pitchblende occurs at two localities; the East Walker River area, and the Stalin's Present prospect, where it is sparsely disseminated in tabular bodies cutting granitic rocks. Other uranium minerals found in the state include: carnotite, tyuyamunite, autunite, torbernite, gummite, uranophane, kasolite, and an unidentified mineral which may be dumontit. Monazite is the only thorium mineral of possible economic importance that has been reported. From an economic standpoint 9 only 4 of the properties examined showed reserves of uranium ore in 1952; these are: the Green Monster mine, which shipped 5 tons of ore to Marysvale, Utah, during 1951, the Majuba Hill mine, the Stalin's Present prospect, and the West Willys claim in the Washington district. Reserves of ore grade are small on all of these properties and probably cannot be developed commercially unless an ore-buying station is set up nearby. No estimate has been made of thorium reserves and no commercial deposits of thorium are known.

  4. ISOL science at the Holifield Radioactive Ion Beam Facility

    NASA Astrophysics Data System (ADS)

    Beene, J. R.; Bardayan, D. W.; Galindo Uribarri, A.; Gross, C. J.; Jones, K. L.; Liang, J. F.; Nazarewicz, W.; Stracener, D. W.; Tatum, B. A.; Varner, R. L.

    2011-02-01

    The Holifield Radioactive Ion Beam Facility (HRIBF) provides high-quality Isotope Separator Online beams of short-lived, radioactive nuclei for nuclear structure and reaction studies, astrophysics research, and interdisciplinary applications. The primary driver, the Oak Ridge Isochronous Cyclotron, produces rare isotopes by bombarding highly refractory targets with light ions. The radioactive isotopes are ionized, formed into a beam, mass selected, injected into the 25 MV tandem, accelerated, and used in experiments. This paper reviews the HRIBF and its users' science. Note that this manuscript has been authored by UT-Battelle, LLC, under Contract No. DE-AC05-00OR22725 with the U.S. Department of Energy. The United States Government retains and the publisher, by accepting the article for publication, acknowledges that the United States Government retains a non-exclusive, paid-up irrevocable, world-wide license to publish or reproduce the published form of the manuscript, or allow others to do so, for United States Government purposes.

  5. ASSESSMENT OF RADIOACTIVE AND NON-RADIOACTIVE CONTAMINANTS FOUND IN LOW LEVEL RADIOACTIVE WASTE STREAMS

    SciTech Connect

    R.H. Little, P.R. Maul, J.S.S. Penfoldag

    2003-02-27

    This paper describes and presents the findings from two studies undertaken for the European Commission to assess the long-term impact upon the environment and human health of non-radioactive contaminants found in various low level radioactive waste streams. The initial study investigated the application of safety assessment approaches developed for radioactive contaminants to the assessment of nonradioactive contaminants in low level radioactive waste. It demonstrated how disposal limits could be derived for a range of non-radioactive contaminants and generic disposal facilities. The follow-up study used the same approach but undertook more detailed, disposal system specific calculations, assessing the impacts of both the non-radioactive and radioactive contaminants. The calculations undertaken indicated that it is prudent to consider non-radioactive, as well as radioactive contaminants, when assessing the impacts of low level radioactive waste disposal. For some waste streams with relatively low concentrations of radionuclides, the potential post-closure disposal impacts from non-radioactive contaminants can be comparable with the potential radiological impacts. For such waste streams there is therefore an added incentive to explore options for recycling the materials involved wherever possible.

  6. Isotopic Randomness and Maxwell's Demon

    NASA Astrophysics Data System (ADS)

    Berezin, Alexander A.

    2005-03-01

    Isotopic disorder in crystals can lead to suppression of thermal conductivity, mobility variations and (weak) Anderson localization on isotopic fluctuations. The latter (AAB, J.ChemPhys.1984) is akin to polaron effect (self-localization due polarization). Possibility of isotopic patterning (IP) increases near melting point (thermally activated isotopic hopping swaps). Crystal near melting threshold become “informationally sensitive” as if its IP is operated by some external Maxwell’s Demon, MD (AAB, URAM J, 2002). At this state short range (e.g. electrostatic inverse square) forces evolve into long-range interactions (due to divergence of order parameter) and information sensitivity can be further amplified by (say) a single fast electron (e.g. beta-particle from decay of 14-C or other radioactive isotope) which may result in cascade of impact ionization events and (short time-scale) enhancement of screening by impact-generated non-equilibrium (non-thermal) electrons. In this state informationally driven (MD-controlled) IP (Eccles effect) can result in decrease of positional entropy signifying emergence of physical complexity out of pure information, similar to peculiar “jinni effect” on closed time loops in relativistic cosmology (R.J.Gott, 2001) or Wheeler’s “it from bit” metaphor. By selecting special IP, MD modifies ergodicity principle in favor of info rich states.

  7. Artificial rheotaxis.

    PubMed

    Palacci, Jérémie; Sacanna, Stefano; Abramian, Anaïs; Barral, Jérémie; Hanson, Kasey; Grosberg, Alexander Y; Pine, David J; Chaikin, Paul M

    2015-05-01

    Motility is a basic feature of living microorganisms, and how it works is often determined by environmental cues. Recent efforts have focused on developing artificial systems that can mimic microorganisms, in particular their self-propulsion. We report on the design and characterization of synthetic self-propelled particles that migrate upstream, known as positive rheotaxis. This phenomenon results from a purely physical mechanism involving the interplay between the polarity of the particles and their alignment by a viscous torque. We show quantitative agreement between experimental data and a simple model of an overdamped Brownian pendulum. The model notably predicts the existence of a stagnation point in a diverging flow. We take advantage of this property to demonstrate that our active particles can sense and predictably organize in an imposed flow. Our colloidal system represents an important step toward the realization of biomimetic microsystems with the ability to sense and respond to environmental changes.

  8. Artificial Hydrogenases

    PubMed Central

    Barton, Bryan E.; Olsen, Matthew T.; Rauchfuss, Thomas B.

    2010-01-01

    Decades of biophysical study on the hydrogenase (H2ase) enzymes have yielded sufficient information to guide the synthesis of analogues of their active sites. Three families of enzymes serve as inspiration for this work: the [FeFe]-, [NiFe]-, and [Fe]-H2ases, all of which feature iron centers bound to both CO and thiolate. Artificial H2ases effect the oxidation of H2 of H2 and the reverse reaction, the reduction of protons. These reactions occur via the intermediacy of metal hydrides. The inclusion of amine bases within the catalysts is an important design feature that is emulated in related bioinspired catalysts. Continuing challenges are the low reactivity of H2 towards biomimetic H2ases. PMID:20356731

  9. Artificial gravity.

    PubMed

    Scott, William B

    2005-04-25

    NASA's Artificial Gravity program consists of a team of researchers from Wyle Laboratories, NASA Johnson Space Center, and the University of Texas Medical Branch (UTMB). The short-radius centrifuge (SRC), built by Wyle Laboratories, will be integrated with UTMB's conducted bedrest studies, which mimic the detrimental effects of weightlessness (or microgravity). Bedrest subjects will be spun on the SRC at various accelerations and for various time periods, while being monitored medically. Parameters such as bone loss, muscle atrophy, balance control, and oxygen consumption will then be compared in order to research ways of mitigating the impact on astronauts' physiology. Other potential benefits from these studies extend to population groups on Earth, such as bedridden patients.

  10. E-Alerts: Nuclear science and technology (radioactive wastes and radioactivity). E-mail newsletter

    SciTech Connect

    1999-05-01

    The newsletter discusses the following: Separation, processing, handling, storage, disposal, and reuse of radioactive wastes; Radioactive fallout; Fission products; Man-made or natural radioactivity; and Decommissioning.

  11. THE ATOMIC WEIGHTS COMMISSION AND ISOTOPIC ABUNDANCE RATIO DETERMINATIONS.

    SciTech Connect

    HOLDEN, N.E.

    2005-08-07

    Following Thomson's discovery of stable isotopes in non-radioactive chemical elements, the derivation of atomic weight values from mass spectrometric measurements of isotopic abundance ratios moved very slowly. Forty years later, only 3 1/2 % of the recommended values were based on mass spectrometric measurements and only 38% in the first half century. It might be noted that two chemical elements (tellurium and mercury) are still based on chemical measurements, where the atomic weight value calculated from the relative isotopic abundance measurement either agrees with the value from the chemical measurement or the atomic weight value calculated from the relative isotopic abundance measurement falls within the uncertainty of the chemical measurement of the atomic weight. Of the 19 chemical elements, whose atomic weight is based on non-corrected relative isotopic abundance measurements, five of these are two isotope systems (indium, iridium, lanthanum, lutetium and tantalum) and one is a three-isotope system (oxygen).

  12. Lunar and Planetary Science XXXV: Isotopes in Meteorites

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The session"Isotopes in Meteorites" consisted of the following presentations:The Common Property of Isotopic Anomalies in Meteorites; Revised Production Rates for 22Na and 54Mn in Meteorites Using Cross Sections Measured for Neutron-induced Reactions; Modeling of 14C and 10Be Production Rates in Meteorites and Lunar Samples; Investigating Xenon Isotopic Fractionation During Rayleigh-type Distillation; The Mean Life Squared Relationship for Abundances of Extinct Radioactivities; and Magnesium Isotopic Fractionation of Forsterite During Evaporation from Different Crystallographic Surfaces.

  13. Lunar and Planetary Science XXXV: Isotopes in Meteorites

    NASA Technical Reports Server (NTRS)

    2004-01-01

    The session"Isotopes in Meteorites" consisted of the following presentations:The Common Property of Isotopic Anomalies in Meteorites; Revised Production Rates for 22Na and 54Mn in Meteorites Using Cross Sections Measured for Neutron-induced Reactions; Modeling of 14C and 10Be Production Rates in Meteorites and Lunar Samples; Investigating Xenon Isotopic Fractionation During Rayleigh-type Distillation; The Mean Life Squared Relationship for Abundances of Extinct Radioactivities; and Magnesium Isotopic Fractionation of Forsterite During Evaporation from Different Crystallographic Surfaces.

  14. Study of proton radioactivities

    SciTech Connect

    Davids, C.N.; Back, B.B.; Henderson, D.J.

    1995-08-01

    About a dozen nuclei are currently known to accomplish their radioactive decay by emitting a proton. These nuclei are situated far from the valley of stability, and mark the very limits of existence for proton-rich nuclei: the proton drip line. A new 39-ms proton radioactivity was observed following the bombardment of a {sup 96}Ru target by a beam of 420-MeV {sup 78}Kr. Using the double-sided Si strip detector implantation system at the FMA, a proton group having an energy of 1.05 MeV was observed, correlated with the implantation of ions having mass 167. The subsequent daughter decay was identified as {sup 166}Os by its characteristic alpha decay, and therefore the proton emitter is assigned to the {sup 167}Ir nucleus. Further analysis showed that a second weak proton group from the same nucleus is present, indicating an isomeric state. Two other proton emitters were discovered recently at the FMA: {sup 171}Au and {sup 185}Bi, which is the heaviest known proton radioactivity. The measured decay energies and half-lives will enable the angular momentum of the emitted protons to be determined, thus providing spectroscopic information on nuclei that are beyond the proton drip line. In addition, the decay energy yields the mass of the nucleus, providing a sensitive test of mass models in this extremely proton-rich region of the chart of the nuclides. Additional searches for proton emitters will be conducted in the future, in order to extend our knowledge of the location of the proton drip line.

  15. The Isotope Exchange Method for Measuring Saturated Vapor Pressure and Diffusion coefficients - USSR -

    DTIC Science & Technology

    1960-06-16

    The availability of convenient radioactive isotopes of almost all elements of the periodic table makes this method universally applicable to the practical study of any substance in its condensed state.

  16. Radioactivity-synchronized fluorescence enhancement using a radionuclide fluorescence-quenched dye.

    PubMed

    Berezin, Mikhail Y; Guo, Kevin; Teng, Bao; Edwards, W Barry; Anderson, Carolyn J; Vasalatiy, Olga; Gandjbakhche, Amir; Griffiths, Gary L; Achilefu, Samuel

    2009-07-08

    We demonstrate the first evidence of radioactivity-synchronized fluorescence quenching of a near-infrared light-emitting dye by a radionuclide, (64)Cu, and subsequent fluorescence enhancement upon (64)Cu decay to the daughter isotopes (64)Ni and (64)Zn. The dynamic switch from high radioactivity and low fluorescence to low radioactivity and high fluorescence is potentially useful for developing complementary multimodal imaging and detection platforms for chemical, environmental, and biomedical applications as well as for unraveling the mechanisms of metal-induced dynamic fluorescence changes.

  17. Radioactive nondestructive test method

    NASA Technical Reports Server (NTRS)

    Obrien, J. R.; Pullen, K. E.

    1971-01-01

    Various radioisotope techniques were used as diagnostic tools for determining the performance of spacecraft propulsion feed system elements. Applications were studied in four tasks. The first two required experimental testing involving the propellant liquid oxygen difluoride (OF2): the neutron activation analysis of dissolved or suspended metals, and the use of radioactive tracers to evaluate the probability of constrictions in passive components (orifices and filters) becoming clogged by matter dissolved or suspended in the OF2. The other tasks were an appraisal of the applicability of radioisotope techniques to problems arising from the exposure of components to liquid/gas combinations, and an assessment of the applicability of the techniques to other propellants.

  18. Material for radioactive protection

    DOEpatents

    Taylor, R.S.; Boyer, N.W.

    A boron containing burn resistant, low-level radiation protection material useful, for example, as a liner for radioactive waste disposal and storage, a component for neutron absorber, and a shield for a neutron source is described. The material is basically composed of borax in the range of 25 to 50%, coal tar in the range of 25 to 37.5%, with the remainder being an epoxy resin mix. A preferred composition is 50% borax, 25% coal tar and 25% epoxy resin. The material is not susceptible to burning and is about 1/5 the cost of existing radiation protection material utilized in similar applications.

  19. Radioactive waste material disposal

    DOEpatents

    Forsberg, C.W.; Beahm, E.C.; Parker, G.W.

    1995-10-24

    The invention is a process for direct conversion of solid radioactive waste, particularly spent nuclear fuel and its cladding, if any, into a solidified waste glass. A sacrificial metal oxide, dissolved in a glass bath, is used to oxidize elemental metal and any carbon values present in the waste as they are fed to the bath. Two different modes of operation are possible, depending on the sacrificial metal oxide employed. In the first mode, a regenerable sacrificial oxide, e.g., PbO, is employed, while the second mode features use of disposable oxides such as ferric oxide. 3 figs.

  20. Radioactive waste material disposal

    DOEpatents

    Forsberg, Charles W.; Beahm, Edward C.; Parker, George W.

    1995-01-01

    The invention is a process for direct conversion of solid radioactive waste, particularly spent nuclear fuel and its cladding, if any, into a solidified waste glass. A sacrificial metal oxide, dissolved in a glass bath, is used to oxidize elemental metal and any carbon values present in the waste as they are fed to the bath. Two different modes of operation are possible, depending on the sacrificial metal oxide employed. In the first mode, a regenerable sacrificial oxide, e.g., PbO, is employed, while the second mode features use of disposable oxides such as ferric oxide.

  1. Radioactive Liquid Waste Treatment Facility Discharges in 2011

    SciTech Connect

    Del Signore, John C.

    2012-05-16

    This report documents radioactive discharges from the TA50 Radioactive Liquid Waste Treatment Facilities (RLWTF) during calendar 2011. During 2011, three pathways were available for the discharge of treated water to the environment: discharge as water through NPDES Outfall 051 into Mortandad Canyon, evaporation via the TA50 cooling towers, and evaporation using the newly-installed natural-gas effluent evaporator at TA50. Only one of these pathways was used; all treated water (3,352,890 liters) was fed to the effluent evaporator. The quality of treated water was established by collecting a weekly grab sample of water being fed to the effluent evaporator. Forty weekly samples were collected; each was analyzed for gross alpha, gross beta, and tritium. Weekly samples were also composited at the end of each month. These flow-weighted composite samples were then analyzed for 37 radioisotopes: nine alpha-emitting isotopes, 27 beta emitters, and tritium. These monthly analyses were used to estimate the radioactive content of treated water fed to the effluent evaporator. Table 1 summarizes this information. The concentrations and quantities of radioactivity in Table 1 are for treated water fed to the evaporator. Amounts of radioactivity discharged to the environment through the evaporator stack were likely smaller since only entrained materials would exit via the evaporator stack.

  2. SPI cosmic radioactivity measurements in perspective

    NASA Astrophysics Data System (ADS)

    Schönfelder, V.

    2002-07-01

    The ESA-Mission INTEGRAL (International Gamma-Ray Astrophysics Laboratory) is the next step in low-energy gamma-ray astronomy (up to 10 MeV) and will be launched in 2002. The spectrometer SPI—one of its two main instruments—is dedicated to high-resolution line spectroscopy (Δ E=2.5 keV FWHM at 1.3 MeV). SPI will concentrate on the study of lines from radioactive isotopes. A wealth of new information is expected from interstellar line emission with narrow line profiles, but exciting results are also expected from line profile measurements of individual line emitting objects such as supernovae, supernova remnants, and novae.

  3. Real breakthrough in detection of radioactive sources by portal monitors with plastic detectors and New Advanced Source Identification Algorithm (ASIA-New)

    SciTech Connect

    Stavrov, Andrei; Yamamoto, Eugene

    2015-07-01

    Radiation Portal Monitors (RPM) with plastic detectors represent the main instruments used for primary border (customs) radiation control. RPM are widely used because they are simple, reliable, relatively inexpensive and have a high sensitivity. However, experience using the RPM in various countries has revealed the systems have some grave shortcomings. There is a dramatic decrease of the probability of detection of radioactive sources under high suppression of the natural gamma background (radiation control of heavy cargoes, containers and, especially, trains). NORM (Naturally Occurring Radioactive Material) existing in objects under control trigger the so-called 'nuisance alarms', requiring a secondary inspection for source verification. At a number of sites, the rate of such alarms is so high it significantly complicates the work of customs and border officers. This paper presents a brief description of new variant of algorithm ASIA-New (New Advanced Source Identification Algorithm), which was developed by the Rapiscan company. It also demonstrates results of different tests and the capability of a new system to overcome the shortcomings stated above. New electronics and ASIA-New enables RPM to detect radioactive sources under a high background suppression (tested at 15-30%) and to verify the detected NORM (KCl) and the artificial isotopes (Co- 57, Ba-133 and other). New variant of ASIA is based on physical principles, a phenomenological approach and analysis of some important parameter changes during the vehicle passage through the monitor control area. Thanks to this capability main advantage of new system is that this system can be easily installed into any RPM with plastic detectors. Taking into account that more than 4000 RPM has been installed worldwide their upgrading by ASIA-New may significantly increase probability of detection and verification of radioactive sources even masked by NORM. This algorithm was tested for 1,395 passages of different

  4. Transuranium isotopes

    SciTech Connect

    Hoffman, D.C.

    1985-12-01

    The needs of the research community for the production of transuranium isotopes, the quantities required, the continuity of production desired, and what a new steady state neutron source would have to provide to satisfy these needs are discussed. Examples of past frontier research which need these isotopes as well as an outline of the proposed Large Einsteinium Activation Program, LEAP, which requires roughly ten times the current production of /sup 254/Es are given. 15 refs., 5 figs., 4 tabs.

  5. Isotopic Paleoclimatology

    NASA Astrophysics Data System (ADS)

    Bowen, R.

    Paleotemperature scales were calculated by H. C. Urey and others in the 1950s to assess past temperatures, and later work using the stable isotopes of oxygen, hydrogen, and carbon employed standards such as Peedee belemnite (PDB) and Standard Mean Ocean Water (SMOW). Subsequently, subjects as diverse as ice volume and paleotemperatures, oceanic ice and sediment cores, Pleistocene/Holocene climatic changes, and isotope chronostratigraphy extending back to the Precambrian were investigated.

  6. Isotopic chirality

    SciTech Connect

    Floss, H.G.

    1994-12-01

    This paper deals with compounds that are chiral-at least in part, due to isotope substitution-and their use in tracing the steric course of enzyme reaction in vitro and in vivo. There are other applications of isotopically chiral compounds (for example, in analyzing the steric course of nonenzymatic reactions and in probing the conformation of biomolecules) that are important but they will not be discussed in this context.

  7. Radioactivity in municipal sludge

    SciTech Connect

    Brennan, M.J.; Erickson, J.L.; Albin, C.L.M.

    1996-06-01

    Over the last 9 years the Department of Health has sampled Waste Water Treatment Plant Biosolid Material (Sludge) a total of 11 times at 6 treatment plants. The majority of the samples were collected in 1994 in a campaign designed to learn what radioisotopes where entering sewer Systems in the State, what sludge disposal methods were and are being used, and whether the radionuclides were causing a public health effect. The samples were analyzed using standard laboratory procedures. Most of the man-made isotopes appear to be fallout or medical in origin, but there were some surprises. To determine if the radionuclides present a public health hazard, the measured concentrations were modeled, using several standardized scenarios. All calculations were done using the RESRAD computer code. A number of questions arose concerning the sources of some of the isotopes and how best to include the naturally occurring radionuclides in the dose calculations.

  8. Direct reaction experimental studies with beams of radioactive tin ions

    SciTech Connect

    Jones, K. L. Ayres, A.; Bey, A.; Burcher, S.; Cartegni, L.; Cerizza, G.; Ahn, S.; Allmond, J. M.; Beene, J. R.; Galindo-Uribarri, A.; Liang, J. F.; Nesaraja, C. D.; Pain, S. D.; Radford, D. C.; Schmitt, K. T.; Smith, M. S.; Stracener, D. W.; Varner, R. L.; Bardayan, D. W.; Baugher, T.; and others

    2015-10-15

    The tin chain of isotopes provides a unique region in which to investigate the evolution of single-particle structure, spreading from N = 50 at {sup 100}Sn, through 10 stable isotopes and the N = 82 shell closure at {sup 132}Sn out into the r-process path. Direct reactions performed on radioactive ion beams are sensitive spectroscopic tools for studying exotic nuclei. Here we present one experiment knocking out neutrons from tin isotopes that are already neutron deficient and two reactions that add a neutron to neutron-rich {sup 130}Sn. Both techniques rely on selective particle identification and the measurement of γ rays in coincidence with charged ions. We present the goals of the two experiments and the particle identification for the channels of interest. The final results will be presented in future publications.

  9. Direct Reaction Experimental Studies with Beams of Radioactive Tin Ions

    SciTech Connect

    Jones, K. L.; Ahn, S.H.; Allmond, James M; Ayres, A.; Bardayan, Daniel W; Baugher, T.; Bazin, D.; Beene, James R; Berryman, J. S.; Bey, A.; Bingham, C. R.; Cartegni, L.; Chae, K. Y.; Gade, A.; Galindo-Uribarri, Alfredo {nmn}; Garcia-Ruiz, R.F.; Grzywacz, Robert Kazimierz; Howard, Meredith E; Kozub, R. L.; Liang, J Felix; Manning, Brett M; Matos, M.; McDaniel, S.; Miller, D.; Nesaraja, Caroline D; O'Malley, Patrick; Padgett, S; Padilla-Rodal, Elizabeth; Pain, Steven D; Pittman, S. T.; Radford, David C; Ratkiewicz, Andrew J; Schmitt, Kyle; Smith, Michael Scott; Stracener, Daniel W; Stroberg, S.; Tostevin, Jeffrey A; Varner Jr, Robert L; Weisshaar, D.; Wimmer, K.

    2015-01-01

    The tin chain of isotopes provides a unique region in which to investigate the evolution of single-particle structure, spreading from N = 50 at Sn-100, through 10 stable isotopes and the N = 82 shell closure at Sn-132 out into the r-process path. Direct reactions performed on radioactive ion beams are sensitive spectroscopic tools for studying exotic nuclei. Here we present one experiment knocking out neutrons from tin isotopes that are already neutron deficient and two reactions that add a neutron to neutron-rich Sn-130. Both techniques rely on selective particle identification and the measurement of gamma rays in coincidence with charged ions. We present the goals of the two experiments and the particle identification for the channels of interest. The final results will be presented in future publications.

  10. Artificial Respiration and Artificial Circulation

    PubMed Central

    Brook, Joseph; Brook, Morris H.; Lopez, Jose F.

    1965-01-01

    A training program in the newer methods of treatment of acute cardiopulmonary emergencies which was developed at the University Hospital, University of Saskatchewan, is reported. Artificial respiration by the chance rescuer, primary and secondary resuscitation, and post-resuscitation measures involving the use of special drugs and equipment by trained personnel are described. Figures and tables designed for wall-mounting and ready reference in an emergency situation are presented. Firstaid ventilatory adjuncts for use by trained personnel are classified and critically appraised, and the propriety of their use is emphasized. A plea is made to the medical profession and allied agencies to assume the responsibility of spreading knowledge of the new techniques more widely. Unless effective treatment is instituted early enough to prevent death or permanent anoxic damage to heart and brain, follow-through therapy will often be fruitless. PMID:14339303

  11. Isotope distribution program at the Oak Ridge National Laboratory with emphasis on medical isotopes

    SciTech Connect

    Adair, H.L.

    1987-02-26

    The Isotope Distribution Program (IDP) is a group of individual activities with separate and diverse DOE sponsors which share the common mission of the production and distribution of isotope products and the performance of isotope-related services. Its basic mission is to provide isotope products and associated services to the user community by utilizing government-owned facilities that are excess to the primary mission of the DOE. The IDP is in its 41st year of operation. Initially, the program provided research quantities of radioactive materials, and through the 1950's it was the major supplier of radioisotopes for both research and commercial application. Distribution of enriched stable isotopes began in 1954. This paper discusses the use of radioisotopes in medicine and the role that ORNL plays in this field.

  12. DISSOLVED CONCENTRATION LIMITS OF RADIOACTIVE ELEMENTS

    SciTech Connect

    P. Bernot

    2005-07-13

    The purpose of this study is to evaluate dissolved concentration limits (also referred to as solubility limits) of elements with radioactive isotopes under probable repository conditions, based on geochemical modeling calculations using geochemical modeling tools, thermodynamic databases, field measurements, and laboratory experiments. The scope of this activity is to predict dissolved concentrations or solubility limits for elements with radioactive isotopes (actinium, americium, carbon, cesium, iodine, lead, neptunium, plutonium, protactinium, radium, strontium, technetium, thorium, and uranium) relevant to calculated dose. Model outputs for uranium, plutonium, neptunium, thorium, americium, and protactinium are provided in the form of tabulated functions with pH and log fCO{sub 2} as independent variables, plus one or more uncertainty terms. The solubility limits for the remaining elements are either in the form of distributions or single values. Even though selection of an appropriate set of radionuclides documented in Radionuclide Screening (BSC 2002 [DIRS 160059]) includes actinium, transport of Ac is not modeled in the total system performance assessment for the license application (TSPA-LA) model because of its extremely short half-life. Actinium dose is calculated in the TSPA-LA by assuming secular equilibrium with {sup 231}Pa (Section 6.10); therefore, Ac is not analyzed in this report. The output data from this report are fundamental inputs for TSPA-LA used to determine the estimated release of these elements from waste packages and the engineered barrier system. Consistent modeling approaches and environmental conditions were used to develop solubility models for the actinides discussed in this report. These models cover broad ranges of environmental conditions so they are applicable to both waste packages and the invert. Uncertainties from thermodynamic data, water chemistry, temperature variation, and activity coefficients have been quantified or

  13. Isotopic signatures by bulk analyses

    SciTech Connect

    Efurd, D.W.; Rokop, D.J.

    1997-12-01

    Los Alamos National Laboratory has developed a series of measurement techniques for identification of nuclear signatures by analyzing bulk samples. Two specific applications for isotopic fingerprinting to identify the origin of anthropogenic radioactivity in bulk samples are presented. The first example is the analyses of environmental samples collected in the US Arctic to determine the impact of dumping of radionuclides in this polar region. Analyses of sediment and biota samples indicate that for the areas sampled the anthropogenic radionuclide content of sediments was predominantly the result of the deposition of global fallout. The anthropogenic radionuclide concentrations in fish, birds and mammals were very low. It can be surmised that marine food chains are presently not significantly affected. The second example is isotopic fingerprinting of water and sediment samples from the Rocky Flats Facility (RFP). The largest source of anthropogenic radioactivity presently affecting surface-waters at RFP is the sediments that are currently residing in the holding ponds. One gram of sediment from a holding pond contains approximately 50 times more plutonium than 1 liter of water from the pond. Essentially 100% of the uranium in Ponds A-1 and A-2 originated as depleted uranium. The largest source of radioactivity in the terminal Ponds A-4, B-5 and C-2 was naturally occurring uranium and its decay product radium. The uranium concentrations in the waters collected from the terminal ponds contained 0.05% or less of the interim standard calculated derived concentration guide for uranium in waters available to the public. All of the radioactivity observed in soil, sediment and water samples collected at RFP was naturally occurring, the result of processes at RFP or the result of global fallout. No extraneous anthropogenic alpha, beta or gamma activities were detected. The plutonium concentrations in Pond C-2 appear to vary seasonally.

  14. Isotopic trace analysis by atomic mass spectrometry

    SciTech Connect

    Stoffels, J.J.

    1993-12-01

    All the production facilities at Hanford are now shut down. However, the legacy from half a century of plutonium production includes 177 underground storage tanks of up to one million gallons each containing the largest accumulation of high-level radioactive waste in what used to be called ``the free world.`` Hanford`s new mission, in addition to a spectrum of ongoing research and development, is radioactive waste management and environmental restoration. Isotope-ratio mass spectrometry will continue to be an essential tool in monitoring the progress of that mission.

  15. Radioactive pollution in Athens, Greece due to the Fukushima nuclear accident.

    PubMed

    Kritidis, P; Florou, H; Eleftheriadis, K; Evangeliou, N; Gini, M; Sotiropoulou, M; Diapouli, E; Vratolis, S

    2012-12-01

    As a result of the nuclear accident in Fukushima Dai-ichi power plant, which started on March 11, 2011, radioactive pollutants were transferred by air masses to various regions of the Northern hemisphere, including Europe. Very low concentrations of (131)I, (137)Cs and (134)Cs in airborne particulate matter were measured in Athens, Greece during the period of March 24 to April 28, 2011. The maximum air concentration of (131)I was measured on April 6, 2011 and equaled 490 ± 35 μBq m(-3). The maximum values of the two cesium isotopes were measured on the same day and equaled 180 ± 40 μBq m(-3) for (137)Cs and 160 ± 30 μBq m(-3) for (134)Cs. The average activity ratio of (131)I/(137)Cs in air was 3.0 ± 0.5, while the corresponding ratio of (137)Cs/(134)Cs equaled 1.1 ± 0.3. No artificial radionuclides could be detected in air after April 28, 2011. Traces of (131)I as a result of radioactive deposition were measured in grass, soil, sheep milk and meat. The total deposition of (131)I (dry + wet) was 34 ± 4 Bq m(-2), and of (137)Cs was less than 10 Bq m(-2). The maximum concentration of (131)I in grass was 2.1 ± 0.4 Bg kg(-1), while (134)Cs was not detected. The maximum concentrations of (131)I and (137)Cs in sheep milk were 1.7 ± 0.16 Bq kg(-1) and 0.6 ± 0.12 Bq kg(-1) respectively. Concentrations of (131)I up to 1.3 ± 0.2 Bq kg(-1) were measured in sheep meat. Traces of (131)I were found in a number of soil samples. The radiological impact of the Fukushima nuclear accident in Athens region was practically negligible, especially as compared to that of the Chernobyl accident and also to that of natural radioactivity. Copyright © 2011 Elsevier Ltd. All rights reserved.

  16. Radioactive waste processing apparatus

    DOEpatents

    Nelson, Robert E.; Ziegler, Anton A.; Serino, David F.; Basnar, Paul J.

    1987-01-01

    Apparatus for use in processing radioactive waste materials for shipment and storage in solid form in a container is disclosed. The container includes a top, and an opening in the top which is smaller than the outer circumference of the container. The apparatus includes an enclosure into which the container is placed, solution feed apparatus for adding a solution containing radioactive waste materials into the container through the container opening, and at least one rotatable blade for blending the solution with a fixing agent such as cement or the like as the solution is added into the container. The blade is constructed so that it can pass through the opening in the top of the container. The rotational axis of the blade is displaced from the center of the blade so that after the blade passes through the opening, the blade and container can be adjusted so that one edge of the blade is adjacent the cylindrical wall of the container, to insure thorough mixing. When the blade is inside the container, a substantially sealed chamber is formed to contain vapors created by the chemical action of the waste solution and fixant, and vapors emanating through the opening in the container.

  17. Radioactivities induced in some LDEF samples

    NASA Technical Reports Server (NTRS)

    Reedy, Robert C.; Moss, Calvin E.; Bobias, S. George; Masarik, Jozef

    1993-01-01

    Radioactivities induced in several Long Duration Exposure Facilities (LDEF) samples were measured by low-level counting at Los Alamos and elsewhere. These radionuclides have activities similar to those observed in meteorites and lunar samples. Some trends were observed in these measurements in terms of profiles in trunnion layers and as a function of radionuclide half-life. Several existing computer codes were used to model the production by the protons trapped in the Earth's radiation belts and by the galactic cosmic rays of some of these radionuclides, Mn-54 and Co-57 in steel, Sc-46 in titanium, and Na-22 in alloys of titanium and aluminum. Production rates were also calculated for radionuclides possibly implanted in LDEF, Be-7, Be-10, and C-14. Enhanced concentrations of induced isotopes in the surfaces of trunnion sections relative to their concentrations in the center are caused by the lower-energy protons in the trapped radiation. Secondary neutrons made by high-energy trapped protons and by galactic cosmic rays produce much of the observed radioactivities, especially deep in an object. Comparisons of the observed to calculated activities of several radionuclides with different half-lives indicate that the flux of trapped protons at LDEF decreased significantly at the end of the mission.

  18. Fred Hoyle, primary nucleosynthesis and radioactivity

    NASA Astrophysics Data System (ADS)

    Clayton, Donald D.

    2008-10-01

    Primary nucleosynthesis is defined as that which occurs efficiently in stars born of only H and He. It is responsible not only for increasing the metallicity of the galaxy but also for the most abundant gamma-ray-line emitters. Astrophysicists have inappropriately cited early work in this regard. The heavily cited B2FH paper (Burbidge et al., 1957) did not effectively address primary nucleosynthesis whereas Hoyle (Hoyle, 1954) had done so quite thoroughly in his infrequently cited 1954 paper. Even B2FH with Hoyle as coauthor seems strangely to not have appreciated what Hoyle (Hoyle, 1954) had achieved. I speculate that Hoyle must not have thoroughly proofread the draft written in 1956 by E.M. and G.R. Burbidge. The clear roadmap of primary nucleosynthesis advanced in 1954 by Hoyle describes the synthesis yielding the most abundant of the radioactive isotopes for astronomy, although that aspect was unrealized at the time. Secondary nucleosynthesis has also produced many observable radioactive nuclei, including the first gamma-ray-line emitter to be discovered in the galaxy and several others within stardust grains. Primary gamma-ray emitters would have been even more detectable in the early galaxy, when the birth rate of massive stars was greater; but secondary emitters, such as 26Al, would have been produced with smaller yield then owing to smaller abundance of seed nuclei from which to create them.

  19. Coulomb excitation of radioactive {sup 79}Pb

    SciTech Connect

    Lister, C.J.; Blumenthal, D.; Davids, C.N.

    1995-08-01

    The technical challenges expected in experiments with radioactive beams can already be explored by using ions produced in primary reactions. In addition, the re-excitation of these ions by Coulomb excitation allows a sensitive search for collective states that are well above the yrast line. We are building an experiment to study Coulomb excitation of radioactive ions which are separated from beam particles by the Fragment Mass Analyzer. An array of gamma detectors will be mounted at the focal plane to measure the gamma radiation following re-excitation. Five Compton-suppressed Ge detectors and five planar LEPS detectors will be used. The optimum experiment of this type appears to be the study of {sup 79}Rb following the {sup 24}Mg ({sup 58}Ni,3p) reaction. We calculate that about 5 x 10{sup 5} {sup 79}Rb nuclei/second will reach the excitation foil. This rubidium isotope was selected for study as it is strongly produced and is highly deformed, so easily re-excited. The use of a {sup 58}Ni re-excitation foil offers the best yields. After re-excitation the ions will be subsequently transported into a shielded beamdump to prevent the accumulation of activity.

  20. Artificial gametes.

    PubMed

    Nagy, Zsolt Peter; Chang, Ching-Chien

    2007-01-01

    In vitro fertilization (IVF) has been an efficient medical treatment for infertility in the past decades. However, conventional IVF approaches may be insufficient when gametes are lacking or non-viable thus precluding a significant number of patients from treatment. Ultimately, creation of artificial gametes may provide an universal solution for all indications. Somatic cell nuclear transfer (SCNT) has provided successful cloning in different animal species indicating that a derived technology may be applicable in infertility treatment procedures. Attempts to produce functional male or female gamete through nuclear transfer have been described through the process called haploidization. Initial successes have been observed, however, significant alterations at spindle construction and chromosomal segregation were also described. Stem cell technology may provide an alternative route to obtain fully functional gametes. Both sperm cells and oocytes were obtained using specific culture conditions for embryo originated stem cell. These two mainstream approaches are presented in the current review. Both of these techniques are involving sophisticated methods and consequently both of them demonstrate technical and ethical challenges. Related questions on (mitotic/meiotic) cell division, genetic/epigenetic alterations and cell renewal are needed to be addressed before clinical application.

  1. IUPAC Periodic Table of Isotopes for the Educational Community

    SciTech Connect

    Holden N. E.; Holden,N.E.; Coplen,T.B.

    2012-07-15

    John Dalton first proposed the concept of atomic weights of the elements in the first decade of the nineteenth century. These atomic weights of the chemical elements were thought of as constants of nature, similar to the speed of light. Dmitri Mendeleev arranged the atomic weights of the elements in ascending order of value and used the systematic variation of their chemical properties to produce his Periodic Table of the Elements in 1869. Measurement of atomic weight values became an important chemical activity for a century and a half. Theodore Richards received a Noble Prize for his work in this area. In 1913, Fredrick Soddy found a species of radium, which had an atomic weight value of 228, compared to the familiar radium gas value of 226. Soddy coined the term 'isotope' (Greek for 'in the same place') to account for this second atomic weight value in the radium position of the Periodic Table. Both of these isotopes of radium are radioactive. Radioactive isotopes are energetically unstable and will decay (disintegrate) over time. The time it takes for one half of a sample of a given radioactive isotope to decay is the half-life of that isotope. In addition to having different atomic weight values, radium-226 and radium-228 also have different half-life values. Around the same time as Soddy's work, J.J. Thomson (discoverer of the electron) identified two stable (non-radioactive) isotopes of the same element, neon. Over the next 40 years, the majority of the known chemical elements were found to have two or more stable (or long-lived radioactive isotopes that contribute significantly to the determination of the atomic weights of the elements).

  2. Stefan Meyer: Pioneer of Radioactivity

    NASA Astrophysics Data System (ADS)

    Reiter, Wolfgang L.

    2001-03-01

    Stefan Meyer was one of the pioneers in radioactivity research and director of the Vienna Radium Institute, the first institution in the world devoted exclusively to radioactivity. I give here a biographical sketch of Meyer and of some of his colleagues and an overview of the research activities at the Radium Institute.

  3. Understanding radioactive waste. Fourth edition

    SciTech Connect

    Murray, R.L.

    1994-12-31

    Understanding Radioactive Waste has proven to be an informative and valuable textbook for high school and college students as well as an excellent reference for concerned citizens. Now in its fourth edition, it explains what radioactivity is and goes on to explore the merits of various methods of disposal and the use of licensing and regulation as forms of protection.

  4. Radioactive elements in stellar atmospheres

    SciTech Connect

    Gopka, Vira; Yushchenko, Alexander; Goriely, Stephane; Shavrina, Angelina; Kang, Young Woon

    2006-07-12

    The identification of lines of radioactive elements (Tc, Pm and elements with 83radioactive decay of Th and U in the upper levels of stellar atmospheres, contamination of stellar atmosphere by recent SN explosion, and spallation reactions.

  5. Coulomb Excitation of Radioactive Mo-Ru Isotopes

    NASA Astrophysics Data System (ADS)

    Allmond, J. M.; Gretina-Chico2 Collaboration

    2016-09-01

    The study of shapes in atomic nuclei has been a major focus of nuclear structure ever since the observation of large electric quadrupole moments in the first half of the 20th century. A leading challenge has been to experimentally establish regions of oblate deformation, which are very limited, and triaxial deformation. The neutron-rich Mo-Ru region is expected to exhibit triaxial deformation in the low-lying states, mediated by a relatively rare instance of prolate-to-oblate shape evolution. A survey of equipment, techniques, and preliminary results from recent Coulomb-excitation and beta-decay experiments in the neutron-rich Mo-Ru region will be presented. These experiments were conducted at the CARIBU-ANL facility using GRETINA-CHICO2. An emphasis will be placed on unique opportunities with 3-MeV/u beams. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Nuclear Physics.

  6. The Safe use of Radioactive Isotopes in Teaching Experiments

    ERIC Educational Resources Information Center

    Hawcroft, D. M.; Stewart, J. C.

    1974-01-01

    This article briefly discusses some of the dangers involved in the use of radioisotopes and includes a comprehensive list of precautions and laboratory rules for use during radiobiology experiments. (Author)

  7. The Safe use of Radioactive Isotopes in Teaching Experiments

    ERIC Educational Resources Information Center

    Hawcroft, D. M.; Stewart, J. C.

    1974-01-01

    This article briefly discusses some of the dangers involved in the use of radioisotopes and includes a comprehensive list of precautions and laboratory rules for use during radiobiology experiments. (Author)

  8. [Possibility of pulmonary circulation study with nongaseous radioactive isotopes].

    PubMed

    Carratu', L

    1978-12-01

    This paper deales with the applications of radionuclides to the study of human pulmonary circulation for better knowledge of some morphological and dinamic functional aspects. At this time the methods used are divided in three groups in respect to the purpose. - Methods for static investigations of pulmonary perfusion, by scintigraphy with radioalbum aggregates. - Methods for dynamic investigation, general radiocardiography and selective right radiocardiography with radioalbum macroaggregates. - Methods for morpho-functional investigation, especially Isotopoangiocardiopneumography using gamma-camera and Tc99mO4. Here are treated the fields of applications, the purpose and the limits of these methods, used in a large number of and acquired pulmonary vascular diseases.

  9. Low Radioactivity in CANDLES

    SciTech Connect

    Kishimoto, T.; Ogawa, I.; Hazama, R.; Yoshida, S.; Umehara, S.; Matsuoka, K.; Sakai, H.; Yokoyama, D.; Mukaida, K.; Ichihara, K.; Tatewaki, Y.; Kishimoto, K.; Hirano, Y.; Yanagisawa, A.; Ajimura, S.

    2005-09-08

    CANDLES is the project to search for double beta decay of 48Ca by using CaF2 crystals. Double beta decay of 48Ca has the highest Q value among all nuclei whose double beta decay is energetically allowed. This feature makes the study almost background free and becomes important once the study is limited by the backgrounds. We studied double beta decays of 48Ca by using ELEGANTS VI detector system which features CaF2(Eu) crystals. We gave the best limit on the lifetime of neutrino-less double beta decay of 48Ca although further development is vital to reach the neutrino mass of current interest for which CANDLES is designed. In this article we present how CANDLES can achieve low radioactivity, which is the key for the future double beta decay experiment.

  10. Arduino based radioactive tracking system

    NASA Astrophysics Data System (ADS)

    Rahman, Nur Aira Abd; Rashid, Mohd Fazlie Bin Abdul; Rahman, Anwar Bin Abdul; Ramlan, Atikah

    2017-01-01

    There is a clear need to strengthen security measures to prevent any malevolent use or accidental misuse of radioactive sources. Some of these radioactive sources are regularly transported outside of office or laboratory premises for work and consultation purposes. This paper present the initial development of radioactive source tracking system, which combined Arduino microcontroller, Global Positioning System (GPS) and Global System for Mobile communication (GSM) technologies. The tracking system will help the owner to monitor the movement of the radioactive sources. Currently, the system is capable of tracking the movement of radioactive source through the GPS satellite signals. The GPS co-ordinate could either be transmitted to headquarters at fixed interval via Short Messaging Service (SMS) to enable real time monitoring, or stored in a memory card for offline monitoring and data logging.

  11. Radioactive waste processing apparatus

    DOEpatents

    Nelson, R.E.; Ziegler, A.A.; Serino, D.F.; Basnar, P.J.

    1985-08-30

    Apparatus for use in processing radioactive waste materials for shipment and storage in solid form in a container is disclosed. The container includes a top, and an opening in the top which is smaller than the outer circumference of the container. The apparatus includes an enclosure into which the container is placed, solution feed apparatus for adding a solution containing radioactive waste materials into the container through the container opening, and at least one rotatable blade for blending the solution with a fixing agent such as cement or the like as the solution is added into the container. The blade is constructed so that it can pass through the opening in the top of the container. The rotational axis of the blade is displaced from the center of the blade so that after the blade passes through the opening, the blade and container can be adjusted so that one edge of the blade is adjacent the cylindrical wall of the container, to insure thorough mixing. When the blade is inside the container, a substantially sealed chamber is formed to contain vapors created by the chemical action of the waste solution and fixant, and vapors emanating through the opening in the container. The chamber may be formed by placing a removable extension over the top of the container. The extension communicates with the apparatus so that such vapors are contained within the container, extension and solution feed apparatus. A portion of the chamber includes coolant which condenses the vapors. The resulting condensate is returned to the container by the force of gravity.

  12. The isotopic composition of cosmic ray chlorine

    NASA Technical Reports Server (NTRS)

    Wiedenbeck, M. E.

    1985-01-01

    The isotopic composition of galactic cosmic ray chlorine (approx. = 225 MeV/amu) has been studied using the high energy cosmic ray experiment on the International Sun Earth Explorer 3 (ISEE-3) spacecraft. The abundances of 35C1 and 37C1 are found to be consistent with the secondary production expected from a propagation model developed to account for both light and subiron secondaries. An upper limit on the abundance of the radioactive isotope 36C1 (halflife approx. = 0.3 Myr) is used to set a lower limit on the confinement time of cosmic rays of approximately 1 Myr.

  13. Isotope Tracers To Study the Environmental Fate and Bioaccumulation of Metal-Containing Engineered Nanoparticles: Techniques and Applications.

    PubMed

    Yin, Yongguang; Tan, Zhiqiang; Hu, Ligang; Yu, Sujuan; Liu, Jingfu; Jiang, Guibin

    2017-03-08

    The rapidly growing applicability of metal-containing engineered nanoparticles (MENPs) has made their environmental fate, biouptake, and transformation important research topics. However, considering the relatively low concentration of MENPs and the high concentration of background metals in the environment and in organisms, tracking the fate of MENPs in environment-related scenarios remains a challenge. Intrinsic labeling of MENPs with radioactive or stable isotopes is a useful tool for the highly sensitive and selective detection of MENPs in the environment and organisms, thus enabling tracing of their transformation, uptake, distribution, and clearance. In this review, we focus on radioactive/stable isotope labeling of MENPs for their environmental and biological tracing. We summarize the advantages of intrinsic radioactive/stable isotopes for MENP labeling and discuss the considerations in labeling isotope selection and preparation of labeled MENPs, as well as exposure routes and detection of labeled MENPs. In addition, current practice in the use of radioactive/stable isotope labeling of MENPs to study their environmental fate and bioaccumulation is reviewed. Future perspectives and potential applications are also discussed, including imaging techniques for radioactive- and stable-isotope-labeled MENPs, hyphenated multistable isotope tracers with speciation analysis, and isotope fractionation as a MENP tracer. It is expected that this critical review could provide the necessary background information to further advance the applications of isotope tracers to study the environmental fate and bioaccumulation of MENPs.

  14. ISOTOPE SEPARATORS

    DOEpatents

    Bacon, C.G.

    1958-08-26

    An improvement is presented in the structure of an isotope separation apparatus and, in particular, is concerned with a magnetically operated shutter associated with a window which is provided for the purpose of enabling the operator to view the processes going on within the interior of the apparatus. The shutier is mounted to close under the force of gravity in the absence of any other force. By closing an electrical circuit to a coil mouated on the shutter the magnetic field of the isotope separating apparatus coacts with the magnetic field of the coil to force the shutter to the open position.

  15. Radioactive check sources for alpha and beta sensitive radiological instrumentation

    SciTech Connect

    Barnett, J.M.; Kane, J.E. II

    1994-06-01

    Since 1991, the Westinghouse Hanford Company has examined the construction and use of alpha and beta radioactive check sources for calibrating instruments and for performing response checks of instruments used for operational and environmental radiation detection. The purpose of using a radioactive check source is to characterize the response of a radiation monitoring instrument in the presence of radioactivity. To accurately calibrate the instrument and check its response, the check source used must emulate as closely as possible the actual physical and isotopic conditions being monitored. The isotope employed and the physical methods used to fabricate the check source (among other factors) determine instrument response. Although information from applicable national and international standards, journal articles, books, and government documents was considered, empirical data collected is most valuable when considering the type of source to use for a particular application. This paper presents source construction methods, use considerations, and standard recommendations. The results of a Hanford Site evaluation of several types of alpha and beta sources are also given.

  16. The SPES Radioactive Ion Beam facility of INFN

    NASA Astrophysics Data System (ADS)

    de Angelis, G.; Spes Collaboration; Prete, G.; Andrighetto, A.; Manzolaro, M.; Corradetti, S.; Scarpa, D.; Rossignoli, M.; Monetti, A.; Lollo, M.; Calderolla, M.; Vasquez, J.; Zafiropoulos, D.; Sarchiapone, L.; Benini, D.; Favaron, P.; Rigato, M.; Pegoraro, R.; Maniero, D.; Calabretta, L.; Comunian, M.; Maggiore, M.; Lombardi, A.; Piazza, L.; Porcellato, A. M.; Roncolato, C.; Bisoffi, G.; Pisent, A.; Galatà, A.; Giacchini, M.; Bassato, G.; Canella, S.; Gramegna, F.; Valiente, J.; Bermudez, J.; Mastinu, P. F.; Esposito, J.; Wyss, J.; Russo, A.; Zanella, S.

    2015-02-01

    A new Radioactive Ion Beam (RIB) facility (SPES) is presently under construction at the Legnaro National Laboratories of INFN. The SPES facility is based on the ISOL method using an UCx Direct Target able to sustain a power of 10 kW. The primary proton beam is provided by a high current Cyclotron accelerator with energy of 40 MeV and a beam current of 0.2-0.5 mA. Neutron-rich radioactive ions are produced by proton induced fission at an expected fission rate of the order of 1013 fissions per second. After ionization and selection the exotic isotopes are re-accelerated by the ALPI superconducting LINAC at energies of 10A MeV for masses in the region A=130 amu. The expected secondary beam rates are of the order of 107 - 109 pps. Aim of the SPES facility is to deliver high intensity radioactive ion beams of neutron rich nuclei for nuclear physics research as well as to be an interdisciplinary research center for radio-isotopes production for medicine and for neutron beams.

  17. The SPES radioactive ion beam project of INFN

    NASA Astrophysics Data System (ADS)

    de Angelis, Giacomo; Spes Collaboration; Prete, G.; Andrighetto, A.; Manzolaro, M.; Corradetti, S.; Scarpa, D.; Rossignoli, M.; Monetti, A.; Lollo, M.; Calderolla, M.; Vasquez, J.; Zafiropoulos, D.; Sarchiapone, L.; Benini, D.; Favaron, P.; Rigato, M.; Pegoraro, R.; Maniero, D.; Calabretta, L.; Comunian, M.; Maggiore, M.; Lombardi, A.; Piazza, L.; Porcellato, A. M.; Roncolato, C.; Bisoffi, G.; Pisent, A.; Galatà, A.; Giacchini, M.; Bassato, G.; Canella, S.; Gramegna, F.; Valiente, J.; Bermudez, J.; Mastinu, P. F.; Esposito, J.; Wyss, J.; Russo, A.; Zanella, S.

    2014-07-01

    The SPES Radioactive Ion Beam facility at INFN-LNL is presently in the construction phase. The facility is based on the Isol (Isotope separation on-line) method with an UCx Direct Target able to sustain a power of 10 kW. The primary proton beam is provided by a high current Cyclotron accelerator with energy of 35-70 MeV and a beam current of 0.20.5 mA. Neutron-rich radioactive ions are produced by proton induced Uranium fission at an expected fission rate of the order of 1013 fissions per second. After ionization and selection the exotic isotopes are re-accelerated by the ALPI superconducting Linac at energies of 10A MeV for masses in the region A = 130 amu. The expected secondary beam rates are of the order of 107 - 109 pps. Aim of the SPES project is to provide a facility for high intensity radioactive ion beams for nuclear physics research as well as to develop an interdisciplinary research center based on the cyclotron proton beam.

  18. Environmental radioactive intercomparison program and radioactive standards program

    SciTech Connect

    Dilbeck, G.

    1993-12-31

    The Environmental Radioactivity Intercomparison Program described herein provides quality assurance support for laboratories involved in analyzing public drinking water under the Safe Drinking Water Act (SDWA) Regulations, and to the environmental radiation monitoring activities of various agencies. More than 300 federal and state nuclear facilities and private laboratories participate in some phase of the program. This presentation describes the Intercomparison Program studies and matrices involved, summarizes the precision and accuracy requirements of various radioactive analytes, and describes the traceability determinations involved with radioactive calibration standards distributed to the participants. A summary of program participants, sample and report distributions, and additional responsibilities of this program are discussed.

  19. The isotopic characterization of carbon monoxide in the troposphere

    NASA Astrophysics Data System (ADS)

    Conny, Joseph M.

    The distributions of stable isotopes in trace atmospheric species are controlled mainly by the isotopic compositions of precursor molecules and isotope fractionation effects during production and removal of the species. Distributions of radioactive isotopes are controlled mainly by the isotopic compositions of precursor molecules and radioactive decay processes. As a result, through their isotopic compositions, atmospheric species are traceable to sources and sinks. Thus, isotopic compositions provide useful information for estimating source strengths and for understanding the importance of removal processes in the cycling of the species. The use of radioactive 14C and the stable isotopes ( 13C and 18O) are reviewed here for understanding production and removal processes of CO in the troposphere. Carbon monoxide is a critical component in atmospheric chemistry because of its large effect on levels of OH, the principal oxidant in the atmosphere. In the troposphere, this is due to relatively high concentrations of CO and a short lifetime (2-4 months). Initially, 14CO measurements were instrumental in estimating accurately the tropospheric lifetime. Since seasonal 14CO variation is controlled largely by OH, 14CO serves as an important surrogate measure of tropospheric OH. Global 14CO measurements have also been used to estimate the biogenic component of the global CO budget, specifically contributions from biomass burning, oxidized non-methane hydrocarbon (NMHC) emissions, oceans and plants. Research using 14CO measurements is also active in quantifying fossil and non-fossil urban emissions. Kinetic isotopic fractionation during production of 13CO and C 18O from reduced precursors allows one to distinguish, at least qualitatively, different varieties of CO based on seasonal tropospheric isotopic measurements. Difficulties in interpreting the stable isotopic record arise from large fractionation effects that obscure source isotopic signatures (in particular the oxygen

  20. Stable isotope deltas: tiny, yet robust signatures in nature.

    PubMed

    Brand, Willi A; Coplen, Tyler B

    2012-09-01

    Although most of them are relatively small, stable isotope deltas of naturally occurring substances are robust and enable workers in anthropology, atmospheric sciences, biology, chemistry, environmental sciences, food and drug authentication, forensic science, geochemistry, geology, oceanography, and paleoclimatology to study a variety of topics. Two fundamental processes explain the stable isotope deltas measured in most terrestrial systems: isotopic fractionation and isotope mixing. Isotopic fractionation is the result of equilibrium or kinetic physicochemical processes that fractionate isotopes because of small differences in physical or chemical properties of molecular species having different isotopes. It is shown that the mixing of radioactive and stable isotope end members can be modelled to provide information on many natural processes, including (14)C abundances in the modern atmosphere and the stable hydrogen and oxygen isotopic compositions of the oceans during glacial and interglacial times. The calculation of mixing fractions using isotope balance equations with isotope deltas can be substantially in error when substances with high concentrations of heavy isotopes (e.g. (13)C, (2)H, and (18)O ) are mixed. In such cases, calculations using mole fractions are preferred as they produce accurate mixing fractions. Isotope deltas are dimensionless quantities. In the International System of Units (SI), these quantities have the unit 1 and the usual list of prefixes is not applicable. To overcome traditional limitations with expressing orders of magnitude differences in isotope deltas, we propose the term urey (symbol Ur), after Harold C. Urey, for the unit 1. In such a manner, an isotope delta value expressed traditionally as-25 per mil can be written as-25 mUr (or-2.5 cUr or-0.25 dUr; the use of any SI prefix is possible). Likewise, very small isotopic differences often expressed in per meg 'units' are easily included (e.g. either+0.015 ‰ or+15 per meg

  1. Stable isotope deltas: Tiny, yet robust signatures in nature

    USGS Publications Warehouse

    Brand, Willi A.; Coplen, Tyler B.

    2012-01-01

    Although most of them are relatively small, stable isotope deltas of naturally occurring substances are robust and enable workers in anthropology, atmospheric sciences, biology, chemistry, environmental sciences, food and drug authentication, forensic science, geochemistry, geology, oceanography, and paleoclimatology to study a variety of topics. Two fundamental processes explain the stable isotope deltas measured in most terrestrial systems: isotopic fractionation and isotope mixing. Isotopic fractionation is the result of equilibrium or kinetic physicochemical processes that fractionate isotopes because of small differences in physical or chemical properties of molecular species having different isotopes. It is shown that the mixing of radioactive and stable isotope end members can be modelled to provide information on many natural processes, including 14C abundances in the modern atmosphere and the stable hydrogen and oxygen isotopic compositions of the oceans during glacial and interglacial times. The calculation of mixing fractions using isotope balance equations with isotope deltas can be substantially in error when substances with high concentrations of heavy isotopes (e.g. 13C, 2H, and 18O ) are mixed. In such cases, calculations using mole fractions are preferred as they produce accurate mixing fractions. Isotope deltas are dimensionless quantities. In the International System of Units (SI), these quantities have the unit 1 and the usual list of prefixes is not applicable. To overcome traditional limitations with expressing orders of magnitude differences in isotope deltas, we propose the term urey (symbol Ur), after Harold C. Urey, for the unit 1. In such a manner, an isotope delta value expressed traditionally as−25 per mil can be written as−25 mUr (or−2.5 cUr or−0.25 dUr; the use of any SI prefix is possible). Likewise, very small isotopic differences often expressed in per meg ‘units’ are easily included (e.g. either+0.015 ‰ or+15 per meg

  2. Radioactive deposits in California

    USGS Publications Warehouse

    Walker, George W.; Lovering, Tom G.

    1954-01-01

    Reconnaissance examination by Government geologists of many areas, mine properties, and prospects in California during the period between 1948 and 1953 has confirmed the presence of radioactive materials in place at more than 40 localities. Abnormal radioactivity at these localities is due to concentrations of primary and secondary uranium minerals, to radon gas, radium (?), and to thorium minerals. Of the known occurrences only three were thought to contain uranium oxide (uranitite or pitchblende), 4 contained uranium-bearing columbate, tantalate, or titanate minerals, 12 contained secondary uranium minerals, such as autunite, carnotite, and torbernite, one contained radon gas, 7 contained thorium minerals, and, at the remaining 16 localities, the source of the anomalous radiation was not positively determined. The occurrences in which uranium oxide has been tentatively identified include the Rathgeb mine (Calaveras County), the Yerih group of claims (San Bernardino County), and the Rainbow claim (Madera County). Occurrences of secondary uranium minerals are largely confined to the arid desert regions of south-eastern California including deposits in San Bernardino, Kern, Inyo, and Imperial Counties. Uranium-bearing columbate, tantalate, or titanate minerals have been reported from pegmatite and granitic rock in southeastern and eastern California. Thorium minerals have been found in vein deposits in eastern San Bernardino County and from pegmatites and granitic rocks in various parts of southeastern California; placer concentrations of thorium minerals are known from nearly all areas in the State that are underlain, in part, by plutonic crystalline rocks. The primary uranium minerals occur principally as minute accessory crystals in pegmatite or granitic rock, or with base-metal sulfide minerals in veins. Thorium minerals also occur as accessory crystals in pegmatite or granitic rock, in placer deposits derived from such rock, and, at Mountain Pass, in veins

  3. Automatic Searching Radioactive Sources by Airborne Radioactive Survey Using Multicopter

    NASA Astrophysics Data System (ADS)

    Rim, H.; Eun, S. B.; Kim, K.; Park, S.; Jung, H. K.

    2015-12-01

    In order to prepare emergency situation lost a dangerous radioelement source in advance and to search a radioactive source automatically, we develop airborne radioelement survey system by multicopter. This multicopter radioelement survey system consists of a small portable customized BGO (Bismuth Germanate Oxide) detector, video recording part, wireless connecting part to ground pilot, GPS, and several equipments for automatic flight. This system is possible to search flight by preprogramed lines. This radioactive detecting system are tested to find intentional hidden source, The performance of detecting a source is well proved with very low flight altitude in spite of depending on the magnitude of radioelement sources. The advantage of multicopter system, one of UAV (Unmanned Aerial Vehicle), is to avoid the potential of close access to a dangerous radioactive source by using fully automatic searching capability. In this paper, we introduce our multicopter system for detecting radioactive source and synthetic case history for demonstrating this system.

  4. USING STABLE ISOTOPES FOR FISH DIETARY ANALYSES: COPING WITH TOO MANY SOURCES

    EPA Science Inventory

    Stable isotope analysis can provide a useful tool for determining time-integrated measures of proportional food source contributions to fish diets. Ratios of stable (non-radioactive) isotopes of common elements (e.g., C,N,S) vary among food sources, and tissues of consumers (e.g...

  5. USING STABLE ISOTOPES FOR FISH DIETARY ANALYSES: COPING WITH TOO MANY SOURCES

    EPA Science Inventory

    Stable isotope analysis can provide a useful tool for determining time-integrated measures of proportional food source contributions to fish diets. Ratios of stable (non-radioactive) isotopes of common elements (e.g., C,N,S) vary among food sources, and tissues of consumers (e.g...

  6. [Application of stable isotopes in the study of whole-body protein metabolism].

    PubMed

    Tian, Ying; Yang, Xiaoguang; Piao, Jianhua

    2007-11-01

    Stable isotopes are non-radioactive, so they are safe and suitable for the study of human nutrition. In this paper, the principle and main methods of stable isotopic technique in the study of whole-body protein metabolism were introduced. Meanwhile, the advantages and disadvantages of different methods were discussed and the splanchnic metabolism of labeled amino acids was analyzed.

  7. SELF SINTERING OF RADIOACTIVE WASTES

    DOEpatents

    McVay, T.N.; Johnson, J.R.; Struxness, E.G.; Morgan, K.Z.

    1959-12-29

    A method is described for disposal of radioactive liquid waste materials. The wastes are mixed with clays and fluxes to form a ceramic slip and disposed in a thermally insulated container in a layer. The temperature of the layer rises due to conversion of the energy of radioactivity to heat boillng off the liquid to fomn a dry mass. The dry mass is then covered with thermal insulation, and the mass is self-sintered into a leach-resistant ceramic cake by further conversion of the energy of radioactivity to heat.

  8. Star formation and extinct radioactivities

    NASA Technical Reports Server (NTRS)

    Cameron, A. G. W.

    1984-01-01

    An assessment is made of the evidence for the existence of now-extinct radioactivities in primitive solar system material, giving attention to implications for the early stages of sun and solar system formation. The characteristics of possible disturbances in dense molecular clouds which can initiate the formation of cloud cores is discussed, with emphasis on these disturbances able to generate fresh radioactivities. A one-solar mass red giant star on the asymptotic giant branch appears to have been the best candidate to account for the short-lived extinct radioactivities in the early solar system.

  9. RADIOACTIVE CONCENTRATOR AND RADIATION SOURCE

    DOEpatents

    Hatch, L.P.

    1959-12-29

    A method is presented for forming a permeable ion exchange bed using Montmorillonite clay to absorb and adsorb radioactive ions from liquid radioactive wastes. A paste is formed of clay, water, and a material that fomns with clay a stable aggregate in the presence of water. The mixture is extruded into a volume of water to form clay rods. The rods may then be used to remove radioactive cations from liquid waste solutions. After use, the rods are removed from the solution and heated to a temperature of 750 to 1000 deg C to fix the ratioactive cations in the clay.

  10. Final disposal of radioactive waste

    NASA Astrophysics Data System (ADS)

    Freiesleben, H.

    2013-06-01

    In this paper the origin and properties of radioactive waste as well as its classification scheme (low-level waste - LLW, intermediate-level waste - ILW, high-level waste - HLW) are presented. The various options for conditioning of waste of different levels of radioactivity are reviewed. The composition, radiotoxicity and reprocessing of spent fuel and their effect on storage and options for final disposal are discussed. The current situation of final waste disposal in a selected number of countries is mentioned. Also, the role of the International Atomic Energy Agency with regard to the development and monitoring of international safety standards for both spent nuclear fuel and radioactive waste management is described.

  11. Method for radioactivity monitoring

    DOEpatents

    Umbarger, C. John; Cowder, Leo R.

    1976-10-26

    The disclosure relates to a method for analyzing uranium and/or thorium contents of liquid effluents preferably utilizing a sample containing counting chamber. Basically, 185.7-keV gamma rays following .sup.235 U alpha decay to .sup.231 Th which indicate .sup.235 U content and a 63-keV gamma ray doublet found in the nucleus of .sup.234 Pa, a granddaughter of .sup.238 U, are monitored and the ratio thereof taken to derive uranium content and isotopic enrichment .sup.235 U/.sup.235 U + .sup.238 U) in the liquid effluent. Thorium content is determined by monitoring the intensity of 238-keV gamma rays from the nucleus of .sup.212 Bi in the decay chain of .sup.232 Th.

  12. Radioactive decay data tables

    SciTech Connect

    Kocher, D.C.

    1981-01-01

    The estimation of radiation dose to man from either external or internal exposure to radionuclides requires a knowledge of the energies and intensities of the atomic and nuclear radiations emitted during the radioactive decay process. The availability of evaluated decay data for the large number of radionuclides of interest is thus of fundamental importance for radiation dosimetry. This handbook contains a compilation of decay data for approximately 500 radionuclides. These data constitute an evaluated data file constructed for use in the radiological assessment activities of the Technology Assessments Section of the Health and Safety Research Division at Oak Ridge National Laboratory. The radionuclides selected for this handbook include those occurring naturally in the environment, those of potential importance in routine or accidental releases from the nuclear fuel cycle, those of current interest in nuclear medicine and fusion reactor technology, and some of those of interest to Committee 2 of the International Commission on Radiological Protection for the estimation of annual limits on intake via inhalation and ingestion for occupationally exposed individuals.

  13. (Immobilization of radioactive wastes)

    SciTech Connect

    Dole, L.R.

    1986-12-18

    The traveler participated as the co-chairman of the France/US Workshop in Cadarache, France, on the immobilization of radioactive wastes in cement-based materials. These meetings and site visits were conducted under the bilateral exchange agreement between the US-DOE and the Commissariate a l'Energie Atomique (CEA-France). Visits in France included the Cadarache, Valduc, Saclay, and Fontenay-aux-Roses Nuclear Research Centers. As a result of these discussions, an exchange of scientists between Saclay and ORNL was proposed. The traveler continued on to the FRG to visit a hazardous waste site remedial action project in Sprendlingen and the nuclear research and production facilities at the Karlsruhe Kernforschungszentrum (KfK) and the Alkem/Nukem/Transnuklear facilities at Hanau. Visits in the FRG were under the bilateral exchange agreement between the US-DOE and the Bundes Ministerium fur Forschung und Technologie (BMFT). The FRG supplied the traveler data on studies of super-compaction volume reduction efficiencies by KfK and Nukem. Also, Transnuklear is considering contributing two of their larger Konrad-certified packages to the MDU studies at ORNL. 1 tab.

  14. High power target approaches for intense radioactive ion beam facilities

    SciTech Connect

    Talbert, W.L. ||; Hodges, T.A.; Hsu, H.; Fikani, M.M.

    1997-02-01

    Development of conceptual approaches for targets to produce intense radioactive ion beams is needed in anticipation of activity for a next-generation, intense ISOL-type radioactive beams facility, strongly recommended in the NSAC 1995 Long Range Plan for Nuclear Science. The production of isotopes in vapor form for subsequent mass separation and acceleration will depend on the ability to control target temperature profiles within the target resulting from interactions of the intense production beams with the target material. A number of earlier studies have identified promising approaches which need, however, to be carefully analyzed for specific target systems. A survey will be made of these earlier concepts employing various cooling techniques, including imposition of thermal barriers between the target materials and cooling systems. Some results of preliminary analyses are summarized. {copyright} {ital 1997 American Institute of Physics.}

  15. PHOTOLYSIS STUDIES UTILIZING RADIOACTIVE TRACERS.

    DTIC Science & Technology

    PHOTOLYSIS, *TRACER STUDIES), (* TRITIATED COMPOUNDS, PHOTOLYSIS), (*GAS CHROMATOGRAPHY, LABELED SUBSTANCES), ALKENES, KETENES, TRITIUM, ATOMIC ENERGY LEVELS, ALKANES, METHANE , ISOTOPES, ETHYLENES, MOLECULAR ORBITALS

  16. Consumer Products Containing Radioactive Materials

    MedlinePlus

    ... meter. photo courtesy of Oak Ridge Associated Universities Granite Countertops Granite can release the radioactive gas radon into the ... released can vary considerably from one type of granite to another, the radon concen- trations in most ...

  17. Radioactive waste material melter apparatus

    DOEpatents

    Newman, D.F.; Ross, W.A.

    1990-04-24

    An apparatus for preparing metallic radioactive waste material for storage is disclosed. The radioactive waste material is placed in a radiation shielded enclosure. The waste material is then melted with a plasma torch and cast into a plurality of successive horizontal layers in a mold to form a radioactive ingot in the shape of a spent nuclear fuel rod storage canister. The apparatus comprises a radiation shielded enclosure having an opening adapted for receiving a conventional transfer cask within which radioactive waste material is transferred to the apparatus. A plasma torch is mounted within the enclosure. A mold is also received within the enclosure for receiving the melted waste material and cooling it to form an ingot. The enclosure is preferably constructed in at least two parts to enable easy transport of the apparatus from one nuclear site to another. 8 figs.

  18. Radioactive waste material melter apparatus

    DOEpatents

    Newman, Darrell F.; Ross, Wayne A.

    1990-01-01

    An apparatus for preparing metallic radioactive waste material for storage is disclosed. The radioactive waste material is placed in a radiation shielded enclosure. The waste material is then melted with a plasma torch and cast into a plurality of successive horizontal layers in a mold to form a radioactive ingot in the shape of a spent nuclear fuel rod storage canister. The apparatus comprises a radiation shielded enclosure having an opening adapted for receiving a conventional transfer cask within which radioactive waste material is transferred to the apparatus. A plasma torch is mounted within the enclosure. A mold is also received within the enclosure for receiving the melted waste material and cooling it to form an ingot. The enclosure is preferably constructed in at least two parts to enable easy transport of the apparatus from one nuclear site to another.

  19. Low-Activity Radioactive Wastes

    EPA Pesticide Factsheets

    In 2003 EPA published an Advance Notice of Proposed Rulemaking (ANPR) to collect public comment on alternatives for disposal of waste containing low concentrations of radioactive material ('low-activity' waste).

  20. [Sea dumping of radioactive wastes].

    PubMed

    König, L A

    1983-09-01

    This paper is an introduction to the problems of dumping at sea of radioactive wastes. A short survey is given on the dumping actions previously performed, the legal justification by international treaties, and the most important radioecological questions.

  1. Progresses in proton radioactivity studies

    SciTech Connect

    Ferreira, L. S.; Maglione, E.

    2016-07-07

    In the present talk, we will discuss recent progresses in the theoretical study of proton radioactivity and their impact on the present understanding of nuclear structure at the extremes of proton stability.

  2. Radioactivity of the Cooling Water

    DOE R&D Accomplishments Database

    Wigner, E. P.

    1943-03-01

    The most important source of radioactivity at the exit manifold of the pile will be due to O{sup 19}, formed by neutron absorption of O{sup 18}. A recent measurement of Fermi and Weil permits to estimate that it will be safe to stay about 80 minutes daily close to the exit manifolds without any shield. Estimates are given for the radioactivities from other sources both in the neighborhood and farther away from the pile.

  3. Predicted halflives for cluster radioactivities

    NASA Astrophysics Data System (ADS)

    Poenaru, D. N.; Greiner, W.; Ivascu, M.

    1989-10-01

    The main results of the analytical superasymmetric fission model, describing in a unified manner cluster radioactivities, alpha-decay and cold fission processes, are briefly reviewed. Predicted halflives for 14C, 24, 25, 26Ne, 28, 30Mg and 32Si radioactivities in the range 10 11-10 26 s and the corresponding branching ratios relative to α-decay 10 -16 - 10 -9 have been experimentally confirmed within 1.5 orders of magnitude.

  4. Radioactive Semivolatiles in Nuclear Fuel Reprocessing

    SciTech Connect

    Jubin, R. T.; Strachan, D. M.; Ilas, G.; Spencer, B. B.; Soelberg, N. R.

    2014-09-01

    In nuclear fuel reprocessing, various radioactive elements enter the gas phase from the unit operations found in the reprocessing facility. In previous reports, the pathways and required removal were discussed for four radionuclides known to be volatile, 14C, 3H, 129I, and 85Kr. Other, less volatile isotopes can also report to the off-gas streams in a reprocessing facility. These were reported to be isotopes of Cs, Cd, Ru, Sb, Tc, and Te. In this report, an effort is made to determine which, if any, of 24 semivolatile radionuclides could be released from a reprocessing plant and, if so, what would be the likely quantities released. As part of this study of semivolatile elements, the amount of each generated during fission is included as part of the assessment for the need to control their emission. Also included in this study is the assessment of the cooling time (time out of reactor) before the fuel is processed. This aspect is important for the short-lived isotopes shown in the list, especially for cooling times approaching 10 y. The approach taken in this study was to determine if semivolatile radionuclides need to be included in a list of gas-phase radionuclides that might need to be removed to meet Environmental Protection Agency (EPA) and Nuclear Regulatory Commission (NRC) regulations. A list of possible elements was developed through a literature search and through knowledge and literature on the chemical processes in typical aqueous processing of nuclear fuels. A long list of possible radionuclides present in irradiated fuel was generated and then trimmed by considering isotope half-life and calculating the dose from each to a maximum exposed individual with the US EPA airborne radiological dispersion and risk assessment code CAP88 (Rosnick 1992) to yield a short list of elements that actually need to be considered for control because they require high decontamination factors to meet a reasonable fraction of the regulated release. Each of these elements is

  5. Storage depot for radioactive material

    DOEpatents

    Szulinski, Milton J.

    1983-01-01

    Vertical drilling of cylindrical holes in the soil, and the lining of such holes, provides storage vaults called caissons. A guarded depot is provided with a plurality of such caissons covered by shielded closures preventing radiation from penetrating through any linear gap to the atmosphere. The heat generated by the radioactive material is dissipated through the vertical liner of the well into the adjacent soil and thus to the ground surface so that most of the heat from the radioactive material is dissipated into the atmosphere in a manner involving no significant amount of biologically harmful radiation. The passive cooling of the radioactive material without reliance upon pumps, personnel, or other factor which might fail, constitutes one of the most advantageous features of this system. Moreover this system is resistant to damage from tornadoes or earthquakes. Hermetically sealed containers of radioactive material may be positioned in the caissons. Loading vehicles can travel throughout the depot to permit great flexibility of loading and unloading radioactive materials. Radioactive material can be shifted to a more closely spaced caisson after ageing sufficiently to generate much less heat. The quantity of material stored in a caisson is restricted by the average capacity for heat dissipation of the soil adjacent such caisson.

  6. Radioactive materials in recycled metals

    SciTech Connect

    Lubenau, J.O.; Yusko, J.G.

    1995-04-01

    In recent years, the metal recycling industry has become increasingly aware of an unwanted component in metal scrap-radioactive material. Worldwide, there have been 35 instances where radioactive sources were unintentionally smelted in the course of recycling metal scrap. In some cases contaminated metal consumer products were distributed internationally. In at least one case, serious radiation exposures of workers and the public occurred. Radioactive material appearing in metal scrap includes sources subject to licensing under the Atomic Energy Act and also naturally occurring radioactive material. U.S. mills that have smelted a radioactive source face costs resulting from decontamination, waste disposal, and lost profits that range from 7 to 23 million U.S. dollars for each event. To solve the problem, industry and the government have jointly undertaken initiatives to increase awareness of the problem within the metal recycling industry. Radiation monitoring of recycled metal scrap is being performed increasingly by mills and, to a lesser extent, by scrap processors. The monitoring does not, however, provide 100% protection. Improvements in regulatory oversight by the government could stimulate improved accounting and control of licensed sources. However, additional government effort in this area must be reconciled with competing priorities in radiation safety and budgetary constraints. The threat of radioactive material in recycled metal scrap will continue for the foreseeable future and, thus, poses regulatory policy challenges for both developed and developing nations.

  7. Radioactive materials in recycled metals.

    PubMed

    Lubenau, J O; Yusko, J G

    1995-04-01

    In recent years, the metal recycling industry has become increasingly aware of an unwanted component in metal scrap--radioactive material. Worldwide, there have been 35 instances where radioactive sources were unintentionally smelted in the course of recycling metal scrap. In some cases contaminated metal consumer products were distributed internationally. In at least one case, serious radiation exposures of workers and the public occurred. Radioactive material appearing in metal scrap includes sources subject to licensing under the Atomic Energy Act and also naturally occurring radioactive material. U.S. mills that have smelted a radioactive source face costs resulting from decontamination, waste disposal, and lost profits that range from 7 to 23 million U.S. dollars for each event. To solve the problem, industry and the government have jointly undertaken initiatives to increase awareness of the problem within the metal recycling industry. Radiation monitoring of recycled metal scrap is being performed increasingly by mills and, to a lesser extent, by scrap processors. The monitoring does not, however, provide 100% protection. Improvements in regulatory oversight by the government could stimulate improved accounting and control of licensed sources. However, additional government effort in this area must be reconciled with competing priorities in radiation safety and budgetary constraints. The threat of radioactive material in recycled metal scrap will continue for the foreseeable future and, thus, poses regulatory policy challenges for both developed and developing nations.

  8. 49 CFR 172.556 - RADIOACTIVE placard.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false RADIOACTIVE placard. 172.556 Section 172.556... SECURITY PLANS Placarding § 172.556 RADIOACTIVE placard. (a) Except for size and color, the RADIOACTIVE... on the RADIOACTIVE placard must be white in the lower portion with a yellow triangle in the...

  9. Predicting induced radioactivity for the accelerator operations at the Taiwan Photon Source.

    PubMed

    Sheu, R J; Jiang, S H

    2010-12-01

    This study investigates the characteristics of induced radioactivity due to the operations of a 3-GeV electron accelerator at the Taiwan Photon Source (TPS). According to the beam loss analysis, the authors set two representative irradiation conditions for the activation analysis. The FLUKA Monte Carlo code has been used to predict the isotope inventories, residual activities, and remanent dose rates as a function of time. The calculation model itself is simple but conservative for the evaluation of induced radioactivity in a light source facility. This study highlights the importance of beam loss scenarios and demonstrates the great advantage of using FLUKA in comparing the predicted radioactivity with corresponding regulatory limits. The calculated results lead to the conclusion that, due to fairly low electron consumption, the radioactivity induced in the accelerator components and surrounding concrete walls of the TPS is rather moderate and manageable, while the possible activation of air and cooling water in the tunnel and their environmental releases are negligible.

  10. Endangered and Extinct Radioactivity

    NASA Astrophysics Data System (ADS)

    Leising, M. D.

    1993-07-01

    Gamma ray spectroscopy holds great promise for probing nucleosynthesis in individual nucleosynthesis events, via observations of short-lived radioactivity, and for measuring global galactic nucleosynthesis today with detections of longer-lived radioactivity. Many of the astrophysical issues addressed by these observations are precisely those that must be understood in order to interpret observations of extinct radioactivity in meteorites. It was somewhat surprising that the former case was realized first for a Type II supernova, when both 56Co [1] and 57Co [2] were detected in SN 1987A. These provide unprecedented constraints on models of Type II explosions. Live 26Al in the galaxy might come from Type II supernovae and their progenitors, and if this is eventually shown to be the case, can constrain massive star evolution, supernova nucleosynthesis, the galactic Type II supernova rate, and even models of the chemical evolution of the galaxy [3]. Titanium-44 is produced primarily in the alpha-rich freezeout from nuclear statistical equilibrium, possibly in Type Ia [4] and almost certainly in Type II supernovae [5]. The galactic recurrence time of these events is comparable to the 44Ti lifetime, so we expect to be able to see at most a few otherwise unseen 44Ti remnants at any given time. No such remnants have been detected yet [6]. Very simple arguments lead to the expectation that about 4 x 10^-4 M(sub)solar mass of 44Ca are produced per century. The product of the supernova frequency times the 44Ti yield per event must equal this number. Even assuming that only the latest event would be seen, rates in excess of 2 century^-1 are ruled out at >=99% confidence by the gamma ray limits. Only rates less than 0.3 century^-1 are acceptable at >5% confidence, and this means that the yield per event must be >10^-3 M(sub)solar mass to produce the requisite 44Ca. Rates this low are incompatible with current estimates for Type II supernovae and yields this high are also very

  11. Isotope fractionation

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    A rash of new controversy has emerged around the subject of mass-independent isotope fractionation effects, particularly in the case of the oxygen isotopes. To be sure, the controversy has been around for awhile, but it has been given new impetus by the results of a recent study by Mark H. Thiemens and John E. Heidenreich III of the University of California, San Diego (Science, March 4, 1983).Gustav Arrhenius has been trying to convince the planetary science community that chemical effects in isotope fractionation processes could explain observations in meteorites that appear to be outside of the traditionally understood mass-dependent fractionations (G. Arrhenius, J . L. McCrumb, and N. F. Friedman, Astrophys. Space Sci, 65, 297, 1974). Robert Clayton had made the basic observations of oxygen in carbonaceous chondrites that the slope of the δ17 versus δ18 line was 1 instead of the slope of ½ characteristic of terrestrial rocks and lunar samples (Ann. Rev. Nucl. Part. Sci., 28, 501, 1978). The mass-independent effects were ascribed to the apparent contribution of an ancient presolar system component of O16.

  12. Flowsheets and source terms for radioactive waste projections

    SciTech Connect

    Forsberg, C.W.

    1985-03-01

    Flowsheets and source terms used to generate radioactive waste projections in the Integrated Data Base (IDB) Program are given. Volumes of each waste type generated per unit product throughput have been determined for the following facilities: uranium mining, UF/sub 6/ conversion, uranium enrichment, fuel fabrication, boiling-water reactors (BWRs), pressurized-water reactors (PWRs), and fuel reprocessing. Source terms for DOE/defense wastes have been developed. Expected wastes from typical decommissioning operations for each facility type have been determined. All wastes are also characterized by isotopic composition at time of generation and by general chemical composition. 70 references, 21 figures, 53 tables.

  13. Exploring Radioactive Decay and Geochronology through Hydrostatic Principles

    NASA Astrophysics Data System (ADS)

    Claiborne, L. L.; Miller, C. F.

    2008-12-01

    One of the most essential tools to unraveling Earth's history and the processes involved in shaping our planet is an understanding of deep time and the timescales involved in geologic processes. The primary process that allows quantification of this history is radioactive decay of unstable isotopes within earth materials, and as one of the most essential tools in geology, this concept is taught at all levels of geoscience education. The concept of radioactive decay contains nuances that are often lost on students during lectures, and students often express low confidence in their comprehension of the concept. The goal of this laboratory activity is for students to understand radioactive decay including what controls it, how it proceeds and what information it provides, along with developing higher level scientific skills including making observations and predictions, and creating and interpreting quantitative graphical representations of data. The activity employs graduated beakers, shampoo, and stopwatches. Students pour shampoo put into an upper beaker (representing the parent isotope) with a hole in the base and allow it to flow into a lower beaker (representing the daughter isotope). Students measure changes in liquid depth with time, relating this to the amount of decay and its dependence on the amount of parent available (depth of liquid) and the decay constant (area of the hole in the beaker). Several beakers with varying sized holes illustrate variations specific to the different parent isotopes. They then explore graphical representations of their "decay" data, discovering for themselves which kinds of plots yield the equations and constants that control the decay process and the derived quantity of the "half-life", and are therefore the most useful. Making their own measurements, creating graphs, and then calculating these fundamental quantities is both enlightening and empowering. An advanced variation of this experiment involves students predicting the

  14. Radioactive-induced tumors by phosphorus-32 as colloidal compound

    SciTech Connect

    Ubios, A.M.; Silberman, F.S.; Cabrini, R.L.

    1983-05-01

    Chromic colloidal phosphate labeled with 32P, which has been proposed for the treatment of several articular diseases, was injected intra-articularly in the knee joint of adult Wistar rats. After a 270 days minimum latent period, tumors began to appear in the injected zone, to a 70% frequency. Ten lung metastases were detected. In five cases, squamous cell carcinomas were induced in the injected area. The relevance of a sound evaluation of the risk involved in treatments with radioactive isotopes, is discussed.

  15. Isotope and Nuclear Chemistry Division annual report, FY 1983

    SciTech Connect

    Heiken, J.H.; Lindberg, H.A.

    1984-05-01

    This report describes progress in the major research and development programs carried out in FY 1983 by the Isotope and Nuclear Chemistry Division. It covers radiochemical diagnostics of weapons tests; weapons radiochemical diagnostics research and development; other unclassified weapons research; stable and radioactive isotope production, separation, and applications (including biomedical applications); element and isotope transport and fixation; actinide and transition metal chemistry; structural chemistry, spectroscopy, and applications; nuclear structure and reactions; irradiation facilities; advanced analytical techniques; development and applications; atmospheric chemistry and transport; and earth and planetary processes.

  16. Artificial Intelligence and Robotics.

    DTIC Science & Technology

    1984-02-01

    D-Ai42 488 ARTIFICIAL INEELLIGENCE AND ROBOTICS (U) MASSACHUSETTS i/1 INST OF TECH CAMBRIDGE ARTIFICIAL INTELLIGENCE LAB M BRADY FEB 84 AI-M-756...Subtile) S. TYPE OF REPORT A PERIOD COVERED Artificial Intelligence and Robotics 6. PERFORMING ORG. REPORT NUMBER 7. AUTHOR(*) S. CONTRACT OR GRANT NUMBER...Identify by block niiniber) -. Since Robotics is the field concerned with the connection of perception to action, Artificial Intelligence must have a

  17. Artificial life and Piaget.

    PubMed

    Mueller, Ulrich; Grobman, K H.

    2003-04-01

    Artificial life provides important theoretical and methodological tools for the investigation of Piaget's developmental theory. This new method uses artificial neural networks to simulate living phenomena in a computer. A recent study by Parisi and Schlesinger suggests that artificial life might reinvigorate the Piagetian framework. We contrast artificial life with traditional cognitivist approaches, discuss the role of innateness in development, and examine the relation between physiological and psychological explanations of intelligent behaviour.

  18. Radioactivity measurements using storage phosphor technology

    SciTech Connect

    Cheng, Y.T.; Hwang, J.; Hutchinson, M.R.

    1995-10-01

    We propose to apply a recently developed charged particle radiation imaging concept in bio-medical research for fast, cost-effective characterization of radionuclides in contaminated sites and environmental samples. This concept utilizes sensors with storage photostimulable phosphor (SPP) technology as radiation detectors. They exhibit high sensitivity for all types of radiation and the response is linear over a wide dynamic range (>10{sup 5}), essential for quantitative analysis. These new sensors have an Active area of up to 35 cm x 43 cm in size and a spatial resolution as fine as 50 {mu}m. They offer considerable promise as large area detectors for fast characterization of radionuclides with an added ability to locate and identify hot spots. Tests with SPP sensors have found that a single alpha particle effect can be observed and an alpha field of 100 dpm/100 cm{sup 2} or a beta activity of 0.1 dpm/mm{sup 2} or gamma radiation of few {mu}R/hr can all be measured in minutes. Radioactive isotopes can further be identified by energy discrimination which is accomplished by placing different thicknesses of filter material in front of the sensor plate. For areas with possible neutron contamination, the sensors can be coupled to a neutron to charged particle converter screen, such as dysprosium foil to detect neutrons. Our study has shown that this approach can detect a neutron flux of 1 n/cm{sup 2}s or lower, again with only minutes of exposure time. The utilization of these new sensors can significantly reduce the time and cost required for many site characterization and environmental monitoring tasks. The {open_quotes}exposure{close_quotes} time for mapping radioactivity in an environmental sample may be in terms of minutes and offer a positional resolution not obtainable with presently used counting equipment. The resultant digital image will lend itself to ready analysis.

  19. PRODUCTION OF RADIOACTIVE IODINE.

    SciTech Connect

    SCHLYER,D.J.

    2001-08-08

    Probably the most widely used cyclotron produced radiohalogen is I-123. It has gradually replaced I-131 as the isotope of choice for diagnostic radiopharmaceuticals containing radioiodine. It gives a much lower radiation dose to the patient and the gamma ray energy of 159 keV is ideally suited for use in a gamma camera. The gamma ray will penetrate tissue very effectively without excessive radiation dose. For this reason, it has in many instances replaced the reactor produced iodine-131 (Lambrecht and Wolf 1973). A great number of radiopharmaceuticals have been labeled using I-123 and the number is increasing. One of the most promising uses of I-123 is in the imaging of monoclonal antibodies to localize and visualize tumors. However, preclinical and clinical experiences with radiolabeled antibodies have not realized the expectations regarding specificity and sensitivity of tumor localization with these agents. It appears that much of the administered activity is not associated with the tumor site and only a small fraction actually accumulates there. Work continues in this area and tumor-associated antigens can be targets for specific antibody reagents.

  20. Artificial Behavior: An Idea.

    ERIC Educational Resources Information Center

    Steinhauer, Gene D.; Peden, Blaine F.

    1985-01-01

    Contrasts artificial behavior with artificial intelligence, traces Law of Effect's development from a verbal statement into a mathematical model providing algorithms for artificial behavior programs, and describes an attempt to use computer graphics and animation to simulate behavior and teach abstract concepts. (MBR)

  1. Isotope tracers help manage water resources

    SciTech Connect

    Smith, D.; Hudson, B.; Davisson, L.

    1997-11-01

    Livermore isotope scientists are using stable and radioactive isotopes to learn about groundwater sources, ages, travel times, and flow paths and to determine the path and extent of contaminant movement in the water. These studies started at the Nevada Test Site because of concern about the transport in groundwater of contaminants from underground nuclear testing. When water managers can accurately predict where contaminated groundwater will be, they can avoid using it. Groundwater studies have also been performed for the Orange County Water District, Contra Costa County, and other public agencies, as well as at the Livermore site. Livermore scientists are some of the first to marry isotope tracing techniques and numerical groundwater models, using data from the former to verify and validate the predictions of the latter and thus provide a powerful forecasting tool for water managers.

  2. [Investigation of radioactivity measurement of medical radioactive waste].

    PubMed

    Koizumi, Kiyoshi; Masuda, Kazutaka; Kusakabe, Kiyoko; Kinoshita, Fujimi; Kobayashi, Kazumi; Yamamoto, Tetsuo; Kanaya, Shinichi; Kida, Tetsuo; Yanagisawa, Masamichi; Iwanaga, Tetsuo; Ikebuchi, Hideharu; Kusama, Keiji; Namiki, Nobuo; Okuma, Hiroshi; Fujimura, Yoko; Horikoshi, Akiko; Tanaka, Mamoru

    2004-11-01

    To explore the possibility of which medical radioactive wastes could be disposed as general wastes after keeping them a certain period of time and confirming that their radioactivity reach a background level (BGL), we made a survey of these wastes in several nuclear medicine facilities. The radioactive wastes were collected for one week, packed in a box according to its half-life, and measured its radioactivity by scintillation survey meter with time. Some wastes could reach a BGL within 10 times of half-life, but 19% of the short half-life group (group 1) including 99mTc and 123I, and 8% of the middle half-life group (group 2) including 67Ga, (111)In, and 201Tl did not reach a BGL within 20 times of half-life. A reason for delaying the time of reaching a BGL might be partially attributed to high initial radiation dose rate or heavy package weight. However, mixing with the nuclides of longer half-life was estimated to be the biggest factor affecting this result. When disposing medical radioactive wastes as general wastes, it is necessary to avoid mixing with radionuclide of longer half-life and confirm that it reaches a BGL by actual measurement.

  3. Informational Aspects of Isotopic Diversity in Biology and Medicine

    NASA Astrophysics Data System (ADS)

    Berezin, Alexander A.

    2004-10-01

    Use of stable and radioactive isotopes in biology and medicine is intensive, yet informational aspects of isotopes as such are largely neglected (A.A.Berezin, J.Theor.Biol.,1992). Classical distinguishability (``labelability'') of isotopes allows for pattern generation dynamics. Quantum mechanically advantages of isotopicity (diversity of stable isotopes) arise from (almost perfect) degeneracy of various isotopic configurations; this in turn allows for isotopic sweeps (hoppings) by resonance neutron tunneling (Eccles mechanism). Isotopic variations of de Broglie wavelength affect quantum tunneling, diffusivity, magnetic interactions (e.g. by Lorentz force), etc. Ergodicity principle (all isoenergetic states are eventually accessed) implies possibility of fast scanning of library of morphogenetic patterns (cf metaphors of universal ``Platonic'' Library of Patterns: e.g. J.L.Borges, R.Sheldrake) with subsequent Darwinian reinforcement (e.g. by targeted mutations) of evolutionary advantageous patterns and structures. Isotopic shifts in organisms, from viruses and protozoa to mammalians, (e.g. DNA with enriched or depleted C-13) are tools to elucidate possible informational (e.g. Shannon entropy) role of isotopicity in genetic (e.g. evolutionary and morphological), dynamical (e.g. physiological and neurological) as well as medical (e.g. carcinogenesis, aging) aspects of biology and medicine.

  4. IBM-2 calculation with configuration mixing for Ge isotopes

    NASA Astrophysics Data System (ADS)

    Padilla-Rodal, Elizabeth; Galindo-Uribarri, Alfredo

    2005-04-01

    Recent results on Coulomb excitation experiments of radioactive neutron-rich Ge isotopes at the Holifield Radioactive Ion Beam Facility allow the study of the systematic trend of B(E2; 0^+ ->2^+) between the sub-shell closures at N=40 and the N=50 [1]. The new information on the E2 transition strengths constitutes a stringent test for the nuclear models and has motivated us to revisit the use of Interacting Boson Model in this region. We show that the IBM-2 with configuration mixing is a successful model to describe the shape transition phenomena that take place around N=40 in stable germanium isotopes, as well as the predictions given by this model about the evolution of the structure for the radioactive ^78, 80, 82Ge nuclei. [1] E. Padilla-Rodal Ph.D. Thesis UNAM; submitted for publication.

  5. Large Isotope Spectrometer for Astromag

    NASA Technical Reports Server (NTRS)

    Binns, W. R.; Klarmann, J.; Israel, M. H.; Garrard, T. L.; Mewaldt, R. A.; Stone, E. C.; Ormes, J. F.; Streitmatter, R. E.; Rasmussen, I. L.; Wiedenbeck, M. E.

    1990-01-01

    The Large Isotope Spectrometer for Astromag (LISA) is an experiment designed to measure the isotopic composition and energy spectra of cosmic rays for elements extending from beryllium through zinc. The overall objectives of this investigation are to study the origin and evolution of galactic matter; the acceleration, transport, and time scales of cosmic rays in the galaxy; and search for heavy antinuclei in the cosmic radiation. To achieve these objectives, the LISA experiment will make the first identifications of individual heavy cosmic ray isotopes in the energy range from about 2.5 to 4 GeV/n where relativistic time dilation effects enhance the abundances of radioactive clocks and where the effects of solar modulation and cross-section variations are minimized. It will extend high resolution measurements of individual element abundances and their energy spectra to energies of nearly 1 TeV/n, and has the potential for discovering heavy anti-nuclei which could not have been formed except in extragalactic sources.

  6. Modelling seasonal variations of natural radioactivity in soils: A case study in southern Italy

    NASA Astrophysics Data System (ADS)

    Guagliardi, Ilaria; Rovella, Natalia; Apollaro, Carmine; Bloise, Andrea; Rosa, Rosanna De; Scarciglia, Fabio; Buttafuoco, Gabriele

    2016-12-01

    The activity of natural radionuclides in soil has become an environmental concern for local public and national authorities because of the harmful effects of radiation exposure on human health. In this context, modelling and mapping the activity of natural radionuclides in soil is an important research topic. The study was aimed to model, in a spatial sense, the soil radioactivity in an urban and peri-urban soils area in southern Italy to analyse the seasonal influence on soil radioactivity. Measures of gamma radiation naturally emitted through the decay of radioactive isotopes (potassium, uranium and thorium) were analysed using a geostatistical approach to map the spatial distribution of soil radioactivity. The activity of three radionuclides was measured at 181 locations using a high-resolution ?-ray spectrometry. To take into account the influence of season, the measurements were carried out in summer and in winter. Activity data were analysed by using a geostatistical approach and zones of relatively high or low radioactivity were delineated. Among the main processes which influence natural radioactivity such as geology, geochemical, pedological, and ecological processes, results of this study showed a prominent control of radio-emission measurements by seasonal changes. Low natural radioactivity levels were measured in December associated with winter weather and moist soil conditions (due to high rainfall and low temperature), and higher activity values in July, when the soil was dry and no precipitations occurred.

  7. Laser Isotope Enrichment for Medical and Industrial Applications

    SciTech Connect

    Leonard Bond

    2006-07-01

    Laser Isotope Enrichment for Medical and Industrial Applications by Jeff Eerkens (University of Missouri), Jay Kunze (Idaho State University), and Leonard Bond (Idaho National Laboratory) The principal isotope enrichment business in the world is the enrichment of uranium for commercial power reactor fuels. However, there are a number of other needs for separated isotopes. Some examples are: 1) Pure isotopic targets for irradiation to produce medical radioisotopes. 2) Pure isotopes for semiconductors. 3) Low neutron capture isotopes for various uses in nuclear reactors. 4) Isotopes for industrial tracer/identification applications. Examples of interest to medicine are targets to produce radio-isotopes such as S-33, Mo-98, Mo-100, W-186, Sn-112; while for MRI diagnostics, the non-radioactive Xe-129 isotope is wanted. For super-semiconductor applications some desired industrial isotopes are Si-28, Ga-69, Ge-74, Se-80, Te-128, etc. An example of a low cross section isotope for use in reactors is Zn-68 as a corrosion inhibitor material in nuclear reactor primary systems. Neutron activation of Ar isotopes is of interest in industrial tracer and diagnostic applications (e.g. oil-logging). . In the past few years there has been a sufficient supply of isotopes in common demand, because of huge Russian stockpiles produced with old electromagnetic and centrifuge separators previously used for uranium enrichment. Production of specialized isotopes in the USA has been largely accomplished using old ”calutrons” (electromagnetic separators) at Oak Ridge National Laboratory. These methods of separating isotopes are rather energy inefficient. Use of lasers for isotope separation has been considered for many decades. None of the proposed methods have attained sufficient proof of principal status to be economically attractive to pursue commercially. Some of the authors have succeeded in separating sulfur isotopes using a rather new and different method, known as condensation

  8. Is it necessary to raise awareness about technologically enhanced naturally occurring radioactive materials?

    PubMed

    Michalik, Bogusław

    2009-10-01

    Since radiation risks are usually considered to be related to nuclear energy, the majority of research on radiation protection has focused on artificial radionuclides in radioactive wastes, spent nuclear fuel or global fallout caused by A-bomb tests and nuclear power plant failures. Far less attention has been paid to the radiation risk caused by exposure to ionizing radiation originating from natural radioactivity enhanced due to human activity, despite the fact that technologically enhanced naturally occurring radioactive materials are common in many branches of the non-nuclear industry. They differ significantly from "classical" nuclear materials and usually look like other industrial waste. The derived radiation risk is usually associated with risk caused by other pollutants and can not be controlled by applying rules designed for pure radioactive waste. Existing data have pointed out a strong need to take into account the non-nuclear industry where materials containing enhanced natural radioactivity occur as a special case of radiation risk and enclose them in the frame of the formal control. But up to now there are no reasonable and clear regulations in this matter. As a result, the non-nuclear industries of concern are not aware of problems connected with natural radioactivity or they would expect negative consequences in the case of implementing radiation protection measures. The modification of widely comprehended environmental legislation with requirements taken from radiation protection seems to be the first step to solve this problem and raise awareness about enhanced natural radioactivity for all stakeholders of concern.

  9. Biomedical aspects of natural and manufactured environmental radioactivity

    SciTech Connect

    Hodge, V.

    1996-12-31

    While weapons testing has altered natural radioactivity background, manufactured radioactivity in most parts of the world constitutes but a very small fraction of the total alpha, beta, and gamma radioactivity in soil, air, water, and the biota. For example, in the early 1970s, we found what appeared to be the highest natural concentration of radioactivity ever reported in fish while attempting to measure the manufactured plutonium ({sup 239}Pu and {sup 240}Pu) in organs of oceanic tuna. The natural alpha emitter polonium ({sup 210}Po) was discovered in the same organs at orders of magnitude higher concentrations. In particular, the caecum, which is a digestive organ composed of many small closed-ended sacs, contained concentrations of polonium as high as 79 pCi/g of wet tissue and lesser amounts of two manufactured isotopes: 0.0001 pCi/g of plutonium and 0.01 pCi/g of radiocesium ({sup 137}Cs). This equates to {approximately}80 rem/yr of radiation dose to this organ, overwhelmingly from the natural polonium, or {approximately}5000 times higher than is found in the human liver, the highest polonium concentration in man. The average background radiation for humans, for comparison, is {approximately}0.2 rem/yr, but the dose for Japanese, whose diet is high in seafood, is {approximately}15 rem/yr. The question arose: {open_quotes}Are these high concentrations of natural polonium limited to oceanic fish?{close_quotes} To answer this question, polonium was determined in the organs of striped bass and catfish from Lake Mead. In a related study, the plutonium and radiocesium ({sup 137}Cs) distributions in soils were determined to ascertain the impact of weapons testing on the natural background radioactivity of soils.

  10. Building a LLNL Capability in Radioactive Ion Beam Experiments

    SciTech Connect

    Bernstein, L A; Becker, J A; Garrett, P E; Younes, W; Schiller, A

    2002-01-31

    The purpose of this LDRD was to establish a program at LLNL in radioactive ion beam (RIB) experiments that would use these experiments to address a wide range physics issues in both stellar nucleosynthesis and stockpile stewardship radiochemistry. The LDRD was funded for a total of two years (fiscal years 2000 and 2001) and transferred to the Physical Data Research Program in fiscal year 2002. Reactions on unstable nuclei and isomeric states play a central role in the formation of elements in both stars and nuclear devices. However, the abilities of reaction models to predict cross sections on radioactive nuclei are uncertain at best. This can be attributed to the lack of experimental data to guide reaction-modeling efforts. Only the 10% of all bound nuclei that can be formed with stable targets and beams have been accessed and studied. The proposed Rare Isotope Accelerator (RIA) and existing RIB facilities offer an unprecedented opportunity to address many of the outstanding questions in nuclear structure, reactions and astrophysics by enabling the observation of nuclear reactions with radioactive targets and/or beams. The primary goal of this LDRD is to develop three experimental capabilities for use with RIB experiments: (1) Level density and {gamma}-ray strength function measurements using statistical {gamma}-rays. (2) Charged particle-induced cross sections measurements on radioactive nuclei. (3) Neutron-induced cross section measurements on a radioactive target. RIA and RIB based experiments are the new frontier for nuclear physics. The joint DOE/NSF nuclear science advisory committee has named development of a RIA facility in the United States as the highest new construction priority. In addition to addressing the questions presented above, this LDRD has helped to establish a position for LLNL at the forefront of the international nuclear science community.

  11. Medical Isotope Production Analyses In KIPT Neutron Source Facility

    SciTech Connect

    Talamo, Alberto; Gohar, Yousry

    2016-01-01

    Medical isotope production analyses in Kharkov Institute of Physics and Technology (KIPT) neutron source facility were performed to include the details of the irradiation cassette and the self-shielding effect. An updated detailed model of the facility was used for the analyses. The facility consists of an accelerator-driven system (ADS), which has a subcritical assembly using low-enriched uranium fuel elements with a beryllium-graphite reflector. The beryllium assemblies of the reflector have the same outer geometry as the fuel elements, which permits loading the subcritical assembly with different number of fuel elements without impacting the reflector performance. The subcritical assembly is driven by an external neutron source generated from the interaction of 100-kW electron beam with a tungsten target. The facility construction was completed at the end of 2015, and it is planned to start the operation during the year of 2016. It is the first ADS in the world, which has a coolant system for removing the generated fission power. Argonne National Laboratory has developed the design concept and performed extensive design analyses for the facility including its utilization for the production of different radioactive medical isotopes. 99Mo is the parent isotope of 99mTc, which is the most commonly used medical radioactive isotope. Detailed analyses were performed to define the optimal sample irradiation location and the generated activity, for several radioactive medical isotopes, as a function of the irradiation time.

  12. Measuring and Modeling Naturally Occurring Radioactive Material: Interpreting the Relationship Between the Natural Radionuclides Present

    SciTech Connect

    Lombardo, A.J.; Mucha, A.F.

    2008-07-01

    The regulatory release of sites and facilities (property) for restricted or unrestricted use has evolved beyond prescribed levels to model-derived dose and risk based limits. Dose models for deriving corresponding soil and structure radionuclide concentration guidelines are necessarily simplified representations of complex processes. A conceptual site model is often developed to present a reasonable and somewhat conservative representation of the physical and chemical properties of the impacted material. Dose modeling software is then used to estimate resulting dose and/or radionuclide specific acceptance criteria (activity concentrations). When the source term includes any or all of the uranium, thorium or actinium natural decay series radionuclides the interpretation of the relationship between the individual radionuclides of the series is critical to a technically correct and complete assessment of risk and/or derivation of radionuclide specific acceptance criteria. Unlike man-made radionuclides, modeling and measuring naturally occurring radioactive material (NORM) and technologically enhanced NORM (TENORM) source terms involves the interpretation of the relationship between the radionuclide present, e.g., secular equilibrium, enrichment, depletion or transient equilibrium. Isotopes of uranium, radium, and thorium occur in all three natural decay series. Each of the three series also produces a radon gas isotope as one of its progeny. In nature, the radionuclides in the three natural decay series are in a state that is approaching or has achieved secular equilibrium, in which the activities of all radionuclides within each series are nearly equal. However, ores containing the three natural decay series may begin in approximate secular equilibrium, but after processing, equilibrium may be broken and certain elements (and the radioactive isotopes of that element) may be concentrated or removed. Where the original ore may have contained one long chain of natural

  13. Advances in artificial lungs.

    PubMed

    Ota, Kei

    2010-04-01

    Artificial lungs have already been developed as complete artificial organs, and results of many investigations based on innovative concepts have been reported continuously. In open-heart surgery, artificial lungs are used for extracorporeal circulation to maintain gas exchange, and the commercial products currently available perform adequately, including providing for antithrombogenicity. However, patients after cardiopulmonary arrest or severe respiratory/circulatory failure have required long-term assist with extracorporeal membrane oxygenation (ECMO). The number of artificial lungs used for ECMO in those cases has shown significant growth in recent years. Therefore, it is expected that durability and antithrombogenicity will ensure the prolonged use of an artificial lung for several weeks or months. Furthermore, interests in research are shifting to use of oxygenators as a bridge to lung transplantation and an implantable artificial lung. This paper discusses recent advances in artificial lungs, focusing on the current state and on trends in research and development.

  14. Radioactive Nanomaterials for Multimodality Imaging

    PubMed Central

    Chen, Daiqin; Dougherty, Casey A.; Yang, Dongzhi; Wu, Hongwei; Hong, Hao

    2016-01-01

    Nuclear imaging techniques, including primarily positron emission tomography (PET) and single-photon emission computed tomography (SPECT), can provide quantitative information for a biological event in vivo with ultra-high sensitivity, however, the comparatively low spatial resolution is their major limitation in clinical application. By convergence of nuclear imaging with other imaging modalities like computed tomography (CT), magnetic resonance imaging (MRI) and optical imaging, the hybrid imaging platforms can overcome the limitations from each individual imaging technique. Possessing versatile chemical linking ability and good cargo-loading capacity, radioactive nanomaterials can serve as ideal imaging contrast agents. In this review, we provide a brief overview about current state-of-the-art applications of radioactive nanomaterials in the circumstances of multimodality imaging. We present strategies for incorporation of radioisotope(s) into nanomaterials along with applications of radioactive nanomaterials in multimodal imaging. Advantages and limitations of radioactive nanomaterials for multimodal imaging applications are discussed. Finally, a future perspective of possible radioactive nanomaterial utilization is presented for improving diagnosis and patient management in a variety of diseases. PMID:27227167

  15. Toward a comprehensive description of decay properties for uranium isotopes

    NASA Astrophysics Data System (ADS)

    Qian, Yibin; Ren, Zhongzhou

    2016-12-01

    Within the enhanced density dependent cluster model, with specific concern for density distributions in related nuclei, we investigate α decay and cluster radioactivity in uranium isotopes in the range 217 ≤A ≤243 . The available experimental data are found to be well reproduced, especially including the very recently measured values of new neutron-deficient isotopes. The half-lives of possible cluster emissions are consequently predicted as well, and will be somewhat valuable for future detection. Moreover, β decay half-lives of these nuclei are also evaluated with respect to all kinds of β processes, while their spontaneous fission lifetimes are provided via an effective relationship between the half-life and crucial quantities, namely the fissility parameter and fission barriers. In this sense, a full understanding of decay properties in uranium isotopes is expected to be achieved by combining their various radioactive features.

  16. Global simulation of the carbon isotope exchange of terrestrial ecosystems

    NASA Astrophysics Data System (ADS)

    Ito, A.; Terao, Y.; Mukai, H.

    2009-12-01

    There remain large uncertainties in our quantification of global carbon cycle, which has close interactions with the climate system and is subject to human-induced global environmental change. Information on carbon isotopes is expected to reduce the uncertainty by providing additional constraints on net atmosphere-ecosystem exchange. This study attempted to simulate the dynamics of carbon isotopes at the global scale, using a process-based terrestrial ecosystem model: Vegetation Integrative SImulator for Trace gases (VISIT). The base-model of carbon cycle (Sim-CYCLE, Ito 2003) has already considered stable carbon isotope composition (13C/12C), and here radioactive carbon isotope (14C) was included. The isotope ratios characterize various aspects of terrestrial carbon cycle, which is difficult to be constrained by sole mass balance. For example, isotopic discrimination by photosynthetic assimilation is closely related with leaf stomatal conductance and composition of C3 and C4 plant in grasslands. Isotopic disequilibrium represents mean residence time of terrestrial carbon pools. In this study, global simulations (spatial resolution 0.5-deg, time-step 1-month) were conducted during the period 1901 to 2100 on the basis of observed and projected atmospheric CO2, climate, and land-use conditions. As anthropogenic CO2 accumulates in the atmosphere, heavier stable carbon isotope (13C) was diluted, while radioactive carbon isotope (14C) is strongly affected by atomic bomb experiments mainly in the 1950s and 1960s. The model simulated the decadal change in carbon isotope compositions. Leaf carbon with shorter mean residence time responded rapidly to the atmospheric change, while plant stems and soil humus showed substantial time-lag, leading to large isotopic disequilibrium. In the future, the isotopic disequilibrium was estimated to augment, due to accelerated rate of anthropogenic CO2 accumulation. Spatial distribution of stable isotope composition (12C/13C, or d13C) was

  17. Enhanced Radioactive Material Source Security.

    PubMed

    Klinger, Joseph G

    2016-02-01

    Requirements for additional security measures for sealed radioactive sources have evolved since they were first implemented after the terrorist events of 11 September 2001. This paper will describe the sequence of those measures, commencing with the early orders issued by the U.S. Nuclear Regulatory Commission to the May 2013 adoption of 10 CFR Part 37, Physical Protections of Category 1 and Category 2 Quantities of Radioactive Material. Part 37 requirements will be discussed in detail, as the 37 NRC Agreement States, which regulate approximately 88% of the radioactive material licensees, will be required to enact by 19 March 2016. In addition to the Part 37 requirements, the paper will also highlight some of the other ongoing efforts of the U.S. Department of Energy's National Nuclear Security Administration's Global Threat Reduction Initiative and the Conference of Radiation Control Program Directors.

  18. Distribution of artificial radionuclides in lacustrine sediments in China.

    PubMed

    Wu, Fengchang; Zheng, Jian; Liao, Haiqing; Yamada, Masatoshi

    2011-07-01

    Establishing accurate historical records of the distribution, inventory and source of artificial radionuclides in the environment is important for environmental monitoring and radiological health protection due to their potential toxicity, and is also useful for identification and risk assessment of possible future environmental inputs of radionuclides from nuclear weapons tests and accidental release from the nuclear fuel reprocessing facilities or nuclear power reactors. A sector-field inductively coupled plasma mass spectrometer was used to study the recent sedimentation of Pu isotopes in 11 lakes in China. The distribution of (137)Cs was investigated using the conventional radiometric analytical methods. Based on the isotopic compositions of Pu and the activity ratio of (137)Cs/(239+240)Pu, the sources of artificial radionuclides were identified. The potential applications of Pu isotopes for sediment dating and for regional and global environmental change studies were discussed.

  19. Computer Simulation of Radioactive Decay

    NASA Astrophysics Data System (ADS)

    Jesse, Kenneth E.

    2003-12-01

    The straightforward way to determine the half-life of a radioactive substance is to measure its activity in each of a series of time intervals, plot the data as a function of the accumulated time on semilog paper, and then measure the slope of the graph. A computer simulation of this procedure follows based on material presented in Clifford E. Swartz's excellent book, Used Math. He presents a very fine mathematical derivation of the exponential law of decay for radioactive atoms in Chapter 4. A brief summary follows using his notation and equation numbers.

  20. Radioactive dating of the elements

    NASA Technical Reports Server (NTRS)

    Cowan, John J.; Thielemann, Friedrich-Karl; Truran, James W.

    1991-01-01

    The extent to which an accurate determination of the age of the Galaxy, and thus a lower bound on the age of the universe, can be obtained from radioactive dating is discussed. Emphasis is given to the use of the long-lived radioactive nuclei Re-187, Th-232, U-238, and U-235. The nature of the production sites of these and other potential Galactic chronometers is examined along with their production ratios. Age determinations from models of nucleocosmochronology are reviewed and compared with age determination from stellar sources and age constraints form cosmological considerations.

  1. Induced radioactivity in LDEF components

    NASA Technical Reports Server (NTRS)

    Harmon, B. A.; Fishman, G. J.; Parnell, T. A.; Laird, C. E.

    1992-01-01

    A systematic study of the induced radioactivity of the Long Duration Exposure Facility (LDEF) is being carried out in order to gather information about the low earth orbit radiation environment and its effects on materials. The large mass of the LDEF spacecraft, its stabilized configuration, and long mission duration have presented an opportunity to determine space radiation-induced radioactivities with a precision not possible before. Data presented include preliminary activities for steel and aluminum structural samples, and activation subexperiment foils. Effects seen in the data show a clear indication of the trapped proton anisotropy in the South Atlantic Anomaly and suggest contributions from different sources of external radiation fluxes.

  2. Storage containers for radioactive material

    DOEpatents

    Groh, E.F.; Cassidy, D.A.; Dates, L.R.

    1980-07-31

    A radioactive material storage system is claimed for use in the laboratory having a flat base plate with a groove in one surface thereof and a hollow pedestal extending perpendicularly away from the other surface thereof, a sealing gasket in the groove, a cover having a filter therein and an outwardly extending flange which fits over the plate, the groove and the gasket, and a clamp for maintaining the cover and the plate sealed together. The plate and the cover and the clamp cooperate to provide a storage area for radioactive material readily accessible for use or inventory. Wall mounts are provided to prevent accidental formation of critical masses during storage.

  3. Storage containers for radioactive material

    DOEpatents

    Groh, Edward F.; Cassidy, Dale A.; Dates, Leon R.

    1981-01-01

    A radioactive material storage system for use in the laboratory having a flat base plate with a groove in one surface thereof and a hollow pedestal extending perpendicularly away from the other surface thereof, a sealing gasket in the groove, a cover having a filter therein and an outwardly extending flange which fits over the plate, the groove and the gasket, and a clamp for maintaining the cover and the plate sealed together, whereby the plate and the cover and the clamp cooperate to provide a storage area for radioactive material readily accessible for use or

  4. Managing potentially radioactive scrap metal

    SciTech Connect

    2002-11-19

    The National Council on Radiation Protection and Measurements published NCRP Report No. 141 on November 19, 2002. Contract DE-FG02-98CH10945 provided the sole support for this report titled ''Managing Potentially Radioactive Scrap Metal.'' Some preliminary work supported by the U.S. Environmental Protection Agency that led to an NCRP Letter Report provided some background information for this work. NCRP Report No. 141 provides recommendations on the methodologies and techniques available to the United States for disposing of radioactive, contaminated scrap metals.

  5. Radioactive Ion Beams and Radiopharmaceuticals

    NASA Astrophysics Data System (ADS)

    Laxdal, R. E.; Morton, A. C.; Schaffer, P.

    2014-02-01

    Experiments performed at radioactive ion beam facilities shed new light on nuclear physics and nuclear structure, as well as nuclear astrophysics, materials science and medical science. The many existing facilities, as well as the new generation of facilities being built and those proposed for the future, are a testament to the high interest in this rapidly expanding field. The opportunities inherent in radioactive beam facilities have enabled the search for radioisotopes suitable for medical diagnosis or therapy. In this article, an overview of the production techniques and the current status of RIB facilities and proposals will be presented. In addition, accelerator-generated radiopharmaceuticals will be reviewed.

  6. [Radioactive labeling of Blatella germanica].

    PubMed

    Metzger, R; Hanisch, J; Regenstein, W

    1979-06-01

    For ecological investigations in natural populations of Blatella germanica a new method of dry incorporation of a porcelain tracer is developed. The quality of this method in contrast with other non radioactive and at present radioactive methods depends on the stable position of the tracer and the possibility of taking different marking substances for individually marking a large number of experimental animals. The identification bases on the previously investigated half-life values. The new method in combination with the recaptivate method is a good possibility to analyse a population of cockroaches.

  7. Radioactive dating of the elements

    NASA Technical Reports Server (NTRS)

    Cowan, John J.; Thielemann, Friedrich-Karl; Truran, James W.

    1991-01-01

    The extent to which an accurate determination of the age of the Galaxy, and thus a lower bound on the age of the universe, can be obtained from radioactive dating is discussed. Emphasis is given to the use of the long-lived radioactive nuclei Re-187, Th-232, U-238, and U-235. The nature of the production sites of these and other potential Galactic chronometers is examined along with their production ratios. Age determinations from models of nucleocosmochronology are reviewed and compared with age determination from stellar sources and age constraints form cosmological considerations.

  8. [Decorporation agents for internal radioactive contamination].

    PubMed

    Ohmachi, Yasushi

    2015-01-01

    When radionuclides are accidentally ingested or inhaled, blood circulation or tissue/organ deposition of the radionuclides causes systemic or local radiation effects. In such cases, decorporation therapy is used to reduce the health risks due to their intake. Decorporation therapy includes reduction and/or inhibition of absorption from the gastrointestinal tract, isotopic dilution, and the use of diuretics, adsorbents, and chelating agents. For example, penicillamine is recommended as a chelating agent for copper contamination, and diethylene triamine pentaacetic acid is approved for the treatment of internal contamination with plutonium. During chelation therapy, the removal effect of the drugs should be monitored using a whole-body counter and/or bioassay. Some authorities, such as the National Council on Radiation Protection and Measurements and International Atomic Energy Agency, have reported recommended decorporation agents for each radionuclide. However, few drugs are approved by the US Food and Drug Administration, and many are off-label-use agents. Because many decontamination agents are drugs that have been available for a long time and have limited efficacy, the development of new, higher-efficacy drugs has been carried out mainly in the USA and France. In this article, in addition to an outline of decorporation agents for internal radioactive contamination, an outline of our research on decorporation agents for actinide (uranium and plutonium) contamination and for radio-cesium contamination is also presented.

  9. The production of accelerated radioactive ion beams

    SciTech Connect

    Olsen, D.K.

    1993-11-01

    During the last few years, substantial work has been done and interest developed in the scientific opportunities available with accelerated radioactive ion beams (RIBs) for nuclear physics, astrophysics, and applied research. This interest has led to the construction, development, and proposed development of both first- and second-generation RIB facilities in Asia, North America, and Europe; international conferences on RIBs at Berkeley and Louvain-la-Neuve; and many workshops on specific aspects of RIB production and science. This paper provides a discussion of both the projectile fragmentation, PF, and isotope separator on-line, ISOL, approach to RIB production with particular emphasis on the latter approach, which employs a postaccelerator and is most suitable for nuclear structure physics. The existing, under construction, and proposed facilities worldwide are discussed. The paper draws heavily from the CERN ISOLDE work, the North American IsoSpin Laboratory (ISL) study, and the operating first-generation RIB facility at Louvain-la-Neuve, and the first-generation RIB project currently being constructed at ORNL.

  10. On feasibility of a closed nuclear power fuel cycle with minimum radioactivity

    SciTech Connect

    Andrianova, E. A.; Davidenko, V. D.; Tsibulskiy, V. F.

    2015-12-15

    Practical implementation of a closed nuclear fuel cycle implies solution of two main tasks. The first task is creation of environmentally acceptable operating conditions of the nuclear fuel cycle considering, first of all, high radioactivity of the involved materials. The second task is creation of effective and economically appropriate conditions of involving fertile isotopes in the fuel cycle. Creation of technologies for management of the high-level radioactivity of spent fuel reliable in terms of radiological protection seems to be the hardest problem.

  11. Feasibility of Space Disposal of Radioactive Nuclear Waste. 1: Executive Summary

    NASA Technical Reports Server (NTRS)

    1973-01-01

    This NASA study, performed at the request of the AEC, concludes that transporting radioactive waste (primarily long-lived isotopes) into space is feasible. Tentative solutions are presented for technical problems involving safe packaging. Launch systems (existing and planned), trajectories, potential hazards, and various destinations were evaluated. Solar system escape is possible and would have the advantage of ultimate removal of the radioactive waste from man's environment. Transportation costs would be low (comparable to less than a 5 percent increase in the cost of electricity) even though more than 100 space shuttle launches per year would be required by the year 2000.

  12. Evaluation of induced radioactivity in structural material of Toshiba Training Reactor 'TTR1'.

    PubMed

    Uematsu, Mikio; Kurosawa, Masahiko; Haruguchi, Yoshiko

    2005-01-01

    A decommissioning programme for the Toshiba Training Reactor (TTR1), a swimming pool type reactor used for reactor physics experiments and material irradiation, was started in August 2001. As a part of the programme, induced radioactivity in structural material was evaluated using neutron flux data obtained with the three-dimensional Sn code TORT. Induced activity was calculated with the isotope generation code ORIGEN-79 using activation cross section data created from multi-group library based on JENDL-3. The obtained results for radioactivities such as 60Co, 65Zn, 54Mn and 152Eu were compared with measured ones, and the present calculational method was confirmed to have enough accuracy.

  13. [The history of radioactivity and its applications in hygiene and therapy].

    PubMed

    Corrao, Carmela Romana Natalina; Serarcangeli, Carla

    2011-01-01

    Since Antiquity, the observation of matter and its composition has been fascinating for the human mind. It represented the core of philosophical studies since the atomistic theory by Leucippus and Democritus, as well as of the opposed theory of elements by Empedocles, Plato and Aristoteles. Research on the atom, on its spontaneous or artificial disgregation, on the practical application of radioactive substances has strongly influenced daily life and the development of knowledge. Products containing radioactive substances have been used, often without regulation or control, in many scientific fields, as well as in medicine and cosmetics.

  14. The SPES Radioactive-Ion Beam Facility of INFN

    NASA Astrophysics Data System (ADS)

    de Angelis, G.; Prete, G.; Andrighetto, A.; Manzolaro, M.; Corradetti, S.; Scarpa, D.; Rossignoli, M.; Monetti, A.; Lollo, M.; Calderolla, M.; Vasquez, J.; Zafiropoulos, D.; Sarchiapone, L.; Benini, D.; Favaron, P.; Rigato, M.; Pegoraro, R.; Maniero, D.; Comunian, M.; Maggiore, M.; Lombardi, A.; Piazza, L.; Porcellato, A. M.; Roncolato, C.; Bisoffi, G.; Pisent, A.; Galatà, A.; Giacchini, M.; Bassato, G.; Canella, S.; Gramegna, F.; Valiente, J.; Bermudez, J.; Mastinu, P. F.; Esposito, J.; Wyss, J.; Russo, A.; Zanella, S.; Calabretta, L.

    2015-11-01

    A new radioactive-ion beam (RIB) facility (SPES) is presently under construction at the Legnaro National Laboratories of INFN. The SPES facility is based on the ISOL method using a UCx direct target able to sustain a power of 10 kW. The primary proton beam will be provided by a high-current cyclotron accelerator with energy of 35-70 MeV and a beam current of 0.2-0.5 mA. Neutron-rich radioactive ions will be produced by proton-induced fission on a uranium target at an expected fission rate of the order of 1013 fissions per second. After ionization and selection the exotic isotopes will be re-accelerated by the ALPI superconducting LINAC at energies of 10A MeV for masses in the region A=130 amu. The expected secondary beam rates are of the order of 107-109 pps. The aim of the SPES facility is to deliver high-intensity radioactive-ion beams of neutron-rich nuclei for nuclear physics research, as well as to be an interdisciplinary research center for radioisotope production for medicine and for neutron beams.

  15. Evaluate cement with radioactive tracers, directional gamma ray logs

    SciTech Connect

    1996-07-01

    Use of radioactive tracers to evaluate hydraulic fractures has recently been extended through the use of directional gamma ray measurements. The directional gamma ray logging tool determines the azimuthal direction of gamma rays from radioactive isotope-tagged fracture proppants to estimate the fracture direction in well-controlled circumstances. The technology also provides new ways of evaluating primary and squeeze cement jobs by enhancing information from directional gamma ray data with advanced image processing techniques. By tagging the cement with a uniform quantity per unit volume of radioactivity, different levels of gamma ray log response must be attributed to variances in cement quality. Cement evaluation with tracers can help detect: thin cement sheaths; light-weight or low compressive strength cements where the acoustic impedance is near that of water; gas cut cement where the acoustic signal is attenuated; wells with microannulus that cannot be pressured to obtain valid log data; poor casing centralization; and multiple cement stage placement. The paper describes the logging tool, operational procedures, and a log example.

  16. Studies on Inhibition of Intestinal Absorption of Radioactive Strontium

    PubMed Central

    Paul, T. M.; Edward, Deirdre Waldron; Skoryna, Stanley C.

    1964-01-01

    A method is reported that enables selective suppression of absorption of radioactive strontium from ingested food material, permitting calcium to remain available to the body. Studies were carried out by measuring blood levels and bone uptake of Sr89 and Ca45 at different time intervals after orogastric intubation of rats. The addition of sodium alginate, derived from brown marine algae, to the radioactive isotopes increased the overall physiological discrimination against strontium by amounts up to 60% after 24 hours. This discrimination was further increased by feeding sodium alginate mixed with standard diet in the proportions of 20:80 and 30:70. The observed ratio was reduced by administration of sodium alginate from 0.25 to 0.09. Determination of the limiting dosage in rats is restricted to the amounts which rats will consume. In the event of an inadvertent release of radioactive strontium, human subjects probably could increase their intake of alginate at will, permitting a greater effectiveness of sodium alginate than could be obtained in experimental animals. PMID:14176062

  17. Study of gel materials as radioactive 222Rn gas detectors.

    PubMed

    Espinosa, G; Golzarri, J I; Rickards, J; Gammage, R B

    2006-01-01

    Commercial hair gel material (polyvinyl pyrolydone triethanolamine carbopol in water) and bacteriological agar (phycocolloid extracted from a group of red-purple algae, usually Gelidium sp.) have been studied as radioactive radon gas detectors. The detection method is based on the diffusion of the radioactive gas in the gel material, and the subsequent measurement of trapped products of the natural decay of radon by gamma spectrometry. From the several radon daughters with gamma radiation emission (214Pb, 214Bi, 214Po, 210Pb, 210Po), two elements, 214Pb (0.352 MeV) and 214Bi (0.609 MeV), were chosen for the analysis in this work; in order to determine the best sensitivity, corrections were made for the short half-life of the analysed isotopes. For the gamma spectrometry analysis, a hyperpure germanium solid state detector was used, associated with a PC multichannel analyser card with Maestro and Microsoft Excel software. The results show the viability of the method: a linear response in a wide radon concentration range (450-10,000 Bq m(-3)), reproducibility of data, easy handling and low cost of the gel material. This detection methodology opens new possibilities for measurements of radon and other radioactive gases.

  18. The oceanic geochemistry of artificial radionuclides: The SEEP Project

    SciTech Connect

    Not Available

    1991-01-01

    Radionuclides have been and continue to be introduced to the marine environment in various ways. The atmospheric testing of nuclear weapons in the 1960s resulting in global fallout has been the major contributor of artificial radionuclides to the environment. Nuclear power plants have produced a large quantity of radioactive wastes which are presently being stored on land. The United States, amongst other countries (e.g., England, France, Japan), was seriously investigating the possibility of disposing of these radioactive wastes in the ocean. Clearly it is important to study and to understand the oceanographic behavior of radioactive substances. The DOE sponsored SEEP (Shelf Edge Exchange Processes) research; discussed here, is a detailed study into the biogeochemistry of radionuclides in the shelf and slope environment. The questions asked by this research (see below) pertain directly to problems arising from the introduction of radionuclides into the oceans from energy-related industries (e.g. nuclear power plants, waste disposal).

  19. Using Beads and Divided Containers to Study Kinetic and Equilibrium Isotope Effects in the Laboratory and in the Classroom

    ERIC Educational Resources Information Center

    Campbell, Dean J.; Brewer, Emily R.; Martinez, Keri A.; Fitzjarrald, Tamara J.

    The purpose of this laboratory experiment is to study fundamental concepts of kinetics and equilibria and the isotope effects associated with both of these concepts. The concepts of isotopes in introductory and general chemistry courses are typically used within the contexts of atomic weights and radioactivity. Kinetic and equilibrium isotope…

  20. RadioActive101 Practices

    ERIC Educational Resources Information Center

    Brites, Maria José; Ravenscroft, Andrew; Dellow, James; Rainey, Colin; Jorge, Ana; Santos, Sílvio Correia; Rees, Angela; Auwärter, Andreas; Catalão, Daniel; Balica, Magda; Camilleri, Anthony F.

    2014-01-01

    In keeping with the overarching RadioActive101 (RA101) spirit and ethos, this report is the product of collaborative and joined-up thinking from within the European consortium spread across five countries. As such, it is not simply a single voice reporting on the experiences and knowledge gained during the project. Rather it is a range of…

  1. Radioactive waste: Politics and technology

    SciTech Connect

    Berkhout, F.

    1995-08-01

    This book presents an analysis of the divergent strategies used to forge radioactive waste policies in great Britain, Germany, and Sweden. Some basic knowledge of nuclear technology and its public policy development is needed. The book points out that developing institutional frameworks that permit agreement and consent is the principal challenge of radwaste management and places the problem of consent in an institutional framework.

  2. High-Level Radioactive Waste.

    ERIC Educational Resources Information Center

    Hayden, Howard C.

    1995-01-01

    Presents a method to calculate the amount of high-level radioactive waste by taking into consideration the following factors: the fission process that yields the waste, identification of the waste, the energy required to run a 1-GWe plant for one year, and the uranium mass required to produce that energy. Briefly discusses waste disposal and…

  3. High-Level Radioactive Waste.

    ERIC Educational Resources Information Center

    Hayden, Howard C.

    1995-01-01

    Presents a method to calculate the amount of high-level radioactive waste by taking into consideration the following factors: the fission process that yields the waste, identification of the waste, the energy required to run a 1-GWe plant for one year, and the uranium mass required to produce that energy. Briefly discusses waste disposal and…

  4. STANFORD ARTIFICIAL INTELLIGENCE PROJECT.

    DTIC Science & Technology

    ARTIFICIAL INTELLIGENCE , GAME THEORY, DECISION MAKING, BIONICS, AUTOMATA, SPEECH RECOGNITION, GEOMETRIC FORMS, LEARNING MACHINES, MATHEMATICAL MODELS, PATTERN RECOGNITION, SERVOMECHANISMS, SIMULATION, BIBLIOGRAPHIES.

  5. The artificial womb.

    PubMed

    Bulletti, Carlo; Palagiano, Antonio; Pace, Caterina; Cerni, Angelica; Borini, Andrea; de Ziegler, Dominique

    2011-03-01

    The availability of computer-controlled artificial hearts, kidneys, and lungs, as well as the possibility of implanting human embryos in ex vivo uterus models or an artificial endometrium, presents new perspectives for creating an artificial uterus. Survival rates have also improved, with fetuses surviving from as early as 24 weeks of gestation. These advances bring new opportunities for complete or partial ectogenesis through the creation of an artificial womb, one that could sustain the growth and development of fetuses outside of the human body.

  6. Laser Isotope Separation Employing Condensation Repression

    SciTech Connect

    Eerkens, Jeff W.; Miller, William H.

    2004-09-15

    Molecular laser isotope separation (MLIS) techniques using condensation repression (CR) harvesting are reviewed and compared with atomic vapor laser isotope separation (AVLIS), gaseous diffusion (DIF), ultracentrifuges (UCF), and electromagnetic separations (EMS). Two different CR-MLIS or CRISLA (Condensation Repression Isotope Separation by Laser Activation) approaches have been under investigation at the University of Missouri (MU), one involving supersonic super-cooled free jets and dimer formation, and the other subsonic cold-wall condensation. Both employ mixtures of an isotopomer (e.g. {sup i}QF{sub 6}) and a carrier gas, operated at low temperatures and pressures. Present theories of VT relaxation, dimerization, and condensation are found to be unsatisfactory to explain/predict experimental CRISLA results. They were replaced by fundamentally new models that allow ab-initio calculation of isotope enrichments and predictions of condensation parameters for laser-excited and non-excited vapors which are in good agreement with experiment. Because of supersonic speeds, throughputs for free-jet CRISLA are a thousand times higher than cold-wall CRISLA schemes, and thus preferred for large-quantity Uranium enrichments. For small-quantity separations of (radioactive) medical isotopes, the simpler coldwall CRISLA method may be adequate.

  7. FILTR: Flash Isotope Library and Training Resource

    SciTech Connect

    Campbell, D; Trombino, D

    2007-07-26

    The subject of radiation detection is replete with complex concepts and challenging nomenclature. Furthermore, a daunting variety of radioactive isotopes may be encountered during the routine operation of a radiation detector. Individuals tasked with searching for illicit sources of radiation must remain vigilant while navigating through more frequently encountered mundane and legitimate radioactive sources. The Flash Isotope Library and Training Resource (FILTR) is being developed as an easily accessible and intuitive reference tool to manage the high volume of complex information required for this task. FILTR is an extended version of the Primary Utility for Nuclear Terminology (PUNT) software developed by the Counter Measures Test Beds group at Lawrence Livermore National Laboratory for the United States Secret Service. Authored in the Flash multimedia development environment, FILTR contains detailed information on potentially encountered isotopes as well as training on radiation and operational procedures. Reference material is organized to present critical information quickly while facilitating more in-depth investigation through an intuitive interface and engaging content. FILTR is being developed for a diverse audience of law enforcement organizations and government agencies and a wide range of skill sets from expert analysts to officers whose primary role is not radiation detection. Additionally, the wide compatibility of Flash content will allow FILTR to be readily accessible through the growing number of multi-media enabled electronic devices, including PDAs and cellular phones.

  8. Radioactive Waste Incineration: Status Report

    SciTech Connect

    Diederich, A.R.; Akins, M.J.

    2008-07-01

    Incineration is generally accepted as a method of reducing the volume of radioactive waste. In some cases, the resulting ash may have high concentrations of materials such as Plutonium or Uranium that are valuable materials for recycling. Incineration can also be effective in treating waste that contains hazardous chemicals as well as radioactive contamination. Despite these advantages, the number of operating incinerators currently in the US currently appears to be small and potentially declining. This paper describes technical, regulatory, economic and political factors that affect the selection of incineration as a preferred method of treating radioactive waste. The history of incinerator use at commercial and DOE facilities is summarized, along with the factors that have affected each of the sectors, thus leading to the current set of active incinerator facilities. In summary: Incineration has had a long history of use in radioactive waste processing due to their ability to reduce the volume of the waste while destroying hazardous chemicals and biological material. However, combinations of technical, regulatory, economic and political factors have constrained the overall use of incineration. In both the Government and Private sectors, the trend is to have a limited number of larger incineration facilities that treat wastes from a multiple sites. Each of these sector is now served by only one or two incinerators. Increased use of incineration is not likely unless there is a change in the factors involved, such as a significant increase in the cost of disposal. Medical wastes with low levels of radioactive contamination are being treated effectively at small, local incineration facilities. No trend is expected in this group. (authors)

  9. Method for separating isotopes

    DOEpatents

    Jepson, B.E.

    1975-10-21

    Isotopes are separated by contacting a feed solution containing the isotopes with a cyclic polyether wherein a complex of one isotope is formed with the cyclic polyether, the cyclic polyether complex is extracted from the feed solution, and the isotope is thereafter separated from the cyclic polyether.

  10. Survey of natural and anthropogenic radioactivity in environmental samples from Yugoslavia.

    PubMed

    Esposito, M; Polić, P; Bartolomei, P; Benzi, V; Martellini V; Cvetković, O; Damjanov, V; Simić, M; Zunić, Z; Zivancević, B; Simić, S; Jovanović, V

    2002-01-01

    The radioactivity of 238U, 226Ra, 232Th, 40K and 137Cs in sediments, soil, turf and honey from Serbia and Kosovo (Yugoslavia) was measured using gamma and alpha spectrometry in order to estimate the radiation hazard from natural and man-made sources, as well as to compile a database for radioactivity levels in those regions. One sample, collected in the vicinity of a "depleted uranium" (DU) shell of the recent Balkan war, revealed a high 238U activity and a non-natural 235U/238U activity ratio, confirming therefore its anthropogenic origin. However, some other soil samples coming from characteristic DU craters did not show any characteristic level of radioactivity. The other sediment and turf samples taken all around the country show low radioactivity levels for all the isotopes here considered. With the aim of obtaining some indication about radioactivity migration in the food chain, several honey samples have been examined too. All samples show very low radioactivity content, often indistinguishable from natural background.

  11. Proton-proton correlations observed in two-proton radioactivity of 94Ag.

    PubMed

    Mukha, Ivan; Roeckl, Ernst; Batist, Leonid; Blazhev, Andrey; Döring, Joachim; Grawe, Hubert; Grigorenko, Leonid; Huyse, Mark; Janas, Zenon; Kirchner, Reinhard; La Commara, Marco; Mazzocchi, Chiara; Tabor, Sam L; Van Duppen, Piet

    2006-01-19

    The stability and spontaneous decay of naturally occurring atomic nuclei have been much studied ever since Becquerel discovered natural radioactivity in 1896. In 1960, proton-rich nuclei with an odd or an even atomic number Z were predicted to decay through one- and two-proton radioactivity, respectively. The experimental observation of one-proton radioactivity was first reported in 1982, and two-proton radioactivity has now also been detected by experimentally studying the decay properties of 45Fe (refs 3, 4) and 54Zn (ref. 5). Here we report proton-proton correlations observed during the radioactive decay of a spinning long-lived state of the lightest known isotope of silver, 94Ag, which is known to undergo one-proton decay. We infer from these correlations that the long-lived state must also decay through simultaneous two-proton emission, making 94Ag the first nucleus to exhibit one- as well as two-proton radioactivity. We attribute the two-proton emission behaviour and the unexpectedly large probability for this decay mechanism to a very large deformation of the parent nucleus into a prolate (cigar-like) shape, which facilitates emission of protons either from the same or from opposite ends of the 'cigar'.

  12. Integrated data base report--1996: US spent nuclear fuel and radioactive waste inventories, projections, and characteristics

    SciTech Connect

    1997-12-01

    The Integrated Data Base Program has compiled historic data on inventories and characteristics of both commercial and U.S. Department of Energy (DOE) spent nuclear fuel (SNF) and commercial and U.S. government-owned radioactive wastes. Inventories of most of these materials are reported as of the end of fiscal year (FY) 1996, which is September 30, 1996. Commercial SNF and commercial uranium mill tailings inventories are reported on an end-of-calendar year (CY) basis. All SNF and radioactive waste data reported are based on the most reliable information available from government sources, the open literature, technical reports, and direct contacts. The information forecasted is consistent with the latest DOE/Energy Information Administration (EIA) projections of U.S. commercial nuclear power growth and the expected DOE-related and private industrial and institutional activities. The radioactive materials considered, on a chapter-by-chapter basis, are SNF, high-level waste, transuranic waste, low-level waste, uranium mill tailings, DOE Environmental Restoration Program contaminated environmental media, naturally occurring and accelerator-produced radioactive material, and mixed (hazardous and radioactive) low-level waste. For most of these categories, current and projected inventories are given through FY 2030, and the radioactivity and thermal power are calculated based on reported or estimated isotopic compositions.

  13. Background radioactivity of construction materials, raw substance and ready-made CaMoO4 crystals

    NASA Astrophysics Data System (ADS)

    Busanov, O. A.; Etezov, R. A.; Gavriljuk, Yu. M.; Gezhaev, A. M.; Kazalov, V. V.; Kornoukhov, V. N.; Kuzminov, V. V.; Moseev, P. S.; Panasenko, S. I.; Ratkevich, S. S.; Yakimenko, S. P.

    2014-01-01

    The results of measurements of natural radioactive isotopes content in different source materials of natural and enriched composition used for CaMoO4 scintillation crystal growing are presented. The crystals are to be used in the experiment to search for neutrinoless double beta decay of 100Mo.

  14. Influence of the arrival of radioactive industrially contaminated North Sea water upon the radiation conditions in the Baltic Sea

    SciTech Connect

    Vakulovskii, S.M.; Nikitin, A.I.; Chumichev, V.B.

    1987-08-01

    The authors present and evaluate data from a four-year period of monitoring the movement of radioactive effluents from the radiochemical plants of Western Europe from the North Sea to the Baltic Sea and determine the concentrations at various regions along this pathway for cesium 134 and 137 and strontium 90 isotopes.

  15. 10 CFR 39.47 - Radioactive markers.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 1 2010-01-01 2010-01-01 false Radioactive markers. 39.47 Section 39.47 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Equipment § 39.47 Radioactive markers. The licensee may use radioactive markers in wells only if the individual markers contain...

  16. 10 CFR 39.47 - Radioactive markers.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 1 2011-01-01 2011-01-01 false Radioactive markers. 39.47 Section 39.47 Energy NUCLEAR REGULATORY COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Equipment § 39.47 Radioactive markers. The licensee may use radioactive markers in wells only if the individual markers contain...

  17. 49 CFR 175.705 - Radioactive contamination.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Radioactive contamination. 175.705 Section 175.705... Regulations Applicable According to Classification of Material § 175.705 Radioactive contamination. (a) A... (radioactive) materials that may have been released from their packagings. (b) When contamination is present or...

  18. 46 CFR 148.300 - Radioactive materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Radioactive materials. 148.300 Section 148.300 Shipping... MATERIALS THAT REQUIRE SPECIAL HANDLING Special Requirements for Certain Materials § 148.300 Radioactive materials. (a) Radioactive materials that may be stowed or transported in bulk are limited to those...

  19. 49 CFR 175.705 - Radioactive contamination.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Radioactive contamination. 175.705 Section 175.705... Regulations Applicable According to Classification of Material § 175.705 Radioactive contamination. (a) A... (radioactive) materials that may have been released from their packagings. (b) When contamination is present or...

  20. 46 CFR 147.100 - Radioactive materials.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 5 2011-10-01 2011-10-01 false Radioactive materials. 147.100 Section 147.100 Shipping... Stowage and Other Special Requirements for Particular Materials § 147.100 Radioactive materials. (a) Radioactive materials must not be brought on board, used in any manner, or stored on the vessel, unless the...

  1. 46 CFR 147.100 - Radioactive materials.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 46 Shipping 5 2012-10-01 2012-10-01 false Radioactive materials. 147.100 Section 147.100 Shipping... Stowage and Other Special Requirements for Particular Materials § 147.100 Radioactive materials. (a) Radioactive materials must not be brought on board, used in any manner, or stored on the vessel, unless...

  2. 46 CFR 147.100 - Radioactive materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Radioactive materials. 147.100 Section 147.100 Shipping... Stowage and Other Special Requirements for Particular Materials § 147.100 Radioactive materials. (a) Radioactive materials must not be brought on board, used in any manner, or stored on the vessel, unless...

  3. 46 CFR 147.100 - Radioactive materials.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Radioactive materials. 147.100 Section 147.100 Shipping... Stowage and Other Special Requirements for Particular Materials § 147.100 Radioactive materials. (a) Radioactive materials must not be brought on board, used in any manner, or stored on the vessel, unless...

  4. 46 CFR 148.300 - Radioactive materials.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 5 2013-10-01 2013-10-01 false Radioactive materials. 148.300 Section 148.300 Shipping... MATERIALS THAT REQUIRE SPECIAL HANDLING Special Requirements for Certain Materials § 148.300 Radioactive materials. (a) Radioactive materials that may be stowed or transported in bulk are limited to...

  5. 49 CFR 175.705 - Radioactive contamination.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 2 2012-10-01 2012-10-01 false Radioactive contamination. 175.705 Section 175.705... Regulations Applicable According to Classification of Material § 175.705 Radioactive contamination. (a) A... (radioactive) materials that may have been released from their packagings. (b) When contamination is present...

  6. 49 CFR 175.705 - Radioactive contamination.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 2 2013-10-01 2013-10-01 false Radioactive contamination. 175.705 Section 175.705... Regulations Applicable According to Classification of Material § 175.705 Radioactive contamination. (a) A... (radioactive) materials that may have been released from their packagings. (b) When contamination is present...

  7. 49 CFR 175.705 - Radioactive contamination.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 2 2014-10-01 2014-10-01 false Radioactive contamination. 175.705 Section 175.705... Regulations Applicable According to Classification of Material § 175.705 Radioactive contamination. (a) A... (radioactive) materials that may have been released from their packagings. (b) When contamination is present...

  8. 46 CFR 147.100 - Radioactive materials.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 46 Shipping 5 2014-10-01 2014-10-01 false Radioactive materials. 147.100 Section 147.100 Shipping... Stowage and Other Special Requirements for Particular Materials § 147.100 Radioactive materials. (a) Radioactive materials must not be brought on board, used in any manner, or stored on the vessel, unless...

  9. Radioactive Waste Material From Tapping Natural Resources ...

    EPA Pesticide Factsheets

    2017-08-07

    Rocks around oil and gas and mineral deposits may contain natural radioactivity. Drilling through these rocks and bringing them to the surface creates radioactive waste materials. Once desired minerals have been removed from ore, the radionuclides left in the waste are more concentrated. Scientists call this waste Technologically Enhanced Naturally Occurring Radioactive Material or simply TENORM.

  10. Transporting Radioactive Material | Radiation Protection | US ...

    EPA Pesticide Factsheets

    2017-08-07

    Radioactive material can be transported by truck, train, plane or ship. The shipment of radioactive material has been regulated since 1939. Shipping routes for radioactive materials are picked very carefully and shipments are tracked. Markings on containers and vehicles explain the contents of each package using standard terms and codes.

  11. Changes in the mean square charge radii and electromagnetic moments of neutron-deficient Bi isotopes

    SciTech Connect

    Barzakh, A. E. Batist, L. Kh.; Fedorov, D. V.; Ivanov, V. S.; Molkanov, P. L.; Moroz, F. V.; Orlov, S. Yu.; Panteleev, V. N.; Seliverstov, M. D.; Volkov, Yu. M.

    2015-10-15

    In-source laser spectroscopy experiments for neutron deficient bismuth isotopes at the 306.77 nm atomic transition were carried out at the IRIS (Investigation of Radioactive Isotopes on Synchrocyclotron) facility of Petersburg Nuclear Physics Institute (PNPI). New data on isotope shifts and hyperfine structure for {sup 189–198,} {sup 211}Bi isotopes and isomers were obtained. The changes in the mean-square charge radii and the magnetic moment values were deduced. Marked deviation from the nearly spherical behavior for ground states of bismuth isotopes at N < 109 is demonstrated, in contrast to the lead and thallium isotopic chains. The big isomer shift between I = 1/2 (intruder) and I = 9/2 (normal) states for odd Bi isotopes (A = 193, 195, 197) was found.

  12. Changes in the mean square charge radii and electromagnetic moments of neutron-deficient Bi isotopes

    NASA Astrophysics Data System (ADS)

    Barzakh, A. E.; Batist, L. Kh.; Fedorov, D. V.; Ivanov, V. S.; Molkanov, P. L.; Moroz, F. V.; Orlov, S. Yu.; Panteleev, V. N.; Seliverstov, M. D.; Volkov, Yu. M.

    2015-10-01

    In-source laser spectroscopy experiments for neutron deficient bismuth isotopes at the 306.77 nm atomic transition were carried out at the IRIS (Investigation of Radioactive Isotopes on Synchrocyclotron) facility of Petersburg Nuclear Physics Institute (PNPI). New data on isotope shifts and hyperfine structure for 189-198, 211Bi isotopes and isomers were obtained. The changes in the mean-square charge radii and the magnetic moment values were deduced. Marked deviation from the nearly spherical behavior for ground states of bismuth isotopes at N < 109 is demonstrated, in contrast to the lead and thallium isotopic chains. The big isomer shift between I = 1/2 (intruder) and I = 9/2 (normal) states for odd Bi isotopes (A = 193, 195, 197) was found.

  13. The potential detection of low-level aerosol isotopes from new civilian nuclear processes.

    PubMed

    Miley, H S; Burnett, J L; Foxe, M P; Haas, D A; Keillor, M E; Lowrey, J D; Mayer, M F; McIntyre, J I; Wood, J S

    2017-08-01

    As the world faces a challenging future in maintaining the commercial availability of radioactive isotopes for medical use, new methods of medical isotope production are being pursued. Many of these are small in size and could effectively operate continuously. With the potential for much shorter retention times, a new suite of isotopes may soon be found in the environment. The authors estimate that many more aerosols containing low-level isotopes of gas/volatile origin could be detectable at short range and times, and a few at longer ranges and times as compared to those released in more common nuclear reactor operations. Copyright © 2017. Published by Elsevier Ltd.

  14. Isotope separation by photochromatography

    DOEpatents

    Suslick, K.S.

    1975-10-03

    A photochromatographic method for isotope separation is described. An isotopically mixed molecular species is adsorbed on an adsorptive surface, and the adsorbed molecules are irradiated with radiation of a predetermined wavelength which will selectively excite desired isotopic species. Sufficient energy is transferred to the excited molecules to desorb them from the surface and thus separate them from the undesired isotopic species. The method is particularly applicable to the separation of hydrogen isotopes. (BLM)

  15. Isotope separation by photochromatography

    DOEpatents

    Suslick, Kenneth S.

    1977-01-01

    An isotope separation method which comprises physically adsorbing an isotopically mixed molecular species on an adsorptive surface and irradiating the adsorbed molecules with radiation of a predetermined wavelength which will selectively excite a desired isotopic species. Sufficient energy is transferred to the excited molecules to desorb them from the surface and thereby separate them from the unexcited undesired isotopic species. The method is particularly applicable to the separation of hydrogen isotopes.

  16. EBIS charge breeder for radioactive ion beams at ATLAS.

    SciTech Connect

    Ostroumov, P.; Kondrashev, S.; Pardo, R.; Savard, G.; Vondrasek, R.; Alessi, J.; Beebe, E.; Pikin, A.

    2010-07-01

    The construction of the Californium Rare Isotope Breeder Upgrade (CARIBU) for the Argonne National Laboratory ATLAS facility is completed and its commissioning is being performed. In its full capacity, the CARIBU facility will use fission fragments from a 1 Curie (Ci) {sup 252}Cf source. The ions will be thermalized and collected into a low-energy ion beam by a helium gas catcher, mass analyzed by an isobar separator, and charge bred to higher charge states for acceleration in ATLAS. To reach energies E/A 10 MeV/u, one should inject ions with charge-to-mass ratio (q/A) {ge} 1/7 into the ATLAS linac. In the first stage, the existing Electron Cyclotron Resonance (ECR) ion source will be used as a charge breeder. The maximum intensity of radioactive ion beams at the output of the gas catcher will not exceed 10{sup 7} ions per second. A charge breeder based on an Electron Beam Ion Source (EBIS) has significant advantages over the ECR option for ion beam intensities up to about 10{sup 9} ions per second, providing 3-4 times higher efficiency and significantly better purity of highly charged radioactive ion beams for further acceleration. The proposed EBIS project for CARIBU will heavily utilize state-of-the-art EBIS technology recently developed at Brookhaven National Laboratory. This will allow us to reduce both the project cost and timescale, simultaneously insuring reliable technical realization of the cutting-edge technology. Several parameters of the CARIBU EBIS charge breeder (EBIS-CB) will be relaxed with respect to the BNL EBIS in favor of higher reliability and lower cost. Technical performance of the CARIBU charge breeder will not suffer from such a relaxation and will provide high efficiency for a whole range of radioactive ion beams. The goal of this paper is to present the initial design of the EBIS charge breeder for radioactive ion beams at ATLAS.

  17. EBIS charge breeder for radioactive ion beams at ATLAS

    NASA Astrophysics Data System (ADS)

    Ostroumov, P.; Kondrashev, S.; Pardo, R.; Savard, G.; Vondrasek, R.; Alessi, J.; Beebe, E.; Pikin, A.

    2010-07-01

    The construction of the Californium Rare Isotope Breeder Upgrade (CARIBU) for the Argonne National Laboratory ATLAS facility is completed and its commissioning is being performed. In its full capacity, the CARIBU facility will use fission fragments from a 1 Curie (Ci) 252Cf source. The ions will be thermalized and collected into a low-energy ion beam by a helium gas catcher, mass analyzed by an isobar separator, and charge bred to higher charge states for acceleration in ATLAS. To reach energies E/A 10 MeV/u, one should inject ions with charge-to-mass ratio (q/A) >= 1/7 into the ATLAS linac. In the first stage, the existing Electron Cyclotron Resonance (ECR) ion source will be used as a charge breeder. The maximum intensity of radioactive ion beams at the output of the gas catcher will not exceed 107 ions per second. A charge breeder based on an Electron Beam Ion Source (EBIS) has significant advantages over the ECR option for ion beam intensities up to about 109 ions per second, providing 3-4 times higher efficiency and significantly better purity of highly charged radioactive ion beams for further acceleration. The proposed EBIS project for CARIBU will heavily utilize state-of-the-art EBIS technology recently developed at Brookhaven National Laboratory. This will allow us to reduce both the project cost and timescale, simultaneously insuring reliable technical realization of the cutting-edge technology. Several parameters of the CARIBU EBIS charge breeder (EBIS-CB) will be relaxed with respect to the BNL EBIS in favor of higher reliability and lower cost. Technical performance of the CARIBU charge breeder will not suffer from such a relaxation and will provide high efficiency for a whole range of radioactive ion beams. The goal of this paper is to present the initial design of the EBIS charge breeder for radioactive ion beams at ATLAS.

  18. EBIS charge breeder for radioactive ion beams at ATLAS

    SciTech Connect

    Ostroumov, P.; Alessi, J.; Kondrashev, S.; Pardo, R.; Savard, G.; Vondrasek, R.; Beebe, E.; Pikin, A.

    2010-07-20

    The construction of the Californium Rare Isotope Breeder Upgrade (CARIBU) for the Argonne National Laboratory ATLAS facility is completed and its commissioning is being performed. In its full capacity, the CARIBU facility will use fission fragments from a 1 Curie (Ci) {sup 252}Cf source. The ions will be thermalized and collected into a low-energy ion beam by a helium gas catcher, mass analyzed by an isobar separator, and charge bred to higher charge states for acceleration in ATLAS. To reach energies E/A 10 MeV/u, one should inject ions with charge-to-mass ratio (q/A) {ge} 1/7 into the ATLAS linac. In the first stage, the existing Electron Cyclotron Resonance (ECR) ion source will be used as a charge breeder. The maximum intensity of radioactive ion beams at the output of the gas catcher will not exceed 10{sup 7} ions per second. A charge breeder based on an Electron Beam Ion Source (EBIS) has significant advantages over the ECR option for ion beam intensities up to about 10{sup 9} ions per second, providing 3-4 times higher efficiency and significantly better purity of highly charged radioactive ion beams for further acceleration. The proposed EBIS project for CARIBU will heavily utilize state-of-the-art EBIS technology recently developed at Brookhaven National Laboratory. This will allow us to reduce both the project cost and timescale, simultaneously insuring reliable technical realization of the cutting-edge technology. Several parameters of the CARIBU EBIS charge breeder (EBIS-CB) will be relaxed with respect to the BNL EBIS in favor of higher reliability and lower cost. Technical performance of the CARIBU charge breeder will not suffer from such a relaxation and will provide high efficiency for a whole range of radioactive ion beams. The goal of this paper is to present the initial design of the EBIS charge breeder for radioactive ion beams at ATLAS.

  19. Artificial insemination in poultry

    USDA-ARS?s Scientific Manuscript database

    Artificial insemination is a relative simple yet powerful tool geneticists can employ for the propagation of economically important traits in livestock and poultry. In this chapter, we address the fundamental methods of the artificial insemination of poultry, including semen collection, semen evalu...

  20. Artificial intelligence: Recent developments

    SciTech Connect

    Not Available

    1987-01-01

    This book presents the papers given at a conference on artificial intelligence. Topics considered at the conference included knowledge representation for expert systems, the use of robots in underwater vehicles for resource management, precision logic, an expert system for arc welding, data base management, a knowledge based approach to fault trees, and computer-aided manufacturing using simulation combined with artificial intelligence.