WorldWideScience

Sample records for radioactivity artificially induced

  1. 3 Artificial environmental radioactivity

    International Nuclear Information System (INIS)

    Nuclear explosions re an important source of artificial radionuclides. In addition to nuclear fission, radionuclides are produced by interaction of emitted neutrons with atomic nuclei of the ambient atmosphere, soil and water. The production is described of some radionuclides (T, 14C, 85Kr, 89Sr, 90Sr, 137Cs, 131I, 133I, transuranium elements) contained in radioactive fallout. Basic information is given on the mining and processing of uranium ores, on nuclear reactors and radionuclides produced in chain reactions. The causes are analyzed of accidents which led to environmental contamination. (J.C.)

  2. Artificial radioactivity in the sea. Chapter 22

    International Nuclear Information System (INIS)

    The subject is covered in sections, entitled: global inventory of artificially produced radionuclides (including fallout and controlled disposal of radioactive wastes from nuclear power production); radioactivity as a potential pollutant (including public health implications of discharges from selected sites); radiation dose commitment to marine organisms; spectrum of artificially-produced radionuclides in marine environments and their overall distribution; distribution of radionuclides in seawater; distribution of radionuclides in sediment; bioaccumulation. (U.K.)

  3. Induced radioactivity at CERN

    CERN Multimedia

    1970-01-01

    A description of some of the problems and some of the advantages associated with the phenomenon of induced radioactivity at accelerator centres such as CERN. The author has worked in this field for several years and has recently written a book 'Induced Radioactivity' published by North-Holland.

  4. Artificial radioactivity is fifty: 1934-1984

    International Nuclear Information System (INIS)

    This book has been published on the occasion of the fiftieth anniversary celebration of the artificial radioactivity discovery; contributions from men who have been near the Joliot at the beginning of the artificial radioactivity, or whose work have been marked by this discovery are gathered in this book. Subjects have been choosed very freely by the authors; that explains their great diversity. The reader will find precious memories from direct witnesses of this great time; he will find also descriptions of the following works; he will even find audacious dreams on matter utilization possibilities, which may rise to-morrow

  5. Artificial radioactivity in the Cumbrian environment

    International Nuclear Information System (INIS)

    An extended abstract is given of a paper on the distribution of artificial radioactivity in the environment of the British Nuclear Fuels Ltd plant at Sellafield. Brief reports are given of soil surveys, coastal surveys and transects and measurements of levels of radio-nuclides in airborne and deposited material. The discussion which followed the presentation of the paper is included. (U.K.)

  6. Natural and artificial radioactivity in food

    International Nuclear Information System (INIS)

    By far the largest fraction of the radiation dose to the population stems from artificial radiactivity used for medical purposes (42 p.c.); the next ranking source is the Rn-222 in building materials (29 p.c.), and the third fraction is contributed by cosmic and natural radioactivity in the environment. The main sources of the body burden are K-40 and C-14. The radionuclide composition in the human body can be modified by nuclear weapons tests, reactor accidents like the one in Chernobyl, and operation of nuclear facilities, with radioactivity uptake via the food chain playing a special role. The author explains the contribution of radioactivity in food to the population exposure. (DG)

  7. Digital monitor of artificial radioactive aerosols

    International Nuclear Information System (INIS)

    The new digital monitor KOPR 06 is fitted with the latest electronic components allowing more reliable operation of the instrument. A conventional device is completed with a digital monitor of artificial alpha radioactivity operating in optimal mode. This will eliminate the shortfall of analog aerosol gauges, namely the constant monitoring level. SYNPOR filters 100 mm in diameter are used for trapping radioactive aerosols. A scintillation probe 80 mm in diameter with a ZnS scintillator is used for alpha detection and a Geiger-Mueller tube of the SI 8 B type is used for detecting beta radiation. The device is provided with an automatic flow rate controller. (E.S.). 4 figs., 4 refs

  8. 16. Analysis of artificial radioactive materials

    International Nuclear Information System (INIS)

    The methods of artificial radionuclide determination and identification are reviewed and characterized. The analyses and separation techniques of fission products and transuranium elements are discussed in more detail. (M.D.)

  9. Plasmon-induced artificial photosynthesis.

    Science.gov (United States)

    Ueno, Kosei; Oshikiri, Tomoya; Shi, Xu; Zhong, Yuqing; Misawa, Hiroaki

    2015-06-01

    We have successfully developed a plasmon-induced artificial photosynthesis system that uses a gold nanoparticle-loaded oxide semiconductor electrode to produce useful chemical energy as hydrogen and ammonia. The most important feature of this system is that both sides of a strontium titanate single-crystal substrate are used without an electrochemical apparatus. Plasmon-induced water splitting occurred even with a minimum chemical bias of 0.23 V owing to the plasmonic effects based on the efficient oxidation of water and the use of platinum as a co-catalyst for reduction. Photocurrent measurements were performed to determine the electron transfer between the gold nanoparticles and the oxide semiconductor. The efficiency of water oxidation was determined through spectroelectrochemical experiments aimed at elucidating the electron density in the gold nanoparticles. A set-up similar to the water-splitting system was used to synthesize ammonia via nitrogen fixation using ruthenium instead of platinum as a co-catalyst. PMID:26052419

  10. Natural and artificial radioactivity levels in sediments in Algiers bay

    International Nuclear Information System (INIS)

    Natural (238U and 232Th series, 40K) and artificial (137Cs) radioactivity levels in the sediments of Algiers bay were measured using gamma-ray spectrometry. Concentrations (Bq kg-1, dry weight) have been observed to range from 10.8 to 25.0 for 238U, from 6.5 to 31.7 for 232Th, from 55.9 to 607.4 for 40K and from 0.95 to 9.5 for 137Cs. These values are discussed in terms of the facies type of the sea bottom. (Author)

  11. Modelling of artificial radioactivity migration in environment: a survey

    International Nuclear Information System (INIS)

    The aim of this report is to present a compilation and description of models to assess the environmental behaviour and effects of accidental and routine releases of artificial radioactivity from nuclear power facilities. About 60 models are described and a card is given for each one, to indicate in summarized form its features and data content. This collection is intended to help in developing specific personal models by assembling different parts chosen among the most suitable ones of different models of various degrees of sophistication

  12. Medical imaging was boosted by the discovery of artificial radioactivity

    International Nuclear Information System (INIS)

    This article draws the history of medical imaging since the discovery of artificial radioactivity in 1934. The author reviews the PET (positron emission tomography) and MRI (magnetic resonance imaging) technologies and presents the recent progress in neuro-sciences that have been made possible by using these 2 technologies. Brain imaging has allowed to show: - the impact of emotions on logical mental processes and on mental performances, - the management of memory in the brain of talented quick reckoners, - the degeneration of neurons, and - the link between autism and the presence of structural and functional anomalies in the brain. (A.C.)

  13. Natural and artificial radioactivity in the Svalbard glaciers

    International Nuclear Information System (INIS)

    Natural and artificial radioactivity in the snow of 10 Svalbard glaciers has been measured from 31 ice core samples, drilled between 1981 and 1993. Of these ice cores, seven exhibit the well-known level arising from the fallout of the 1961-62 atmospheric thermonuclear tests. The second level, due to the Chernobyl accident (26 April 1986), has been detected in all the studied glaciers; the maximum 137Cs fallout reaches 22 Bq kg-1 and shows a high variability. The natural radioactivity, mostly due to 210Pb, shows an in-depth variation which is not governed by its half-life (22.2 years). These measurements serve many glaciological purposes: absolute dating of the snow layers; air-snow transfer and fallout studies; the determination of mean annual mass balances in the accumulation area of glaciers and their associated spatio-temporal variations. (author)

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

    International Nuclear Information System (INIS)

    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

  15. Radioactivity of natural and artificial building materials – a comparative study

    International Nuclear Information System (INIS)

    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 226Ra, 232Th and 40K 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 226Ra content. Natural, i.e. adobe and also brick samples contain higher amount of 40K 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 to the limitations of the internal hazard considerations based on only measured 226Ra activity concentrations without direct radon measurements. Our data are compared to those obtained in other countries and they provide a good basis to expand the database of radioactivity of building materials and gives information about the safety and situation of the building material industry in this central region of Europe. -- Highlights: ? Radionuclide content and various hazard indices of 40 building materials are studied. ? Data are compared to each other and to results obtained in other studies. ? Radon hazard portion is defined. ? Seven samples exceed any of the thresholds, but three is considered to be hazardous

  16. Evaluation of induced radioactivity in irradiated foods

    International Nuclear Information System (INIS)

    This report was made by Japanese Research Association For Food Irradiation from the minutes of Masakazu FURUTA's lecture in the third Food Irradiation Subcommittee of Atomic Energy Commission. Masakazu FURUTA published that the induced radioactivity of food by gamma-ray of Co-60 or Ce-137, 5 MeV X-ray and 10 MeV electron beam was out of question from evaluating the values of literature by theoretical calculation. The induced radioactivity in pepper irradiated by gamma-ray of Co-60 or Ce-137, 5 MeV X-ray and 10 MeV electron beam showed lower values than natural radiation. The induced radioactivity in the food irradiated, evaluation of generation of nuclear reactions, the theoretical evaluation method of induced radioactivity, and evaluation of irradiated radioactivity in irradiated peppers are described. (S.Y.)

  17. Artificial radioactivity in the environmental samples as IAEA reference materials

    International Nuclear Information System (INIS)

    Radioactivity levels of 110mAg, 241Am, 60Co, 134Cs, 137Cs, 106Ru, 125Sb in some biological and environmental materials have been determined by gamma-ray spectrometry in the frame of 15 intercomparison runs organized by IAEA during 1986-1995. The investigated materials were polluted by various nuclear activities, as follows: 1. Nuclear experiments: IAEA-367, sediment collected in 1982 at the Enewetak Atoll (Marshall Islands in the Pacific Ocean). This atoll was used by the USA during 1948-1958 to test nuclear devices; IAEA-368, sediment collected in June 1989 from the Pacific Ocean at the Mururoa Atoll. Since 1966 this atoll has been used by France to test different nuclear devices. 2. Nuclear installations: IAEA-134, cockle flesh of Cardium edule collected in March 1991 from the Irish Sea (Morecambe Bay), England, about 45 km S-E of Sellafield radioactive discharge; IAEA-135, sediment collected in July 1991 in Lune Estuary-England. This area is influenced by the radioactive discharges of the nuclear installations of Sellafield; IAEA-326, soil collected in 1990 in the region of Kursk Atomic Power Plant (Russia). 3. Nuclear accidents (Chernobyl): IAEA-306, sediment collected in the Baltic Sea during October-November 1986; IAEA-307, seaplant Posidonia oceanica, collected in October 1986 in Mediterranean Sea along the shore, in the vicinity of the Principality of Monaco; IAEA-308, mixed seaweeds collected in October 1986 in Mediterranean Sea along the shore, in the vicinity of the Principality of Monaco; IAEA-156, clover collected during the summer harvest 1986 in Austria; IAEA-321, milk powder collected in autumn 1987 from a processing plant in Europe; IAEA-352, tuna fish flesh collected in April 1988 in the Western Mediterranean Sea; IAEA-373, grass collected from Kiev region during the summer harvest 1990; IAEA-375, soil collected in July 1990 from Brjansk region, Russia; IAEA-300, sediment collected in July 1992 in Bothnian Sea (Baltic Sea). 4. Uncontaminated by nuclear activities: IAEA-327, Podsolic soil collected in 1990 from the Moscow region and considered uncontaminated by radionuclides of the Chernobyl accident or by other nuclear activities. The results obtained by our laboratory are in good agreement with the certified IAEA data. Generally, the concentration of the artificial radionuclides in the investigated samples is higher than that expected from the influence of global fallout in the intercomparison materials distributed before Chernobyl accident. Concerning the nature of these investigated IAEA reference materials, very high values for the concentration levels of cesium radionuclides especially in IAEA-373 (grass) and IAEA-375 (soil) samples collected in the vicinity of Chernobyl Power Station after the nuclear accident in 1986 were found. High levels of radioactivities for the artificial radionuclides were also determined in the samples collected in the neighbourhood of the nuclear installations, especially in marine sediment (IAEA-135). It is of interest to point out the high concentration of cesium radionuclides in IAEA-300 sediment collected in 1992 in the Baltic Sea in comparison with the IAEA-306 sediment collected also in the Baltic Sea in 1986. It seems to be an increase of the Baltic Sea artificial radioactivity by accumulation in time. Marine sediment constitutes an important component of marine ecosystem since it represents the final sink for any releases of wastes into the sea. These certified radioactive materials are very useful to all laboratories engaged in the radioactive pollution investigations on environmental samples. (authors)

  18. Artificial radioactivity on the coasts of Northern Ireland

    International Nuclear Information System (INIS)

    In Northern Ireland, measurements of artificial radioactivity have been made in inshore seawater, beach sand and mud, sea spray, the air and material deposited from the air, and in coastal soil. The objective was to determine the levels in the coastal environment and also to assess the magnitude of transport of radioactivity from sea to land in sea spray. The results would provide a basis for the development of a model describing sea to land transfer, and allowing the resulting population exposure to be assessed. The results showed the presence of plutonium isotopes, 241Am and 137Cs in some samples of each of the media measured, but concentrations were low in all cases. Large variation in the concentrations in seawater and beach sediment were attributed to variations in dispersion and in the characteristics of the sediment. Sea to land transfer of actinides was detected in samples of sea spray and in air and deposition measurements. Only at some sites on the east coast could the resulting accumulation in soil close to the beach be distinguished from fallout. Following May 1986 137Cs from Chernobyl could be detected in air and in atmospheric deposition. A preliminary assessment of the exposure of the population to the actinides and 137Cs in all the media showed that the resulting dose is a small fraction of the recognised limit. (author)

  19. Current progress in research of natural and artificial radioactivity in surface waters

    International Nuclear Information System (INIS)

    With the development of nuclear energy production, rare-earth element industry and use of radioactive sources, potential possibility of radiation contamination exits. Analysis of natural and artificial radioactivity in waters was carried out in order to protect our environment and public health. Current progress in research of radioactivity in surface waters will be viewed in the article. (authors)

  20. Induced radioactivity in the vacuum chamber

    CERN Document Server

    Wigmans, R

    2001-01-01

    In this note, I estimate the levels of the radioactivity induced in the LHCb vertex chamber. Interactions induced by neutrons are the main contributors to this effect. A comparison is made between the effects in chambers made of steel and of aluminium.

  1. Nuclear chemistry fifty years after the discovery of artificial radioactivity

    International Nuclear Information System (INIS)

    In January 1934, the observation and the chemical identification of radiophosphorus as a reaction product in the bombardment of Aluminium by alpha particles have been the first step of a new scientific branch: Nuclear Chemistry. We describe here how this discovery in itself contains the frame of all the development which has followed. It consisted in four stages, each of them being a crucial starting point. The first one is the possibility for a total balance of the nuclear reaction in the exit channels, so that reaction mechanisms can be studied. The second, the most important perhaps, is the opening of nuclear synthesis. Nuclear chemists can now interfere into nuclear matter and instead of staying as observers of the radioactive decays of natural isotopes, they were able to build up a numerous chart of various nuclear species, going step by step further and further away from the nuclear stability conditions. The third aspect of the discovery was the appearance of a new mode of radioactive decay with the production of the first particle an antimater. 50 years later, the instability due to a much larger excess of protons is known to induce the proton emission radioactivity for new species like 109I or 115Cs, in the vicinity of proton unstability. Finally, the last point, so fertile for the future, was the observation of a neutron in the exit channel, so that neutron fluxes could result from alpha induced nuclear reactions and became such a strong tool for the production of transuranium elements and for nuclear fission. In the present survey, the wide interest of the second point, i.e. the nuclear synthesis, is emphasized, as well as the huge change in the technical methods

  2. Natural and induced radioactivity in food

    International Nuclear Information System (INIS)

    One of the first questions often asked about irradiated food is whether it is radioactive. Not many people understand that food and any natural substance contains natural radioactivity which can be measurable. It is therefore important to put the issue on natural radioactivity and possible induced radioactivity in food in perspective. While there is a clear consensus among the scientific community that no radioactivity is induced when food is irradiated by gamma rays from cobalt-60 or cesium-137, electron generated by a machine with energy less than 10 million electron volt (MeV) or X rays produced generated by a machine with energy less than 5 MeV. However, data to this effect were published many years ago and are not easy to find. As food irradiation is gaining wide acceptance in many countries, it was considered timely to compile data on natural and induced radioactivity in food into one document. We are grateful to A. Brynjolfsson, one of the few experts who have the knowledge on this subject as well as wide experience on food irradiation, who collected, compiled and evaluated all data on this subject into one report. This publication provides clear explanations not only why radioactivity cannot be induced in food irradiated by radiation sources mentioned above but to what extent the increase in dose or energy level of radiation sources would induce significantly radioactivity in food. The compilation of such data was prompted by a desire to increase the energy limit and the absorbed dose based on the need to irradiate thicker samples of food and to use sterilizing dose up to 60 kGy. This publication concluded that the increase in radiation background dose from consumption of food irradiated to an average dose up to 60 kGy with gamma rays from cobalt- 60 or cesium-137, with 10 MeV electrons or with 5 MeV X rays is insignificant. In addition, food irradiated with X ray with energy up to 7.5 MeV to a dose of 30 kGy has radioactivity well below natural radioactivity in unirradiated food. There are no adverse effect from consumption of irradiated food which contains radioactivity well below background level. This publication should provide valuable information to anyone who has interest in food irradiation especially regulatory authorities for food safety and radiation applications as well as to consumers who might be interested in scientific matters of irradiated food

  3. Natural and artificial radioactivity determination of some medicinal plants

    Energy Technology Data Exchange (ETDEWEB)

    Desideri, Donatella, E-mail: donatella.desideri@uniurb.i [Institute of General Chemistry, Urbino University ' Carlo Bo' , Piazza Rinascimento 6, 61029 Urbino (Italy); Meli, Maria Assunta; Roselli, Carla [Institute of General Chemistry, Urbino University ' Carlo Bo' , Piazza Rinascimento 6, 61029 Urbino (Italy)

    2010-09-15

    Several medicinal plants used in Italy were analysed to determine natural and artificial radioactivity in those parts (leaves, fruits, seeds, roots, peduncles, flowers, barks, berries, thallus) used generally as remedies. The radionuclides were determined by alpha ({sup 238}U, {sup 210}Po) and gamma ({sup 214}Pb-Bi, {sup 210}Pb, {sup 40}K and {sup 137}Cs) spectrometry. {sup 238}U ranged between <0.1 and 7.32 Bq kg{sub dry}{sup -1}; {sup 210}Po between <0.1 and 30.3 Bq kg{sub dry}{sup -1}; {sup 214}Pb-{sup 214}Bi between <0.3 and 16.6 Bq kg{sub dry}{sup -1}; {sup 210}Pb between <3 and 58.3 Bq kg{sub dry}{sup -1}; {sup 40}K between 66.2 and 3582.0 Bq kg{sub dry}{sup -1}; {sup 137}Cs between <0.3 and 10.7 Bq kg{sub dry}{sup -1}. The percentage of {sup 210}Po extraction in infusion and decoction was also determined; the arithmetical mean value of percentage of {sup 210}Po extraction resulted 20.7 {+-} 7.5.

  4. Artificial radioactivity in tide washed pastures in south west Scotland

    International Nuclear Information System (INIS)

    A study has been carried out to determine the impact of Sellafield discharges on the levels of radioactivity in tide washed pastures in south west Scotland. The likely areas of tidal inundations along the Nith, Urr, Dee, Fleet and Cree (including nearby Bladnoch) rivers were assessed using maps and aerials photographs. These were then visited and gamma radiation measurements taken at regular intervals to enable the external dose from anthropogenic nuclides to be estimated. A further survey followed where soil cores were taken from the areas on each river where the external dose appeared highest and analysed for a range of artificial radionuclides. The levels of 137Cs, 134Cs, 238Pu, 239+240Pu and 241Am found, although small, were clearly in excess of the background from other sources. A habit survey was carried out to provide site specific information of tide washed pasture usage, which, with the spatial radionuclide data was used to estimate doses to appropriate critical groups. The maximum annual dose calculated to arise was 60 ?Sv which is less than 6% of the ICRP principal dose limit of 1 mSv. (author)

  5. Investigation and assessment on artificial radioactivity level in waters in Shanghai

    International Nuclear Information System (INIS)

    Investigation and assessment on artificial radioactivity level in river, lake, reservoir and tap waters in Shanghai from 1989?1991 have been done. Totally 45 samples from 15 measuring sites in dry and wet seasons were collected. The results showed that the radioactivity level of various water bodies in Shanghai were within normal background value

  6. Natural and artificial levels of radioactivity in soil of Campania region

    International Nuclear Information System (INIS)

    The ground radioactivity is generally ascribed to the natural radiation present in soil and, the artificial radionuclides originated by nuclear weapons tests, accidental releases from nuclear power and industrial plants. The redistribution of natural radioactivity related to agricultural management and the use of fertilizers presenting a high concentration of radioelements must be also considered. The aim of the present work was to investigate the various components of the ground radioactivity in Campania, a region of Italy, including the recent Chernobyl fall out

  7. Induced radioactivity due to high energy radiation

    International Nuclear Information System (INIS)

    In high energy radiation facilities, the reaction called ''Spallation'' (nuclear spallation) becomes to contribute greatly to the production of induced radioactivity in the facility structures, water and air, besides thermal neutron capture reaction and the reaction accompanied by nucleon release due to fast neutrons. Spallation products have three features. The first is the abundance of the kinds of nuclides produced, the second is that the major part of the products are positron emitters, and the third is that the most products have short life. If the estimation of the radioactivity intensity and amount of spallation products is intended from the viewpoint of radiation protection, experimental values or the semi-empirical equation determined on the basis of experimental values should be used. Rudstam formula is well-known as such a semi-empirical equation. Though it is important for health physics to estimate the induced activity production due to high energy radiation quantitatively and as accurately as possible, the quantitative estimation is practically quite difficult. The problems in radiation control caused by induced activity include the spatial dose rate in operation and during shut down, the radioactive contamination of workers and the treatment and disposal of activated water and air. It is necessary in the actual radiation control duties to develop the monitoring techniques or radioactivity concentration, because the routine monitoring techniques seem to have not yet been established, and the calibration and assessment procedures seem to leave room for the improvement. (Wakatsuki, Y.)

  8. Daily measurements of natural and artificial radioactivity in 1962

    International Nuclear Information System (INIS)

    Daily numerical results of measures concerning ? activity of the air, either from natural, owing to thoron, of from artificial, owing to active aerosols origin, will be found in this statement. The all results are expressed in ??curie/m3 of air. Proceedings of measure and technic of standardization, which were the matter of anterior papers, have not been discussed once more here. (author)

  9. Daily measurements of natural and artificial radioactivity in 1960

    International Nuclear Information System (INIS)

    Daily numerical results of measures concerning ? activity of the air, either from natural, owing to thoron, or from artificial, owing to active aerosols origin, will be found in this statement. The all results are expressed in ??curie / m3 of air. Proceedings of measure and technic of standardization, which were the matter of anterior papers, have not been discussed once more here. (author)

  10. Natural and artificial alpha radioactivity of platinum isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Tavares, O A P; Medeiros, E L, E-mail: emil@cbpf.br [Centro Brasileiro de Pesquisas Fisicas-CBPF/MCT, Rua Dr Xavier Sigaud 150, 22290-180 Rio de Janeiro-RJ (Brazil)

    2011-10-15

    The partial alpha emission half-life for the naturally occurring and artificially produced platinum isotopes (Z=78) was evaluated in the framework of a semiempirical, one-parameter model based on the quantum mechanical tunneling mechanism through a Coulomb-plus-centrifugal-plus-overlapping potential barrier within the spherical nucleus approximation. This approach has been shown to be exceptionally well suited (to a level of 90% of the cases within a factor of less than 2) to fitting the existing data covering nearly 23 orders of magnitude in the measured half-lives. Exceptions were found for the artificial alpha transition from {sup 176}Pt to the excited level of {sup 172}Os, and the rare, quite recently observed, case of the natural alpha decay of {sup 190}Pt to the first excited level of {sup 186}Os. Comparison with other alpha decay half-life estimates for the naturally occurring platinum isotopes has also been presented.

  11. Metal Complexes Containing Natural and and Artificial Radioactive Elements and Their Applications

    OpenAIRE

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

    2014-01-01

    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 ?-organometallics are discussed from the view point of their synthesis, properties, and main application...

  12. Artificial intelligence methods applied for quantitative analysis of natural radioactive sources

    International Nuclear Information System (INIS)

    Highlights: ? Basic description of artificial neural networks. ? Natural gamma ray sources and problem of detections. ? Application of neural network for peak detection and activity determination. - Abstract: Artificial neural network (ANN) represents one of artificial intelligence methods in the field of modeling and uncertainty in different applications. The objective of the proposed work was focused to apply ANN to identify isotopes and to predict uncertainties of their activities of some natural radioactive sources. The method was tested for analyzing gamma-ray spectra emitted from natural radionuclides in soil samples detected by a high-resolution gamma-ray spectrometry based on HPGe (high purity germanium). The principle of the suggested method is described, including, relevant input parameters definition, input data scaling and networks training. It is clear that there is satisfactory agreement between obtained and predicted results using neural network.

  13. Evaluation of induced radioactivity in 10 MeV-Electron irradiated spices, (2); [beta]-ray counting

    Energy Technology Data Exchange (ETDEWEB)

    Katayama, Tadashi; Furuta, Masakazu; Shibata, Setsuko; Matsunami, Tadao; Ito, Norio; Mizohata, Akira; Toratani, Hirokazu (Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology); Takeda, Atsuhiko

    1994-02-01

    In order to check radioactivity of beta-emmitters produced by ([gamma], n) reactions which could occur at energies up to 10 MeV, black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electron from a linear accelerator to a dose of 100 kGy. Beta-rays were counted using a 2[pi] gas flow counter and a liquid scintillation counter. Any induced radioactivity could not be detected in irradiated samples. When inorganic compounds containing the nuclides in the list were artificially added in the samples and were irradiated, the [beta]-activities were detected. From the amount of observed radioactivities of [beta]-emmitters produced in the compounds as photonuclear products, it is concluded that the induced radioactivity in natural samples by 10 MeV-electron irradiation were far smaller than natural radioactivity from [sup 40]K contained in the samples and, hence, its biological effects should be negligible. (author).

  14. Application of two-barrier model of radioactive agent transport in sea water for analyzing artificial radionuclide release from containers with radioactive waste dumped in Kara Sea

    International Nuclear Information System (INIS)

    Modeling of artificial radionuclide transport in sea water is crucial for prognosis of radioecological situation in regions where dumping of radioactive waste had been made and/or accidents with nuclear submarines had taken place. Distribution of artificial radionuclides in bottom sediments can be a detector of radionuclide release from dumped or sunk objects to marine environment. Proper model can determine the dependence between radionuclide distribution in sediments and radionuclide release. Following report describes two-barrier model of radioactive agent transport in sea water. It was tested on data from 1994 - 2013 expeditions to Novaya Zemlya bays, where regular dumping of solid radioactive waste was practiced by the former USSR from the early 1960's until 1990. Two-barrier model agrees with experimental data and allows more accurate determination of time and intensity of artificial radionuclide release from dumped containers. (authors)

  15. Results of concentration measurements of artificial radioactive aerosols in the lower atmosphere

    International Nuclear Information System (INIS)

    This report gives the results of the measurements of artificial gross-?-radioactivity in aerosols in the lower atmosphere; these measurements have been made by the Electronic Physics Service of the Electronic Department, and by the Atmospheric Physics Laboratory of the Paris Science Faculty. The measurements were begun in September 1956 and were continued in an increasing number of stations both in France and in the rest of the world. The present report deals with the period up to the end of august 1961, that is up to the end of the nuclear moratorium. After recalling the constitution and the properties of radioactive aerosols present in the atmosphere, the authors describe the measurement methods, estimate their accuracy and discuss various aspects of the results. (authors)

  16. Artificial neural network application in isotopic characterization of radioactive waste drums

    International Nuclear Information System (INIS)

    One of the most important aspects to the development of the nuclear technology is the safe management of the radioactive waste arising from several stages of the nuclear fuel cycles, as well as from production and use of radioisotope in the medicine, industry and research centers. The accurate characterization of this waste is not a simple task, given to its diversity in isotopic composition and non homogeneity in the space distribution and mass density. In this work it was developed a methodology for quantification and localization of radionuclides not non homogeneously distributed in a 200 liters drum based in the Monte Carlo Method and Artificial Neural Network (RNA), for application in the isotopic characterization of the stored radioactive waste at IPEN. Theoretical arrangements had been constructed involving the division of the radioactive waste drum in some units or cells and some possible configurations of source intensities. Beyond the determination of the detection positions, the respective detection efficiencies for each position in function of each cell of the drum had been obtained. After the construction and the training of the RNA's for each developed theoretical arrangement, the validation of the method were carried out for the two arrangements that had presented the best performance. The results obtained show that the methodology developed in this study could be an effective tool for isotopic characterization of radioactive wastes contained in many kind of packages. (author)

  17. Man-made radioactivity

    International Nuclear Information System (INIS)

    Productions and types of artificial radioactive materials generated for various applications are discussed in this chapter. Newly discovered radioactive materials deriving from fission products are also included. The following subjects are covered: nuclear reactions- notation of reactions, charge particle induced reaction, neutron induced reaction, neutron generators, reaction mechanism; species of radioisotopes - from (n,?), (n,f), charge particles induced reactions, carrier free radioisotopes, artificial elements - technetium group, transuranium elements; rate of production, radionuclides in environment via nuclear explosion, fuel reprocessing, nuclear reactors and nuclear accident. The radioactive materials found in consumer products which are not cover and control by the acts and regulation are also discussed briefly. (Author)

  18. Fusion Induced by Radioactive Ion Beams

    OpenAIRE

    Liang, J. F.; Signorini, C.

    2005-01-01

    The use of radioactive beams opens a new frontier for fusion studies. The coupling to the continuum can be explored with very loosely bound nuclei. Experiments were performed with beams of nuclei at or near the proton and neutron drip-lines to measure fusion and associated reactions in the vicinity of the Coulomb barrier. In addition, the fusion yield is predicted to be enhanced in reactions involving very neutron-rich unstable nuclei. Experimental measurements were carried ...

  19. Simulation of induced radioactivity for Heavy Ion Medical Machine

    CERN Document Server

    Jun-Kui, Xu; Wu-Yuan, Li; Wang, Mao; Jia-Wen, Xia; Xi-Meng, Chen; Wei-Wei, Yan; Chong, Xu

    2013-01-01

    For radiation protection and environmental impact assessment purpose, the radioactivity induced by carbon ion of Heavy Ion Medical Machine (HIMM) was studied. Radionuclides in accelerator component, cooling water and air at target area which are induced from primary beam and secondary particles are simulated by FLUKA Monte Carlo code. It is found that radioactivity in cooling water and air is not very important at the required beam intensity and energy which is needed for treatment, radionuclides in accelerator component may cause some problem for maintenance work, suitable cooling time is needed after the machine are shut down.

  20. Fusion Induced by Radioactive Ion Beams

    CERN Document Server

    Liang, J F

    2005-01-01

    The use of radioactive beams opens a new frontier for fusion studies. The coupling to the continuum can be explored with very loosely bound nuclei. Experiments were performed with beams of nuclei at or near the proton and neutron drip-lines to measure fusion and associated reactions in the vicinity of the Coulomb barrier. In addition, the fusion yield is predicted to be enhanced in reactions involving very neutron-rich unstable nuclei. Experimental measurements were carried out to investigate if it is feasible to use such beams to produce new heavy elements. The current status of these experimental activities is given in this review.

  1. Avalanches and disorder-induced criticality in artificial spin ices

    International Nuclear Information System (INIS)

    We show that both square and kagome artificial spin ice systems exhibit disorder-induced nonequilibrium phase transitions, with power law avalanche distributions at the critical disorder level. The different nature of geometrical frustration in the two lattices produces distinct types of critical avalanche behavior. For the square ice, the avalanches involve the propagation of locally stable domain walls separating the two polarized ground states, and the scaling collapse agrees with an interface depinning mechanism. In contrast, avalanches in the fully frustrated kagome ice exhibit pronounced branching behaviors that resemble those found in directed percolation. The kagome ice also shows an interesting crossover in the power-law scaling of the avalanches at low disorder. Our results show that artificial spin ices are ideal systems in which to study nonequilibrium critical point phenomena. (paper)

  2. Determination of natural and artificial radioactivity in soil at North Lebanon province

    International Nuclear Information System (INIS)

    The concentrations of natural and artificial radionuclides at 57 sampling locations along the North Province of Lebanon are reported. The samples were collected from uncultivated areas in a region not previously reported. The samples were analyzed by gamma spectrometers with High Purity Germanium detectors of 30% and 40% relative efficiency. The activity concentrations of primordial naturally occurring radionuclides of 238U, 232Th, and 40K varied between 4–73 Bq kg?1, 5–50 Bq kg?1, and 57–554 Bq kg?1 respectively. The surface activity concentrations due to the presence of these radionuclides were calculated and Kriging-geostatistical method was used to plot the obtained data on the Lebanese radioactive map. The results for 238U, 232Th, and 40K ranged from 0.2 kBq m?2 to 9 kBq m?2, from 0.2 kBq m?2 to 3 kBq m?2, and from 3 kBq m?2 to 29 kBq m?2 respectively. For the anthropogenic radionuclides, the activity concentrations of 137Cs founded in soil ranged from 2 Bq kg?1 to 113 Bq kg?1, and the surface activity concentration from 0.1 kBq m?2 to 5 kBq m?2. The total absorbed gamma dose rates in air from natural and artificial radionuclides in these locations were calculated. The minimum value was 6 nGy h?1 and the highest one was 135 nGy h?1 with an average of 55 nGy h?1 in which the natural terrestrial radiation contributes in 99% and the artificial radionuclides mainly 137Cs contributes only in 1%. The total effective dose calculated varied in the range of 7 ?Sv y?1 and 166 ?Sv y?1 while the average value was 69 ?Sv y?1 which is below the permissible limit 1000 ?Sv y?1

  3. The use and production of artificial radioactive isotopes in Hungary over the past 25 years

    International Nuclear Information System (INIS)

    The history of application of artificial radioactive isotopes is reviewed. The first isotope consignement arrived in Hungary in 1954. Between 1954 and 1957 appropriate laboratories were constructed, new techniques developed and specialists were trained. The central coordinating organ, the National Atomic Energy Committee, was founded in 1956. The Institute of Isotopes was established in 1959, the tasks of which include the production and distribution of radioactive preparations, extensive research for new types of radiation sources as well as the development of new methods for activity measurement. Between 1957 and 1970 the development and production of measuring instruments have become especially important. More and more conferences and meetings were organized, basis institutes with specialized programs were founded. The cooperation among the Comecon-countries has become extensive in the 1960-es; in the 1970-es the emphasis has been put on specific tasks. Nowadays more than 1000 different preparations and a total activity of approx. 17000 TBq are produced in a year. (L.E.)

  4. Artificial radioactivity in Cumbria: summary of an assessment by measurement and modelling

    International Nuclear Information System (INIS)

    At the Harwell laboratory, the distributions of the artificial radionuclides discharged by British Nuclear Fuels at Sellafield have been measured within Cumbria, with particular emphasis on the transfer between environmental media. The results of the measurements have been incorporated into a model of the Cumbrian environment. The object of this work is to estimate the radiological impact upon man by exploring the pathways leading to external irradiation, to inhalation and to the ingestion of foodstuffs. Distributions have been established for caesium-137, plutonium isotopes and americium-241. Transfer from sea to land, of actinide radioactivity discharged to the sea, occurs on a very small scale. The relative contributions to deposition and airborne radioactivity from sea-to-land transfer, fallout from nuclear weapons testing and atmospheric releases from Sellafield are compared. The dose resulting from sea-to-land transfer of actinides to a resident of Seascale peaked in 1973 at less than 1% of the ICRP annual limit for the general public and should fall steadily up to the year 2000. (author)

  5. Metal Complexes Containing Natural and and Artificial Radioactive Elements and Their Applications

    Directory of Open Access Journals (Sweden)

    Oxana V. Kharissova

    2014-07-01

    Full Text Available 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 ?-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 (99mTc 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.

  6. Study of the artificial radioactivity of the marine medium using gamma spectrometry (1962-1966)

    International Nuclear Information System (INIS)

    The results described in this study are relative to the artificial radioactivity of such elements as zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 and praseodymium-144 which were present in the atmospheric fallout between 1962 and 1964, and their incidence in superficial marine waters. Various physical, chemical or biological processes are studied by a high sensitivity gamma ray spectrometry technic, using those radioelements as 'tracers'. The change of state in sea water of an important fraction (about 50 per cent) of the radioactive particles going into the soluble phase - this phenomenon was not expected for those radioelements - controls the processes of accumulation in the planktonic biomass and the diffusion towards deeper waters. On the other hand, an 'in situ' spectrometry method is described. It enables the direct measurement in the sea of very low concentrations of some gamma ray emitters. The application of this method has made possible to carry out numerous observations in the surface waters of the Western Mediterranean sea and in the Bay of Biscay. It is shown that the mixing depth is closely connected to the depth of the thermocline. An accumulation process at this level is observed. The diffusion coefficients are similar to the thermal turbulent coefficient. The existence during several months of 'compartments' is established for the surface waters of the Bay of Biscay. From the establishment of the budget of fall-out, a comparative study shows that the rate of radioactive fallout on the maritime zone considered is always two to three times higher than on the neighbouring continental regions. Several explanations of this phenomenon are discussed. (author)

  7. Artificial radionuclides in the ecosystems of the gulfs in the Kola peninsula and in the areas of radioactive wastes keeping

    International Nuclear Information System (INIS)

    The results of radioactive contamination investigations carried out in the Kola Peninsula gulf's ecosystems in the vicinity of the places of radioactive wastes keeping are presented. These investigations were conducted during 1994-2004 by specialists of the Murmansk Marine Biological Institute KSC RAS. The data on the artificial radionuclides contents in bottom sediments, water and hydrobiontes of the Kola, the Motovsky Bays and gulfs of the Barents Sea are presented. Coefficients values of caesium radionuclides distribution between water and bottom sediments of the Kola Bay obtained experimentally and developed on the basis of the data on the composition and amount of artificial radionuclides in bottom sediments classification of bays and gulfs are also given. (author)

  8. Optically induced coherence effects in `artificial atoms and molecules'

    CERN Document Server

    Hohenester, U; Molinari, E; Hohenester, Ulrich; Troiani, Filippo; Molinari, Elisa

    2002-01-01

    Using a master-equation approach for the description of coherent and incoherent dynamics in `artificial atoms and molecules', we present a theoretical analysis of situations where intense laser fields lead to pronounced renormalizations of carrier states. Such enhanced light-matter interactions allow for the solid-state implementation of effects hitherto only observable in atomic systems. Two prototypical examples will be presented: first, we show how two intense laser pulses can be exploited for a robust and high-fidelity population transfer of carrier states in coupled quantum dots; second, we discuss the possibility of observing self-induced transparency in a sample of inhomogenously broadened quantum dots, a phenomenon where intense laser pulses propagate without suffering significant losses.

  9. Preliminary results on artificial radioactivity and elemental content of samples from Black Sea

    International Nuclear Information System (INIS)

    During the international expedition of the research vessel Prof. Vodyanitskiy on the Black Sea, in December 1999, samples of sea water and sediment were collected and analyzed for elemental content and radioactivity. The cruise covered the mouths of the Dniester and Danube River, the Crimean coastal waters and the offshore area. The sediment, collected by an EPA Box corer was separated in layers. Sediment samples were analyzed by gamma spectroscopy for the artificial occurring radionuclide Cs-137. The concentration of some major, minor and trace elements was determined by X-ray fluorescence (XRF) technique. For the water samples, Cs-137 concentration varied between (26.3 ± 3.4) mBq/l and (41.2 ± 5.6) mBq/l for the surface water; a value of (9.9 ± 1.8) mBq/l was found for a deep water sample collected far offshore. The concentration of Sr-90 did not vary significantly from a station to another and was around 11 mBq/l. The concentration of tritium was low (between 24 and 7 T.U.), in the range reported in the recent literature. For all the sampling locations the maximum of the 137 Cs specific activity in sediment samples was found in the surface layer. In the samples collected from the stations 3 and 4, close to the mouths of Danube and Dniester Rivers, higher values up to (128 ± 6) Bq/kg were found. A similar elemental composition of sediment samples in the locations mentioned above was found. Cr and Ni were detected only in the sediment sample collected near the Crimean shore, and are probably correlated to the industrial discharges. (authors)

  10. The induced radioactivity danger parameter for gamma radiation

    International Nuclear Information System (INIS)

    Dosimetric and practical aspects of the induced radioactivity danger parameter, as used for calculating the gamma radiation dose rate near to objects that have been exposed to high energy radiation, are examined. A simplified and more generally applicable method of calculation is proposed, based on energy balance in homogeneous media. The problems of applying this in practice are discussed, and it is shown that corrections are generally small enough to be neglected in many practical applications. Examples of calculations by previous and proposed methods are given. (author)

  11. Radioactive targets for neutron-induced cross section measurements

    International Nuclear Information System (INIS)

    Measurements using radioactive targets are important for the determination of key reaction path ways associated with the synthesis of the elements in nuclear astrophysics (sprocess), advanced fuel cycle initiative (transmutation of radioactive waste), and stockpile stewardship. High precision capture cross-section measurements are needed to interpret observations, predict elemental or isotopical ratios, and unobserved abundances. There are two new detector systems that are presently being commissioned at Los Alamos National Laboratory for very precise measurements of (n,?) and (n,f) cross-sections using small quantities of radioactive samples. DANCE (Detector for Advanced Neutron-Capture Experiments), a 4 ? gamma array made up of 160 BaF2 detectors, is designed to measure neutron capture cross-sections of unstable nuclei in the low-energy range (thermal to ?500 keV). The high granularity and high detection efficiency of DANCE, combined with the high TOF-neutron flux available at the Lujan Center provides a versatile tool for measuring many important cross section data using radioactive and isotopically enriched targets of about 1 milligram. Another powerful instrument is the Lead-slowing down spectrometer (LSDS), which will enable the measurement of neutron-induced fission cross-section of U-235m and other short-lived actinides in a energy range from 1-200 keV with sample sizes down to 10 nanograms. Due to the short half-life of the U-235m isomer (T1/2 = 26 minutes), the samples must be rapidly and repeatedly extracted from its 239Pu parent. Since 239Pu is itself highly fissile, the separation must not only be rapid, but must also be of very high purity (the Pu must be removed from the U with a decontamination factor >1012). Once extracted and purified, the 235mU isomer would be electrodeposited on solar cells as a fission detector and placed within the LSDS for direct (n,f) cross section measurements. The production of radioactive targets of a few milligrams will be described as well as the containment for safe handling of these targets at the Lujan Center at LANSCE. To avoid any contamination, the targets are electrochemically fixed onto thin Ti foils and two foils are placed back to back to contain the radioactive material within. This target sandwich is placed in a cylinder made of aluminum with thin translucent windows made of Kapton. Actinides targets, such as 234,235,236,238U, 237Np, and 239Pu are prepared by electrodeposition or molecular plating techniques. Target thicknesses of 1-2 mg/cm2 with sizes of 1 cm2 or more have been made. Other targets will be fabricated from separation of irradiated isotopically enriched targets, such as 155Eu from 154Sm,171Tm from 170Er, and 147Pm from 146Nd, which has been irradiated in the high flux reactor at ILL, Grenoble. A radioactive sample isotope separator (RSIS) is in the process of being commissioned for the preparation of other radioactive targets. A brief summary of these experiments and the radioactive target preparation technique will be given.

  12. Prediction of radiation induced liver disease using artificial neural networks

    International Nuclear Information System (INIS)

    The objective of this study was to evaluate the efficiency of predicting radiation induced liver disease (RILD) with an artificial neural network (ANN) model. From August 2000 to November 2004, a total of 93 primary liver carcinoma (PLC) patients with single lesion and associated with hepatic cirrhosis of Child-Pugh grade A, were treated with hypofractionated three-dimensional conformal radiotherapy (3DCRT). Eight out of 93 patients were diagnosed RILD. Ninety-three patients were randomly divided into two subsets (training set and verification set). In model A, the ratio of patient numbers was 1:1 for training and verification set, and in model B, the ratio was 2:1. The areas under receiver-operating characteristic (ROC) curves were 0.8897 and 0.8831 for model A and B, respectively. Sensitivity, specificity, accuracy, positive prediction value (PPV) and negative prediction value (NPV) were 0.875 (7/8), 0.882 (75/85), 0.882 (82/93), 0.412 (7/17) and 0.987 (75/76) for model A, and 0.750 (6/8), 0.800 (68/85), 0.796 (74/93), 0.261 (6/23) and 0.971 (68/70) for model B. ANN was proved high accuracy for prediction of RILD. It could be used together with other models and dosimetric parameters to evaluate hepatic irradiation plans. (author)

  13. Medical imaging was boosted by the discovery of artificial radioactivity; L'imagerie medicale revelee par la radioactivite

    Energy Technology Data Exchange (ETDEWEB)

    Demarthon, F.; Dupuy-Maury, F.; Donnars, O

    2002-08-01

    This article draws the history of medical imaging since the discovery of artificial radioactivity in 1934. The author reviews the PET (positron emission tomography) and MRI (magnetic resonance imaging) technologies and presents the recent progress in neuro-sciences that have been made possible by using these 2 technologies. Brain imaging has allowed to show: - the impact of emotions on logical mental processes and on mental performances, - the management of memory in the brain of talented quick reckoners, - the degeneration of neurons, and - the link between autism and the presence of structural and functional anomalies in the brain. (A.C.)

  14. Radiation Sialadenitis Induced by High-dose Radioactive Iodine Therapy

    International Nuclear Information System (INIS)

    Radioactive iodine (131I) is accumulated in the thyroid tissue and plays an important role in the treatment of differentiated papillary and follicular cancers after thyroidectomy. Simultaneously, 131I is concentrated in the salivary glands and secreted into the saliva. Dose-related damage to the salivary parenchyma results from the 131I irradiation. Salivary gland swelling and pain, usually involving the parotid, can be seen. The symptoms may develop immediately after a therapeutic dose of 131I and/or months later and progress in intensity with time. In conjunction with the radiation sialadenitis, secondary complications reported include xerostomia, taste alterations, infection, increases in caries, facial nerve involvement, candidiasis, and neoplasia. Prevention of 131I sialadenitis may involve the use of sialogogic agents to hasten the transit time of the radioactive iodine through the salivary glands. However, studies are not available to delineate the efficacy of this approach. Treatment of the varied complications that may develop encompass numerous approaches and include gland massage, sialogogic agents, duct probing, antibiotics, mouthwashes, good oral hygiene, and adequate hydration. Recently interventional sialoendoscopy has been introduced an effective tool for the management of patients with 131I-induced sialadenitis that is unresponsive to medical treatment.

  15. Radiation Sialadenitis Induced by High-dose Radioactive Iodine Therapy

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Shin Young; Lee, Jaetae [Kyungpook National University Hospital, Daegu (Korea, Republic of)

    2010-06-15

    Radioactive iodine ({sup 131}I) is accumulated in the thyroid tissue and plays an important role in the treatment of differentiated papillary and follicular cancers after thyroidectomy. Simultaneously, {sup 131}I is concentrated in the salivary glands and secreted into the saliva. Dose-related damage to the salivary parenchyma results from the {sup 131}I irradiation. Salivary gland swelling and pain, usually involving the parotid, can be seen. The symptoms may develop immediately after a therapeutic dose of {sup 131}I and/or months later and progress in intensity with time. In conjunction with the radiation sialadenitis, secondary complications reported include xerostomia, taste alterations, infection, increases in caries, facial nerve involvement, candidiasis, and neoplasia. Prevention of {sup 131}I sialadenitis may involve the use of sialogogic agents to hasten the transit time of the radioactive iodine through the salivary glands. However, studies are not available to delineate the efficacy of this approach. Treatment of the varied complications that may develop encompass numerous approaches and include gland massage, sialogogic agents, duct probing, antibiotics, mouthwashes, good oral hygiene, and adequate hydration. Recently interventional sialoendoscopy has been introduced an effective tool for the management of patients with {sup 131}I-induced sialadenitis that is unresponsive to medical treatment.

  16. State of radionuclides in seawater. Comparison of natural stable and artificial radioactive isotope s of mercury and zinc in natural waters of the arid zone of the USSR

    International Nuclear Information System (INIS)

    This paper studies the state of stable and artificial radioactive isotopes of merury and zinc in natural waters of the arid zone of the USSR by radioactivity and radiochemical methods. Convergent results have been obtained for the dissolved forms of mercury and zinc in natural waters of the arid zone in a comparison of the results of radioactivation analysis and laboratory simulation using the radionuclides mercury-203 and zinc-65

  17. Artificial radioactivity in the vicinity of St. Marianna University School of Medicine after the Chernobyl reactor accident

    International Nuclear Information System (INIS)

    Following the Chernobyl reactor accident on April 26, 1986, rain water and atomospheric dust were monitored for their possible contamination by artificial radionuclides on the roof of the building of our medical school from April 30 through June 8, 1986. Radiological monitoring was also performed on cabbages obtained from a nearby field, city water, cow's milk produced in Kanagawa Prefecture and human milk obtained from a volunteer living in Kawasaki. Our campus and the nearby area were exposed to 131I from May 2 through 22 by rainfall and from May 1 through 15 by atomospheric dust. In particular, rain water on May 4 and May 5 contained 7600 pCi (282 Bq)/l and 6000 pCi (222 Bq)/l, respectively. The cabbage specimen obtained on May 7 was contaminated by 131I with 808 pCi/kg wet weight, but another specimen obtained on June 6 was not contaminated by any detectable amounts of 131I. No radioactivity was detected in city water during the period monitored. Cow's milk and human milk contained, as a total of ?-radioactivity, 1412 pCi (52 Bq)/l and 915 pCi (34 Bq)/l, respectively. However, parallel determinations on their potassium concentrations revealed that these radioactivities were due entirely to natural 40K. The degree of radiological contamination in and around our campus following the Chernobyl accident was mostly below the action levels above which the governments of several countries involving Japan would take preventive measures against possible radiation damages. Although 131I radioactivities contained in the rain water of the first week of May, 1986 significantly exceeded the action level for this radionuclide, their effects on human health were considered negligible and undetectable in the vicinity of our school. (author)

  18. The electrical charging of inactive aerosols in high ionised atmosphere, the electrical charging of artificial beta radioactive aerosols

    International Nuclear Information System (INIS)

    The electrical properties of aerosols greatly influence their transport and deposition in a containment. In a bipolar ionic atmosphere, a neutral electric charge on aerosols is commonly assumed. However, many studies report a different charge distribution in some situations, like highly ionised atmosphere or in the case of radioactive aerosols. Such situations could arise from a hypothetical accident in a nuclear power plant. Within the framework of safety studies which are carried out at IPSN, our aims were the study of electrical properties of aerosols in highly ionised atmosphere, and the study of artificial radioactive aerosols, in order to suggest experimental validation of available theories. For this purpose, we designed an experimental device that allows us to measure non-radioactive aerosol charge distribution under high gamma irradiation, up to 104 Gy/h. With our experimental device we also studied the properties of small ions in the medium. Our results show a variation of the charge distribution in highly ionised atmosphere. The charge increases with the dose of gamma ray. We have related this variation with the one of the small ions in the gases, according to theoretical prediction. However, the model overestimates slightly our experimental results. In the case of the radioactive aerosols, we have designed an original experimental device, which allows us to study the charge distribution of a 137Cs aerosol. Our results show that the electric charging of such aerosols is strongly dependent on evolution parameters in a containment. So, our results underline a great enhancement of self-charging of particles which are sampled in a confined medium. Our results are qualitatively in agreement with the theoretical model; nevertheless the latter underestimates appreciably the self-charging, owing to the fact that wall effects are not taken into account. (author)

  19. Study of the behaviour of artificial radioactive aerosols. Applications to some problems of atmospheric circulation (1963)

    International Nuclear Information System (INIS)

    The aim of this work, consists in the examination of the behaviour of radioactive aerosols produced in the atmosphere by nuclear explosions, in order to deduce the most general laws governing atmospheric circulation and diffusion. After having given a general table of the radioactive aerosols present the authors consider the validity and the precision of the measurement methods and the concentration of the aerosols at ground level and in the upper atmosphere, as well as their deposition on the ground. The existence is thus demonstrated of a tropospheric equatorial barrier and of discontinuous and seasonal aspects of stratosphere-troposphere transfers. The role is shown of precipitations and dry auto-filtration in the lower atmosphere cleaning processes. This work makes it possible to describe the general behaviour of dust from the stratosphere, and to improve the total radioactive contamination of the globe. (author)

  20. Effective dose equivalent to breast fed infants due to artificial and natural radioactivity

    International Nuclear Information System (INIS)

    After the Chernobyl accident, the Italian National Institute of Health (ISS), with the collaboration of the Epidemiological Unit of Latium District, started a research devoted to the study of the radioactive contamination of human milk in Latium. The motivation is three-fold, namely: to measure the contamination of a food product utilised for infants in order to assess the corresponding dose to breast-fed infants; to clarify any possible correlations between radioactive levels in human milk and those in the total body; to correlate the levels in human milk with those in the maternal diet

  1. Designing a program to assess potential induced radioactivity in electron beam sterilization of medical devices

    International Nuclear Information System (INIS)

    ISO 11137-1:2006 requires that the potential for induced radioactivity be evaluated for medical devices irradiated with electrons with energy more than 10 MeV. For a manufacturing operation where new devices are being developed, a practical program for making such an evaluation needs to be engrained in the process. A program was developed such that the induced radioactivity evaluation is imbedded in the development of the irradiation process. - Highlights: • A program is described to evaluate induced radioactivity in electron beam. • The program entails evaluation of design prior to manufacturing. • Radiation measurement is done immediately following irradiation. • The instrument has adequate sensitivity for this purpose

  2. Artificial Intelligence based Solver for Governing Model of Radioactivity Cooling, Self-gravitating Clouds and Clusters of Galaxies

    Directory of Open Access Journals (Sweden)

    Junaid Ali Khan

    2013-06-01

    Full Text Available In this study, a reliable alternate platform is developed based on artificial neural network optimized with soft computing technique for a non-linear singular system that can model complex physical phenomenas of the nature like radioactivity cooling, self-gravitating clouds and clusters of galaxies. The trial solution is mathematically represented by feed-forward neural network. A cost function is defined in an unsupervised manner that is optimized by a probabilistic meta-heuristic global search technique based on annealing in metallurgy. The results of the designed scheme are evaluated by comparing with the desired response of the system. The applicability, stability and reliability of the proposed method is validated by Monte Carlo simulations.

  3. Measurement of natural radioactivity and radiation hazards for some natural and artificial building materials available in Romania

    International Nuclear Information System (INIS)

    As building materials are known to be the second source regarding high radon concentrations, it is very important to determine the amounts of natural radionuclides from every building material in use. In the present study the most frequently used Romanian natural (sand, gypsum, limestone) and artificial (portland cement, lime, clinker, electrofilter powder, fly ash, cement-lime plaster mortar, cement plaster mortar) building materials were analyzed. The absorbed dose rate and the annual effective dose equivalent rate for people living in dwelling buildings made of these building materials under investigation were also calculated. The analysis was performed with gamma-ray spectrometry, with two hyper-pure germanium detectors. The activity concentrations of natural radionuclides were in the ranges: 5.2-511.8 Bq kg-21 for 226Ra; 0.6-92.6 Bq kg-1 for 232Th and -1 for 40K, respectively. The radium equivalent activity in the fifty-one (51) samples varied from 9 to 603 Bq kg-1. By calculating all the radioactivity indices (Raeq, Hext, I?, Iyr) it was found that all the building materials under investigation can be used to erect dwelling buildings. Except for sample SA6, SA7 and SA11 among the natural building materials and sample SG1, SG2, FAH1, CLM1, CM1 among the artificial building materials that are considered hazardous materials when are used in large quantities. (author)

  4. Artificial radioactivity layers in the Devon Island ice cap, Northwest Territories

    International Nuclear Information System (INIS)

    Bomb-produced radioactive fall-out layers are evident in the firn at the top of the Devon Island ice cap and also lower down in a zone where accumulation is in the form of re-frozen melt-water. This allows 1963-1974 snow accumulation (positive balance) gradients for the same period to be determined on sub-polar ice caps in Canada. (author)

  5. NATURAL AND ARTIFICIAL RADIOACTIVITY IN BULGARIAN SOILS ALONG THE DANUBE RIVER

    Directory of Open Access Journals (Sweden)

    I YORDANOVA

    2005-07-01

    Full Text Available Data from gamma-spectrometry analyses of soils and sediments samples taken along the Danube river is presented in the paper. Results about the content of natural and artifi cial radionuclides like Sr-90 and Cs-137 are discussed. The region around the Kozloduj NPP including its exclusion zone is investigated in more details. Data from the last years is compared with such from former investigations of similar samples from the region. The soil is a natural depot and initial reservoir for spreading of all man-made radionuclides and natural radioactivity. The man-made isotopes with the longest half-life time, like Sr-90 and Cs-137 are mainly investigated. Because of their feature to be bioelements, that is to include themselves in human’s metabolism, they are especially dangerous when their concentrations in the nutritious chain increase. That is why the investigation of these nuclides together with the natural once like uranium, thorium and radium started in 1978 with annual determination of their concentrations in soils collected from the region of “Kozloduj” NPP and some places along the Danube river potentially exposed to radioactive contamination. The aim was to make a picture of the radioecological status of the soils along the Danube river. The period after 1986 is concerned as the accident in Chernobyl’s NPP changed basically the radioactive situation in the country.

  6. Human Health Impact of Natural and Artificial Radioactivity Levels in the Sediments and Fish of Bonny Estuary, Niger Delta, Nigeria

    Directory of Open Access Journals (Sweden)

    Bolaji B. Babatunde

    2015-11-01

    Full Text Available There is widespread contamination of the environment of the Niger Delta, which may include enhanced background levels of naturally occurring radioactive materials (NORM due to oil production and rapid urbanization activities. Sediments and seafood from the Bonny estuary, Niger Delta, were collected for the purpose of determining baseline data on artificial and natural radioactivity and estimation of effective doses for the public due to ingestion of seafood from the study area. The highest and lowest activity concentrations were reported for 40K and 137Cs in both sediments and fish samples of the Bonny estuary. There was some evidence of spatial variability in the 40K and 137Cs data, with the latter being the likely result of dredging. Other radionuclides were not significantly different between sites impacted by industrial activities or not. Activity of radionuclides measured in the sediments of the study area were higher than reported elsewhere in the Niger Delta and Nigeria and higher than reported global averages by UNSCEAR. The total highest activity concentration in all fish species of gamma emitting radionuclides was observed for 40K, followed by 238U, 232Th and 226Ra, respectively, while 137Cs had the lowest activity concentration. However, 210Po activities were the most important in terms of dose contribution. Consumption of molluscs at typical rates could result in doses exceeding 1 mSv·y?1. Although this baseline data may not be conclusive on prevailing trends in radioactivity in the study area, higher consumption rates of the species studied may have public health consequences due to effects of low dose ionising radiation.

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

    International Nuclear Information System (INIS)

    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 137Cs 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

  8. Exchange of Radioactive Phosphorus 32P between the Components of an Artificial Plant Community

    Directory of Open Access Journals (Sweden)

    K. Zarzycki

    2015-05-01

    Full Text Available In artificial plant communities (wooden cases with soil the following plants were grown together for one year: case No. 1: Betula verrucosa Ehrh. (2 specimens and Carex pilosa Scop.; sases No. 2 and 3: Alnus incana (L. Mnch., Fraxinus excelsior L., Podus avium Mili., Aegopodiurti podagraria L., Eupatorium cannabinum L. and others. Into the stalks or stems of one to three plants of every case 32P was introduced. After 3 months all the plants in every case contained radiactive phosphorus. There were great differences in 32P concentration (up to ten-fold between plants grown in the same case. The concentration of 32P in plants into which it had not been introduced was of the range of 0.1%.

  9. Exchange of radioactive phosphorus 32P between the components of an artificial plant community

    International Nuclear Information System (INIS)

    In artificial plant communities (wooden cases with soil) the following plants were grown together for one year: case No. 1: Betula verrucosa Ehrh. (2 specimens) and Carex pilosa Scop.; cases No. 2 and 3: Alnus incana (L.) Mnch., Fraxinus excelsior L., Padus avium Mill., Aegopodium podagraria L., Eupatorium cannabinum L. and others. Into the stalks or stems of one to three plants of every case 32P was introduced. After 3 months all the plants in every case contained radiactive phosphorus. There were great differences in 32P concentration (up to ten-fold) between plants grown in the same case. The concentration of 32P in plants into which it had not been introduced was of the range of 0.1%. (author)

  10. Evaluation of artificial radioactivity of the North Western Mediterranean Sea and evaluation of the sanitary consequences

    Energy Technology Data Exchange (ETDEWEB)

    Calmet, D.; Daburon, M.L.; Willemot, J.M. (Commissariat a l' Energie Atomique, Institut de Protection et de Surete Nucleaire, 92 - Fontenay-aux-Roses (France))

    1985-01-01

    The results of radiological measurements of the North Western Mediterranean observation network outline the level of artificial radionuclides coming from industrial seewages, WRu and from atmospheric fall out, TXCs and sup(239 + 240)Pu measured on 3 differents types of bioindicators: Mytilus sp., Posidonia oceanica (L.) Del. and demersal fishes as Solea sp., Anguilla anguilla L., Conger conger L. Mytilus sp. is quite a perfect bioindicator of radionuclides contamination but must be linked with fishes sampling which muscles concentrate Cesium at higher level. The sanitary consequences for the waterside population involved by molluscs and fishes ingestion contamined by these 3 radionuclides lead to a fraction (10 V) of the annual dose limit recommanded by the ICRP 26.

  11. Evaluation of artificial radioactivity of the north Western mediterranean sea and evaluation of the sanitary consequences

    International Nuclear Information System (INIS)

    The results of radiological measurements of the north west mediterranean observation network outline the level of artificial radionuclides coming from industrial seewages, 106Ru and from atmospheric fall out, 137Cs and sup(239+240)Pu measured on 3 differents types of bioindicators: Mytilus sp., Posidonia oceanica (L.) Del. and demersal fishes as Solea sp., Anguilla anguilla L., Conger conger L. Mytilus sp. is quite a perfect bioindicator of radionuclides contamination but must be linked with fishes sampling which muscles concentrate Cesium at higher level. The sanitary consequences for the waterside population involved by molluscs and fishes ingestion contamined by these 3 radionuclides lead to a fraction (10-5) of the annual dose limit recommanded by the ICRP 26

  12. Study on natural and artificial radioactivity of sea water, algae, fish, sea organisms and bottom sediments for the period 1965-1974

    International Nuclear Information System (INIS)

    Studies on natural and artificial radioactivity of some fish species, algae, mussels, etc., inhibiting Varna seacoast were carried out in 1965-1974. The samples were radiochemically investigated for total ?-activity, contents of potassium 40, uranium natural, radium 226, strontium 90, and cesium 137. A total of 602 samples are investigated. The results obtained from studying sea water show highest concentration in the village Byala - up to 69,00.10-9 Ci/l, and lowest - in the village of Shabla - up to 32,00.10-9 Ci/l. Radioactivity of some fish varies from 7,10 up to 67,50 pCi (per kg fresh product for strontium 90), and from 14,3 up to 63,50 pCi (per kg fresh product for cesium 137). It is established that scad fish contains the highest radioactivity. Data show that radioactivity in all cases was within the maximum permissible activity level. (author)

  13. Natural and artificial radioactivity in milk and dairy products for human consumption (1971-2003)

    International Nuclear Information System (INIS)

    Between 1971 and 2003, radioactivity analyses were performed in several dairy products (fresh milk, milk in powder, evaporated milk and in mixed-cereal flours) as part of the program of national environmental radiological surveillance developed by the Department of Environment Control of the Peruvian Nuclear Energy Institute. Analytical assays were performed to evaluate Cs-137, Cs-134, I-131, K-40, Sr-90 (by gamma spectroscopy) and gross beta activity (by beta counting). The obtained values do not represent radiosanitary risk for the population and confirm the presence of K-40 as the main radionuclide in this type of samples. The application of IAEA dosimetric factors allowed calculating intake doses from dairy products in a much lower level than the limits established by international regulation bodies. (author)

  14. Use of artificial barriers in a site for surface storage of radioactive waste

    International Nuclear Information System (INIS)

    The objective is the on site study of the influence of an injection screen on the flow in a water table of a porous medium, in order to improve the safety of a surface radioactive waste storage site. A hydrodispersive study has provided information for the definition of the role of the screen: the transfer times of the pollutant in the water table are increased by a factor of 2 and, in comparison, the concentration are clearly reduced by a factor of 10. The implantation of an injection screen in the ground should result in an improvement in the restrictive quality of the barrier and the contamination of an aquifer should be slower without interruption to the flow

  15. Radioactivity of Tobacco Leaves and Radiation Dose Induced from Smoking

    Directory of Open Access Journals (Sweden)

    Constantin Papastefanou

    2009-02-01

    Full Text Available The radioactivity in tobacco leaves collected from 15 different regions of Greece and before cigarette production was studied in order to find out any association between the root uptake of radionuclides from soil ground by the tobacco plants and the effective dose induced to smokers from cigarette tobacco due to the naturally occurring primordial radionuclides , such as 226Ra and 210Pb of the uranium series and 228Ra of the thorium series and/or man-made radionuclides, such as 137Cs of Chernobyl origin. Gamma-ray spectrometry was applied using Ge planar and coaxial type detectors of high resolution and high efficiency. It was concluded that the activities of the radioisotopes of radium, 226Ra and 228Ra in the tobacco leaves reflected their origin from the soil by root uptake rather than fertilizers used in the cultivation of tobacco plants. Lead-210 originated from the air and was deposited onto the tobacco leaves and trapped by the trichomes. Potassium-40 in the tobacco leaves was due to root uptake either from soil or from fertilizer. The cesium radioisotopes 137Cs and 134Cs in tobacco leaves were due to root uptake and not due to deposition onto the leaf foliage as they still remained in soil four years after the Chernobyl reactor accident, but were absent from the atmosphere because of the rain washout (precipitation and gravitational settling. The annual effective dose due to inhalation for adults (smokers for 226Ra varied from 42.5 to 178.6 ?Sv/y (average 79.7 ?Sv/y, while for 228Ra from 19.3 to 116.0 ?Sv/y (average 67.1 ?Sv/y and for 210Pb from 47.0 to 134.9 ?Sv/y (average 104.7 ?Sv/y, that is the same order of magnitude for each radionuclide. The sum of the effective doses of the three radionuclides varied from 151.9 to 401.3 ?Sv/y (average 251.5 ?Sv/y. The annual effective dose from 137Cs of Chernobyl origin was three orders of magnitude lower as it varied from 70.4 to 410.4 nSv/y (average 199.3 nSv/y.

  16. Radioactivity

    International Nuclear Information System (INIS)

    Large amounts of radioactivity can be released in nuclear accidents and nuclear explosions. Important events since the atomic bombs of 1945 are listed more or less in chronological order, including the nuclear weapons tests after World War II and the accidents recorded in nuclear facilities. (DG)

  17. Comparative experimental analysis of the effect caused by artificial and real induced damage in composite laminates

    OpenAIRE

    Pérez Martínez, Marco Antonio; Gil Espert, Lluís; Sánchez Romero, Montserrat; Oller Martínez, Sergio Horacio

    2014-01-01

    This paper presents the results of an extensive experimental campaign aimed to examine the effect upon the vibration response and on the residual load-bearing capacity caused by both: isolated artificially induced interlaminar damage and low-velocity impact induced damage in composite laminates. The experimental programme included modal testing, drop-weight impact testing, ultrasonic inspection, transverse quasi-static loading testing and compression testing conducted on a set of 72 carbon fi...

  18. Destabilization of artificial biomembrane induced by the penetration of tryptophan

    Energy Technology Data Exchange (ETDEWEB)

    Chen Liuhua [Department of Chemistry, Tongji University, Shanghai 200092 (China); Gan Lihua, E-mail: ganlh@tongji.edu.cn [Department of Chemistry, Tongji University, Shanghai 200092 (China); Liu Mingxian; Fan Rong; Xu Zijie; Hao Zhixian; Chen Longwu [Department of Chemistry, Tongji University, Shanghai 200092 (China)

    2011-03-15

    The effect of tryptophan on the membrane stability was studied by using three artificial biological membranes including liposome, Langmuir monolayer and solid supported bilayer lipid membrane (s-BLM) as models. All the results indicate that the penetration of tryptophan can destabilize different artificial biological membranes. The diameter of liposome and the leakage of calcein from liposome increased with the increase of tryptophan concentration because the penetration of tryptophan was beneficial for dehydrating the polar head groups of lipids and the formation of fusion intermediates. {pi}-A isotherms of lecithin on the subphase of tryptophan solution further confirm that tryptophan can penetrate into lipid monolayer and reduce the stability of lipid monolayer. When the concentration of tryptophan increased from 0 to 2 x 10{sup -3} mol L{sup -1}, the limiting molecular area of lecithin increased from 110.5 to 138.5 A{sup 2}, but the collapse pressure of the monolayer decreased from 47.6 to 42.3 mN m{sup -1}, indicating the destabilization of lipid monolayer caused by the penetration of tryptophan. The resistance spectra of s-BLM demonstrate that the existence of tryptophan leads to the formation of some defects in s-BLM and the destabilization of s-BLM. The values of electron-transfer resistance and double layer capacitance respectively decreased from 5.765 x 10{sup 6} {Omega} and 3.573 x 10{sup -8} F to 1.391 x 10{sup 6} {Omega} and 3.340 x 10{sup -8} F when the concentration of tryptophan increased from 0 to 2 x 10{sup -3} mol L{sup -1}. Correspondingly, the breakdown voltage of s-BLM decreased from 2.51 to 1.72 V.

  19. Destabilization of artificial biomembrane induced by the penetration of tryptophan

    International Nuclear Information System (INIS)

    The effect of tryptophan on the membrane stability was studied by using three artificial biological membranes including liposome, Langmuir monolayer and solid supported bilayer lipid membrane (s-BLM) as models. All the results indicate that the penetration of tryptophan can destabilize different artificial biological membranes. The diameter of liposome and the leakage of calcein from liposome increased with the increase of tryptophan concentration because the penetration of tryptophan was beneficial for dehydrating the polar head groups of lipids and the formation of fusion intermediates. ?-A isotherms of lecithin on the subphase of tryptophan solution further confirm that tryptophan can penetrate into lipid monolayer and reduce the stability of lipid monolayer. When the concentration of tryptophan increased from 0 to 2 x 10-3 mol L-1, the limiting molecular area of lecithin increased from 110.5 to 138.5 A2, but the collapse pressure of the monolayer decreased from 47.6 to 42.3 mN m-1, indicating the destabilization of lipid monolayer caused by the penetration of tryptophan. The resistance spectra of s-BLM demonstrate that the existence of tryptophan leads to the formation of some defects in s-BLM and the destabilization of s-BLM. The values of electron-transfer resistance and double layer capacitance respectively decreased from 5.765 x 106 ? and 3.573 x 10-8 F to 1.391 x 106 ? and 3.340 x 10-8 F when the concentration of tryptophan increased from 0 to 2 x 10-3 mol L-1. Correspondingly, the breakdown voltage of s-BLM decreased from 2.51 to 1.72 V.

  20. Evaluation of induced radioactivity in 10 MeV electron-irradiated spices

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu; Ito, Norio; Mizohata, Akira; Matsunami, Tadao; Katayama, Tadashi; Toratani, Hirokazu (Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology); Takeda, Atsuhiko

    1993-10-01

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

  1. Application of naturally occurring isotopes and artificial radioactive tracer for monitoring water flooding in oil field

    International Nuclear Information System (INIS)

    Water flooding is an important operation to enhance oil recovery. Water is injected in the oil formation under high pressure through an injection well. Movement of the injected water is needed to be traced to test the performance of water flood, investigate unexpected anomalies in flow and verify suspected geological barriers or flow channels, etc. In the present study environmental isotopes and artificial radiotracer (tritium) were used at Fimkassar Oil Field of Oil and Gas Development Company Limited (OGDCL) where water flooding was started in March 1996 in Sakessar formation to maintain its pressure and enhance the oil recovery. Environmental isotopes: /sup 18/O, /sup 2/H and /sup 3/H, and chloride contents were used to determine the breakthrough/transit time and contribution of fresh injected water. Water samples were collected from the injection well, production well and some other fields for reference indices of Sakessar Formation during June 1998 to August 1999. These samples were analyzed for the /sup 18/O, /sup 2/H and /sup 3/H, and chloride contents. Results show that the water of production well is mixture of fresh water and formation water. The fresh water contribution varied from 67% to 80%, while remaining component was the old recharged formation water. This percentage did not change significantly from the time of break-through till the last sampling which indicates good mixing in the reservoir and absence of any quick channel. The initial breakthrough time was 27 months as the fresh water contributed significantly in the first appearance of water in the production well in June 1998. Tritium tracer, which was injected in November 1998, appeared in the production well after 8 months. It show that breakthrough time decreased with the passage of time. /sup 14/C of inorganic carbon in the water in Chorgali and Sakessar Formations was also analyzed which indicates that the water is at least few thousand years old. (author)

  2. The possibilities and limits of monitoring of artificial radioactivity of seawater by measuring the gross radiation at permanent measuring stations at sea

    International Nuclear Information System (INIS)

    A radiological measuring network is operated in the Heligoland Bay and the western Baltic. The monitoring equipment is installed on lightships and on Heligoland. Radon decomposition products are found to a depth of 15 m in the water. The artificial radioactivity in the range of 0.1-10 p Ci/l found in the sea is monitored by flux counters as it varies with time. (DG)

  3. Radioactive contamination of the Shagan river ecosystem components with artificial radionuclides

    International Nuclear Information System (INIS)

    Full text: The Shagan river is the only surface waterway on the Semipalatinsk Nuclear Test Site territory. It flows along the eastern boundary of the SNTS and is a left-bank tributary of the Irtysh river. The length of the Shagan riverbed is 275 km with an average slope 0.003, which changes considerably from one part of the riverbed to the other. Within the Balapan testing ground the length of the riverbed is about 50 km, and the slope angle is, on average, 0.002. The watershed area of the left-bank part of the testing ground, where testing wells are located, is about 900 km2. In 2006 during radio-ecological investigations of the SNTS aquatic environment, scientists determined contamination of the Shagan river with radioactive products of nuclear explosions. The main radioactive pollutant is tritium. Maximal tritium concentration in the river waters (40*104 Bq/l) was registered 4.7 km away from the Atomic lake at levels of more than 50 times higher than the maximal permissible level for drinking water. As the distance from the Atomic lake increases, tritium concentration in the Shagan waters considerably decreases, and in the place of its confluence with the Irtysh rivertritium concentration in water becomes 10 Bq/l, which is equal to MPL (maximal permissible level) used for equipment. A complex of scientific investigations including hydrogeological, hydrological and geophysical investigation showed that tritium contamination of the Shagan waters is caused by the discharge of contaminated ground waters from the testing ground Balapan. In 2007 additional investigations of the river ecosystem showed that surface waters of the river in addition to tritium contained 90Sr, and bottom sedimentations were contaminated with 60Co, 152Eu, 154Eu and 137Cs. It should be noted that concentration of 90Sr in water reaches the level comparable with intervention level established by NRB-99 (Radiation Safety Norms) for water and food intake. By the character of tritium and 90Sr distribution in water, it was established that the radionuclides have absolutely different sources. Whereas the nature of tritium presence in the water is quite understandable, the source of 90Sr has not been studied yet. To determine the reasons for noticeable increase of the 90Sr concentration in water and the ways of its proliferation into the river, additional investigations are necessary. Possible mechanisms for 90Sr proliferation into the river may be its inflow with ground waters, plane washing off, washing out of 90Sr from contaminated man-made soils of Atomic Lake by atmospheric precipitations. The present-day situation is complicated by active development of pasture cattle breeding and stocking of fodder crops within the bank zone of the shagan river. High tritium concentration, up to 24000 Bq/l, was also registered in the vegetation of the river-bank zone. The presence of tritium was detected in animal products produced by farms situated on the banks of the Shagan river. Tritium concentration in milk samples reaches 5.0*103 Bq/l, which does not exceed maximal permissible values but requires thorough investigation of the problem as tritium concentration in the Shagan waters may vary in a wide range

  4. Inhibition of artificially induced cough in man by bronchodilators.

    OpenAIRE

    Lowry, R.; Higenbottam, T.; T. Johnson; Godden, D.

    1987-01-01

    1. The antitussive properties of bronchodilators were evaluated in a total of 47 normal volunteers. 2. Cough was induced by inhalation of ultrasonically nebulized solutions of distilled water and hypotonic saline. 3. Inhaled fenoterol hydrobromide (360 micrograms; 20 volunteers) and inhaled ipratropium bromide (72 micrograms; 14 volunteers) both significantly reduced couch compared with placebo (P less than 0.01). Oral salbutamol sulphate (4 mg; 11 volunteers) and oral pirenzepine hydrochlori...

  5. In vitro comparison of laser induced lithotripsy on artificial stones by means of different laser systems

    Science.gov (United States)

    Sroka, R.; Hecht, V.; Reich, O.; Seitz, M.; Stief, C. G.; Bader, M. J.

    2009-02-01

    Objectives: In this study, clinically available pulsed laser systems emitting either in the infrared (IR) - or visible (VIS) spectral region were compared in a standardized manner with respect to their impact on phantom stones in an underwater laboratory set-up. Methods: There were three pulsed laser systems emitting light either in the IR (?=2100nm: Ho: YAG-laser) or VIS (?=532nm/1064nm: FREDDY-laser and 598nm: FLPD-laser) spectral range available for this investigation. After determination of the ablation threshold different fragmentation rates were determined in relation to the fluence (depending on pulse energy and fiber diameter) using artificial stones. Results: The threshold value of the laser pulse energy to induce an ablation of artificial stones induced by the different laser systems showed that even the lowest laser settings induced significant ablation with no regards to the repetition rate and fiber diameter. The VIS-lasers showed higher fragmentation rates than the IR-lasers. Conclusions: VIS-lasers are solely useful for laser induced shockwave lithotripsy, while IR-lasers are also in use for other clinical applications (e.g. coagulation and ablation). Investigations on artificial stone fragmentation are useful to compare clinical laser parameter settings but can partially be transferred to clinically urinary stone fragmentation.

  6. Studies of muon-induced radioactivity at NuMI

    Energy Technology Data Exchange (ETDEWEB)

    Boehnlein, David j.; Leveling, A.F.; Mokhov, N.V.; Vaziri, K.; /Fermilab; Iwamoto, Y.; Kasugai, Y.; Matsuda, N.; Nakashima, H.; Sakamoto, Y.; /JAEA, Ibaraki; 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.

  7. Observation of the effects of artificially released long half-life radionuclides on the global radioactive contamination background in the Atlantic and its adjoining seas

    International Nuclear Information System (INIS)

    In the behaviors of artificial and natural radionuclides in ocean, there is similarity. In the surface seawater in northern Atlantic Ocean, the seasonal variation in the concentration of falling strontium-90 was established, and its empirical formula was given. The review of the measured results of strontium-90, cesium-137 and -134 in North Sea and the former two in southern Baltic Sea indicated that the radioactive contamination in North Sea due to the release of the radioactive materials, which are not regulated in London Convention concerning the sea dumping of wastes, is far higher than the peak in 1963. Also by the exchange of water masses, radioactive materials entered Baltic Sea. The inflow of cesium-137 from North Sea into Baltic Sea in 1979 was over 10 times as much as that from rivers. In the sea area adjoining the strait, however, cesium-137 of high concentration was not observed. (J.P.N.)

  8. Artificial sweeteners produce the counterintuitive effect of inducing metabolic derangements.

    Science.gov (United States)

    Swithers, Susan E

    2013-09-01

    The negative impact of consuming sugar-sweetened beverages on weight and other health outcomes has been increasingly recognized; therefore, many people have turned to high-intensity sweeteners like aspartame, sucralose, and saccharin as a way to reduce the risk of these consequences. However, accumulating evidence suggests that frequent consumers of these sugar substitutes may also be at increased risk of excessive weight gain, metabolic syndrome, type 2 diabetes, and cardiovascular disease. This paper discusses these findings and considers the hypothesis that consuming sweet-tasting but noncaloric or reduced-calorie food and beverages interferes with learned responses that normally contribute to glucose and energy homeostasis. Because of this interference, frequent consumption of high-intensity sweeteners may have the counterintuitive effect of inducing metabolic derangements. PMID:23850261

  9. Evaluation of induced radioactivity in 10 MeV-electron irradiated spices, (1); [gamma]-ray measurement

    Energy Technology Data Exchange (ETDEWEB)

    Furuta, Masakazu; Katayama, Tadashi; Ito, Norio; Mizohata, Akira; Matsunami, Tadao; Shibata, Setsuko; Toratani, Hirokazu (Osaka Prefectural Univ., Sakai (Japan). Research Inst. for Advanced Science and Technology); Takeda, Atsuhiko

    1994-02-01

    Black pepper, white pepper, red pepper, ginger and turmeric were irradiated with 10 MeV electrons from a linear accelerator to a dose of 100 kGy and radioactivity was measured in order to estimate induced radioactivity in the irradiated foods. Induced radioactivity could not be detected significantly by [gamma]-ray spectrometry in the irradiated samples except for spiked samples which contain some photonuclear target nuclides in the list of photonuclear reactions which could produce radioactivity below 10 MeV. From the amount of observed radioactivities of short-lived photonuclear products in the spiked samples and calculation of H[sub 50] according to ICRP Publication 30, it was concluded that the induced radioactivity and its biological effects in the 10 MeV electron-irradiated natural samples were negligible in comparison with natural radioactivity from [sup 40]K contained in the samples. (author).

  10. Artificial Vaginocervical Stimulation Induces a Conditioned Place Preference in Female Rats

    OpenAIRE

    Meerts, Sarah H.; Clark, Ann S.

    2008-01-01

    Female rats express a conditioned place preference (CPP) for a context paired with mating. During a mating encounter, the female rat is exposed to several different types of stimuli, including, but not limited to, vaginocervical stimulation and social contact. The present experiment tested the hypothesis that two components of the mating interaction, vaginocervical stimulation or social contact, each induce a CPP in female rats. During conditioning rats received nonpaced mating, artificial va...

  11. A decade of assessment of the natural and artificial radioactivity in feedstuff and food commodities imported and exported by Brazil

    International Nuclear Information System (INIS)

    Full text: Natural and artificial radionuclides in feedstuff with concentration levels surpassing the brazilian (CNEN-NN 3.05, January 2005) and international (IAEA 115 Safety Series, 1996 and Codex Alimentarius, 2006) limits are harmless to the human health and an effective control is needed in order to only allow consumption of products presenting radiation levels below limits. Since 1988, after the Chernobyl accident, the Environmental Radiometric Laboratory at the Nuclear and Energy Research Institute, IPEN-CNEN/SP (Instituto de Pesquisas Energeticas e Nucleares), performs, on a regular basis, analysis of potassium-40, cesium-134 and cesium-137 concentrations in feedstuff and food commodities imported and exported by Brazil. The present work covers mostly a decade of results, from 1996 to 2007, assessed from the measurements of almost 2600 samples. The imported Belgium and the exported ones are originated from 14 Brazilian States and 111 regions. Nearly 90 different kinds of feedstuff and food commodities were measured, including condensed milk, milk powder, soy beans, sugar, raw coffee beans, etc. All samples were analyzed by high resolution gamma-spectrometry and the results, compared with brazilian and international limits, released as a technical report. The radioactivity present in all analyzed products was within the international limits, allowing to conclude that consumption of such goods offers no health risk derived from radiation. Potential relationships between the type and the origin of the products exported and imported by Brazil and the radionuclides concentrations are also approached. Finally, all results will contribute to the establishment of a radiometric database for the radionuclides concentrations in the feedstuff and food commodities produced in Brazil. (author)

  12. Fusion probability for neutron-rich radioactive Sn induced reactions

    Energy Technology Data Exchange (ETDEWEB)

    Liang, J Felix [ORNL; Gross, Carl J [ORNL; Kohley, Zachary W [ORNL; Shapira, Dan [ORNL; Varner Jr, Robert L [ORNL; Allmond, James M [ORNL; Caraley, Anne L [State University of New York, Oswego; Lagergren, Karin B [ORNL; Mueller, Paul Edward [ORNL

    2012-01-01

    Evaporation residue cross sections for $^{124,126,127,128}$Sn+$^{64}$Ni and $^{132}$Sn+$^{58}$Ni have been measured to study the effects of neutron excess in neutron-rich radioactive nuclei on fusion. For the reactions with $^{64}$Ni, the fusion probability does not decrease with increasing neutron excess in Sn, contrary to the result of the stable beam Sn+Zr measurement. A comparison of the reduced evaporation residue cross sections for $^{126}$Sn+$^{64}$Ni and $^{132}$Sn+$^{58}$Ni, which make the same compound nucleus, shows that the fusion probability is indistinguishable for reactions involving the same atomic elements but different isotope combinations.

  13. Induced radioactivity in a 4 MW target and its surroundings

    CERN Document Server

    Agosteo, Stefano; Otto, Thomas; Silari, Marco

    2003-01-01

    An important aspect of a future CERN Neutrino Factory is the material activation arising from a 2.2 GeV, 4 MW proton beam striking a mercury target. An estimation of the hadronic inelastic interactions and the production of residual nuclei in the target, the magnetic horn, the decay tunnel, the surrounding rock and a downstream dump was performed by the Monte Carlo hadronic cascade code FLUKA. The aim was both to assess the dose equivalent rate to be expected during maintenance work and to evaluate the amount of residual radioactivity, which will have to be disposed of after the facility has ceased operation.

  14. A history of study on safety of irradiated foods (3). Induced radioactivity in irradiated foods

    International Nuclear Information System (INIS)

    Food irradiation can induce a small amount of radioactivity in the foods. The principal mechanisms of the nuclear reactions are (n, ?), (?, n), (?, ?'). The resulting nuclear products were found in irradiated foods were Na-24, P-32, Ca-45, C-11, N-13, and O-15 in the food irradiated by 24 MeV electron beam. The total radioactivity is less than 1/1000 of those of K-40 in the case of electron beams below 10 MeV or X rays below 5 MeV. Package materials affected neutron flux in the foods and enhanced the radioactivity. Electron beam machine produces neutrons and increases the flux in food. IAEA recommend to reduce neutron production in the facility. The safety of irradiated food in the radioactivity field still needs more progress. (author)

  15. Effect of etching morphology of artificial defect on laser-induced damage properties under 355??nm laser irradiation.

    Science.gov (United States)

    Ma, Bin; Lu, Menglei; Zhan, Guangda; Wang, Ke; Cheng, Xinbin; Wang, Zhanshan

    2015-04-10

    Structural defects and absorptive impurities generated in the process of grinding and polishing optical substrates before coating significantly lower the resistance of optical elements to laser. Thus, artificial defects that contain indentations and absorptive particles are fabricated in this study. Chemical etching is used to examine the morphology and depth of artificial defects with different sizes and types under various etching times. Moreover, the transverse and longitudinal sizes, as well as the morphology, of defects are determined to analyze the damage properties of artificial defects under 355 nm of laser irradiation. Finally, the differences in the artificial defects induced by various materials are discussed along with their influences on damage properties. PMID:25967325

  16. IRACM : A code system to calculate induced radioactivity produced by ions and neutrons

    International Nuclear Information System (INIS)

    It is essential to estimate of radioactivity induced in accelerator components and samples bombarded by energetic ion beams and the secondary neutrons of high-energy accelerator facilities in order to reduce the amount of radioactive wastes and to minimize radiation exposure to personnel. A computer code system IRACM has been developed to estimate product nuclides and induced radioactivity in various radiation environments of accelerator facilities. Nuclide transmutation with incident particles of neutron, proton, deuteron, alpha, 12C, 14N, 16O, 20Ne and 40Ar can be computed for arbitrary multi-layer target system in a one-dimensional geometry. The code system consists of calculation modules and libraries including activation cross sections, decay data and photon emission data. The system can be executed in both FACOM-M780 mainframe and DEC workstations. (author)

  17. Structure effects on reaction mechanisms in collisions induced by radioactive ion beams

    International Nuclear Information System (INIS)

    The present paper concerns the study of reactions induced by radioactive beams of halo and weakly bound nuclei at energies around and above the Coulomb barrier. The results obtained for the reaction induced by the halo nucleus 6He on 64Zn have been compared with the results for the reaction induced by 4He on the same target. The results of the reaction induced by the weakly bound unstable 13N on the weakly bound 9Be have been compared with those for the reaction 10B + 12C

  18. Effect of etching on the laser-induced damage properties of artificial defects under 1064-nm laser irradiation

    Science.gov (United States)

    Lu, Menglei; Ma, Bin; Zhan, Guangda; Jiao, Hongfei; Cheng, Xinbin

    2014-12-01

    The cracks and scratches inevitably generated by previous grinding and polishing significantly lower the ability of laser resistance of optical substrates. In this study, the artificial indentations, scratches, and structural defects imbedded with metal nanoparticles are fabricated. The laser-induced damage characteristics of such defects in different types and sizes are investigated qualitatively and quantitatively under 1064-nm laser irradiation. Moreover, the etching effect on improving the laser-induced damage threshold (LIDT) of artificial defects under different etching conditions is analyzed. LIDT is then evaluated according to the etching depth and the morphologies of artificial defects.

  19. Sunlight-induced pyrimidine dimers in human skin fibroblasts in comparison with dimerization after artificial UV-irradiation

    International Nuclear Information System (INIS)

    We compared artificial UV-sources such as germicidal- or sun-lamps with summer noon sunlight in Switzerland for selective efficiency in the induction of pyrimidine dimers in the DNA of human cells. In our studies we determined cytosine-thymine (C-T) as well as thymine-thymine dimer densities (T-T) by high pressure liquid chromatography in cultures of xeroderma pigmentosum cells of group A. Using far-UV light from a germicidal lamp, we found a rate of formation per Jm-2 for C-T and T-T of 0.0019% and 0.0024%, respectively, of the total thymine radioactivity in hydrolysates of [3H]thymidine labeled cells. After irradiation with an unfiltered sunlamp, we measured a rate of formation of 0.0005% per Jm-2 both for C-T and T-T, based on the sunlamp emission of 297 ± 4 nm wavelength. Utilization of Kodacel- or Mylar-filters lowered the rate of dimerization by a factor of 2 and 60, respectively. One hour of irradiation with noon summer sunlight induced 0.038 ± 0.012% C-T and 0.036 ± 0.011% T-T. This extent of dimer production is equivalent to 15 Jm-2 of far-UV exposure at 254 nm. (author)

  20. Magnitude, course of time and correlations of the total, lead and artificially radioactive suspended dust pollutants in a stress border area

    International Nuclear Information System (INIS)

    The average total suspended dust concentration of 56 ?g/m3 in the stress border area around Iserlon lies within the range of the clean air area values and amounts only to about the half the mean value in the Ruhr stress area. The mean lead suspended dust stress of 0.21 ?g/m3, however, is about 8 times higher than in the clean air areas and about 3 times lower than in the stress area. On sundays the total suspended dust concentration is reduced to 82% and the lead suspended dust concentration to 40% of the week-day value. The artificial suspended dust radioactivity seems to be within the range of the average in West Germany. Lead concentration and suspended dust radioactivity are far extendingly independent of the total suspended dust stress. (orig.)

  1. Five new eudesmane-type sesquiterpenoids from Chinese agarwood induced by artificial holing.

    Science.gov (United States)

    Li, Wei; Cai, Cai-Hong; Guo, Zhi-Kai; Wang, Hao; Zuo, Wen-Jian; Dong, Wen-Hua; Mei, Wen-Li; Dai, Hao-Fu

    2015-01-01

    Five new eudesmane-type sesquiterpenoids (1-5), along with six known ones (6-11), were isolated from Chinese agarwood induced by artificial holing originating from Aquilaria sinensis (Lour.) Gilg (Thymelaeaceae). The structures of the new sesquiterpenoids were established by spectroscopic methods including UV, IR, MS, 1D, and 2D NMR. Compounds 1, 3, 6 and 7 exhibited antibacterial activities against both Staphylococcus aureus and Ralstonia solanacearum, and compound 5 only showed an inhibitory activity towards S. aureus. Compounds 1, 6, 7 and 10 showed weak acetylcholinesterase inhibitory activity. PMID:25447164

  2. Prediction of radiation induced hardening of reactor pressure vessel steels using artificial neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Castin, N., E-mail: ncastin@sckcen.b [Studie Centrum voor Kerneenergie - Centre d' Etudes de l' energie Nucleaire (SCK-CEN), NMS unit, Boeretang 200, B2400, Mol (Belgium); Universite Libre de Bruxelles (ULB), Physique des Solides Irradies et des Nanostructures (PSIN), Boulevard du Triomphe CP234, 1050 Brussels (Belgium); Malerba, L.; Chaouadi, R. [Studie Centrum voor Kerneenergie - Centre d' Etudes de l' energie Nucleaire (SCK-CEN), NMS unit, Boeretang 200, B2400, Mol (Belgium)

    2011-01-01

    In this paper, we use an artificial neural network approach to obtain predictions of neutron irradiation induced hardening, more precisely of the change in the yield stress, for reactor pressure vessel steels of pressurized water nuclear reactors. Different training algorithms are proposed and compared, with the goal of identifying the best procedure to follow depending on the needs of the user. The numerical importance of some input variables is also studied. Very accurate numerical regressions are obtained, by taking only four input variables into account: neutron fluence, irradiation temperature, and chemical composition (Cu and Ni content). Accurate extrapolations in term of neutron fluence are obtained.

  3. Radioactivity. Centenary of radioactivity discovery

    International Nuclear Information System (INIS)

    This small booklet was edited for the occasion of the exhibitions of the celebration of the centenary of radioactivity discovery which took place in various locations in France from 1996 to 1998. It recalls some basic knowledge concerning radioactivity and its applications: history of discovery, atoms and isotopes, radiations, measurement of ionizing radiations, natural and artificial radioactivity, isotope dating and labelling, radiotherapy, nuclear power and reactors, fission and fusion, nuclear wastes, dosimetry, effects and radioprotection. (J.S.)

  4. Artificial neural network for on-site quantitative analysis of soils using laser induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Nowadays, due to environmental concerns, fast on-site quantitative analyses of soils are required. Laser induced breakdown spectroscopy is a serious candidate to address this challenge and is especially well suited for multi-elemental analysis of heavy metals. However, saturation and matrix effects prevent from a simple treatment of the LIBS data, namely through a regular calibration curve. This paper details the limits of this approach and consequently emphasizes the advantage of using artificial neural networks well suited for non-linear and multi-variate calibration. This advanced method of data analysis is evaluated in the case of real soil samples and on-site LIBS measurements. The selection of the LIBS data as input data of the network is particularly detailed and finally, resulting errors of prediction lower than 20% for aluminum, calcium, copper and iron demonstrate the good efficiency of the artificial neural networks for on-site quantitative LIBS of soils. - Highlights: ? We perform on-site quantitative LIBS analysis of soil samples. ? We demonstrate that univariate analysis is not convenient. ? We exploit artificial neural networks for LIBS analysis. ? Spectral lines other than the ones from the analyte must be introduced

  5. Measurements of fusion reactions induced by radioactive 132Sn on 64Ni

    Energy Technology Data Exchange (ETDEWEB)

    Liang, J Felix [ORNL; Shapira, Dan [ORNL; Gross, Carl J [ORNL; Varner Jr, Robert L [ORNL; Amro, H [University of Notre Dame, IN; Beene, James R [ORNL; Bierman, Jeff D [Gonzaga University; Caraley, Anne L [State University of New York, Oswego; Galindo-Uribarri, Alfredo {nmn} [ORNL; Gomez Del Campo, Jorge [ORNL; Hausladen, Paul [ORNL; Jones, K. L. [Rutgers University; Kolata, Jim J [University of Notre Dame, IN; Larochelle, Y [University of Tennessee, Knoxville (UTK); Loveland, Walter [Oregon State University; Mueller, Paul Edward [ORNL; Peterson, Don [Oregon State University; Radford, David C [ORNL; Stracener, Daniel W [ORNL

    2007-01-01

    Evaporation residue and fission cross sections of radioactive 132Sn on 64Ni were measured. Statistical model calculations using parameters simultaneously fitting stable Sn+64Ni data reproduce the 132Sn induced reaction very well. A large sub-barrier fusion enhancement was observed. The enhancement can be accounted for by coupled-channels calculations including inelastic excitation of the projectile and target, and neutron transfer.

  6. Proton induced radioactivity estimation and radiological safety aspects of materials science beam line at medical cyclotron

    International Nuclear Information System (INIS)

    A medical cyclotron facility is under development in Kolkata. This medical cyclotron would deliver 15 - 30 MeV H+ ions with beam current up to 500 ?A. Though this facility will be mainly used for production of medically useful isotopes, a beam line has been also provided for materials science research. The materials science beam line will be used to study radiation damage in nuclear materials. Apart from radiation damage studies, material science beam line will be used for thin layer activation analysis, charged particle activation analysis and production of special isotopes. High intensity proton beam in this energy regime can induce high level of radioactivity in the target material and other beam line components. Hence it is necessary to calculate the induced radioactivity for a variety of materials, so as to find a suitable candidate for use in beam line components, to design radiation shielding and to design proper target handling devices and shielding arrangements. There are two ways by which radioactivity in beam line components can be induced, either by direct interaction of proton beam or by neutrons emitted from target during irradiation. The cross-section of production of various radionuclides and neutrons at different energies produced as a result of nuclear reaction between proton and target atoms has been generated using ALICE code. These cross-sections are used to calculate concentration of radionuclides and emitted neutron spectrum. The decay scheme of radionuclides is taken from Universal Nuclide Chart. Neutron induced activity in target chamber is estimated using MCNP code. These calculations have found to be very useful in the material selection for beam line components and designing radiation shielding. Various aspects of radioactivity calculations and radiological safety on material science beam line will be discussed. (author)

  7. Percutaneous CT-Guided Ablation in the Hepatic Dome: Artificially Induced Pneumothorax for Safe Transpleural Access

    Science.gov (United States)

    Valle, Leonardo Guedes Moreira; Rochal, Rafael Dahmer; Rahal, Antônio; Garcia, Rodrigo Gobbo

    2015-01-01

    Ablative therapies have become a great alternative to surgical treatment of hepatic nodules. Some technical difficulties may negatively influence the effectiveness of this therapy, such as lesions located near the diaphragm. The transthoracic approach is commonly used to access these lesions. However, it is associated with an increased risk of complications, such as pneumothorax, hemothorax, alveolar bleeding, and others. We report a case of a radiofrequency ablation of a lesion in the hepatic dome, where an artificially induced pneumothorax was performed to guarantee a safe and effective access. The air was easily injected by a spinal needle and later aspirated by a single-lumen catheter. Induced pneumothorax shoud be considered in ablation of hepatic dome lesions, mainly when the transhepatic access is not appropriate.

  8. A radiation-induced breast cancer following artificial pneumothorax therapy for pulmonary tuberculosis

    International Nuclear Information System (INIS)

    A case of radiation-induced breast cancer in a woman who had been fluoroscopied repeatedly for control of pneumothorax for pulmonary tuberculosis 35 years before is reported. The breast tissue presumably received about 136 rads or less in three and a half years. In Japan, both prospective and retrospective surveies following multiple fluoroscopies during artificial pneumothorax collaps therapy have failed to show an increase in the risk of subsequent development of primary breast cancer. The dose given to breast tissues in Japanese patients was generally far less than that in the MacKenzie's series. A radiation-induced breast cancer in Japanese literature has not yet been reported. It seems that the lesser doses may explain the reason of this fact. (auth.)

  9. Percutaneous CT-Guided Ablation in the Hepatic Dome: Artificially Induced Pneumothorax for Safe Transpleural Access.

    Science.gov (United States)

    Valle, Leonardo Guedes Moreira; Rochal, Rafael Dahmer; Rahal, Antônio; Garcia, Rodrigo Gobbo

    2015-01-01

    Ablative therapies have become a great alternative to surgical treatment of hepatic nodules. Some technical difficulties may negatively influence the effectiveness of this therapy, such as lesions located near the diaphragm. The transthoracic approach is commonly used to access these lesions. However, it is associated with an increased risk of complications, such as pneumothorax, hemothorax, alveolar bleeding, and others. We report a case of a radiofrequency ablation of a lesion in the hepatic dome, where an artificially induced pneumothorax was performed to guarantee a safe and effective access. The air was easily injected by a spinal needle and later aspirated by a single-lumen catheter. Induced pneumothorax shoud be considered in ablation of hepatic dome lesions, mainly when the transhepatic access is not appropriate. PMID:26713179

  10. Influence of ion bombardment induced patterning of exchange bias in pinned artificial ferrimagnets on the interlayer exchange coupling

    International Nuclear Information System (INIS)

    Artificial ferrimagnets (AFi) have many applications as, e.g., pinned reference electrodes in magnetic tunnel junctions. It is known that the application of ion bombardment induced magnetic patterning with He ions on a single layer reference electrode of magnetic tunnel junctions is possible. For some applications a combination of ion bombardment induced magnetic patterning and artificial ferrimagnets as a reference electrode is desirable. The effect of ion bombardment induced magnetic patterning on pinned artificial ferrimagnets with a Ru interlayer which is frequently used in magnetic tunnel junctions as well as pinned AFis with a Cu interlayer has been tested. Special attention has been given to the question whether the antiferromagnetic interlayer exchange coupling can withstand the ion dose necessary to turn the exchange bias

  11. DCHAIN-SP 2001: High energy particle induced radioactivity calculation code

    Energy Technology Data Exchange (ETDEWEB)

    Kai, Tetsuya; Maekawa, Fujio; Kasugai, Yoshimi; Takada, Hiroshi; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kosako, Kazuaki [Sumitomo Atomic Energy Industries, Ltd., Tokyo (Japan)

    2001-03-01

    For the purpose of contribution to safety design calculations for induced radioactivities in the JAERI/KEK high-intensity proton accelerator project facilities, the DCHAIN-SP which calculates the high energy particle induced radioactivity has been updated to DCHAIN-SP 2001. The following three items were improved: (1) Fission yield data are included to apply the code to experimental facility design for nuclear transmutation of long-lived radioactive waste where fissionable materials are treated. (2) Activation cross section data below 20 MeV are revised. In particular, attentions are paid to cross section data of materials which have close relation to the facilities, i.e., mercury, lead and bismuth, and to tritium production cross sections which are important in terms of safety of the facilities. (3) User-interface for input/output data is sophisticated to perform calculations more efficiently than that in the previous version. Information needed for use of the code is attached in Appendices; the DCHAIN-SP 2001 manual, the procedures of installation and execution of DCHAIN-SP, and sample problems. (author)

  12. DCHAIN-SP 2001: High energy particle induced radioactivity calculation code

    International Nuclear Information System (INIS)

    For the purpose of contribution to safety design calculations for induced radioactivities in the JAERI/KEK high-intensity proton accelerator project facilities, the DCHAIN-SP which calculates the high energy particle induced radioactivity has been updated to DCHAIN-SP 2001. The following three items were improved: (1) Fission yield data are included to apply the code to experimental facility design for nuclear transmutation of long-lived radioactive waste where fissionable materials are treated. (2) Activation cross section data below 20 MeV are revised. In particular, attentions are paid to cross section data of materials which have close relation to the facilities, i.e., mercury, lead and bismuth, and to tritium production cross sections which are important in terms of safety of the facilities. (3) User-interface for input/output data is sophisticated to perform calculations more efficiently than that in the previous version. Information needed for use of the code is attached in Appendices; the DCHAIN-SP 2001 manual, the procedures of installation and execution of DCHAIN-SP, and sample problems. (author)

  13. Computational Analysis of Artificial Gravity as a Possible Countermeasure to Spaceflight Induced Bone Loss

    Science.gov (United States)

    Mulugeta, L.; Werner, C. R.; Pennline, J. A.

    2015-01-01

    During exploration class missions, such as to asteroids and Mars, astronauts will be exposed to reduced gravity for extended periods. Data has shown that astronauts lose bone mass at a rate of 1% to 2% a month in microgravity, particularly in lower extremities such as the proximal femur. Exercise countermeasures have not completely eliminated bone loss from long duration spaceflight missions, which leaves astronauts susceptible to early onset osteoporosis and greater risk of fracture. Introduction of the Advanced Resistive Exercise Device and other large exercise devices on the International Space Station (ISS), coupled with improved nutrition, has further minimized bone loss. However, unlike the ISS, exploration vehicles will have very limited volume and power available to accommodate such capabilities. Therefore, novel concepts like artificial gravity systems are being explored as a means to provide sufficient load stimulus to the musculoskeletal system to mitigate bone changes that may lead to early onset osteoporosis and increased risk of fracture. Currently, there is minimal data available to drive further research and development efforts to appropriately explore such options. Computational modeling can be leveraged to gain insight on the level of osteoprotection that may be achieved using artificial gravity produced by a spinning spacecraft or centrifuge. With this in mind, NASA's Digital Astronaut Project (DAP) has developed a bone remodeling model that has been validated for predicting volumetric bone mineral density (vBMD) changes of trabecular and cortical bone both for gravitational unloading condition and the equivalent of 1g daily load stimulus. Using this model, it is possible to simulate vBMD changes in trabecular and cortical bone under different gravity conditions. In this presentation, we will discuss our preliminary findings regarding if and how artificial gravity may be used to mitigate spaceflight induced bone loss.

  14. Investigation of induced radioactivity in the CERN Large Electron Positron collider for its decommissioning

    Science.gov (United States)

    Silari, Marco; Ulrici, Luisa

    2004-07-01

    The future installation of the Large Hadron Collider in the tunnel formerly housing the Large Electron Positron collider (LEP) required the dismantling of the latter after 11-year operation. As required by the French legislation, an extensive theoretical study was conducted before decommissioning to establish the possible activation paths both in the accelerator and in the four experiments (L3, ALEPH, OPAL and DELPHI) installed around the ring. The aim was to define which areas may contain activated material and which ones would be completely free of activation. The four major sources of activation in LEP, i.e., distributed and localized beam losses, synchrotron radiation and the super-conducting RF cavities, were investigated. Conversion coefficients from unit lost beam power to induced specific activity were established for a number of materials. A similar study was conducted for the four experiments, evaluating the four potential sources of induced radioactivity, namely e +e - annihilation events, two-photon events, e +e - Bhabha scattering events and beam-related radiation, i.e., synchrotron radiation and off-momentum beam particles. Decommissioning started early in 2001 and was completed by February 2002. Every single piece removed from the machine tunnel and experimental areas was double-checked for induced radioactivity, with complementary gamma-spectrometry measurements performed on samples of the various materials. The measurements have to a large extent confirmed the predictions. The overall intent of this paper is to provide data and computational guidelines for assessing induced radioactivity in high-energy electron accelerators, which could be of use in future decommissioning.

  15. Investigation of induced radioactivity in the CERN Large Electron Positron collider for its decommissioning

    International Nuclear Information System (INIS)

    The future installation of the Large Hadron Collider in the tunnel formerly housing the Large Electron Positron collider (LEP) required the dismantling of the latter after 11-year operation. As required by the French legislation, an extensive theoretical study was conducted before decommissioning to establish the possible activation paths both in the accelerator and in the four experiments (L3, ALEPH, OPAL and DELPHI) installed around the ring. The aim was to define which areas may contain activated material and which ones would be completely free of activation. The four major sources of activation in LEP, i.e., distributed and localized beam losses, synchrotron radiation and the super-conducting RF cavities, were investigated. Conversion coefficients from unit lost beam power to induced specific activity were established for a number of materials. A similar study was conducted for the four experiments, evaluating the four potential sources of induced radioactivity, namely e+e- annihilation events, two-photon events, e+e- Bhabha scattering events and beam-related radiation, i.e., synchrotron radiation and off-momentum beam particles. Decommissioning started early in 2001 and was completed by February 2002. Every single piece removed from the machine tunnel and experimental areas was double-checked for induced radioactivity, with complementary gamma-spectrometry measurements performed on samples of the various materials. The measurements have to a large extent confirmed the predictions. The overall intent of this paper is to provide data and computational guidelines for assessing induced radioactivity in high-energy electron accelerators, which could be of use in future decommissioning

  16. Induced radioactivities and cross section measurements of the 14 MeV irradiated molybdenum foils

    International Nuclear Information System (INIS)

    The radioactivities of 14 MeV neutron irradiated Molybdenum foils have been measured for comparison exercise conducted by the IAEA Nuclear Data Section. The spectra of the characteristic gamma-rays emitted as a result of the induced radioactivity were taken with a Ge(Li) detector and an Intrinsic Germanium detector. The cross sections for the reaction 92Mo(n,np)91mNb, 95Mo(n,p)95Nb and 98Mo(n,?)95Zr have been determined using the information provided by the IAEA on the irradiation time, total fluence and masses of the irradiated foils. The activation cross sections determined from the present measurements have been compared with previous work. (author). 8 refs, figs, 3 tabs

  17. Development of the two-phase flow induced force fluctuation predictive tool using artificial void signal

    International Nuclear Information System (INIS)

    In this study, fluctuating force acting on pipe turning section due to two-phase flow is considered. A novel tool to predict upward two-phase flow induced force fluctuations is developed. In order to eliminate tool's dependencies on experimental measurement input, creation of artificial void signal (AVS) was considered by carefully analyzing area-averaged void fraction properties, including probability density and frequency spectra from 36 flow conditions. Generated AVS was successfully coupled with the predictive tool, and as a result, it is capable of predicting fluctuating force magnitude and dominant force frequency from the inlet superficial velocities alone. The tool is applicable for small inner diameter pipe (

  18. Identification of polymer materials using laser-induced breakdown spectroscopy combined with artificial neural networks.

    Science.gov (United States)

    Boueri, Myriam; Motto-Ros, Vincent; Lei, Wen-Qi; Ma, Qain-Li; Zheng, Li-Juan; Zeng, He-Ping; Yu, Jin

    2011-03-01

    A combination of laser-induced breakdown spectroscopy (LIBS) and artificial neural networks (ANNs) has been used for the identification of polymer materials, including polypropylene (PP), polyvinyl chloride (PVC), polytetrafluoroethylene (PTFE), polyoxymethylene (POM), polyethylene (PE), polyamide or nylon (PA), polycarbonate (PC) and poly(methyl methacrylate) (PMMA). After optimization of the experimental setup and the spectrum acquisition protocol, successful identification rates between 81 and 100% were achieved using spectral features gathered from single spectra without averaging (1 second acquisition time) over a wide spectral range (240-820 nm). Furthermore, ten different materials based on PVC were tested using the identification procedure. Correct identifications were obtained as well. Sorting of the materials into sub-categories of PVC materials according to their charges (concentration in trace elements such as Ca) was performed. The demonstrated capacities fit, in practice, the needs of plastic-waste sorting and of producing high-grade recycled plastic materials. PMID:21352651

  19. Antitussive effect of dextromethorphan and dextromethorphan-salbutamol combination in healthy volunteers with artificially induced cough.

    Science.gov (United States)

    Karttunen, P; Tukiainen, H; Silvasti, M; Kolonen, S

    1987-01-01

    The antitussive effects of dextromethorphan (30 mg) + salbutamol (2 mg), dextromethorphan (30 mg) alone and placebo on artificial cough induced by citric acid were compared in 19 healthy non-smoking volunteers in a double-blind crossover study. The method using inhaled citric acid with increasing concentrations to establish the cough threshold level showed an acceptable reproducibility and proved to be suitable for comparison of antitussive drugs. The cough threshold level was assessed before as well as 90 and 180 min after each medication. After placebo the cough threshold level showed no statistically significant rise. However, significant rises were shown following dextromethorphan (p less than 0.001) and the dextromethorphan-salbutamol combination (p less than 0.001). Between the treatments significant differences were shown in favour of the dextromethorphan-salbutamol combination. The results indicate that salbutamol has antitussive action enhancing the effect of plain dextromethorphan. PMID:3659583

  20. Bluelight-induced, flavin-mediated transport of redox equivalents across artificial bilayer membranes

    International Nuclear Information System (INIS)

    This paper continues studies of physico-chemical properties of vesicle-bound flavins. Based on previous results, an advanced model system was designed in order to study the mechanisms underlying bluelight-induced redox transport across artificial membranes. The lumen of single-shelled vesicles was charged with cytochrome c, and amphiphilic flavin (AF1 3, AF1 10) was bound to the membrane. Upon bluelight irradiation redox equivalents are translocated from exogeneous 1e-(EDTA)-and 2e-(BH3CN-) donors across the membrane finally reducing the trapped cytochrome c both under aerobic and anaerobic conditions. The mechanisms involved are explored and evidence for the involvement of various redox states of oxygen, dihydroflavin and flavosemiquinone is presented

  1. Application of artificial neural networks on the characterization of radioactive waste drums; Aplicacao de redes neurais artificiais na caracterizacao de tambores de rejeito radioativo

    Energy Technology Data Exchange (ETDEWEB)

    Potiens Junior, Ademar Jose; Hiromoto, Goro, E-mail: apotiens@ipen.b, E-mail: hiromoto@ipen.b [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2011-10-26

    The methodology consist of system simulation of drum-detector by Monte Carlo for obtention of counting efficiency. The obtained data were treated and a neural artificial network (RNA) were constructed for evaluation of total activity of drum. For method evaluation measurements were performed in ten position parallel to the drum axis and the results submitted to the RNA. The developed methodology showed to be effective for isotopic characterization of gamma emitter radioactive wastes distributed in a heterogeneous way in a 200 litters drum. The objective of this work as to develop a methodology of analyse for quantification and localization of radionuclides not homogeneous distributed in a 200 liters drum based on the mathematical techniques

  2. Environmental radioactivity in Caithness and Sutherland. Pt. 10: Studies of artificial radioactivity in the coastal environment of Northern Scotland: a review

    International Nuclear Information System (INIS)

    This review brings together measurements which have been made over the last 10-15 years of the concentrations of a number of artificial radionuclides in various media in the northern Scottish coastal environment. The radionuclides include 60Co, 90Sr, 134Cs, 137Cs, 238Pu, 239,240Pu and 241Am. The media include nearshore and offshore seawater, beach sand and sediments, seaweeds, winkles, spume, deposits on rocks and soils, sheep faeces and atmospheric deposition. The various radionuclide sources which contribute to the study area are described. Some transfer mechanisms which operate between different media for different radionuclides are discussed, and the radiological significance of the observed radionuclide concentrations is briefly described. (UK)

  3. Selection and investigation of sites for the disposal of radioactive wastes in hydraulically induced subsurface fractures

    International Nuclear Information System (INIS)

    Injection of intermediate-level radioactive wastes (specific activity of less than 6 x 103 ?Ci/mL, consisting mainly of radionuclides, such as strontium and cesium, having half-lives of less than 50 years) mixed with cement into a thick shale formation is a promising and feasible disposal method. Hydraulic fracturing provides openings in the shale to accommodate the wastes. Ion exchange and radionuclide-adsorption materials can be added to the grout during mixing to further increase the radionuclide-retaining capacity of the grout. After solidification of the grout, the injected wastes become an integral part of the shale formation, and therefore the wastes will remain at depth and in place as long as the injection zone is not subjected to erosion and dissolution. Problems concerning safety of the disposal method are (1) the potential for inducing vertical fractures, (2) phase separation during and after the injections, (3) the reliability of methods for determining the orientation of induced fractures, (4) the possibility of triggering earthquakes, and (5) radionuclides being leached and transported by ground water. Theoretical considerations about inducing nearly horizontal bedding-plane fractures in shale are discussed, as are field procedures for site selection, safety, and the monitoring and operation of radioactive waste disposal. Case histories are used as examples to demonstrate the application of the theory and techniques of field operations

  4. High energy proton-induced radioactivity in HgI2 crystals

    International Nuclear Information System (INIS)

    Mercuric iodide (HgI2) semiconductor crystals are generating a lot of interest as room temperature solid state detectors for hard X-ray astronomy observations. For these applications one of the most important background sources is the cosmic proton induced radioactivity in the detector material. In order to study this background noise contribution a 1x1x1 cm HgI2 crystal was irradiated with high energy protons. The resulting long-lived unstable isotopes and their production rates have been identified and compared with Monte Carlo simulations. ((orig.))

  5. Calculation of radioactivity induced in gamma-ray spectrometers during spaceflight

    International Nuclear Information System (INIS)

    Radioactivity induced in detector materials by cosmic rays, trapped protons and secondary neutrons is a major source of background in gamma-ray astronomy and remote sensing spectroscopy of the moon and the planets. A calculation scheme for assessing this component has been developed based on semi-empirical cross-sections and stochastic calculations of energy-loss spectra of radioactive nuclides. In addition, predictive methods are available based on experimental data obtained from monoenergetic proton beam irradiations of scintillators at energies of 155, 600, 800 MeV and 6 GeV. Application of these methods to in-flight results from scintillator detectors carried on lightweight OSO spacecraft, for which trapped protons of 20-200 MeV dominate, shows that the induced radiactivity at lower photon energies can be well explained by spallation interactions of primary protons in the central crystal detector elements. The contributions to the induced activity due to collimators, materials surrounding the detector, and the spacecraft become increasingly important at higher proton energies. For such detectors carried on the Apollo missions, the more energetic (> 300 MeV) cosmic-ray flux dominates. The library of isotopes presently used can predict only about half the induced radiactivity, and corrections for missing radionuclides must be based on the experimental irradiation results. Results from crystals returned to Earth from Apollo 17 and Apollo-Soyuz show that, for heavy spacecraft, secondary neutrons can significantly enchance the background. Preliminary estimates have been made of the important gamma-ray line features to be expected from cosmic-ray and trapped proton induced spallation products in germanium detectors. (orig.)

  6. Measurement of fertilizers induced radioactivity in tobacco plants and elemental analysis using ICAP–AES

    International Nuclear Information System (INIS)

    It is widely accepted that tobacco smoke is the leading cause of lung cancer worldwide. The alpha radioactive content present in tobacco smoke and increasing number of lung cancer cases explain the importance of investigation. The use of different fertilizers may cause alteration in the metabolism of plants causing different response towards uptake of different element and radionuclides. In the present study, the estimation of alpha radioactivity induced by use of different fertilizers in tobacco leaves was made using solid state nuclear track detector (LR-115) to identify the relative presence of radionuclides in the plants. The radon exhalation rates from the tobacco plant were carried out to confirm the presence of radium or emission of radon from plant. The elemental analysis of tobacco plant by inductively coupled argon plasma atomic emission spectrometry provides a way to understand the difference occurred in metabolism caused by the use of fertilizers. The alpha track densities were found to vary with nature of fertilizers added to the soil and an increase was also observed with time. The radon mass exhalation rates in various tobacco plants were found to vary with type of fertilizers used. - Highlights: • The study is related to alpha radioactivity measurements in tobacco plants. • The radon mass exhalation rates in various tobacco plants were also measured. • Study is related to analysis of chemical elements in different fertilized tobacco samples

  7. Plant height reduction in populations of triticale (X triticosecale Wittmack by induced mutations and artificial crosses

    Directory of Open Access Journals (Sweden)

    Fábio Pandini

    1997-09-01

    Full Text Available Induced mutations by gamma radiation (0, 5, 10, 20 and 40 kR doses and reciprocal crosses were tested as mechanisms of enhancing genetic variability for plant height in two triticale cultivars, BR4 and EMBRAPA18. The reciprocal crosses and all doses of radiation showed similar increase in genetic amplitude for this trait, being suitable for increasing variability in breeding programs. Genotypes showed different responses as the gamma ray doses were increased, expressing shorter plant height. The decision of using induced mutations or artificial crosses depends on the resources available and the selection method to be usedMutações induzidas pelo uso das doses de radiação gama 0, 5, 10, 20 e 40 kR e cruzamentos artificiais recíprocos foram testados como mecanismos para aumentar a variabilidade genética em duas cultivares de triticale, BR4 e EMBRAPA18. Os tratamentos empregados provocaram amplitudes similares de variabilidade genética, com alterações nas médias e variâncias, podendo favorecer o emprego da seleção na obtenção de genótipos superiores. As respostas dos genótipos foram diferenciadas, sendo mais acentuadas quando submetidos a doses superiores do tratamento mutagênico, determinando uma redução na estatura. Em relação ao nível de variabilidade genética obtida, os tratamentos mutagênicos foram tão eficientes quanto as hibridações artificiais. A decisão do método a ser utilizado deve ser adequada aos recursos disponíveis, assim como o mecanismo mais eficiente de seleção para os caracteres de interesse

  8. Cosmic-ray induced production of radioactive noble gases in the atmosphere, ground, and seawater

    International Nuclear Information System (INIS)

    This paper describes the development of an MCNP6 model and a suite of supporting MATLAB scripts being developed to conduct detailed studies of the radioactive noble gas background activity concentrations resulting from cosmic-neutron-induced reactions in the Earth's atmosphere, in various geologies, and in seawater. Initial results generated using the MCNP6 model and the suite of supporting MATLAB scripts indicate that the cosmic-neutron-induced 133Xe background activity concentrations at a depth of 1 m in a geology representative of the Earth's upper crust and a depth of 5 m in seawater are about 3.48 × 10-1 and 8.49 × 10-7 mBq m-3, respectively. (author)

  9. Investigation of induced radioactivity in the CERN Large Electron Positron collider for its decommissioning

    CERN Document Server

    Silari, Marco

    2004-01-01

    The future installation of the Large Hadron Collider in the tunnel formerly housing the Large Electron Positron collider (LEP) required the dismantling of the latter after 11-year operation. As required by the French legislation, an extensive theoretical study was conducted before decommissioning to establish the possible activation paths both in the accelerator and in the four experiments (L3, ALEPH, OPAL and DELPHI) installed around the ring. The aim was to define which areas may contain activated material and which ones would be completely free of activation. The four major sources of activation in LEP, i.e., distributed and localized beam losses, synchrotron radiation and the super-conducting RF cavities, were investigated. Conversion coefficients from unit lost beam power to induced specific activity were established for a number of materials. A similar study was conducted for the four experiments, evaluating the four potential sources of induced radioactivity, namely e**+e **- annihilation events, two-p...

  10. Influence of ion bombardment induced patterning of exchange bias in pinned artificial ferrimagnets on the interlayer exchange coupling

    International Nuclear Information System (INIS)

    Artificial ferrimagnets have many applications as, e.g., pinned reference electrodes in magnetic tunnel junctions. It is known that the application of ion bombardment (IB) induced patterning of the exchange bias coupling of a single layer reference electrode in magnetic tunnel junctions with He ions is possible. For applications as, e.g., special types of magnetic logic, a combination of the IB induced patterning of the exchange bias coupling and the implementation of an artificial ferrimagnet as reference electrode is desirable. Here, investigations for a pinned artificial ferrimagnet with a Ru interlayer, which is frequently used in magnetic tunnel junctions, are presented. It is shown that in this kind of samples the exchange bias can be increased or rotated by IB induced magnetic patterning with 10 keV He ions without a destruction of the antiferromagnetic interlayer exchange coupling. An IrMn/Py/Co/Cu/Co stack turned out to be more sensitive to the influence of IB than the Ru based artificial ferrimagnet

  11. The use of an experimental device for the determination of the concentration of artificial radioactive aerosols at high altitudes

    International Nuclear Information System (INIS)

    By means of measurements with a Geiger counter on january, the 27th, in 1959 at an altitude reaching 65 km approximately, and following comparison with similar measurements made by Gangnes, Jenkins and Van Allen in 1949 at the same geomagnetic latitude (41 deg. North), it is concluded that radioactive aerosols above Southern France tropopause had a concentration less than 100.10-12 curies/m3 at that time. The missile used for this purpose and its performance are quickly described in this paper. (author)

  12. Induced radioactivity analysis for the NSRL Linac in China using Monte Carlo simulations and gamma-spectroscopy

    CERN Document Server

    He, Lijuan; Li, Weimin; Chen, Zhi; Chen, Yukai; Ren, Guangyi

    2014-01-01

    The 200-MeV electron linac of the National Synchrotron Radiation Laboratory (NSRL) located in Hefei is one of the earliest high-energy electron linear accelerators in China. The electrons are accelerated to 200 MeV by five acceleration tubes and are collimated by scrapers. The scraper aperture is smaller than the acceleration tube one, so some electrons hit the materials when passing through them. These lost electrons cause induced radioactivity mainly due to bremsstrahlung and photonuclear reaction. This paper describes a study of induced radioactivity for the NSRL Linac using FLUKA simulations and gamma-spectroscopy. The measurements showed that electrons were lost mainly at the scraper. So the induced radioactivity of the NSRL Linac is mainly produced here. The radionuclide types were simulated using the FLUKA Monte Carlo code and the results were compared against measurements made with a High Purity Germanium (HPGe) gamma spectrometer. The NSRL linac had been retired because of upgrading last year. The re...

  13. Alternatives of applications in the information taking with artificial radioactive tools in the mature fields of the South region

    International Nuclear Information System (INIS)

    In this work it is widely described the application of the saturation control tool (RST) used in the campo Rodador (Mexico), and shortly the registration tools of location monitoring (RMT) and the Monitor tool of the location operation (RPM) used for the evaluation in site of the mature wells, had being at the present time these three tools with nuclear reaction mechanisms to obtain the water saturation and of hydrocarbon by means of the Neutron capture (PNC) and Inelastic scattering (IS). Both tools have been designed to help to the evaluation of the mature wells in the locations. Starting from measurements made through the lining pipe applying nuclear techniques used by these tools of registrations to derive the water saturation and of hydrocarbon. In this work the basic principles of radioactivity and their application in the radioactive tools are described as well as the operative aspects of the tools before mentioned, some practical applications of the saturation control tool are presented and a technical study of cost-benefit and it is shown as the technology advances have allowed to carry out considerable progresses in the taking of information of the mature wells helping by this way, to build better geological models in the locations that help to increase the hydrocarbon production in wells that have many years of exploitation. (Author)

  14. 2-(2-phenylethyl)chromone derivatives from Chinese agarwood induced by artificial holing.

    Science.gov (United States)

    Li, Wei; Cai, Cai-Hong; Dong, Wen-Hua; Guo, Zhi-Kai; Wang, Hao; Mei, Wen-Li; Dai, Hao-Fu

    2014-10-01

    Three new 2-(2-phenylethyl)chromone derivatives (1-3), together with thirteen known ones (4-16), were isolated from the EtOAc extract of Chinese agarwood induced by artificial holing, originating from Aquilaria sinensis (Lour.) Gilg (Thymelaeaceae). The chemical structures of the new compounds were identified by spectroscopic techniques (UV, IR, MS, 1D and 2D NMR). Compounds 1, 6, 15 and 16 exhibited inhibitory effects on Staphylococcus aureus, and compounds 15 and 16 showed inhibitory effects on Ralstonia solanacearum. Compounds 1-3, 7, 9, 11, 12, 15 and 16 exhibited acetylcholinesterase inhibitory activity. A possible biogenetic pathway of compounds 1-16 was proposed to show the relationships between diepoxy-tetrahydro-2-(2-phenylethyl)chromones, epoxy-tetrahydro-2-(2-phenylethyl) chromones, tetrahydro-2-(2-phenylethyl)chromones, and 2-(2-phenylethyl)chromones of the flidersia type, the four main types of 2-(2-phenylethyl)chromones found in agarwood, on the basis of their appearances in different stage of agarwood formation. PMID:25068202

  15. Radioactive Ion Beam Production by Fast-Neutron-Induced Fission in Actinide Targets at EURISOL

    CERN Document Server

    Herrera-Martínez, Adonai

    The European Isotope Separation On-Line Radioactive Ion Beam Facility (EURISOL) is set to be the 'next-generation' European Isotope Separation On-Line (ISOL) Radioactive Ion Beam (RIB) facility. It will extend and amplify current research on nuclear physics, nuclear astrophysics and fundamental interactions beyond the year 2010. In EURISOL, the production of high-intensity RIBs of specific neutron-rich isotopes is obtained by inducing fission in large-mass actinide targets. In our contribution, the use of uranium targets is shown to be advantageous to other materials, such as thorium. Therefore, in order to produce fissions in U-238 and reduce the plutonium inventory, a fast neutron energy spectrum is necessary. The large beam power required to achieve these RIB levels requires the use of a liquid proton-to-neutron converter. This article details the design parameters of the converter, with special attention to the coupled neutronics of the liquid converter and fission target. Calculations performed with the ...

  16. Radiological considerations on multi-MW targets Part I Induced radioactivity

    CERN Document Server

    Agosteo, S; Silari, M; 10.1016/j.nima.2005.02.018

    2005-01-01

    CERN is designing a Superconducting Proton Linac (SPL) to provide a 2.2GeV, 4MW proton beam to feed facilities like, for example, a future Neutrino Factory or a Neutrino SuperBeam. The material activation in such facilities is an important aspect that has to be taken into account at an early design stage. In particular, the choice of the target has consequences on the induced radioactivity and dose rates in the target itself and in its surroundings. In the present work, the radiological aspects of a stationary target made up of small tantalum pellets are compared to those of a free-surface jet of mercury. An estimation of the hadronic inelastic interactions and the production of residual nuclei in the target, the magnetic horn, the decay tunnel, the surrounding rock and a downstream dump were performed for both targets by the Monte Carlo hadronic cascade code FLUKA. The aim was to assess the dose equivalent rate to be expected during maintenance work and to evaluate the amount of residual radioactivity, which...

  17. Assessing the Effectiveness of Risk Communication for Maintenance Workers Who Deal With Induced Radioactivity Management of Medical Linear Accelerators.

    Science.gov (United States)

    Watanabe, Hiroshi; Maehara, Yoshiaki; Fujibuchi, Toshioh; Koizumi, Mitsue; Yamaguchi, Ichiro; Kida, Tetsuo; Ooyama, Masaya; Horitsugi, Genki; Hiraki, Hitoshi; Tsukamoto, Atsuko; Itami, Jyun

    2015-08-01

    In Japan, an amended law that mandates levels of unintended induced radioactivity has been in effect since 1 April 2012. According to the new regulation, if the concentration of induced radioactivity in affected parts is above the clearance level, the parts must be regarded as radioactive even if they weigh less than 1 kg. This regulation reform raises several new issues concerning medical linear accelerators, including how to determine the decay period for induced radioactivity before maintenance can be performed and how to identify what parts should be considered radioactive waste. The authors performed several risk communication (RC) activities aimed at improving the understanding of maintenance workers at medical accelerator manufacturers and establishing good guidelines by involving stakeholders. For this purpose, a working group was established and conducted RC activities, such as holding opinion exchange meetings between medical staff and maintenance workers and creating a booklet to answer questions from maintenance workers. To evaluate these activities, three questionnaire surveys were conducted between 2011 and 2014. According to the results of this study, the ratio of maintenance workers who accepted "The decay period is within one week" was approximately 60% at the third survey and significantly increased (P < 0.0001) during the survey period. Approximately 25% of the maintenance workers felt that not enough information was provided about the decay period, and approximately 63% thought that the information provided on the health effects of radiation was sufficient. These results suggest that the present RC was successful. PMID:26107435

  18. The photosynthetic bacterial reaction center in native and artificial envirnoments: effects on light-induced electron transfer

    OpenAIRE

    Dezi, Manuela

    2008-01-01

    In this thesis we focussed on the characterization of the reaction center (RC) protein purified from the photosynthetic bacterium Rhodobacter sphaeroides. In particular, we discussed the effects of native and artificial environment on the light-induced electron transfer processes. The native environment consist of the inner antenna LH1 complex that copurifies with the RC forming the so called core complex, and the lipid phase tightly associated with it. In parallel, we analyzed th...

  19. Detection of pion-induced radioactivity by autoradiography and positron emission tomography (PET)

    International Nuclear Information System (INIS)

    An autoradiographic technique incorporating a new imaging system was used to detect pion-induced radioactivity in Plexiglass and the results were compared with aluminium activation and PET imaging. The activity distribution in the region of the pion-stopping peak was similar in all three cases. Another large signal in the entrance region due to in-flight interactions [12C(?-,?-n)11C] was detected by autoradiography and by PET but was not reflected in the aluminium activation measurements. This new technique is capable of defining the stopping region in phantoms with a better resolution than PET scanning and is useful as a complementary technique to other methods of pion dosimetry

  20. Background studies: human-induced effects on the evolution of shallow land burial sites for radioactive waste disposal

    International Nuclear Information System (INIS)

    This report presents the results of a programme of background research on the human-induced effects on the long term evolution of shallow disposal sites for low level radioactive wastes. The work is intended to support development and use of the TIME2 simulation code. Within the context of climatic change up to the next glacial maximum three areas are addressed: planning and legislative control over site usage, biosphere state changes and intrusion. An appendix presents a discussion of some planning aspects of radioactive waste disposal. (author)

  1. A study of the stability of an artificial beach and of the transport of fine sediments in suspension using radioactive tracers

    International Nuclear Information System (INIS)

    The paper describes two applications of radioactive tracers in dynamic sedimentology in the light of experiments carried out in Singapore, between 1981 and 1982, along the new beaches reclaimed from the sea. The first part deals with the properties of transfer of a silt sediment suspension by the west tide. The tracer used was 198Au-labelled silt. Successive determinations were made of the trajectory, average velocity, variation in time of the vertical and horizontal dispersion, and dilution and settling of sediments released into the sea by point and instantaneous injection, after which the data were extrapolated to continuous release. The second part is devoted to a study of the stability of the artificial beaches forming the new coastline, using for the purpose 192Ir-labelled glass tracer of the same grain size as the sediments in situ. The results are presented in the form of isoactivity curves and transport diagrams. They can be used to determine the axis and average velocity of transport and the dispersion parameters (dimensions of the patch, change in the centre of gravity and quartiles). The thickness and rate of bed-load transport are then calculated by the 'method of count-rate balance'. Each part has a section on 'methodology', in which the tracer technique is reviewed (principle, labelling, release and detection) and a section where the results are analysed. The study has shown the hazards of beach pollution and the silting-up of harbour installations through the discharge of sediments into the sea as well as the hazard of erosion at the edges of the new coastline by the north-east and south-west monsoons. (author)

  2. Does ozone enhance the remineralizing potential of nanohydroxyapatite on artificially demineralized enamel? A laser induced fluorescence study

    Science.gov (United States)

    Srinivasan, Samuelraj; Prabhu, Vijendra; Chandra, Subhash; Koshy, Shalini; Acharya, Shashidhar; Mahato, Krishna K.

    2014-02-01

    The present era of minimal invasive dentistry emphasizes the early detection and remineralization of initial enamel caries. Ozone has been shown to reverse the initial demineralization before the integrity of the enamel surface is lost. Nano-hydroxyapatite is a proven remineralizing agent for early enamel caries. In the present study, the effect of ozone in enhancing the remineralizing potential of nano-hydroxyapatite on artificially demineralized enamel was investigated using laser induced fluorescence. Thirty five sound human premolars were collected from healthy subjects undergoing orthodontic treatment. Fluorescence was recorded by exciting the mesial surfaces using 325 nm He-Cd laser with 2 mW power. Tooth specimens were subjected to demineralization to create initial enamel caries. Following which the specimens were divided into three groups, i.e ozone (ozonated water for 2 min), without ozone and artificial saliva. Remineralization regimen was followed for 3 weeks. The fluorescence spectra of the specimens were recorded from all the three experimental groups at baseline, after demineralization and remineralization. The average spectrum for each experimental group was used for statistical analysis. Fluorescence intensities of Ozone treated specimens following remineralization were higher than that of artificial saliva, and this difference was found to be statistically significant (Penamel. Ozone can be considered an effective agent in reversing the initial enamel caries there by preventing the tooth from entering into the repetitive restorative cycle.

  3. Characteristics of radioactivities induced in aluminum alloys and the effects due to those major and minor components

    International Nuclear Information System (INIS)

    In order to search the usefulness of aluminum alloys as a material for an accelerator and its surrounding apparatus, the characteristics of radioactivities induced in several aluminum alloys (AA 1230, AA 2219, JIS 5052, AA 6063 and AA 7079) and stainless steel (SUS 304) irradiated for a long time with high energy bremsstrahlung have been studied fundamentally and compared with each other. After the concentrations of major alloying elements and impurities in the above samples were determined by means of photon-activation, proton-activation and emission spectrochemical analyses, they were irradiated with 30 and 200 MeV bremsstrahlung. As the results, it was proved that the intensities of radioactivities induced in the aluminum alloys are greatly affected by those major and minor components, but are remarkably lower than that in the stainless steel. (author)

  4. Evaluation of potential induced radioactivity in medical products as a function of electron energy in electron beam sterilization

    International Nuclear Information System (INIS)

    Commercial sterilization of medical devices may be performed using electron beam irradiators at various electron energies. The potential for activating components of the devices has been discussed, with current standards stating that electron energy greater than 10 MeV requires assessment of potential induced radioactivity. This paper evaluates the potential for induced activity in medical products sterilized in electron beam as a function of the electron maximum energy. Monte Carlo simulation of a surrogate medical device was used to calculate photon and neutron fields resulting from electron irradiation, which were used to calculate concentrations for several radionuclides. The experiments confirmed that 10 MeV is a conservative assumption for limiting induced radioactivity. However, under the conditions as evaluated, which is a limited total quantity of metal in the material being irradiated and absent a limited number of elements; the amount of induced activity at 12 MeV could also be considered insignificant. The comparison of the sum-of-fractions to the US Nuclear Regulatory Commission exempt concentration limits is less than unity for all energies below 12.1 MeV, which suggests that there is minimal probability of significant induced activity at energies above the 10 MeV upper energy limit. - Highlights: ? This study estimates induced radioactivity for electron irradiation as a function of energy. ? MCNPX was used to model systems from 8 MeV up to 13 MeV. ? Under conditions given, energies up to 12 MeV may create insignificant activation. ? Measured concentrations were within a factor of two of those calculated. ? Depth dose profiles show good agreement with the model.

  5. Gyroharmonic Features of Generation of Artificial Irregularities Hf-Induced in the Ionospheric F_2 Region

    Science.gov (United States)

    Frolov, Vladimir; Akchurin, Adel; Bolotin, Ilya; Zykov, Evgeniy; Vertogradov, Gennadiy

    In the report, basing on experimental data obtained at the SURA heating facility [1-4], we consider gyroharmonic features of generation of artificial irregularities HF-induced in the ionospheric F _{2} region. In [5] it was revealed that, when the pump wave frequency (f _{PW}) is slightly above the 4th electron gyro harmonic frequency (4f_{ce}) in the ionosphere disturbed volume, spectra of signals field-aligned scattered from irregularities with l_? ? 10 - 20 m had widths up to DeltaF ? 10 Hz in comparison with DeltaF ? 0.5 Hz, when the f _{PW} was below 4f_{ce}. Obtained in our experiments data have shown that the scattering from decameter irregularities consists of two components (narrow- and wideband) distinguished by their spectral characteristics, relaxation times, and dependence on f _{PW}. The narrowband component is related to scattered signals when f _{PW} is outside the gyro harmonic frequency range. The wideband component is observed at deltaf = f_{PW} - 4f_{ce} ? 0 - 150 kHz and shows well-pronounced gyro features; it has the maximum width (up to 10 Hz) at deltaf_{m} ? 20 - 60 kHz, where the BUM component in SEE spectra has the greatest intensity. A typical growth time for the wideband component is of the same order of magnitude as the growth time of decameter irregularities (0.3 - 0.5 s); its typical decay time is of about 0.4 - 0.9 s, which is much shorter of the decay time for decameter irregularities. It is significant that at the decay stage the fast narrowing of the wideband component spectra is observed. In [4] it was observed short-term decreases in TEC of about 0.03 - 0.05 TECU when a sounding wave crossed the magnetic zenith region in the ionosphere disturbed volume. According to [6] such TEC variations can be produced by generation of super small-scale striations with l_? ? 10 - 20 sm. Basing on obtained experimental data it may be concluded that not only the generation of small-scale irregularities with l_? Quant. Electron., Engl. Transl., 2000. V. 43(6), p. 446. 2. Kagan, L.M., et al. // J. Radiophysics and Radio Astronomy, 11(3), 221-242, 2006. 3. Frolov V.L., et al. // Radiophys. Quant. Electron., Engl. Transl., 2008. Vol. 51(5), p. 367. 4. Frolov V.L., et al. // Radiophys. Quant. Electron., Engl. Transl., 2012. Vol.55(6), p. 357. 5. Ponomarenko et al. // J. Geophys. Res., 1999. Vol. 104, No. A5, p. 10,081. 6. Gurevich and Zybin. // Phys. Lett. A. 2006. Vol. 358, p.159.

  6. EAGLE GUIDE. Radioactivity from A to Z

    International Nuclear Information System (INIS)

    The booklet on radioactivity is a lexicon-type compendium of definitions, fundamental terms and information on radioactivity. Radioactive processes occur in the sun and on earth, live is dependent on these processes. Human beings are exposed to cosmic radiation, radiation from natural radioactive nuclides and artificial radiation sources. There is almost no possibility to protect oneself from natural radioactivity. The protection from artificial radioactivity can be reached by appropriate protection measures. Artificial radiation sources will certainly by part of mankind in the future, in nuclear medicine, radiation therapy and for research purposes. The booklet is aimed to provide information to everybody as a basis to be able to discuss the respective topics.

  7. Natural radioactivity contents in tobacco and radiation dose induced from smoking

    International Nuclear Information System (INIS)

    One of the causative factors for cancer-inducing mechanisms in humans is radioactive elements present in tobacco leaves used in the manufacture of cigarettes. Smoking of tobacco and its products increases the internal intake and radiation dose due to naturally occurring radionuclides that are considered to be one of the most significant causes of lung cancer. In this work, different commercial types of cigarettes, cigar and moassel were collected from market. Naturally occurring radionuclides 226Ra and 214Bi (238U series), 228Ac and 228Ra (232Th series), 40K and man-made 137Cs were measured in tobacco using gamma-ray spectrometer. Results show that the average concentrations of 238U, 232Th and 40K were 4.564, 3.940 and 1289.53 Bq kg-1, respectively. This reflects their origin from the soil by root uptake and fertilisers used in the cultivation of tobacco plants. Concentration of 137Cs was 0.348 Bq kg-1 due to root uptake or deposition onto the leaf foliage. For smokers, the annual effective dose due to inhalation of 238U varied from 49.35 to 139.40 ?Sv-1 (average 104.27 ?Sv y-1), while of 232Th from 23.86 to 111.06 ?Sv y -1 (average 65.52 ?Sv y-1). The annual effective dose resulting from 137Cs was varied from 10.96 to 24.01 nSv y-1 (average 19.41 nSv y-1). (authors)

  8. Analysis of micro-composition of biological tissue by means of induced radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Tobias, C.A.; Dunn, R.W.

    1948-05-24

    The use of radioactive isotopes as tracers promises a wealth of information regarding the biochemical role of most elements and their components. Usually a radioactive sample of the element to be studied is administered to the plant or animal in a convenient form, and its distribution and rate of exchange are determined in later assays. This technique has, however, certain limitations, two of which will be discussed here: (1) radioactive isotopes are not generally useful for measurements of the concentration of elements in the body or its parts. They can be used only to give a measure of the rate of exchange of the elements and (2) the use of radioactive isotopes for tracer experiments requires that the radiation dose delivered to the tissue should be small in order not to disturb normal biological function.

  9. Studying the features of transport processes in the upper ionosphere by means of HF-induced artificial ionosphere turbulence

    Science.gov (United States)

    Frolov, V.; Sergeev, E.

    We analyze some possibilities of experimental determination of the velocity at which the artificial plasma disturbances, induced in the regions of resonance interactions between a HF powerful wave and the F-region ionospheric plasma, spreads along a geomagnetic field line. The diagnostics of these disturbances is based on the used of the stimulated electromagnetic emission (SEE) HF-induced in the ionosphere disturbed volume. The experimental results discussed here were obtained in measurements at the Sura heating facility (Nizhnii Novgorod, Russia) in 1996 - 2003 employing the so-called additional pumping scheme. In such a scheme radiation of one from three module of the Sura facility is used as a diagnostic wave inducing diagnostic SEE (DSEE). Variations in characteristics of the DSEE are a result of influence of turbulence induced by the second powerful wave (pump wave, PW), which is radiated at another frequency and used here as an external source of plasma disturbances. Thus, two spaced disturbed volumes are formed in the ionosphere F-region. The temporal delay between the appearance of PW-produced disturbances at DSEE generation level and the time of switching on the PW allows to estimate their spread velocity along geomagnetic field lines. Results of the performed measurements have unambiguously shown that the spread velocity was usually higher than the ion thermal velocity (VTi ? 10^5 cm/s under conditions of measurements). In many cases, this velocity was close to and sometimes even much higher than the electron thermal velocity VTe ? 2\\cdot10^7 cm/s. It is important to note that pumping during a time interval of 50 - 100 ms at the effective radiated power of about of 50 MW is sufficient to produce visible changes in DSEE intensity. Taking into account the experimental data obtained, it can be assumed that we deal here with field-aligned flows of thermal and suprathermal electron HF-induced in the ionosphere disturbed volume. These electron flows, due to short-circuit currents induced simultaneously, can stimulate the appearance of secondary ionosphere disturbances in a region whose size is much larger than the resonance interaction region. Generation of artificial irregularities in such a large ionosphere region has been recently confirmed in satellite tomography experiments performed at the Sura facility in August 2002. The work was supported by RFBR Grant %No. 02-02-17475 and CRDF Grant %No. RPO-1334.

  10. Studies of ionising radiation induced bystander effects in 3D artificial tissue system and applications for radiation protection

    International Nuclear Information System (INIS)

    The universality of the target theory of radiation-induced effects is challenged by observations on non-targeted effects such as bystander effects. Essential features of non-targeted effects are that they do not require direct nuclear exposure by radiation and they are particularly significant at low doses. This new evidence suggests a need for a new paradigm in radiation biology. The new paradigm should cover both the classical (targeted) and the non-targeted effects. The bystander effect cannot be comprehensively explained on the basis of a single cell reaction. It is well known that an organism is composed of different cell types that interact as functional units in a way to maintain normal tissue function. Therefore the radiation response is not simply the sum of cellular responses as assumed in classical radiobiology, predominantly from studies using cell cultures. Experimental models, which maintain tissue-like intercellular cell signalling and 3D structure, are essential for proper understanding of the bystander effect. Our work relates to experimentation with novel 3D artificial human tissue systems available from MatTek Corporation (Boston, USA). Air-liquid interface culture technique is used to grow artificial tissues, which allow to model conditions present in vivo. The Gray Cancer Institute (Northwood, UK) charged particle microbeam was used to irradiate tissue samples in a known pattern with a known number of 3He2+ particles or protons. After irradiation, the tissues models were incubated for 3 days, fixed in 10 % NBF, paraffin embedded and then sliced into 5 ?m histological sections located at varying distances from the plane of the irradiated cells. We studied in situ apoptosis and markers of differentiation. Significantly elevated bystander induced apoptosis was observed with 3'-OH DNA end-labelling based technique in 3D artificial tissue systems. Our results also suggested an importance of proliferation and differentiation status for bystander effect induction. A single 2 ?m location on tissue section was pre-irradiated with 1-10 3He2+ particles (5 MeV; LET 75 keV/?m) using microbeam system. Even although only a single region of the tissue section was targeted, thousands of additional cells were found to undergo bystander induced differentiation. This resulted in an overall increase in the fraction of differentiated cells for approximately 10-15 %, which are much greater than that observed for the induction of damage (not more than 1-2 % of apoptotic cells). Our theory is that the main functions of bystander effect are to decrease the risk of transformation in a multi cultural organism exposed to radiation by removing a group of potentially damaged cells via apoptosis and increased differentiation. (author)

  11. Virus activated artificial ECM induces the osteoblastic differentiation of mesenchymal stem cells without osteogenic supplements

    OpenAIRE

    Wang, Jianglin; Wang, Lin; Li, Xin(Institute of High Energy Physics, Chinese Academy of Sciences, 100049, Beijing, China); Mao, Chuanbin

    2013-01-01

    Biochemical and topographical features of an artificial extracellular matrix (aECM) can direct stem cell fate. However, it is difficult to vary only the biochemical cues without changing nanotopography to study their unique role. We took advantage of two unique features of M13 phage, a non-toxic nanofiber-like virus, to generate a virus-activated aECM with constant ordered ridge/groove nanotopography but displaying different fibronectin-derived peptides (RGD, its synergy site PHSRN, and a com...

  12. Snag characteristics and dynamics following natural and artificially induced mortality in a managed loblolly pine forest.

    Energy Technology Data Exchange (ETDEWEB)

    Zarnoch, Stanley J. [USDA Forest Service; Vukovich, Mark A. [USDA Forest Service; Kilgo, John C. [USDA Forest Service; Blake, John I. [USDA Forest Service

    2013-06-10

    A 14-year study of snag characteristics was established in 41- to 44-year old loblolly pine (Pinus taeda L.) stands in southeastern USA. During the initial 5.5 years, no stand manipulation or unusually high-mortality events occurred. Afterwards, three treatments were applied consisting of trees thinned and removed, trees felled and not removed, and artificial creation of snags produced by girdling and herbicide injection. The thinned treatments were designed to maintain the same live canopy density as the snag-created treatment, disregarding snags that remained standing.We monitored snag height, diameter, density, volume, and bark percentage; the number of cavities was monitored in natural snags only. During the first 5.5 years, recruitment and loss rates were stable, resulting in a stable snag population. Large snags (?25 cm diameter) were common, but subcanopy small snags (10 to <25 cm diameter) dominated numerically. Large natural snags survived (90% quantile) significantly longer (6.0–9.4 years) than smaller snags (4.4–6.9 years). Large artificial snags persisted the longest (11.8 years). Cavities in natural snags developed within 3 years following tree death. The mean number of cavities per snag was five times greater in large versus small snags and large snags were more likely to have multiple cavities, emphasizing the importance of mature pine stands for cavity-dependent wildlife species.

  13. Reaction dynamics induced by the radioactive ion beam 7Be on medium-mass and heavy targets

    Science.gov (United States)

    Mazzocco, M.; Boiano, A.; Boiano, C.; La Commara, M.; Manea, C.; Parascandolo, C.; Pierroutsakou, D.; Stefanini, C.; Strano, E.; Torresi, D.; Acosta, L.; Di Meo, P.; Fernandez-Garcia, J. P.; Glodariu, T.; Grebosz, J.; Guglielmetti, A.; Keeley, N.; Lay, J. A.; Marquinez-Duran, G.; Martel, I.; Mazzocchi, C.; Molini, P.; Nicoletto, M.; Pakou, A.; Parkar, V. V.; Rusek, K.; Sánchez-Benítez, A. M.; Sandoli, M.; Sava, T.; Sgouros, O.; Signorini, C.; Silvestri, R.; Soramel, F.; Soukeras, V.; Stiliaris, E.; Stroe, L.; Toniolo, N.; Zerva, K.

    2015-10-01

    We studied the reaction dynamics induced at Coulomb barrier energies by the weakly-bound Radioactive Ion Beam 7Be (S? = 1.586 MeV) on medium-mass (58Ni) and heavy (208Pb) targets. The experiments were performed at INFN-LNL (Italy), where a 2-3×105 pps 7Be secondary beam was produced with the RIB in-flight facility EXOTIC. Charged reaction products were detected by means of high-granularity silicon detectors in rather wide angular ranges. The contribution presents an up-to-date status of the data analysis and theoretical interpretation for both systems.

  14. Measurement of the residual radioactivity induced in the front foil of a target assembly in a modern medical cyclotron.

    Science.gov (United States)

    O'Donnell, R G; León Vintró, L; Duffy, G J; Mitchell, P I

    2004-01-01

    The levels of residual radioactivity induced in Havar foils at the entrance of a high-pressure 18O-enriched water target used for the production of 18F- in a medical cyclotron with 16 MeV protons have been determined using high-resolution gamma-ray spectrometry. Whole body and skin dose rates arising from exposure to these foils during their periodic replacement have been estimated. The results indicate that irradiated foils do not represent a significant radiological hazard for the cyclotron operating staff and that no waste disposal difficulties should be encountered after an appropriate 'cooling' period of 2 years. PMID:14987699

  15. Measurement of the residual radioactivity induced in the front foil of a target assembly in a modern medical cyclotron

    International Nuclear Information System (INIS)

    The levels of residual radioactivity induced in Havar[reg) foils at the entrance of a high-pressure 18O-enriched water target used for the production of 18F- in a medical cyclotron with 16 MeV protons have been determined using high-resolution ?-ray spectrometry. Whole body and skin dose rates arising from exposure to these foils during their periodic replacement have been estimated. The results indicate that irradiated foils do not represent a significant radiological hazard for the cyclotron operating staff and that no waste disposal difficulties should be encountered after an appropriate 'cooling' period of 2 years

  16. Modulated photoacoustic spectroscopy study of an artificial tanning on human skin induced by dihydroxyacetone.

    Science.gov (United States)

    Benamar, N; Laplante, A F; Lahjomri, F; Leblanc, R M

    2004-10-01

    A modulated photoacoustic spectroscopy study on the effect of dihydroxyacetone, commonly used for artificial tan, is presented. The study was carried out in the presence and absence of dimethylisosorbide (a solvent for dihydroxyacetone) on fresh human skin, obtained from the breast region of recent autopsy cases (two females), at a frequency of 25 Hz, which enabled us to study the effect at a depth of 30 microm in the stratum corneum and beneath. By monitoring the photoacoustic signal intensity with time in the region of 300-400 nm, which is a specific region for melanin pigment, it is demonstrated that dihydroxyacetone in combination with dimethylisosorbide enhances the process of tanning. Dihydroxyacetone also has an effect on the amino acids and nucleic acids which is bad for the skin. PMID:15535185

  17. Induced radioactivity in Cu targets produced by high-energy heavy ions and the corresponding estimated photon dose rates

    International Nuclear Information System (INIS)

    Irradiation experiments were performed at the Heavy Ion Medical Accelerator in Chiba (HIMAC) facility, National Inst. of Radiological Sciences. The radioactive spallation products in a thick Cu target were obtained for Ar(230, 400 MeV per nucleon), Si(800 MeV per nucleon), Ne(100, 230, 400 MeV per nucleon), C(100, 230, 400 MeV per nucleon), He(100, 230 MeV per nucleon), p(100, 230 MeV) ions. The gamma-ray spectra from irradiated Cu samples inserted into the composite Cu target were measured with a high-purity germanium (HPGe) detector. From the gamma-ray spectra, we obtained the spatial distribution of radioactive yields of spallation products of 40 nuclides in the Cu sample in the Cu target. From the spatial distribution of radioactive yields, we estimated the residual activity and photon dose induced in the Cu target. The residual activity and photon dose become larger with the increase in projectile energy per nucleon and the range of the projectile beam for the same projectile energy per nucleon. (authors)

  18. Dynamics of presynaptic protein recruitment induced by local presentation of artificial adhesive contacts

    OpenAIRE

    Suarez, Fernando; Thostrup, Peter; Colman, David; Grutter, Peter

    2012-01-01

    Here we introduce a novel approach to induce and observe the formation of presynaptic compartments in axons through a combination of Atomic Force Microscopy (AFM) and fluorescence microscopy. First, we use a poly-D-lysine coated bead attached to an AFM tip to induce the recruitment of two synaptic proteins, bassoon and synaptophysin, and measure their absolute arrival times to the presynaptic department. We find that bassoon arrives before synaptophysin. Second, we observed the formation of v...

  19. Measurements and analyses of decay radioactivity induced in simulated deuterium-tritium neutron environments for fusion reactor structural materials

    International Nuclear Information System (INIS)

    To meet urgent requirements for data validation, an experimental analysis has been carried out for isotopic radioactivity induced by deuterium-tritium neutron irradiation in structural materials. The primary objective is to examine the adequacy of the activation cross sections implemented in the current activation calculation codes considered for use in fusion reactor nuclear design. Four activation cross-section libraries, namely, JENDL, LIB90, REAC*63, and REAC*175 were investigated in this current analysis. The isotopic induced radioactivity calculations using these four libraries are compared with experimental values obtained in the Japan Atomic Energy Research Institute/U.S. Department of Energy collaborative program on fusion blanket neutronics. The nine materials studied are aluminum, silicon, titanium, vanadium, chromium, MnCu alloy, iron, nickel, niobium, and Type 316 stainless steel. The adequacy of the cross sections is investigated through the calculation to experiment analysis. As a result, most of the discrepancies in the calculations from experiments can be explained by inadequate activation cross sections. In addition, uncertainties due to neutron energy groups and neutron transport calculation are considered. The JENDL library gives the best agreement with experiments, followed by REAC*175, LIB90, and REAC*63, in this order. 45 refs., 32 figs., 5 tabs

  20. Force induced and electron stimulated STM manipulations: routes to artificial nanostructures as well as to molecular contacts, engines and switches

    International Nuclear Information System (INIS)

    Initially invented to image surfaces down to atomic scale, the scanning tunneling microscope (STM) has been further developed in the last few years to an operative tool, with which atoms and molecules can be manipulated at low substrate temperatures at will with atomic precision in different manners by using solely the tip-adparticle forces. In this way various artificial structures on nanoscale have been created and in situ characterized with the STM. Such structures as well as single molecules can be investigated by scanning tunnelling spectroscopy (STS) both with respect to their local electronic and even vibrational properties. Modifications of single molecules can be induced by using the tunnelling electron current: Rotations, diffusional jumps, vibrational excitations, desorption, dissociation and even association can be induced in individual molecules, often in a rather precise way by tuning the voltage into the energy levels of specific vibrations or electronic levels. These possibilities give rise to startling new opportunities for physical and chemical experiments on the single atom and single molecule level. Here a brief overview on results obtained with these new techniques is given

  1. Experimentally induced gluten enteropathy in artificially fed neonatal rats. Protective effect of epidermal growth factor (EGF).

    Czech Academy of Sciences Publication Activity Database

    Št?pánková, Renata; Kofro?ová, Olga; Tu?ková, Ludmila; Kozáková, Hana; Tlaskalová, Helena

    Pa?íž, 2002. s. 51. [International Symposium On Coeliac Disease /10./. 02.06.2002-05.06.2002, Pa?íž] R&D Projects: GA ?R GA303/00/1370 Grant ostatní: OLGI1999-000(FR) 50 Keywords : induced gluten * epidermal * growth factor Subject RIV: EE - Microbiology, Virology

  2. The electrical charging of inactive aerosols in high ionised atmosphere, the electrical charging of artificial beta radioactive aerosols; Le processus de charge electrique: des aerosols non radioactifs en milieu fortement ionise, des aerosols radioactifs artificiels emetteurs beta

    Energy Technology Data Exchange (ETDEWEB)

    Gensdarmes, F

    2000-07-01

    The electrical properties of aerosols greatly influence their transport and deposition in a containment. In a bipolar ionic atmosphere, a neutral electric charge on aerosols is commonly assumed. However, many studies report a different charge distribution in some situations, like highly ionised atmosphere or in the case of radioactive aerosols. Such situations could arise from a hypothetical accident in a nuclear power plant. Within the framework of safety studies which are carried out at IPSN, our aims were the study of electrical properties of aerosols in highly ionised atmosphere, and the study of artificial radioactive aerosols, in order to suggest experimental validation of available theories. For this purpose, we designed an experimental device that allows us to measure non-radioactive aerosol charge distribution under high gamma irradiation, up to 10{sup 4} Gy/h. With our experimental device we also studied the properties of small ions in the medium. Our results show a variation of the charge distribution in highly ionised atmosphere. The charge increases with the dose of gamma ray. We have related this variation with the one of the small ions in the gases, according to theoretical prediction. However, the model overestimates slightly our experimental results. In the case of the radioactive aerosols, we have designed an original experimental device, which allows us to study the charge distribution of a {sup 137}Cs aerosol. Our results show that the electric charging of such aerosols is strongly dependent on evolution parameters in a containment. So, our results underline a great enhancement of self-charging of particles which are sampled in a confined medium. Our results are qualitatively in agreement with the theoretical model; nevertheless the latter underestimates appreciably the self-charging, owing to the fact that wall effects are not taken into account. (author)

  3. Alloy development for fast induced radioactivity decay for fusion reactor applications

    International Nuclear Information System (INIS)

    The Cr-Mo ferritic (martensitic) steels and austenitic stainless steels (primarily type 316 and variations on that composition) are the leading candidates for the structural components for future fusion reactors. However, irradiation of such steels in a fusion environment produces long-lived radioactive isotopes. These isotopes lead to difficult radioactive waste disposal problems once the structure is removed from service. Such problems could be reduced by developing steels that contain only elements that produce radioactive isotopes that decay to low levels in a reasonable time (tens of years instead of hundreds or thousands of years). This report discusses the development of such steels by making elemental substitutions in the steels now under consideration. Molybdenum must be replaced in the Cr-Mo steels; nickel and molybdenum both must be replaced in the austenitic stainless steels (the nitrogen concentration must be limited, and niobium, maintained to extremely low levels). Appropriate substitutions are tungsten for molybdenum in the Cr-Mo steels and manganese for nickel in the austenitic stainless steels. Indications are that suitable ferritic steels can be developed, but development of a nickel-free austenitic stainless steel with properties similar to the Cr-Ni stainless steels appears to be much more complex

  4. Dynamics of presynaptic protein recruitment induced by local presentation of artificial adhesive contacts.

    Science.gov (United States)

    Suarez, Fernando; Thostrup, Peter; Colman, David; Grutter, Peter

    2013-01-01

    In this study, we introduce a novel approach to induce and observe the formation of presynaptic compartments in axons through a combination of atomic force microscopy (AFM) and fluorescence microscopy. First, we use a poly-D-lysine-coated bead attached to an AFM tip to induce the recruitment of two synaptic proteins, bassoon and synaptophysin, and measure their absolute arrival times to the presynaptic department. We find that bassoon arrives before synaptophysin. Second, we observe the formation of very long (several 10s of ?m), structured, protein-containing membranous strings as the AFM tip was withdrawn from the axon. It is conceivable that these strings might be a novel mechanism by which new neurites or branch points along existing neurites may be generated in situ. PMID:22648784

  5. Artificially induced polyploidization in Humulus lupulus L. and its effect on morphological and chemical traits

    OpenAIRE

    Trojak-Goluch, Anna; Skomra, Urszula

    2013-01-01

    Chemically induced polyploids were obtained by the colchicine treatment of shoot tips of Humulus lupulus L. ‘Sybilla’. Flow cytometry revealed that most of the treatments resulted in the production of tetraploids. The highest number of tetraploids was obtained when explants were immersed in 0.05% colchicine for 48 h. A field experiment was conducted to compare diploid and tetraploid plants and assess the effect of genome polyploidization on the morphological and chemical characteristics. Tetr...

  6. Probing the connection of PBSs to the photosystems in Spirulina platensis by artificially induced fluorescence fluctuations

    International Nuclear Information System (INIS)

    The molecular architecture and the structural connections of phycobilisomes (PBSs) to the photosystems in the intact cells of Spirulina platensis were studied by taking advantage of glycerol- and betaine-induced fluorescence fluctuations. Generally, with a selective excitation of C-phycocyanin (C-PC), glycerol could induce not only decoupling of PBSs from the photosystems but also of C-PC rods from allophycocyanin (APC) cores, while betaine could strengthen the connection of PBSs to the thylakoid membrane but induce a partial dissociation of PBS. On the other hand, glycerol did not exert an influence on the fluorescence spectra of the photosystems in isolated thylakoid membrane. Therefore, it was deduced that glycerol could provide a molecular environment to weaken the hydrophobic interactions of not only the LCM with the membrane but also the linker polypeptides to the water-soluble phycobiliproteins (C-PC and APC), while the betaine could strengthen the hydrophobic interaction of LCM with the membrane but weaken the electrostatic interaction of linker polypeptides to C-PC and/or APC

  7. HYPOTHALAMIC OREXINE SYSTEM ACCELERATES REGULATION OF SLEEP HOMEOSTASIS AND SLEEP-WAKEFULNESS CYCLE RECOVERY FROM BARBITURATE ANESTHESIA-INDUCED ARTIFICIAL SLEEP.

    Science.gov (United States)

    Nachkebia, N; Maglakelidze, N; Chijavadze, E; Chkhartishvili, E; Babilodze, M

    2015-12-01

    The work was aimed for the ascertainment of following question - whether Orexin-containing neurons of dorsal and lateral hypothalamus and brain Orexinergic system in general are those cellular targets which can accelerate recovery of disturbed sleep homeostasis and restoration of sleep-wakefulness cycle behavioral states from barbiturate anesthesia-induced artificial sleep. Investigation was carried out on 18 wild type white rats (weight 200-250gr). Different doses of Nembutal Sodium were used for the initiation of deep anesthesia. 30 min after barbiturate anesthesia induced artificial sleep serial electrical stimulations of dorsal or lateral hypothalamus were started. Stimulation period lasted for 1 hour with the 5 min intervals between subsequent stimulations applied by turn to the left and right side hypothalamic parts. EEG registration of cortical and hippocampal electrical activity was started 10 min after intra-peritoneal administration of Nembutal Sodium and continued continuously during 72 hour. According to obtained new evidences, serial electrical stimulations of dorsal and lateral hypothalamic Orexin-containing neurons significantly accelerate recovery of wakefulness, sleep homeostasis, disturbed because of barbiturate anesthesia induced artificial sleep and different behavioral states of sleep-wakefulness cycle. Hypothalamic Orexin-containing neurons can be considered as the cellular targets for regulating of sleep homeostasis through the acceleration of recovery of wakefulness, and SWC in general, from barbiturate anesthesia-induced deep sleep. PMID:26719553

  8. Radioactivity in the environment

    International Nuclear Information System (INIS)

    The book summarizes general concepts on radiation, nuclear structure, radioactivity and the interaction of the nuclear radiation with matter. It describes also the basic principles of radio dosimetry. Natural and artificial sources of radiation are reviewed as well as the effects of radiation in man. Medical and industrial applications of ionizing radiation and the pollution produced by the discharge of radioactive materials are outlined. A short review is made of the safety rules and the regulations concerning the protection of the environment

  9. Measurement and analysis of radioactivity induced in CuCrZr by D-T neutrons

    International Nuclear Information System (INIS)

    CuCrZr is used in high heat flux components of ITER and other fusion reactor designs. A CuCrZr alloy of the European Fusion Technology Programme was irradiated with D-T neutrons, and the ?-activities of all nuclides which are relevant up to the recycling limit of the material were measured. The results were analysed with the European Activation System (versions EASY-2001 and EASY-2003). The calculated total activation property of the material was validated within 10%. The long-term radioactivity was estimated to be well below the hands-on limit with an uncertainty of 19%

  10. Decay characteristics of the induced radioactivity in the target cave of a medical cyclotron.

    Science.gov (United States)

    Mukherjee, B

    1997-06-01

    After the transfer of the thick copper target plate irradiated with 30 MeV protons from a medical cyclotron, the gamma dose rate in the target cave was monitored every minute for 25 hours using wall-mounted gamma area monitors. The dose rate decay curve was fitted with four exponential functions. By analysing the slope of the exponentials the traces of radioactive 28Al, 56Mn 24Na and 59Fe were identified. The results were used to minimise personnel radiation exposure during maintenance work on the cyclotron. PMID:9204525

  11. Decay characteristics of the induced radioactivity in the target cave of a medical cyclotron

    International Nuclear Information System (INIS)

    After the transfer of the thick copper target plate irradiated with 30 MeV protons from a medical cyclotron, the gamma dose rate in the target cave was monitored every minute for 25 hours using wall-mounted gamma area monitors. The dose rate decay curve was fitted with four exponential functions. By analysing the slope of the exponentials the traces of radioactive 28Al, 56Mn 24Na and 59Fe were identified. The results were used to minimise personnel radiation exposure during maintenance work on the cyclotron. (Author)

  12. Morning sector drift-bounce resonance driven ULF waves observed in artificially-induced HF radar backscatter

    Directory of Open Access Journals (Sweden)

    L. J. Baddeley

    Full Text Available HF radar backscatter, which has been artificially-induced by a high power RF facility such as the EISCAT heater at Tromsø, has provided coherent radar ionospheric electric field data of unprecedented temporal resolution and accuracy. Here such data are used to investigate ULF wave processes observed by both the CUTLASS HF radars and the EISCAT UHF radar. Data from the SP-UK-OUCH experiment have revealed small-scale (high azimuthal wave number, m -45 waves, predominantly in the morning sector, thought to be brought about by the drift-bounce resonance processes. Conjugate observations from the Polar CAM-MICE instrument indicate the presence of a non-Maxwellian ion distribution function. Further statistical analysis has been undertaken, using the Polar TIMAS instrument, to reveal the prevalence and magnitude of the non-Maxwellian energetic particle populations thought to be responsible for generating these wave types.

    Key words. Ionosphere (active experiments; wave-particle interactions Magnetospheric physics (MHD waves and instabilities

  13. Piezomagnetic effects induced by artificial sources at Mt. Vesuvius (Italy: preliminary results of an experimental survey

    Directory of Open Access Journals (Sweden)

    R. Napoli

    1998-06-01

    Full Text Available In order to put new constrains on magnetic effects associated with mechanical stresses, high frequency monitoring of the geomagnetic field was carried out during a seismic tomography experiment (TOMOVES'96 project at Mt. Vesuvius. Eight proton precession and one Cesium magnetometers were installed along a profile on the SW flank of the volcano to observe possible magnetic changes induced by explosions. Measurements were performed at different sampling frequencies (10 Hz, 0.5 Hz and 0.1 Hz. A remarkable change in the intensity of the magnetic field was observed in only one case. The magnetic transient lasted 12-13 min, reaching the maximum amplitude of slightly less than 15 nT.

  14. Very rough preliminary estimate of the colloidal sodium induced in rock salt by radioactive waste canister radiation

    International Nuclear Information System (INIS)

    Very rough estimates have been made of the total amount, the formation rate and spatial distribution of the Na metal colloid particles induced in rock salt adjacent to four types of radioactive waste canisters. A number of extrapolations were required. Salt immediately adjacent to a lightly shielded, 2.16 kW, high level waste canister could be converted entirely to colloidal Na (and presumably chlorined gas) in 200-400 years. The total Na metal formed will be 250-300 kg. A heavily shielded, 3.3 kW, spent fuel canister will convert roughly 0.3% of the salt at the canister surface to colloidal Na and the total sodium metal will be roughly 0.5 kg. Even at the lowest colloid levels the Na metal formed should greatly influence interactions between canisters and the surrounding salt, particularly if brine enters. 12 references, 6 figures, 2 tables

  15. Artificial piezoelectric grass for energy harvesting from turbulence-induced vibration

    International Nuclear Information System (INIS)

    The primary objective of this research is to develop a deploy-and-forget energy harvesting device for use in low-velocity, highly turbulent fluid flow environments i.e. streams or ventilation systems. The work presented here focuses on a novel, lightweight, highly robust, energy harvester design referred to as piezoelectric grass. This biologically inspired design consists of an array of cantilevers, each constructed with piezoelectric material. When exposed to proper turbulent flow conditions, these cantilevers experience vigorous vibrations. Preliminary results have shown that a small array of piezoelectric grass was able to produce up to 1.0 mW per cantilever in high-intensity turbulent flow having a mean velocity of 11.5 m s?1. According to the literature, this is among the highest output achieved using similar harvesting methods. A distributed parameter model for energy harvesting from turbulence-induced vibration will be introduced and experimentally validated. This model is generalized for the case of a single cantilever in turbulent cross-flow. Two high-sensitivity pressure probes were needed to perform spectral measurements within various turbulent flows. The design and performance of these probes along with calibration and measurement techniques will be discussed. (paper)

  16. Double pulse laser induced breakdown spectroscopy applied to natural and artificial materials from cultural heritages

    International Nuclear Information System (INIS)

    The laser-induced breakdown spectroscopy (LIBS) is an applied physical technique that has shown in recent years its great potential for rapid qualitative analysis of materials. Thanks to the possibility to implement a portable instrument that perform LIBS analysis, this technique is revealed to be particularly useful for in situ analysis in the field of cultural heritages. The purpose of this work is to evaluate the potentiality of LIBS technique in the field of cultural heritages, with respect to the chemical characterization of complex matrix as calcareous and refractory materials for further quantitative analyses on cultural heritages. X-Ray Fluorescence (XRF) analyses were used as reference. Calibration curves of certified materials used as standards were obtained by XRF analyses. The LIBS measurements were performed with a new mobile instrument called Modi (Mobile Double pulse Instrument for LIBS Analysis). The XRF analyses were performed with a portable instrument ArtTAX. LIBS and XRF measurement were performed on both reference materials and samples (bricks and mortars) sampled in the ancient Greek-Roman Theatre of Taormina. Although LIBS measurements performed on reference materials have shown non linear response to concentrations, and so we were not able to obtain quantitative results, an integrated study of XRF and LIBS signals permitted us to distinguish among chemical features and degradation state of measured building materials.

  17. Artificially induced polyploidization in Humulus lupulus L. and its effect on morphological and chemical traits.

    Science.gov (United States)

    Trojak-Goluch, Anna; Skomra, Urszula

    2013-12-01

    Chemically induced polyploids were obtained by the colchicine treatment of shoot tips of Humulus lupulus L. 'Sybilla'. Flow cytometry revealed that most of the treatments resulted in the production of tetraploids. The highest number of tetraploids was obtained when explants were immersed in 0.05% colchicine for 48 h. A field experiment was conducted to compare diploid and tetraploid plants and assess the effect of genome polyploidization on the morphological and chemical characteristics. Tetraploids showed significant differences in relation to diploids. They had thinner and shorter shoots. The influence of chromosome doubling was also reflected in the length, width and area of leaves. The length of female flowers in the tetraploids was significantly shorter than that observed in diploids. Tetraploids produced a diverse number of lupuline glands that were almost twice as large as those observed in diploids. The most distinct effect of genome polyploidization was a significant increase in the weight of cones and spindles. Contents of major chemical constituents of hop cones was little affected by ploidy level. Total essential oils were significantly lower than those in diploids. However there was a significant increase in the proportion of humulene, caryophyllene and farnesene, oils desired by the brewing industry. PMID:24399911

  18. Induced radioactivity in the target station and decay tunnel from a 4MW proton beam

    CERN Document Server

    Agosteo, S; Otto, T; Silari, Marco

    2003-01-01

    An important aspect of a future CERN Neutrino Factory is the material activation arising from a 2.2 GeV, 4 MW proton beam striking a mercury target. A first estimation of the hadronic inelastic interactions and the production of residual nuclei in the target, the magnetic horn, the decay tunnel, the surrounding rock and a downstream dump has been performed by the Monte Carlo hadronic cascade code FLUKA. The aim is both to assess the dose equivalent rate to be expected during maintenance work and to evaluate the amount of residual radioactivity, which will have to be disposed of after the facility has ceased operation. This paper discusses the first results of such calculations.

  19. Cardiomyopathy induced by artificial cardiac pacing: myth or reality sustained by evidence? / Miocardiopatia dilatada induzida por estimulação cardíaca artificial: mito ou realidade sustentada pelas evidências?

    Scientific Electronic Library Online (English)

    Andrés Di Leoni, Ferrari; Anibal Pires, Borges; Luciano Cabral, Albuquerque; Carolina Pelzer, Sussenbach; Priscila Raupp da, Rosa; Ricardo Medeiros, Piantá; Mario, Wiehe; Marco Antônio, Goldani.

    2014-09-01

    Full Text Available A estimulação cardíaca artificial (ECA) é o tratamento mais seguro e eficaz para a bradicardia sintomática irreversível. Nas indicações propícias, pode trazer grande benefício clínico. Contudo, as evidências mostram que a ação da ECA geraria, em alguns casos, efeitos deletérios à estrutura e fisiolo [...] gia cardíacas. Este potencial efeito negativo da ECA convencional poderia ser mais acentuado principalmente em pacientes com comprometimento prévio da função ventricular esquerda e, sobretudo, quando o eletrodo é colocado em posição apical do ventrículo direito (VD). Intrigante é, contudo, que após quase 6 décadas de ECA do VD, apenas uma reduzida parcela de pacientes apresenta esta condição clinicamente manifesta. Os determinantes do surgimento ou não da cardiopatia por ECA não estão totalmente esclarecidos. Ainda é motivo de debate a existência de uma relação de causalidade entre o padrão de BRE artificial secundário à ativação antifisiológica ventricular, alterações da dinâmica contrátil ventricular, e condições clínicas (disfunção sistólica prévia, cardiopatia estrutural preexistente, tempo desde o implante) ou elétricas (duração do intervalo QRS, dose percentual de estimulação ventricular). Esta revisão aborda dados contemporâneos sobre esta nova entidade e discute alternativas de como utilizar a ECA neste contexto, com ênfase na terapia de ressincronização cardíaca. Abstract in english Implantable cardiac pacing systems are a safe and effective treatment for symptomatic irreversible bradycardia. Under the proper indications, cardiac pacing might bring significant clinical benefit. Evidences from literature state that the action of the artificial pacing system, mainly when the vent [...] ricular lead is located at the apex of the right ventricle, produces negative effects to cardiac structure (remodeling, dilatation) and function (dissinchrony). Patients with previously compromised left ventricular function would benefit the least with conventional right ventricle apical pacing, and are exposed to the risk of developing higher incidence of morbidity and mortality for heart failure. However, after almost 6 decades of cardiac pacing, just a reduced portion of patients in general would develop these alterations. In this context, there are not completely clear some issues related to cardiac pacing and the development of this cardiomyopathy. Causality relationships among QRS widening with a left bundle branch block morphology, contractility alterations within the left ventricle, and certain substrates or clinical (previous systolic dysfunction, structural heart disease, time from implant) or electrical conditions (QRS duration, percentage of ventricular stimulation) are still subjecte of debate. This review analyses contemporary data regarding this new entity, and discusses alternatives of how to use cardiac pacing in this context, emphasizing cardiac resynchronization therapy.

  20. Benchmark Studies of Induced Radioactivity Produced in LHC Materials, Pt I: Remanent Dose Rates

    Energy Technology Data Exchange (ETDEWEB)

    Brugger, M.; Mayer, S.; Roesler, S.; Ulrici, L.; /CERN; Khater, H.; Prinz, A.; Vincke, H.; /SLAC

    2006-04-12

    Samples of materials which will be used in the LHC machine for shielding and construction components were irradiated in the stray radiation field of the CERN-EU high-energy reference field facility. After irradiation, the specific activities induced in the various samples were analyzed with a high-precision gamma spectrometer at various cooling times, allowing identification of isotopes with a wide range of half-lives. Furthermore, the irradiation experiment was simulated in detail with the FLUKA Monte Carlo code. A comparison of measured and calculated specific activities shows good agreement, supporting the use of FLUKA for estimating the level of induced activity in the LHC.

  1. Artificial intelligence

    CERN Document Server

    Hunt, Earl B

    1975-01-01

    Artificial Intelligence provides information pertinent to the fundamental aspects of artificial intelligence. This book presents the basic mathematical and computational approaches to problems in the artificial intelligence field.Organized into four parts encompassing 16 chapters, this book begins with an overview of the various fields of artificial intelligence. This text then attempts to connect artificial intelligence problems to some of the notions of computability and abstract computing devices. Other chapters consider the general notion of computability, with focus on the interaction bet

  2. Artificial regressions

    OpenAIRE

    Davidson, Russell; MacKinnon, James

    2001-01-01

    Associated with every popular nonlinear estimation method is at least one 'artificial' linear regression. We define an artificial regression in terms of three conditions that it must satisfy. Then we show how artificial regressions can be useful for numerical optimization, testing hypotheses, and computing parameter estimates. Several existing artificial regressions are discussed and are shown to satisfy the defining conditions, and a new artificial regression for regression models with heter...

  3. Osmosis-induced swelling of Eurobitum bituminized radioactive waste in constant total stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Valcke, E., E-mail: evalcke@sckcen.b [Waste and Disposal Expert Group, Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, 2400 Mol (Belgium); Marien, A.; Smets, S. [Waste and Disposal Expert Group, Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, 2400 Mol (Belgium); Li, X., E-mail: xli@sckcen.b [EIG EURIDICE, Boeretang 200, 2400 Mol (Belgium); Mokni, N., E-mail: nadia.mokni@upc.ed [Department of Geotechnical Engineering and Geosciences, Universidad Politecnica de Catalunya (UPC) (Spain); Olivella, S., E-mail: sebastia.olivella@upc.ed [Department of Geotechnical Engineering and Geosciences, Universidad Politecnica de Catalunya (UPC) (Spain); Sillen, X., E-mail: x.sillen@nirond.b [ONDRAF/NIRAS, Kunstlaan 14, 1210 Brussel (Belgium)

    2010-11-30

    In geological disposal conditions, contact of Eurobitum bituminized radioactive waste, which contains high amounts of the hygroscopic and highly soluble NaNO{sub 3}, with groundwater will result in water uptake and swelling of the waste, and in subsequent leaching of the embedded NaNO{sub 3} and radionuclides. The swelling of and the NaNO{sub 3} leaching from non-radioactive Eurobitum samples, comprised between two stainless steel filters and in contact with 0.1 M KOH, was studied in restricted (semi-confined) swelling conditions, i.e. under a constant total stress, or counterpressure, of 2.2, 3.3, or 4.4 MPa (i.e. oedometer conditions). Four tests were stopped after hydration times between 800 and 1500 days, and the samples were analyzed by micro-focus X-ray Computer Tomography ({mu}CT) and by Environmental Scanning Electron Microscopy (ESEM). The complete set of data enabled a consistent interpretation of the observations and lead to an improved understanding of the phenomenology of the water uptake, swelling, and NaNO{sub 3} leaching in restricted swelling conditions. Under the studied conditions, the bituminous matrix surrounding the NaNO{sub 3} crystals and pores with NaNO{sub 3} solution behaved as a highly efficient semi-permeable membrane, i.e. osmotic processes occurred. In the main part of the leached layers, a high average NaNO{sub 3} concentration and related to this a high osmotic pressure prevailed, explaining why in the studied range the swelling was not measurably affected by the counterpressure. At the interface with the stainless steel filters, a low permeable re-compressed bitumen layer was formed, contributing to the slow release of NaNO{sub 3} compared to the water uptake rate. A fully coupled Chemo-Hydro-Mechanical (CHM) constitutive model has been developed that integrates the key processes involved and that reproduces satisfactorily the results; this is presented in another work. Combination of the experimental and the modelling study allow to conclude that under semi-confined conditions the swelling of the bituminized waste, and its evolution with time, is the result of several transient processes (salts dissolution, diffusion of salts and water, advection, creep, involving a low permeability material with evolving thickness and properties) that moreover are non-linear and strongly coupled.

  4. Osmosis-induced swelling of Eurobitum bituminized radioactive waste in constant total stress conditions

    International Nuclear Information System (INIS)

    In geological disposal conditions, contact of Eurobitum bituminized radioactive waste, which contains high amounts of the hygroscopic and highly soluble NaNO3, with groundwater will result in water uptake and swelling of the waste, and in subsequent leaching of the embedded NaNO3 and radionuclides. The swelling of and the NaNO3 leaching from non-radioactive Eurobitum samples, comprised between two stainless steel filters and in contact with 0.1 M KOH, was studied in restricted (semi-confined) swelling conditions, i.e. under a constant total stress, or counterpressure, of 2.2, 3.3, or 4.4 MPa (i.e. oedometer conditions). Four tests were stopped after hydration times between 800 and 1500 days, and the samples were analyzed by micro-focus X-ray Computer Tomography (?CT) and by Environmental Scanning Electron Microscopy (ESEM). The complete set of data enabled a consistent interpretation of the observations and lead to an improved understanding of the phenomenology of the water uptake, swelling, and NaNO3 leaching in restricted swelling conditions. Under the studied conditions, the bituminous matrix surrounding the NaNO3 crystals and pores with NaNO3 solution behaved as a highly efficient semi-permeable membrane, i.e. osmotic processes occurred. In the main part of the leached layers, a high average NaNO3 concentration and related to this a high osmotic pressure prevailed, explaining why in the studied range the swelling was not measurably affected by the counterpressure. At the interface with the stainless steel filters, a low permeable re-compressed bitumen layer was formed, contributing to the slow release of NaNO3 compared to the water uptake rate. A fully coupled Chemo-Hydro-Mechanical (CHM) constitutive model has been developed that integrates the key processes involved and that reproduces satisfactorily the results; this is presented in another work. Combination of the experimental and the modelling study allow to conclude that under semi-confined conditions the swelling of the bituminized waste, and its evolution with time, is the result of several transient processes (salts dissolution, diffusion of salts and water, advection, creep, involving a low permeability material with evolving thickness and properties) that moreover are non-linear and strongly coupled.

  5. Osmosis-induced swelling of Eurobitum bituminized radioactive waste in constant total stress conditions

    Science.gov (United States)

    Valcke, E.; Marien, A.; Smets, S.; Li, X.; Mokni, N.; Olivella, S.; Sillen, X.

    2010-11-01

    In geological disposal conditions, contact of Eurobitum bituminized radioactive waste, which contains high amounts of the hygroscopic and highly soluble NaNO 3, with groundwater will result in water uptake and swelling of the waste, and in subsequent leaching of the embedded NaNO 3 and radionuclides. The swelling of and the NaNO 3 leaching from non-radioactive Eurobitum samples, comprised between two stainless steel filters and in contact with 0.1 M KOH, was studied in restricted (semi-confined) swelling conditions, i.e. under a constant total stress, or counterpressure, of 2.2, 3.3, or 4.4 MPa ( i.e. oedometer conditions). Four tests were stopped after hydration times between 800 and 1500 days, and the samples were analyzed by micro-focus X-ray Computer Tomography (?CT) and by Environmental Scanning Electron Microscopy (ESEM). The complete set of data enabled a consistent interpretation of the observations and lead to an improved understanding of the phenomenology of the water uptake, swelling, and NaNO 3 leaching in restricted swelling conditions. Under the studied conditions, the bituminous matrix surrounding the NaNO 3 crystals and pores with NaNO 3 solution behaved as a highly efficient semi-permeable membrane, i.e. osmotic processes occurred. In the main part of the leached layers, a high average NaNO 3 concentration and related to this a high osmotic pressure prevailed, explaining why in the studied range the swelling was not measurably affected by the counterpressure. At the interface with the stainless steel filters, a low permeable re-compressed bitumen layer was formed, contributing to the slow release of NaNO 3 compared to the water uptake rate. A fully coupled Chemo-Hydro-Mechanical (CHM) constitutive model has been developed that integrates the key processes involved and that reproduces satisfactorily the results; this is presented in another work. Combination of the experimental and the modelling study allow to conclude that under semi-confined conditions the swelling of the bituminized waste, and its evolution with time, is the result of several transient processes (salts dissolution, diffusion of salts and water, advection, creep, involving a low permeability material with evolving thickness and properties) that moreover are non-linear and strongly coupled.

  6. Effect of atropine and gammahydroxybutyrate on ischemically induced changes in the level of radioactivity in [3H]inositol phosphates in gerbil brain in vivo

    International Nuclear Information System (INIS)

    Brain ischemia in gerbils was induced by ligation of both common carotid arteries for 1 min or 10 min. Sham-operated animals served as controls. Intracerebral injection of [3H]inositol into gerbil brain 16 hr before ischemic insult resulted in equilibration of the label between inositol lipids and water-soluble inositol phosphate. A short ischemic period (1 min) resulted in a statistically significant increase in the radioactivity of inositol triphosphate (IP3) and inositol monophosphate (IP), by about 48% and 79%, respectively, with little change in that of the intermediate inositol biphosphate (IP2), which increased by about 16%. When the ischemic period was prolonged (10 min), an increase in the radioactivity of inositol monophosphate exclusively, by about 84%, was observed. The level of radioactivity in inositol phosphates IP2 and IP3 decreased by about 50%, probably as a consequence of phosphatase activation by the ischemic insult. The agonist of the cholinergic receptor, carbachol, injected intracerebrally (40 micrograms per animal) increased accumulation of radioactivity in all inositol phosphates. The level of radioactivity in IP3, IP2, and IP was elevated by about 40, 23, and 147%, respectively. The muscarinic cholinergic antagonist, atropine, injected intraperitoneally in doses of 100 mg/kg body wt. depressed phosphoinositide metabolism in control animals. The level of radioactivity in water-soluble inositol metabolites in the brain of animals pretreated with atropine was evidently about 32% lower than in untreated animals. Pretreatment with atropine decreased the radioactivity of all inositol phosphates in the brain of animals subjected to 1-min ischemia and the radioactivity of IP in the case of 10-min brain ischemia

  7. Viability study of using the Laser-Induced Breakdown Spectroscopy technique for radioactive waste detection at IPEN-CNEN/SP, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Tunes, Matheus A.; Schon, Claudio G., E-mail: matheus.tunes@ctmsp.mar.mil.br [Universidade de Sao Paulo (USP), SP (Brazil). Departamento de Engenharia Metalugica e de Materiais. Escola Politecnica; Wetter, Niklaus U., E-mail: nuwetter@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    this work a viability study to apply the Laser-Induced Breakdown Spectroscopy (LIBS) technique for radioactive waste characterization was developed using a high power q-switched Nd:YAG rod-Laser, operating at 1064 nm with 9 ns of pulse-width and pulse-to-pulse energy around 10 to 20 mJ. When applied in a non-radioactive deionized water sample, our methodology exhibits a good potential to spectroscopy detection of Hydrogen species with resolution around 0.035 nm at full width at half maximum (FWHM). (author)

  8. Theoretical evaluation of induced radioactivity in food products by electron or X-ray beam sterilization

    International Nuclear Information System (INIS)

    We evaluate first the energy density for electrons or X-ray beams necessary to produce a reference level of 1 kilogray at the maximum of dose, as a function of energy, for electrons and bremsstrahlung photons, based on experimental data obtained on radio-therapy beams, from 4 to 32 MeV, and irradiation beams from production plant CARIC. Then from the production of neutrons on the tungsten target and from (?n) reactions on the deuterium content of the irradiated food, the slowing down and capture of these neutrons is estimated. Radioisotopes can be produced by (?n) reactions on iodine, and to a lesser extent on tin, lead, barium, etc., but the major contribution is neutron activation, where the more critical elements are sodium, chlorine, potassium, magnesium, phosphorus, calcium. Induced activity is compared to natural activity coming from potassium 40, carbon 14 and radium, contained in all foods. For electrons up to 1 Mrad the induced activity remains of the order of a few percent of natural activity, for energies below 10 to 11 MeV. Bremsstrahlung X-ray irradiations can give comparable levels as soon as the energy of the generating electron beam is above 3 MeV. The induced activity decays within a few days. (author)

  9. 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.

    Science.gov (United States)

    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. PMID:25233912

  10. Development of the precise measurement method for gamma-ray energy of neutron induced radioactive nuclides

    International Nuclear Information System (INIS)

    Goal of the research is to develop a new energy calibration method to perform precise measurement of photon energy by gamma-ray spectrometry. Here, we regard reference standard energies to be those of photon of radioactive isotopes measured basing on a laser wavelength of 86Kr (606 nm) together with energy-wavelength conversion factor E? = 1.239 842 44 x 10-6 eV m ±0.03 ppm (CODATA 1986). As such the reference standard we use 192Ir isotope. Deviation of photon energy values between data obtained by photon spectrometry, i.e., the decay gamma-ray analysis and the prompt gamma-ray analysis with Ge or Ge(Li) detectors, and those obtained by crystal diffraction spectrometry, has led that the 'conventional' method of energy calibration for the photon spectrometry is not adequate to the precise energy assignment. A 'new' method has solved this problem by introducing the concept of an instrument function, which is the transfer function between an input signal-shape function and an output (measured) signal-shape function, as summarized in reference 1. Present status of photon energy values has been examined for the nuclear-decay gamma-rays, the nuclear excitation gamma-rays and the mesonic-atom X-rays. At the previous stage of research we evaluated that a commonly-used internal standard method, mainly used for activation analysis study, was inadequate for the precise measurement of photon energy, so far as we use base subtraction method. In the present study, we examined the cause of the inadequacy of a base-subtraction method for obtaining the photopeak line shape for the precise energy measurement. (author)

  11. Artificial sweetener neohesperidin dihydrochalcone showed antioxidative, anti-inflammatory and anti-apoptosis effects against paraquat-induced liver injury in mice.

    Science.gov (United States)

    Shi, Qiong; Song, Xiufang; Fu, Juanli; Su, Chuanyang; Xia, Xiaomin; Song, Erqun; Song, Yang

    2015-12-01

    The present study evaluated the protective effect of artificial sweetener neohesperidin dihydrochalcone (NHDC) against paraquat (PQ)-induced acute liver injury in mice. A single dose of PQ (75mg/kg body weight, i.p.) induced acute liver toxicity with the evidences of increased liver damage biomarkers, aspartate transaminase (AST) and alanine transaminase (ALT) activities in serum. Consistently, PQ decreased the antioxidant capacity by reducing glutathione peroxidase (GP-X), glutathione-S-transferase (GST) and catalase (CAT) activities, glutathione (GSH) level and total antioxidant capacity (T-AOC), as well as increasing reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) levels. Histopathological examination revealed that PQ induced numerous changes in the liver tissues. Immunochemical staining assay indicated the upregulation of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expressions. However, NHDC ameliorates PQ-induced hepatic toxicity in mice by reversing these parameters. Additionally, NHDC significantly inhibited PQ-induced nuclear factor-kappa B (NF-?B) expression and mitochondrial-driven apoptotic signaling. TUNEL assay confirmed that PQ-induced apoptosis was relieved by NHDC. In conclusion, these findings suggested that NHDC showed potent antioxidant, anti-inflammatory and anti-apoptotic effects against PQ-induced acute liver damage. PMID:26362205

  12. Study of the sorption of some artificial radioelements by pelitic sediments for the purpose of application to the radioactive labeling of these materials

    International Nuclear Information System (INIS)

    The radioactive labeling of silt is in itself difficult, the main obstacle being the identity of the dynamic properties of these sediments before and after labeling. The aim of this study is to examine in detail the labeling processes, the methods used and their success with regard to the above criterion. The author, having shown that labeling by direct activation and by simulators such as ground glass fail to fulfil the conditions of a good mixture, explores surface fixation techniques for 198Au, 51Cr, 46Sc and 192Ir. The ideal labeling conditions are determined and evidence is collected in relation to the actual fixation of the tracer. Finally the dynamic properties of a natural sediment are compared with those of a sediment labeled by the methods described here. (author)

  13. Thermally induced motion of marine sediments resulting from disposal of radioactive wastes

    International Nuclear Information System (INIS)

    Coupled creep and heat transfer calculations have been performed to assess the sensitivity of heat load, viscosity, and canister density on the motion of waste canisters buried in marine sediments. Results indicate that no upward movement is predicted for heat loads remaining within the metallurgical and geochemical constraints placed on the temperature of sediments near the canister for the times analyzed. Upward movement of the canister is again not observed in calculations involving reasonable variations of the sediment viscosity and canister density. Maximum effective deviatoric stress levels due to thermally induced differential body forces are significantly less than the sediment's short term peak strength

  14. Artificial Limbs

    Science.gov (United States)

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

  15. Induced radioactive continuum background in the integral spectrometer (SPI) germanium detectors

    International Nuclear Information System (INIS)

    This paper presents a detailed study of the ? decay continuum background in a spaceborn Ge spectrometer (SPI) and methods for its reduction. In the nuclear ?-ray line energy range (10 keV, 20 MeV), much of the continuum background in the Ge spectrometers is due to the cosmic-ray generated protons and neutrons interacting in the detectors themselves. We have performed Monte Carlo simulations to calculate the neutron spectrum inside the BGO shield of the spectrometer SPI, thus allowing the calculation of the continuum background induced by the ?- and ?+ decays of the Ge residuals nuclides. It is shown that if we use the Pulse Shape Discrimination (PSD) and energetic signatures in energy ranges well chosen to reduce the background, the main effect is an improvement of the sensitivity of SPI

  16. Determination of the neutron and gamma dose rates and heatings induced by radioactive wastes in repository geological salt formations

    International Nuclear Information System (INIS)

    In the frame of two CCE working projects called the High Active Waste (HAW) program and the Active Handling Experiment (AHE) program, German Institutes and Companies (GSF, KfK, DBE) and CEA-ANDRA lead a collaboration on the subject of a final disposal in salt formation. The two studies concern the same geological configuration: the ASSE salt mine in Germany. But, the purposes are different and complementary. In the HAW project, the study relates to the feasibility in the geological point of view, of a high level radioactive wastes final disposal. The purpose of the calculations is to obtain the information on the effects of the gamma radiation in the salt (gases formation by radiolysis, thermomechanical modifications of the rock...). The informations given are the dose rate and heating levels induced by the different gamma rays. A physical study has been led to well define the gamma source term taking into account the bremsstrahlung phenomena linked to the different beta emission. The AHE project concerns the handling and the repository aspects of spent fuel which was not processed. It means the feasibility of the program, in the radioprotection point of view. The effect of the neutron wall gallery backscattering phenomena, on the dose rate level, was studied. An experiment is being elaborated in the ASSE mine which the measurement results will be compared with the calculation ones. A good agreement will allow to apply this calculation scheme in the real planned disposal configurations. (authors). 6 figs., 2 tabs., 5 refs

  17. Bone marrow mesenchymal stem cell implantation for the treatment of radioactivity?induced acute skin damage in rats.

    Science.gov (United States)

    Zheng, Kai; Wu, Weizhen; Yang, Shunliang; Huang, Lianghu; Chen, Jin; Gong, Chungui; Fu, Zhichao; Zhang, Linlin; Tan, Jianming

    2015-11-01

    The present study aimed to observe the role of mesenchymal stem cells (MSCs) in the repair of acute skin damage caused by radiation. Rat bone marrow MSCs (BMSCs) were isolated and cultured in vitro. A rat model of radiation?induced acute skin damage was established by irradiation of the hind legs of Sprague-Dawley rats using a linear accelerator (45 Gy). After irradiation, rats were randomly divided into two groups: BMSC group and control group. Rats in the BMSC group were treated with a tail vein injection of 2x106 BMSCs (1 ml) immediately after irradiation and a local multipoint injection of 2x106 BMSCs at the injured area two weeks later. Then the wound healing of each rat was observed. The expression of transforming growth factor (TGF)??1, stromal cell?derived factor-1 (SDF?1) and prostaglandin E2 (PGE2) in the wounded tissues was determined by immunohistochemistry. The results demonstrated that skin damage was milder in the BMSC group than in the control group. Moreover, the speed of healing in the BMSC group was better than that in the control group. In addition, the wound score, it was significantly lower in the BMSC group than in the control group (Pskin and promote the repair of acute radioactive skin injury. Thus, may be developed as a novel treatment for wound healing. PMID:26323987

  18. Artificial graphite

    International Nuclear Information System (INIS)

    Data on the structure, mechanical, chemical and physical properties of artificial graphites are systematized. Problems on preparation of artificial graphite and effect of manufacturing factors on its properties are described. Fields of artificial graphite implementation, in particular reactor engineering, are pointed out. Specific behaviour of graphite in operation is described

  19. Study of a method of detection for natural carbon-14 using a liquid scintillator, recent variations in the natural radio-activity due to artificial carbon-14 (1963)

    International Nuclear Information System (INIS)

    Among the various natural isotopes of carbon, a radioactive isotope, carbon-14, is formed by the action of secondary neutrons from cosmic rays on nitrogen in the air. Until 1950, the concentration of this isotope in ordinary carbon underwent weak fluctuations of about 2-3 per cent. The exact measurement of this concentration 6 X 1012 Ci/gm of carbon, and of its fluctuations, are difficult and in the first part of this report a highly sensitive method is given using a liquid scintillator. Since 1950 this natural activity has shown large fluctuations because of the carbon-14 formed during nuclear explosions, and in the second part, the evolution in France of this specific activity of carbon in the atmosphere and biosphere is examined. In the last part is studied the local increase in carbon activity in the atmosphere around the Saclay site, an increase caused by the carbon-14 given off as C14O2, by the reactors cooled partially with exterior air. (author)

  20. Study of the artificial radioactivity of the marine medium using gamma spectrometry (1962-1966); Etude de la radioactivite artificielle du milieu marin par spectrometrie gamma (1962-1966)

    Energy Technology Data Exchange (ETDEWEB)

    Chesselet, R. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1969-07-01

    The results described in this study are relative to the artificial radioactivity of such elements as zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 and praseodymium-144 which were present in the atmospheric fallout between 1962 and 1964, and their incidence in superficial marine waters. Various physical, chemical or biological processes are studied by a high sensitivity gamma ray spectrometry technic, using those radioelements as 'tracers'. The change of state in sea water of an important fraction (about 50 per cent) of the radioactive particles going into the soluble phase - this phenomenon was not expected for those radioelements - controls the processes of accumulation in the planktonic biomass and the diffusion towards deeper waters. On the other hand, an 'in situ' spectrometry method is described. It enables the direct measurement in the sea of very low concentrations of some gamma ray emitters. The application of this method has made possible to carry out numerous observations in the surface waters of the Western Mediterranean sea and in the Bay of Biscay. It is shown that the mixing depth is closely connected to the depth of the thermocline. An accumulation process at this level is observed. The diffusion coefficients are similar to the thermal turbulent coefficient. The existence during several months of 'compartments' is established for the surface waters of the Bay of Biscay. From the establishment of the budget of fall-out, a comparative study shows that the rate of radioactive fallout on the maritime zone considered is always two to three times higher than on the neighbouring continental regions. Several explanations of this phenomenon are discussed. (author) [French] Les resultats decrits dans cette etude concernent la radioactivite artificielle sous forme de zirconium-95, niobium-95, ruthenium-103, ruthenium-106, cerium-141, cerium-144 et praseodyme-144 apportee par la retombee atmospherique entre 1962 et 1964 et les incidences de cette retombee dans les eaux marines superficielles. Considerant les radioelements etudies comme des 'traceurs' dans le milieu marin, divers processus physiques, chimiques ou biologiques ont ete etudies par spectrometrie gamma a haute sensibilite. Le passage en phase soluble dans l'eau de mer d'une fraction importante (environ 50 pour cent) de l'activite liee aux poussieres radioactives, phenomene qui n'etait pas previsible pour les radioelements etudies, gouverne les processus d'accumulation dans la biomasse planctonique et la diffusion vers les eaux plus profondes. Par ailleurs, une methode de spectrometrie 'in situ' permettant de mesurer directement dans la mer de tres faibles concentrations en certains radionuclides emetteurs gamma est decrite. L'application de cette methode a permis de nombreuses observations dans les eaux de surface de la Mediterranee occidentale et du Golfe de Gascogne. On montre quo la profondeur de melange est etroitement liee a celle de la thermocline. Un processus d'accumulation au niveau de celle-ci est constate. Les coefficients de diffusion sont voisins du coefficient de diffusion thermique turbulente. L'existence de compartiments qui subsistent pendant plusieurs mois dans la masse des eaux de surface du Golfe de Gascogne est mise en evidence. Grace aux bilans effectues, une etude comparative montre que le taux de retombees radioactives sur les surfaces maritimes est toujours deux a trois fois superieur a celui sur les regions continentales voisines. Diverses explications de ce phenomene sont discutees. (auteur)

  1. An active artificial cornea with the function of inducing new corneal tissue generation in vivo-a new approach to corneal tissue engineering

    International Nuclear Information System (INIS)

    An active artificial cornea which can perform the function of inducing new cornea generation in vivo but does not need culture cells in vitro and which has similar optical and mechanical properties to those of the human cornea was constructed. An animal keratoplasty experiment using the artificial cornea as the implant showed that the animals' corneas could keep smooth surface and clear stroma postoperatively, and that the repopulation of the host's keratocytes, the degradation of the implant and new corneal tissue generation were completed at 5-6 months after surgery. Such an artificial cornea has several advantages over other corneal equivalents constructed in the typical way of tissue engineering: in having similar mechanical and optical properties to those of the human cornea and with no exogenetic cells, it can be used universally in different implantation surgeries without immunoreaction; it is easy to prepare and process into different shapes and sizes on a large scale, and suitable for long-distance transportation and long-term storage. All these characteristics make it a new approach to cornea tissue engineering having potential in many clinical applications

  2. Amersham's high radioactivity

    International Nuclear Information System (INIS)

    An account is given of the history, organisation and work of Amersham International, to produce radioactive and other products for use in medical diagnosis and therapy, in research in the life sciences, and in industrial processes and control systems. The account covers the developments from the war-time work of Thorium Ltd., on naturally occurring radioactive materials, through the post-war expansion into the field of artificial radioisotopes, as the Radiochemical Centre (part of the UK Atomic Energy Authority), to the recent reorganisation and privatization. The width of the range of activities and products available is emphasised, with examples. (U.K.)

  3. Processing semblances induced through inter-postsynaptic functional LINKs, presumed biological parallels of K-lines proposed for building artificial intelligence

    Directory of Open Access Journals (Sweden)

    Kunjumon I Vadakkan

    2011-07-01

    Full Text Available The internal sensation of memory, which is available only to the owner of an individual nervous system, is difficult to analyze for its basic elements of operation. We hypothesize that associative learning induces the formation of functional LINK between the postsynapses. During memory retrieval, the activation of either postsynapse re-activates the functional LINK evoking a semblance of sensory activity arriving at its opposite postsynapse, nature of which defines the basic unit of virtual internal sensation - namely, semblion. Neuronal networks that undergo continuous oscillatory activity at certain levels of their organization induce semblions enabling the system to continuously learn, self-organize, and demonstrate instantiation, features that can be utilized for developing artificial intelligence (AI. Suitability of the inter-postsynaptic functional LINKs to meet the expectations of Minsky’s K-lines, basic elements of a memory theory generated to develop AI and methods to replicate semblances outside the nervous system are explained.

  4. Artificial heart

    OpenAIRE

    Nishta, B.V.

    2014-01-01

    An artificial heart is a device that replaces the heart. Artificial hearts are typically used to bridge the time to heart transplantation, or to permanently replace the heart in case heart transplantation is impossible. Although other similar inventions preceded it are going back to the late 1940s, the first artificial heart to be successfully implanted in a human was the Jarvik-7, designed by Robert Jarvik and implemented in 1982. When you are citing the document, use the following link h...

  5. Predicting typhoon-induced storm surge tide with a two-dimensional hydrodynamic model and artificial neural network model

    OpenAIRE

    W.-B. Chen; W.-C. Liu; M.-H. Hsu

    2012-01-01

    Precise predictions of storm surges during typhoon events have the necessity for disaster prevention in coastal seas. This paper explores an artificial neural network (ANN) model, including the back propagation neural network (BPNN) and adaptive neuro-fuzzy inference system (ANFIS) algorithms used to correct poor calculations with a two-dimensional hydrodynamic model in predicting storm surge height during typhoon events. The two-dimensional model has a fine horizontal resol...

  6. Radioactive surveillance in peruvian foods

    International Nuclear Information System (INIS)

    The concentrations of radionuclides in some Peruvian foodstuffs have been measured. The results of this study can be considered as a first step towards calculating the baseline levels of radioactivity in foodstuffs from Peru. The overall intake of Cs-137 is quite low and no significant radionuclide contamination was found. Therefore the results shows that, between 1990 and 2006, consumers' exposure to artificially produced radioactivity via the food chain, is below the peruvian annual dose limit to members of the public of 1 mSv (millisievert) for all artificial sources of radiation. (author)

  7. Regional blood flow distribution in dog during induced hypotension and low cardiac output. Spontaneous breathing versus artificial ventilation.

    OpenAIRE

    Viires, N; Sillye, G; Aubier, M; Rassidakis, A; Roussos, C

    1983-01-01

    Respiratory muscle blood flow and organ blood flow was studied in two groups of dogs with radioactively labeled microspheres to assess the influence of the working respiratory muscles on the regional distribution of blood flow when arterial pressure and cardiac output were lowered by pericardial tamponade. In one group (n = 6), the dogs were paralyzed and mechanically ventilated (Mv), while in the other (n = 6), they were left to breathe spontaneously (Sb). Cardiac output fell to 30% of contr...

  8. Osmosis-induced water uptake by Eurobitum bituminized radioactive waste and pressure development in constant volume conditions

    Science.gov (United States)

    Mariën, A.; Mokni, N.; Valcke, E.; Olivella, S.; Smets, S.; Li, X.

    2013-01-01

    The chemo-hydro-mechanical (CHM) interaction between swelling Eurobitum radioactive bituminized waste (BW) and Boom Clay is investigated to assess the feasibility of geological disposal for the long-term management of this waste. These so-called compatibility studies include laboratory water uptake tests at the Belgian Nuclear Research Center SCK•CEN, and the development of a coupled CHM formulation for Eurobitum by the International Center for Numerical Methods and Engineering (CIMNE, Polytechnical University of Cataluña, Spain). In the water uptake tests, the osmosis-induced swelling, pressure increase and NaNO3 leaching of small cylindrical BW samples (diameter 38 mm, height 10 mm) is studied under constant total stress conditions and nearly constant volume conditions; the actual geological disposal conditions should be intermediate between these extremes. Two nearly constant volume tests were stopped after 1036 and 1555 days to characterize the morphology of the hydrated BW samples and to visualize the hydrated part with microfocus X-ray Computer Tomography (?CT) and Environmental Scanning Electron Microscopy (ESEM). In parallel, a coupled CHM formulation is developed that describes chemically and hydraulically coupled flow processes in porous materials with salt crystals, and that incorporates a porosity dependent membrane efficiency, permeability and diffusivity. When Eurobitum BW is hydrated in (nearly) constant volume conditions, the osmosis-induced water uptake results in an increasing pressure to values that can be (in theory) as high as 42.8 MPa, being the osmotic pressure of a saturated NaNO3 solution. After about four years of hydration in nearly constant volume water uptake tests, pressures up to 20 MPa are measured. During this hydration period only the outer layers with a thickness of 1-2 mm were hydrated (as derived from ?CT and ESEM analyses), and only about 10-20% of the initial NaNO3 content was released by the samples. In the studied test conditions, the rates of water uptake and NaNO3 leaching are low because of the low porosity, and thus low permeability, of the hydrated BW samples in combination with a highly efficient semi-permeable bitumen membrane. In contrast to the hydration in free swelling conditions, the increase in porosity is limited by the high pressures in the nearly constant volume tests. Furthermore, at the interface with the stainless steel filters, a low permeable re-compressed bitumen layer is formed, as observed on the ESEM images. The experimental results of pressure increase and NaNO3 leaching, as well as observations on ?CT and ESEM images (e.g. compression of leached layers, high dissolved NaNO3 concentration in hydrated BW after about four years), were reproduced rather successfully by the coupled CHM formulation for Eurobitum BW. A long-term model prediction of the evolution of the osmosis-induced pressure in the nearly constant volume tests shows that the pressure would reach a maximal value of about 20 MPa after about 5.5 years, after which the pressure would start to decrease. After 10,000 days (˜27 years) the pressure would have decreased to a value of ˜2 MPa.

  9. Osmosis-induced water uptake by Eurobitum bituminized radioactive waste and pressure development in constant volume conditions

    Energy Technology Data Exchange (ETDEWEB)

    Marieen, A., E-mail: amarien@sckcen.be [Waste and Disposal Expert Group, Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, 2400 Mol (Belgium); Mokni, N., E-mail: Nadia.mokni@upc.edu [Department of Geotechnical Engineering and Geosciences, Universidad Politecnica de Catalunya (UPC), Calle Gran Capitan, s/n, Edificio C-1, 08034 Barcelona (Spain); Valcke, E. [Waste and Disposal Expert Group, Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, 2400 Mol (Belgium); Olivella, S. [Department of Geotechnical Engineering and Geosciences, Universidad Politecnica de Catalunya (UPC), Calle Gran Capitan, s/n, Edificio C-1, 08034 Barcelona (Spain); Smets, S. [Waste and Disposal Expert Group, Belgian Nuclear Research Centre (SCK-CEN), Boeretang 200, 2400 Mol (Belgium); Li, X., E-mail: xli@sckcen.be [EIG EURIDICE, Boeretang 200, 2400 Mol (Belgium)

    2013-01-15

    Highlights: Black-Right-Pointing-Pointer The water uptake by Eurobitum is studied to judge the safety of geological disposal. Black-Right-Pointing-Pointer High pressures of up to 20 MPa are measured in constant volume water uptake tests. Black-Right-Pointing-Pointer The morphology of leached Eurobitum samples is studied with {mu}CT and ESEM. Black-Right-Pointing-Pointer The observations are reproduced by an existing CHM formulation for Eurobitum. - Abstract: The chemo-hydro-mechanical (CHM) interaction between swelling Eurobitum radioactive bituminized waste (BW) and Boom Clay is investigated to assess the feasibility of geological disposal for the long-term management of this waste. These so-called compatibility studies include laboratory water uptake tests at Belgian Nuclear Research Center SCK-CEN, and the development of a coupled CHM formulation for Eurobitum by the International Center for Numerical Methods and Engineering (CIMNE, Polytechnical University of Cataluna, Spain). In the water uptake tests, the osmosis-induced swelling, pressure increase and NaNO{sub 3} leaching of small cylindrical BW samples (diameter 38 mm, height 10 mm) is studied under constant total stress conditions and nearly constant volume conditions; the actual geological disposal conditions should be intermediate between these extremes. Two nearly constant volume tests were stopped after 1036 and 1555 days to characterize the morphology of the hydrated BW samples and to visualize the hydrated part with microfocus X-ray Computer Tomography ({mu}CT) and Environmental Scanning Electron Microscopy (ESEM). In parallel, a coupled CHM formulation is developed that describes chemically and hydraulically coupled flow processes in porous materials with salt crystals, and that incorporates a porosity dependent membrane efficiency, permeability and diffusivity. When Eurobitum BW is hydrated in (nearly) constant volume conditions, the osmosis-induced water uptake results in an increasing pressure to values that can be (in theory) as high as 42.8 MPa, being the osmotic pressure of a saturated NaNO{sub 3} solution. After about four years of hydration in nearly constant volume water uptake tests, pressures up to 20 MPa are measured. During this hydration period only the outer layers with a thickness of 1-2 mm were hydrated (as derived from {mu}CT and ESEM analyses), and only about 10-20% of the initial NaNO{sub 3} content was released by the samples. In the studied test conditions, the rates of water uptake and NaNO{sub 3} leaching are low because of the low porosity, and thus low permeability, of the hydrated BW samples in combination with a highly efficient semi-permeable bitumen membrane. In contrast to the hydration in free swelling conditions, the increase in porosity is limited by the high pressures in the nearly constant volume tests. Furthermore, at the interface with the stainless steel filters, a low permeable re-compressed bitumen layer is formed, as observed on the ESEM images. The experimental results of pressure increase and NaNO{sub 3} leaching, as well as observations on {mu}CT and ESEM images (e.g. compression of leached layers, high dissolved NaNO{sub 3} concentration in hydrated BW after about four years), were reproduced rather successfully by the coupled CHM formulation for Eurobitum BW. A long-term model prediction of the evolution of the osmosis-induced pressure in the nearly constant volume tests shows that the pressure would reach a maximal value of about 20 MPa after about 5.5 years, after which the pressure would start to decrease. After 10,000 days ({approx}27 years) the pressure would have decreased to a value of {approx}2 MPa.

  10. Osmosis-induced water uptake by Eurobitum bituminized radioactive waste and pressure development in constant volume conditions

    International Nuclear Information System (INIS)

    Highlights: ? The water uptake by Eurobitum is studied to judge the safety of geological disposal. ? High pressures of up to 20 MPa are measured in constant volume water uptake tests. ? The morphology of leached Eurobitum samples is studied with ?CT and ESEM. ? The observations are reproduced by an existing CHM formulation for Eurobitum. - Abstract: The chemo-hydro-mechanical (CHM) interaction between swelling Eurobitum radioactive bituminized waste (BW) and Boom Clay is investigated to assess the feasibility of geological disposal for the long-term management of this waste. These so-called compatibility studies include laboratory water uptake tests at Belgian Nuclear Research Center SCK-CEN, and the development of a coupled CHM formulation for Eurobitum by the International Center for Numerical Methods and Engineering (CIMNE, Polytechnical University of Cataluña, Spain). In the water uptake tests, the osmosis-induced swelling, pressure increase and NaNO3 leaching of small cylindrical BW samples (diameter 38 mm, height 10 mm) is studied under constant total stress conditions and nearly constant volume conditions; the actual geological disposal conditions should be intermediate between these extremes. Two nearly constant volume tests were stopped after 1036 and 1555 days to characterize the morphology of the hydrated BW samples and to visualize the hydrated part with microfocus X-ray Computer Tomography (?CT) and Environmental Scanning Electron Microscopy (ESEM). In parallel, a coupled CHM formulation is developed that describes chemically and hydraulically coupled flow processes in porous materials with salt crystals, and that incorporates a porosity dependent membrane efficiency, permeability and diffusivity. When Eurobitum BW is hydrated in (nearly) constant volume conditions, the osmosis-induced water uptake results in an increasing pressure to values that can be (in theory) as high as 42.8 MPa, being the osmotic pressure of a saturated NaNO3 solution. After about four years of hydration in nearly constant volume water uptake tests, pressures up to 20 MPa are measured. During this hydration period only the outer layers with a thickness of 1–2 mm were hydrated (as derived from ?CT and ESEM analyses), and only about 10–20% of the initial NaNO3 content was released by the samples. In the studied test conditions, the rates of water uptake and NaNO3 leaching are low because of the low porosity, and thus low permeability, of the hydrated BW samples in combination with a highly efficient semi-permeable bitumen membrane. In contrast to the hydration in free swelling conditions, the increase in porosity is limited by the high pressures in the nearly constant volume tests. Furthermore, at the interface with the stainless steel filters, a low permeable re-compressed bitumen layer is formed, as observed on the ESEM images. The experimental results of pressure increase and NaNO3 leaching, as well as observations on ?CT and ESEM images (e.g. compression of leached layers, high dissolved NaNO3 concentration in hydrated BW after about four years), were reproduced rather successfully by the coupled CHM formulation for Eurobitum BW. A long-term model prediction of the evolution of the osmosis-induced pressure in the nearly constant volume tests shows that the pressure would reach a maximal value of about 20 MPa after about 5.5 years, after which the pressure would start to decrease. After 10,000 days (?27 years) the pressure would have decreased to a value of ?2 MPa.

  11. Artificial Intelligence.

    Science.gov (United States)

    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 also briefly…

  12. Artificial blood

    Directory of Open Access Journals (Sweden)

    Sarkar Suman

    2008-01-01

    Full Text Available 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.

  13. Induced radioactivity and influence of materials selection in deuterium-deuterium and deuterium-tritium fusion reactors

    International Nuclear Information System (INIS)

    The radioactivity, biological hazard potential, and afterheat levels in the deuterium-deuterium (D-D) fuel cycle fusion reactor, SATYR, have been evaluated for two types of structural materials: ferritic steel (HT-9) and sintered aluminum product. Results are compared to the corresponding levels in the deuterium-tritium (D-T) fuel cycle systems, STARFIRE and WITAMIR-I, both during operation and after plant decomissioning. The influence of blanket replacements on the radioactivity levels has been considered in the comparative analysis. It has been found that the long-term radioactivity level (100 to 1000 yr after plant shutdown) in the ferritic steel blanket of the SATYR design is somewhat higher, by a factor of 2 to 6, than that found for a D-T reactor system employing the same structural alloy. The high levels are attributed to the softer spectrum and the larger structure volume fraction encountered in the D-D machines. However, the levels during plant operation ( about30 yr) are comparable. Isotopic tailoring and elemental substitution in alloys to reduce the long-term radioactivity levels in the SATYR design are discussed. It is found that three orders of magnitude reduction in radioactivity levels can be achieved by isotopically tailoring the molybdenum in the ferritic steel to 100% 97Mo. The elemental substitution of vanadium for nickel and molybdenum in ferritic steels is shown to reduce long-term radioactivity levels by four orders of magnitude. These low levels at long times after shutdown are below those found for blankets using aluminum alloy structure. The results make clear that elemental composition should be a primary consideration in alloy formulation if the goal of a low radioactivity level in fusion reactor radwaste is to be achieved

  14. Ambient radioactivity levels and radiation doses. Annual report 2012; Umweltradioaktivitaet und Strahlenbelastung. Jahresbreicht 2012

    Energy Technology Data Exchange (ETDEWEB)

    Bernhard-Stroel, Claudia; Hachenberger, Claudia; Trugenberger-Schnabel, Angela; Loebke-Reinl, Angelika; Peter, Josef (comps.) [Bundesamt fuer Strahlenschutz, Salzgitter (Germany)

    2014-06-15

    The annual report 2012 on ambient radioactivity levels and radiation doses covers the following issues: Part A: General information: natural environmental radioactivity; artificial radioactivity in the environment; occupational radiation exposure; radiation exposures from medical applications; the handling of radioactive materials and sources of ionizing radiation; non-ionizing radiation. Part B: Current data and their evaluation: natural environmental radioactivity; artificial radioactivity in the environment; occupational radiation exposures; radiation exposures from medical applications; the handling of radioactive materials and sources of ionizing radiation; non-ionizing radiation. The report includes data on the stock of radioactive waste, radiation accidents and unusual events.

  15. Environmental radioactivity in the antarctic station

    International Nuclear Information System (INIS)

    Study about environmental radioactivity in the Peruvian antarctic station Machu Pichu they were carried out during the last three periods to the southern summer. The objective of the project it is to evaluate environmental component in order to elaborate a study it base on the levels background radioactivity and artificial in the antarctic region

  16. Artificial intelligence

    CERN Document Server

    Ennals, J R

    1987-01-01

    Artificial Intelligence: State of the Art Report is a two-part report consisting of the invited papers and the analysis. The editor first gives an introduction to the invited papers before presenting each paper and the analysis, and then concludes with the list of references related to the study. The invited papers explore the various aspects of artificial intelligence. The analysis part assesses the major advances in artificial intelligence and provides a balanced analysis of the state of the art in this field. The Bibliography compiles the most important published material on the subject of

  17. Measurements of D-T neutron induced radioactivity in plasma-facing materials and their role in qualification of activation cross-section libraries and codes

    International Nuclear Information System (INIS)

    The D-T neutron-induced radioactivity constitutes one of the foremost issues in fusion reactor design. The validation of activation cross-sections and decay data libraries is one of the important requirements for validating ITER design from safety and waste disposal viewpoints. An elaborate, experimental program was initiated in 1988, under USDOE-JAERI collaborative program, to validate the radioactivity codes/libraries. The measurements of decay-? spectra from irradiated, high purity samples of Al, Si, Ti, V, Cr, Mn-Cu alloy, Fe, Co, Ni, Cu, stainless steel 316 (AISI 316), Zn, Zr, Nb, Mo, In, Sn, Ta, W, and Pb, among others, were conducted under D-T neutron fluences varying from 1.6 x 1010ncm-2 to 6.1 x 1013ncm-2. As many as 14 neutron energy spectra were covered for a number of materials. The analysis of isotopic activities of the irradiated materials using activation cross-section libraries of four leading radioactivity codes, i.e. ACT4/THIDA-2, REAC-3, DKR-ICF, and RACC, has shown large discrepancies among the calculations, on the one hand, and between the calculations and the measurements, on the other. A discussion is also presented on definition and obtention of safety cum quality factors for various activation libraries. (orig.)

  18. Artificial Reefs

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — An artificial reef is a human-made underwater structure, typically built to promote marine life in areas with a generally featureless bottom, control erosion, block...

  19. Artificial sweeteners

    DEFF Research Database (Denmark)

    Raben, Anne Birgitte; Richelsen, Bjørn

    2012-01-01

    PURPOSE OF REVIEW: Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie-containing sweeteners. The purpose of this review is to summarize the current evidence on the effect of artificial sweeteners on body weight, appetite, and risk markers for diabetes and CVD in ...

  20. Artificial sweeteners

    DEFF Research Database (Denmark)

    Raben, Anne Birgitte; Richelsen, Bjørn

    2012-01-01

    Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie-containing sweeteners. The purpose of this review is to summarize the current evidence on the effect of artificial sweeteners on body weight, appetite, and risk markers for diabetes and CVD in humans.

  1. Use of artificial tracers in hydrology

    International Nuclear Information System (INIS)

    The IAEA has convened an Advisory Group Meeting with the following objectives: To define the role of artificial radioactive tracers for water tracing in comparison with other non-radioactive tracers. To evaluate the real needs of artificial radioactive tracers in hydrology. To identify the fields for which artificial radioactive tracers are useful as well as those in which they can be substituted by other tracers. To discuss the strategy to be adopted to overcome the difficulties derived from the restrictions on the use of radioactive tracers in hydrology. The meeting was held at IAEA Headquarters from 19 to 22 March 1990, and was attended by 30 participants from 15 Member States. The conclusions and recommendations are that the use of artificial radioactive tracers should be restricted to cases where other tracers cannot be used or do not provide the same quality of information. Tritium, iodine-131, bromine-82, chromium-51 in the form of Cr-EDTA, technetium-99m obtained from 99Mo-generators and gold-198 as an adsorbable tracer are, practically, the only radionuclides used for water tracing. The use of other radionuclides for this purpose does not appear to be necessary, possible and/or convenient. Refs, figs and tabs

  2. Preliminary analysis of the induced structural radioactivity inventory of the base-case aqueous accelerator transmutation of waste reactor concept

    International Nuclear Information System (INIS)

    The purpose of the Los Alamos National Laboratory Accelerator Transmutation of (Nuclear) Waste (ATW) project is the substantial reduction in volume of long-lived high-level radioactive waste of the US in a safe and energy-efficient manner. An evaluation of the ATW concept has four aspects: material balance, energy balance, performance, and cost. An evaluation of the material balance compares the amount of long-lived high-level waste transmuted with the amount and type, of waste created in the process. One component of the material balance is the activation of structural materials over the lifetime of the transmutation reactor. A preliminary radioactivity and radioactive mass balance analysis has been performed on four structure regions of the reaction chamber: the tungsten target, the lead annulus, six tubing materials carrying the actinide slurry, and five reaction vessel structural materials. The amount of radioactive material remaining after a 100-yr cooling period for the base-case ATW was found to be 338 kg of radionuclides. The bulk of this material (313 kg) was generated in the zirconium-niobium (Zr-Nb) actinide tubing material. Replacement of the Zr-Nb tubing material with one of the alternative tubing materials analyzed would significantly reduce the short- and long-term radioactive mass produced. The alternative vessel material Al-6061 alloys, Tenelon, HT-9, and 2 1/4 Cr-1 Mo and the alternative actinide tubing materials Al-6061 alloy, carbon-carbon matrix, silicon carbide, and Ti-6 Al-4 V qualify for shallow land burial. Alternative disposal options for the base-case structural material Type 304L stainless steel and the actinide tubing material Zr-Nb will need to be considered as neither qualifies for shallow land burial

  3. Assessment of crevice corrosion and hydrogen-induced stress-corrosion cracks in titanium-carbon steel composite overpack for geological disposal of high-level radioactive waste

    International Nuclear Information System (INIS)

    Overpacks for high-level radioactive waste (HLW) must be reliable for geological disposal for as long as 1000-10 000 years. From a study of parameters such as the critical potential for initiation of crevice corrosion, ER,CREV and the free corrosion potential Esp in neutral aqueous environments it is concluded that composite overpacks composed of a corrosion resistant Ti alloy (Ti-0.06 Pd, or Ti-Gr.17) outer layer and a carbon steel inner layer should never be subject to crevice corrosion and hydrogen-induced stress corrosion cracking when stored deep underground environments. Hydrogen-induced stress corrosion cracking has been shown not to occur in alloys exposed to conditions of disposal based according to results based on accelerated constant current tests and constant load tests. (authors)

  4. Processing Semblances Induced through Inter-Postsynaptic Functional LINKs, Presumed Biological Parallels of K-Lines Proposed for Building Artificial Intelligence.

    Science.gov (United States)

    Vadakkan, Kunjumon I

    2011-01-01

    The internal sensation of memory, which is available only to the owner of an individual nervous system, is difficult to analyze for its basic elements of operation. We hypothesize that associative learning induces the formation of functional LINK between the postsynapses. During memory retrieval, the activation of either postsynapse re-activates the functional LINK evoking a semblance of sensory activity arriving at its opposite postsynapse, nature of which defines the basic unit of internal sensation - namely, the semblion. In neuronal networks that undergo continuous oscillatory activity at certain levels of their organization re-activation of functional LINKs is expected to induce semblions, enabling the system to continuously learn, self-organize, and demonstrate instantiation, features that can be utilized for developing artificial intelligence (AI). This paper also explains suitability of the inter-postsynaptic functional LINKs to meet the expectations of Minsky's K-lines, basic elements of a memory theory generated to develop AI and methods to replicate semblances outside the nervous system. PMID:21845180

  5. Resistance of Mutants of Sweet Orange Induced by Gamma-rays to Citrus Canker (Xanthomonas citri subsp. citri) Under Artificial Inoculation

    International Nuclear Information System (INIS)

    The sweet orange holds great economic and social importance for Brazil, but it is susceptible to citrus canker as is the majority of citrus species. In cases of high incidence, this disease caused by the bacterium Xanthomonas citri subsp. citri can result in great economic damage. More resistant cultivars are the best long-term solution for management of citrus canker and one of the approaches can be the production of mutant plants. In a previous work, several induced mutant clones of sweet orange cv. Pera were selected. They showed a lower intensity of symptoms of citrus canker in leaves and fruits in evaluations under natural incidence of the disease, in the field. The objective of this study is to assess the resistance to citrus canker of six mutant clones of cultivar Pera and control plants (three different varieties), in experiments of artificial inoculation. The parameters evaluated were: incubation period, diameter of the lesions and area under the disease progress curve (AUDPC), in evaluations every 15 days, until the 147th day. Only the clones 9-1, 9-2 and 9-3 showed lower incidence of disease, represented by the longest period of incubation of the disease, smaller diameter of lesion and lower AUDPC, using average data of the three experiments. This study is one of the first reports of success in citrus-induced mutations aimed to obtaining greater resistance to diseases. (author)

  6. Resistance of mutants of sweet orange induced by gamma-rays to citrus canker (Xanthomonas citri subsp. citri) under artificial inoculation

    International Nuclear Information System (INIS)

    The sweet oranges have great economic and social importance for Brazil. However, it is susceptible to citrus canker as the majority of citrus species. This disease is caused by Xanthomonas citri subsp. citri, bacteria that in case of high incidence can result in great economic damage. More resistant cultivars are the best long-term solution for management of citrus canker and one of the approaches can be the production of mutant plants. In a previous work, several induced mutant clones of sweet orange cv. Pera were selected. They showed lower intensity of symptoms of citrus canker in leaves and fruits in evaluations under natural incidence of the disease, in the field. The objective of this study is to assess the resistance to citrus canker of six mutant clones of cultivar Pera and control plants (three different varieties), in experiments of artificial inoculation. The parameters evaluated were: incubation period, diameter of the lesions and area under the disease progress curve (AUDPC), in evaluations every 15 days, until the 147th day. Only the clones 9-1, 9-2 and 9-3 showed lower incidence of disease, represented by the longest period of incubation of the disease, smaller diameter of lesion and lower AUDPC, in all experiment and using average data of the three experiments. This study is one of the first reports of success in citrus induced mutations aimed to obtaining greater resistance to diseases. (author)

  7. Probabilistic siting analysis of nuclear power plants emphasizing atmospheric dispersion of radioactive releases and radiation-induced health effects

    International Nuclear Information System (INIS)

    A presentation is made of probabilistic evaluation schemes for nuclear power plant siting. Effects on health attributable to ionizing radiation are reviewed, for the purpose of assessment of the numbers of the most important health effect cases in light-water reactor accidents. The atmospheric dispersion of radioactive releases from nuclear power plants is discussed, and there is presented an environmental consequence assessment model in which the radioactive releases and atmospheric dispersion of the releases are treated by the application of probabilistic methods. In the model, the environmental effects arising from exposure to radiation are expressed as cumulative probability distributions and expectation values. The probabilistic environmental consequence assessment model has been applied to nuclear power plant site evaluation, including risk-benefit and cost-benefit analyses, and the comparison of various alternative sites. (author)

  8. A case of propylthiouracil-induced antineutrophilic cytoplasmic antibody-positive vasculitis successfully treated with radioactive iodine

    Directory of Open Access Journals (Sweden)

    C. Bes

    2013-07-01

    Full Text Available Antineutrophilic cytoplasmic antibody (ANCA associated vasculitis is one of the rare complications of propylthiouracil treatment. Having a variable clinical spectrum, it may be presented with both skin limited vasculitis and life-threatening systemic vasculitis. In this study, we present a case that developed ANCA-positive vasculitis with skin and kidney involvement (hematuria and proteinuria six months after propylthiouracil treatment was initiated for toxic nodular goiter. Proteinuria recovered dramatically subsequent to radioactive iodine treatment following ceasing the drug.

  9. Changes induced in Biomphalaria glabrata (Say, 1818) following trials for artificial stimulation of its internal defense system

    Scientific Electronic Library Online (English)

    Carine Machado, Azevedo; Claudia Cunha, Borges; Zilton A, Andrade.

    2006-10-01

    Full Text Available Biomphalaria glabrata can react through different pathways to Schistosoma mansoni miracidium penetration, according to the degree of resistance/susceptibility presented by different snail strains, which is a genetically determined character, resistance being the dominant feature. However, it has bee [...] n observed that previous susceptible snail strain may change its reactive behavior along the course of infection, exhibiting later a pattern of cercarial shedding and histopatopathological picture compatible with high resistance. Such observation suggests the possibility of B. glabrata to develop a sort of adaptative immunity face a schistosome infection. To explore on this aspect, the present investigation looked for the behavior of S. mansoni infection in B. glabrata previously subjected to different means of artificial stimulation of its internal defense system. Snails previously inoculated with irradiated miracídia (Group I); treated with S. mansoni antigens (Group II) or with a non-related parasite antigen (Group III) were challenged with 20 viable S. mansoni miracidia, and later looked for cercarial shedding and histopathologic changes at different times from exposition. Nodules of hemocyte accumulations were found at the site of antigen injection. These nodules resembled solid granulomas, and were larger and more frequent in snails injected with S. mansoni products as compared to those injected with Capillaria hepatica. However, the presence of such granulomas did not avoid the S. mansoni challenge infection from developing in a similar way as that seen in controls. The data are indicative that hemocytes are able to proliferate locally when stimulated, such capacity also remaining localized, not being shared by the population of hemocytes located elsewhere within the snail body.

  10. Predicting typhoon-induced storm surge tide with a two-dimensional hydrodynamic model and artificial neural network model

    Science.gov (United States)

    Chen, W.-B.; Liu, W.-C.; Hsu, M.-H.

    2012-12-01

    Precise predictions of storm surges during typhoon events have the necessity for disaster prevention in coastal seas. This paper explores an artificial neural network (ANN) model, including the back propagation neural network (BPNN) and adaptive neuro-fuzzy inference system (ANFIS) algorithms used to correct poor calculations with a two-dimensional hydrodynamic model in predicting storm surge height during typhoon events. The two-dimensional model has a fine horizontal resolution and considers the interaction between storm surges and astronomical tides, which can be applied for describing the complicated physical properties of storm surges along the east coast of Taiwan. The model is driven by the tidal elevation at the open boundaries using a global ocean tidal model and is forced by the meteorological conditions using a cyclone model. The simulated results of the hydrodynamic model indicate that this model fails to predict storm surge height during the model calibration and verification phases as typhoons approached the east coast of Taiwan. The BPNN model can reproduce the astronomical tide level but fails to modify the prediction of the storm surge tide level. The ANFIS model satisfactorily predicts both the astronomical tide level and the storm surge height during the training and verification phases and exhibits the lowest values of mean absolute error and root-mean-square error compared to the simulated results at the different stations using the hydrodynamic model and the BPNN model. Comparison results showed that the ANFIS techniques could be successfully applied in predicting water levels along the east coastal of Taiwan during typhoon events.

  11. Predicting typhoon-induced storm surge tide with a two-dimensional hydrodynamic model and artificial neural network model

    Directory of Open Access Journals (Sweden)

    W.-B. Chen

    2012-12-01

    Full Text Available Precise predictions of storm surges during typhoon events have the necessity for disaster prevention in coastal seas. This paper explores an artificial neural network (ANN model, including the back propagation neural network (BPNN and adaptive neuro-fuzzy inference system (ANFIS algorithms used to correct poor calculations with a two-dimensional hydrodynamic model in predicting storm surge height during typhoon events. The two-dimensional model has a fine horizontal resolution and considers the interaction between storm surges and astronomical tides, which can be applied for describing the complicated physical properties of storm surges along the east coast of Taiwan. The model is driven by the tidal elevation at the open boundaries using a global ocean tidal model and is forced by the meteorological conditions using a cyclone model. The simulated results of the hydrodynamic model indicate that this model fails to predict storm surge height during the model calibration and verification phases as typhoons approached the east coast of Taiwan. The BPNN model can reproduce the astronomical tide level but fails to modify the prediction of the storm surge tide level. The ANFIS model satisfactorily predicts both the astronomical tide level and the storm surge height during the training and verification phases and exhibits the lowest values of mean absolute error and root-mean-square error compared to the simulated results at the different stations using the hydrodynamic model and the BPNN model. Comparison results showed that the ANFIS techniques could be successfully applied in predicting water levels along the east coastal of Taiwan during typhoon events.

  12. Psychologically induced cooling of a specific body part caused by the illusory ownership of an artificial counterpart.

    OpenAIRE

    Moseley, GL; Olthof, N; Venema, A.; Don, S; Wijers, M; Gallace, A.; Spence, C

    2008-01-01

    The sense of body ownership represents a fundamental aspect of our self-awareness, but is disrupted in many neurological, psychiatric, and psychological conditions that are also characterized by disruption of skin temperature regulation, sometimes in a single limb. We hypothesized that skin temperature in a specific limb could be disrupted by psychologically disrupting the sense of ownership of that limb. In six separate experiments, and by using an established protocol to induce the rubber h...

  13. Artificial intelligence

    International Nuclear Information System (INIS)

    A vivid example of the growing need for frontier physics experiments to make use of frontier technology is in the field of artificial intelligence and related themes. This was reflected in the second international workshop on 'Software Engineering, Artificial Intelligence and Expert Systems in High Energy and Nuclear Physics' which took place from 13-18 January at France Telecom's Agelonde site at La Londe des Maures, Provence. It was the second in a series, the first having been held at Lyon in 1990

  14. Forest decline through radioactivity

    International Nuclear Information System (INIS)

    Is more serious damage of forest observed in the vicinity of nuclear reactors. How are those decline patterns to be explained. Does the combined effect of radioactivity and different air pollutants (such as nitrogen oxides, sulfur dioxide, oxidants etc.) have an influence in the decline of the forest. In what way do synergisms, i.e. mutually enhanced effects, participate. How does natural and artificial radioactivity affect the chemistry of air in the polluted atmosphere. What does this mean for the extension of nuclear energy, especially for the reprocessing plant planned. Damage in the forests near nuclear and industrial plants was mapped and the resulting hypotheses on possible emittors were statistically verified. Quantitative calculations as to the connection between nuclear energy and forest decline were carried through: they demand action. (orig./HP)

  15. Spin-valley filtering in strained graphene structures with artificially induced carrier mass and spin-orbit coupling.

    Science.gov (United States)

    Gruji?, Marko M; Tadi?, Milan Ž; Peeters, François M

    2014-07-25

    The interplay of massive electrons with spin-orbit coupling in bulk graphene results in a spin-valley dependent gap. Thus, a barrier with such properties can act as a filter, transmitting only opposite spins from opposite valleys. In this Letter we show that a strain induced pseudomagnetic field in such a barrier will enforce opposite cyclotron trajectories for the filtered valleys, leading to their spatial separation. Since spin is coupled to the valley in the filtered states, this also leads to spin separation, demonstrating a spin-valley filtering effect. The filtering behavior is found to be controllable by electrical gating as well as by strain. PMID:25105639

  16. Artificial Laboratories

    OpenAIRE

    Lacy, Mark

    1989-01-01

    An artificial laboratory is a hypothetical computing environment of the future that would integrate mathematical and statistical tools with AI methods to assist in computer modeling and simulation. An integrated approach of this kind has great potential for accelerating the rate of scientific discovery.

  17. Thermal neutron induced charged particle reactions in radioactive targets of $^{37}$Ar, $^{109}$Cd, $^{125}$Xe, $^{127}$Xe, and $^{132}$Cs

    CERN Document Server

    Asghar, M; Hagberg, E; Jonson, B; Tidemand-Petersson, P

    1978-01-01

    Thermal neutron induced charged particle reactions in a radioactive target of /sup 37/Ar have been studied. Upper limits of the cross- sections for the (n, alpha ) reaction in radioactive targets of /sup 109/Cd, /sup 125,127/Xe, and /sup 132/Cs have been obtained. The isotopically pure targets were produced at the ISOLDE facility at CERN and irradiated with thermal neutrons at the high flux reactor of the Institute Laue-Langevin in Grenoble. Charged particles from (n, p) and (n, alpha ) reactions in /sup 37/Ar were observed with cross-sections of 69+or-14 b and 1970+or-330b, respectively. The Q-values for these reactions were determined to be 1600+or-12 keV and 4630+or-7 keV, in agreement with existing mass data. The branching ratio Gamma /sub alpha // Gamma /sub p/ of the /sup 37/Ar capturing state was found to be 28.5+or-2.7. An upper limit of the cross-section for the (n, gamma alpha ) reaction in /sup 37/Ar was obtained. (18 refs).

  18. Evaluation of genetic variability for heading date and height in triticale obtained by induced mutations and artificial crosses

    International Nuclear Information System (INIS)

    The adjustment of adaptive characters such as heading date and height, allows one to arrange successive cultures and to apply efficient agronomic techniques, resulting in productivity increase. Methods that increase genetic variability have great significance in plant breeding, once they amplify the opportunities for selecting superior genotypes. The aim of this study was to evaluate the effect of induced mutations and reciprocal crosses in families segregating for heading date and height and to analyze the correlation between these characters. The populations were obtained from reciprocal crosses and induced mutation with gamma radiation. In the latter, radiation dosages of 0, 5, 10, 20, 40 kR were obtained from exposition to Cobalt - 60. Changes in the mean and variance in two triticale genotypes Triticale BR4 e EMBRAPAI8, were analyzed. The results obtained indicated families with wide segregation patterns for heading date and height and also suggested the possibility to identify families with distinct values compared to the control population for both characters and both genotypes. There was a tendency to reductions in height and increases in heading date for the families evaluated. However, there was not an expressive correlation between heading date and height for the majority of the treatments, therefore allowing the breeder to select plant types adapted to the environment of cultivation. (author)

  19. Radioactivity and nuclear energy

    International Nuclear Information System (INIS)

    The terms radioactivity and nuclear energy, which have become words causing irritation in the political sphere, actually represent nothing but a large potential for innovative exploitation of natural resources. The contributions to this publication of the Karlsruhe Research Center examine more closely three major aspects of radioactivity and nuclear energy. The first paper highlights steps in the history of the discovery of radioactivity in the natural environment and presents the state of the art in health physics and research into the effects of exposure of the population to natural or artificial radionuclides. Following contributions focus on: Radiochemical methods applied in the medical sciences (diagnostic methods and devices, therapy). Nuclear energy and electricity generation, and the related safety policies, are an important subject. In this context, the approaches and pathways taken in the field of nuclear science and technology are reported and discussed from the angle of nuclear safety science, and current trends are shown in the elaboration of advanced safety standards relating to nuclear power plant operation and ultimate disposal of radioactive wastes. Finally, beneficial aspects of nuclear energy in the context of a sustainable energy policy are emphasized. In particular, the credentials of nuclear energy in the process of building an energy economy based on a balanced energy mix which combines economic and ecologic advantages are shown. (orig./CB)

  20. Reliability assessment of high energy particle induced radioactivity calculation code DCHAIN-SP 2001 by analysis of integral activation experiments with 14 MeV neutrons

    International Nuclear Information System (INIS)

    Reliability assessment for the high energy particle induced radioactivity calculation code DCHAIN-SP 2001 was carried out through analysis of integral activation experiments with 14-MeV neutrons aiming at validating the cross section and decay data revised from previous version. The following three kinds of experiments conducted at the D-T neutron source facility, FNS, in JAERI were employed: (1) the decay gamma-ray measurement experiment for fusion reactor materials, (2) the decay heat measurement experiment for 32 fusion reactor materials, and (3) the integral activation experiment on mercury. It was found that the calculations with DCHAIN-SP 2001 predicted the experimental data for (1) - (3) within several tens of percent. It was concluded that the cross section data below 20 MeV and the associated decay data as well as the calculation algorithm for solving the Beteman equation that was the master equation of DCHAIN-SP were adequate. (author)

  1. Reliability assessment of high energy particle induced radioactivity calculation code DCHAIN-SP 2001 by analysis of integral activation experiments with 14 MeV neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Kai, Tetsuya; Maekawa, Fujio; Kasugai, Yoshimi; Takada, Hiroshi; Ikeda, Yujiro [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment; Kosako, Kazuaki [Sumitomo Atomic Energy Industries, Ltd., Tokyo (Japan)

    2002-03-01

    Reliability assessment for the high energy particle induced radioactivity calculation code DCHAIN-SP 2001 was carried out through analysis of integral activation experiments with 14-MeV neutrons aiming at validating the cross section and decay data revised from previous version. The following three kinds of experiments conducted at the D-T neutron source facility, FNS, in JAERI were employed: (1) the decay gamma-ray measurement experiment for fusion reactor materials, (2) the decay heat measurement experiment for 32 fusion reactor materials, and (3) the integral activation experiment on mercury. It was found that the calculations with DCHAIN-SP 2001 predicted the experimental data for (1) - (3) within several tens of percent. It was concluded that the cross section data below 20 MeV and the associated decay data as well as the calculation algorithm for solving the Beteman equation that was the master equation of DCHAIN-SP were adequate. (author)

  2. Measurements of D-T neutron induced radioactivity in plasma-facing materials and their role in qualification of activation cross-section libraries and codes

    International Nuclear Information System (INIS)

    USDOE/JAERI collaborative program on induced radioactivity measurements has been spread over last five years and has covered, among others, a large number of plasma facing materials of interest to D-T fusion reactors, including ITER and DEMO. The experiments have consisted of irradiation of high purity material samples in a range of neutron energy spectra in simulated fusion environments of prototypical blanket assemblies driven by D-T neutrons at FNS/JAERI. A typical sample measured 10 mm in diameter by 1 mm thickness, and the neutron fluence ranged from ?1010 n/cm2 to ?1014 n/cm2, over an irradiation period of 30 m and 10 h. The irradiated samples were then cooled for varying times, from ?10 m to ?3 weeks, and their activity was derived by counting associated ?-rays with intrinsic germanium detectors

  3. Radioactive Material

    CERN Multimedia

    2004-01-01

    The Radiation Protection Group of the Safety Commission is responsible for shipping of radioactive material from CERN to any external institute or organisation. The RP group is equally responsible for the reception of radioactive material shipped to any of the CERN sites. Anyone who needs to ship from or import into CERN radioactive material must contact the Radioactive Shipping Service of the RP group in advance. Instructions are available at: http://cern.ch/rp-shipping or in the Radiation Protection Procedure PRP13: https://edms.cern.ch/document/346823 Radiation Protection Group

  4. Fast identification of biominerals by means of stand-off laser-induced breakdown spectroscopy using linear discriminant analysis and artificial neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Vitkova, Gabriela [Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic); Novotny, Karel, E-mail: codl@sci.muni.cz [Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic); Prokes, Lubomir [Department of Chemistry, Faculty of Science, Masaryk University, Kotlarska 2, 611 37 Brno (Czech Republic); Hrdlicka, Ales [Central European Institute of Technology, CEITEC MU, Masaryk University (Czech Republic); Kaiser, Jozef [Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technicka 2896/2, 616 69 Brno (Czech Republic); X-ray micro CT and nano CT research group, CEITEC-Central European Institute of Technology, Brno University of Technology, Technicka 2896/2, 616 69 Brno (Czech Republic); Novotny, Jan [X-ray micro CT and nano CT research group, CEITEC-Central European Institute of Technology, Brno University of Technology, Technicka 2896/2, 616 69 Brno (Czech Republic); Malina, Radomir; Prochazka, David [Institute of Physical Engineering, Faculty of Mechanical Engineering, Brno University of Technology, Technicka 2896/2, 616 69 Brno (Czech Republic)

    2012-07-15

    The goal of this paper is to compare two selected statistical techniques used for identification of archeological materials merely on the base of their spectra obtained by stand-off laser-induced breakdown spectroscopy (stand-off LIBS). Data processing using linear discriminant analysis (LDA) and artificial neural networks (ANN) were applied on spectra of 18 different samples, some of them archeological and some recent, containing 7 types of material (i.e. shells, mortar, bricks, soil pellets, ceramic, teeth and bones). As the input data PCA scores were taken. The intended aim of this work is to create a database for simple and fast identification of archeological or paleontological materials in situ. This approach can speed up and simplify the sampling process during archeological excavations that nowadays tend to be quite damaging and time-consuming. - Highlights: Black-Right-Pointing-Pointer We use statistical techniques for identification of archeological materials. Black-Right-Pointing-Pointer Input data for LDA and ANN are PC scores counted from stand-off LIBS spectra. Black-Right-Pointing-Pointer The method used for identification of archeological materials provides good results. Black-Right-Pointing-Pointer After recording more spectra we can get useful tool for rapid analysis in situ.

  5. Fast identification of biominerals by means of stand-off laser?induced breakdown spectroscopy using linear discriminant analysis and artificial neural networks

    International Nuclear Information System (INIS)

    The goal of this paper is to compare two selected statistical techniques used for identification of archeological materials merely on the base of their spectra obtained by stand-off laser-induced breakdown spectroscopy (stand-off LIBS). Data processing using linear discriminant analysis (LDA) and artificial neural networks (ANN) were applied on spectra of 18 different samples, some of them archeological and some recent, containing 7 types of material (i.e. shells, mortar, bricks, soil pellets, ceramic, teeth and bones). As the input data PCA scores were taken. The intended aim of this work is to create a database for simple and fast identification of archeological or paleontological materials in situ. This approach can speed up and simplify the sampling process during archeological excavations that nowadays tend to be quite damaging and time-consuming. - Highlights: ? We use statistical techniques for identification of archeological materials. ? Input data for LDA and ANN are PC scores counted from stand-off LIBS spectra. ? The method used for identification of archeological materials provides good results. ? After recording more spectra we can get useful tool for rapid analysis in situ.

  6. The effect of artificially induced hyperglycemia on the radiation response of the Lewis lung and EMT6 tumor models

    International Nuclear Information System (INIS)

    The effect of hyperglycemia, induced by administration of glucose, on the radiation response of the Lewis lung and EMT6 tumor models has been evaluated. Neither acute (single i.p. injection of 8mg/glucose) nor chronic (multiple i.p. injections of 6mg/g glucose plus glucose in the water bottles) administrations of glucose increased the radiation response of either tumor. A combination of a single i.p. injection of glucose and a reduction of the O2 content of the inspired gas to 10 per cent did by itself reduce cell survival by 55-75% in the EMT6 and 80-90% in the Lewis lung carcinoma. However, this treatment had little effect on the shape of the radiation dose-response curve, and simply gave rise to a parallel shift of the survival curve, indicating that this treatment had little or no specificity for hypoxic cells. (author)

  7. Measurement and simulation of induced radioactivity and remanent dose rates at the CERN-EU high energy reference field facility

    International Nuclear Information System (INIS)

    Full text: Various samples of materials typically used at high energy accelerators were irradiated by the stray radiation field produced by interactions of high energy hadrons in a copper target. Specific activities and remanent dose rates were measured at different cooling times and compared to results of detailed Monte-Carlo simulations using the FLUKA code. For the calculation of remanent dose rates, a new approach has been developed and applied to the experimental setup. It is based on an explicit calculation of isotope production followed by a complete transport of the photons, electrons, and positrons from the radioactive decays to the point of interest. Finally, examples are given for applications of this method to the estimation of remanent dose rates at the large hadron collider, especially the two beam cleaning insertions. (author)

  8. Artificial intelligence

    OpenAIRE

    Shapovalenko, A.

    2013-01-01

    Technology of artificial intelligence will soon be able to help ensure the safety of your family, protecting it from the threat of international and domestic burglaries. In the USA the Department of Security also implements special software in its monitoring system, which scans phone calls and other messages. These programs can rapidly process large volumes of data and are even able to distinguish between a normal conversation from a potential threat. The old security system simply relied on ...

  9. The environmental assessment of radioactive materials using yeast DNA microarray. Genomic profiling of thorium-induced changes in yeast cells

    International Nuclear Information System (INIS)

    We evaluated the toxicity of thorium (nitrate) in the environment by using a Saccharomyces cerevisiae DNA microarray, and present the genome-wide profile of induced yeast genes. A total of 185 out of about 6,000 genes spotted on the microarray chip were induced by thorium. Functional analysis of these genes revealed that gene categories in 'C-compound and carbohydrate metabolism', 'Energy', 'Lipid fatty acid and isoprenoid metabolism' and 'Cell rescue, defense and virulence' were the most highly induced by thorium treatment. Moreover, localization analysis of these genes revealed that gene categories in 'Extracellular', 'Cell wall', 'Plasma membrane' and 'Cell periphery' were also highly induced by thorium treatment. In the categories of 'Cell rescue, defense and virulence', genes related to oxidative stress were induced. In the categories of 'C-compound and carbohydrate metabolism' and 'Energy', genes relate to glycogen metabolism were observed. In the categories of 'Extracellular' and 'Cell wall', genes related to cell component were detected while genes related to sugar transporters were detected in the categories of Plasma membrane'. These results provide the first insight into the effect of thorium on yeast cells. (author)

  10. Reduction of radioactivity produced by nuclear explosives

    International Nuclear Information System (INIS)

    Four main sources contribute to the radioactivity produced by a nuclear explosive: 1. Fission products from the nuclear explosive, 2. Fusion products from the nuclear explosive, 3. Induced radioactivity in the nuclear explosive, 4. Induced radioactivity in the environment. This paper will summarize some of the work done at the Lawrence Radiation Laboratory at Livermore to reduce the radioactivity from these sources to levels acceptable for peaceful applications. Although it is theoretically possible to have no radioactivity produced by nuclear explosives, this goal has not been achieved

  11. Environmental radioactivity and radiation exposure

    International Nuclear Information System (INIS)

    In 1977 population exposure in the Federal Republic of Germany has not changed as compared to the previous years. The main share of the total exposure, nearly two thirds, is attributed to natural radioactive substances and cosmic radiation. The largest part (around 85%) of the artificial radiation exposure is caused by X-ray diagnostics. In comparison to this, radiation exposure from application of ionizing radiation in medical therapy, use of radioactive material in research and technology, or from nuclear facilities is small. As in the years before, population exposure caused by nuclear power plants and other nuclear facilities is distinctly less than 1% of the natural radiation exposure. This is also true for the average radiation exposure within a radius of 3 km around nuclear facilities. On the whole, the report makes clear that the total amount of artificial population exposure will substantially decrease only if one succeeds in reducing the high contribution to the radiation exposure caused by medical measures. (orig.)

  12. Ambient radioactivity levels and radiation doses. Annual report 2011

    International Nuclear Information System (INIS)

    The annual report 2011 on ambient radioactivity levels and radiation doses covers the following issues: Part A: Natural environmental radioactivity, artificial radioactivity in the environment, occupational radiation exposure, radiation exposure from medical applications, the handling of radioactive materials and sources of ionizing radiation, non-ionizing radiation. Part B; Current data and their evaluation: Natural environmental radioactivity, artificial radioactivity in the environment, occupational radiation exposure, radiation exposure from medical applications, the handling of radioactive materials and sources of ionizing radiation, non-ionizing radiation. The Appendix includes Explanations of terms, radiation doses and related units, external and internal radiation exposure, stochastic and deterministic radiation effects, genetic radiation effects, induction of malignant neoplasm, risk assessment, physical units and glossary, laws, ordinances, guidelines, recommendations and other regulations concerning radiation protection, list of selected radionuclides.

  13. Ambient radioactivity levels and radiation doses. Annual report 2010

    International Nuclear Information System (INIS)

    The annual report 2010 on ambient radioactivity levels and radiation doses covers the following topics in two parts: Part (A) General information: (I) Natural environmental radioactivity. (II) Artificial radioactivity in the environment. (III) Occupational radiation exposure. (IV) Radiation exposures from medical applications. (V) The handling of radioactive materials and sources of ionizing radiation. (VI) Non-ionizing radiation. Part (B) Current data and their evaluation: (I) Natural environmental radioactivity. (II) Artificial radioactivity in the environment. (III) Occupational radiation exposure. (IV) Radiation exposures from medical applications. (V) The handling of radioactive materials and sources of ionizing radiation. (VI) Non-ionizing radiation (electromagnetic fields, optical radiation). The Annex covers explanation on terms, physical units, glossary, list of abbreviations, radiation protection laws, regulations etc. and a list of selected radionuclides.

  14. Radioactive Wastes.

    Science.gov (United States)

    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. PMID:26420096

  15. Radioactive waste management

    International Nuclear Information System (INIS)

    In this chapter the radioactive waste management is presented. This chapter consists of the following parts: Radioactive decay and radioactivity; Effect of ionizing radiation on human body; Establishment of radioactive wastes and their categorization; Radioactive waste management (Ways of dealing with radioactive waste and Storage and permanent disposal of radioactive waste; Nuclear fuel cycle and production of radioactive waste.

  16. First artificial radionuclides for Czechoslovakia after Word War II. Pt. 1

    International Nuclear Information System (INIS)

    This first contribution in the 2-part series describes the following topics: Discovery of artificial radioactivity and first artificial radionuclides; Czechoslovak reflection of the development over the world; Opportunities for obtaining artificial radioisotopes from the USA; Response to the US offer by Czechoslovak physicians; and Steps taken by the Ministry of Health. (orig.)

  17. Artificial hand:

    OpenAIRE

    Wisse, M.; Wilbers, F (Freerk); C. Meijneke

    2011-01-01

    Artificial hand (1) suitable for robotic applications or as a prosthesis, comprising a frame (2) with a thumb (3) and at least two fingers (4,5), and having a motor drive (6) for adjusting the thumb and the fingers with respect to the frame, wherein the motor drive has a housing (7) and an axle (8) which is rotatably positioned within the housing, and wherein the housing is mounted in a first bearing (9') supported by the frame to enable that the housing may rotate with regard to the frame, a...

  18. Radioactivity Monitoring of the Irish Environment 2008

    International Nuclear Information System (INIS)

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland (RPII) during 2008. The RPII has routinely monitored levels of radioactivity in the environment since 1982 and this is the latest in the RPII's series of environmental monitoring reports. The RPII reviews and updates its environmental programme annually so as to ensure it remains relevant and continues to focus on the most important sources of radioactivity in the environment. The principal aims of the RPII's monitoring programme are; to assess the level of radioactivity to which the Irish population is exposed as a result of radioactivity in the environment; to study trends and establish the geographical distribution of contaminating radionuclides so as to better understand the long term behaviour of artificial radioactivity in the food chain and the environment; to ensure that any increase in radiation levels resulting from an accidental release of radioactivity to the environment is detected and assessed rapidly. During 2008 radioactivity was measured in a wide range of foods and environmental materials including: air, water, milk, seafood, foodstuffs and complete meals. The most significant source of artificial radioactivity in the Irish marine environment is the discharge of low level liquid radioactive waste from the Sellafield Nuclear Fuel Reprocessing Plant on the north east coast of England. In order to assess the exposure arising from the source extensive sampling of fish and shellfish landed at ports along the north east coast of Ireland is undertaken. The most exposed group of individuals to discharges from Sellafield have been identified as commercial oyster and mussel farmers working along the north east coastline and their families. Manmade radioactivity is also present in the terrestrial environment due primarily to residual global fallout arising primarily from atmospheric testing of nuclear weapons in the 1950s and 1960s and releases from past nuclear accidents such as Chernobyl. Milk, because it is an important foodstuff for infants and children and is known to concentrate long lived radionuclides such as caesium-137 and strontium-90, is an important indicator of levels of artificial radioactivity in the terrestrial food chain. The estimated dose due to strontium-90 activity in milk was estimated to be 0.55 ?Sv for 2008. This was for the most exposed group, assessed to be infants, children under the age of one year. It is very small compared to the background radiation. Radioactivity measurements on other foodstuffs confirm the levels of artificial radioactivity in the Irish food-chain remain very low and that Irish foodstuffs are free from harmful levels of radioactivity. The RPII monitors radioactivity in drinking water supplies in rotation so that major supplies from each county are sampled at least once every four years. During 2008 supplies from Carlow, Cavan, Clare, Cork, Donegal and Dublin were tested. Drinking water samples are assessed for compliance with the radioactivity standards set out in the Drinking Water Directive. All drinking water samples tested during 2008 were found to be in compliance with the radioactivity standards set out in the Drinking Water Directive. The RPII programme also monitors airborne radioactivity through its network of on- and off-line samplers. External gamma dose rates are also monitored. No exceptional activity was detected in outdoor air during 2008. The levels were consistent with those recorded in previous years. For 2008 the average annual dose from inhalation of caesium-137 was estimated at 8.0 x 10?? ?Sv. The data presented in this report confirm that while the levels of artificial radioactivity in the Irish environment are detectable they are low and are continuing to decrease. They do not pose a significant risk to the human health of the Irish population. Activity concentrations of radionuclides in airborne particulates were low and consistent with measurements made in recent years. Radioactivity level

  19. Walter Russell's concepts as the basis for an alternative view on radioactivity induced oxygen-ozone depletion and food chain pollution; and as the basis for alternative fuels, materials, energy production, and radioactive waste cleanup

    International Nuclear Information System (INIS)

    The following topics with supporting data will be presented: The transmutation of atmospheric nitrogen into carbon 14 and tritium via radioactivity as a source of omnipresent food and water pollution, and the possible correlation of oxygen transmutation into carbon 14 and tritium by the same mechanisms as well as into sulfur. Walter Russell's four pole field dual polarity control as a basis for transmutation will be discussed with reference to past and contemporary results of experimentation on this basis. Extension of the concepts into free hydrogen energy fuel, nitrogen fertilizers, other materials production,and transmutation of radioactive wastes into non radioactive elements will be discussed

  20. Protection of metallurgical production from radioactive contamination

    International Nuclear Information System (INIS)

    Systems to detect any ionising radiation source in scrap are routinely installed at the input to metallurgical plants. Tracking by means of hand instruments enables removing various radioactive materials from scrap. Materials can be contaminated by natural radionuclides (e.g. materials of the NORM type) and by artificial radionuclides (e.g. 60Co in steel products). If radioactivity is detected, the material is disposed of in compliance with applicable legislation

  1. Forest decline, natural and technically generated radioactivity

    International Nuclear Information System (INIS)

    The question investigated is whether the radioactive rare gases emanating from nuclear plants are causative or participate in the triggering of forest disease. For one thing, a chemical reaction could be responsible for such an effect exerted by these artificial radioactive effluents. However, a calculation shows the concentration of radionuclides, respectively, in this case, their decomposition products, to be by many orders of magnitude smaller than other constituents in air; so a chemical reaction of this kind may be excluded. For the other part, rare gases might contribute to forest damage by their radioactive decomposition and late physical, chemical, and biological effects. In this connection, a detailed analysis is made of the comparability of natural radioactivity with radioactivity generated by nuclear plants. A possible contribution towards the total stress situation of forests (chemical air pollution, natural radioactivity, artificially produced radioactive rare gases, weather conditions and conditions arising from forest management and the like) would amount to a proportion smaller than 1/1000 considering natural radioactivity as a possible stress factor only. (orig.)

  2. Subject: Radioactivity

    International Nuclear Information System (INIS)

    Having dealt with the history of uranium mining and reactor catastrophe as the worst of feasible nuclear accidents the author proceeds to discuss the risks from radioactivity. The fact that contact with sources of radioactivity has become an everyday problem has led to a general awareness of the health consequences and presence of radioactivity as a decisive cofactor. The report challenges the trust-worthiness of experts and discusses the possibilities for citizens to offer resistance. Radiation-related diseases cannot be cured without taking political action and here the focus of attention must be shifted from individual cases and the limited availability of medical treatment to long-term preventive measures to be taken on a population-wide basis. This appears indispensable in view of the risks posed by radioactivity. (BBR)

  3. Natural radioactivity

    International Nuclear Information System (INIS)

    This chapter performs an overview on natural sources, approaching cosmic and terrestrial radiations, resume of the world media of exposure to the natural radiation, and areas of high natural radioactivity

  4. Data on the radioactive contamination of some Hungarian foodstuffs and menus

    International Nuclear Information System (INIS)

    The radioactive contamination of different foods and menus has been investigated and the results have proved the activity from artificial contamination to be generally one, in special cases two orders of magnitude lower than that of natural potassium. The average activity of artificial radioactive substances incorporated in a human organism per day amounts to about 100 pCi. (K.A.)

  5. Radioactive pollution

    International Nuclear Information System (INIS)

    The basic data available to-day on radioactive pollution levels of various origins are compared to those of natural origin. In the year 2000, radioactive pollution from nuclear electricity will represent only one additional day of, natural irradiation per year. Human data now available on action of chronic irradiation are given, together with the results of very many experiments on animals. Finally, the risk evaluation which can be derived are analyzed, as well as the safety limits they imply

  6. Determination of the fission barrier height in fission of heavy radioactive beams induced by the (d,p)-transfer

    CERN Multimedia

    A theoretical framework is described, allowing to determine the fission barrier height using the observed cross sections of fission induced by the (d,p)-transfer with accuracy, which is not achievable in another type of low-energy fission of neutron-deficient nuclei, the $\\beta$-delayed fission. The proposed experiment [1] at the HIE-ISOLDE, using the ACTAR TPC, will thus provide the experimental information, which is not available at the moment and which is highly interesting for nuclear theory.

  7. On accumulation of radionuclides and on radiation induced in wood distortions in poplar from radioactively contaminated territories

    International Nuclear Information System (INIS)

    The results of measurements of accumulation of a alpha-particles and radiation induced distortions in wood samples of poplar taken from the districts of East Kazakhstan region, having an influence of Semipalatinsk and Lobnor nuclear test sites are presented. Noticeable correlation between annual rings width and accumulation of radionuclides or structure distortions in them was not revealed. Most probably the width of poplar rings to the largest degree depends on climate conditions, but not on their structural distortions. At the same time during the nuclear tests at Semipalatinsk Nuclear test site the rings in tree sawcuts were somewhat wider than in previous years

  8. Radioactivity Monitoring of the Irish Environment 2009

    International Nuclear Information System (INIS)

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland (RPII) during 2009. The RPII has routinely monitored levels of radioactivity in the environment since 1982 and this is the latest in the RPII's series of environmental monitoring reports. The RPII reviews and updates its environmental programme annually so as to ensure it remains relevant and continues to focus on the most important sources of radioactivity in the environment. The principal aims of the RPII's monitoring programme are; to assess the level of radioactivity to which the Irish population is exposed as a result of radioactivity in the environment; to study trends and establish the geographical distribution of contaminating radionuclides so as to better understand the long term behaviour of artificial radioactivity in the food chain and the environment; to ensure that any increase in radiation levels resulting from an accidental release of radioactivity to the environment is detected and assessed rapidly. During 2009 radioactivity was measured in a wide range of foods and environmental materials including: air, water, milk, seafood, foodstuffs and complete meals. The most significant source of artificial radioactivity in the Irish marine environment is the discharge of low level liquid radioactive waste from the Sellafield Nuclear Fuel Reprocessing Plant on the north east coast of England. In order to assess the exposure arising from the source extensive sampling of fish and shellfish landed at ports along the north east coast of Ireland is undertaken. The most exposed group of individuals to discharges from Sellafield have been identified as commercial oyster and mussel farmers working along the north east coastline and their families. Manmade radioactivity is also present in the terrestrial environment due primarily to residual global fallout arising primarily from atmospheric testing of nuclear weapons in the 1950s and 1960s and releases from past nuclear accidents such as Chernobyl. Milk, because it is an important foodstuff for infants and children and is known to concentrate long lived radionuclides such as caesium-137 and strontium-90, is an important indicator of levels of artificial radioactivity in the terrestrial food chain. The estimated dose due to strontium-90 activity in milk was estimated to be 0.97 ?Sv for 2009. This was for the most exposed group, assessed to be infants, children under the age of one year. It is very small compared to the background radiation. Radioactivity measurements on other foodstuffs confirm the levels of artificial radioactivity in the Irish food-chain remain very low and that Irish foodstuffs are free from harmful levels of radioactivity. The RPII monitors radioactivity in drinking water supplies in rotation so that major supplies from each county are sampled at least once every four years. During 2009 supplies from Galway, Kerry, Kildare, Kilkenny, Leitrim, Longford, Limerick and Laois were tested. Drinking water samples are assessed for compliance with the radioactivity standards set out in the Drinking Water Directive. All drinking water samples tested during 2009 were found to be in compliance with the radioactivity standards set out in the Drinking Water Directive. The RPII programme also monitors airborne radioactivity through its network of on- and off-line samplers. External gamma dose rates are also monitored. No exceptional activity was detected in outdoor air during 2009. The levels were consistent with those recorded in previous years. For 2009 the average annual dose from inhalation of caesium-137 was estimated at 9.0 x 10?? ?Sv. The data presented in this report confirm that while the levels of artificial radioactivity in the Irish environment are detectable they are low and are continuing to decrease. They do not pose a significant risk to the human health of the Irish population. Activity concentrations of radionuclides in airborne particulates were low and consistent with measurements made in recent y

  9. The radioactivity of the sea

    International Nuclear Information System (INIS)

    The radioactivity in the world's surface sea water averages 13.6 Bq/kg of water. Over 88% of this activity arises from a single natural radionuclide, 40K, and 7% of the remainder results from nuclear weapon test fallout. Variations in the radioactivity occur due to changes in salinity, weapon test fallout and discharges of artificial radionuclides, and are examined here on the basis of published measurements. The most radioactive sea identified by these measurements is the Dead Sea, which averages 178 Bq/kg due to its high salinity. Other enclosed, highly saline waters can be expected to have similar levels. The radioactivity in open seas varies within a much narrower range, generally within 20% of the world average. The highest averages are found in the Persian Gulf (22 Bq/kg), the Red Sea (15 Bq/kg) and the Eastern Mediterranean (14.6 Bq/kg). The Irish Sea averaged 13.7 Bq/kg in 1987, with the effect of the Sellafield discharges being partly offset by lower than average salinity. Although higher levels occurred in the Irish Sea during the 1970s when the Sellafield discharges were higher, the average level has always been much less than that in the Dead Sea, so that the Irish Sea has never been the most radioactive sea in the world. Exceptionally low levels of radioactivity (4 Bq/kg) occur in the Baltic Sea due to dilution by fresh water. (author)

  10. Processing method for radioactive wastes

    International Nuclear Information System (INIS)

    Upon processing radioactive wastes, especially, medium level wastes, a hollow underground structure is constructed in a base lock, and a partition is disposed therein. A vessel for radioactive wastes is hung down into each of the partitioned spaces, then the partition is pulled up, and the upper portion of the partition is dismantled and removed as much as the pulled up amount. Fillers are packed around the hung down vessels, and the hung down steps and the packing steps are repeated to stack the vessels to a predetermined height. With such a constitution, the partition acts as a vibration-proof guide or positioning means upon settling the vessels of radioactive wastes. Then, space for artificial barriers can be kept around the vessels, in addition, the processing cost can be reduced. (T.M.)

  11. Total Artificial Heart

    Science.gov (United States)

    ... the NHLBI on Twitter. What Is a Total Artificial Heart? A total artificial heart (TAH) is a ... outside power source. Normal Heart and CardioWest Total Artificial Heart Figure A shows the normal structure and ...

  12. Artificial Sweeteners and Cancer

    Science.gov (United States)

    Artificial Sweeteners and Cancer On This Page What are artificial sweeteners and how are they regulated in the United States? Is there an association between artificial sweeteners and cancer? What have studies shown about ...

  13. Artificial rheotaxis

    Science.gov (United States)

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

    2015-01-01

    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.

  14. Novel approaches to the analysis of nuclear and other radioactive materials - Improving detection capability through alpha-gamma coincidence, alpha-induced optical fluorescence and advanced spectrum analysis

    OpenAIRE

    Ihantola, Sakari

    2013-01-01

    Nuclear and other radioactive materials pose a special concern in the proliferation of nuclear weapons, reactor accidents or through criminal acts. To prevent the adverse effects of the use of these materials, novel approaches for their detection and analysis are required. The objective of the research in this thesis was to improve the detection and characterisation of nuclear and other radioactive materials with radiometric methods. Radioactive sources can be detected and identified base...

  15. Study of the behaviour of artificial radioactive aerosols. Applications to some problems of atmospheric circulation (1963); Etude du comportement dcs aerosols radioactifs artificiels. Applications a quelques problemes de circulation atmospherique (1963)

    Energy Technology Data Exchange (ETDEWEB)

    Lambert, G. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1963-11-15

    The aim of this work, consists in the examination of the behaviour of radioactive aerosols produced in the atmosphere by nuclear explosions, in order to deduce the most general laws governing atmospheric circulation and diffusion. After having given a general table of the radioactive aerosols present the authors consider the validity and the precision of the measurement methods and the concentration of the aerosols at ground level and in the upper atmosphere, as well as their deposition on the ground. The existence is thus demonstrated of a tropospheric equatorial barrier and of discontinuous and seasonal aspects of stratosphere-troposphere transfers. The role is shown of precipitations and dry auto-filtration in the lower atmosphere cleaning processes. This work makes it possible to describe the general behaviour of dust from the stratosphere, and to improve the total radioactive contamination of the globe. (author) [French] L'objectif de ce travail consiste a examiner le comportement des aerosols radioactifs introduits dans l'atmosphere par les explosions nucleaires, pour en deduire les lois les plus generals de la circulation et diffusion atmospheriques. Apres avoir dresse un tableau d'ensemble des aerosols radioactifs presents, on examine la validite et la precision des methodes de mesure de leur concentration, au niveau du sol et en haute atmosphere, ainsi que de leur depot a la surface du sol. On met ainsi en evidence l'existence d'une barriere equatoriale tropospherique; l'aspect discontinu et saisonnier des transferts stratosphere-troposphere; le role des precipitations et de l'auto-filtration seche, dans les processus de nettoyage de la basse atmosphere. Ces etudes permettent de decrire le comportement general des poussieres d'origine stratospherique et d'ameliorer le bilan de la contamination radioactive du globe. (auteur)

  16. The puzzle of nuclear wastes. Radioactive threat to your health..

    International Nuclear Information System (INIS)

    This document, published by the French association 'Sortir du nucleaire' (Get out of nuclear), gives some information on what is radioactivity, the radioactive materials as a risk for living organisms, nuclear wastes all over France (list and map of the storage sites, power plants and fuel cycle centers), nuclear wastes at every step of the nuclear connection, the insolvable problem of high activity wastes, burying nuclear wastes in order to better forget them, radioactivity as a time bomb for our health, radioactive effluents as an under-estimated risk, artificial radioactivity already responsible for the death of 61 million people in the world, and so on

  17. Única ou dupla inseminação artificial em tempo fixo em porcas com ovulações induzidas pelo Hormônio Luteinizante / Single or double artificial insemination in fixed time in sows with ovulation induced by Luteinizing Hormon

    Scientific Electronic Library Online (English)

    Paulo Henrique, Candini; Aníbal de Sant' Anna, Moretti; Eraldo Luis, Zanella; Paulo Roberto Souza da, Silveira; Carlos Henrique Cabral, Viana; Isabel, Santos.

    2004-04-01

    Full Text Available Duzentas e cinqüenta e quatro matrizes Camborough 22 (PIC®), foram divididas em 3 tratamentos: T 1 (n=60) - 600 UI de eCG após desmama e 5 mg de LH, 72 h após eCG , com única inseminação artificial (IA) (24 h após LH); T 2 (n=95) - mesmo tratamento hormonal do T1, com 2 IA (24 e 32 h após LH); T 3 ( [...] n=99) - grupo controle sem tratamento hormonal, com 3 IA. As médias de intervalo desmame-estro (IDE) em T1, T2 e T3 foram de 87,4 ± 3,0 (87 a 111), 87 ± 0 (87) e 99,9 ± 13,6 (63 a 135) horas, respectivamente, sendo reduzidas (P horas, respectivamente para T1, T2 e T3, sendo menor (P Abstract in english Two hundred fifty four sows Camborough 22 (PIC®), were divided in 3 treatments: T 1 (n=60) - 600 UI of eCG after weaning and 5 mg of LH, after 72 h, with single artificial insemination (AI) (24 h after LH); T 2 (n=95) - same hormonal treatment of T1, with 2 AI (24 and 32 h after LH); T 3 (n=99) - co [...] ntrol group, with 3 AI. The averages of weaning-to-estrus interval (WEI) in T1, T2 and T3 were of 87,4 ± 3,0 (87 - 111), 87 ± 0 (87) and 99,9 ± 13,6 (63 - 135) h, respectively, been reduced (P

  18. Environmental radioactivity surveillance programme 1990 - 1993

    International Nuclear Information System (INIS)

    During the period 1990-1993, the Radiological Protection Institute of Ireland continued its programme of measuring radioactivity levels in airborne dust, rainwater, total fallout, drinking water supplies and milk. The levels of artificially produced radionuclides continue to be insignificant from a radiological safety point of view

  19. Cluster Radioactivity

    Science.gov (United States)

    Gupta, Raj K.; Greiner, Walter

    This review summarizes both the experimental and theoretical status of cluster radioactivity. The contents are: a brief introduction, the experimental methods used and the results obtained, the theories of cluster radioactivity, cluster-decay as (cold) super-asymmetric spontaneous fission, and its fine structure. The theories studied are the unified fission models (UFM), the preformed cluster models (PCM), and the comparison between empirical and theoretical preformation probabilities. A brief discussion of other theories, not studied so much in detail, is also given. An overview of this research is added at the end, pointing out, in particular, its relation to other phenomena.

  20. Teaching concepts in the field of radioactivity and nuclear energy

    International Nuclear Information System (INIS)

    This issue of 'Naturwissenschaften im Unterricht', dealing with the subjects of physics and chemistry, gives an account of the fundamentals of radioactivity, nuclear fission, controlled nuclear fission, nuclear power plants, dosimetry, safety engineering, shielding measures to prevent the release of radioactive substances, pressure engineering, emergency core cooling systems, waste disposal and natural and artificial environmental radioactivity. Teachers will find helpful hints as to the method of instruction and the explanation of problems. (DG)

  1. Metrology of radioactive aerosols with automatic self-checking monitors

    International Nuclear Information System (INIS)

    The paper gives a technical description of an aerosol monitor for determining low concentrations of artificial radioactive aerosols in the atmosphere. The principle of measurement consists of determining the natural beta aerosol radioactivity concentration and subtracting it from the gross beta radioactivity concentration, based on a simultaneous alpha and beta measurement. The performance of the monitor is demonstrated with laboratory experiments and experiences related to the Chernobyl accident. The paper also describes further developments in the field using modern nuclear detectors

  2. Artificial Economy

    Directory of Open Access Journals (Sweden)

    Alexandru JIVAN

    2011-08-01

    Full Text Available This paper proposes to eliminate, a routine in the economic thinking, claimed to be responsible for the negative essence of economic developments, from the point of view, of the ecological implications (employment in the planetary ecosystem. The methodological foundations start from the natural origins of the functionality of the human economic society according to the originary physiocrat liberalism, and from specific natural characteristics of the humankind. This paper begins with a comment-analysis of the difference between natural and artificial within the economy, and then explains some of the most serious diversions from the natural essence of economic liberalism. It shall be explained the original (heterodox interpretation of the Classical political economy (economics, by making calls to the Romanian economic thinking from aggravating past century. Highlighting the destructive impact of the economy - which, under the invoked doctrines, we call unnatural - allows an intuitive presentation of a logical extension of Marshall's market price, based on previous research. Besides the doctrinal arguments presented, the economic realities inventoried along the way (major deficiencies and effects, determined demonstrate the validity of the hypothesis of the unnatural character and therefore necessarily to be corrected, of the concept and of the mechanisms of the current economy.The results of this paper consist of original heterodox methodspresented, intuitive or developed that can be found conclusively within the key proposals for education and regulation.

  3. Radioactivity Monitoring of the Irish Environment 2006

    International Nuclear Information System (INIS)

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland (RPII) in 2006. This programme aims to assess the exposure of the Irish population to artificial radioactivity in the environment, to review the temporal and geographical distribution of contaminating radionuclides and to maintain systems and procedures which would allow a rapid assessment of environmental contamination to be made in the event of a radiological emergency. Radioactivity is present in the environment due to natural processes, the testing of nuclear weapons in the atmosphere, past nuclear accidents such as that at Chernobyl in Ukraine and the routine discharge of radionuclides from nuclear installations. Liquid discharges from the British Nuclear Group reprocessing plant at Sellafield in Cumbria in the north-west of England, which are licensed by the UK Environment Agency, continue to be the dominant source of artificial radioactivity in the Irish marine environment. The key elements of the monitoring programme implemented by the RPII in 2006 included; assessment of ambient radioactivity based on measurements of radioactivity in air and of external gamma dose rate at permanent monitoring stations located throughout the country; assessment of levels of radioactivity in drinking water; assessment of levels of radioactivity in foodstuffs based on measurements of total diet, milk and various ingredients; assessment of levels of radioactivity in the Irish marine environment based on sampling and measurement of seawater, sediment, seaweed, fish and shellfish. The RPII monitored airborne radioactivity at ten stations located throughout the country. One of these stations is equipped with a high volume sampler, which allows concentrations of caesium-137 to be measured; another is equipped to detect the presence of the gas krypton-85. This gas is released into the environment primarily as a result of the reprocessing of nuclear fuel. During 2006, levels of radionuclides in airborne radioactivity were low and consistent with measurements in previous years. External gamma dose rates were monitored continuously at fifteen stations. No abnormal levels were observed. In accordance with the RPII's drinking water monitoring protocol, a number of water supplies from Cork, Dublin, Galway and Limerick were tested and found to be within the requirements for radioactivity set out in the relevant national standards. The RPII sampled and measured levels of radioactivity in mixed diet, milk and various other foodstuffs including milk products, baby foods, beef, lamb, poultry and vegetables. These measurements show that levels of artificial radioactivity in the Irish diet continue to be low. In the region of 170 samples of fish, shellfish, seaweed, seawater and sediment were analysed for a range of radionuclides. Along the Irish coastline the highest radioactivity concentrations observed were in the north-east. The main pathway contributing to the exposure of the Irish public to artificial radioactivity from the marine environment is the consumption of seafood. Caesium-137 continues to be the dominant radionuclide, accounting for approximately 70% of the total dose. The dose to the Irish population due to caesium-137 has declined significantly over the last two decades corresponding to the reduction in discharges of this radionuclide from Sellafield. The annual doses incurred by the Irish public as a result of artificial radioactivity in the environment do not constitute a significant health risk and are small compared with the dose received as a result of natural radiation

  4. Radioactivity and foods

    International Nuclear Information System (INIS)

    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 undesirable 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 Chernobyl. 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. 14 refs, 4 tabs

  5. Radioactivity of some dried fruits

    International Nuclear Information System (INIS)

    Full text: Radioactivity radiation from natural and artificial sources often acts at the same time in complicated combinations and without exception on all inhabitants of our planet. Natural and artificial radioactive isotopes pass into living organism by biological chain: soil-water-air-plants-foodstuffs-person and can be sources of inside irradiation. Accumulation of radionuclides in living organism in large quantities limit permissible concentration (LPC) can lead to pathological changes in organism. With above mentioned at the radioecological investigations, researches and control of changes of radionuclides concentration in environmental objects have important interests. Investigations of determination of radioactivity of environmental objects, which began in 1960 by professor Muso Muminov are continued in the department of nuclear physics of Samarkand State University. We work out semiconducting gamma-spectrometric method of determination of radionuclides concentration in weak -active environmental samples. We investigated radioactivity of different samples of natural environment and generalized results. In this work the results of investigation of radioactivity of same dried fruits are presented. The spectra of ?-radiation of following dried fruits as grapes, apricot, apple and peach was investigated. In measured gamma-radiation spectra of these samples gamma-transitions of 226Ra, 232Th, 40K natural radionuclides and product of 137Cs division. The specific gamma-activities these radionuclides were determined. The 40K have most specific activity and 137Cs - least. The calculated quantities of specific gamma-activity of radionuclides in gamma-spectra of investigated samples can replace to following row: 40K > 232Th > 226Ra > 137Cs

  6. Alternatives of applications in the information taking with artificial radioactive tools in the mature fields of the South region; Alternativas de aplicaciones en la toma de informacion con herramientas radiactivas artificiales en los campos maduros de la region Sur

    Energy Technology Data Exchange (ETDEWEB)

    Fuentes, J.L

    2005-07-01

    In this work it is widely described the application of the saturation control tool (RST) used in the campo Rodador (Mexico), and shortly the registration tools of location monitoring (RMT) and the Monitor tool of the location operation (RPM) used for the evaluation in site of the mature wells, had being at the present time these three tools with nuclear reaction mechanisms to obtain the water saturation and of hydrocarbon by means of the Neutron capture (PNC) and Inelastic scattering (IS). Both tools have been designed to help to the evaluation of the mature wells in the locations. Starting from measurements made through the lining pipe applying nuclear techniques used by these tools of registrations to derive the water saturation and of hydrocarbon. In this work the basic principles of radioactivity and their application in the radioactive tools are described as well as the operative aspects of the tools before mentioned, some practical applications of the saturation control tool are presented and a technical study of cost-benefit and it is shown as the technology advances have allowed to carry out considerable progresses in the taking of information of the mature wells helping by this way, to build better geological models in the locations that help to increase the hydrocarbon production in wells that have many years of exploitation. (Author)

  7. Chemical and isotopic characterization of water-rock interactions in shales induced by the intrusion of a basaltic dike: A natural analogue for radioactive waste disposal

    International Nuclear Information System (INIS)

    Disposal of nuclear waste in deep geological formations is expected to induce thermal fluxes for hundreds of years with maximum temperature reaching about 100-150 deg. C in the nearfield argillaceous environment. The long-term behavior of clays subjected to such thermal gradients needs to be perfectly understood in safety assessment considerations. In this respect, a Toarcian argillaceous unit thermally disturbed by the intrusion of a 1.1-m wide basaltic dike at the Perthus pass (Herault, France), was studied in detail as a natural analogue. The thermal imprint induced by the dike was evaluated by a mineralogical, chemical and K-Ar study of the <2 ?m clay fraction of shale samples collected at increasing distance from the basalt. The data suggest that the mineral composition of the shales was not significantly disturbed when the temperature was below 100-150 deg. C. Closer to the dike at 150-300 deg. C, changes such as progressive dissolution of chlorite and kaolinite, increased content of the mixed layers illite-smectite with more illite layers, complete decalcification and subsequent increased content of quartz, were found. At the eastern contact with the dike, the mineral and chemical compositions of both the shales and the basalt suggest water-rock interactions subsequent to the intrusion with precipitation of palagonite and renewed but discrete deposition of carbonate. A pencil cleavage developed in the shales during the dike emplacement probably favored water circulation along the contact. Strontium isotopic data suggest that the fluids of probable meteoric origin, reacted with Bathonian and Bajocian limestones before entering the underlying Toarcian shales. By analogy with deep geological radioactive waste repositories, the results report discrete mineralogical variations of the clays when subjected to temperatures of 100-150 deg. C that are expected in deep storage conditions. Beyond 150 deg. C, significant mineralogical changes may alter the physical and chemical properties of the shales, especially of the clay fraction. Also, the development of structural discontinuities in the so-called thermally disturbed zone might be of importance as these discontinuities might become zones for preferential fluid circulation. Finally, the study emphasizes the use of Rb-Sr and K-Ar isotopic systems as tracers of local circulating fluids related to low-grade thermal imprints

  8. Radioactivity Monitoring of the Irish Environment 2007

    International Nuclear Information System (INIS)

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland (RPII) in 2007. This programme aims to assess the exposure of the Irish population to artificial radioactivity in the envorinment, to review the temporal and geographical distribution of contaminating radionuclides and to maintain systems and procedures which would allow a rapid assessment of environmental contamination to be made in the event of a radiological emergency. In additiopn, some natural radioactivity exposure pathways are included in the programme including radioactivity in surface and ground drinking water. Radioactivity is present in the environment due to natural oprocesses, the testing of nuclear weapons in the atmosphere, past nuclear accidents such as that at Chernobyl in the Ukraine and the routine discharge of radionuclides from nuclear installations. Liquid discharges from the British Nuclear Group reprocessing plant at Sellafield in Cumbria in the north-west of England continue to be the dominant source of artificial radioactivity in the Irish marine environment. The key elements of the monitoring programme implemented by the RPII in 2007 included; assessment of ambient radioactivity based on measurements of radioactivity in air and of external gamma dose rate at permanent monitoring stations located throughout the country; assessment of levels of radioactivity in drinking water; assessment of levels of radioactivity in foodstuffs based on measurements of total diet, milk and various ingredients; assessment of levels of radioactivity in the Irish marine environment based on sampling and measurement of seawater, sediment, seaweed, fish and shellfish. The RPII monitored airborne radioactivity at twelve stations located throughout the country. One of these stations is equipped with a high volume sampler, which allows background concentrations of caesium-137 to be measured; another is equipped to detect the presence of the gas krypton-85. This gas is released into the environment primarity as a result of the reprocessing of nuclear fuel. During 2007, levels of radionuclides in airborne radioactivity were low and consistent with measurements in previous years. External gamma dose rates were monitored continuously at fifteen stations. No abnormal levels were observed. A major upgrade of the aerosol sampling equipment began in 2007 when three on-line low volume systems and seven upgraded off-line low volume systems were installed and commissioned. Two additional on-line sites will be added in 2008. In accordance with the RPII's drinking water monitoring protocol, a number of major water supplies from Cork, Dublin, Galway and Limerick were tested and found to be within the requirements for radioactivity set out in the relevant national standards. In addition, groundwater supplies were tested in nine countries as a pilot for a national survey of ground water scheduled for 2008 to 2010. The RPII sampled and measured levels of radioactivity in mixed diet, milk and various other foodstuffs including milk products, baby foods, beef, lamb and poultry. These measurements show that the levels of artificual radioactivity in the Irish diet continue to be low. One hundred and ninety samples of fish, shellfish, seaweed, seawater and sediment were analysed for a range of radionuclides. Along the Irish coastline the highest activity concentrations observed were in the north-east. The main pathway contributing to the exposure of the Irish public to artificial radioactivity from the marine environment is the consumption of seafood. Caesium-137 continues to be the dominant radionuclide, accounting for approximately 84% of the total dose. The dose to the Irish population from consumption of seafood landed at north-east ports has declined significantly over the last two decades corresponding to the reduction in discharges from Sellafield. The annual doses incurred by the Irish public as a result of artificial radioactivity in the environment do not constitute a significant he

  9. Gas and water flow in an excavation-induced fracture network around an underground drift: A case study for a radioactive waste repository in clay rock

    Science.gov (United States)

    de La Vaissière, Rémi; Armand, Gilles; Talandier, Jean

    2015-02-01

    The Excavation Damaged Zone (EDZ) surrounding a drift, and in particular its evolution, is being studied for the performance assessment of a radioactive waste underground repository. A specific experiment (called CDZ) was designed and implemented in the Meuse/Haute-Marne Underground Research Laboratory (URL) in France to investigate the EDZ. This experiment is dedicated to study the evolution of the EDZ hydrogeological properties (conductivity and specific storage) of the Callovo-Oxfordian claystone under mechanical compression and artificial hydration. Firstly, a loading cycle applied on a drift wall was performed to simulate the compression effect from bentonite swelling in a repository drift (bentonite is a clay material to be used to seal drifts and shafts for repository closure purpose). Gas tests (permeability tests with nitrogen and tracer tests with helium) were conducted during the first phase of the experiment. The results showed that the fracture network within the EDZ was initially interconnected and opened for gas flow (particularly along the drift) and then progressively closed with the increasing mechanical stress applied on the drift wall. Moreover, the evolution of the EDZ after unloading indicated a self-sealing process. Secondly, the remaining fracture network was resaturated to demonstrate the ability to self-seal of the COx claystone without mechanical loading by conducting from 11 to 15 repetitive hydraulic tests with monitoring of the hydraulic parameters. During this hydration process, the EDZ effective transmissivity dropped due to the swelling of the clay materials near the fracture network. The hydraulic conductivity evolution was relatively fast during the first few days. Low conductivities ranging at 10-10 m/s were observed after four months. Conversely, the specific storage showed an erratic evolution during the first phase of hydration (up to 60 days). Some uncertainty remains on this parameter due to volumetric strain during the sealing of the fractures. The hydration was stopped after one year and cross-hole hydraulic tests were performed to determine more accurately the specific storage as well as the hydraulic conductivity at a meter-scale. All hydraulic conductivity values measured at the injection interval and at the observation intervals were all below 10-10 m/s. Moreover, the preferential inter-connectivity along the drift disappeared. Specific storage values at the observation and injection intervals were similar. Furthermore they were in agreement with the value obtained at the injection interval within the second hydration phase (60 days after starting hydration). The graphical abstract synthesizes the evolution of the hydraulic/gas conductivity for 8 intervals since the beginning of the CDZ experiment. The conductivity limit of 10-10 m/s corresponds to the lower bound hydraulic definition of the EDZ and it is demonstrated that EDZ can be sealed. This is a significant result in the demonstration of the long-term safety of a repository.

  10. Radioactivity monitor

    International Nuclear Information System (INIS)

    Purpose: To measure low-level radioactivity in an exhaust gas discharged from a nuclear power station. Constitution: Two valves are provided at two points of a pipe through which the exhaust gas is passed. The gas between two valves can be separated from gas in the other parts of the pipe. A bypass pipe is provided at the outer parts of the aforementioned two valves. The pipe at one side can be maintained in live state. In order to use the part isolated by the two valves as an ionization chamber, high insulators such as teflon and the like are provided at the inner sides of two valves. By applying a voltage of from 5 -- 600 to 5 -- 6000 volts to the isolated part thereby to collect ions inside the part, and the radioactivity is measured by the detection of beta-ray. Since the beta-ray is utilized, radioactive rays having short range can be measured with good efficiency. (Ikeda, J.)

  11. The natural radioactivity of the biosphere

    International Nuclear Information System (INIS)

    Of the approximately 1200 isotopes presently known more than 900 are radioactive. The nuclei of these isotopes are unstable and decay spontaneously emitting ionizing gamma-, alpha- or beta-radiation. The overwhelming majority of known radioactive isotopes have been obtained artificially; only a few are natural. Numerous investigations have shown that many of the natural radioactive isotopes can be grouped into three radioactive families. Each such family is characterized by the existence of one long-lived isotope - the family parent, one gaseous isotope of radon, intermediate radioactive decay products and final stable isotopes of atomic weights 206, 207 and 208. No such generic relationship has been established among the remaining natural radioactive isotopes. The purpose of the book, in contrast to some recent review works, is to present, in addition to a summary of reference data characterizing the radioactivity levels of various components of the biosphere, a description of those phenomena and regularities which will apparently make it possible to understand more completely the basic dynamics of the natural radioactivity of the biosphere and, consequently, contribute to a more correct interpretation of radiation-hygiene in each specific case

  12. HUMAN EXPOSURE TO THE ARTIFICIAL RADIONUCLIDES IN ENVIRONMENT

    OpenAIRE

    Ivana Vukanac; Aleksandar Kandic; Mirjana Duraševic; Bojan Seslak

    2012-01-01

    Artificial radionuclides are product of different human activities and their presence in the environment is negative side effect of civilization progress. They have been spread in the environment by events such as nuclear weapon tests, nuclear accidents and by deliberate and negligent discharge of radioactive waste from nuclear and other installation. Once released in to the nature, the artificial radionuclides start to circle in the same manner as naturally occurring ones, and finally they f...

  13. Artificial Radiotracer Applications in Aquatic Environments

    International Nuclear Information System (INIS)

    The use of artificial radiotracers in the environment is analogous to their use in the human body. In both domains they provide data on flow rates and pathways, on exchange with materials and on their final discharge from the studied system. Artificially injected radiotracers have been used to investigate flow in natural waters since the 1950's. Identification of flow paths, diagnosis of blockages or leakage, measurement of flow rates, dispersion and exchange processes, such as biological uptake or sorption, are all aspects to which a wide range of artificial radioactive tracers have been applied. Increasingly radiotracers are used in combination with numerical modelling to improve confidence in the predictive capacity of models used in the management of our water resources and to extend their spatial applicability. In turn this allows us to use less and less tracer and demonstrate that the human and environmental impact of modern radiotracer studies is minimal. (author)

  14. Radioactivity and fusion energy

    International Nuclear Information System (INIS)

    Nuclear fusion is expected to give an ultimate solution to energy problems over the long term. From recent progress in developing technology for fusion reactors, we can anticipate a prototype fusion reactor by 2030. This review article describes the present status of nuclear fusion research, including muon catalyzed fusion (?CF) which attracts quite new physical interest. Tritium is an essential component of fusion reactors, because the first-stage fusion reactors will utilize a mixture of deuterium and tritium as their fuel. The knowledge about tritium as well as the fusion-neutron induced radioactivity is summarized in terms of nuclear fusion research. (orig.)

  15. Radioactivity telemetry

    International Nuclear Information System (INIS)

    The authors present an assembly which aims at radio-transmitting from mobile stations information on radioactivity. It comprises 20 mobile stations which can be located within the Cadarache Centre or outside of it within a 10 km radius, and a central station which centralises information. The report proposes a general presentation of these stations, their characteristics and principles of operation. It describes operation sequences, central station functions (call programmer, address and memory management, recording, peripherals) and its energy supply, and mobile station functions. The last part presents the installation, its start-up and exploitation, its threshold devices and its safety device

  16. Artificiality in Social Sciences

    OpenAIRE

    Rennard, Jean-Philippe

    2007-01-01

    This text provides with an introduction to the modern approach of artificiality and simulation in social sciences. It presents the relationship between complexity and artificiality, before introducing the field of artificial societies which greatly benefited from the computer power fast increase, gifting social sciences with formalization and experimentation tools previously owned by "hard" sciences alone. It shows that as "a new way of doing social sciences", artificial soc...

  17. Artificial Intelligence and Wittgenstein

    OpenAIRE

    Casey, Gerard

    1988-01-01

    The association of Wittgenstein’s name with the notion of artificial intelligence is bound to cause some surprise both to Wittgensteinians and to people interested in artificial intelligence. After all, Wittgenstein died in 1951 and the term artificial intelligence didn’t come into use until 1956 so that it seems unlikely that one could have anything to do with the other. However, establishing a connection between Wittgenstein and artificial intelligence is not as insuperable a...

  18. Radioactivity and Environment. Radioactividad y Medio Ambiente

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Leon, J.G. (Jefe de Seguridad Nuclear de la Fabrica de Juzbado. Empresa Nacional de Uranio. (Spain))

    1993-01-01

    Radioactivity is one of the most studied natural phenomena. Most of irradiation suffered by the human being is produced by natural sources. The second source in order of importance is nuclear medicine. The average level of radiation received by the man is 2.4 mSv/year and this value can be modified naturally in 20-30%. The author provides a review on radioactivity sources like natural (cosmic rays, extraterrestrial radiation, internal earth radiation, radon) and artificial (Nuclear explosions, professional exposure, nuclear medicine, nuclear power plants and accidents).

  19. Environmental radioactivity

    International Nuclear Information System (INIS)

    The evaluation of more than 50 official points of measurement for the control of environmental radioactivity in the German Federal Republic showed a marked decrease of activity concentration in the surveyed fields of precipitation, air, water, milk, and humans as compared to 1972. This decrease can be attributed to the stop of above-ground nuclear weapons tests effected in 1963. In 1973, a survey of the environment of nuclear power stations again did not show any significant difference between these regions and others. The mean genetic radiation exposure in the year 1973 is given in a chart. Selected data from different places of measurement give mean values and annual balances of the radionuclides 137Cs and 90Sr for men, women, and children, as well as for cistern water, milk, and hospital food. Finally, a balance of the import and export of radionuclides in 1973 is given. (ORU/AK)

  20. Radioactive colloids

    International Nuclear Information System (INIS)

    Different techniques for the characterization of radioactive colloids, used in nuclear medicine, have been evaluated and compared. Several radioactive colloids have been characterized in vitro and in vivo and tested experimentally. Colloid biokinetics following interstitial or intravenous injection were evaluated with a scintillation camera technique. Lymphoscintigraphy with a Tc-99-labelled antimony sulphur colloid was performed in 32 patients with malignant melanoma in order to evaluate the technique. Based on the biokinetic results, absorbed doses in tissues and organs were calculated. The function of the reticuloendothelial system has been evaluated in rats after inoculation with tumour cells. Microfiltration and photon correlation spectroscopy were found to be suitable in determining activity-size and particle size distributions, respectively. Maximal lymph node uptake following subcutaneous injection was found to correspond to a colloid particle size between 10 and 50 nm. Lymphoscintigraphy was found to be useful in the study of lymphatic drainage from the primary tumour site in patients with malignant melanoma on the trunk. Quantitative analysis of ilio-inguinal lymph node uptake in patients with malignant melanoma on the lower extremities was, however, found to be of no value for the detection of metastatic disease in lymph nodes. High absorbed doses may be received in lymph nodes (up to 1 mGy/MBq) and at the injection site (about 10 mGy/MBq). In an experimental study it was found that the relative colloid uptake in bone marrow and spleen depended on the total number of intravenously injected particles. This may considerably affect the absorbed dose in these organs. (author)

  1. Radioactivity values in the river Elbe

    International Nuclear Information System (INIS)

    The largest portion of artificially produced radionuclides that currently gets into the river Elbe still stems from the fallout of supra-terrestrial atom bomb tests carried through decades ago in part. On the basis of a longitudinal profile of the Elbe from Schnackenburg to the Elbe estuary, no measurable increases were ascertained in the course of the systematic investigations pointing to artificial radionuclides of regional origin. This is also true of the nuclear power plants situated on the river Elbe. The amounts of radioactive nuclides, accurately known from emission measurements, which are discharged with sewage water from the Stade and Brunsbuettel nuclear power plants and reach the Elbe are so slight that they result in no measurable increase in radioactive nuclide levels in the Elbe. This is confirmed by the theoretical calculation. (orig./PW)

  2. Radioactivity analyses of food and drinking water in China following the Fukushima nuclear accident

    International Nuclear Information System (INIS)

    Objective: To summarize the analytical results of radioactivity in the food and drinking water nationwide following the Fukushima nuclear accident, and to evaluate its possible contamination to the public health in China. Methods: According to the national standard methods and IAEA, FDA correlative references,the scheme was established on sampling and measurements in food and drinking water after the breakout of the accident. The quality control was requested on the sampling, analyses and data report. Results: Trace artificial radioactive isotope of 131I was measured in spinach samples on 2 April 2011 in Beijing. Subsequently 131I was found in 10 kinds of growing leaves vegetables (open field)nationwide. The maximum detectable activity of 131I in vegetables was about 3.1 Bq/kg. Since 3 May 2011, the concentration of 131I has been below the detection limits.No artificial radionuclide was detectable in all of milk, drinking water and marine products samples during March to December, 2011. Conclusions: The food and drinking water measurements in China following the Fukushima nuclear accident denoted that the minor amounts of 131I in vegetables might result in very low absorbed dose and induce no impact on human health. The maximum detectable activity of 131I in vegetables was close to that reported in European countries,and much less than that measured in China immediately after the Chernobyl accident in 1986. (authors)

  3. Rays. Dangers of radioactivity and chemistry

    International Nuclear Information System (INIS)

    The book comprises eight chapters, their headings reading as follows: Natural and artificial radioactivity - Energything lives in the nuclear energy cycle - Isotopes, invisible destroyers - Thermal pollution of the biosphere - Environmental chemicals, an additional burden - Medicine, risk and rescue - Genetics, science of decision - The false priests. Each chapter is preceded by a number of theses as an introduction into the problems discussed and tables, diagrams and 944 bibliographic references are included in order to explain the author's argumentation. (HP)

  4. Environmental radioactivity

    International Nuclear Information System (INIS)

    Outline summary of a report prepared under contract to the DOE: Research Priorities and UK Estuaries: An Overview identifying Research Requirements. Topics considered include the study of radionuclides released into the NE Irish Sea from BNFL, Sellafields, differences in the isotopic composition of stable lead in various sediments, the concentration and distribution of 'hot particles' derived from BNFL in the Irish Sea and adjacent areas, together with attempts to separate hot particles from sediments, and the composition and properties of marine surfaces in relation to uptake and loss of radionuclides, particularly in relation to the common mussel, Mytilus edulis. The problem of the presence of transuranic radionuclides in the bottom sediments of the NE Irish Sea is considered. Profiles of radioactivity are being developed at the shelf-break in order to determine the transfer of radionuclides from the sea surface to the deep sea and to coastal waters; organisms examined include phytoplankton, zooplankton and crustacea (shrimps). Organisms such as Acantharia have been examined to determine transfer of elements and radionuclides to skeletal structures eg Sr, Ba and Si. (U.K.)

  5. Radioactive decontamination

    International Nuclear Information System (INIS)

    It discusses radioactive decontamination from the practical point of view with aim of contributions to safety control of radioisotopes. As general knowledges, contamination forms are explained from physical states of solid materials' surfaces and classification of contaminative mechanism are conducted in each contamination form. Furthermore, the decontaminants selcted for each classified contaminative mechanism are indicated from pH-effect and concentration effect. Decontamination on laboratory, using wet method generally as a decontamination technic includes irrigation method by decontaminant solution and scrubbing method. Decontamination of machinery and tools includes scrubbing method and the methods using ultrasonic decontamination equipment and semiautomatic decontamination equipment of which flow-diagram is illustrated. The methods of decontamination of clothing include its disposal or the use of tightly-closed full automatic washing machine. The general irrigation method are indicated as decontamination of skin. Furthermore, neutral cleaning material method for elimination of short-term elapsed contamination and Titanium oxide paste method for elimination of long-term elapsed contamination are explained. (Kanao, N.)

  6. Radioactive Substances in Metallurgical Waste

    International Nuclear Information System (INIS)

    Modern steel making technology in electric arc furnaces today is inconceivable without the use of steel scrap. In addition to radioactive elements 137Cs and 60Co which have so far been found in steel scrap, polluting thus both steel and steel products, 226Ra, 192Ir, 241Am, 232Th, and 90Sr are most represented. During the technological process the named radionuclides are distributed across heat, slag and dust, depending on their chemical and physical properties. Radionuclides which end up in the heat, slag, or dust, act radio-actively for a long period of time, depending on the duration of semi-decomposition of each single isotope. Due to the potential presence of radioactive elements in metallurgical scrap (steel scrap, EAF (electric arc furnace) slag, EAF dust) and in other materials from the EAF process, the process of their identification has been initiated. Gamma-spectrometric analysis (Canberra spectrometric system with Ge-detector) was applied on samples from the steel mill at Sisak Steelworks and from the Felis Foundry in Sisak. The presence of natural isotopes 40K, 226Ra, 232Th and 238U as well as of the artificial isotope 137Cs was established.(author)

  7. Environmental radioactivity and radiation exposure

    International Nuclear Information System (INIS)

    The environmental radioactivity in the Federal Republic of Germany was almost as high in 1976 as in 1975. It only increased temporarily in autumn 1976 as a result of the above-ground nuclear weapons test of the People's Republic of China on September 29th 1976 and then returned to its previous level. The radioactivity in food had a slight decreasing trend in 1976, apart from a temporary increase in the radioactivity in milk also caused by the nuclear weapons test mentioned. The population exposure remains basically unchanged in 1976 compared with 1975. The artificial radiation exposure is about half as high as the natural radiation exposure to which man has always been exposed. The former is based to 83% on using X-rays in medicine, particularly for X-ray diagnostic purposes. The population exposure due to nuclear power plants and other nuclear plants is still well below 1% of the natural radiation exposure although in 1976 three new nuclear power plants were put into operation. This is also true for the average radiation exposure within an area of 3 km around the nuclear plant. (orig.)

  8. Gene Silencing Using 4'-thioDNA as an Artificial Template to Synthesize Short Hairpin RNA Without Inducing a Detectable Innate Immune Response.

    Science.gov (United States)

    Tarashima, Noriko; Ando, Hidenori; Kojima, Takamitsu; Kinjo, Nozomi; Hashimoto, Yosuke; Furukawa, Kazuhiro; Ishida, Tatsuhiro; Minakawa, Noriaki

    2016-01-01

    The development of a versatile technique to induce RNA interference (RNAi) without immune stimulation in vivo is of interest as existing approaches to trigger RNAi, such as small interfering RNA (siRNA) and plasmid DNA (pDNA) expressing short hairpin RNA (shRNA), present drawbacks arising from innate immune stimulation. To overcome them, an intelligent shRNA expression device (iRed) designed to induce RNAi was developed. The minimum sequence of iRed encodes only the U6 promoter and shRNA. A series of iRed comprises a polymerase chain reaction (PCR)-amplified 4'-thioDNA in which any one type of adenine (A), guanine (G), cytosine (C), or thymine (T) nucleotide unit was substituted by each cognate 4'-thio derivatives, i.e., dSA iRed, dSG iRed, dSC iRed, and ST iRed respectively. Each modified iRed acted as a template to transcribe shRNA with RNAi activity. The highest shRNA yield was generated using dSC iRed that exerted gene silencing activity in an orthotopic mouse model of mesothelioma. Reducing the minimal structure required to transcribe shRNA and the presence of the 4'-thiomodification synergistically function to abrogate innate immune response induced by dsDNA. The iRed will introduce a new approach to induce RNAi without inducing a detectable innate immune response. PMID:26730811

  9. HUMAN EXPOSURE TO THE ARTIFICIAL RADIONUCLIDES IN ENVIRONMENT

    Directory of Open Access Journals (Sweden)

    Ivana Vukanac

    2012-09-01

    Full Text Available Artificial radionuclides are product of different human activities and their presence in the environment is negative side effect of civilization progress. They have been spread in the environment by events such as nuclear weapon tests, nuclear accidents and by deliberate and negligent discharge of radioactive waste from nuclear and other installation. Once released in to the nature, the artificial radionuclides start to circle in the same manner as naturally occurring ones, and finally they fall out from air and water onto the ground and build into the foodstuff and drinking water resulting in radiation doses to human beings. The short overview of presence of artificial radioactivity in human environment and its impact on human life is presented in this paper.

  10. Artificial cognition architectures

    CERN Document Server

    Crowder, James A; Friess, Shelli A

    2013-01-01

    The goal of this book is to establish the foundation, principles, theory, and concepts that are the backbone of real, autonomous Artificial Intelligence. Presented here are some basic human intelligence concepts framed for Artificial Intelligence systems. These include concepts like Metacognition and Metamemory, along with architectural constructs for Artificial Intelligence versions of human brain functions like the prefrontal cortex. Also presented are possible hardware and software architectures that lend themselves to learning, reasoning, and self-evolution

  11. Anticipatory Artificial Autopoiesis

    OpenAIRE

    Dubois, Daniel; Holmberg, Stig C.

    2010-01-01

    In examining relationships between autopoiesis and anticipation in artificial life (Alife) systems it is demonstrated that anticipation may increase efficiency and viability in artificial autopoietic living systems. This paper, firstly, gives a review of the Varela et al [1974] automata algorithm of an autopoietic living cell. Some problems in this algorithm must be corrected. Secondly, a new and original anticipatory artificial autopoiesis algorithm for automata is presented. ...

  12. Disposal of radioactive wastes

    International Nuclear Information System (INIS)

    Radioactive waste management and disposal requirements options available are discussed. The possibility of beneficial utilization of radioactive wastes is covered. Methods of interim storage of transuranium wastes are listed. Methods of shipment of low-level and high-level radioactive wastes are presented. Various methods of radioactive waste disposal are discussed

  13. An artificial muscle computer

    Science.gov (United States)

    Marc O'Brien, Benjamin; Alexander Anderson, Iain

    2013-03-01

    We have built an artificial muscle computer based on Wolfram's "2, 3" Turing machine architecture, the simplest known universal Turing machine. Our computer uses artificial muscles for its instruction set, output buffers, and memory write and addressing mechanisms. The computer is very slow and large (0.15 Hz, ˜1 m3); however by using only 13 artificial muscle relays, it is capable of solving any computable problem given sufficient memory, time, and reliability. The development of this computer shows that artificial muscles can think—paving the way for soft robots with reflexes like those seen in nature.

  14. Artifacts and Artificial Science

    OpenAIRE

    Beckman, Svante; Nilsson, Göran B.; Dahlbom, Bo

    2002-01-01

    In the Spring of 1968, Herbert Simon gave a series of lectures at Massachusetts Institute of Technology, introducing his idea of a science of the artificial. “The world we live in today is much more a man-made, or artificial, world than it is a natural world,” he began to say, but modern science is a science of nature. “Natural science is knowledge about natural objects and phenomena. We ask whether there cannot also be “artificial” science–knowledge about artificial objects and phenomena.” H...

  15. Radioactive pollution

    International Nuclear Information System (INIS)

    The widely published claims that the public health effects resulting from routine emissions are between 0.01 and 0.1 serious health effects per gigawattyear, and hence are at least a thousand times smaller than those resulting from air pollution by the burning of coal, cannot be true, for two reasons. The authors of these claims have ignored at least two of the more important isotopes, radon-222 and carbon-14, which are presently released to the environment, and thus contribute greatly to the health impact of nuclear energy. The health effects calculated in the earlier work cover only those which occur during the year in which the energy is generated. This means, figuratively speaking, that the authors have confused an annual installment payment with the full cost. This is unacceptable. The contribution to the health impact of nuclear energy arising from the single isotopic species radon-222 emanating from the mill tailings is estimated to 400 lung cancer deaths/GW(e)y, larger even than the most pessimistic estimates of the health impact of energy from coal through atmospheric pollution. We have no assurance that other long-lived isotopes do not contribute comparable amounts to the health impact of nuclear energy. The discussion of the health impact of radon-222 raises the fundamental moral question--how far into the future our responsibility extends. If such a long-termresponsibility is rejected, then we must at least try to predict the environmental buildup of radioactive pollutants, in order to avoid unacceptable and irreversible levels of radiation dose rate. The potential health consequences from long-lived radioisotopes seem to have been largely ignored so far, and should be explored in detail

  16. Monitoring of radioactivity in the marine environment

    International Nuclear Information System (INIS)

    The necessity of radioactivity monitoring in the marine environment was imposed by the increasing development of nuclear power and its world-wide use in many different segments of economic and social life. Both natural and artificial radioactivity play an important role in marine ecology and human health. In this respect three major facts continue to prevail in Romania. The fallout, the presence of the Danube river and the expectations for future energy production. Spatial and temporal monitoring of marine radioactivity along the Romanian Black Sea shore has been systematically performed in the Romanian Marine Research Institute in close co-operation with the Institute of Meteorology and Hydrology since 1981. Marine emerged and submerged sediments, coastal and offshore sea water, macroalgae, in vertebrates and fish off the Danube mouths and/or along the coast are monitored for natural and artificial radioactivity by means of beta gross measurements and gamma spectrometry. Concentrations of radionuclides as K-40, Cs-134, Cs-137 in abiotic and biotic samples, environmental distributions coefficients and concentrations factors (CF), as well as experimentally-derived CFs in marine biota as radioecological bioindicators are assessed and stored for a national data base. (author) 3 tabs., 18 refs

  17. Radioactive monitoring of the marine environment

    International Nuclear Information System (INIS)

    Radioactivity monitoring of marine environment was required by the development of nuclear power and the worldwide use of ionizing radiations in many different activities. Both natural and artificial radioactivity play an important role in marine ecology and human health. In respect of this, three major facts prevail, namely: the fallout, the proximity of Danube River and the future nuclear power production. Spatial and temporal monitoring of marine radioactivity along the Romanian Black Sea shore has been systematically performed in Romanian Marine Research Institute in close cooperation with Institute of Meteorology and Hydrology since 1981. Marine emerged and submerged sediments, coastal and offshore sea water, macroalgae, invertebrates and fish of Danube mouths and/or along the coast are monitored for natural and artificial radioactivity by means of gross beta measurements and gamma spectrometry. Concentrations of radionuclides such as: K-40, Cs-134 and Cs-137 in abiotic and biotic samples, environmental distribution coefficients and concentration factors (CFs) as well as experimentally derived CFs in marine biota as radioecological bioindicators are assessed and stored in a national data base. (author)

  18. Distribution of radioactive constituents in river waters

    International Nuclear Information System (INIS)

    For a research project on the distribution and evaluation of natural and artificial radioactive constituents in ecological segments of Biscay (northeast spain), the amounts of nuclides present in the main river waters were measured. Radioactive procedures include i) total alpha and beta indexes with a gas flow detector, dry residues near to 2 and 10 mg/ cm sup 2, respectively and counting periods of 1000 mn, ii) gamma emitters with a low level gamma spectrometer (Ge-HP detector + 8000 channels analyser) using the dry residue from 8 litres and a counting period of 4 days and iii) statistical treatment of data at 95% confidence.In this paper, ten water samples from the nervion river basin are included. Physical and chemical parameters of samples were also determined by standard procedures, because there is a sharp change in the composition of this river in the first part of the course. Radioactive constituents were identified as follows: a sample has a detectable alpha index, all samples contains beta emitters with a high variability, natural nuclides from uranium and thorium families were detected in some cases. A parallel behaviour is found between samples where K-40 and Cs-137 were found. The paper tries at last to find relations among chemical and radioactive constituents by the application of multivariate statistical methods, specially for the case of Cs-137, the only artificial nuclide identified in this work. 1 tab., 2 figs., 5 refs. (author)

  19. Radioactivity and Nuclear Issues in Science Fiction

    International Nuclear Information System (INIS)

    In this work are presented and reviewed science fiction narratives, films and comics that exploit radioactivity and nuclear issues. These topics to some science fiction authors serve as metaphor of evil and holocaust as well as nice instrument for elaborating various manipulations and conspiracy theories. In that context are of special interest science fiction works depicting apocalyptic post-nuclear worlds and societies, such works being closely connected with cyberpunk genre. However, other more technologically optimistic authors nuclear energy and research regarding nuclear technology and radioactivity consider as eligible and inevitable solution for world peace and prosperity Nowadays, public interest and global fears are shifted from radioactivity and nuclear issues to other catastrophic scenarios threatening future of the mankind, these for example being climate changes and global warming, asteroid impact, collapse of information infrastructure, nanotechnology, robotics and artificial intelligence etc. Consequently, these issues are as well increasingly reflected in contemporary science fiction stories.(author)

  20. Radiation protection. Radioactivity and health. 3. ed.

    International Nuclear Information System (INIS)

    This booklet makes an attempt at elucidating the mutual influence of radioactivity and health in a way which is understandable to the non-expert. The basics of radioactivity are briefly explained by way of introduction, the next item to be described is exposure of man to natural and artificial radiation. Somatic and genetic effects of radiation on man are subsequently discussed. The whole area of radioecology - starting with radioactive discharge from nuclear plants and going on to the determination of man's exposure to radiation - is covered and supplemented by a description of the risks of radiation therapy. All this serves to describe the results of long-term research on questions of the radiobiological risks in an understandable way and provide useful information about this eminently important area. (orig.)

  1. Artificial life and life artificialization in Tron

    Directory of Open Access Journals (Sweden)

    Carolina Dantas Figueiredo

    2012-12-01

    Full Text Available Cinema constantly shows the struggle between the men and artificial intelligences. Fiction, and more specifically fiction films, lends itself to explore possibilities asking “what if?”. “What if”, in this case, is related to the eventual rebellion of artificial intelligences, theme explored in the movies Tron (1982 and Tron Legacy (2010 trat portray the conflict between programs and users. The present paper examines these films, observing particularly the possibility programs empowering. Finally, is briefly mentioned the concept of cyborg as a possibility of response to human concerns.

  2. Marcos da história da radioatividade e tendências atuais Landmarks in the history of radioactivity and current tendencies

    OpenAIRE

    Allan Moreira Xavier; André Gomes de Lima; Camila Rosa Moraes Vigna; Fabíola Manhas Verbi; Gisele Gonçalves Bortoleto; Karen Goraieb; Carol Hollingworth Collins; Maria Izabel Maretti Silveira Bueno

    2007-01-01

    The first days of radioactivity, the discoveries of X-rays, radioactivity, of alpha- and beta- particles and gamma- radiation, of new radioactive elements, of artificial radioactivity, the neutron and positron and nuclear fission are reviewed as well as several adverse historical marks, such as the Manhattan project and some nuclear and radiological accidents. Nuclear energy generation in Brazil and the world, as an alternative to minimize environmental problems, is discussed, as are the medi...

  3. Progress in artificial intelligence

    Energy Technology Data Exchange (ETDEWEB)

    Steels, L.; Campbell, A.

    1985-01-01

    This guide explores the most recent and significant achievements attained in the field of artificial intelligence through the fifth generation computing plan. Discussions center around problem-solving and learing, knowledge-representation, reasoning and control, artificial intelligence and external relations, and applications.

  4. Processing semblances induced through inter-postsynaptic functional LINKs, presumed biological parallels of K-lines proposed for building artificial intelligence

    OpenAIRE

    KunjumonIVadakkan

    2011-01-01

    The internal sensation of memory, which is available only to the owner of an individual nervous system, is difficult to analyze for its basic elements of operation. We hypothesize that associative learning induces the formation of functional LINK between the postsynapses. During memory retrieval, the activation of either postsynapse re-activates the functional LINK evoking a semblance of sensory activity arriving at its opposite postsynapse, nature of which defines the basic unit of virtual i...

  5. Processing Semblances Induced through Inter-Postsynaptic Functional LINKs, Presumed Biological Parallels of K-Lines Proposed for Building Artificial Intelligence

    OpenAIRE

    Vadakkan, Kunjumon I.

    2011-01-01

    The internal sensation of memory, which is available only to the owner of an individual nervous system, is difficult to analyze for its basic elements of operation. We hypothesize that associative learning induces the formation of functional LINK between the postsynapses. During memory retrieval, the activation of either postsynapse re-activates the functional LINK evoking a semblance of sensory activity arriving at its opposite postsynapse, nature of which defines the basic unit of internal ...

  6. Survey monitoring of environmental radioactivity in Daejeon area

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Jae Shik.; Noh, Hyung Ah [Taejon Radiation Monitoring Station, Daejeon (Korea, Republic of)

    2000-12-15

    Systematic understanding of the distribution of environmental radioactivity and radiation level in Taejon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Taejon Radiation Monitoring Station in 2000. In conclusion, the natural environmental radiation level in Taejon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period.

  7. Survey monitoring of environmental radioactivity in Daejeon area

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Jae Sik; Noh, Hyung Ah [Daejon Radiation Monitoring Station, Daejeon (Korea, Republic of)

    2001-12-15

    Systematic understanding of the distribution of environmental radioactivity and radiation level in Daejeon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Daejeon Radiation Monitoring Station in 2001. In conclusion, the natural environmental radiation level in Daejeon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period.

  8. Radioactive characterization of sand samples from Failaka Island in Kuwait

    International Nuclear Information System (INIS)

    Sand samples were collected from Failaka Island in the state of Kuwait for radioactive characterization. The activity concentrations of both natural and artificial radionuclides were determined using gamma (?)-ray spectrometry. From the measured ?-spectra, radioactivity concentrations were determined for Uranium-238 (238U), Thorium-232 (232Th), Radium-226 (226Ra), Potassium-40 (40K), and Cesium-137 (137Cs). To evaluate the radiological hazard of the natural radioactivity on Failaka Island, the radium equivalent activity, the representative level index, the external hazard index, the internal hazard index, the absorbed dose, and the effective dose rate were calculated and compared with international approved values. (author)

  9. Onion artificial muscles

    Science.gov (United States)

    Chen, Chien-Chun; Shih, Wen-Pin; Chang, Pei-Zen; Lai, Hsi-Mei; Chang, Shing-Yun; Huang, Pin-Chun; Jeng, Huai-An

    2015-05-01

    Artificial muscles are soft actuators with the capability of either bending or contraction/elongation subjected to external stimulation. However, there are currently no artificial muscles that can accomplish these actions simultaneously. We found that the single layered, latticed microstructure of onion epidermal cells after acid treatment became elastic and could simultaneously stretch and bend when an electric field was applied. By modulating the magnitude of the voltage, the artificial muscle made of onion epidermal cells would deflect in opposing directions while either contracting or elongating. At voltages of 0-50 V, the artificial muscle elongated and had a maximum deflection of -30 ?m; at voltages of 50-1000 V, the artificial muscle contracted and deflected 1.0 mm. The maximum force response is 20 ?N at 1000 V.

  10. The use of ?CT and ESEM in the study of the osmosis-induced water uptake by Eurobitum bituminized radioactive waste.

    Science.gov (United States)

    Mariën, An; Valcke, Elie; Bleyen, Nele; Van Geet, Maarten; Wevers, Martine

    2012-10-01

    Laboratory water uptake tests are performed at the Belgian Nuclear Research Centre SCK•CEN to obtain insight into the hydromechanical behavior of Eurobitum bituminized radioactive waste under geological disposal conditions. Small nonradioactive and radioactive Eurobitum samples are hydrated in restricted swelling conditions (i.e., nearly constant volume conditions and constant stress conditions). Microfocus X-ray computer tomography (?CT) proves to be a very suitable technique to follow up the ingress of water in the samples. ?CT analyses demonstrate that, under the studied hydration conditions, the water uptake by Eurobitum samples is a diffusion controlled process. A characterization of the partially leached samples with environmental scanning electron microscopy (ESEM) shows that the hydration of salt crystals and the subsequent dilution of the salt solution result in an increase in pore size that is limited to a few tens of ?m in restricted swelling conditions. The ?CT and ESEM analyses allow improvement in the understanding of water uptake by Eurobitum in restricted swelling conditions. In this article we discuss the ?CT and ESEM analyses of nonradioactive Eurobitum samples that were hydrated for 2 to 4 years at a constant stress of 1, 22, 33, and 44 bar or in nearly constant volume conditions. PMID:23046634

  11. Pregnancy rate in lactating Bos indicus cows subjected to fixed-time artificial insemination and treated with different follicular growth inducers

    Scientific Electronic Library Online (English)

    Ériklis, Nogueira; Dayanna Schiavi do Nascimento, Batista; Luiz Carlos Cesar da, Costa Filho; Alexandre Menezes, Dias; Juliana Corrêa Borges, Silva; Luís Carlos Vinhas, Ítavo.

    2014-07-01

    Full Text Available The objective of this experiment was to evaluate the effects of replacing eCG with FSH or FSH/LH on the diameter of ovulatory follicles (DOF) and the pregnancy rates (PR) of lactating Bos indicus cows subjected to a synchronization of ovulation protocol and fixed-time artificial insemination (FTAI) [...] based on progesterone, estradiol benzoate (EB), PGF2?, and estradiol cypionate (EC). On day 0, primiparous and multiparous Nellore cows (n = 329) at 68 days postpartum were body condition scored (BCS) and received a P4 implant (PRIMER 1.0 g P4) plus 2 mg EB intramuscularly (IM). At day 8, the implant was removed, and 250 ?g cloprostenol were injected IM along with 0.5 mg EC. At the time of implant removal, the animals were divided into one of four treatments: cows received (G1) 1 mL of saline solution IM (Control; n = 80); (G2) 300 IU eCG IM (ECG300; n = 84); (G3) 15 mg FSH IM (Folltropin; n = 82); and (G4) 30 IU FSH/LH IM (Pluset; n = 83); all cows were subjected to FTAI 48-54 h after implant removal (day 10). Transrectal ultrasonography was performed to measure the DOF to FTAI and to estimate the pregnancy rate on day 35. A statistical analysis examined the effects of the treatment, technician, semen, BCS, calf age and parity on PR to FTAI. There was no significant difference in PR and DOF among the treatment groups (G1, 41.3%, 13.1 mm; G2, 46.4%, 14.5 mm; G3, 46.3%, 14.2 mm; and G4, 48.2%, 14.3 mm), but PR was higher in multiparous than in primiparous cows. Commercial FSH solutions (Pluset or Folltropin) do not promote increases in PR or DOF of lactating Nellore cows and are equal to eCG in promoting growth in preovulatory follicles and elevating the PR in Nellore cows with a moderate BCS subjected to a progesterone-based FTAI protocol with EC.

  12. Six-year experiences in the environmental radioactivity monitoring in Taiwan

    International Nuclear Information System (INIS)

    An islandwide network for environmental radioactivity monitoring established in 1974 is described with reference to (1) measurement of radioactive fallout from nuclear testings, (2) environmental monitoring for nuclear power plants and a radioactive waste disposal site, (3) a site specially designated by the government, and (4) installations involving radiation. Naturally occurring and artificial radionuclides are equally emphasized. All significant results are reported and discussed. (H.K.)

  13. Decrease of deposited artificial radioactivity in urban environments

    International Nuclear Information System (INIS)

    The behavior of cesium during the first three years after deposition was investigated with in-situ gamma spectrometry at 48 measuring sites. An evaluation method was developed which allowed determination of retention on asphalt surfaces, the effective depth profile in soils covered with grass, and time factor developments of the gamma dose rate. Two months after deposition, the gamma dose rate on grassy soils amounts to 60% of the dose rate for smooth large-scale surfaces with identical deposition, but without weathering or soil migration. After 3 years this ratio lies at 35%. On asphalt surfaces, however, there was after 2 months only a dose rate of 20% of the dose rate on smooth surfaces without weathering; after 3 years it was only 4%. Environment factors were defined which determined the ratio of dose rates on measuring areas to dose rates on large grassy surfaces. The environment factors are the smaller, the bigger the proportion of asphalt. They are constant as regards the time factor, or they decrease gradually after deposition. Results were approximated analytically. The investigation of tiles showed that there was an activity retention of 30-60% on roofs in Munich following wet deposition of cesium. After 2 years it was still 10-25%. (orig./HP)

  14. Device for measuring bore holes using artificial radio-activity

    International Nuclear Information System (INIS)

    The borehole contains salt water or natural oil. The geophysical borehole measurement is carried out with a probe, which contains a neutron source of fast neutrons and a gamma ray detector screened with samarium oxide. The signals of neutron capture-gamma radiation from the detector from H and Cl are evaluated separately by a pulse height analyser with several channels. (RW)

  15. Natural and artificial radioactivity in soils of forests

    International Nuclear Information System (INIS)

    Levels of 222 Rn, 40 K, 235 U, 226 Ra and 137 Cs were studied in soils of a forest zone located at 3000 m altitude in the central portion of Mexico. the radon concentrations in different soil horizons were determined with solid state nuclear track detectors and the concentrations of 40 K, 235 U, 226 Ra and 137 Cs in soil samples were measured with a gamma spectrometer at low level coupled to a High purity Ge detector. The results indicate differences of a magnitude order in the radon concentrations inside the studied area. The levels of 40 K, 235 U, 226 Ra and 137 Cs are discussed as function of the perturbation grade of the soil and atmospheric pollution. (Author)

  16. Radioactivity in consumer products

    Energy Technology Data Exchange (ETDEWEB)

    Moghissi, A.A.; Paras, P.; Carter, M.W.; Barker, R.F. (eds.)

    1978-08-01

    Papers presented at the conference dealt with regulations and standards; general and biological risks; radioluminous materials; mining, agricultural, and construction materials containing radioactivity; and various products containing radioactive sources.

  17. Studies on the utility of artificial mutations in plant breeding, 16: Gene analysis of male sterility induced in rice [Oryza sativa

    International Nuclear Information System (INIS)

    Eleven male-sterile mutants were induced from a rice variety Sasanishiki by ethyleneimine and ?-ray treatments of seeds. Nine of them produced no pollen grains or only abortive ones and the other two showed extremely low pollen fertilities. The eleven mutants were crossed with the original variety. All F1 hybrids were fertile, i.e., normal in both pollen and seed fertilities. In eight of their F2 progenies, fertile and male-sterile plants segregated in a ratio of 3 to 1, indicating that the male sterility of the eight mutants was controlled by a single recessive gene. In one of the other three, segregation ratio suggested the participation of two recessive genes, while in the remaining two, the number of the genes responsible for male sterility could not be determined. (author)

  18. 4 Radioactive waste disposal

    International Nuclear Information System (INIS)

    Radioactive wastes are classified by the areas of their occurrence, by the level and type of radioactivity and the nature of emitted radiation. Described are spent fuel element storage, processing and long-term burial in geological or iceberg formations and on the sea bottom or under it. Deactivation of radioactive materials uses chemical, physical, physico-chemical and biological methods. The question is discussed of the disposal of radioactive gases and aerosols as is that of nuclear reactor decommissioning. (J.C.)

  19. Radioactive waste management

    International Nuclear Information System (INIS)

    This booklet is a publication by International Atomic Energy Agency for general awareness of citizens and policy-makers to clarify their concept of nuclear wastes. In a very simple way it tells what is radioactivity, radiations and radioactive wastes. It further hints on various medial and industrial uses of radiations. It discusses about different types of radioactive wastes and radioactive waste management. Status of nuclear power plants in Central and Eastern European countries are also discussed

  20. Radioactive tracers in the sea

    International Nuclear Information System (INIS)

    Artificial radionuclides introduced to the oceans during the last four decades have proved invaluable tools for study of many processes in marine water columns and sediments. Both global and close-in fallout of radioactivity from atmospheric nuclear weapons testing have distributed these radionuclides widely, and in amounts sufficient to be useful as tracers. An additional source of considerable significance and tracer potential comes from coastal discharges of European nuclear fuel reprocessing wastes. The nature of these sources, types and amounts of radionuclides introduced and the time histories of their introduction generate a variety of tracer distributions which illuminate a broad spectrum of physical and chemical processes active over a wide range of timescales. Depending on their respective chemistries, artificial radionuclides have been demonstrated to exhibit both conservative and non-conservative properties in the oceans. Some examples are given of the uses made of soluble, conservative tracers for the study of oceanic transport processes and of non-conservative tracers for studies of processes which move them to, and mix them within, marine sediments. Sampling and measurement techniques which have been used in these studies are described

  1. Radioactive waste management

    International Nuclear Information System (INIS)

    Notes provided for teachers, students and environmentalists give background information on radioactive isotopes, radiation doses, risks of radiation damage. Radioactive wastes are categorised and present waste disposal procedures are described. Methods of safeguarding the population when radioactive wastes are disposed of in the environment are discussed. Discussion topics are presented. (UK)

  2. Understanding radioactive waste

    International Nuclear Information System (INIS)

    This book discusses the sources and health effects of radioactive wastes. It reveals the techniques to concentrate and immobilize radioactivity and examines the merits of various disposal ideas. The book, which is designed for the lay reader, explains the basic science of atoms,nuclear particles,radioactivity, radiation and health effects

  3. Bibliography: Artificial Intelligence.

    Science.gov (United States)

    Smith, Richard L.

    1986-01-01

    Annotates reference material on artificial intelligence, mostly at an introductory level, with applications to education and learning. Topics include: (1) programing languages; (2) expert systems; (3) language instruction; (4) tutoring systems; and (5) problem solving and reasoning. (JM)

  4. Artificial Disc Replacement

    Science.gov (United States)

    ... artificial disc (also called a disc replacement, disc prosthesis or spine arthroplasty device) is a device that ... usually made of metal or plastic-like (biopolymer) materials, or a combination of the two. These materials ...

  5. Artificial Hydration and Nutrition

    Science.gov (United States)

    ... about the patient's medical condition and risks and benefits of giving artificial hydration and nutrition. Each situation is different. Your doctor ... Withholding and Withdrawing Life-Sustaining Treatment by RJ Ackermann, M.D. (American Family Physician ...

  6. The Artificial Regression Market

    OpenAIRE

    Lay, Nathan; Barbu, Adrian

    2012-01-01

    The Artificial Prediction Market is a recent machine learning technique for multi-class classification, inspired from the financial markets. It involves a number of trained market participants that bet on the possible outcomes and are rewarded if they predict correctly. This paper generalizes the scope of the Artificial Prediction Markets to regression, where there are uncountably many possible outcomes and the error is usually the MSE. For that, we introduce the reward kern...

  7. Artificial Intelligence in Games

    OpenAIRE

    Raju; Nitin Sikka; Sanjeev Kumar; Rahul Gupta

    2012-01-01

    Based on the recent surge in interest in the both academic and games industry in character- based artificial intelligence. Although the games are mainly related with entertainments, but with this there are other serious applications of gaming, including military training, educational games, driving training, medical training and games that reflect social consciousness or advocate for a cause. Artificial intelligence in games is a concept of taking game applications beyond the lim...

  8. Artificial intelligence in medicine.

    OpenAIRE

    Ramesh, A. N.; C. Kambhampati; Monson, J R T; Drew, P. J.

    2004-01-01

    INTRODUCTION: Artificial intelligence is a branch of computer science capable of analysing complex medical data. Their potential to exploit meaningful relationship with in a data set can be used in the diagnosis, treatment and predicting outcome in many clinical scenarios. METHODS: Medline and internet searches were carried out using the keywords 'artificial intelligence' and 'neural networks (computer)'. Further references were obtained by cross-referencing from key articles. An overview of ...

  9. Physics of Artificial Gravity

    Science.gov (United States)

    Bukley, Angie; Paloski, William; Clement, Gilles

    2006-01-01

    This chapter discusses potential technologies for achieving artificial gravity in a space vehicle. We begin with a series of definitions and a general description of the rotational dynamics behind the forces ultimately exerted on the human body during centrifugation, such as gravity level, gravity gradient, and Coriolis force. Human factors considerations and comfort limits associated with a rotating environment are then discussed. Finally, engineering options for designing space vehicles with artificial gravity are presented.

  10. Intelligence: Real or artificial?

    OpenAIRE

    Schlinger, Henry D

    1992-01-01

    Throughout the history of the artificial intelligence movement, researchers have strived to create computers that could simulate general human intelligence. This paper argues that workers in artificial intelligence have failed to achieve this goal because they adopted the wrong model of human behavior and intelligence, namely a cognitive essentialist model with origins in the traditional philosophies of natural intelligence. An analysis of the word “intelligence” suggests that it originally r...

  11. Principles of artificial intelligence

    CERN Document Server

    Nilsson, Nils J

    1980-01-01

    A classic introduction to artificial intelligence intended to bridge the gap between theory and practice, Principles of Artificial Intelligence describes fundamental AI ideas that underlie applications such as natural language processing, automatic programming, robotics, machine vision, automatic theorem proving, and intelligent data retrieval. Rather than focusing on the subject matter of the applications, the book is organized around general computational concepts involving the kinds of data structures used, the types of operations performed on the data structures, and the properties of th

  12. Artificial Body Voices

    OpenAIRE

    Unander-Scharin, Carl; Unander-Scharin, Åsa

    2011-01-01

    Artificial Body Voices, 25-27 november 2011 Studio Acusticum i Piteå   I Artificial Body Voices stiger publiken in i en mytopoetisk värld för att möta fantasieggande hybridvarelser, en dansande robotsvan, pulserande musik, underskön sång, en interaktiv röstmaskin och tretton dansare omslutna av videoanimationer som slingrande rör sig över väggar och golv. Vi vill inbjuda publiken till ett lekfullt experimentarium som undersöker människans längtan och drift att med teknologin omskapa, förändra...

  13. Spatially Resolved Artificial Chemistry

    DEFF Research Database (Denmark)

    Fellermann, Harold

    2009-01-01

    Although spatial structures can play a crucial role in chemical systems and can drastically alter the outcome of reactions, the traditional framework of artificial chemistry is a well-stirred tank reactor with no spatial representation in mind. Advanced method development in physical chemistry has made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical model...

  14. Heidegger and artificial intelligence

    Energy Technology Data Exchange (ETDEWEB)

    Diaz, G.

    1987-01-01

    The discipline of Artificial Intelligence, in its quest for machine intelligence, showed great promise as long as its areas of application were limited to problems of a scientific and situation neutral nature. The attempts to move beyond these problems to a full simulation of man's intelligence has faltered and slowed it progress, largely because of the inability of Artificial Intelligence to deal with human characteristic, such as feelings, goals, and desires. This dissertation takes the position that an impasse has resulted because Artificial Intelligence has never been properly defined as a science: its objects and methods have never been identified. The following study undertakes to provide such a definition, i.e., the required ground for Artificial Intelligence. The procedure and methods employed in this study are based on Heidegger's philosophy and techniques of analysis as developed in Being and Time. Results of this study show that both the discipline of Artificial Intelligence and the concerns of Heidegger in Being and Time have the same object; fundamental ontology. The application of Heidegger's conclusions concerning fundamental ontology unites the various aspects of Artificial Intelligence and provides the articulation which shows the parts of this discipline and how they are related.

  15. Artificial skin. Jinko hifu

    Energy Technology Data Exchange (ETDEWEB)

    Kifune, K. (Unitika Ltd., Osaka (Japan))

    1993-06-15

    In order to restore the human skin wounds, the transplantation is only one measure. The transplantation can take only when own skin is used, and there is no successful example by using other person's skin. When the own skin is not sufficient due to the too vast damage, the artificial skin, which can be regenerated as it is, is required. The artificial skin is said to be the most difficult organ among the artificial organs, even though its function is quite simple. Although there are the pig skin, the collagen membrane and the synthetic materials such as the polyurethane and so forth, as the materials similar to the artificial skin, they cover the wounds just until the cuticle is formed. Recently there is a cultivated skin. Firstly the normal skin with a size of the stamp is cut off, and then the cuticle cells are taken to pieces and cultivated, and consequently it is possible to increase the area by several 10 times. In addition, there is also a trial to make the artificial skin synthetically. Its upper layer is composed of the silicon, and the lower layer is the collagen membrane with a sponge structure. The silicon, membrane can be said to be an ideal artificial skin, because it detaches naturally. The chitin, which has recently appeared as the wound protection material, is also the promising material. 3 figs.

  16. Penetration by artificial electron acceptors of the plasma membrane-bound redox system into intact Zea mays L. roots investigated by proton-induced X-ray emission

    International Nuclear Information System (INIS)

    Proton-induced X-ray emission was used to investigate the penetration of compounds of the membrane-impermeant electron acceptors hexabromoiridate IV, hexachloroiridate IV, and hexacyanoferrate III into corn (Zea mays L.) roots. Maps of the heavy element distribution in cross-sections of fixed, epoxy-embedded roots showed for hexabromoiridate IV small amounts of Br in samples treated for 24 h with concentrations normally used in physiological experiments (0.02 mM). After treatment with high concentrations (0.8 mM) of these complexes, Fe and Ir as well as Br were found in root cross-sections. In samples taken at a distance of 5 mm behind the root tip, we found an even distribution of Fe, Ir, and Br over the whole cross-section. In samples taken 15 mm behind the root tip, about 99% of both Br and Ir was confined to the rhizodermal cell layer. The distribution did not change with the complex used. These data are consistent with the view that apoplastic diffusion of the electron acceptors was blocked by the hypodermal Casparian band

  17. Induced radioactivity in air-estimation of ventilation rates at the vault and experimental areas of the proposed K-500 superconducting cyclotron, Calcutta

    International Nuclear Information System (INIS)

    Guidelines are given for the necessary ventilation rates in vault and experimental areas from radiological safety point of view, for the proposed K-500 super-conducting cyclotron at Calcutta. A method is presented for estimating the amount of short lived radioisotopes like 13N and 15O taking the (n,2n) mode of productions. Considering the operating conditions of K-500 machine for the production of maximum neutron flux (300 MeV, 50pnA Li beam on Ta target) the energy differential neutron flux and the energy differential production cross section of 13N and 15O have been generated using ALICE-91 computer code. The differential cross sections have been folded with radial neutron flux distribution and then integrated over the entire volume of the cyclotron vault, to obtain the total production of the two radioactive gases. The DAC values have been obtained by considering the immersion dose in a semi-infinite hemispherical cloud. Natural decay and removal due to ventilation have been considered to get the recommended ventilation rates. (author)

  18. The radioactive inventory of a decommissioned magnox power station structure. 1. Measurements of neutron induced activity in samples from the reactor island

    International Nuclear Information System (INIS)

    This report is the first of a series which, together, aim to produce an accurate assessment of neutron induced activation levels in the fixed structural components of a reactor of the steel pressure vessel Magnox type. It describes the measurements made of induced activation, necessary in order to establish credibility in the complex calculations described in the subsequent reports. The report also attempts systematically to assess the potential contributions to the dose and disposal problem from all isotopes with a half-life in excess of 5 years. This is necessary in order to ensure that no isotope has been overlooked which could limit any part of the plan for the decommissioning of a Magnox reactor. In addition the report aims to determine concentrations, in each major material type, of trace elements which lead to the isotopes limiting in decommissioning. (author)

  19. Radioactive and chemotoxic wastes: Only radioactive wastes?

    International Nuclear Information System (INIS)

    Radioactive waste arising from Italian Nuclear Power Plants and Research Centers, classified as 1st and 2nd Category wastes, are managed only as radioactive wastes following the Technical Guide No. 26 issued by the Italian Regulatory Body: ENEA DISP on 1987. A very important Regulatory Regime revision for Italian Nuclear Activities started at the end of 1991. This paper considers the need to develop a new strategy dedicated to mixed waste in line with current international trends

  20. A survey of radioactive levels of agricultural products in Saitama prefecture

    International Nuclear Information System (INIS)

    Past atmospheric nuclear testing which have been conducted frequently, have caused environmental pollution due to the diffusion of radioactive substances into the atmosphere and from the radioactive fallout. The environmental pollution from nuclear testing into the atmosphere has resulted in the radioactive contamination in agricultural products and has continued for a long time. The radioactive contamination of agricultural products occurs through air, water and soil which were contaminated by radioactive fallout. In this paper, for the purpose of analyzing the extent of the radioactive contamination levels in the agricultural products of Saitama Prefecture, spinach, green soybeans, dried shiitake and welsh onion, were selected among products, as the amount of the harvest is abundant in all of Japan. Radioactivity concentration was investigated by gamma-ray spectrometry and radiochemical analysis. The radioactivity concentrations of artificial radioactive nuclides, cesium-137 (137Cs) and strontium-90 (90Sr), were detected in the range which is considered to be the result of radioactive fallout. Moreover, in order to examine the effect on radioactivity concentrations in agricultural products by culinary processing, the raw agricultural products were boiled, and their radioactivity concentrations were compared with the raw produce. The radioactivity concentrations in the boiled were lower than those in the raw produce. (author)

  1. Artificial Intelligence in Games

    Directory of Open Access Journals (Sweden)

    Raju

    2012-11-01

    Full Text Available Based on the recent surge in interest in the both academic and games industry in character- based artificial intelligence. Although the games are mainly related with entertainments, but with this there are other serious applications of gaming, including military training, educational games, driving training, medical training and games that reflect social consciousness or advocate for a cause. Artificial intelligence in games is a concept of taking game applications beyond the limits of interactive gaming. Such system learn about the player’s behaviours during game play and beyond the pre-programmed set provides and interactively develop and provide a best experience to the players.General Terms The main aim of our research is to develop such artificial intelligence techniques that can have a substantial impact in the game industry. In the following research paper we are going to study about Case Based Reasoning (CBR, automatic behaviour adjustment for believing characters, drama management and user modelling for interactive stories and strategic behaviour planning for real time strategy games. We include problems in adopting artificial intelligence in games and some algorithms for respective games. Future aspect of artificial intelligence in games is also mentioned in the paper.

  2. Radioactivity Monitoring of the Irish Environment 2010-2011

    International Nuclear Information System (INIS)

    This report presents the results of the environmental radioactivity monitoring programme carried out by the Radiological Protection Institute of Ireland RPII during 2010 and 2011. The RPII has routinely monitored levels of radioactivity in the Irish environment since 1982 and this is the latest in the RPII's series of environmental monitoring reports. The RPII reviews and updates its environmental programme annually to ensure it remains relevant and continues to focus on the most important sources of radioactivity in the environment. The data presented in this report confirm that while the levels of artificial radioactivity in the Irish environment are detectable, they are low. They do not pose a significant risk to the human health of the Irish population. Trace amounts of radioactive isotopes consistent with the Fukushima nuclear accident were detected in air, rainwater and milk samples during the period March to May 2011. These increases in levels of radioactivity were not of concern from a public health point of view. For the remainder of the reporting period, activity concentrations of radionuclides in airborne particles were low and consistent with measurements made in recent years. Radioactivity levels in milk, mixed diet and a wide range of foodstuffs were low and, for the majority of samples, below the detection limits. All drinking waters tested were found to be in compliance with the total indicative dose defined in national and EU legislation. The doses incurred by the Irish public in 2010 and 2011 as a result of artificial radioactivity in the marine environment are small when compared to dose limits or to natural radiation doses received by the Irish public. The doses to the most exposed individuals, members of the oyster and mussel farmers critical group, were approximately 0.02 per cent and 0.05 per cent of the annual dose limit of 1000 microsieverts for members of the public from practices involving controllable sources of radiation in 2010 and 2011 respectively. The increase in 2011 can be attributed to changes in sampling protocol and analytical method. These doses represent a small fraction of the average annual dose to a person in Ireland from all sources of radioactivity of 3950 microsieverts. In general, levels of artificial radioactivity in the Irish environment remain fairly constant and are broadly consistent with levels reported previously. It must be emphasised that the levels of radioactive contamination present in the marine environment, do not warrant any modification of the habits of people in Ireland, either in respect of consumption of seafood or any other use of the amenities of the marine environment

  3. Rutherford, Radioactivity, and the Atomic Nucleus

    CERN Document Server

    Kragh, Helge

    2012-01-01

    Modern atomic and nuclear physics took its start in the early part of the twentieth century, to a large extent based upon experimental investigations of radioactive phenomena. Foremost among the pioneers of the new kind of physics was Ernest Rutherford, who made fundamental contributions to the structure of matter for more than three decades and, in addition, founded important research schools in Manchester and Cambridge. This paper reviews the most important aspects of Rutherford's scientific work in the period from about 1900 to 1920, and it also refers to some of his last experiments of the 1930s. The emphasis is on his theory of radioactive disintegration (1902), the discovery of the atomic nucleus (1911), and the first artificially produced element transformation (1919). Following the transmutation experiments, Rutherford developed elaborate models of the atomic nucleus, but these turned out to be unsuccessful. Other subjects could be included, but the three mentioned are undoubtedly those of the greates...

  4. Artificial intelligence in nanotechnology

    Science.gov (United States)

    Sacha, G. M.; Varona, P.

    2013-11-01

    During the last decade there has been increasing use of artificial intelligence tools in nanotechnology research. In this paper we review some of these efforts in the context of interpreting scanning probe microscopy, the study of biological nanosystems, the classification of material properties at the nanoscale, theoretical approaches and simulations in nanoscience, and generally in the design of nanodevices. Current trends and future perspectives in the development of nanocomputing hardware that can boost artificial-intelligence-based applications are also discussed. Convergence between artificial intelligence and nanotechnology can shape the path for many technological developments in the field of information sciences that will rely on new computer architectures and data representations, hybrid technologies that use biological entities and nanotechnological devices, bioengineering, neuroscience and a large variety of related disciplines.

  5. Artificial intelligence in nanotechnology

    International Nuclear Information System (INIS)

    During the last decade there has been increasing use of artificial intelligence tools in nanotechnology research. In this paper we review some of these efforts in the context of interpreting scanning probe microscopy, the study of biological nanosystems, the classification of material properties at the nanoscale, theoretical approaches and simulations in nanoscience, and generally in the design of nanodevices. Current trends and future perspectives in the development of nanocomputing hardware that can boost artificial-intelligence-based applications are also discussed. Convergence between artificial intelligence and nanotechnology can shape the path for many technological developments in the field of information sciences that will rely on new computer architectures and data representations, hybrid technologies that use biological entities and nanotechnological devices, bioengineering, neuroscience and a large variety of related disciplines. (topical review)

  6. Artificial muscles on heat

    Science.gov (United States)

    McKay, Thomas G.; Shin, Dong Ki; Percy, Steven; Knight, Chris; McGarry, Scott; Anderson, Iain A.

    2014-03-01

    Many devices and processes produce low grade waste heat. Some of these include combustion engines, electrical circuits, biological processes and industrial processes. To harvest this heat energy thermoelectric devices, using the Seebeck effect, are commonly used. However, these devices have limitations in efficiency, and usable voltage. This paper investigates the viability of a Stirling engine coupled to an artificial muscle energy harvester to efficiently convert heat energy into electrical energy. The results present the testing of the prototype generator which produced 200 ?W when operating at 75°C. Pathways for improved performance are discussed which include optimising the electronic control of the artificial muscle, adjusting the mechanical properties of the artificial muscle to work optimally with the remainder of the system, good sealing, and tuning the resonance of the displacer to minimise the power required to drive it.

  7. An artificial molecular pump

    Science.gov (United States)

    Cheng, Chuyang; McGonigal, Paul R.; Schneebeli, Severin T.; Li, Hao; Vermeulen, Nicolaas A.; Ke, Chenfeng; Stoddart, J. Fraser

    2015-06-01

    Carrier proteins consume fuel in order to pump ions or molecules across cell membranes, creating concentration gradients. Their control over diffusion pathways, effected entirely through noncovalent bonding interactions, has inspired chemists to devise artificial systems that mimic their function. Here, we report a wholly artificial compound that acts on small molecules to create a gradient in their local concentration. It does so by using redox energy and precisely organized noncovalent bonding interactions to pump positively charged rings from solution and ensnare them around an oligomethylene chain, as part of a kinetically trapped entanglement. A redox-active viologen unit at the heart of a dumbbell-shaped molecular pump plays a dual role, first attracting and then repelling the rings during redox cycling, thereby enacting a flashing energy ratchet mechanism with a minimalistic design. Our artificial molecular pump performs work repetitively for two cycles of operation and drives rings away from equilibrium toward a higher local concentration.

  8. An artificial molecular pump.

    Science.gov (United States)

    Cheng, Chuyang; McGonigal, Paul R; Schneebeli, Severin T; Li, Hao; Vermeulen, Nicolaas A; Ke, Chenfeng; Stoddart, J Fraser

    2015-06-01

    Carrier proteins consume fuel in order to pump ions or molecules across cell membranes, creating concentration gradients. Their control over diffusion pathways, effected entirely through noncovalent bonding interactions, has inspired chemists to devise artificial systems that mimic their function. Here, we report a wholly artificial compound that acts on small molecules to create a gradient in their local concentration. It does so by using redox energy and precisely organized noncovalent bonding interactions to pump positively charged rings from solution and ensnare them around an oligomethylene chain, as part of a kinetically trapped entanglement. A redox-active viologen unit at the heart of a dumbbell-shaped molecular pump plays a dual role, first attracting and then repelling the rings during redox cycling, thereby enacting a flashing energy ratchet mechanism with a minimalistic design. Our artificial molecular pump performs work repetitively for two cycles of operation and drives rings away from equilibrium toward a higher local concentration. PMID:25984834

  9. Regions with increased natural radioactivity. Pt. 3

    International Nuclear Information System (INIS)

    The goals pursued by the investigation on hand were: 1. to get a survey of natural radioactivity in the Fichtelgebirge; 2. to find and describe locally restricted areas of high natural radioactivity (abnormal radiation, hot spots); this will be a starting point 3. for the assessment of possible increased radiation exposure and of the state of health of a restricted number of persons. Furthermore, there are also 4. underground data for the eventual stipulation of maximum permissible values for natural radioactivity. 5. The situation in the Fichtelgebirge shall be compared with that of the monazite sand-stone areas in India. The highest gamma dose rates measured in locally restricted areas were: 1. granite road pavement: 24 ?R/h; 2. granite quarries (35 ?R/h); 3. caves below granite rock (40 to 70 ?R/h); 4. slag brick pavement on market place and main street of Marktredwitz (53.4 ?R/h) (part of which removed already); 5. uranium abnormalities on a farmer's field (80-100 ?R/h) (0.6 m below the surface: 1.500 ?R/h); this may be considered an uranium deposit with a content in uranium of up to 0.3%; 6. over 100 ?R/h in front of an uranium ore mine in the uranium prospection drift (rest of the drift in the granite no more than 29.3+-3.3 ?R/h). The resulting maximum conceivable radiation exposure is assessed. The question whether there is a necessity for setting tolerance limit values for natural radioactivity is raised again; the magnitude in comparison with limit values for artificial radioactivity in radioactive controlled areas is pointed out. (orig./HP)

  10. Survey monitoring of environmental radioactivity in Daegu area

    Energy Technology Data Exchange (ETDEWEB)

    Kang, H. D.; Lee, S. Y. [Kyungpook National Univ., Daegu (Korea, Republic of)

    1998-01-15

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

  11. Artificial ionospheric turbulence (review)

    International Nuclear Information System (INIS)

    This study is an analysis of artificial ionospheric turbulence (AIT) arising near the level at which a powerful wave is reflected with ordinary polarization. AIT is an inhomogeneous structure in the ionosphere with a size on the order of centimeters or tens of kilometers and with characteristic frequencies from a fraction of a hertz (aperiodic inhomogeneity) to several megahertz (plasma waves). The authors are primarily concerned with small-scale artificial ionospheric turbulence (SAIT), i.e., with inhomogeneities that are greatly extended along the geomagnetic field with transverse dimensions that are less than the wavelengths of the perturbing waves - the pumping waves (PW) - in a vacuum

  12. Bayesian artificial intelligence

    CERN Document Server

    Korb, Kevin B

    2003-01-01

    As the power of Bayesian techniques has become more fully realized, the field of artificial intelligence has embraced Bayesian methodology and integrated it to the point where an introduction to Bayesian techniques is now a core course in many computer science programs. Unlike other books on the subject, Bayesian Artificial Intelligence keeps mathematical detail to a minimum and covers a broad range of topics. The authors integrate all of Bayesian net technology and learning Bayesian net technology and apply them both to knowledge engineering. They emphasize understanding and intuition but also provide the algorithms and technical background needed for applications. Software, exercises, and solutions are available on the authors' website.

  13. Artificial intelligence executive summary

    International Nuclear Information System (INIS)

    Artificial intelligence (AI) is a high technology field that can be used to provide problem solving diagnosis, guidance and for support resolution of problems. It is not a stand alone discipline, but can also be applied to develop data bases for retention of the expertise that is required for its own knowledge base. This provides a way to retain knowledge that otherwise may be lost. Artificial Intelligence Methodology can provide an automated construction management decision support system, thereby restoring the manager's emphasis to project management

  14. Shielding experiments by the JASMIN collaboration at Fermilab (II) - Radioactivity measurement induced by secondary particles from the anti-proton production target

    Energy Technology Data Exchange (ETDEWEB)

    Yashima, Hiroshi; /Kyoto U., KURRI; Matsuda, Norihiro; Kasugai, Yoshimi; /JAEA, Ibaraki; Matsumura, Hiroshi; Iwase, Hiroshi; /KEK, Tsukuba; Kinoshita, Norikazu; /KEK, Tsukuba /Tsukuba U.; Boehnlein, David; Lauten, Gary; Leveling, Anthony; Mokhov, Nikolai; Vaziri, Kamran; /Fermilab /Shimizu, Tokyo /JAEA, Ibaraki

    2011-01-01

    The JASMIN Collaboration has performed an experiment to conduct measurements of nuclear reaction rates around the anti-proton production (Pbar) target at the Fermi National Accelerator Laboratory (FNAL). At the Pbar target station, the target, consisting an Inconel 600 cylinder, was irradiated by a 120 GeV/c proton beam from the FNAL Main Injector. The beam intensity was 3.6 x 10{sub 12} protons per second. Samples of Al, Nb, Cu, and Au were placed near the target to investigate the spatial and energy distribution of secondary particles emitted from it. After irradiation, the induced activities of the samples were measured by studying their gamma ray spectra using HPGe detectors. The production rates of 30 nuclides induced in Al, Nb, Cu, Au samples were obtained. These rates increase for samples placed in a forward (small angle) position relative to the target. The angular dependence of these reaction rates becomes larger for increasing threshold energy. These experimental results are compared with Monte Carlo calculations. The calculated results generally agree with the experimental results to within a factor of 2 to 3.

  15. Evaluation of Artificial Intelligence Based Models for Chemical Biodegradability Prediction

    OpenAIRE

    Aleksandar Sabljic; Mihelcic, James R; Dragan Gamberger; Baker, James R

    2004-01-01

    This study presents a review of biodegradability modeling efforts including a detailed assessment of two models developed using an artificial intelligence based methodology. Validation results for these models using an independent, quality reviewed database, demonstrate that the models perform well when compared to another commonly used biodegradability model, against the same data. The ability of models induced by an artificial intelligence methodology to accommodate complex interactions in ...

  16. Biokinetics of radioactive compounds

    International Nuclear Information System (INIS)

    Biokinetics of radioactive compounds in the human organism represent the central notion in this work, consisting of a theoretical and an experimental part. The first chapter contains definitions and explanations on the importance of the biokinetics of radioactive compounds in clinical therapy and pharmaceuticals research as well as for assessing radiation exposure and radiation hazards. Chapter 2 describes the bases of the biokinetics of radioactive compounds in the medical and non-medical sector, and biokinetics. Chapter 3 deals with obtaining biokinetics data for radioactive compounds from investigations in animals and man, evaluation of measurements, transferring data obtained by animal experiments to man, and with the variability of biokinetics data. In Chapter 4 the results of comprehensive studies in literature on the biokinetics of radioactive compounds are summarized. They relate to three areas: professional and environmental incorporation of radioactive compounds, use of radioactive pharmaceuticals in therapy and research, and incorporation of radioactive compounds by embryo and fetus in consequence of the uptake of radioactive compounds by the mother. Chapter 5 gives an assessment of radiation hazards from radioactive compounds in connection with occupational radiation exposure and nuclear diagnostics in vivo, and a comparison with other risks. For that purpose the concept of effective dose equivalent is applied in connection with suitable risk coefficients to professional and nuclear-medical radiation exposure. Chapter 6 is dedicated to measurement of the biokinetics of radioactive compounds in man using conventional devices. The object of Chapter 7 is measurement of the biokinetics of radioactive pharmaceuticals in man by means of single photon emission computed tomography. (orig./MG)

  17. Disposal of radioactive wastes

    International Nuclear Information System (INIS)

    The meeting which was organized by Bundesamt fuer Strahlenschutz and took place on November 25 and 26, 1991 in Berlin informed the plant owners liable to delivery, the nuclear waste conditioners, and the nuclear licensing and supervisory boards in the five new provinces of unified Germany on the disposal of radioactive wastes. Emphasis was placed on the radioactive waste acceptance requirements, waste package quality control, safety aspects relevant to the Morsleben repository, and on the conditioning and intermediate storage of radioactive wastes. (BBR)

  18. Radioactivity and its measurement

    CERN Document Server

    Mann, W B; Garfinkel, S B

    1980-01-01

    Begins with a description of the discovery of radioactivity and the historic research of such pioneers as the Curies and Rutherford. After a discussion of the interactions of &agr;, &bgr; and &ggr; rays with matter, the energetics of the different modes of nuclear disintegration are considered in relation to the Einstein mass-energy relationship as applied to radioactive transformations. Radiation detectors and radioactivity measurements are also discussed

  19. Radio-ecological aspects in artificial groundwater recharge

    International Nuclear Information System (INIS)

    In increasing extent surface waters, especially those of rivers and streams, are contaminated by radionuclides. Therefore it is necessary to investigate the possibility of impairement of the quality of artificially recharged groundwater and drinking water by radionuclides. Hazards for man are possible by drinking water, that was affected by waste and during exposition to air, as well as indirectly by irrigation water and the food chain. In a model calculation using realistic conditions the order of magnitude of these hazards for man by incorporation of radioactively contaminated artificially recharged drinking water are to be assessed. Here the parameters are discussed which must be considered in such an assessment. The model includes the use of river water for artificial recharge. All models and assessments assume the most unfavourable preconditions, which may lead to an impact to man. (orig.)

  20. Transporting radioactive material

    International Nuclear Information System (INIS)

    To be used, radioactive material must first be transported---from its source to processing and manufacturing facilities, to users, and, eventually, to storage and disposal sites. These materials are shipped as solids, liquids, or gases and vary widely in their radioactive nature. Over 3 million packages of radioactive material are shipped each year in the United States. These shipments are carried by government or commercial conveyances such as trucks, trains, ships, and airplanes. Radioactive material is transported on our highways, waterways, railroads, and by air, just like other commodities. Radioactive material can be safely shipped in everyday commerce. Proper packaging is the key. Strict compliance with stringent regulations is required in the packaging of radioactive material to ensure that the public and the environment are protected even in case of a severe accident. There have been no deaths or even any serious injuries resulting from the radioactive nature of the cargo shipped. To extend that exemplary safety record, strict enforcement of US Department of Transportation regulations and research continue. The regulations are reviewed routinely to ensure the protection of public health and safety. People are understandably concerned about how a shipment of radioactive material might affect them, their families, and their environment. This booklet briefly answers commonly asked questions about the transport of radioactive material to put these concerns in perspective. More detailed information is available from many sources. Some of these sources are listed at the end of this booklet

  1. Radioactive waste in perspective

    CERN Document Server

    2010-01-01

    Large volumes of hazardous wastes are produced each year, however only a small proportion of them are radioactive. While disposal options for hazardous wastes are generally well established, some types of hazardous waste face issues similar to those for radioactive waste and also require long-term disposal arrangements. The objective of this NEA study is to put the management of radioactive waste into perspective, firstly by contrasting features of radioactive and hazardous wastes, together with their management policies and strategies, and secondly by examining the specific case of the wastes

  2. Radioactive Waste Management Basis

    Energy Technology Data Exchange (ETDEWEB)

    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.

  3. Radioactive gas measuring device

    International Nuclear Information System (INIS)

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

  4. Controlling radioactive waste

    International Nuclear Information System (INIS)

    The guideline of the Ministry for Environmental Protection for controlling radioactive waste with a negligible development of heat defines in detail what data are relevant to the control of radioactive waste and should be followed up on and included in a system of documentation. By introducing the AVK (product control system for tracing the course of waste disposal) the operators of German nuclear power plants have taken the requirements of this guideline into account. In particular, possibilities for determining the degree of radioactivity of radioactive waste, which the BMU-guidelines call for, were put into practice by means of the programming technology of the product control system's module MOPRO. (orig.)

  5. Stress and radioactive waste management

    International Nuclear Information System (INIS)

    In the Supreme Court case ''People Against Nuclear Energy (PANE) vs Metropolitan Edison,'' one of the conclusions was that the Nuclear Regulatory Commission did not have to consider psychological distress, community cohesiveness and sense of well-being in the supplement to the Environmental Impact Statement (EIS) covering the restart of Three Mile Island (TMI). This decision was based on the assumption that the intention of the National Environmental Policy Act (NEPA) is to focus on the physical environment, and the casual chain between psychological distress and adverse health effects is tenuous. In this paper the authors summarize the literature on the relationship between environmentally-induced stress and its effects on health. They present the results of a new survey research project in which levels of stress were evaluated in West Chicago, Illinois, a community in which radioactive wastes have been present for many years. Explanatory social variables are brought into the evaluation in which stress is evaluated as a function of proximity to the radioactive waste site. In addition, stress is discussed in the context of attitudes on nuclear power, environmental group participation, and knowledge about the health effects associated with radioactive waste. The paper ends with a discussion of the portion of the Supreme Court decision in which psychological distress, community stability, cohesiveness and sense of well being are excluded as variables to address in EISs

  6. Characteristics and Disposal Categorization of Solid Radioactive Waste from the Front End of the Uranium Fuel Cycle

    International Nuclear Information System (INIS)

    The proper categorization of radioactive waste forms the basis for defining its disposal method. In particular, it is the basis for defining the disposal policy for solid radioactive waste from the front end of the uranium fuel cycle to identify scientifically its characteristics, in view of the differences in regulatory approach between artificial radioactive waste and NORM waste. The paper examines the disposal policy and practice in China and other countries for solid radioactive waste from the front end of the uranium fuel cycle and discusses the confusion in disposal of the waste as artificial radioactive waste. The radionuclide composition and characteristics of the solid radioactive waste from the front end of the uranium fuel cycle are investigated in detail and a new idea that such waste needs to be disposed of and categorized as NORM waste is proposed. (author)

  7. Medicare Coverage: Orthotics & Artificial Limbs

    Science.gov (United States)

    ... covered? Search Medicare.gov for covered items Orthotics & artificial limbs & eyes How often is it covered? Medicare ... go to a supplier that’s enrolled in Medicare Artificial limbs and eyes Arm, leg, back, and neck ...

  8. Inflatable artificial sphincter - series (image)

    Science.gov (United States)

    An artificial urinary sphincter is used to treat stress incontinence in men that is caused by urethral dysfunction such ... An artificial sphincter consists of three parts: a cuff that fits around the bladder neck a pressure regulating balloon ...

  9. Evaluation of Terrorist Interest in Radioactive Wastes

    International Nuclear Information System (INIS)

    Since September 11, 2001, intelligence gathered from Al Qaeda training camps in Afghanistan, and the ensuing terrorist activities, indicates nuclear material security concerns are valid. This paper reviews available information on sealed radioactive sources thought to be of interest to terrorists, and then examines typical wastes generated during environmental management activities to compare their comparative 'attractiveness' for terrorist diversion. Sealed radioactive sources have been evaluated in numerous studies to assess their security and attractiveness for use as a terrorist weapon. The studies conclude that tens of thousands of curies in sealed radioactive sources are available for potential use in a terrorist attack. This risk is mitigated by international efforts to find lost and abandoned sources and bring them under adequate security. However, radioactive waste has not received the same level of scrutiny to ensure security. This paper summarizes the activity and nature of radioactive sources potentially available to international terrorists. The paper then estimates radiation doses from use of radioactive sources as well as typical environmental restoration or decontamination and decommissioning wastes in a radioactive dispersal device (RDD) attack. These calculated doses indicate that radioactive wastes are, as expected, much less of a health risk than radioactive sources. The difference in radiation doses from wastes used in an RDD are four to nine orders of magnitude less than from sealed sources. We then review the International Atomic Energy Agency (IAEA) definition of 'dangerous source' in an adjusted comparison to common radioactive waste shipments generated in environmental management activities. The highest waste dispersion was found to meet only category 1-3.2 of the five step IAEA scale. A category '3' source by the IAEA standard 'is extremely unlikely, to cause injury to a person in the immediate vicinity'. The obvious conclusion of the analysis is that environmental management generated radioactive wastes have substantially less impact than radioactive sources if dispersed by terrorist-induced explosion or fire. From a health standpoint, the impact is very small. However, there is no basis to conclude that wastes are totally unattractive for use in a disruptive or economic damage event. Waste managers should be cognizant of this potential and take measures to ensure security of stored waste and waste shipments. (authors)

  10. Artificial skins: Hierarchical wrinkling

    Science.gov (United States)

    Huck, Wilhelm T. S.

    2005-04-01

    Wrinkling is a ubiquitous form of mechanical instability, occurring in such widely different systems as skin and lava flows. Hierarchical wrinkling leading to topographical features, with length scales spanning five orders of magnitude, has now been observed and harnessed in an artificial skin.

  11. Natural or Artificial Intelligence?.

    Czech Academy of Sciences Publication Activity Database

    Havlík, Vladimír

    Plze? : University of West Bohemia, 2013 - (Romportl, J.; Ircing, P.; Zackova, E.; Polak, M.; Schuster, R.), s. 15-27 ISBN 978-80-261-0275-5. [International Conference Beyond AI 2013. Plze? (CZ), 12.11.2013-14.11.2013] Institutional support: RVO:67985955 Keywords : artificial intelligence * natural intelligence * artifact * natural process * intrinsic intentionality Subject RIV: AA - Philosophy ; Religion

  12. Micromachined Artificial Haircell

    Science.gov (United States)

    Liu, Chang (Inventor); Engel, Jonathan (Inventor); Chen, Nannan (Inventor); Chen, Jack (Inventor)

    2010-01-01

    A micromachined artificial sensor comprises a support coupled to and movable with respect to a substrate. A polymer, high-aspect ratio cilia-like structure is disposed on and extends out-of-plane from the support. A strain detector is disposed with respect to the support to detect movement of the support.

  13. Artificial Gravity Research Plan

    Science.gov (United States)

    Gilbert, Charlene

    2014-01-01

    This document describes the forward working plan to identify what countermeasure resources are needed for a vehicle with an artificial gravity module (intermittent centrifugation) and what Countermeasure Resources are needed for a rotating transit vehicle (continuous centrifugation) to minimize the effects of microgravity to Mars Exploration crewmembers.

  14. Artificial recharge of groundwater

    Science.gov (United States)

    The Task Committee on Guidelines for Artificial Recharge of Groundwater, of the American Society of Civil Engineers' (ASCE) Irrigation and Drainage Division, sponsored an International Symposium on Artificial Recharge of Groundwater at the Inn-at-the-Park Hotel in Anaheim, Calif., August 23-27, 1988. Cosponsors were the U.S. Geological Survey, California Department of Water Resources, University of California Water Resources Center, Metropolitan Water District of Southern California, with cooperation from the U.S. Bureau of Reclamation, International Association of Hydrological Sciences, American Water Resources Association, U.S. Agency for International Development, World Bank, United Nations Department of Technical Cooperation for Development, and a number of local and state organizations.Because of the worldwide interest in artificial recharge and the need to develop efficient recharge facilities, the Anaheim symposium brought together an interdisciplinary group of engineers and scientists to provide a forum for many professional disciplines to exchange experiences and findings related to various types of artificial recharge; learn from both successful and unsuccessful case histories; promote technology transfer between the various disciplines; provide an education resource for communication with those who are not water scientists, such as planners, lawyers, regulators, and the public in general; and indicate directions by which cities or other entities can save funds by having reasonable technical guidelines for implementation of a recharge project.

  15. Artificial binary data scenarios

    OpenAIRE

    Dolnicar, Sara; Leisch, Friedrich; Weingessel, Andreas

    1998-01-01

    This manual describes artificial binary data scenarios. These data sets can be used to compare the performance of algorithms for market segmentation. The data sets described in this manual are available as packages for R (Splus) and as ASCII-files under htttp://www.ci.tuwien.ac.at/SFB/. (author's abstract)

  16. Artificial intelligence within AFSC

    Science.gov (United States)

    Gersh, Mark A.

    1990-01-01

    Information on artificial intelligence research in the Air Force Systems Command is given in viewgraph form. Specific research that is being conducted at the Rome Air Development Center, the Space Technology Center, the Human Resources Laboratory, the Armstrong Aerospace Medical Research Laboratory, the Armamant Laboratory, and the Wright Research and Development Center is noted.

  17. Artificial intelligence and automation

    CERN Document Server

    Bourbakis, NG

    1998-01-01

    Covering artificial intelligence and automation, these contributions discuss: the evolution of AI tools; an SPN knowledge representation scheme; software engineering using AI; the impact of AI in VLSI design automation; incremental adaptation as a method to improve reactive behaviour; and more.

  18. Environmental radioactivity in New Zealand and Rarotonga : annual report 1998

    International Nuclear Information System (INIS)

    During 1998, artificial radioactivity in the environment in New Zealand and Rarotonga continued to be at trace levels only, typical of recent years during which there has been no significant change in the radioactivity status of the environment. Atmospheric radioactivity was monitored at Kaitaia, Hokitika and Rarotonga, deposited radioactivity was monitored at Hokitika, and milk radioactivity was monitored in the Waikato, Taranaki and Westland. Average levels measured were: total beta activity in air, 0.1 mBq/m3. 90Sr deposition, 0.1 + or - 0.2 Bq/m2; 137Cs in milk, 0.1 Bq/g K; 90Sr in milk, 0.02 Bq/g Ca. Total beta activity deposition at Hokitika was 216 Bq/m2. Annual total 210Pb and 7Be depositions at Hokitika were 134 and 6410 Bq/m2 respectively. No artificial radionuclides, except 137Cs, were detected by gamma spectroscopic analysis of high-volume air filters during 1998, with weekly sampling periods. The annual-average atmospheric 137Cs concentration in the region, assessed by analysis of yearly air-filter aggregates, was 0.04 muBq/m3. Average atmospheric concentrations of natural 7Be and 210Pb were 3.7 mBq/m3 and 0.07 mBq/m3 respectively. (author). 9 refs., 5 tabs., 3 figs

  19. Environmental radioactivity in Turkey, 2007

    International Nuclear Information System (INIS)

    In this report, the activity concentrations of natural and artificial radionuclides, gross alpha/beta activities and air gamma dose rates in the environmental and food samples provided from Turkey's seven geographical regions within the environmental radioactivity monitoring program in 2007 are presented. The activity concentrations of the natural (238U, 232Th, 226Ra, 4:0K and 7Be) and artificial (137Cs, 134Cs, 90Sr, 238-239+240Pu, 241Am) radionuclides and gross alpha/beta activities in the samples were measured by using the gamma spectrometry, the alpha spectrometry, the liquid scintillation counter and the gross alpha /beta counting system. Results show that 137Cs and 90Sr radionuclides originating from the Chernobyl Nuclear Reactor accident in 1986 exist in some of samples even in low levels. The mean activity concentrations of 238U, 232Th, 226Ra and 40K in the studied surface soil samples were found as 32.1 Bq kg-1, 35.0 Bq kg-1, 29.0 Bq kg-1 and 446.7 Bq kg-1, respectively, while the mean activity concentrations of the fission product 137Cs was found as 18.4 Bq kg-1. While the activity concentrations of 238U, 232Th and 226Ra in the analyzed food samples are lower than the minimum detectable activity (MDA), 134Cs and 7Be radionuclides are not observed. The mean activity concentrations of 137Cs and 90Sr radionuclides are 0.24 Bq L-1 and 0.05 Bq L-1, respectively. (Includes 4 tables and 7 figures)

  20. Environmental radioactivity in Turkey, 2009

    International Nuclear Information System (INIS)

    In this report, the activity concentrations of natural and artificial radionuclides and gross alpha/beta activities measured in the environmental and food samples provided from Turkey's seven geographical regions within the environmental radioactivity monitoring program in 2009 and absorbed gamma dose rates in outdoor obtained by means of car-borne measurement system (Mobysis) are presented. The activity concentrations of the natural and artificial radionuclides and gross alpha/beta activities in the samples were measured by using the gamma spectrometry, the alpha spectrometry, the liquid scintillation counter and the gross alpha /beta counting system. The mean activity concentrations of 226Ra, 232Th and 40K in the analyzed surface samples were found as 34,7 ± 1,7 Bq kg-1, 35,4 ± 0,8 Bq kg-1 and 450,0 ± 17,9 Bq kg-1, respectively, while the mean activity concentration of the fission product 137Cs was found as 11,6 ± 0,5 Bq kg-1. The mean absorbed gamma dose rate in outdoor due to external exposure emitted by natural radionuclides in soil samples and the corresponding annual effective dose were evaluated as 54,6 nGy h-1 and 0,07 mSv y-1, respectively. The activity concentrations of 238U, 232Th and 226Ra in the analyzed food samples were lower than the minimum detectable activity (MDA) while 134Cs radionuclide was not observed. The mean activity concentrations of 137Cs and 90Sr radionuclides measured in the milk samples are 0,28 Bq L-1 and 0.05 Bq L-1, respectively. These values are lower than the limit value specified for foods subjected to control based on the regulation of the EU 737/90/EC. The total annual effective dose arising from the internal exposure from radiation emitting from 40K, l37Cs and 90Sr radionuclides analyzed in the food samples are evaluated as 193,0 ?Sv. In conclusion, the results of the monitoring programme in 2009 show that the levels of radioactivity in the environment are low and do not pose any significant risk to human health and the environment.

  1. Environmental radioactivity in Turkey, 2010

    International Nuclear Information System (INIS)

    In this report, the activity concentrations of natural and artificial radionuclides and gross alpha/beta activities measured in the environmental and food samples provided from 81 provinces of the country within the environmental radioactivity monitoring program in 2010 and outdoor gamma dose rates obtained by means of car-borne measurement system are presented. The activity concentrations of the natural and artificial radionuclides in the samples were measured by using the gamma spectrometry, the alpha spectrometry, the liquid scintillation counter and the gross alpha /beta counting system. The mean activity concentrations of 226Ra, 232Th and 40K in the analyzed surface samples were found as 28.11±1.23 Bq kg-1, 32.4±1.2 Bq kg-1 and 430.8±12.5, respectively, while the mean activity concentration of the fission product 137Cs was found as 9.78±0.79 Bq kg-1. The mean absorbed gamma dose rate in outdoor due to external exposure emitted by natural radionuclides in soil samples and the corresponding annual effective dose were evaluated as 50.5 nGy h-1 and 0.062 mSv y-1, respectively. Total indicative doses of the analyzed drinking water samples were below the limit values. The activity concentrations of 238U, 232Th and 226Ra in the analyzed food samples were lower than the minimum detectable activity while 134Cs radionuclide was not observed. The mean activity concentrations of 137Cs and 90Sr radionuclides measured in the milk samples are 1.01 Bq L-1 and 0.29 Bq L-1, respectively. These values are lower than the limit value specified for foods subjected to control based on the regulation of the EU 737/90/EC. The total annual effective dose arising from the internal exposure from radiation emitting from 40K, 137Cs and 90Sr radionuclides analyzed in the food samples are evaluated as 196.6 Sv. In conclusion, the results of the monitoring program in 2010 show that the levels of radioactivity in the environment are low and do not pose any significant risk to human health and the environment.

  2. Radioactivity in a mountain ecosystem: the Haut Bassin du Var

    International Nuclear Information System (INIS)

    After the Chernobyl accident, the IPSN realized a study of the radioactive fallout in the mountain area of the Var (France). Today the main radionuclides are the cesium 134 and 137, others disappeared because of their short half-life. In this paper, the artificial radioactivity of soils and sediments is concerned. The study shows a concentration of the contamination in some specific areas, especially in soils abounding in organic matter. The dose measured can not lead to significant exposures. (A.L.B.)

  3. Gross alpha radioactivity of drinking water in Venezuela

    International Nuclear Information System (INIS)

    Bottled mineral water is consumed by a large population in Venezuela. The alpha emitters concentration was measured in samples of bottled water and water springs collected near the surface. Approximately 30% of the total mineral water suppliers was monitored. a database on natural and artificial radioactivity in drinking water was produced. Results indicate that 54% of the waters sampled contain a total alpha radioactivity of less than 0.185 Bql-1 and only 12% above 0.37 Bql-1. Our results revealed a total annual dose of 2.3 mSv year-1. (author)

  4. AKTIS Nr. 12: To better understand radioactive aerosol deposit in order to better measure it; Radio-induced lesions: a new step towards healing; Modelling the collapse of an immersed grain column; To better model soot deposit; Towards the prediction of the leakage rate of containment enclosures

    International Nuclear Information System (INIS)

    This publication presents the main results of researches undertaken by the IRSN in the field of radiation protection, nuclear safety and security. The topics herein addressed are: radio-induced lesions as a new step towards healing (case of injection mesenchymal stem cells for the treatment of induced severe colorectal lesions), the modelling of the collapse of an immersed grain column (to study the nuclear fuel behaviour in an accidental situation through a modelling of fluid-grain interactions), a better understanding of radioactive aerosol deposit (to study particle or aerosol deposits after radioactive releases in the atmosphere in case of accident), a better modelling of soot deposits (in case of fire), the prediction of leakage rates of containment enclosures (ageing phenomena of installations, systems and equipment, with the case of cracks due to material ageing and resulting in confinement losses which could thus be quantified)

  5. Radioactive krypton gas separation

    International Nuclear Information System (INIS)

    Radioactive krypton is separated from a gas mixture comprising nitrogen and traces of carbon dioxide and radioactive krypton by selective adsorption and then cryogenic distillation of the prepurified gas against nitrogen liquid to produce krypton bottoms concentrate liquid, using the nitrogen gas from the distillation for two step purging of the adsorbent. 16 Claims, 8 Drawing Figures

  6. Radioactive waste management policy

    International Nuclear Information System (INIS)

    The speaker discusses the development of government policy regarding radioactive waste disposal in Canada, indicates overall policy objectives, and surveys the actual situation with respect to radioactive wastes in Canada. He also looks at the public perceptions of the waste management situation and how they relate to the views of governmental decision makers

  7. Sealed radioactive sources toolkit

    International Nuclear Information System (INIS)

    The IAEA has developed a Sealed Radioactive Sources Toolkit to provide information to key groups about the safety and security of sealed radioactive sources. The key groups addressed are officials in government agencies, medical users, industrial users and the scrap metal industry. The general public may also benefit from an understanding of the fundamentals of radiation safety

  8. Radioactive peptide hormones

    International Nuclear Information System (INIS)

    This chapter is concerned with the various methods that are employed to prepare radioactive peptide hormones. These include exchange techniques, controlled replacement of hydrogen by tritium, introduction of tritium atoms in pre-established positions. The last section deals with preparation and storage of radioactive polypeptides. 70 refs.; 3 figs.; 5 tabs

  9. K. Radioactive waste management

    International Nuclear Information System (INIS)

    Radioactive waste management is a controversial and emotive subject. This report discusses radioactivity hazards which arise from each stage of the fuel cycle and then relates these hazards to the New Zealand situation. There are three appendices, two of which are detailed considerations of a paper by Dr. B.L.Cohen

  10. Development of an experimental set-up for the measurement of neutron-induced fission and capture cross sections of highly radioactive fissile nuclei

    Directory of Open Access Journals (Sweden)

    Companis Iulia

    2014-04-01

    Full Text Available The measurement of neutron-capture cross sections of many actinides is complicated by the difficulty in separating capture ?-rays from the large fission-fragment prompt ?-ray background. For example, current estimates of the capture cross section of 233U show large discrepancies, with differences of more than 20%. To improve the accuracy of data, a new experimental set-up for the simultaneous measurement of the neutron-induced capture and fission cross sections was designed, assembled and optimized. The measurements will be performed at the GEel LINear Accelerator (GELINA neutron time-of-flight facility in Belgium, where neutron cross sections can be measured over a wide energy range with high energy resolution. The fission detector consists of a dedicated multi-plate high-efficiency ionization chamber (IC. The ?-rays produced in capture reaction are detected by an array of C6D6 scintillators. Fission ?–rays are distinguished from capture ?–rays by the anticoincidence signals from the IC and the C6D6 detectors. For the undetected fission events a correction has to be applied based on the efficiency of the IC that should be high and known with a high accuracy. The performance of the IC during dedicated test experiments is presented, focusing on the determination of the detection efficiency.

  11. Radioactivity and wildlife

    International Nuclear Information System (INIS)

    The official assumption is that if levels of radioactivity are safe for humans, they are safe for wildlife too. NCC sponsored a research project by the Institute of Terrestrial Ecology to find out what was known in this field. It appears that the assumption is justified to a certain extent in that mammals are identified as the organisms most vulnerable to the damaging effects of radioactivity. Other general principles are put forward: where there are radioactive discharges to the marine environment, coastal muds and saltmarshes can be particularly contaminated; upland habitats, with low nutrient status and subject to high rainfall, are likely to accumulate radioactivity from atmospheric discharges (e.g. Chernobyl, the wildlife effects of which are reported here). The document concludes that no deleterious effects of radioactivity on wild plants and animals have been detected in the UK, but acknowledges that there are still many gaps in our knowledge of the behaviour of radioisotopes in the natural environment. (UK)

  12. Radioactivity of household water in Finland

    International Nuclear Information System (INIS)

    A nationwide study on artificial and natural radioactivity in household water has been under way in Finland since the 1960s. The occurrence of artificial radionuclides in the surface water of drainage basins has been monitored extensively. The proportion of household water derived from surface waters in Finland is currently 48 %, but its usage is decreasing whereas that of groundwater is increasing at an annual rate of 1 - 2 %. The natural radioactivity of household water has been studied in almost all of the waters distributed by public waterworks and in 5400 private ground water wells. The downward trend in 90Sr, 137Cs and 3H concentrations in surface water continued from the middle 1960s until the Chernobyl accident. After the accident ten different radionuclides were detected in surface waters, but only 137Cs made a minor contribution the radiation dose. The maximum effective dose via ingestion of water was about 0.001 mSv in 1986, and considerably lower in the following years

  13. Radioecological observations in the trace-measurement and dosimetric evaluation of radioactive traces in the air; Radiooekologische Beobachtungen bei der Spurenmessung und dosimetrische Bewertung radioaktiver Spuren in der Luft

    Energy Technology Data Exchange (ETDEWEB)

    Walther, Clemens [Leibniz Univ. Hannover (Germany). Inst. fuer Radiooekologie und Strahlenschutz; Wershofen, Herbert [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany). Arbeitsgruppe Umweltradioaktivitaet

    2014-03-15

    The following topics are dealt with: Weekly measurement of {sup 137}Cs and {sup 40}K, long-time measurement series, natural radioactive nuclides, artificial radioactive nuclides, {sup 85}Kr, {sup 133}Xe, {sup 90}Sr, {sup 137}Cs, and {sup 238-240}Pu, the radioecology of {sup 129}I, dosimetric evaluation of radioactive traces in air. (HSI)

  14. Survey monitoring of environmental radioactivity in Gunsan area

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Byoung Ho; Ro, Jeong Suk [Kunsan Regional Radioactivity Monitoring Station, Gunsan (Korea, Republic of)

    2002-12-15

    At Regional Radioactivity Monitoring Station in Kunsan have been measured priodically in 2002 gross beta activities in the airborne dust, fallout, precipitation and tap water and gamma exposure rates. Artificial radionuclide of {sup 137}Cs in airborne dust, fallout and precipitation have also been monitored at the station. As a part of environmental radiation/radioactivity distribution survey around Jeon-buk, vegetables, fishes, shellfishes, drinking water (total 33ea) samples were taken from sampling sites which were selected by KINS. We analysis gamma isotope for all. No significant changes from the previous survey have been found in both beta activities and gamma exposure rates. As the results of analyzig an artificial nuclide concentration in living environmental sample in Jeon-buk are fee of radiological contaminants.

  15. Results 2005 of the surveillance of the artificial radioactivity levels of aquatic ecosystems in the basin of Seine-Normandy. Riviere 2005; Resultats 2005 de la surveillance des niveaux de la radioactivite artificielle d'ecosystemes aquatiques appartenant au bassin Seine-Normandie. Riviere 2005

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    Set up in 2004 by the A.C.R.O. the citizens network of radioecological surveillance, information and evaluation (R.I.V.I.E.R.E.) aims at making a follow-up of the radioactive contamination of the aquatic ecosystems on the scale of the Seine-Normandy pond: from Nogent-on-Seine to La Hague and from the Mont-Saint-Michel to the Treport. The peculiarity of this network, which also makes its strength is to associate strictly all those who wish to appropriate the knowledge of the radioactivity levels around to them. With R.I.V.I.E.R.E., the citizen is at the same moment an author and an actor of the surveillance of his environment as his information. An approach defended by the A.C.R.O. since about 20 years and which has no equivalent anywhere else. This project has four main objectives: to know the levels and the tendencies of the present radioactivity in the main aquatic ecosystems of the Seine-Normandy widened pond, and so feed a data base including more than 3000 analysis (limited to the gamma radioactivity and to the tritium); to allow the citizens who put a lot to appropriate the knowledge and the indispensable references to understand the radioactivity of their environment; to establish a support in the public information about the radioactivity in environment; to supply data to the national network of measures of the radioactivity in environment, network established by decree recently and in charge of the evaluation of the public exposure. (N.C.)

  16. Spatially Resolved Artificial Chemistry

    DEFF Research Database (Denmark)

    Fellermann, Harold

    2009-01-01

    Although spatial structures can play a crucial role in chemical systems and can drastically alter the outcome of reactions, the traditional framework of artificial chemistry is a well-stirred tank reactor with no spatial representation in mind. Advanced method development in physical chemistry has made a class of models accessible to the realms of artificial chemistry that represent reacting molecules in a coarse-grained fashion in continuous space. This chapter introduces the mathematical models of Brownian dynamics (BD) and dissipative particle dynamics (DPD) for molecular motion and reaction. It reviews calibration procedures, outlines the computational algorithms, and summarizes examplary applications. Four different platforms for BD and DPD simulations are presented that differ in their focus, features, and complexity.

  17. Ethical Artificial Intelligence

    OpenAIRE

    Hibbard, Bill

    2014-01-01

    This book-length article combines several peer reviewed papers and new material to analyze the issues of ethical artificial intelligence (AI). The behavior of future AI systems can be described by mathematical equations, which are adapted to analyze possible unintended AI behaviors and ways that AI designs can avoid them. This article makes the case for utility-maximizing agents and for avoiding infinite sets in agent definitions. It shows how to avoid agent self-delusion us...

  18. Artificial perception and consciousness

    Science.gov (United States)

    Caulfield, H. John; Johnson, John L.

    2000-06-01

    Perception has both unconscious and conscious aspects. In all cases, however, what we perceive is a model of reality. By brain construction through evolution, we divide the world into two parts--our body and the outside world. But the process is the same in both cases. We perceive a construct usually governed by sensed data but always involving memory, goals, fears, expectations, etc. As a first step toward Artificial Perception in man-made systems, we examine perception in general here.

  19. Artificial organisms that sleep.

    OpenAIRE

    Mirolli, Marco; Parisi, Domenico

    2003-01-01

    Abstract Populations of artificial organisms live in an environment in which light is cyclically present (day) or absent (night). Since being active during night is non-adaptive (activity consumes energy which is not compensated by the food found at night) the organisms evolve a sleep/wake behavioral pattern of being active during daytime and sleeping during nighttime. When the population moves to a different environment that contains "caves", they have to get out of a cave although the dark ...

  20. Artificial sweeteners – a review

    OpenAIRE

    Chattopadhyay, Sanchari; Raychaudhuri, Utpal; Chakraborty, Runu

    2011-01-01

    Now a days sugar free food are very much popular because of their less calorie content. So food industry uses various artificial sweeteners which are low in calorie content instead of high calorie sugar. U.S. Food and Drug Administration has approved aspartame, acesulfame-k, neotame, cyclamate and alitame for use as per acceptable daily intake (ADI) value. But till date, breakdown products of these sweeteners have controversial health and metabolic effects. On the other hand, rare sugars are ...

  1. Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Kapil Nahar

    2012-12-01

    Full Text Available An artificial neural network is an information-processing paradigm that is inspired by the way biological nervous systems, such as the brain, process information.The key element of this paradigm is the novel structure of the information processing system. It is composed of a large number of highly interconnected processing elements (neurons working in unison to solve specific problems.Ann’s, like people, learn by example.

  2. Essentials of artificial intelligence

    CERN Document Server

    Ginsberg, Matt

    1993-01-01

    Since its publication, Essentials of Artificial Intelligence has beenadopted at numerous universities and colleges offering introductory AIcourses at the graduate and undergraduate levels. Based on the author'scourse at Stanford University, the book is an integrated, cohesiveintroduction to the field. The author has a fresh, entertaining writingstyle that combines clear presentations with humor and AI anecdotes. At thesame time, as an active AI researcher, he presents the materialauthoritatively and with insight that reflects a contemporary, first hand

  3. Management of radioactive wastes

    International Nuclear Information System (INIS)

    The disposal of radioactive wastes is perhaps the most controversial and least understood aspect of the use of nuclear materials in generating electrical power, the investigation of biochemical processes through tracer kinetics, and the diagnosis and treatment of disease. In the siting of nuclear power facilities, the disposal of radioactive wastes is invariably posed as the ultimate unanswerable question. In the fall of 1979, biochemical and physiologic research employing radioactive tracers was threatened with a slowdown resulting from temporary closure of sites for disposal of low-level radioactive wastes (LLW). Radioactive pharmaceuticals used extensively for diagnosis and treatment of human disease have increased dramatically in price, partly as a result of the escalating cost of disposing of radioactive wastes created during production of the labeled pharmaceuticals. These problems have resulted in identification of the disposal of LLW as the most pressing issue in the entire scheme of management of hazardous wastes. How this issue as well as the separate issue of disposal of high-level radioactive wastes (HLW) are being addressed at both national and state levels is the subject of this chapter

  4. Measurement of radioactivity

    International Nuclear Information System (INIS)

    The measurement of environmental radioactivity in Japan started from the time of the nuclear test at Bikini in 1954, and Science and Technology Agency has established ''Measuring Procedure of Radioactivity'' in 1957. This is total beta radiation measurement, and now the revised draught including nine points to be revised has been made. Since then, analyzing procedures were established for radioactive strontium, cesium-137, radioactive iodine, and radioactive cobalt, with NaI(Tl) scintillation spectrometers, for radioactive zirconium and instrumental analysis using Ge(Li) semiconductor detectors. Presently the tritium-analyzing procedure is under discussion. As the manuals for individual analyses have been instituted, the ''general manual'' for applying those has become to be required. The problems lie not in individual procedures but in the purpose of radioactivity measurement, monitoring method, and the evaluation of data obtained. The compilation of the manual started in 1973, but now temporarily stopped because of a new problem which is the opinion insisting that manual is to include the procedures for the estimation of population exposure dose based on the data obtained. (Wakatsuki, Y.)

  5. Radioactivity in drinking water. From basics to practice

    International Nuclear Information System (INIS)

    Radioactive material of natural and artificial origin contributes to the radiation exposure of the public. In this paper the current scientific and legal basics are given to show comprehensively the evaluation methods and limitation of public radiation exposure. The implementation of concepts and methods into the radiation protection practice with consideration of the experience in Austria is demonstrated. International developments give an outlook on future solutions of this specific environmental related radiation protection problem. (orig.)

  6. Artificial sweetener; Jinko kanmiryo

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1999-08-01

    The patents related to the artificial sweetener that it is introduced to the public in 3 years from 1996 until 1998 are 115 cases. The sugar quality which makes an oligosaccharide and sugar alcohol the subject is greatly over 28 cases of the non-sugar quality in the one by the kind as a general tendency of these patents at 73 cases in such cases as the Aspartame. The method of manufacture patent, which included new material around other peptides, the oligosaccharide and sugar alcohol isn`t inferior to 56 cases of the formation thing patent at 43 cases, and pays attention to the thing, which is many by the method of manufacture, formation. There is most improvement of the quality of sweetness with 31 cases in badness of the aftertaste which is characteristic of the artificial sweetener and so on, and much stability including the improvement in the flavor of food by the artificial sweetener, a long time and dissolution, fluid nature and productivity and improvement of the economy such as a cost are seen with effect on a purpose. (NEDO)

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

    International Nuclear Information System (INIS)

    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 238U series (226Ra, 214Pb and 214Bi), 232Th series (228Ac), 40K and fission product 137Cs 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. (authors)

  8. A scenario for a genetically controlled fission of artificial vesicles.

    DEFF Research Database (Denmark)

    Bönzli, Eva; Hadorn, Maik

    Artificial vesicles have been used for decades as model systems of biological cells to investigate scientific questions in simulacra. In recent years, the significance of artificial vesicles further increased because they represent ideal candidates to become the building block of a de novo construction of a cell in a bottom-up manner. Numerous efforts to build an artificial cell that bridge the living and non-living world will most presumably represent one of the main goals of science in the 21st century. It was shown that artificial genetic programs and the required cellular machinery can be incorporated into vesicles, and therefore allow the synthesis of a large number of proteins (Noireaux et al. 2005). However, vesicle fission remains one of the upcoming challenges in the artificial cell project (Noireaux et al. 2011). So far, vesicle fission is implemented by applying mechanical stress to vesicles (Hanczyc et al. 2003). In the present work, we developed a scenario how a genetically controlled fission of vesicles may be achieved by the synthesis of a special class of viral proteins within artificial vesicles. Because the authors already have a lot of experience in the water-in-oil emulsion transfer method to prepare vesicles, the base for the development of a protocol to induce fission in artificial cell may be available.

  9. Radioactive waste disposal

    International Nuclear Information System (INIS)

    The current disposal concept for radioactive waste in the FRG was discussed in the framework of this seminar. In addition to this concept for the treatment of radioactive waste also the volume of this waste is indicated. The present state of the two repositories 'Konrad' and 'Gorleben' is explained, as well as the requirements on waste packages for transportation, intermediate and ultimate storage. The final part discusses the conditioning of this radioactive waste and the control of the barrels as regards the observance of the requirements. (orig.)

  10. Predisposal Radioactive Waste Management

    International Nuclear Information System (INIS)

    Recognition of the importance of the safe management of radioactive waste means that, over the years, many well-established and effective techniques have been developed, and the nuclear industry and governments have gained considerable experience in this field. Minimization of waste is a fundamental principle underpinning the design and operation of all nuclear operations, together with waste reuse and recycling. For the remaining radioactive waste that will be produced, it is essential that there is a well defined plan (called a waste treatment path) to ensure the safe management and ultimately the safe disposal of radioactive waste so as to guarantee the sustainable long term deployment of nuclear technologies

  11. Radioactivity and environment

    International Nuclear Information System (INIS)

    The year 1996 is going to be the anniversary year for the nuclear energy. the centenary of the radioactivity discovery by the physician Henri Becquerel, anniversary of forty years of the putting into operation of the first french nuclear power plant (G1 at Marcoule), anniversary of thirty years of french nuclear tests in Polynesia, without forgetting the ten candles for the Chernobyl disaster. Here is an inquiry to answer to some questions such what is radioactivity, where does it come from, what is dangerous, what is not dangerous. The first article tells us the history of radioactivity discovery until the super Phenix reactor. (N.C.)

  12. Radioactivity; La radioactivite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This pedagogical document presents the origin, effects and uses of radioactivity: where does radioactivity comes from, effects on the body, measurement, protection against radiations, uses in the medical field, in the electric power industry, in the food (ionization, radio-mutagenesis, irradiations) and other industries (radiography, gauges, detectors, irradiations, tracers), and in research activities (dating, preservation of cultural objects). The document ends with some examples of irradiation levels (examples of natural radioactivity, distribution of the various sources of exposure in France). (J.S.)

  13. Natural occurring radioactive substances. Vol. 1

    International Nuclear Information System (INIS)

    Naturally occurring radioactive substances produced by cosmic rays of those of terrestrial origin are surveyed. The different radioactive decay series are discussed. Special emphasis is given to the element radium as regards its properties and distribution in different environmental samples. The properties of naturally occurring k-40 and its distribution in different natural media are also outlined. Induced radionuclides which are formed as a result of the interaction of cosmic rays with the constituents of the atmosphere are mentioned. In this respect the intensity of natural background radiation and the dose at different locations and levels is surveyed. Some regions of exceptionally high radioactivity which result in high exposure rates are mentioned. Monazite deposits and water springs are mentioned in some detail. The Oklo phenomenon as a natural reactor is also discussed. 8 tabs

  14. Artificial Gravity: Effects on Bone Turnover

    Science.gov (United States)

    Heer, M.; Zwart, S /R.; Baecker, N.; Smith, S. M.

    2007-01-01

    The impact of microgravity on the human body is a significant concern for space travelers. Since mechanical loading is a main reason for bone loss, artificial gravity might be an effective countermeasure to the effects of microgravity. In a 21-day 6 head-down tilt bed rest (HDBR) pilot study carried out by NASA, USA, the utility of artificial gravity (AG) as a countermeasure to immobilization-induced bone loss was tested. Blood and urine were collected before, during, and after bed rest for bone marker determinations. Bone mineral density was determined by DXA and pQCT before and after bed rest. Urinary excretion of bone resorption markers (n-telopeptide and helical peptide) were increased from pre-bed rest, but there was no difference between the control and the AG group. The same was true for serum c-telopeptide measurements. Bone formation markers were affected by bed rest and artificial gravity. While bone-specific alkaline phosphatase tended to be lower in the AG group during bed rest (p = 0.08), PINP, another bone formation marker, was significantly lower in AG subjects than CN before and during bed rest. PINP was lower during bed rest in both groups. For comparison, artificial gravity combined with ergometric exercise was tested in a 14-day HDBR study carried out in Japan (Iwase et al. J Grav Physiol 2004). In that study, an exercise regime combined with AG was able to significantly mitigate the bed rest-induced increase in the bone resorption marker deoxypyridinoline. While further study is required to more clearly differentiate bone and muscle effects, these initial data demonstrate the potential effectiveness of short-radius, intermittent AG as a countermeasure to the bone deconditioning that occurs during bed rest and spaceflight. Future studies will need to optimize not only the AG prescription (intensity and duration), but will likely need to include the use of exercise or other combined treatments.

  15. Nuclear power stations: environmental surveillance of radioactivity

    International Nuclear Information System (INIS)

    Because of the radiations they emit, radioactive substances can be detected, identified and measured at extremely low concentrations ? the corresponding masses are lower by a factor ranging from 1000 to 10 000 than those that can be measured by any other chemical or physical method, however precise, applied to non-radioactive substances. Radioisotopes can therefore be detected in the environment at levels much lower than those at which genuine public health problems begin to arise. Unfortunately, we cannot say the same of numerous non-radio active pollutants, which can be measured only at concentrations very close to, or even exceeding, the toxicity threshold. In the mind of the uninformed public confusion seems quite frequently to reign as between the detection threshold and the toxicity threshold. This undoubtedly explains the following situation which is, to say the least, paradoxical: people are afraid of the hypothetical effects of radioactivity at ridiculously low levels, whereas nobody is alarmed at the fact that the toxicity limits for a very large number of non-radioactive, but very real pollutants are being exceeded almost continuously. The sum of all artificial irradiations does not exceed the normal fluctuations of natural irradiation, and if the genetic effects of very low radiation doses were truly cumulative, the natural radiation to which we are all exposed and which is by far the highest would by itself have eliminated every trace of life on earth long ago. Lastly, let us not forget that merely the use of X-rays in medicine, particularly in radiodiagnosis, represents an additional average artificial irradiation of the population amounting to double the natural radiation (100 millirem per year). This is about 100 times the irradiation which would accrue from nuclear industry even according to the most pessimistic estimate. We have seen that the measures described above will make it genuinely possible to maintain environmental radioactivity in all circumstances at a level which is perfectly compatible with public health regulations. Far from constituting a hazard to the public, nuclear facilities can, by virtue of the strictness of the controls to which they are subjected, serve as a model for combating numerous unacceptable conventional pollutants of the environment, the most alarming of which, indeed, nuclear power will undoubtedly cause to disappear in the long run

  16. Environmental radioactivity surveillance programme 1999 and 2000

    International Nuclear Information System (INIS)

    The Radiological Protection Institute of Ireland continued to monitor levels of radioactivity in air, drinking water and foodstuffs in 1999 and 2000 and the results are presented in this report, the sixth in a series dealing with the terrestrial environment. Radioactivity is present in the terrestrial environment due to natural processes, the testing of nuclear weapons in the atmosphere, accidents such as the Chernobyl accident and the routine discharge of radionuclides from nuclear installations. The Institute monitored airborne radioactivity at ten stations throughout the country. One site was equipped to detect the presence of krypton-85, a radionuclide which is released into the environment primarily as a result of the reprocessing of nuclear fuel at installations such as Sellafield in the UK and La Hague in France. Both in 1999 and 2000, levels of radionuclides in airborne particulates were low and consistent with measurements in previous years. Public water supplies are sampled from each county at least every four years with supplies to certain major population centres sampled annually. Water supplies from eleven counties were sampled between 1999 and 2000 and all of the waters tested were found to be within legal requirements for water quality from a radiological point of view. The levels of artificial radioactivity in milk and other foodstuffs such as milk products, baby foods, beef, lamb, poultry and vegetables continued to be very low in 1999 and 2000 and, for the majority of samples, below the detection limits. External gamma dose rates were monitored continuously at twelve locations around the country. The dose rate was recorded every twenty minutes and the readings transmitted automatically to the Institute's computer database at Clonskeagh (Dublin). No abnormally high levels were observed at any of the twelve stations in either 1999 or 2000. The data presented in this report demonstrate that the levels of artificial radioactivity in the Irish terrestrial environment, including foodstuffs, remain extremely low and do not pose a significant risk to health. Nonetheless, the Radiological Protection Institute of Ireland remains vigilant and will continue to monitor the exposure of people living in Ireland to all relevant sources of ionising radiation

  17. Research on radioactive sources safety assessment based on BP neural network

    International Nuclear Information System (INIS)

    Based on artificial neural network and BP network principle, a mathematical model of radioactive sources safety assessment system is built. To train the model using MATLAB simulation software and improve the factor weight influencing radioactive sources safety assessment gradually can obtain the minimal value of mean-square error between the actual output and the expected output of the network sample. It is proved by simulation calculation that BP network method has the better precision. (authors)

  18. Surveillance of radioactivity in the atmosphere between prognosis and measurement - early alert in the Deutscher Wetterdienst

    International Nuclear Information System (INIS)

    The Deutscher Wetterdienst (DWD) 'German Meteorological Service' is legally responsible for the large-scale surveillance of radioactivity in the atmosphere. For an early alert of artificial radioactivity gamma-ray-spectrometry of aerosols is performed at selected meteorological stations of the synoptic-climatological network. Results of measurements as well as dispersion calculations are urgently required for making further decisions. The combination of measurements and forecasts combined with airborne measurements in an alert-situation is discussed. (orig.)

  19. Environmental radioactivity at the Peruvian Scientific Station Machu Picchu 1999 - 2000 Antarctic region

    International Nuclear Information System (INIS)

    The Peruvian Institute of Nuclear Energy (IPEN) initiated the Environmental Radioactivity studies in the Antarctic Region in 1996. The objective of this research was to determine the levels of natural and artificial radioactivity achieving the evaluation of the radiological status in the antarctic region. Samples of brown algae (phaeophyta), lichens, moss, gramineous, soil, marine sediment, sea water and air were collected in the surrounding area of the Machu Picchu Scientific Station. This study shows the results corresponding to the 1999-2000 period

  20. Tissue culture of osteogenic sarcoma in rats, induced by radioactive phosphorus P-32 and the effect of the anti-cancerous agents on these tumor cells under tissue culture

    International Nuclear Information System (INIS)

    Small pieces of osteogenic sarcoma, induced into albino rats of the C.F. Wistar strain by injection of radioactive phosphorus 32P, were cultured in mixtures of Eagle's minimum essential medium and 20% calf serum. The tumor cells cultured in this way were transplanted into the subcutaneous tissue or the intraabdominal cavity to healthy albino rats. The effect of the anticancerous agents was evaluated by the decrease of nucleic acid composition in these cultured tumor cells. As anti-cancerous agents, cyclophosphamide (CPA), mitomycin C(MMC), and 5-fluorouracil(5-FU) were put into contact with the tumor cells in cultures for two hours under the following dilutions: CPA; 10-6, 10-5, 10-4 g/ml. MMC; 2 x 10-8, 2 x 10-7, 2 x 10-6 g/ml. 5-FU; 2 x 10-6, 2 x 10-5, 2 x 10-4 g/ml. The results are as follows: Three of the seven osteogenic sarcomas in rats were successfully cultured, one of them through more than eighteen generations. After about five hundred thousand cultured cells had been transplanted into the subcutaneous tissues or abdominal cavities of rats, tumors grew in all of them. The histological findings of the tumors in the second generation were quite similar to those of the original tumor. The same process was repeated three times and the tumor showed histogical findings similar to those of the original ones. The capability of nucleic acid synthesis in these cells was decreased at twenty fours after CPA contact and at forty eight hours after MMC. (J.P.N.)

  1. Literature in focus: The history of radioactivity

    CERN Multimedia

    2006-01-01

    René Bimbot, an expert in nuclear physics, will be coming to present his book - The History of Radioactivity. The work provides a summary of our accumulated knowledge of radioactivity and its applications, from its discovery to the present day. Presented in layman's terms, and backed by plenty of illustrations, the work creates the link between the rudimentary knowledge available in the times of Becquerel and the Curies and contemporary physics. It takes us on a great physics adventure, from the nucleus to the quark, from artificial radioactivity to radiotherapy, from the discovery of fission to nuclear reactors, not forgetting dating methods. Finally, the work provides a wealth of practical information on radiation and on matters relating to nuclear waste. A former Research Director at the CNRS, a heavy-ion physicist at the Orsay Nuclear Physics Institute, René Bimbot is no stranger to CERN. At the beginning of the 1980s, he worked on the CERN Synchrocyclotron, before joining the GANIL experiment in 1985...

  2. Environmental radioactivity at Machu Picchu Scientific Station

    International Nuclear Information System (INIS)

    Studies on environmental radioactivity at the Peruvian Scientific Station were carried out in the last two austral summer periods. The main objective of this study is to establish an environmental radiological monitoring program for evaluating environmental components and achieving a baseline study related to artificial and natural radioactivity levels. For this purpose, samples such as seaweeds, mosses, lichens, soil seawater, ice, marine sediment and underground water were collected from the area surrounding the station starting from Punta Crepin to Playa Inca and Playa Naylamp; then they were pre-conditioned in Machu Picchu Station and were sent to the Environmental Radioactivity laboratory of 'Racso' Peruvian Nuclear Center to conduct beta and gamma spectrometry. The Obtained results showed the presence of Cs-137 in geological components (soil and sediment) and in biological components (lichens and mosses). Nevertheless, those levels seem to be in a range of normal fluctuations after atmospheric nuclear testing and they are not considered to be dangerous to the ecosystem of the Antarctic Region. On the other hand, high concentration of Be-7 has been detected in seaweed and lichens. Other natural radionuclide detected were Ra-226, Bi-214 and K-40

  3. Environmental radioactivity monitoring for radiation protection

    International Nuclear Information System (INIS)

    The present research was conducted in the frame of a program of routine radioactivity surveillance around the Thai Research Reactor (TRR-1) as well as for the investigation of contamination due to nuclear weapons tests. Samples of air, water, fallout, soil, grass, vegetables, seafood, fish, and meat were collected from five stations throughout the country and measured for gross alpha, beta, and gamma radioactivity and for Cs-137 and K-40 concentration. The methods used were the standard oneswell established in routine laboratory practice. Cumulative annual radiation dose from natural gamma radiation exposure of the population was also measured by TLD LiF dosemeters. Indoor and outdoor exposures were also compared. Results indicate that the gross radioactivity and the concentration of Cs-137 and K-40 in environmental samples do not exceed values considered normal. The average cumulative annual radiation dose from natural gamma radiation during the period 1978-1980 was 80.4+-27 mrem. Comparison between in- and outdoor doses showed that the latter are higher in the two (out of five) locations where the data were available. No indication is given on the type of building material used in the areas under examination, whether wood or any other traditional material of natural or artificial origin

  4. Understanding radioactive waste

    Energy Technology Data Exchange (ETDEWEB)

    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)

  5. Radioactive pollution, ch. 6

    International Nuclear Information System (INIS)

    Disposal of radioactive wastes from nuclear power plants into surface waters as well as the atmosphere is discussed. Man-rem data are compared and expected quantities for disposal by power plants in the Netherlands are tabulated

  6. Understanding radioactive waste

    International Nuclear Information System (INIS)

    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)

  7. Uranium Deposits Radioactive Hazards

    International Science & Technology Center (ISTC)

    Assessment of Radioactive Hazard of Developed Jilskiy (Kyrgyzstan), Adrasman and Taboshar (Tajikistan) Uranium Deposits, Development and Typification of Actions on Rehabilitation of the Areas and Facilities for the Central Asia Region

  8. Law of radioactive minerals

    International Nuclear Information System (INIS)

    Legal device done in order to standardize and promote the exploration and explotation of radioactive minerals by peruvian and foreign investors. This device include the whole process, since the prospection until the development, after previous auction given by IPEN

  9. Radioactivity in mineral waters

    International Nuclear Information System (INIS)

    In France, there are more than 1 400 thermal springs. Among them we have, until now, analysed the radioactivity of 750. Radioactivity in 26 of them, including the best-known mineral waters in France, has been the object of a thorough survey regarding the amount of or activity in Radium (226Ra), Uranium (238U, 234U), Thorium (232Th, 230Th, 228Th), Potassium (40K), and for some of them, Radon (222Rn). A particular attention has been brought to the radioactive equilibrium and disequilibrium in these waters, and more especially to the disequilibrium by excess of concentration of 234U which we have stated in 6 French thermal springs. The results of this study show that radioactivity in French mineral waters is very low, sometimes non measurable with usual technical means, and that the health hazards linked with the consumption of these waters are negligible. 2 figs., 7 tabs., 16 refs

  10. Radioactive sources service

    CERN Multimedia

    2006-01-01

    Dear Users, A new web interface is now available for requesting radioactive sources: http://cern.ch/rp-sources/request This link is also available from the radioactive sources service main page: http://cern.ch/rp-sources From now on, please submit your request via the above interface, which has been developed in order to improve the service. Thank you in advance for your collaboration!

  11. Radioactive Substances Act 1960

    International Nuclear Information System (INIS)

    This Act regulates the keeping and use of radioactive material and makes provision for the disposal and storage of radioactive waste in the United Kingdom. It provides for a licensing system for such activities and for exemptions therefrom, in particular as concerns the United Kingdom Atomic Energy Authority. The Act repeals Section 4(5) of the Atomic Energy Authority Act, 1954 which made temporary provision for discharge of waste on or from premises occupied by the Authority. (NEA)

  12. Radioactive waste disposal policy

    International Nuclear Information System (INIS)

    The responsibilities of the Minister of Agriculture, Fisheries and Food and Ministry policy on radioactive waste disposal are described. The disposal of solid radioactive waste at sea is subject to detailed safeguards developed within two international agreements to which the United Kingdom is a contracting party. The agreements are discussed together with a research and monitoring programme to provide scientific data for informed decisions on waste disposal authorisations and dumping licences. (U.K.)

  13. Transport of radioactive materials

    International Nuclear Information System (INIS)

    The purpose of this Norm is to establish, relating to the TRANSPORT OF RADIOACTIVE MATERIALS, safety and radiological protection requirements to ensure an adequate control level of the eventual exposure of persons, properties and environment to the ionizing radiation comprising: specifications on radioactive materials for transport; package type selection; specification of the package design and acceptance test requirements; arrangements relating to the transport itself; administrative requirements and responsibilities. (author)

  14. New theories of ?-radioactivity

    Scientific Electronic Library Online (English)

    P.O.G., Ogunbade; S.A., Rakityansky.

    2007-04-01

    Full Text Available We review the radioactive decay of nuclei via emission of ?-particles using three different theoretical approaches. The half-lives of the radioactive nuclei, calculated using these three methods, are compared with each other and with available experimental data. The results show that the superasymme [...] tric fission model with the double-folding procedure for obtaining the ?-nucleus potential is the most reliable among the three models studied.

  15. Radioactive materials transport

    International Nuclear Information System (INIS)

    The development of peaceful applications of nuclear energy results in the increase of transport operations of radioactive materials. Therefore strong regulations on transport of radioactive materials turns out to be a necessity in Tunisia. This report presents the different axes of regulations which include the means of transport involved, the radiation protection of the carriers, the technical criteria of security in transport, the emergency measures in case of accidents and penalties in case of infringement. (TEC). 12 refs., 1 fig

  16. Dynamic radioactive particle source

    Energy Technology Data Exchange (ETDEWEB)

    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.

  17. 40 Years Of Environmental Radioactivity Monitoring

    International Nuclear Information System (INIS)

    This book introduces 40 years of environmental radioactivity monitoring, which concludes summary, yesterday and today of radioactivity monitoring, development direction of radioactivity monitoring home and foreign, monitoring system on environmental radioactivity, monitoring system and running of environmental radioactivity, quality management of analysis of environmental radioactivity, international cooperation, research and development of technology, monitoring report of nationwide environmental radioactivity, monitoring of ocean environmental radioactivity, monitoring activity on major environmental radioactivity and development direction of measurement monitoring on environmental radioactivity.

  18. Survey monitoring of environmental radioactivity in Daegu area

    International Nuclear Information System (INIS)

    The objectives of the project are to monitor an abnormal radiation level in Taegu and Kyungpook region, and to enhance our ability to prepare for the radiological emergency situation by establishing the radioactivity monitoring system in Taegu and Kyungpook region. In this report, we summarized a gamma exposure rates, a gross beta and gamma radionuclide activities for the environmental samples of airborned-dust. precipitation, fallout and tap water collected in Taegu radioactivity monitoring center, and a gamma radionuclide activities for the 28 grocery samples, such as tea, nut and mushroom, rice, chinese cabbage, wormwood and pine needles, soil and drinking water which were obtained from Taegu and Kyungpook region to establish the basic data base for estimating the internal exposure. In conclusion, it didn't appear any evidence for newly pollution of artificial radioactivity in Taegu and Kyungpook region

  19. Survey monitoring of environmental radioactivity in Daegu area

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Hee Dong; Lee, Hae Young; Yang, Chan Sun [Kyungpook National Univ., Daegu (Korea, Republic of)

    2001-12-15

    The objectives of the project are to monitor an abnormal radiation level in Taegu and Kyungpook region, and to enhance our ability to prepare for the radiological emergency situation by establishing the radioactivity monitoring system in Taegu and Kyungpook region. In this report, we summarized a gamma exposure rates, a gross beta and gamma radionuclide activities for the environmental samples of airborned-dust. precipitation, fallout and tap water collected in Taegu radioactivity monitoring center, and a gamma radionuclide activities for the 28 grocery samples, such as tea, nut and mushroom, rice, chinese cabbage, wormwood and pine needles, soil and drinking water which were obtained from Taegu and Kyungpook region to establish the basic data base for estimating the internal exposure. In conclusion, it didn't appear any evidence for newly pollution of artificial radioactivity in Taegu and Kyungpook region.

  20. Parallel artificial liquid membrane extraction

    DEFF Research Database (Denmark)

    Gjelstad, Astrid; Rasmussen, Knut Einar; Parmer, Marthe Petrine; Pedersen-Bjergaard, Stig

    2013-01-01

    This paper reports development of a new approach towards analytical liquid-liquid-liquid membrane extraction termed parallel artificial liquid membrane extraction. A donor plate and acceptor plate create a sandwich, in which each sample (human plasma) and acceptor solution is separated by an artificial liquid membrane. Parallel artificial liquid membrane extraction is a modification of hollow-fiber liquid-phase microextraction, where the hollow fibers are replaced by flat membranes in a 96-well ...

  1. Artificial Life Simulation in Bioinformatics

    OpenAIRE

    M.A. Mabayoje; MUFTAU O. W; ABIKOYE O.C

    2011-01-01

    Computer simulation of life is often used to study essential properties of living systems (such as evolution and adaptive behaviour).Artificial life is generated with the help of substituting blood corpuscles (blood cells). However, no truly safe and effective artificial blood product is available. Meanwhile, [2][7] has been a motivation for creating complex systems that are similar to biological system. The aim of this work is to simulate and implement artificial life through the use of comp...

  2. Progress in artificial chromosome technology.

    OpenAIRE

    Monaco, ZL; Moralli, D

    2006-01-01

    Artificial chromosomes is an exciting technology which has developed rapidly since the late 1990s. HACs (human artificial chromosomes) are autonomous molecules that can function and segregate as normal chromosomes in human cells. The advantages of an artificial-chromosome-based system are 2-fold. First, HACs are an excellent research tool for investigating the requirements for normal chromosome structure and function during the cell cycle. They are important in defining the sequence requireme...

  3. Polymer artificial muscles

    Directory of Open Access Journals (Sweden)

    Tissaphern Mirfakhrai

    2007-04-01

    Full Text Available The various types of natural muscle are incredible material systems that enable the production of large deformations by repetitive molecular motions. Polymer artificial muscle technologies are being developed that produce similar strains and higher stresses using electrostatic forces, electrostriction, ion insertion, and molecular conformational changes. Materials used include elastomers, conducting polymers, ionically conducting polymers, and carbon nanotubes. The mechanisms, performance, and remaining challenges associated with these technologies are described. Initial applications are being developed, but further work by the materials community should help make these technologies applicable in a wide range of devices where muscle-like motion is desirable.

  4. Bayesian artificial intelligence

    CERN Document Server

    Korb, Kevin B

    2010-01-01

    Updated and expanded, Bayesian Artificial Intelligence, Second Edition provides a practical and accessible introduction to the main concepts, foundation, and applications of Bayesian networks. It focuses on both the causal discovery of networks and Bayesian inference procedures. Adopting a causal interpretation of Bayesian networks, the authors discuss the use of Bayesian networks for causal modeling. They also draw on their own applied research to illustrate various applications of the technology.New to the Second EditionNew chapter on Bayesian network classifiersNew section on object-oriente

  5. Is Intelligence Artificial?

    OpenAIRE

    Greer, Kieran

    2014-01-01

    Our understanding of intelligence is directed primarily at the level of human beings. This paper attempts to give a more unifying definition that can be applied to the natural world in general. The definition would be used more to verify a degree of intelligence, not to quantify it and might help when making judgements on the matter. A version of an accepted test for AI is then put forward as the 'acid test' for Artificial Intelligence itself. It might be what a free-thinkin...

  6. Uncertainty in artificial intelligence

    CERN Document Server

    Kanal, LN

    1986-01-01

    How to deal with uncertainty is a subject of much controversy in Artificial Intelligence. This volume brings together a wide range of perspectives on uncertainty, many of the contributors being the principal proponents in the controversy.Some of the notable issues which emerge from these papers revolve around an interval-based calculus of uncertainty, the Dempster-Shafer Theory, and probability as the best numeric model for uncertainty. There remain strong dissenting opinions not only about probability but even about the utility of any numeric method in this context.

  7. Marcos da história da radioatividade e tendências atuais / Landmarks in the history of radioactivity and current tendencies

    Scientific Electronic Library Online (English)

    Allan Moreira, Xavier; André Gomes de, Lima; Camila Rosa Moraes, Vigna; Fabíola Manhas, Verbi; Gisele Gonçalves, Bortoleto; Karen, Goraieb; Carol Hollingworth, Collins; Maria Izabel Maretti Silveira, Bueno.

    2007-02-01

    Full Text Available [...] Abstract in english The first days of radioactivity, the discoveries of X-rays, radioactivity, of alpha- and beta- particles and gamma- radiation, of new radioactive elements, of artificial radioactivity, the neutron and positron and nuclear fission are reviewed as well as several adverse historical marks, such as the [...] Manhattan project and some nuclear and radiological accidents. Nuclear energy generation in Brazil and the world, as an alternative to minimize environmental problems, is discussed, as are the medicinal, industrial and food applications of ionizing radiation. The text leads the reader to reflect on the subject and to consider its various aspects with scientific and technological maturity.

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

    International Nuclear Information System (INIS)

    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.)

  9. Marcos da história da radioatividade e tendências atuais Landmarks in the history of radioactivity and current tendencies

    Directory of Open Access Journals (Sweden)

    Allan Moreira Xavier

    2007-02-01

    Full Text Available The first days of radioactivity, the discoveries of X-rays, radioactivity, of alpha- and beta- particles and gamma- radiation, of new radioactive elements, of artificial radioactivity, the neutron and positron and nuclear fission are reviewed as well as several adverse historical marks, such as the Manhattan project and some nuclear and radiological accidents. Nuclear energy generation in Brazil and the world, as an alternative to minimize environmental problems, is discussed, as are the medicinal, industrial and food applications of ionizing radiation. The text leads the reader to reflect on the subject and to consider its various aspects with scientific and technological maturity.

  10. Artificial economic agents

    Science.gov (United States)

    Terna, Pietro

    1992-09-01

    Neural networks are able to emulate economic subjects' behavior, without the utilization of a priori economic laws. This work states the possibility of explaining economic regularities about demand curve following connectionist models. Targets for training are generated by the model itself while it learns and acts with a cross-target method, i.e., the artificial neural network produces guesses both of the actions of the economic subject and of their effects. Actual effects are estimated by economic environment rules and results are used to train the effect guess mechanism; the evaluation of actions necessary to match guessed effects are, on the contrary, employed to train the decision mechanism (which guesses actions). Two kinds of learning -- short term and long term learning -- take place. The former only with local capability to react to the changes of the environment and the latter one with full capability to do it. For an observer the behavior produced by this kind of artificial agent (AA) matches the actions of a real agent as stated in economic handbooks, with goals and plans. Obviously, AA has no such symbolic entities, which are inventions of the observer. The assumption is that the observations of economists about real world agents' behavior suffer from the same bias. Economic regularities arising from present versions of the model encourage further developments, in particular toward the interaction of micro-models to build macroeconomic ones.

  11. Radioactivity in the Rhine - the LWA controls North-Rhine-Westphalian surface waters

    International Nuclear Information System (INIS)

    The State Authority for Water and Waste Management has been testing the Rhine and the most important surface waters of North-Rhine Westphalia for radioactivity ever since it was founded in 1969. Radiation exposure of human beings who use Rhine water is far below the permitted maximum values of the 'radiation protection ordinance'. Pollution of the Rhine and its tributaries in North-Rhine Westphalia with artificial radioactive substances has even slightly decreased over the past ten years; pollution of the River Emscher with natural radioactive material remained high, the Lippe River now contains less radium than before. (orig./PW)

  12. Measurements of radioactive and xenobiotic substances in the biological environment in the Netherlands 1986

    International Nuclear Information System (INIS)

    A brief survey of the results of detailed radioactivity measurements performed in the Netherlands during the period immediately after the Chernobylsk accident, and the risk analyses made on the basis of these results, are presented. The increase of the airborne radioactivity and the activity concentrations in surface water during the first week of May 1986 is demonstrated graphically. The radiation dose in 1986 due to artificial radioactivity has been calculated to be about 60 ?Sv for adults, 70 ?Sv for ten-year-old children and 110 ?Sv for one-year-old children. 54 figs.; 32 tabs

  13. Model description of radioactive materials migration in surface waters - input data

    International Nuclear Information System (INIS)

    Input data for computer models describing radioactive material proliferation in surface fresh water are classified into three groups. Group one consists of data on the radionuclide composition of radioactive effluents, the time schedule of release, the chemical composition of waste waters and their temperature. Group two consists of data necessary for the description of radioactive materials proliferation in natural or artificial water courses and in water basins. Group three consists of data on water uses leading to radiation burden to population, ie., fish, irrigation, farm animal watering, water sports and recreation. (H.S.)

  14. Assessment of the results of the Mediterranean coast side of the Permanent Observatory of Radioactivity (OPERA network) between 1992 and 2001

    International Nuclear Information System (INIS)

    After a presentation of the observation strategy (selection of indicators, spatial strategy, time strategy), of sampling, processing and gamma spectrometry measurement of samples, this report presents, analyses and comments the results obtained for the measurements of natural radioactivity, of artificial radioactivity related to 137Cs, 60Co and 106Ru activity in mussels, fishes and sediments sampled on the Mediterranean coast

  15. Radioactivity in food crops

    Energy Technology Data Exchange (ETDEWEB)

    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.

  16. Radioactivity in food crops

    International Nuclear Information System (INIS)

    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 137Cs, 40K, 90Sr, 226Ra, 228Ra, plutonium, uranium, total alpha, and total beta, but a few authors also reported data for 241Am, 7Be, 60Co, 55Fe, 3H, 131I, 54Mn, 95Nb, 210Pb, 210Po, 106Ru, 125Sb, 228Th, 232Th, and 95Zr. 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-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

  17. The ''invisible'' radioactive scale

    International Nuclear Information System (INIS)

    Production and up-concentration of naturally occurring radioactive material (NORM) in the petroleum industry has attracted steadily increasing attention during the last 15 years. Most production engineers today associate this radioactivity with precipitates (scales) and sludges in production tubing, pumps, valves, separators, settling tanks etc., wherever water is being transported or treated. 226Ra and 228Ra are the most well known radioactive constituents in scale. Surprisingly little known is the radioactive contamination by 210Pb and progeny 210Bi and 210Po. These are found in combination with 226Ra in ordinary scale, often in layer of non-radioactive metallic lead in water transportation systems, but also in pure gas and condensate handling systems ''unsupported'' by 226Ra, but due to transportation and decay of the noble gas 222Rn in NG/LNG. This latter contamination may be rather thin, in some cases virtually invisible. When, in addition, the radiation energies are low enough for not being detectable on the equipment outer surface, its existence has for most people in the industry been a secret. The report discusses transportation and deposition mechanisms, detection methods and provides some examples of measured results from the North Sea on equipment sent for maintenance. It is concluded that a regular measurement program for this type of contamination should be mandatory under all dismantling processes of transportation and fluid handling equipment for fluids and gases offshore and onshore

  18. Management on radioactive wastes

    International Nuclear Information System (INIS)

    The basic philosophy governing the radioactive waste management activities in India is to concentrate and contain as much activity as possible and to discharge to the environment only such of these streams that have radioactive content much below the nationally and internationally accepted standards. The concept of ''Zero Release'' is also kept in view. At Tarapur, the effluents are discharged into coastal waters after the radioactivity of the effluents is brought down by a factor 100. The effluents f?m Rajasthan reactors are discharged into a lake keeping their radioactivity well within permissible limits and a solar evaporation plant is being set up. The plant, when it becomes operational, will be a step towards the concept of ''Zero Release''. At Kalpakkam, the treated wastes are proposed to be diluted by circulating sea water and discharged away from the shore through a long pipe. At Narora, ion exchange followed by chemical precipitation is to be employed to treat effluents and solar evaporation process for total containment. Solid wastes are stored/dispsed in the concrete trenches, underground with the water proofing of external surfaces and the top of the trench is covered with concrete. Highly active wastes are stored/disposed in tile holes which are vaults made of steel-lined, reinforced concrete pipes. Gas cleaning, dilution and dispersion techniques are adopted to treat gaseous radioactive wastes. (M.G.B.)

  19. Radioactivity in the environment

    International Nuclear Information System (INIS)

    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

  20. Environmental radioactivity in Turkey, 2008

    International Nuclear Information System (INIS)

    In this report, the activity concentrations of natural and artificial radionuclides and gross alpha/beta activities measured in the environmental and food samples provided from Turkey's seven geographical regions within the environmental radioactivity monitoring program in 2008 as well radon activity concentrations measured in dwellings, and absorbed gamma dose rates in air obtained by means of car-borne measurement system (Mobysis) are presented. The activity concentrations of the natural and artificial radionuclides and gross alpha/beta activities in the samples were measured by using the gamma spectrometry, the alpha spectrometry, the liquid scintillation counter and gross alpha/beta counting system. The mean activity concentrations of 226Ra, 232Th and 40K in the analyzed surface samples are to be found as 26.0±0.9 Bq kg-1, 31.6±1.2 Bq kg-1 and438.5tively, while the mean activity concentration of the fission product 137Cs is to be found as 10.5±1.0 Bq kg-1. The mean absorbed gamma dose rate in outdoor caused from the external exposure from natural radionuclides in soil samples and the corresponding annual effective dose are evaluated as 49.4 nGy h-1 and 0.06 mSv y-1, repectively. The activitity concentrations of 238U, 232Th and 226Ra in the analyzed food samples are lowere than the Minimum Detectable Activity (MDA) while 134Cs radionuclide is not observed. The mean value of the activity concentration of 40K measured in food samples in seven categories is found as 129.8±11.3 Bq kg-1. While the values of the activity concentration of 137Cs are below the MDA except mushroom and hazelnut. The mean activity concentration of 137Cs and 90Sr radionuclides measured in the milk samples is 0.61 Bq L-1 and 0.05 Bq L-1, respectively. These values are lower than the limit value specified for foods subjected to control based on the regulation of the EU 737/90/EC. The total annual effective dose arising from the internal exposure due to radiation emitted by 40K, 137Cs and 90Sr radionuclides analyzed in the food samples are evaluated as 164.4 ?Sv. The values of the radon activity concentration measured in the dwellings in Turkey are below the limit value of 400 Bq m-3

  1. Interactions between Artificial Gravity, the Affected Physiological Systems, and Nutrition

    Science.gov (United States)

    Heer, Martina; Baecker, Nathalie; Zwart, Sara; Smith, Scott

    2006-01-01

    Malnutrition, either by insufficient supply of some nutrients or by overfeeding, has a profound effect on the health of an organism. Therefore, optimal nutrition is a necessity in normal gravity on Earth, in microgravity, and when applying artificial gravity to the human system. Reduced physical activity, such as observed in microgravity or bed rest, has an effect on many physiological systems, such as the cardiovascular, musculoskeletal, immune, and body fluids regulation systems. There is currently no countermeasure that is effective to counteract both the cardiovascular and musculoskeletal deconditioning when applied for a short duration (see Chapter 1). Artificial gravity therefore seems the simplest physiological approach to keep these systems intact. The application of intermittent daily dose of artificial gravity by means of centrifugation has often been proposed as a potential countermeasure against the physiological deconditioning induced by spaceflight. However, neither the optimal gravity level, nor its optimal duration of exposure have been enough studied to recommend a validated, effective, and efficient artificial gravity application. As discussed in previous chapters, artificial gravity has a very high potential to counteract any changes caused by reduced physical activity. The nutrient supply, which ideally should match the actual needs, will interact with these changes and therefore has also to be taken into account. This chapter reviews the potential interactions between these nutrients (energy intake, vitamins, minerals) and the other physiological systems affected by artificial gravity generated by an on-board short-radius centrifuge.

  2. Artificial Ligaments: Promise or Panacea?

    Science.gov (United States)

    Lubell, Adele

    1987-01-01

    The Food and Drug Administration has approved a prosthetic ligament for limited use in persons with damaged anterior cruciate ligaments (ACL). This article addresses ligament repair, ACL tears, current treatment, development of the Gore-Tex artificial ligament, other artificial ligaments in process, and arguments for and against their use.…

  3. Instructional Applications of Artificial Intelligence.

    Science.gov (United States)

    Halff, Henry M.

    1986-01-01

    Surveys artificial intelligence and the development of computer-based tutors and speculates on the future of artificial intelligence in education. Includes discussion of the definitions of knowledge, expert systems (computer systems that solve tough technical problems), intelligent tutoring systems (ITS), and specific ITSs such as GUIDON, MYCIN,…

  4. Sucrose compared with artificial sweeteners

    DEFF Research Database (Denmark)

    Sørensen, Lone Brinkmann; Vasilaras, Tatjana H; Astrup, Arne; Raben, Anne Birgitte

    2014-01-01

    There is a lack of appetite studies in free-living subjects supplying the habitual diet with either sucrose or artificially sweetened beverages and foods. Furthermore, the focus of artificial sweeteners has only been on the energy intake (EI) side of the energy-balance equation. The data are from a subgroup from a 10-wk study, which was previously published.

  5. Generalized Adaptive Artificial Neural Networks

    Science.gov (United States)

    Tawel, Raoul

    1993-01-01

    Mathematical model of supervised learning by artificial neural network provides for simultaneous adjustments of both temperatures of neurons and synaptic weights, and includes feedback as well as feedforward synaptic connections. Extension of mathematical model described in "Adaptive Neurons For Artificial Neural Networks" (NPO-17803). Dynamics of neural network represented in new model by less-restrictive continuous formalism.

  6. Multiple sample radioactivity detector

    International Nuclear Information System (INIS)

    The patent describes a detecting head assembly capable of detecting radioactive emissions from a source of radioactivity. The assembly may be used in the field of medical diagnostics and biomedical research for providing information relating to radioactive samples. The assembly consists of a number of drift chambers, below which a sample may be supported. A beta particle emitted from the sample ionizes the gas within the chamber, and negative ions are directed towards anode wires. The proximity of the tops of the drift chamber with the anode wires serves to prevent radiation received by any one drift chamber from being detected by any part of the electrode structure associated with another drift chamber. (U.K.)

  7. Radioactivity - superstition and science

    International Nuclear Information System (INIS)

    Fairy-tales, myths, superstition - how was it fair, when we could still be afraid for witches and goblins. Where demons floated and nicks danced, the dry science has spreaded and disenchanted the life. If there would not be things like radioactivity, against which can be struggled in the collective well being. Then it is bad, clear, or good, it heals sicks, also clear. But what is now correct? In his usual humorous way the author, Dr. Hermann Hinsch, explains by means of numerous examples the phenomenon ''radioactivity'' and its effects on life. Provocantly but illustratively he illuminates, which position radioactive radiation has in our life and how and where we have already met it wantedly or unwantedly. Perhaps we must then something less shudder, but something more realism at such theme is surely not harmful.

  8. 49 CFR 176.148 - Artificial lighting.

    Science.gov (United States)

    2010-10-01

    ...2010-10-01 2010-10-01 false Artificial lighting. 176.148 Section...Loading and Unloading § 176.148 Artificial lighting. Electric lights...arc lights, are the only form of artificial lighting permitted when...

  9. 21 CFR 886.3200 - Artificial eye.

    Science.gov (United States)

    2010-04-01

    ...2010-04-01 2010-04-01 false Artificial eye. 886.3200 Section 886.3200 Food and...Prosthetic Devices § 886.3200 Artificial eye. (a) Identification. An artificial eye is a device resembling the anterior portion...

  10. Beyond AI: Artificial Dreams Conference

    CERN Document Server

    Zackova, Eva; Kelemen, Jozef; Beyond Artificial Intelligence : The Disappearing Human-Machine Divide

    2015-01-01

    This book is an edited collection of chapters based on the papers presented at the conference “Beyond AI: Artificial Dreams” held in Pilsen in November 2012. The aim of the conference was to question deep-rooted ideas of artificial intelligence and cast critical reflection on methods standing at its foundations.  Artificial Dreams epitomize our controversial quest for non-biological intelligence, and therefore the contributors of this book tried to fully exploit such a controversy in their respective chapters, which resulted in an interdisciplinary dialogue between experts from engineering, natural sciences and humanities.   While pursuing the Artificial Dreams, it has become clear that it is still more and more difficult to draw a clear divide between human and machine. And therefore this book tries to portrait such an image of what lies beyond artificial intelligence: we can see the disappearing human-machine divide, a very important phenomenon of nowadays technological society, the phenomenon which i...

  11. Soft computing in artificial intelligence

    CERN Document Server

    Matson, Eric

    2014-01-01

    This book explores the concept of artificial intelligence based on knowledge-based algorithms. Given the current hardware and software technologies and artificial intelligence theories, we can think of how efficient to provide a solution, how best to implement a model and how successful to achieve it. This edition provides readers with the most recent progress and novel solutions in artificial intelligence. This book aims at presenting the research results and solutions of applications in relevance with artificial intelligence technologies. We propose to researchers and practitioners some methods to advance the intelligent systems and apply artificial intelligence to specific or general purpose. This book consists of 13 contributions that feature fuzzy (r, s)-minimal pre- and ?-open sets, handling big coocurrence matrices, Xie-Beni-type fuzzy cluster validation, fuzzy c-regression models, combination of genetic algorithm and ant colony optimization, building expert system, fuzzy logic and neural network, ind...

  12. Radioactivity and plumbum pollution

    International Nuclear Information System (INIS)

    This paper first indicates the five aspects to understand correctly the poisoning by radioactive plumbum: milling of nonferrous metal, development of mines, production of accumulator, discharge of waste gas from vehicles and radiation from building materials, as well as 'rubbish' from manufacture of plumbiferous equipment, and analyzes the seriousness of plumbum pollution (especially for children) along with the feature and symptom to plumbism. Then a lot of cases about the radioactive plumbum pollution are expounded so as to make a deeper understanding of plumbum pollution. Finally, some needed recognitions and prevention measures are put forward in different ways. (authors)

  13. Radioactive waste management

    International Nuclear Information System (INIS)

    First, some general informations are given about radioactive waste, e.g. arising of waste, classification, intermediate deposition and transport, as well as about the multi-barrier concept. Then, emphasis is laid on the internationally favoured vitrification of high-active waste. Safety requirements and the physical-chemical characteristics of the waste forms are described as are the different technical vitrification processes. Moreover, alternative solidification products such as ceramic materials and synthetic rocks were discussed. In addition, the worldwide technical concepts for the management and final disposal of radioactive waste are summarized. (orig./HP)

  14. The radioactive wastes management

    International Nuclear Information System (INIS)

    The different types of radioactive waste are presented in this paper in the frame of the official categories which take into account their dangerousness and the lifetimes of their radioactivity. It is indicated how the less dangerous of them are handled in France. The ways of protecting the environment from the more dangerous ones (high activity and long lifetimes) are object of studies. Scientific questions, in the field of chemistry and physical chemistry, related to the implementation of deep underground repository facilities with full respect of nuclear safety are presented. (authors)

  15. Radioactivity yesterday and today

    International Nuclear Information System (INIS)

    As an exhibition on the history of radioactivity from Homer to Oppenheimer has been organised in the Palais de la Decouverte in Paris, this article first recalls some atom characteristics and interactions between electrostatic forces within the atom. The author recalls how radioactivity has been unexpectedly discovered at the end of the 19. century, recalls the first works of characterization performed by Marie Curie and those performed by other scientists who perceived the opportunities for various applications. More recent works are also addressed like other forms of nucleus disintegrations, the generation of heavy ion beams, and double beta decay

  16. Radioactive wastes in Oklo

    International Nuclear Information System (INIS)

    The acceptance of the Nuclear Energy as electric power supply implies to give answer to the population on the two main challenges to conquer in the public opinion: the nuclear accidents and the radioactive wastes. Several of the questions that are made on the radioactive wastes, its are the mobility migration of them, the geologic stability of the place where its are deposited and the possible migration toward the aquifer mantels. Since the half lives of the radioactive waste of a Nuclear Reactor are of several hundred of thousands of years, the technical explanations to the previous questions little convince to the public in general. In this work summary the results of the radioactive waste generated in a natural reactor, denominated Oklo effect that took place in Gabon, Africa, it makes several thousands of millions of years, a lot before the man appeared in the Earth. The identification of at least 17 reactors in Oklo it was carried out thanks to the difference in the concentrations of Uranium 235 and 238 prospective, and to the analysis of the non-mobility of the radioactive waste in the site. It was able by this way to determine that the reactors with sizes of hardly some decimeter and powers of around 100 kilowatts were operating in intermittent and spontaneous form for space of 150,000 years, with operation cycles of around 30 minutes. Recent studies have contributed information valuable on the natural confinement of the radioactive waste of the Oklo reactors in matrixes of minerals of aluminum phosphate that caught and immobilized them for thousands of millions of years. This extracted information from the nature contributes guides and it allows 'to verify' the validity of the current proposals on the immobilization of radioactive wastes of a nuclear reactor. This work presents in clear and accessible form to the public in general on the secure 'design', operation, 'decommissioning' and 'storage' of the radioactive waste of the reactors that the nature put into operation in Oklo before the man appeared in the Earth. (Author)

  17. Radioactive material generator

    International Nuclear Information System (INIS)

    A radioactive material generator includes radioactive material in a column, which column is connected to inlet and outlet conduits, the generator being embedded in a lead casing. The inlet and outlet conduits extend through the casing and are topped by pierceable closure caps. A fitting, containing means to connect an eluent supply and an eluate container, is adapted to pierce the closure caps. The lead casing and the fitting are compatibly contoured such that they will fit only if properly aligned with respect to each other

  18. Your radioactive garden

    International Nuclear Information System (INIS)

    The booklet on radiation risks from nuclear waste is based on lectures given by the author at Westminster School (United Kingdom) and elsewhere during 1986. A description is given of naturally-occurring radioactivity, and the health risks due to this radiation. The types of radioactive wastes produced by the nuclear industry are described, including low-level wastes, short-lived and long-lived intermediate-level wastes, and high level wastes. These wastes are discussed with respect to their potential health risks and their disposal underground. (U.K.)

  19. Civilian radioactive waste management

    International Nuclear Information System (INIS)

    The safe management of high-level radioactive waste and spent nuclear fuel has been a matter of national concern for many years. Electric utilities have accumulated more than 10,000 metric tons of spent nuclear fuel, and it is estimated that by the end of the century there will be more than 40,000 metric tons of spent nuclear fuel in the United States requiring either a substantial expansion of storage capacity or a safe means of disposal. The DOE program for the management of radioactive waste is discussed

  20. Air chemistry and radioactivity

    International Nuclear Information System (INIS)

    The report is concerned with the expert discussion on the topic 'Waldschaeden durch Radioaktivitaet?' (Woods damaged by radioactivity?) since the publication of the book of the same title (Reichelt 1985). The discussion is concentrated on the debate about the hypothesis of the air-chemical effects, the significance of Reichelt's mapping of the forest damage and the air-chemical effect of ionizing radiation. The studies realized in connection with Reichelt's mapping results and the published calculations and measurements as to the topic of air chemistry and radioactivity are dealt with. (DG)