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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 Lough Foyle

    International Nuclear Information System (INIS)

    The purpose of this study was to assess the extent to which the marine environment of Lough Foyle, situated on the north coast of Ireland, has been affected by artificial radioactivity released from Sellafield. Although traces of plutonium, americium and radiocaesium from Sellafield are detectable in Lough Foyle, the concentrations in various marine media are significantly lower than those found along the NE coast of Ireland and in the western Irish Sea. The minute quantities of artificial radioactivity found in Lough Foyle are of negligible radiological significance

  3. Artificial radioactivity and its application

    International Nuclear Information System (INIS)

    The year 2000-2001 is the birth centenary year of Prof. Frederic Joliot Curie, who along with Irene Joliot Curie discovered artificial radioactivity in 1934. This opened up new challenges in the field of radiochemistry. In this paper, a brief discussion on historical background of radioactivity is given. This is followed by the methods of production of radioisotopes, general principles of using radiotracers. Some representative applications in various fields are discussed with the methodology and results. (author)

  4. 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.)

  5. 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

  6. 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.)

  7. Artificial radioactivity in Carlingford Lough

    International Nuclear Information System (INIS)

    The principal objective of this study was to assess whether radioactivity concentrations in a wide range of environmental materials from the Lough were enhanced above general levels found elsewhere along the east and north-east coasts of Ireland. Other objectives included an examination of gamma dose rates in air over inter-tidal sediments throughout the Lough and an examination of coastal soils to determine the extent of sea-to-land transfer of plutonium and , by inference, americium

  8. Artificial radioactivity of the Black Sea

    International Nuclear Information System (INIS)

    The artificial (technogenic) radioactivity of the Black Sea was studied before and after the Chernobyl event, both during the period of nuclear tests and the moratorium on such tests. Part I describes the forms of artificial radionuclides in seawater. Part II discusses the input into the Black Sea resulting from global fallouts. Part III is devoted to the Chernobyl radioecological consequences. The accumulation of radionuclides in bottom sediments and hydrobionts is considered in Part IV, while Part V is devoted to the modelling of the processes of radionuclide transport in Black Sea waters. 29 tabs., 52 figs., 135 refs

  9. 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.

  10. On the discovery of artificial radioactivity

    International Nuclear Information System (INIS)

    A review is presented of the elegant Joliot-Curie physical experiments which showed for the first time the possibility of producing artificial radioactive nuclei. An attempt has been made to explain the results of their equally elegant chemical experiments that unequivocally demonstrated the chemical change of elements by nuclear processes. These experiments are discussed in the light of present-day radiochemistry, keeping in mind the scientific and historical context in which they were originally performed. (orig.)

  11. 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)

  12. 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

  13. Artificial neutralization of radioactivity-I

    International Nuclear Information System (INIS)

    In this paper we have worked out effects of spherical pressure on conversion transition probabilities in light atoms i.e. Z=1,2,3.... For this purpose we have considered only a few conversion transitions i.e. EO, El, Ml both in free and spherically compressed muonic atoms. Our calculations have shown that conversion transition probabilities under compression increase (while Radiation transition probabilities decrease: to be published in-II). These effects led us to present the pioneering concept of an artificial neutralization of radioactivity. Actually in this process gamma-Ray mode of nuclear de-excitation is pressed into beta-mode of nuclear de-excitation. To deal with the problem we have used relativistic Quantum theory i.e. for lepton current and charge densities we have used Dirac's wave functions. (author)

  14. Natural and artificial radioactivity in Great Bratislava

    International Nuclear Information System (INIS)

    The results of the aviation measurement of the gamma-radiation are presented in the form of the maps of iso-lines of the concentration of the natural radioactive elements (potassium, uranium, thorium) and artificial radionuclides (cesium-137, cesium-134). From the obtained dates the maps of dose rate of the gamma-radiation in the air are calculated, of the dose equivalent rate and the map of the fraction of the dose equivalent rate from the natural elements potassium, uranium, thorium. The natural radioactivity of the minerals in the Great Bratislava region, especially for the extreme low values of the contain of the thorium, does not amount the average values of the radioactivity of the Earth crust. The area activity of cesium-137 are in the range 2 - 10 kBq.m-2 and cesium-134 is 1 - 2.5 kBq.m-2. From the point of view of the summary level of the external irradiation from the Earth surface the measured zone as relative even is evaluated, in the range 10-100 nSv.h-1. The total average level of the dose rate of the external irradiation of man (inclusively from the cosmic radiation 40-50 nSv.h-1) in the conditions of Bratislava is 100 nSv.h-1. The contribution of external component of the irradiation is 40-100 nSv.h-1 (0.1-0.3 mSv.y-1). The dose equivalent commitment of internal component from the cesium-137 is for the all age category of the population under the level negligible risk 0.01 mSv.y-1

  15. Monitoring artificial radioactivity in the Nordic countries

    International Nuclear Information System (INIS)

    This report describes the national systems for monitoring artificial radioactivity in the five Nordic countries (Denmark, Finland, Iceland, Norway and Sweden), including national similarities and differences regarding strategy and equipment. The backbone of the national system for early warning is a network of automatic gamma monitoring stations. It is complemented by manual stations and/or survey teams measuring in predetermined points. Air filter stations are used for nuclide specific analyses of aerosols and gaseous iodine. Fallout maps (especially for cesium-137) and isocurves (dose equivalent rates) are produced based on data from airborne measurements, monitoring stations, survey teams and environmental samples. All five countries have extensive programs for checking food contamination. Whole body counting and organ measurements are used to determine internal contamination. External contamination of people, vehicles, goods etc. is checked with survey meters and other equipment at checkpoints or as needed. Field measurements of various kinds complete the national systems. Current routines and systems for exchange of radiation data between the Nordic countries are summarized. A joint Nordic program for airborne measurements is suggested. Possible future development and planned improvements are discussed. (au)

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

    International Nuclear Information System (INIS)

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

  17. 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.)

  18. Natural and Artificial Radioactivity in Drinkingwater in Malaga, Spain

    International Nuclear Information System (INIS)

    The measurement of radioactivity in drinking water permits us to determine the exposure of the population to radiation from the habitual consumption of water. An intensive study of the water supply in the city of Malaga during 2002-2010 has been carried out in order to determine the gross alpha and gross beta activities and natural and artificial radionuclides present in drinking water. A database on natural and artificial radioactivity in water was created. The results indicated that a high percentage of the water sample contains a total gross alpha and beta concentration of less than 0.10 Bq/L and 1 Bq/L, respectively. The main objectives were: (1) to analyse gross alpha and gross beta activities and to know the statistical distributions; (2) to study the levels of natural and artificial radionuclides; (3) to determine a possible mathematical correlation between the radionuclides and several factors. (author)

  19. 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

  20. Natural and Artificial Radioactivity in Drinking Water in Malaga, Spain

    International Nuclear Information System (INIS)

    Water has a vast importance for numerous human activities, so that securing supplies of drinking water of a standard quality is becoming more and more difficult. The measurement of radioactivity in drinking water permits us to determine the exposure of the population to radiation from the habitual consumption of water. The occurrence of radionuclides in drinking water gives rise to internal exposure of humans, directly on the decay of radionuclides taken into the body through ingestion and inhalation and indirectly when they are incorporated as part of the food-chain The measurement of radioactivity in drinking water permits us to determine the exposure of population to radiation from the habitual consumption of water. An intensive study of the water supply in the city of Malaga during 2002-2010 has been carried out in order to determine the gross alpha activities, gross beta activities and natural and artificial radionuclides present in drinking water. A data base on natural and artificial radioactivity in water was produced. The results indicated that a high percentage of the water sample contains a total gross alpha and beta less than 0.10 Bq/l and 1 Bq/l respectively. The main objectives were: 1) to analyses gross alpha and gross beta activities and to know the statistical distributions. 2) to study the levels of natural and artificial radionuclides 3) to determine a possible mathematical correlation between the radionuclides and several factors.

  1. Natural and artificial radioactivity in coastal regions of UK

    International Nuclear Information System (INIS)

    The transport and bioaccumulation of natural and artificial radionuclides in the coastal regions of UK have been investigated. The magnitude of radionuclide concentration variation throughout the UK coastline has been quantified and where appropriate source terms have been identified. Sites bordering the Irish Sea show the highest levels of artificial radioactivity which are derived from past Sellafield discharges. Enhanced concentrations of natural radioactivity were found in all Whitehaven samples, in sediment at Blackhall Colliery near Hartlepool and in mussels at Aberdeen. Highest radionuclide concentrations were present in Whitehaven mussels - 3124Bqkg-1 dry weight of 210Po. Excluding sites bordering the Irish Sea, levels of natural radionuclides (210Pb, 210Po, 232Th, 238U) were greatly in excess of the artificial radionuclide concentrations in all sample types. The biological preference for accumulation of 210Po relative to its grandparent 210Pb is evident. 210Po/210Pb activity ratios range between 2 and 40 in mussels, winkles and seaweed but only between 0.24 and 1.3 in sediments and sea water. Radiologically, the highest radiation exposure to the public evident from the results would be from the ingestion of Whitehaven mussels (3.2mSv y-1), the greatest single contribution being from technologically enhanced 210Po. (Author)

  2. 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

  3. 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)

  4. 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.)

  5. 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)

  6. 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

  7. 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

  8. 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)

  9. Natural and artificial radioactivity determination of some medicinal plants

    International Nuclear Information System (INIS)

    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 (238U, 210Po) and gamma (214Pb-Bi, 210Pb, 40K and 137Cs) spectrometry. 238U ranged between dry-1; 210Po between dry-1; 214Pb-214Bi between dry-1; 210Pb between dry-1; 40K between 66.2 and 3582.0 Bq kgdry-1; 137Cs between dry-1. The percentage of 210Po extraction in infusion and decoction was also determined; the arithmetical mean value of percentage of 210Po extraction resulted 20.7 ± 7.5.

  10. 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)

  11. 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

  12. Problem of Induced Radioactivity in Food Products

    International Nuclear Information System (INIS)

    Radioactivity induced by irradiation of foods is caused by the interaction of high-energy radiation with nuclei of food elements. The induced activity is a function of the applied energy, the dose, the sample thickness and the chemical composition of the food. A prime condition for a prediction of the radioactivity induced by irradiation is therefore the knowledge of the chemical composition of the sample. Suitable experimental methods of food analysis are described. Electron and gamma rays are equivalent in the production of induced radioactivity. In the energy range of 0.05 to 10 MeV induced radioactivity is due to stimulation of isomers in (?, ?')-reactions. In this range the 107Ag(?, ?') 107mAg-reaction is responsible for the greatest part of the induced activity. Using a new simplified method of calculation the expected induced radioactivity is estimated, and it is concluded that the activity of these isomers presents no health hazard. By the same method the induced radioactivity in the energy range above 10 MeV, where besides ((?, ?') reactions the possibility of (?, n) reactions exists, is calculated for the principal foodstuffs. Methods for experimental verification of calculated activities are discussed. The magnitude of induced radioactivity due to single elements is compared with the total maximal permissible concentration (MPC) of nuclides in foods (10-7 ?Ci/g food). Factors which determine the maximum permissible radiation energy and dose are discussed. (author)

  13. 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.

  14. 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)

  15. 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.)

  16. 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

  17. Multiprotocol-induced plasticity in artificial synapses.

    Science.gov (United States)

    Kornijcuk, Vladimir; Kavehei, Omid; Lim, Hyungkwang; Seok, Jun Yeong; Kim, Seong Keun; Kim, Inho; Lee, Wook-Seong; Choi, Byung Joon; Jeong, Doo Seok

    2014-12-21

    We suggest a 'universal' electrical circuit for the realization of an artificial synapse that exhibits long-term plasticity induced by different protocols. The long-term plasticity of the artificial synapse is basically attributed to the nonvolatile resistance change of the bipolar resistive switch in the circuit. The synaptic behaviour realized by the circuit is termed 'universal' inasmuch as (i) the shape of the action potential is not required to vary so as to implement different plasticity-induction behaviours, activity-dependent plasticity (ADP) and spike-timing-dependent plasticity (STDP), (ii) the behaviours satisfy several essential features of a biological chemical synapse including firing-rate and spike-timing encoding and unidirectional synaptic transmission, and (iii) both excitatory and inhibitory synapses can be realized using the same circuit but different diode polarity in the circuit. The feasibility of the suggested circuit as an artificial synapse is demonstrated by conducting circuit calculations and the calculation results are introduced in comparison with biological chemical synapses. PMID:25373422

  18. 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

  19. 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.

  20. Radiation exposure due to artificial and natural radioactive nuclides

    International Nuclear Information System (INIS)

    The teaching unit presents information on the radiation exposure emanating from foodstuffs and natural or artificial nuclides in our environment. The material is prepared for teaching purposes, also indicating means of action for prevention of radiation exposure. (DG)

  1. 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

  2. Concrete structure for controlling induced radioactivity

    International Nuclear Information System (INIS)

    If neutron fluxes generated from a radiation source such as a nuclear reactor are irradiated to concrete structures, induced radioactivity is produced. Since the induced radioactivity continues to release radiation-rays (gamma rays) even when the irradiation of neutrons is terminated, there is a problem of operators' exposure, etc. particularly upon opening a nuclear reactor in periodical inspection. In the present invention, silicon rubber neutron shielding layers or polyethylene neutron shielding layers are formed at the surface of the concrete structures of a nuclear facility on the side of the radiation source. The countings of ?-rays from these shielding material layers are about 1/100 of usual concretes. Accordingly, neutron irradiation to the concrete structures can be prevented, by which induced radioactive containing long half-life time nuclides from the concrete structures can be suppressed. (T.M.)

  3. 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)

  4. 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)

  5. 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.

  6. Natural and artificial alpha radioactivity of platinum isotopes

    International Nuclear Information System (INIS)

    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 176Pt to the excited level of 172Os, and the rare, quite recently observed, case of the natural alpha decay of 190Pt to the first excited level of 186Os. Comparison with other alpha decay half-life estimates for the naturally occurring platinum isotopes has also been presented.

  7. NATURAL AND ARTIFICIAL RADIOACTIVITY IN IMPORTED FISHERY PRODUCTS

    Directory of Open Access Journals (Sweden)

    R. Cavallina

    2013-02-01

    Full Text Available Considering the growing public concern over marine environmental quality, a program of monitoring radionuclids in imported fishery products has been established. The analyses have been performed by gamma spectrometry allowing the rapid detection of many artificial radionuclides such as 137Cs, 134Cs and 40K. The data obtained show Cs radionuclides levels within expected limits. The detection of natural radionuclide K showed different levels in the same fishery product as they came from different sea areas.

  8. The artificial radioactivity in Bechet-Dabuleni area, five years of survey

    International Nuclear Information System (INIS)

    The Bechet-Dabuleni area is placed in the southern part of Romania, in the Danube zone, near the Nuclear Power Plant from Kozlodui (Bulgaria). Here there is a very important agricultural area, with small and also big farms where for irrigation the Danube water is used. The purpose of the study was was long term surveillance of the artificial radioactivity for the main foodstuffs. It has been investigated the radioactive content of the following foodstuffs from this area: vegetables (potatoes, carrots, onion, etc.), fruits (apples, pears, apricots, peaches) and cereals (wheat, barley). It has also been determined the radioactive content of the irrigating water from the Danube River. (author)

  9. Investigation and assessment on artificial radioactivity level in soil in Shanghai

    International Nuclear Information System (INIS)

    Artificial radioactivity level in soil of Shanghai and in sediment of Huangpu River have been investigated during 1989 to 1990. The results showed that the levels were about the same as that in other places over China. The annual individual effective dose of 137Cs in soil of Shanghai was estimated

  10. Levels of artificial radioactivity in milk samples from two different ecosystems of the Extremadura region

    International Nuclear Information System (INIS)

    The levels of artificial radioactivity were determined in goat and cow milk samples collected from 1988 to 1990 in centres of population belonging to two Extremadura ecosystems in which there are situated the Almaraz nuclear power plant and the nuclear waste disposal site of El Cabril. (author)

  11. Safety aspects of the use of artificial radioactive tracers in hydrology

    International Nuclear Information System (INIS)

    The paper reviews the safety aspects of the use artificial radioactive tracers in hydrology. Basic radiation safety considerations, official approval and detailed safety planning for carrying out radiotracer study, safety in actual operational procedures such as transport of radiotracers to the field, injection of tracer and post injection surveillance are discussed. (author). 3 refs

  12. 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.)

  13. Evolution of artificial radioactivity in Channel sediments, 1971-1975

    International Nuclear Information System (INIS)

    The radioactivity of sediments of the Channel and Atlantic shores was measured by Ge-Li diode spectrometry on gross and fine samples collected from 1971 to 1975. The effects of the fuel reprocessing plant at La Hague, the central point of the monitored area, were clearly demonstrated only from 1974 on the gross fraction for 106Ru, 95Zr, 125Sb, 144Ce, and on the fraction smaller than 28?m for 106Ru, 95Zr, 125Sb, 144Ce, 65Zn, 103Ru, 110Ag, 134Cs, 141Ce, 155Eu. As regards 137Cs, in spite of rather significant discharges, no evident effects could be detected by measurements. Some aspects of in situ retention processes of radionuclides on sediments were demonstrated by comparing sediment activities versus discharged activities and by considering desorption characteristics

  14. Some regularities in artificial radioactivity distribution in rain droplets

    International Nuclear Information System (INIS)

    Investigations of the sup(210)Po distribution in rain droplets were carried and the methods of the determination of parameters characterizing the rain droplets were described. Conclusions from the material of 9 natural experiments being performed in 1972-1980 were drawn. The ranges of the modal, predominant and effective radii of raindrops were measured and their mean values were calculated. It was shown that by increase of modal, predominant and effective radii the number of raindrops with these radii in comparison with the all raindrops decreased. During a rain the droplets of optimal sizes (r=0.68-1.02 mm) existed; their number, mass and amount of the sup(210)Po washed out by them were maximal. A dependence of raindrops tracer radioactivity on the size and mass of raindrops was described

  15. Monitoring of natural and artificial radioactivity in integrated iron and steel flux

    International Nuclear Information System (INIS)

    Possible concentration of radioactivity in iron and steel process implies necessity of radiometric measurements to identify the natural and/or artificial radioisotopes in iron, steel, and raw materials, intermediate, finite products and offal. This paper presents the technology of measurements using single- and multi- channel analyser with high resolution gamma spectrometry system. A low cost measurement for selecting potentially interesting radioactive samples is first performed and then a complete spectrometric analysis is undertaken. We checked the procedure for several descendants of natural series (e.g. 214 Pb, 214 Bi, 238 U, and 40 K) and several artificial isotopes currently used in iron and steel process control (e.g. 241 Am, 60 Co, 137 Ce, and 110 Ag). (Author)

  16. Detecting artificial airborne radioactivity: on-line monitoring of external dose rate near an aerosol filter

    International Nuclear Information System (INIS)

    An early warning method based on external dose rate monitoring near an aerosol filter can be used to detect artificial airborne radioactivity. A theory is presented for calculating the external dose rate in the measurement geometry involved. Airborne radionuclides and radionuclides collected by the filter and deposited on the ground are considered. Delay time from the arrival of a radioactive cloud to a tentative warning level of 0.4?Gy.h-1 is calculated for two cases: for a constant activity concentration of 137Cs and for a group of fission products. The simulations indicate that, in terms of activity concentrations, a warning level of -3 of artificial airborne radionuclides can be attained. This activity concentration corresponds roughly to an external dose rate of 1 nG.h-1, which is about 2 orders of magnitude below a typical, natural, ground-level dose rate. (Author)

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

    OpenAIRE

    Kharissova, Oxana V.; Miguel A. Méndez-Rojas; Boris I. Kharisov; 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...

  18. Detection of pulmonary aspiration by radioactive measurements of bronchial material in artificially ventilated infants

    International Nuclear Information System (INIS)

    Detection of pulmonary aspiration of gastric contents by radioactive measurements of bronchial material was performed in 13 artificially ventilated infants (14 studies) after ingestion of 99m-technetium sulfure colloide. 10/13 had strong clinical suspicion of recurrent pulmonary aspiration. 10 out of 14 examinations were positive (71%). This technique is more sensitive than scintigraphic methods described in literature and particularly adapted to these patients

  19. 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.

  20. Development of artificial radioactivity in the French environment during the past 50 years and related doses; effect of the current operation of nuclear facilities

    International Nuclear Information System (INIS)

    The activities of artificial radionuclides in the environment have being strongly decreasing since 50 years. Nowadays the activities of 3H and 14C widely predominate, but they cannot be still considered as artificial radionuclides, except nearby the nuclear installations where they constitute the most abundant radioactive releases. In terrestrial environment this influence is limited to the surroundings of 5 sites, although most of nuclear sites and nuclear medical centers are involved in the contamination of the aquatic environment downstream the releases and in the Channel. Since 1987 the doses to the French population have been mainly induced by 14C and 137Cs. (author)

  1. 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)

  2. Individual and social risk due to natural and artificial environmental radioactivity in Greece

    International Nuclear Information System (INIS)

    Two sets of cases of natural versus artificial radioactivity risk assessment for the Greek population are presented in this paper. In the first set, the variations of the individual risk due to the external exposure to the terrestrial gamma rays of natural origin and those of the 137Cs deposited after the Chernobyl accident are compared. In the second set the risk due to the internal exposure of the patients of the major Greek radon spas is compared with the risk of the Athens region inhabitants resulting from a characteristic accident of the Greek Research Reactor. (author)

  3. Standard test bench for calibrating instruments used to measure natural or artificial radioactive airborne particulates

    International Nuclear Information System (INIS)

    An aerodynamic calibration device, known as ICARE, has been set up in France at the Saclay Research Centre to certify instruments used to measure natural or artificial airborne radioactive particulate contamination or radon. ICARE can calibrate passive detectors and monitors with sampling air flow-rates of less than 60 m3/h. The adjustment of such parameters as 222Rn daughters volume activity, attached fraction and equilibrium factor, and the volume activity and size of ? or ? emitter carrying aerosols, allows realistic conditions to be obtained. ICARE complies with monitor test method standard currently under development by the International Electrotechnical Commission. (author)

  4. Standard test bench for calibrating instruments used to measure natural or artificial radioactive airborne particulates

    International Nuclear Information System (INIS)

    An aerodynamic calibration device, known as ICARE, has been set up in France at the Saclay Research Centre to certify instruments used to measure natural or artificial airborne radioactive particulate contamination or radon. ICARE can calibrate passive detectors and monitors with sampling air flow-rates of less than 60 m3/h. The adjustment of such parameters as 222Rn daughters volume activity, attached fraction and equilibrium factor, and the volume activity and size of ? or ? emitter carrying aerosols, allows realistic conditions to be obtained. ICARE complies with monitor test method standard currently under development by the International Electrotechnical Commission

  5. The use of artificial sorbents for radioactivity monitoring of water basins of Belarus

    International Nuclear Information System (INIS)

    A possibility of using artificial sorbents to study radionuclide behaviour in a water has been shown. With these sorbents a pollution degree has been determined in a water of lakes of different types with a minimal economical expenditures and operatively. Inconstancy of influenced factors in summer time doesn't permit to determine the activity of cesium 137 in a water authentically, but it gives the opportunity to reveal the pattern of radioactive cesium distribution by the area of lake aquatic system and by it's depth and so to permit the monitoring of lake basins station

  6. 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)

  7. Solutes problems and main results in the area of natural and artificial radioactivity

    International Nuclear Information System (INIS)

    The list of research problems and main results in natural and artificial radioactivity monitoring in the Slovak Republic is presented.The mean values of 78 000 measurements of natural radioactivity are: potassium 1.6 %, uranium 3.3 ppm, thorium 9.4 ppm, relation of Th/U 2.8, Th/K 5.8, and U/K 2.1. Mean dose rate for Slovakia is 63.3 nGy/h.The mean activity of cesium-137, measured on 5500 points, is 2200 Bq/m2 that is mean dose rate 3.5 nGy/h. The arithmetic mean of concentration of uranium in underground waters of Slovakia is .0034 mg/dm3, mean volume activity of radium 222 is 0.048 Bq/dm3 and of radon-222 is 15.51 Bq/dm3

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

    International Nuclear Information System (INIS)

    In the present work, the enhancement of radioactivity due to rainfall in the Aegean Sea using floating measuring systems was observed and quantified. The data were acquired with a NaI underwater detection system, which was installed on a floating measuring system at a depth of 3 m. The results of natural and artificial radioactivity are discussed taking into account the rainfall intensity and wind direction. The activity concentration of 214Bi increased up to (991±102) Bq/m3 after strong rainfall in the North Aegean Sea in winter (humid period) with east wind direction. On other hand, the maximum activity concentration reached the level of (110±10) Bq/m3 in summer (dry period) during south winds

  9. 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)

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

    International Nuclear Information System (INIS)

    Environmental biomonitoring has demonstrated that organisms such as crustaceans, fish and mushrooms are useful to evaluate and monitor both ecosystem contamination and quality. Particularly, some mushroom species have a high capacity to retain radionuclides and some toxic elements from the soil and the air. The potential of mushrooms to accumulate radionuclides in their fruit-bodies has been well documented. However, there are no studies that determine natural and artificial radionuclide composition in edible mushrooms, in Brazil. Artificial (137Cs) and natural radioactivity (40K, 226Ra, 228Ra) were determined in 17 mushroom samples from 3 commercialized edible mushroom species. The edible mushrooms collected were Agaricus sp., Pleurotus sp. and Lentinula sp. species. The activity measurements were carried out by gamma spectrometry. The levels of 137Cs varied from 1.45 ± 0.04 to 10.6 ± 0.3 Bq kg?1, 40K levels varied from 461 ± 2 to 1535 ± 10 Bq kg?1, 226Ra levels varied from 14 ± 3 to 66 ± 12 Bq kg?1 and 228Ra levels varied from 6.2 ± 0.2 to 54.2 ± 1.7 Bq kg?1. 137Cs levels in Brazilian mushrooms are in accordance with the radioactive fallout in the Southern Hemisphere. The artificial and natural activities determined in this study were found to be below the maximum permissible levels as established by national legislation. Thus, these mushroom species can be normally consumed by the population without any apparent risks to human health. - Highlights: ? 137Cs, 40K, 226Ra and 228Ra in edible mushroom samples. ? There are very few data about natural radionuclides in mushrooms. ? The radionuclide activities were below the national maximum permissible levels. ? Mushrooms can be consumed by the population without any apparent risks.

  11. Survey and assessment on artificial radioactivity level in Shanghai atmospheric environment

    International Nuclear Information System (INIS)

    Survey of artificial radioactivity level in Shanghai atmospheric environment took place during Sept. 1989 to Nov. 1991. The result showed that the total ?-radioactivity concentration of aerosol in one-day samples and seven-day samples were 9.3 x 10-2 Bq/m3 and 2.6 x 10-2 Bq/m3 respectively, among which the concentrations of 90Sr-6 Bq/m3, 137Cs-5 Bq/m3; total ?-radioactivity in precipitation was 0.78 Bq/m3, among which 90Sr was 1.6 x 10-2 Bq/m2. d, 137Cs-3 Bq/m2. d, tritium vapor was 0.09 Bq/m3. The result of statistical analysis and assessment showed that there were no obvious differences at sampling points around Shanghai Municipality, but the seasonal variation showed that in the spring and winter seasons, the concentration was higher than that in the summer and autumn seasons

  12. OBSERVATIONAL SCAN-INDUCED ARTIFICIAL COSMIC MICROWAVE BACKGROUND ANISOTROPY

    International Nuclear Information System (INIS)

    Reliably detecting the cosmic microwave background (CMB) anisotropy is of great importance in understanding the birth and evolution of the universe. One of the difficulties in CMB experiments is the domination of measured CMB anisotropy maps by the Doppler dipole moment from the motion of the antenna relative to the CMB. For each measured temperature, the expected dipole component has to be calculated separately and then subtracted from the data. A small error in dipole direction, antenna pointing direction, sidelobe pickup contamination, and/or timing synchronism can introduce a significant deviation in the dipole-cleaned CMB temperature. After a full-sky observational scan, the accumulated deviations will be structured with a pattern closely correlated with the observation pattern with artificial anisotropies, including artificial quadrupole, octupole, etc., on large scales in the final CMB map. Such scan-induced anisotropies on large scales can be predicted by the true dipole moment and observational scan scheme. Indeed, the expected scan-induced quadrupole pattern of the Wilkinson Microwave Anisotropy Probe (WMAP) mission is perfectly in agreement with the published WMAP quadrupole. With the scan strategy of the Planck mission, we predict that scan-induced anisotropies will also produce an artificially aligned quadrupole. The scan-induced anisotropy is a common problem for all sweep missions and, like the foreground emissions, has to be removed from observed maps. Without doing so, CMB maps from COBE, WMAP, and Planck are not reliable for studying the CMB anisotropy.

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

    OpenAIRE

    Bolaji B. Babatunde; Francis D. Sikoki; Ibitoruh Hart

    2015-01-01

    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 a...

  15. Electromagnetically induced transparency on a single artificial atom

    OpenAIRE

    Abdumalikov, Jr., A. A.; Astafiev, O.; Zagoskin, A. M.; Pashkin, Yu. A.; Nakamura, Y.; Tsai, J. -S.

    2010-01-01

    We present experimental observation of electromagnetically induced transparency (EIT) on a single macroscopic artificial "atom" (superconducting quantum system) coupled to open 1D space of a transmission line. Unlike in a optical media with many atoms, the single atom EIT in 1D space is revealed in suppression of reflection of electromagnetic waves, rather than absorption. The observed almost 100 % modulation of the reflection and transmission of propagating microwaves demonstrates full contr...

  16. Application of artificial neural networks on the characterization of radioactive waste drums

    International Nuclear Information System (INIS)

    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

  17. The quick distinguishing of the artificial radioactive contamination of the air by ?-decay proportional method

    International Nuclear Information System (INIS)

    The principles of the distinction of artificial radioactive contamination of air by '?-decay proportional method' are described and a brief introduction to the instruments designed according to the principles of this method is given. From the data processing it is concluded as follows: The concentration of ?-aerosol is 7.49 Bq/m3 (approx 2.0 x 10-13Ci/L) sampling for one hour, the amount of sampling air is 3.36 m3. And 60 minutes after sampling, the determination level is 1.82 Bq/m3 (approx 4.9 x 10-14Ci/L). For 150 minutes duration, the level is 1.77 Bq/m3 (approx 4.8 x 10-14 C.Ci/L)

  18. 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

  19. 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)

  20. Artificial neural networks modeling of radioactive contamination of the Techa river

    International Nuclear Information System (INIS)

    For analyzing the anomalously high radioactive contamination of the Techa river in August 2004, when the content of 90Sr in Muslyumovo section line exceeded 50 Bq/l, the dynamics of its concentration in water of the Techa river and the level of the V-11 water body were simulated using artificial neural networks. The conclusion was made about existence of a certain concealed factor actuating in certain time moments and resulting in essential water level decrease in the V-11 water body, which cannot be explained based on the precipitation and evaporation balance. Effect of the factor is closely related to water consumption in the left-bank canal. The assumption is made that concurring anomalously high radioactive contamination of the Techa river water in summer of 2004 and water level decrease in the V-11 water body, unaccountable from the balance of precipitation and evaporation, were due to discharge of contaminated water from the V-11 to the left-bank by-pass canal

  1. 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.

  2. 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.)

  3. 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)

  4. 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)

  5. Applicability of artificial intelligence to reservoir induced earthquakes

    Science.gov (United States)

    Samui, Pijush; Kim, Dookie

    2014-06-01

    This paper proposes to use least square support vector machine (LSSVM) and relevance vector machine (RVM) for prediction of the magnitude (M) of induced earthquakes based on reservoir parameters. Comprehensive parameter (E) and maximum reservoir depth (H) are used as input variables of the LSSVM and RVM. The output of the LSSVM and RVM is M. Equations have been presented based on the developed LSSVM and RVM. The developed RVM also gives variance of the predicted M. A comparative study has been carried out between the developed LSSVM, RVM, artificial neural network (ANN), and linear regression models. Finally, the results demonstrate the effectiveness and efficiency of the LSSVM and RVM models.

  6. Assessment of artificial radioactive contamination of Jeju soil through 137Cs concentration measurements

    International Nuclear Information System (INIS)

    Various artificial radioactive isotopes were distributed to the earth atmosphere due to the nuclear weapon tests in 1950's and 1960's and the NPP accident. Thus these radioactive isotopes are detected even in regions, which are away from nuclear facilities. In order to estimate these effects, this study measured the 137Cs concentrations in Jeju island. 137Cs was chosen as its relatively long half-life of 30.2 years makes the element last longer. Through the literature survey, the characteristics of the soil in Jeju were reviewed and eight sampling sites were selected by regional and soil-color groups. The soil samples were prepared by the standard sampling method. Using the HPGe detector and MCA(Multi-Channel Analyser), the gamma-ray spectrum analyses were carried out and the 137Cs concentrations were determined. Simultaneously, pH and O.M.C.(Organic Matter Content) analyses were performed as they are important factors affecting the 137Cs concentrations. The measured 137Cs concentrations spread 2.333-9.402 Bq/kg and the measurement errors were estimated to be 1.36%. These results seem to be similar to the national 137Cs level and correspond to about 1/2000 of the limiting values described in the Atomic Energy Act Decree, showing that the effects of 137Cs to human and environments are negligible. The 137Cs level correlated with the O.M.C. showed a clear proportionality. Thus the organic matter in soil absorbs 137Cs, limiting the mobility of 137Cs and resulting high 137Cs level. Also the comparisons of the results with similar study performed by KINS for nuclear facilities sites show the higher 137Cs concentrations of Jeju soil, which again can be explained by the high O.M.C. of Jeju soil as it had been formed by the volcanic activities and the volcanic ashes are less efficient in removing the organic matters

  7. studies on the fixation of chemical and radioactive contaminants by natural and artificial compounds

    International Nuclear Information System (INIS)

    the main objective of the work presented in this is to study the adsorption of U(VI), Cr(VI) and Gd (lll) from aqueous medium using modified sorel's cement as artificial adsorbents. the thesis is classified into three chapters; namely ,introduction ,experimental and results and discussion. the first chapter,introduction,includes chemical and radioactive contaminant, some aspects of the properties and aqueous chemistry of uranium, chromium and gadolinium . the separation of different pollutant and their methods of separation based on the types of adsorbents, and the theoretical background of adsorption isotherms, kinetics and ion diffusion as well as literature survey which is related to the present work are given.the second chapter, experimental,contains the different materials employed, their chemical purity, and a detailed description for instruments used are given.the third chapter.results and discussionincludes the experimental results obtained and their interpretation .this chapter is classified into three main parts; namely, characterization, equilibrium and kinetic investigations

  8. 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)

  9. 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.

  10. Induced radioactivity in the ESRF storage ring.

    Science.gov (United States)

    Berkvens, P

    2005-01-01

    The new French radiation protection legislation requires the definition of the zoning of accelerator facilities with respect to radioactive waste. This activation inside the ESRF 6 GeV storage ring is essentially due to photonuclear reactions. This paper describes the first results of Monte Carlo calculations that were started to prepare this zoning. The electron beam losses inside the storage ring, required to calculate saturation activities, are described. Results for the activation of the air inside the ring tunnel and of the cooling water are presented. The activation of accelerator components is illustrated with the results of the activation of the stainless steel vessels in a standard cell and in a cell with higher losses due to the presence of a vertical scraper. The amount of activation is compared with clearance levels given in the European directive 96/29/Euratom. PMID:16381770

  11. 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.

  12. 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)

  13. 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)

  14. 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.)

  15. 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)

  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. 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)

  18. 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.

  19. 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

  20. 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)

  1. 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)

  2. Anthrax toxin-induced rupture of artificial lipid bilayer membranes

    Science.gov (United States)

    Nablo, Brian J.; Panchal, Rekha G.; Bavari, Sina; Nguyen, Tam L.; Gussio, Rick; Ribot, Wil; Friedlander, Art; Chabot, Donald; Reiner, Joseph E.; Robertson, Joseph W. F.; Balijepalli, Arvind; Halverson, Kelly M.; Kasianowicz, John J.

    2013-08-01

    We demonstrate experimentally that anthrax toxin complexes rupture artificial lipid bilayer membranes when isolated from the blood of infected animals. When the solution pH is temporally acidified to mimic that process in endosomes, recombinant anthrax toxin forms an irreversibly bound complex, which also destabilizes membranes. The results suggest an alternative mechanism for the translocation of anthrax toxin into the cytoplasm.

  3. Levels of natural and artificial radioactivity in sediments in the Eastern Black Sea of Turkey

    International Nuclear Information System (INIS)

    Sediments samples collected from the Eastern Black Sea in 1993 from 15 sampling stations of different depths have been analyzed. Natural and artificial radionuclide activity levels in offshore sediment samples from the Eastern Black Sea in Turkey are reported about seven years after the Chernobyl accident. The purpose of this paper is to follow up the earlier study and present results for the distributions of radionuclides in sediments of the Black Sea. (author). 14 refs., 2 figs., 2 tabs

  4. 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.

  5. 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)

  6. A comparison of artificial saliva and pilocarpine in radiation-induced xerostomia

    International Nuclear Information System (INIS)

    Twenty patients with radiation-induced xerostomia were entered into a prospective randomized crossover study comparing a mucin-based artificial saliva (Saliva Orthana) and a mouthwash containing pilocarpine (5 mg three times a day). Overall the patients found that the pilocarpine mouthwash was more effective than the artificial saliva in relieving their symptoms (p = 0.04), and 47 per cent of the patients wanted to continue with this treatment after the study had finished. (author)

  7. 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)

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

    Science.gov (United States)

    Faghihi, R; Mehdizadeh, S; Sina, S

    2011-04-01

    Fars province is a large populated large province located in the southwest of Iran. This work presents a study of natural and radioactivity levels in soil samples of this province. For this purpose, 126 samples were gathered from different regions of the province and analysed by gamma spectroscopy to quantify radioactivity concentrations of radionuclides using a high-purity germanium detector and spectroscopy system. The results of this investigation show the average concentrations of 271 ± 28 Bq kg(-1), 6.37 ± 0.5 Bq kg(-1), 14.9 ± 0.9 Bq kg(-1) and 26.3 ± 1.9 Bq kg(-1) for (40)K, (137)Cs, (232)Th and (238)U in soil, respectively. Finally, baseline maps were established for the concentrations of each of the radionuclides in different regions. The absorbed dose rate and the annual effective dose (AED) were also calculated for the radionuclides according to the guidelines of UNSCEAR 2000. The average AED from the radioactivity content of soil in this province was found to be 39.9 ± 1.8 ?Sv. PMID:21081518

  9. 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.

  10. 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.

  11. 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.

  12. Low-induced radioactivity ultrahigh vacuum system using aluminum alloy

    International Nuclear Information System (INIS)

    In the High Energy Physics Laboratory in Tsukuba, the development of an ultrahigh vacuum system made of aluminum was successfully achieved for the first time in the world, and at present, the TRISTAN ring is under construction. The discovery and verification that aluminum and its alloys are very advantageous for reducing radioactivity exposure became the opportunity to begin, and the research has been advanced, as the result, also the rate of released gas was able to be improved as compared with conventional stainless steel. The application to nuclear fusion equipment, semiconductor production facility such as molecular beam epitaxy and analysis equipment as well as accelerators is promoted. The induced radioactivity of five kinds of metallic sheets was compared, and the change of the material for the vacuum system of particle accelerators to aluminum alloy was planned. The newly developed ultrahigh vacuum system made of aluminum alloys is described, and its application to the particle accelerator TRISTAN is explained. In the application to nuclear fusion experimental apparatus, the use of Al-Li-Mg alloy may resolve the problems. The findings obtained at the Laboratory are shown. (Kako, I.)

  13. 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.

  14. Muon-induced production of radioactive isotopes in scintillation detectors

    CERN Document Server

    Hagner, T; Heisinger, B; Oberauer, L; Schönert, S; Von Feilitzsch, F; Nolte, E

    2000-01-01

    The production of radioactive isotopes in scintillation detectors by muons and their secondary shower particles has been studied experimentally at the SPS muon beam at CERN. This paper shows the results obtained in cross-section measurements on liquid scintillator targets, especially on /sup 12/C which is the most relevant target in these organic materials. Their energy dependence has been deduced from the cross-sections determined at two muon energies 100 and 190 GeV. Based on the measured cross-sections the muon-induced background rates for the forthcoming solar neutrino experiments BOREXINO and KAMLAND have been calculated for different energy regions that are relevant for solar neutrino physics. (23 refs).

  15. Studies of artificial radioactivity in the coastal environment of northern Scotland: a review

    International Nuclear Information System (INIS)

    This review brings measurements that 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, 136Cs, 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 that contribute to the study area are described. Some transfer mechanisms that operate between different media for different radionuclides are discussed, and the radiological significance of the observed radionuclide concentrations is briefly described. (Author)

  16. 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)

  17. Natural and artificial enhanced radioactivity in the Lake Kerkini and the River Strymon (Greece)

    International Nuclear Information System (INIS)

    Measurements of naturally occurring and artificially enhanced radionuclides in the Lake Kerkini at Serres Region, Northern Greece, were made in estimating cumulative inputs originating from Bulgaria and transferred by the River Strymon passing through the lake. Radium-226 as well as Radium-228 ranged between 60 and 80 Bq.kg-1 dry weight in the reservoir sediments. Potassium-40 ranged between 560 and 720 Bq.kg-1 dry weight. Cesium-137 ranged between 60 and 140 Bq.kg-1 dry weight, due to the fallout from the Chernobyl accident. The natural radionuclides were uniformly distributed in the basin of the Lake Kerkini, while 137Cs was differentially distributed because of recycling effects caused by the aquatic plants and organisms in biota and the movement of brought material from high elevations surrounding the lake basin. (Author) 2 tabs., 3 figs., 9 refs

  18. 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

  19. 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.

  20. 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%.

  1. 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

  2. Natural and artificial radioactivity in surface waters of the Ebro river basin (Northeast Spain)

    International Nuclear Information System (INIS)

    A radiological characterisation of surface waters of the Ebro river basin was carried out during November 1994. For this purpose, 75 water samples were collected from points distributed throughout the Ebro river basin. Analysis included gross alpha and gross beta activities, relevant natural radionuclides (40K, 226Ra, 234,238U -uranium total-) and several artificial radionuclides (3H, 90Sr and radiocaesium). Mean gross alpha and gross beta activities in surface waters of the river's main course were 0.095±0.004 and 0.213±0.012 Bq l-1, respectively. Mean activities of 40K, 226Ra and uranium (total) were 0.132±0.009, 0.0282±0.0008 and 0.053±0.006 Bq l-1, respectively. Regarding artificial radionuclides, the mean 90Sr activity was 6.6±0.3 mBq l-1, 3H was detected in 8% of the samples, and radiocaesium was not detected in any sample. It is estimated that almost 100% of gross alpha and 97% of gross beta activities of surface waters in the Ebro river came from natural sources. Furthermore, results showed that the geological setting, large cities, agricultural areas and dams strongly influence the occurrence of natural radionuclides. Contamination from nuclear power plants located along the river was not detected. Finally, we estimated that the annual dose equivalent due to the hypothetical ingestion of Ebro river waters was 7.59 ?Sv y-1, which represented only 0.3% of the average annual effective dose attributable to natural background radiation in the area

  3. 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

  4. 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)

  5. Artificial and natural radioactivity measurements in the vicinity of Ghana nuclear research reactor (GHARR-1)

    International Nuclear Information System (INIS)

    Radioactivity concentrations of 226Ra, 232Th, 40K and 137Cs in soil and water samples around the Ghana Research Reactor-1 (GHARR-1) and the immediate surroundings have been investigated using gamma spectrometry. The primary aim of this study was to establish baseline radioactivity levels in the environs of GHARR-1. The average activity concentration in soil for 226Ra, 232Th, 40K and 137Cs were 19.8 Bqkg-1, 40.4 Bqkg-1, 95.3 Bqkg-1 and 1.5 Bqkg-1 respectively. For the water samples the average activity concentration of 226Ra was 2.15 Bql-1, 232Th was 0.61 Bql-1, 40K was 10.75Bql-1 and 137Cs was 0.47 Bql-1. The 226Ra and 232Th concentrations compare quite well with world averages, whilst the 40K concentration was lower than the world average. The activity concentrations of 137Cs observed in the samples are within the range of background. concentrations. The estimated average annual effective dose from external exposure to soil and ingestion of water samples was calculated to be 0.64 mSv. The estimated outdoor external gamma dose rate measured in air ranged from 10-430 nGyh-1 with an average value of 41 nGyh-1 which is lower than the worldwide average value of 60 nGyh-1. In the case of the water samples, the average annual effective value was higher than the WHO guideline value of 0.1 mSvy-1 (author)

  6. 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.

  7. 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.

  8. 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)

  9. 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)

  10. Radioactivity

    International Nuclear Information System (INIS)

    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.)

  11. 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

  12. 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...

  13. 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)

  14. Estimation of absorbed gamma dose in air due to natural and artificial radioactivity of soil. Resume of Ph.D thesis

    International Nuclear Information System (INIS)

    This is an extended abstract of the Ph. D. thesis devoted to the measurements of air absorbed gamma doses due to natural and artificial radioactivity in soil. It contains a summary of the four chapters of the thesis. The first chapter presents problems related to the measurement of natural and artificial radioactivity coming from soil contamination due to nuclear explosions or nuclear accidents. The natural and artificial radionuclides which usually contaminate the soil are reviewed. The chapter two presents the original contribution of the author in the field of the methods of soil sampling and NaI(Tl) gamma spectrometry analysis of radioactive samples. Also the results of the measurements carried out in 10 counties in Romania are here reported. The natural radionuclides measured were Ra-226, Th-232, and K-40, while the artificial radionuclides were Cs-137 and Cs-134. In the third chapter the radioactivity levels are reported as absorbed air gamma doses due to presence of 137 Cs and 134 Cs in soil. Also here the effective dose equivalents estimated for the population of the 10 counties are presented. In the concluding chapter four a discussion is given concerning the dose levels measured following the Chernobyl nuclear accident as function of time elapsed from the accident and of depth of soil sampling and of soil type. It is shown that the dose levels which affected the population in the studied zones are within the values of radioprotection standards in Romania. These data were used as input to solve the problem of the biological effects of low doses on the population health. (M.I.C.). 7 Figs., 10 Tabs., 73 Refs

  15. 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...

  16. 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

  17. 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

  18. 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.)

  19. 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)

  20. 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.

  1. 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)

  2. 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...

  3. Earthquake-induced landslide-susceptibility mapping using an artificial neural network

    OpenAIRE

    Lee, S.; Evangelista, D. G.

    2006-01-01

    The purpose of this study was to apply and verify landslide-susceptibility analysis techniques using an artificial neural network and a Geographic Information System (GIS) applied to Baguio City, Philippines. The 16 July 1990 earthquake-induced landslides were studied. Landslide locations were identified from interpretation of aerial photographs and field survey, and a spatial database was constructed from topographic maps, geology, land cover and terrain mapping units. Factors that influence...

  4. 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

  5. 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.

  6. Exploring thermally induced states in square artificial spin-ice arrays

    International Nuclear Information System (INIS)

    We present a methodology to explore experimentally the formation of thermally induced long-range ground-state ordering in artificial spin-ice systems. Our novel approach is based on the thermalization from a square artificial spin-ice array of elongated ferromagnetic nanoislands made of a FeNi alloy characterized by a Curie temperature about 100 K lower than that of Permalloy (Ni81Fe19), which is commonly used for this kind of investigation. The decrease in M(T) when the sample is heated close to its Curie temperature reduces the shape anisotropy barrier of each island and allows us to bring the artificial spin-ice pattern above the blocking temperature of the islands, thus ‘melting’ the spin-ice system, without damaging the sample. The magnetization configuration resulting from the thermal excitation of the islands and the frustrated dipolar interactions among them can be then imaged by magnetic force microscopy or any other kind of magnetic microscopy imaging after cooling down the sample back to room temperature. This thermally induced melting–freezing protocol can be repeated as many times as desired on the same sample and the heating and cooling parameters (max T, heating and cooling rates, number of cycles, application of external fields) varied at will. Thereby, the approach proposed here opens up a pathway to the systematic experimental study of thermally induced frozen states in artificial spin-ice systems, which have been the subject of many recent theoretical studies due to their interesting physical properties but, because of the difficulties in obtaining them in real samples and in a controlled manner, remain experimentally an almost completely unexplored terrain. (paper)

  7. 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.).

  8. Radioactivity

    International Nuclear Information System (INIS)

    This bulletin supplements UK radioactivity data published in Chapter 4 of the Digest of Envirnomental Protection and Water Statistics No 11 1988 (HMSO 1989). The data are presented in three sections: (a) annual emissions (gaseous liquid and solid) by site, and trends in volume; (b) annual concentrations, particularly of drinking water, strontium 90 and caesium 137; (c) estimation of collective doses from fish and shellfish consumption in the U.K. and Europe, and summary of committed dose equivalents to a one-year old infant from milk consumption in the U.K. (UK)

  9. 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.

  10. 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)

  11. 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.)

  12. Induced radioactivity in interior beam probe for low-energy proton cyclotron

    International Nuclear Information System (INIS)

    Both theoretical analysis and Monte-Carlo simulation on induced radioactivity in the copper measuring probe irradiated by proton beams with energy of 11 MeV and intensity of 50 ?A have been demonstrated. Saturated activities of various kinds of radioactive nuclides obtained by these two methods were compared. The comparison indicates that the Monte-Carlo method conducted by software FLUKA can provide good simulation accuracy and complete consideration in nuclear reaction, and both the direct and indirect radioactivity under different irradiation time can be calculated simultaneously. The method can also provide accurate analysis and prediction on the induced radioactivity in different measuring probes under proton irradiation, which will provide a reference for design, exchange and disposal of the probes. (authors)

  13. 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.

  14. Studies of muon-induced radioactivity at NuMI

    International Nuclear Information System (INIS)

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

  15. Pinning of a single Abrikosov vortex in superconducting Nb thin films using artificially induced pinning sites

    International Nuclear Information System (INIS)

    Artificial structures were intentionally introduced into Nb films in order to study the interaction of a single Abrikosov vortex with pinning sites caused by these known defects. A vortex trapped on one of these structures or defects can be induced to move either by thermal depinning or by pushing on the vortex with a transport current in one of the films. The resulting motion, in turn, can be followed by observing the changes in the Fraunhofer-like interference pattern of a cross-strip Josephson junction having the thin film as one leg of the junction. Artificial pinning sites were successfully created by depositing Fe balls on the surface of a previously characterized thin film. Attempts to create artificial pinning sites by depressing the order parameter with a thin strip of Au on the surface of the Nb were not successful. There was no correlation between the location of trapped vortices and the location of the Au line. In a separate measurement, Lorentz-force-depinning studies for several intrinsic pinning sites in the thin film show that a transport current in the top film will depin a vortex in the top film with about one-tenth the current needed in the bottom film to depin the same vortex. (c) 2000 The American Physical Society

  16. 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: â–º We perform on-site quantitative LIBS analysis of soil samples. â–º We demonstrate that univariate analysis is not convenient. â–º We exploit artificial neural networks for LIBS analysis. â–º Spectral lines other than the ones from the analyte must be introduced

  17. 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.

  18. Status and perspectives of the surveillance of artificial radioactivity in the environment in Europe and of the international exchange of radiological data

    International Nuclear Information System (INIS)

    After the Chernobyl accident systems for the surveillance of artificial radioactivity and for the international exchange of radiological data have been upgraded or established all over Europe. They include both site-specific as well as nation-wide systems and programmes. The modules of the systems for the surveillance of artificial radioactivity are on-line networks (mostly gamma dose rate and air concentration) with fixed stations, mobile units (ground based and airborne) and specialized laboratories which are capable of performing as a minimum requirement high resolution gamma ray spectrometric measurements of various types of environmental samples. In general, the technical standard of the European surveillance systems is very high. The systems have been designed mostly to meet national requirements. As a consequence, the situation in Europe as a whole is inhomogeneous and there is a need for quality assurance programmes at the European level. The establishment of the existing systems for the international exchange of radiological data and information is based on bilateral, multilateral and international agreements. They cover the whole spectrum from site specific bilateral agreements for NPPs near national borders to international agreement between all member states of the European Union (ECURIE). (author)

  19. 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.

  20. 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.

  1. Evaluation of induced radioactivity in structural material of Toshiba Training Reactor 'TTR1'

    International Nuclear Information System (INIS)

    A decommissioning programme for the Toshiba Training Reactor (TTR1), a swimming pool type reactor used for reactor physics experiments and material irradiation, was started in August 2001. As a part of the programme, induced radioactivity in structural material was evaluated using neutron flux data obtained with the three-dimensional Sn code TORT. Induced activity was calculated with the isotope generation code ORIGEN-79 using activation cross section data created from multi-group library based on JENDL-3. The obtained results for radioactivities such as 60Co, 65Zn, 54Mn and 152Eu were compared with measured ones, and the present calculational method was confirmed to have enough accuracy. (authors)

  2. 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).

  3. Diffusion of the 241Am ? 237Np decay chain limited by their elemental solubilities in the artificial barriers of high-level radioactive waste repositories

    International Nuclear Information System (INIS)

    A mathematical analysis of the diffusion of the 241Am ? 237Np decay chain in the artificial barrier of a high-level radioactive waste repository is presented. First, analytical solutions obtained are for the space- and time-dependent concentration of 241Am in the artificial barrier and the time-dependent amount of americium precipitated at the surface of the waste glass, based on the assumption of the congruency of the radionuclides with solubility-limited dissolution of the glass matrix. The effects of solubility sharing with coexisting 243Am are considered. Transport and precipitation of 237Np in the artificial barrier are analyzed by dividing the time domain into a small time domain, where the 241Am concentration is so large that 237Np precipitation is dominant, and a large time domain, where the 241Am becomes negligible and the precipitation region shrinks by diffusion from the precipitation front. The equation for the movement of the precipitation front is obtained. As the overpack lifetime increases, the effect of neptunium precipitation becomes less significant. With a lifetime longer than ?6000 yr, an earlier model, where neptunium is treated as a mother nuclide and the precipitation occurs only at the glass surface, can be used

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

    Science.gov (United States)

    Ye?ilkanat, Cafer Mert; Kobya, Ya?ar

    2015-09-01

    In this study, radiological distribution of gross alpha, gross beta, (226)Ra, (232)Th, (40)K, and (137)Cs for a total of 40 natural spring water samples obtained from seven cities of the Eastern Black Sea Region was determined by artificial neural network (ANN) method. In the ANN method employed, the backpropagation algorithm, which estimates the backpropagation of the errors and results, was used. In the structure of ANN, five input parameters (latitude, longitude, altitude, major soil groups, and rainfall) were used for natural radionuclides and four input parameters (latitude, longitude, altitude, and rainfall) were used for artificial radionuclides, respectively. In addition, 75 % of the total data were used as the data of training and 25 % of them were used as test data in order to reveal the structure of each radionuclide. It has been seen that the results obtained explain the radiographic structure of the region very well. Spatial interpolation maps covering the whole region were created for each radionuclide including spots not measured by using these results. It has been determined that artificial neural network method can be used for mapping the spatial distribution of radioactivity with this study, which is conducted for the first time for the Black Sea Region. PMID:26307690

  5. Rapid method of gamma-ray does rates for distinction between natural and artificial radioactive nuclides using portable NaI(Tl) scintillation measurement system

    International Nuclear Information System (INIS)

    When evaluating an environmental ?-ray dose rates, it is important to determine the individual contributions of both natural and artificial radioactive nuclides to the overall measured rate. In areas where nuclear contamination is suspected, however, it can be difficult to rapidly ascertain these relative contributions. This paper describes the use of a portable NaI(T1) scintillation spectrometer to quickly and accurately measure ?-ray dose rates at 16 locations in Japan, in order to construct a contamination map on an emergency basis. The survey data showed that, in locations with differing energy distributions, there were noticeable correlations between the total ?-ray dose and the count rates within the specific energy ranges of 1400 - 3000, 1650 - 3000 and 1800 - 3000 keV, and these correlations differed markedly between natural and artificial nuclides. These observations suggested that the artificial nuclide contribution to the ?-ray dose rate could be calculated using the correlations, and subsequent analysis of the data confirmed that this was possible. The resulting estimates were accurate to within approximately 3.3, 0 and 10% within the energy ranges of 1400 - 3000, 1650 - 3000 and 1800 - 3000 keV as the 30 nGy/h, respectively. (author)

  6. 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)

  7. Artificial radioisotopes in hydrological investigation

    International Nuclear Information System (INIS)

    The application of artificial radioisotopes in the solution of hydrological problems is reviewed. The devices with sealed radioactive sources to measure sedimentary rock concentration brought by river flows in a suspended state to measure the thickness and density of sedimentations are developed. Radioactive indicators are another way of application of artificial radioactive isotopes. The need in such indicators is conditioned by a wide variability of appropriate parameters of water systems in time and space. Artificial radioactive indicators are widely used in the research of many problems of civil construction, connected with water. The limitations in the use of radioactive substances in many countries are an obstacle to a wider application of artificial radionuclides

  8. Percutaneous Ethanol Injection via an Artificially Induced Right Hydrothorax for Hepatocellular Carcinoma in the Hepatic Dome

    International Nuclear Information System (INIS)

    To evaluate the efficacy of sonographically (US) guided percutaneous ethanol injection (PEI) via an artificially induced right hydrothorax (transthoracic PEI) to treat US-invisible hepatocellular carcinoma (HCC) in the hepatic dome. Five cirrhotic patients with US-invisible HCC in the hepatic dome, who were poor surgical candidates, underwent transthoracic PEI. An artificial right hydrothorax was created by instilling 500 ml saline, and absolute ethanol was injected transhydrothoracically into the hepatic dome lesion under local anesthesia. The success and complications were assessed radiologically. The patients were followed up serologically and radiologically for 12-44 (mean 28.4) months. Twenty-five hydrothoraces were induced. All hydrothoraces enabled US visualization of the entire hepatic dome. Eight of the nine small lesions were treated successfully by the treatment. Two of the three local recurrences were eradicated by repeat transthoracic PEI. One large lesion was treated by a combination of transthoracic and regular PEI. The only complication was one clinically insignificant pneumothorax. Induction of a right hydrothorax is feasible and safe. The hydrothorax enables US visualization of the entire hepatic dome and permits US-guided PEI for HCC in the hepatic dome that otherwise would not be possible

  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.

  10. 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.)

  11. 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

  12. Manifestation of the influence of releases of artificial long-lived radionuclides seen against the background of global radioactive contamination of the Atlantic Ocean and related seas

    International Nuclear Information System (INIS)

    The authors note an analogy in the behaviour of artificial and natural radionuclides in the ocean. A seasonal tendency is observed in the variations of 90Sr concentrations due to global fall-out in surface waters of the North Atlantic (200N-700N latitude), and an empirical formula is suggested to describe the observed seasonality. The results are given of 90Sr, 137Cs and 134Cs determinations carried out by the authors in the surface waters of the North Sea, and of 90Sr and 137Cs determinations made in surface waters of the southern part of the Baltic Sea. A comparison with data from the literature shows that the release of radioactive materials beyond the norms laid down in the London Dumping Convention of 1952 led to serious contamination of the North Sea, to levels in fact which were considerably in excess of the global radioactive contamination for 1963. Through the normal processes of turnover and interchange of water masses, the resultant radioactive impurities entered the Baltic Sea. In 1979 the influx of 137Cs from the North Sea into the Baltic was ten times greater than the influx through river discharge. However, in surface waters near the straits in the south and south-west part of the Baltic no increased concentration of 137Cs was found in 1979. (author)

  13. Development of a method for plasma - induced combustion of intermediate to low-level radioactive waste

    OpenAIRE

    Nachtrodt, Frederik

    2013-01-01

    This work demonstrates that the plasma - induced combustion of intermediate to low-level radioactive waste is a suitable method for volume reduction and stabilization. Weaknesses of existing facilities can be overcome with novel developments. Plasma treatment of LILW has a high economical advantage by volume reduction for storage in final repositories.

  14. 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

  15. 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

  16. 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.)

  17. 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.

  18. Earthquake-induced landslide-susceptibility mapping using an artificial neural network

    Directory of Open Access Journals (Sweden)

    S. Lee

    2006-01-01

    Full Text Available The purpose of this study was to apply and verify landslide-susceptibility analysis techniques using an artificial neural network and a Geographic Information System (GIS applied to Baguio City, Philippines. The 16 July 1990 earthquake-induced landslides were studied. Landslide locations were identified from interpretation of aerial photographs and field survey, and a spatial database was constructed from topographic maps, geology, land cover and terrain mapping units. Factors that influence landslide occurrence, such as slope, aspect, curvature and distance from drainage were calculated from the topographic database. Lithology and distance from faults were derived from the geology database. Land cover was identified from the topographic database. Terrain map units were interpreted from aerial photographs. These factors were used with an artificial neural network to analyze landslide susceptibility. Each factor weight was determined by a back-propagation exercise. Landslide-susceptibility indices were calculated using the back-propagation weights, and susceptibility maps were constructed from GIS data. The susceptibility map was compared with known landslide locations and verified. The demonstrated prediction accuracy was 93.20%.

  19. New estimation of La Hague contribution to the artificial radioactivity of Norwegian waters (1992-1995) and Barents Sea (1992-1997)

    International Nuclear Information System (INIS)

    A release of 10,000 GBq per month of a conservative radionuclide into the central part of the English Channel gives rise to activities (in Bq m-3) of 6 8-89 at Goury, 50-70 in Cherbourg (5 and 30 km from the waste outlet of La Hague), 25-40 in the Straits of Dover, 4-5 at the entrance of the Norwegian Channel and 1-3 at the entrance of the Barents Sea. Taking account of La Hague releases and transit times of 17 and 36 months, a calculation of the contribution of La Hague to the artificial radioactivity of the entrance to the Norwegian Channel and the Barents Sea is given

  20. 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

  1. 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)

  2. 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

  3. 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

  4. 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 (<∼10 cm) consist of 0-90 degree turning element, and covers two-phase flow regime up to churn-turbulent flow. (author)

  5. Induced radioactivity in air and water at medical accelerators

    International Nuclear Information System (INIS)

    Activation of air and water has been evaluated at the 10 and 15 MeV linear electron accelerator facilities. At 15 MeV irradiation, the activity of 10-min-half-life 13N was observed in the case of the air in the glove box. Air and water samples were also bombarded by 250 MeV protons and 400 MeV/u carbon, and the irradiation dose was 10 Gy at the isocenter. Upon the ion-chamber monitoring of the air sampled from the glove box, 15O, 13N, and 11C activities were mainly observed. At the end of proton and carbon irradiation, the activity of the water was found to be about 10 kBq·cm-3 and several kBq·cm-3, respectively. From the decay analysis of the induced activity in water, 15O, 13N, and 11C were detected. (author)

  6. Artificial radioactivity in edible parts of giant clam mollusc from Mururoa atoll from 1967 to 1990. Health physics aspect

    International Nuclear Information System (INIS)

    Radionuclides concentration by giant clams is associated with feeding habit. It's also a main food for polynesian atolls inhabitants, elsewhere than Mururoa island because this mollusc is not consumed like all the other fishery products from this atoll lagoon. Nevertheless measurements of ten artificial radionuclides are performed in edible parts of giant clams fished from Mururoa lagoon since the beginning of nuclear tests. The decay of radionuclides concentration is described versus time. To go further on we have computed the dose-equivalent for internal exposure of an eventual giant clams eater. It is estimated that the resulting risk of malignancy is below than 1 per 10 000

  7. 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)

  8. Giant Controllable Magnetization Changes Induced by Structural Phase Transitions in a Metamagnetic Artificial Multiferroic

    Science.gov (United States)

    Bennett, S. P.; Wong, A. T.; Glavic, A.; Herklotz, A.; Urban, C.; Valmianski, I.; Biegalski, M. D.; Christen, H. M.; Ward, T. Z.; Lauter, V.

    2016-01-01

    The realization of a controllable metamagnetic transition from AFM to FM ordering would open the door to a plethora of new spintronics based devices that, rather than reorienting spins in a ferromagnet, harness direct control of a materials intrinsic magnetic ordering. In this study FeRh films with drastically reduced transition temperatures and a large magneto-thermal hysteresis were produced for magnetocaloric and spintronics applications. Remarkably, giant controllable magnetization changes (measured to be as high has ~25%) are realized by manipulating the strain transfer from the external lattice when subjected to two structural phase transitions of BaTiO3 (001) single crystal substrate. These magnetization changes are the largest seen to date to be controllably induced in the FeRh system. Using polarized neutron reflectometry we reveal how just a slight in plane surface strain change at ~290C results in a massive magnetic transformation in the bottom half of the film clearly demonstrating a strong lattice-spin coupling in FeRh. By means of these substrate induced strain changes we show a way to reproducibly explore the effects of temperature and strain on the relative stabilities of the FM and AFM phases in multi-domain metamagnetic systems. This study also demonstrates for the first time the depth dependent nature of a controllable magnetic order using strain in an artificial multiferroic heterostructure. PMID:26940159

  9. Rainfall and earthquake-induced landslide susceptibility assessment using GIS and Artificial Neural Network

    Directory of Open Access Journals (Sweden)

    Y. Li

    2012-08-01

    Full Text Available A GIS-based method for the assessment of landslide susceptibility in a selected area of Qingchuan County in China is proposed by using the back-propagation Artificial Neural Network model (ANN. Landslide inventory was derived from field investigation and aerial photo interpretation. 473 landslides occurred before the Wenchuan earthquake (which were thought as rainfall-induced landslides (RIL in this study, and 885 earthquake-induced landslides (EIL were recorded into the landslide inventory map. To understand the different impacts of rainfall and earthquake on landslide occurrence, we first compared the variations between landslide spatial distribution and conditioning factors. Then, we compared the weight variation of each conditioning factor derived by adjusting ANN structure and factors combination respectively. Last, the weight of each factor derived from the best prediction model was applied to the entire study area to produce landslide susceptibility maps.

    Results show that slope gradient has the highest weight for landslide susceptibility mapping for both RIL and EIL. The RIL model built with four different factors (slope gradient, elevation, slope height and distance to the stream shows the best success rate of 93%; the EIL model built with five different factors (slope gradient, elevation, slope height, distance to the stream and distance to the fault has the best success rate of 98%. Furthermore, the EIL data was used to verify the RIL model and the success rate is 92%; the RIL data was used to verify the EIL model and the success rate is 53%.

  10. Time and energy resolved runaway measurements in TFR from induced radioactivity

    International Nuclear Information System (INIS)

    A time and energy resolved measurement of the radioactivity induced by runaway electrons in proper samples has been developped in TFR. The data give an information on the confinement time of these electrons, which appears to be strongly dependent on the toroidal field, suggesting the onset of a magnetic turbulence at lower fields. Observations showing that the runaway electrons deeply penetrate into the limiter shadow are also reported

  11. 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.

  12. 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)

  13. Reaction dynamics induced from light weakly-bound radioactive ion beams at near-barrier energies

    International Nuclear Information System (INIS)

    This work presents an overview of the latest experiments performed to study the reaction dynamics induced from light weakly-bound Radioactive Ion Beams on medium-mass and heavy targets at near-barrier energies. Production reactions, secondary beam intensities and experimental results on elastic scattering, transfer, breakup and fusion processes are presented and discussed. A comparative analysis of fusion and reaction cross section data for different projectile-target combinations is finally given. (author)

  14. Radioactivity induced in air and concrete shielding in the JAERI electron linac

    International Nuclear Information System (INIS)

    The secondary radiation activates the high-energy accelerator facilities, air, cooling water and building structures and surrounding soils. The induced radioactive materials become sources for public exposures. In addition, these will produce radioactive wastes in its decommissioning. Estimations of radiation exposures and its protections for the induced radioactive nuclei will be key issues for constructions of large-scale accelerators and its operations in future. This paper describes the investigation on compositions and spatial distributions of induced radioactive nuclei produced in the electron linear accelerator of JAERI, Tokai. The electron linear accelerator has the history of 33 years and the final specification of the accelerating energy of 120 MeV, the peak current of 500 mA, the pulse widths from 0.02 to 2 ?s and the repetition rates from 10 to 600 pps. We measured 11C, 13N and 15O by using the plastic scintillation counters, ionizing chambers, and radio-gas-chromatography. Ratios of the saturated activities of 13N and 15N as a function of the angle from the beam axis were obtained. Time-dependent chemical compositions of 13N and 15N up to the irradiation time 60 min was also estimated using the electromagnetic cascade code. We made core-borings of 4.5 cm in diameter and 150 cm in depth on the shielding concrete. Gamma rays counting rates as a function of the depth of concrete was obtained on the samples. Furthermore, the concentrations of gamma-rays emitters were identified. These results indicate that the spatial dependence is very important in relation with the un-isotropic propagation of the beam particles. Much more accumulations of this type of data are necessary to elucidate behaviors of induced radio nuclei. (Tanaka, T.)

  15. 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)

  16. 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

  17. The extreme Rhone River flood of December 2003 (South East France) - Consequences on the translocation of artificial radioactive contaminants onto the flooded areas

    International Nuclear Information System (INIS)

    Full text: In recent years, great progress has been made in reducing the direct emission of artificial radioactivity and other contaminants into the environment from industrial sources. However the transport and fate of previously-released pollutants is still of great concern. In particular, it is now recognized that certain natural sinks, such as soils and deposits of sediment in streams, rivers and oceans, can entrain the contaminants for long periods of time, only to serve as sources of contamination at some later date. Such a phenomenon was first observed in the Irish Sea after sharp decreases in releases from the spent fuel reprocessing plant in Sellafield. In rivers, one of the primary mechanisms for the remobilization of contaminated deposits is thought to be major flood events. As a result of climate change, floods have become more abundant and more destructive in many regions of the globe including Europe. Then substantial changes in risk of translocation of sediments and associated contaminants onto flooded areas is expected. At the beginning of December 2003 an exceptional meteo climatic event led to an extreme Rhone River flood that flooded almost 500 km2 of the low Rhone valley. Flooding waters entrained a large amount of sediments that have deposited on agricultural soils and urban areas. Therefore particle reactive contaminants such as radionuclides may have been partly translocated from the River onto a large terrestrial area through remobilisation of contaminated fluvial sediments. The soils of the low Rhone valley are labelled with 2000 Bq m-2 for 137Cs, 50 Bq m-2 for 239+240Pu and 1.5 Bq m-2 for 238Pu as mean values. Based on our previous studies we estimate than radioactive inputs onto flooded areas might reach about 500 Bq m-2 for 137Cs. Nevertheless, a great spatial heterogeneity is expected depending on both the mass and nature of the sedimentary deposits. Several field cruises were performed until February 2004 to estimate the spatial spreading of sedimentary deposits. The deposit thinness were measured at almost 140 reference points within 3 main flooded areas whom one includes the Arles city. 87 samples were collected and are analysed for their sedimentary nature and organic matter content. About fifty percent of these samples are analysed regarding artificial radionuclides (gamma-emitters), organic contaminants and trace metals. Finally, a map of additional contamination of flooded areas during December 2003 is expected together with an evaluation of the consequences of such extreme flood events. (author)

  18. The extreme Rhone River flood of December 2003 (south east France) - Consequences on the translocation of artificial radioactive contaminants onto the flooded areas

    International Nuclear Information System (INIS)

    Full text: In recent years, great progress has been made in reducing the direct emission of artificial radioactivity and other contaminants into the environment from industrial sources. However the transport and fate of previously-released pollutants is still of great concern. In particular, it is now recognized that certain natural sinks, such as soils and deposits of sediment in streams, rivers and oceans, can entrain the contaminants for long periods of time, only to serve as sources of contamination at some later date. Such a phenomenon was first observed in the Irish Sea after sharp decreases in releases from the spent fuel reprocessing plant in Sellafield. In rivers, one of the primary mechanisms for the remobilization of contaminated deposits is thought to be major flood events. As a result of climate change, floods have become more abundant and more destructive in many regions of the globe including Europe. Then substantial changes in risk of translocation of sediments and associated contaminants onto flooded areas is expected. At the beginning of December 2003 an exceptional meteo climatic event led to an extreme Rhone River flood that flooded almost 500 km2 of the low Rhone valley. Flooding waters entrained a large amount of sediments that have deposited on agricultural soils and urban areas. Therefore particle reactive contaminants such as radionuclides may have been partly translocated from the River onto a large terrestrial area through remobilisation of contaminated fluvial sediments. The soils of the low Rhone valley are labelled with 2000 Bq m-2 for 137Cs, 50 Bq m-2 for 239+240Pu and 1.5 Bq m-2 for 238Pu as mean values. Based on our previous studies we estimate than radioactive inputs onto flooded areas might reach about 500 Bq m-2 for 137Cs. Nevertheless, a great spatial heterogeneity is expected depending on both the mass and nature of the sedimentary deposits. Several field cruises were performed until February 2004 to estimate the spatial spreading of sedimentary deposits. The deposit thinness were measured at almost 140 reference points within 3 main flooded areas whom one includes the Arles city. 87 samples were collected and are analysed for their sedimentary nature and organic matter content. About fifty percent of these samples are analysed regarding artificial radionuclides (gamma-emitters), organic contaminants and trace metals. Finally, a map of additional contamination of flooded areas during December 2003 is expected together with an evaluation of the consequences of such extreme flood events. (author)

  19. 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)

  20. [Induced radioactivity in irradiated foods by X ray or gamma ray].

    Science.gov (United States)

    Miyahara, Makoto

    2007-01-01

    In the course of the archival studies on safety of irradiated foods by the US Army, experimental records conducted by Glass & Smith, and Kruger & Wilson were investigated, based on our experimental experience. Food irradiation by Co-60 or 4 approximately 24MeV X ray can induce small amount of radioactivity in the foods. The principal mechanisms of the nuclear reactions are (gamma, n). The resulting nuclear products found in irradiated target solutions were Ba-135m, Pb-204m, Hg-199m, Ag-107m,Ag-109m, Cd-111m,Cd-113m, Sn-117m, Sn-119m, Sr-87m, Nb-93m, In113m, In-115m, Te-123m, Te-125m, Lu-178m Hf-160m by the (gamma, n) reaction. The total radio-activities in beef, bacon, shrimp, chicken, and green beans were counted at 60 days after irradiation by Cs-137, Co-60, and fuel element. The activities more than background were found in irradiated bacon and beef by Co-60. and activities were found in most foods when foods were irradiated by high energy X ray and the fuel element. The results were understood as the neutron activation by (gamma, n) or (n, gamma) reaction. Therefore, high energy X ray and spent fuel element were not used for food irradiation. As the results of this study Co-60 has been used with small amount of induced radioactivity in food. PMID:18220055

  1. 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)

  2. An artificial neural network approach to laser-induced breakdown spectroscopy quantitative analysis

    Science.gov (United States)

    D'Andrea, Eleonora; Pagnotta, Stefano; Grifoni, Emanuela; Lorenzetti, Giulia; Legnaioli, Stefano; Palleschi, Vincenzo; Lazzerini, Beatrice

    2014-09-01

    The usual approach to laser-induced breakdown spectroscopy (LIBS) quantitative analysis is based on the use of calibration curves, suitably built using appropriate reference standards. More recently, statistical methods relying on the principles of artificial neural networks (ANN) are increasingly used. However, ANN analysis is often used as a ‘black box’ system and the peculiarities of the LIBS spectra are not exploited fully. An a priori exploration of the raw data contained in the LIBS spectra, carried out by a neural network to learn what are the significant areas of the spectrum to be used for a subsequent neural network delegated to the calibration, is able to throw light upon important information initially unknown, although already contained within the spectrum. This communication will demonstrate that an approach based on neural networks specially taylored for dealing with LIBS spectra would provide a viable, fast and robust method for LIBS quantitative analysis. This would allow the use of a relatively limited number of reference samples for the training of the network, with respect to the current approaches, and provide a fully automatizable approach for the analysis of a large number of samples.

  3. An artificial neural network approach to laser-induced breakdown spectroscopy quantitative analysis

    International Nuclear Information System (INIS)

    The usual approach to laser-induced breakdown spectroscopy (LIBS) quantitative analysis is based on the use of calibration curves, suitably built using appropriate reference standards. More recently, statistical methods relying on the principles of artificial neural networks (ANN) are increasingly used. However, ANN analysis is often used as a ‘black box’ system and the peculiarities of the LIBS spectra are not exploited fully. An a priori exploration of the raw data contained in the LIBS spectra, carried out by a neural network to learn what are the significant areas of the spectrum to be used for a subsequent neural network delegated to the calibration, is able to throw light upon important information initially unknown, although already contained within the spectrum. This communication will demonstrate that an approach based on neural networks specially taylored for dealing with LIBS spectra would provide a viable, fast and robust method for LIBS quantitative analysis. This would allow the use of a relatively limited number of reference samples for the training of the network, with respect to the current approaches, and provide a fully automatizable approach for the analysis of a large number of samples. - Highlights: • A methodological approach to neural network analysis of LIBS spectra is proposed. • The architecture of the network and the number of inputs are optimized. • The method is tested on bronze samples already analyzed using a calibration-free LIBS approach. • The results are validated, compared and discussed

  4. 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

  5. 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

  6. 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.

  7. 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

  8. Artificial radioactivity in the lower Rhone river. Consequences of floods on activity levels and flow toward the mediterranean

    International Nuclear Information System (INIS)

    Despite analytical strategies that today measure ultra-trace levels (i.e., -5 Bq.L-1) of artificial radionuclides, gamma spectrometry of Rhone River samples taken downstream from the nuclear installations located along the Rhone valley regularly detects only 137Cs, 60Co and 241Am. Since dismantlement of the Marcoule-COGEMA reprocessing plant began in 1997, lists of radionuclides in its effluent include 51Cr, 54Mn, 63Ni, 110mAg and 65Zn, released however at levels 10 to 1,000-fold lower than those of 137Cs or 60Co. Today Marcoule effluent is no longer the principal source of 137Cs in the Rhone River basin, as it was in the 1990's. Significant quantities of 137Cs now come from the Rhone watershed itself, from the drainage of soils exposed to atmospheric fallout from the past nuclear tests and from the accident at Chernobyl, and second, from remobilization of previously formed sediment. Our recent research shows that flood events may generate an increase of more than two orders of magnitude in 137Cs activity in downstream Rhone water, because of the input of contaminated particles from both watershed erosion and sediment remobilization. Flood events also generate the flow of high levels of particulate and associated contaminants towards the Mediterranean Sea. Of the 173±22 GBq of 137Cs transferred from the Rhone to the Mediterranean from August 2002 through August 2003, 111±9 GBq went during two floods in September and November 2002: 60% of the annual transfer took place in only 15 days and included almost ten times as much 137Cs activity as is released annually by the reprocessing plant today. The contribution to these flows of re-mobilized Rhone basin sediment inventories contaminated over the past 40 years is under study today. (authors)

  9. Artificial abelian gauge potentials induced by dipole-dipole interactions between Rydberg atoms

    CERN Document Server

    Cesa, A

    2013-01-01

    We analyze the influence of dipole-dipole interactions between Rydberg atoms on the generation of abelian artificial gauge potentials and fields. When two Rydberg atoms are driven by a uniform laser field, we show that the combined atom-atom and atom-field interactions give rise to new, non-uniform, artificial gauge potentials. We identify the mechanism responsible for the emergence of these gauge potentials. Analytical expressions for the latter indicate that the strongest artificial magnetic fields are reached in the regime intermediate between the dipole blockade regime and the regime in which the atoms are sufficiently far apart such that atom-light interaction dominates over atom-atom interactions. We discuss the differences and similarities of artificial gauge fields originating from resonant dipole-dipole and van der Waals interactions. We also give an estimation of experimentally attainable artificial magnetic fields resulting from this mechanism.

  10. 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 or 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

  11. 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

  12. Site selection and investigation for subsurface disposal of radioactive wastes in hydraulically induced fractures

    International Nuclear Information System (INIS)

    Injection into a thick shale formation of intermediate-level radioactive wastes (specific activity of less than 6 x 103 μCi/ml consisting mainly of radionuclides such as strontium and cesium with half-lives of less than 50 years) mixed with cement 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 thus the wastes will remain at depth and in place as long as the injection zone is not subjected to erosion or dissolution. Problems concerning safety of the disposal method are: (1) potential of inducing vertical fractures; (2) phase separation during and after injections; (3) reliability of methods for determining orientation of induced fractures; (4) possibility of triggering earthquakes; and (5) radionuclides leaching and transporting by ground water. Waste injections are made in multiple-layer injection stages in an injection well. After the first series of injections are made at the greatest depth, the well is plugged by cement at the injection depth. The depth of the second series of injections is located at a suitable distance above the first injection depth. The repeated use of the injection well distributes the cost of construction of injection and monitoring wells over many injections, thereby making hydraulic fracturing and grout injection economically attractive as a method for disposal of radioactive wastes. Theoretical considerations of inducing nearly horizontal bedding-plane fractures in shale and field procedures for site selection, safety, monitoring and operation of radioactive waste disposal are discussed. Case histories are used as examples to demonstrate the theoretical applications and field operations

  13. 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.))

  14. High energy proton-induced radioactivity in HgI{sub 2} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Porras, E. [Valencia Univ. (Spain). Dept. Mat. Aplicada y Astronomia; Carter, T. [Southampton Univ. (United Kingdom). Dept. of Physics; Perez, J.M. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Madrid (Spain); Ferrero, J.L. [Instituto de Fisica Corpuscular, Valencia (Spain); Sanchez, F. [Instituto de Fisica Corpuscular, Valencia (Spain); Ruiz, J.A. [Navarra Universidad Publica (Spain). Dept. de Fisica; Schutz, Y. [Grand Accelerateur National d`Ions Lourds (GANIL), 14 - Caen (France); Lei, F. [Southampton Univ. (United Kingdom). Dept. of Physics; Dean, A.J. [Southampton Univ. (United Kingdom). Dept. of Physics; Reglero, V. [Valencia Univ. (Spain). Dept. Mat. Aplicada y Astronomia; Olmos, P. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Madrid (Spain)

    1995-03-15

    Mercuric iodide (HgI{sub 2}) 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 HgI{sub 2} 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.)).

  15. Artificial radioelements

    International Nuclear Information System (INIS)

    This catalogs retails the list of the artificial radioelements obtained at the Zoe reactor. A certain number of methods of concentration and separation has been finalized. The targets are submitted to irradiation in a thermal neutron flux in order to get by neutron reaction the wanted radioelements. In the case of the reaction (n,p), the radioactive element separated chemically in order to produce some radioelements 'without trainer'. For the radioelements obtained from the reaction (n, γ) one uses the effect of Szilard and Chalmers to separate the active and inactive atoms in order to increase the specific activity of the radioelement of interest. (M.B.)

  16. 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

  17. 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.)

  18. Dependence of Characteristics of SURA Induced Artificial ULF/VLF Signals on Geomagnetic Activity

    Science.gov (United States)

    Kotik, D. S.; Ryabov, A. V.; Ermakova, E. N.; Pershin, A. V.

    2015-10-01

    A comprehensive study of artificial ionospheric signal generation in the ULF/VLF bands at SURA facility in Russia was conducted during the past 4 years. We investigated the influence of geomagnetic activity on the characteristics of artificial low-frequency signals under the background of increasing solar activity. No correlation of artificial ULF signals with variations of Earth's magnetic field was observed for weak geomagnetic disturbances (Kp ? 3) while the VLF signals increased in the growth phase of the geomagnetic perturbation. In case of strong magnetic storm (Kp ? 5+) a tendency of the amplitude of the ULF/VLF signals decrease with increasing magnetic disturbance was observed. Sometimes, the modulation of artificial ULF signals with a period of 15-30 s was detected in the decay phase of magnetic storms. During storm time, a change in the polarization of artificial VLF emissions was detected. The right polarization becomes predominant. Interpretation of observed peculiarities of artificial VLF signals is given in the context of the physical mechanism of ionospheric current drive by RF pumping.

  19. Evidences of possible reservoir-induced seismicity by the Pertusillo artificial lake (Southern Italy): preliminary results and ongoing activities

    Science.gov (United States)

    Giocoli, A.; Stabile, T.; Perrone, A.; Piscitelli, S.; Telesca, L.; Lapenna, V.

    2012-12-01

    Reservoir-induced seismicity by filling artificial lakes has been observed over the last 60 years in several regions of the Earth. The presence of water reservoirs in regions with high seismogenic potential, such as the Pertusillo artificial lake in Agri Valley (Southern Italy), can modify the occurrence of earthquakes and influence the seismic hazard of the area. In particular, the Pertusillo lake is a relatively large water reservoir with a capacity of 1.5x108 m3, maintained by a 95 m high concrete dam that was constructed in the Agri river from 1956 to 1962. In this study, we compare the reservoir filling history over the last 30 years with the correspondent spatio-temporal pattern of the observed small to moderate earthquakes (Ml ? 3.2), to interpret possible correlations that could point-out an induced seismicity by the Pertusillo artificial lake. Preliminary results are discussed and ongoing activities in the area of study are presented. This study is funded by the project "Study of the Local Seismicity" at the Val d'Agri Environmental Observatory (Southern Italy), under the agreement between the Basilicata Region and the Italian National Research Council - Institute of Methodologies for Environmental Analysis (CNR-IMAA).

  20. 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)

  1. 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...

  2. 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)

  3. 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...

  4. Radiation dose due to neutron-induced residual radioactivities by the atomic bombs in Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    Radiation dose at 1 m above the ground was estimated due to neutron-induced radioactivities by the atomic bombings in Hiroshima and Nagasaki. The dose rate at the hypocenter at 1 min after the bombing was 600 and 400 cGy h-1 in Hiroshima and Nagasaki, respectively, and rapidly decreased with the decay of the main induced radioactivities of relatively short half-lives: 28Al (2.24 min), 56Mn (2.58 h) and 24Na (15.0 h). The infinite cumulative dose after the bombing was 120 and 57 cGy at the hypocenter of Hiroshima and Nagasaki, respectively, and also sharply decreased with the distance from the hypocenter. Considering the results obtained so far, the people who entered into the area less than 1 km from the hypocenter up to 1 weak after the bombing could receive external dose over 1 cGy from neutron-induced radioactivities. (author)

  5. Characterization of uranium in bituminized radioactive waste drums by self-induced X-ray fluorescence

    International Nuclear Information System (INIS)

    This paper reports the experimental qualification of an original uranium characterization method based on fluorescence X rays induced by the spontaneous gamma emission of bituminized radioactive waste drums. The main 661.7 keV gamma ray following the 137Cs decay produces by Compton scattering in the bituminized matrix an intense photon continuum around 100 keV, i.e. in the uranium X-ray fluorescence region. 'Self-induced' X-rays produced without using an external source allow a quantitative assessment of uranium as 137Cs and uranium are homogeneously mixed and distributed in the bituminized matrix. The paper presents the experimental qualification of the method with real waste drums, showing a detection limit well below 1 kg of uranium in 20 min acquisitions while the usual gamma rays of 235U (185 keV) or 238U (1001 keV of 234mPa in the radioactive decay chain) are not detected. The relative uncertainty on the uranium mass assessed by self-induced X-ray fluorescence (SXRF) is about 50%, with a 95% confidence level, taking into account the correction of photon attenuation in the waste matrix. This last indeed contains high atomic numbers elements like uranium, but also barium, in quantities which are not known for each drum. Attenuation is estimated thanks to the peak-to-Compton ratio to limit the corresponding uncertainty. The SXRF uranium masses measured in the real drums are in good agreement with long gamma-ray spectroscopy measurements (1001 keV peak) or with radiochemical analyses. (authors)

  6. Study of the radioactivity induced in air by a 15-MeV proton beam

    International Nuclear Information System (INIS)

    Radioactivity induced by a 15-MeV proton beam extracted into air was studied at the beam transport line of the 18-MeV cyclotron at the Bern University Hospital (Inselspital). The produced radioactivity was calculated and measured by means of proportional counters located at the main exhaust of the laboratory. These devices were designed for precise assessment of air contamination for radiation protection purposes. The main produced isotopes were 11C, 13N and 14O. Both measurements and calculations correspond to two different irradiation conditions. In the former, protons were allowed to travel for their full range in air. In the latter, they were stopped at the distance of 1.5 m by a beam dump. Radioactivity was measured continuously in the exhausted air starting from 2 min after the end of irradiation. For this reason, the short-lived 14O isotope gave a negligible contribution to the measured activity. Good agreement was found between the measurements and the calculations within the estimated uncertainties. Currents in the range of 120-370 nA were extracted in air for 10-30 s producing activities of 9-22 MBq of 11C and 13N. The total activities for 11C and 13N per beam current and irradiation time for the former and the latter irradiation conditions were measured to be (3.60 ± 0.48)x 10-3 MBq (nA s)-1 and (2.89 ± 0.37)x 10-3 MBq (nA s)-1, respectively (authors)

  7. 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 (Prestorative cycle.

  8. 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...

  9. 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 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

  10. 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

  11. 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.

  12. The effect of radiation-induced free radicals on ion transport through artificial planar lipid membranes

    International Nuclear Information System (INIS)

    The study had the aim to elucidate the influence of free radicals on the function of various ion transport systems, which were built into artificial lipid membranes in planar arrangement. The radicals were obtained using ionising radiation (X-radiation and 14 MeV electrons). Their effects on ion transport were chiefly assessed by stationary conductivity measurements, a kinetic analysis on the basis of the charge-pulse technique was only performed for carrier-mediated ion transport. (orig.)

  13. A subcellular distribution of estrogen receptor-alpha is changed during artificially induced senescence of PC12 pheochromocytoma cells.

    Science.gov (United States)

    Lee, Eunju; Mun, Ga Hee; Oh, Chang Seok; Chung, Yoon Hee; Cha, Choong Lk; Lee, Young Soo; Shin, Dong Hoon

    2004-11-30

    Although estrogen has been considered as a sex hormone for decades, recent reports suggest that estrogen might modulate the development and physiological function of the brain. In addition, the subcellular localization of estrogen receptors (ERs) has shown their presence within both the perinuclear cytoplasm and nuclei, suggesting that these ERs may differ functionally. We, therefore, assayed changes in the subcellular localization of ER-alpha immunoreactivity (IR) in rat pheochromocytoma PC12 cells during the artificial senescence induced by the telomerase inhibitor, 3'-azido-3'-deoxythymidine (AZT). After 2 months of culture with AZT, PC12 cells showed morphological and biochemical characteristics of cellular senescence. In the cells showing artificial senescence, the ER-alpha IR was mainly localized within the cytoplasm, whereas in control cells, ER-alpha IR was found only in the nuclei. Since senescence was induced by AZT, which inhibits the action of telomerase whenever the cells divide, the change in subcellular distribution of ER-alpha IR may be correlated with the length of the telomere. PMID:15531092

  14. Radioactive ion beams produced by neutron-induced fission at ISOLDE

    CERN Document Server

    Catherall, R; Gilardoni, S S; Köster, U

    2003-01-01

    The production rates of neutron-rich fission products for the next-generation radioactive beam facility EURISOL are mainly limited by the maximum amount of power deposited by protons in the target. An alternative approach is to use neutron beams to induce fission in actinide targets. This has the advantage of reducing: the energy deposited by the proton beam in the target; contamination from neutron-deficient isobars that would be produced by spallation; and mechanical stress on the target. At ISOLDE CERN, tests have been made on standard ISOLDE actinide targets using fast neutron bunches produced by bombarding thick, high-Z metal converters with 1 and 1.4 GeV proton pulses. This paper reviews the first applications of converters used at ISOLDE. It highlights the different geometries and the techniques used to compare fission yields produced by the proton beam directly on the target with neutron-induced fission. Results from the six targets already tested, namely UC2/graphite and ThO2 targets with tungsten an...

  15. 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...

  16. 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)

  17. 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.

  18. Prediction of Irradiation induced hardening by Artificial Neural Network for 304 and 316 stainless steels

    International Nuclear Information System (INIS)

    The internal structures of pressurized water reactors (PWR) located close to the reactor core are used to support the fuel assemblies, to maintain the alignment between assemblies and the control bars and to canalize the primary water. In general these internal structures consist of baffle plates in a solution annealed (SA) 304 stainless steel and baffle bolts in a cold worked (CW) 316 stainless steel. These components undergo a large neutron flux at temperatures between 280 and 380 .deg. C. As a result, the materials exhibit a substantial increase in yield stress and a reduction in ductility which may deteriorate the performance of a reactor operation. For instance the observed cracks in bolts, usually attributed to irradiation assisted stress corrosion cracking (IASCC). In this work, we tried to apply a artificial neural network (ANN) approach to a prediction of a IASCC of an austenitic stainless steels SA 304 and CW 316. We have predicted the yield stress in terms of a dislocation loops size and density. Besides, we compared experimental data with prediction data by an artificial neural network

  19. 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)

  20. Artificial granularity in two-dimensional arrays of nanodots fabricated by focused-electron-beam-induced deposition

    International Nuclear Information System (INIS)

    We have prepared 2D arrays of nanodots embedded in an insulating matrix by means of focused-electron-beam-induced deposition using the W(CO)6 precursor. By varying the deposition parameters, i.e. the electron beam current and energy and the raster constant, we obtain an artificial granular material with tunable electrical properties. The analysis of the temperature dependence of the conductivity and of the current-voltage characteristic suggests that the transport mechanism is governed by electron tunneling between artificial grains. In order to understand the nature of the granularity and thus the microstructural origin of the electronic transport behavior, we perform TEM and micro-Raman investigations. Independent of the deposition parameters, TEM measurements show that the dots are constituted of amorphous tungsten carbide clusters embedded in an amorphous carbonaceous matrix. Micro-Raman spectra show two peaks, around 690 and 860 cm-1 associated with the W-C stretching modes. Higher frequency peaks give information on the composition of the matrix. In particular, we measure a peak at about 1290 cm-1, which is associated with sp3 carbon bonds. Furthermore we detect the so-called D and G peaks, at about 1350 and 1560 cm-1, associated with the vibration modes of the sp2 carbon bonds. The analysis of the position of the peaks and of their relative intensity suggests that the composition of the matrix is between nanocrystalline graphite and amorphous carbon.

  1. Artificial neural network model of the strength of thin rectangular plates with weld induced initial imperfections

    International Nuclear Information System (INIS)

    Probabilistic assessment of post-buckling strength of thin plate is a difficult problem because of computational effort needed to evaluate single collapse load. The difficulties arise from the nonlinear behaviour of an in-plane loaded plate showing up multiple equilibrium states with possible bifurcations, snap-through or smooth transitions of states. The plate strength depends heavily on the shape of geometrical imperfection of the plate mid-surface. In this paper, an artificial neural network (ANN) is employed to approximate the collapse strength of plates as a function of the geometrical imperfections. For the training set, mainly theoretical imperfections with the corresponding collapse loads of plate calculated by FEM are considered. The ANN validation is based on the measured imperfections of ship plating and FEM strength.

  2. 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

  3. Artificial neural network model of the strength of thin rectangular plates with weld induced initial imperfections

    Energy Technology Data Exchange (ETDEWEB)

    Sadovsky, Z., E-mail: usarzsad@savba.s [USTARCH SAV, Institute of Construction and Architecture, Slovak Academy of Sciences, 845 03 Bratislava (Slovakia); Guedes Soares, C. [Centre for Marine Technology and Engineering, Technical University of Lisbon, Instituto Superior Tecnico, 1049-001 Lisboa (Portugal)

    2011-06-15

    Probabilistic assessment of post-buckling strength of thin plate is a difficult problem because of computational effort needed to evaluate single collapse load. The difficulties arise from the nonlinear behaviour of an in-plane loaded plate showing up multiple equilibrium states with possible bifurcations, snap-through or smooth transitions of states. The plate strength depends heavily on the shape of geometrical imperfection of the plate mid-surface. In this paper, an artificial neural network (ANN) is employed to approximate the collapse strength of plates as a function of the geometrical imperfections. For the training set, mainly theoretical imperfections with the corresponding collapse loads of plate calculated by FEM are considered. The ANN validation is based on the measured imperfections of ship plating and FEM strength.

  4. Artificial radionuclide concentrations in the Bulgarian population over the period 1986-1988: An assessment of the irradiation of the Bulgarian population as a result of the global radioactive contamination of the country after 1 May 1986

    International Nuclear Information System (INIS)

    During the time of radioactive contamination of the Bulgarian territory due to the Chernobyl accident after 1 May 1986 groups of the population were examined for determination of artificial radionuclide concentrations in the body. From 1 May to 15 June tests were done on about 6000 people, both male and female, of different ages and from different regions of the country to measure the concentrations of 131I in the thyroid glands. The highest concentrations were observed in the period 20-30 May. The highest mean values were observed to be about 300 Bq, although in some people levels of the order of 6000 Bq were detected. Between 1986 and 1988 about 4000 people were examined for artificial radionuclides with fixed and portable whole body counters. During May-July 1986 about 15 artificial radionuclides were found. After the summer of 1986 mainly 137Cs and 134Cs were detected. Their concentrations gradually increased and reached a maximum in April 1987 for 137Cs and in January 1987 for 134Cs. Then they gradually decreased. It was found that the concentrations of both radionuclides in the body depend on the age, sex, physiological characteristics and diet of the individual and on their concentration in food, which was quite different for the different regions of the country. The highest concentrations were detected in people living in southern Bulgaria - these reached 300 Bq/kg (total for 134Cs and 137Cs). (author). 4 figs, 1 tab

  5. 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.

  6. 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...

  7. 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)

  8. Leaching of artificial radionuclide out of minerals

    International Nuclear Information System (INIS)

    Leaching of radionuclides induced by neutron bombardment in natural silicates and silicophosphate of rare earth elements and calcium, is studied using gamma-spectrometry. It is shown that solution of minerals under the effect of artificial subsoil water at 75 deg C is incongruent character: difference in leaching of cobalt and actinides reaches value equal to two magnitudes. Behaviour of lanthanides as analogs of transplutonium elements is of special interest. Essential role of specimen microphase composition is pointed out. The suggested methodological approach is efficient at selection of matricies for fixaton of radioactive wastes

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

    OpenAIRE

    He, Lijuan; Li, Yuxiong; 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 r...

  10. Processes of radiation-induced defect formation in quartz. III. Artificial amethyst

    International Nuclear Information System (INIS)

    It is shown that during gamma irradiation of r-crystals of amethyst in the dose range 104-106 R there are processes of migration of electron-alkali ion pairs (e-, Me+) and e-, H+ from O- Me+ and O-H+ groups of structural defects to triply coordinate Si? ions near interstitial iron ions. These processes create the necessary conditions for occurrence in the dose range 3 x 105-107 R of processes of countermigration of Me+ and H+ ions. With irradiation of amethyst by doses of over 106 R, the formation of marked concentrations of broken Si-O bonds causes the processes of migration of pairs e-, Me+ from growth defects to these radiation traps. The proposed model of radiation-stimulated processes explains the kinetics of the change in the main parameters of the optical absorption spectra in the UV, visible, and IR regions, acoustic (f = 1 MHz) and dielectric (f = 1 kHz) losses of artificial amethyst under gamma irradiation

  11. Radioactivity-induced modifications in the weight of the thyroid gland of the New Zealand adult rabbit

    Energy Technology Data Exchange (ETDEWEB)

    Alcaraz, M.; Genoves, J.L.; Berna, J.D.; Meseguer, J.; Garcia-Ayala, A.

    1988-01-01

    The radioactivity-induced modifications in the weight of the thyroid gland of the New Zealand adult rabbit, as well as the radioactivity-induced ultrastructural changes underwent by these glands were studied. In order to achieve this, three groups, each of 36 animals, were established: One group regarded as erythroid, another of animal treated with propylthiouracil (PTU), and a third group treated with protirelin (TRH). The animals belonging to each group were distributed in six lots according to the total dose of radiation administered to their thyroid glands: 0 Gy (non-radiated group), 4 Gy, 8 Gy, 12 Gy, 12 Gy, 16 Gy and 20 Gy. The results obtained showed that the isolated use of thyroid gland weight as a biological parameter is not a specific indicator of the degree of radiosensitivity, nor of the status of functional glandular activity. The structural changes induced by radioactivity occurred earlier and were more intense in the group treated with protirelin (TRH) which was considered as hyperfunctioning.

  12. Radioactivity-induced, modifications in the weight of the thyroid gland of the New Zeland adult rabbit

    International Nuclear Information System (INIS)

    The radioactivity-induced modifications in the weight of the thyroid gland of the New Zealand adult rabbit, as well as the radioactivity-induced ultrastructural changes underwent by these glands were studied. In order to achieve this, three groups, each of 36 animals, were established: One group regarded as euthyroid, another of animal treated with propylthiouracil (PTU), and a thrid group treated with protirelin (TRH). The animals belonging to each group were distributed in six lots according to the total dosis of radiation administered to their thyroid glands: 0 Gy (non-radiated group), 4 Gy, 8 Gy, 12 Gy, 16 Gy and 20 Gy. The results obtained showed that the isolated use of thyroid gland weight as a biological parameters is not a specific indicator of the dregee of radiosensitivity, nor of the status of functional glandular activity. The structural changes induced by radioactivity occurred earlier and were more intense in the group treated with protirelin (TRH) which was considered as hyperfunctioning. (Author)

  13. Evaluation of a risk communication approach for maintenance staff working with induced radioactivity in medical linear accelerators

    International Nuclear Information System (INIS)

    In order to promote consensus building on decommissioning operation rules for medical linear accelerators in Japan, we carried out a risk communication (RC) approach mainly providing knowledge for maintenance staff regarding induced radioactivity. In February 2012, we created a booklet (26 pages) to present an overview of the amended law, the mechanism and the distribution of induced radioactivity showing the actual radiation dose rate around a linear accelerator and actual exposure doses to staff. In addition, we co-sponsored a seminar for workers in this field organized by the Japan Medical Imaging and Radiological Systems Industries Association to explain the contents of this booklet, and answer questions regarding induced radioactivity of linear accelerators as an RC program. As a result, the understanding of staff regarding the regulations on maximum X-ray energy on linear accelerators (P<0.05), and the outline of clearance systems (P<0.01), were facilitated by RC. In addition, we found that about 70% of maintenance staff considered that the cooling time for decommissioning operation depended on the situation. Our RC approach suggests that consensus building should be used to make rules on decommissioning operations for linear medical accelerators. (author)

  14. 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.

  15. 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

  16. 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

  17. 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)

  18. 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)

  19. 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

  20. 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...

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

    Energy Technology Data Exchange (ETDEWEB)

    Li Heng [Key Laboratory of Photochemistry, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China); Yang Shuzhen [Key Laboratory of Photochemistry, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China); Xie Jie [Key Laboratory of Photochemistry, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China); Zhao Jingquan [Key Laboratory of Photochemistry, Center for Molecular Science, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080 (China)]. E-mail: zhaojq@iccas.ac.cn

    2007-01-15

    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 L{sub CM} 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 L{sub CM} with the membrane but weaken the electrostatic interaction of linker polypeptides to C-PC and/or APC.

  2. 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

  3. 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...

  4. 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

  5. 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.

  6. Early age sealing of buffer-rock gap by artificial wetting to induce bentonite swelling

    International Nuclear Information System (INIS)

    Document available in extended abstract form only. The aim of this work is to study the homogeneous and rapid swelling of bentonite in the gap between the buffer blocks and the rock wall of the Olkiluoto disposal facility by artificial wetting. The focus was on the construction period of the deposition hole and buffer, and thus only the very early ages of the first weeks. In practice it is desirable that the bentonite material has a volume increase sufficient enough to prevent rock scaling while lowering the risks of bentonite piping and erosion due to potential water flow. This initial study was done in a small-scale mock-up in laboratory conditions. The small-scale steel mock-up had dimensions of 39 cm in height by 36 cm in diameter and included 12 pressure sensors, two displacement transducers, thermal couples, and pore water pressure measurements. The radial and axial pressure development was typically measured over a two week period to assess the rate and magnitude of sealing. A steel confining lid was used for simulating overpressure, though in some cases a plexiglass lid was used to take video images of the gap sealing. The buffer blocks were produced by isostatic compression of 100 MPa. The material was MX-80 Wyoming bentonite having a water content of approximately 13% and a dry density of 1890 kg/m3. The testing samples were dry sawn and core drilled from the large block and machined to their final dimensions. These were typically 30 x 30 cm, either as a solid block or three disks of 10 cm height each. The diameter was sometimes varied to allow for a change of gap width between 25 to 50 mm The study included various scenarios, such as: eccentric aligned blocks with gap sizes of 5 and 45 mm, free upward swelling or confinement, different types of pellet and granular gap filling, addition of water at varying rates, and longer term test duration. The samples were typically disassembled after two weeks. At this ending point, material assessments were done to quantify the variation of water content, SHORE hardness and density across the buffer and gap filling. The results showed that the bentonite buffer exposed to rapid artificial wetting is able to uniformly swelling to fill the gap within the first day with 25 mm gap. When only a water-filled gap was used, a radial pressure of about 200 kPa was achieved within the first few days with gas-tight steel lid in use. The pressure reached a maximum after about 2 weeks and then gradually declined due to moisture distribution from the gap towards the centre of the buffer block. Radial cracks appeared within the blocks within the test duration, which extended the full depth and across blocks. These could tighten and seal with prolonged testing or water addition. When gap filling materials were used, such as Cebogel pellets or Ibeco Seal granules, the radial pressure had maximum values up to 600 kPa. The pressure developed at a much faster rate and was better maintained over time, without the same type of pressure drop experienced with only an air-water filled gap. It was demonstrated that water could percolate through the pellet filling to be evenly distributed within a few minutes. This was also achieved in longer tube-filling tests simulating actual deposition holes, showing that when the pellets were placed by free-falling there was enough void space to allow full water filtration. The swollen material was well confined in the gap when an axial confining pressure was used from the start of testing. In some cases, the vertical, or axial, uplift pressure due to swelling was as much as double the radial pressure. Yet this could theoretically be counter-balanced by applying a confining load or lid to prevent buffer uplift into the tunnel backfill area. These post-test assessments showed that moisture equilibrium between the gap and buffer was not reached within the short test duration as expected. The outer gap filled material could have water contents on the order of 100 to 400% of the buffer. The area near the top of the sample often had a higher water content, attributed

  7. A comparative study of laser induced breakdown spectroscopy analysis for element concentrations in aluminum alloy using artificial neural networks and calibration methods

    International Nuclear Information System (INIS)

    A comparative study of analysis methods (traditional calibration method and artificial neural networks (ANN) prediction method) for laser induced breakdown spectroscopy (LIBS) data of different Al alloy samples was performed. In the calibration method, the intensity of the analyte lines obtained from different samples are plotted against their concentration to form calibration curves for different elements from which the concentrations of unknown elements were deduced by comparing its LIBS signal with the calibration curves. Using ANN, an artificial neural network model is trained with a set of input data of known composition samples. The trained neural network is then used to predict the elemental concentration from the test spectra. The present results reveal that artificial neural networks are capable of predicting values better than traditional method in most cases

  8. Radioactive contamination of the biosphere

    International Nuclear Information System (INIS)

    The present volume deals with the main aspects of radioactive contamination of the biosphere. Cosmic radiation, natural sources of ionizing radiation, artificial radionuclides, radioactive fallout, radioactive wastes and connected problems are treated as well as the radioactivity and its interaction with the atmosphere, hydrosphere, soil and plant, animal and human organism. Problems of somatic and genetic radiation effects and of radiation protection are discussed finally

  9. 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.

  10. 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

  11. Diagnostic accuracy of artificially induced vertical root fractures: a comparison of direct digital periapical images with conventional periapical images

    International Nuclear Information System (INIS)

    To compare the diagnostic accuracy for the detection of root fractures in CMOS-based digital periapical images with conventional film-based periapical images. Sixty extracted single-root human teeth with closed apices were prepared endodontically and divided into two groups; artificially induced vertical root fracture group and control group. All radiographs were obtained using the paralleling technique. The radiographs were examined by 4 observers three times within a 4 week interval. Receiver operating characteristic (ROC) analysis was carried out using data obtained from four observers. Intra- and inter-examiner agreements were computed using kappa analysis. The area under the ROC curve (Az) was used as an indicator of the diagnostic accuracy of the imaging system. Az values were as follows: direct-digital images; 0.93, film-based images; 0.92, and inverted digital images; 0.91. There was no significant difference between imaging modalities(P<0.05). The kappa value of inter-observer agreement was 0.42(range:0.28-0.60) and intra-observer agreement was 0.57(range:0.44-0.75). There is no statistical difference in diagnostic accuracy for the detection of vertical root fractures between digital periapical images and conventional periapical images. The results indicate that the CMOS sensor is a good image detector for the evaluation of vertical root fractures.

  12. 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.

  13. 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

  14. 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)

  15. 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.

  16. 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

  17. Induced radioactivity in the blood of cancer patients following Boron Neutron Capture Therapy

    OpenAIRE

    Fujiwara, Keiko; Kinashi, Yuko; TAKAHASHI, TOMOYUKI; Yashima, Hiroshi; Kurihara, Kouta; Sakurai, Yoshinori; TANAKA, HIROKI; ONO, Koji; Takahashi, Sentaro

    2013-01-01

    Since 1990, Boron Neutron Capture Therapy (BNCT) has been used for over 400 cancer patients at the Kyoto University Research Reactor Institute (KURRI). After BNCT, the patients are radioactive and their 24Na and 38Cl levels can be detected via a Na-I scintillation counter. This activity is predominantly due to 24Na, which has a half-life of 14.96 h and thus remains in the body for extended time periods. Radioactive 24Na is mainly generated from 23Na in the target tissue that is exposed to the...

  18. 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 ...

  19. 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.

  20. 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

  1. 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

  2. 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)

  3. Residual neutron-induced radioactivities of Co-60 and Eu-152 in rocks exposed to Nagasaki Atomic Bomb

    International Nuclear Information System (INIS)

    Radioactivities of residual neutron-induced radionuclides of Co-60 and Eu-152 in rocks exposed by Nagasaki Atomic Bomb were determined. Samples were obtained from the surface to 2 cm in depth of rocks. Each sample was pulverized and placed in a plastic container, and gamma-ray spectrum was measured with a pure germanium semiconductor detector. To determine the amount of natural element of cobalt and europium contained in each sample, the neutron activation method was performed by the reactor of the Research Reactor Institute, Kyoto University (KUR). The radioactivities of Co-60 and Eu-152 were evaluated as per 1 mg natural element at the time of Atomic Bomb. The results show that the radioactivities of Co-60 and Eu-152 in rocks were decreased with increasing slant distance. The Co-60 activity was 6.88±2.13 Bq/mgCo and the Eu-152 activity was 75.9±8.79 Bq/mgEu at 510 m from the epicenter. When we compared the activity of Eu-152 calculated by Loewe with our data, we found a divergence between them as the distance from the epicenter increases. (author)

  4. 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

  5. Induced radioactivity in the blood of cancer patients following Boron Neutron Capture Therapy

    International Nuclear Information System (INIS)

    Since 1990, Boron Neutron Capture Therapy (BNCT) has been used for over 400 cancer patients at the Kyoto University Research Reactor Institute (KURRI). After BNCT, the patients are radioactive and their 24Na and 38Cl levels can be detected via a Na-I scintillation counter. This activity is predominantly due to 24Na, which has a half-life of 14.96 h and thus remains in the body for extended time periods. Radioactive 24Na is mainly generated from 23Na in the target tissue that is exposed to the neutron beam in BNCT. The purpose of this study is to evaluate the relationship between the radioactivity of blood 24Na following BNCT and the absorbed gamma ray dose in the irradiated field. To assess blood 24Na, 1 ml of peripheral blood was collected from 30 patients immediately after the exposure, and the radioactivity of blood 24Na was determined using a germanium counter. The activity of 24Na in the blood correlated with the absorbed gamma ray doses in the irradiated field. For the same absorbed gamma ray dose in the irradiated field, the activity of blood 24Na was higher in patients with neck or lung tumors than in patients with brain or skin tumors. The reasons for these findings are not readily apparent, but the difference in the blood volume and the ratio of bone to soft tissue in the irradiated field, as well as the dose that leaked through the clinical collimator, may be responsible. (author)

  6. A quantitative analysis of microbially-induced calcite precipitation employing artificial and naturally-occurring sediments

    Science.gov (United States)

    Lokier, Stephen; Krieg Dosier, Ginger

    2013-04-01

    Microbially-induced calcite precipitation is a strong candidate for the production of sustainable construction materials. The process employs the microbe Sporosarcina pasteurii as an agent to microbially mediate the precipitation of calcium carbonate to bind unconsolidated sediment. As this process can be achieved under ambient temperature conditions and can utilise a wide variety of easily-available sediments, potentially including waste materials, it is envisioned that this procedure could significantly reduce carbon-dioxide emissions in the construction industry. This study describes and quantifies the precipitation of calcite cement in a range of naturally-occurring sediments compared with a control matrix. The study establishes the optimum treatment time for effective cement precipitation in order to produce a material that meets the standards required for construction whilst keeping economic and environmental outlays at a minimum. The 'control sediment' employed industrial-grade glass beads with a grain size range of 595-1180 microns (16-30 US mesh). Sporosarcina pasteurii were mixed in a solution of urea and calcium chloride and then inoculated into the control sediment. The microbes attach to the surface of the sediment grains and employ urea as a source of energy to produce ammonia and carbon dioxide. By so doing, they increase the pH of the solution allowing calcium carbonate to precipitate at the cell walls to act as nucleation points facilitating the precipitation of cements as a grain-coating and biocementing the unconsolidated sediment. The solution treatment was repeated at eight hour intervals with samples removed for detailed analysis after each every five consecutive treatments (i.e. 40 hours). The process was repeated to produce 20 samples with treatment times between 40 and 800 hours. Cemented samples were impregnated with blue epoxy and examined petrographically to monitor cement development. Modal analysis was undertaken on each cemented sample to establish the abundance and natures of precipitated cements. Samples were also examined via SEM to monitor cement distribution and quantify the thickness of cements on grain surfaces and at grain-on-grain contacts. Analysis established that precipitation of calcite continues until 400 hours (50 treatments) after which time there is only an insignificant precipitation of new calcite cement. This is inferred to result from the occlusion of porosity (from 40% to 10%) and observed calcite precipitation at grain-on-grain contacts, both factors reduce the permeability of the samples and, thus, inhibit the flow of solution through the medium. The precipitated calcite cement was found to be dominantly grain-rimming with a consistent thickness averaging 11 microns. A range of naturally-occurring sediments were collected from surface locations throughout the United Arab Emirates. Samples were submitted to a range of petrographic and geochemical analysis in order to quantify grain-size distribution, grain composition and bulk total carbonate content (7.5-94 wt%). Sub-samples of these sediments were established by sieving and the cementation potential of different size fractions was established. Following treatment, these samples were submitted to the same analysis as those employed for the control sediment. A relationship between both sediment grain-size characteristics and sediment grain composition to cement precipitation was established and is discussed.

  7. 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

  8. 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

  9. 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

  10. 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)

  11. Measurement of induced radioactivities for the evaluation of internal exposure at high energy accelerator facilities

    International Nuclear Information System (INIS)

    At high-intense and high energy accelerator facilities, accelerator components are exposed to primary and/or secondary high energy particles during machine operation. As a result, these become radioactive and the radioactivities are accumulated with operation time. When workers engage in maintenance work such as cutting, welding, etc. in the areas with residual activities. These become a source of internal exposure through the inhalation of radioactive airbornes as well as a source of external exposure. The estimation of external doses to workers is relatively easy by directly measuring the radiation fields by pertinent radiation counters. While the internal dose depends very much on the kinds of radioactive nuclides and their concentrations in air. In a routine survey for internal dose evaluation, airborne activities are filtered and their activities on the filter are measured with a GM counter with an automatic sample changer at KEK (the High Energy Accelerator Research Organization). Ordinarily many filter samples have to be measured with a relatively short counting time, so this gross beta counting is a practical way in a routine procedure. In order to evaluate the internal dose from these countings, it is necessary to examine precisely the kinds of radioactivities and their concentrations collected on the filters by a Ge semiconductor detector, and the correlation between the gross beta counting and the actual dose has to be made clear in advance. However, kinds of radioactivities and their concentrations depend very much on production rates of individual nuclides and time variations after beam-off. First, in order to elucidate the production rates of individual nuclides and their concentrations after beam-off, metal samples of Al, Fe, Cu, Steel, etc., which are principal materials used in accelerator facilities, were irradiated at various places in the tunnel of KEK-500MeV and 12GeV proton synchrotrons. By using these irradiated samples, we examined extensively a GM gross counting method for evaluation of internal doses and compared it with a Ge counting method under various conditions. The application, of this gross beta counting method to actual situations at high energy accelerator facilities is discussed. Further, Fe-55 is abundantly produced in accelerator components, however both above methods can not be applicable to the estimation of internal doses due to this isotope because Fe-55 decays through EC process with low energy X-rays and no gamma-ray. A low energy photon spectroscopy (LEPS) using a Ge-semiconductor was applied to the measurement of Fe-55 in activated components. In routine work, it is very convenient if the radioactivity of Fe-55 can be deduced from the concentrations of other long-lived isotopes such as Mn-54, Cr-51, concomitantly present in those irradiated materials. We examined extensively the possibility of direct evaluation of Fe-55 internal doses. (author)

  12. Numerical Simulation and Artificial Neural Network Modeling for Predicting Welding-Induced Distortion in Butt-Welded 304L Stainless Steel Plates

    Science.gov (United States)

    Narayanareddy, V. V.; Chandrasekhar, N.; Vasudevan, M.; Muthukumaran, S.; Vasantharaja, P.

    2016-02-01

    In the present study, artificial neural network modeling has been employed for predicting welding-induced angular distortions in autogenous butt-welded 304L stainless steel plates. The input data for the neural network have been obtained from a series of three-dimensional finite element simulations of TIG welding for a wide range of plate dimensions. Thermo-elasto-plastic analysis was carried out for 304L stainless steel plates during autogenous TIG welding employing double ellipsoidal heat source. The simulated thermal cycles were validated by measuring thermal cycles using thermocouples at predetermined positions, and the simulated distortion values were validated by measuring distortion using vertical height gauge for three cases. There was a good agreement between the model predictions and the measured values. Then, a multilayer feed-forward back propagation neural network has been developed using the numerically simulated data. Artificial neural network model developed in the present study predicted the angular distortion accurately.

  13. 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%

  14. 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

  15. 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)

  16. Ambient radioactivity levels and radiation doses. Annual report 2012

    International Nuclear Information System (INIS)

    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.

  17. 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)

  18. 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

  19. 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)

  20. 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…

  1. 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

  2. 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.

  3. 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.

  4. THE INTEGRAL ESTIMATION OF PERCEIVED DISCOMFORT CONDITION OF THE URANIUM PROCESSING ENTERPRISE EMPLOYEES AND CITY RESIDENTS WITH ARTIFICIALLY INCREASED NATURAL SOURCE OF RADIOACTIVITY

    Directory of Open Access Journals (Sweden)

    Shevchenko ?. A.

    2014-03-01

    Full Text Available Introduction. After the Chernobyl accident radio-anxiety of the population remains one of the most acute psychosocial problems in Ukraine, especially in the regions where uranium is extracted and processed. Uranium raw material – basis of nuclear fuel for nuclear energy – has been processed in Zhovti Vody of Dnipropetrovsk region since 1950s. Zhovti Vody is a unique place. The city is surrounded with the uranium production facilities: the hydrometallurgical factory and the uranium waste tailing damp. Purpose. Our aim was to estimate perceived health status of Zhovti Vody citizens (population category «?» and the employees of the industrial complex «Eastern Mining Processing Plant» (MPP, who work with radiation sources daily (categories «A» and «B». Materials and Methods. We checked the health status of average Zhovti Vody citizens (102 and industrial complex employees (104, who work with radiation sources daily. The samplings deferred only by the place of employment of respondents. The average age of respondents (M ± m was 41.6 ± 0.9 years. The gender (? > 0.9 and age (? > 0.7 characteristics were similar for both groups. The applied research methods were developed and tested by the specialists of V. M. Bekhterev Psychoneurological Research Institute (Saint Petersburg. Discussion 1. According to the integral estimation of the perceived discomfort condition: the employees complained less of pain, but citizens who did not work in the industrial complex complained more. 2. Mental health of the population corresponds to the low (by anxiety and frustration indices and middle assessment levels (on the constriction and aggressiveness scales. However, the employees of the industrial complex showed the lower degree of symptom expression. 3. The majority of population (88.3 % showed the low level of social frustration regardless to the place of employment. 4. The correlation between physical and mental health statuses (anxiety, constriction, psychological and social frustration confirmed interaction between pain and psychological symptoms. The employees of the industrial complex showed better estimation of perceived health status comparing with citizens, who work in other institutions. Thus, the employees of any industrial complexes normally express less radio-anxiety, because they work with radioactive sources daily.

  5. Radioactive waste disposal in granite

    International Nuclear Information System (INIS)

    Within the framework of completing its knowledge of various rock formations, the Federal Government also considers the suitability of granite for radioactive waste disposal. For this purpose, the Federal Minister of Research and Technology participated from 1983 to 1990 in relevant research and development activities in the NAGRA rock laboratory at Grimsel, Switzerland. After about 17 field tests, it can be stated that the understanding of basic connections and interactions between the mechanical behaviour of the rock, which is determined, for instance, by natural or artificially induced rock movements, and the hydrogeological or rock hydraulic relations could be clearly improved. So far, the German share in the project costs amounts to a total of approximately DM 20.7 million. Till the end of 1993, further activities are scheduled to be carried out which will require financial funds of about DM 6.3 million. (orig./HSCH)

  6. Domain wall resistance between artificial domains created in exchange coupled bilayers by keV He ion bombardment induced magnetic patterning

    International Nuclear Information System (INIS)

    Ion bombardment induced lateral magnetic patterning (IBMP) has been used to generate different magnetic patterns (artificial domains) in an exchange bias bilayer system without changes in the surface topography. This technique enables to create adjacent areas with designed magnetization directions stable in remanence. Within the same layer system it is possible to create Bloch or Neel walls. Corresponding magnetical stripe patterns were analyzed by magnetic force microscopy and Kerr microscopy. Magnetoresistance measurements were performed to investigate the domain wall resistance (DWR) at room temperature and low temperatures.

  7. 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.

  8. Prospective study in the management of high-dose radioactive iodine therapy induced gastritis

    International Nuclear Information System (INIS)

    Full text: Gastritis is simply defined as inflammation of the gastric mucosa. In post-RAI patients, this is one of the most common complications that are encountered. Some patients may even require repetitive administration of high doses of radioactive iodine (I-131). Small doses of radiation (up to 1500 R) cause reversible mucosal damage, whereas higher radiation doses cause irreversible damage with atrophy and ischemic-related ulceration. Reversible changes consist of degenerative changes in epithelial cells and nonspecific chronic inflammatory infiltrate in the lamina propria. Higher amounts of radiation cause permanent mucosal damage, with atrophy of fundic glands, mucosal erosions, and capillary hemorrhage. Associated submucosal endarteritis results in mucosal ischemia and secondary ulcer development. Recurrent gastritis, if left untreated, may be a predisposing factor for gastric malignancy. Methods:A total of thirty post-RAI subjects were evaluated for signs and symptoms of gastritis and were divided into 3 groups which were given drugs for gastritis (H2-receptor antagonist, proton pump inhibitor, and sucralfate). Survey forms were distributed to evaluate the presence of nausea, vomiting, epigastric pain (graded according to severity of pain), and gastrointestinal bleeding. Results were tallied accordingly. Results and Discussion: In a total of 3 subjects who were given sucralfate, all of them did not experience any nausea and vomiting. One subject experienced mild epigastric discomfort and another subject was able to experience a non-specific symptom of abdominal bloatedness. (Note: Subjects are still for completion) In theory, radiation irritates the mucosa causing inflammation and mucosal damage which is further irritated by gastric acid secretion. The administration of H2-receptor blockers and proton pump inhibitors only inhibit gastric acid secretion while existing inflammation of mucosa due to high doses of radiation is left untreated. However, sucralfate may selectively bind to the damaged mucosa and act as a barrier to acid, pepsin and bile. Conclusion: Promising results are noted, however, completion of subjects is still warranted to further strengthen the study. Aside from being the most common complication of high dose and repetitive radioactive iodine administration, management of gastritis in post-RAI patients is valuable because of the possible sequelae of gastrointestinal bleeding and/or gastric malignancy. (author)

  9. 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.

  10. 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.

  11. Benchmark studies of induced radioactivity produced in LHC materials, part I: Specific activities

    International Nuclear Information System (INIS)

    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 analysed 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. (authors)

  12. Induced polarisation and the assessment of sorption/diffusion at radioactive waste repository sites

    International Nuclear Information System (INIS)

    Induced polarisation is a geophysical technique used in mineral exploration in search of metallic ore deposits. Clay minerals also polarise when subjected to an electric current, although the mechanism differs from that of metallic bodies, and involves, amongst other properties, the clay mineral species, the interlayer spacing of the clay, and the nature and abundance of mobile ions in the pore fluid. As a result, it was proposed that induced polarisation of clays could be used as a method for determining their permeability and diffusivity. The work carried out in developing experimental procedures, and evaluating the feasibility of the proposal is presented in this report. (author)

  13. 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

  14. Ablation from artificial or laser-induced crater surfaces of silver by laser irradiation at 355 nm

    DEFF Research Database (Denmark)

    Toftmann, B.; Schou, Jørgen; Larsen, N.B.

    The angular distribution of laser ablated particles from silver irradiated at 355 nm has been studied. The angular distribution from craters prepared by more than 10(4) shots exhibits only minor changes compared with that from a nonirradiated target. The distribution from artificial cylindrical c...... craters of a depth comparable to the laser spot dimensions is about one order of magnitude smaller at large exit angles than that from a flat target....

  15. 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...

  16. 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 humans. RECENT FINDINGS: Short-term intervention studies have shown divergent results wrt appetite...... regulation, but overall artificial sweeteners cannot be claimed to affect hunger. Data from longer term intervention studies are scarce, but together they point toward a beneficial effect of artificial sweeteners on energy intake, body weight, liver fat, fasting and postprandial glycemia, insulinemia, and...

  17. 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...

  18. 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

  19. 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.

  20. Natural - synthetic - artificial!

    DEFF Research Database (Denmark)

    Nielsen, Peter E

    2010-01-01

    The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life.......The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life....

  1. 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.

  2. 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)

  3. 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)

  4. 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)

  5. Induced radioactivity of materials by stray radiation fields at an electron accelerator

    International Nuclear Information System (INIS)

    Samples of soil, water, aluminum, copper and iron were irradiated in the stray radiation field generated by the interaction of a 28.5 GeV electron beam in a copper-dump in the Beam Dump East facility at the Stanford Linear Accelerator Center. The specific activity induced in the samples was measured by gamma spectroscopy and other techniques. In addition, the isotope production in the samples was calculated with detailed Monte Carlo simulations using the FLUKA code. The calculated activities are compared to the experimental values and differences are discussed

  6. Effect of radiation-induced defects on the probability of switching-on of artificial microplasmas in silicon

    International Nuclear Information System (INIS)

    The result of experimental investigation of radiation defect influence on one of the main microplasma parameters characterizing breakdown instability, probability of inclusion into time unit P01 are presented. The diameter of artificial microplasma, determined according to recombination radiation, is 3-4 ?m. Microplasma break-down voltage is Uc?8V. Radiation defects are introduced using radiation of high-energy electrons (E=3.8 MeV). Electron flux intensity is ? 1.9x1010cm-2xC-1, radiaiton dose ?=1013-1017 cm-2. Pulse methods are used to determine parameter P01

  7. Artificial Blood

    Directory of Open Access Journals (Sweden)

    Umit Yasar

    2012-04-01

    Full Text Available The problems and additional cost factor involved in collecting and storing human blood, as well as the pending worldwide shortages are the main driving forces in the development of blood substitutes. Studies on artificial blood basically aim to develop oxygen carrying compounds, produce stem cell-based erythrocyte cells in vitro and, implement the functions and movements of natural hemoglobin molecules found in erythrocyte cells through artificial erythrocyte cells. Consequently, major areas of research in artificial blood studies are haemoglobin-based oxygen carriers, perfluorochemicals, respirocytes and stem cells. Even though these artificial erythrocyte cells do not qualify as perfect red blood cell substitutes yet, they have many potential clinical and non clinical uses. Studies are being carried out on the elimination of side effects of blood substitutes and extensive clinical trials are being conducted to test their safety and efficacy. Artificial blood substitutes could only be used clinically for patient management following clinical trials and approvals, and will be the ultimate global solution to the problems associated with donor scarcity, blood collection and transfusion-mediated diseases. [Archives Medical Review Journal 2012; 21(2.000: 95-108

  8. 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

  9. 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-containin......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....

  10. 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

  11. 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

  12. Radioactivity and Environment

    International Nuclear Information System (INIS)

    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)

  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. From meandering to straight grain boundaries: Improving the structures of artificially-induced grain boundaries in superconducting YBa2Cu3Oy bicrystals

    International Nuclear Information System (INIS)

    This paper presents several key aspects of the successful approach to preparing artificially-induced [001] tilt YBa2Cu3Oy (YBCO) grain boundaries (GBs) with uniform, well-defined structures. The authors have compared the structure of GBs produced in thin film bicrystals and bulk bicrystals, respectively. In the YBCO thin film bicrystals prepared by off-axis magnetron sputtering, meandering rather than planar GBs were generally formed due to the three-dimensional island-shaped nucleation and growth of the thin films. Experimentally, using a low film deposition rate has been demonstrated to reduce the magnitude of meander. However, complete elimination of the meandering configuration has not yet been accomplished due to the film growth mechanism. Thus, the authors have developed a dual-seeded-melt-texture process to produce uniform, planar GBs in [001] tilt YBCO bulk bicrystals. Transmission electron microscopy (TEM) studies revealed GBs with a remarkably planar configuration on both micro and nano-meter scales, demonstrating that simpler, meander-free GB microstructures with well defined [001] tilt angle have been successfully produced compared to those formed in bicrystal thin films. The high reproducibility, excellent stability and well controlled GB orientations have established the dual-seeded-melt-texture process as a reliable technique for engineering artificial GBs for the purpose of systematic studies of GB properties and allow for more insightful measurements of transport properties across individual GBs

  15. Radioactive Iodine

    Science.gov (United States)

    ... Giving Workplace Giving Other Ways to Donate Radioactive Iodine Iodine is essential for proper function of the ... that takes up and holds onto iodine. Radioactive Iodine FAQs WHAT IS RADIOACTIVE IODINE (RAI)? Iodine, in ...

  16. 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

  17. 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.

  18. Residual neutron-induced radio-activities in samples exposed in Hiroshima

    International Nuclear Information System (INIS)

    Among the radionuclides that have been detected in materials exposed to the nuclear explosions in Hiroshima and Nagasaki, 152Eu, 154Eu, and 60Co can be measured even today by using high-sensitivity gamma-ray counting techniques. Since 152Eu, 154Eu and 60Co are produced principally from stable isotopes of europium and cobalt by neutron capture reactions, they are useful radionuclides for checking the validity of a series of computer calculations employed for the reassessment of atomic bomb neutron dosimetry in Hiroshima and Nagasaki (chapter 5). The use of 152Eu, 154Eu and 60Co for the reassessment of A-bomb neutron dosimetry, however, has been limited by the following difficulties: 1) today, these radionuclides are found only at extremely low concentrations in materials exposed to the nuclear explosions; and 2) the neutrons that induced these radionuclides were thermal and epithermal, while the neutron dose received in Hiroshima and Nagasaki is attributable mainly to fast neutrons. In the present work, for the purpose of obtaining information on fast neutron fluence in Hiroshima, the depth distribution of the activity of 152Eu to the abundance of stable Eu, 152Eu/Eu, was studied, using a thick sample exposed to the Hiroshima A-bomb. Furthermore, a proposal to analyze thermal and epithermal neutron fluences from a set of data of 152Eu/Eu, 154Eu/Eu, and 60Co/Co was examined, using samples exposed to the Hiroshima A-bomb in the vicinity of the hypocenter. For the reliable and simultaneous determination of 152Eu/Eu, 154Eu/Eu and 60Co/Co, chemical extraction of Eu and Co from the exposed sample was studied. The procedure to prepare samples enriched in Eu and Co was also applied to samples exposed to the Hiroshima A-bomb at locations 1300 m from the hypocenter, because determination of 152Eu is extremely difficult without chemical enrichment of Eu from samples exposed to the A-bomb at locations greater than 1000 m from the hypocenter

  19. 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)

  20. Transportation of radioactive elements

    International Nuclear Information System (INIS)

    The production and marketing of artificial radioactive elements engaged in by the 'Office des Rayonnements Ionisants' requires the use of specially designed packagings and assorted means of transport. The authors begin by describing the different kinds of products involved and the forms of packagings needed, and go on to discuss the various means of transport used, underlining the fact that, in terms of number and gravity, the incidents that have occurred to date have indeed been few and far between

  1. Radioactivity [includes radioactivity levels

    International Nuclear Information System (INIS)

    The Environmental Digest for Wales is prepared on a regular basis by the Welsh Office and brings together data on the Welsh environment from a number of sources. Most of the information contained in the tables is collected as part of continuous monitoring programmes and will be updated in future editions. Some tables contain information collected only once as part of a survey or study, and will not be included in future volumes of the series. The section on Radioactivity includes tables of concentration in air, rainwater, milk, fish and gives details of the liquid radioactive wastes discharged from Welsh nuclear power stations (at Wylfa and Trawsfynydd) and the gamma dose rates around Welsh nuclear power stations. An appendix includes a glossary of terms used, the units of radioactivity and a list of radionuclides present in the environment. (author)

  2. Artificial Intelligence.

    Science.gov (United States)

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

    2016-04-01

    It seems natural to think that the same prudential and ethical reasons for mutual respect and tolerance that one has vis-à-vis other human persons would hold toward newly encountered paradigmatic but nonhuman biological persons. One also tends to think that they would have similar reasons for treating we humans as creatures that count morally in our own right. This line of thought transcends biological boundaries-namely, with regard to artificially (super)intelligent persons-but is this a safe assumption? The issue concerns ultimate moral significance: the significance possessed by human persons, persons from other planets, and hypothetical nonorganic persons in the form of artificial intelligence (AI). This article investigates why our possible relations to AI persons could be more complicated than they first might appear, given that they might possess a radically different nature to us, to the point that civilized or peaceful coexistence in a determinate geographical space could be impossible to achieve. PMID:26957450

  3. 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 ...

  4. Ambient radioactivity levels and radiation doses. Annual report 2013

    International Nuclear Information System (INIS)

    The report on environmental radioactivity and radiation exposure 2013 includes data concerning the following issues: sources of natural and artificial radioactivity, radon in buildings, radioactive materials in construction materials and industrial products, nuclear weapon tests, the consequences of reactor accidents in Chernobyl and Fukushima, nuclear facilities, occupational exposure, radiation exposure from medical applications, handling of radioactive materials in research and technology, radioactive wastes, radiation accidents and specific incidents.

  5. Does Artificial Ascites Induce the Heat-Sink Phenomenon during Percutaneous Radiofrequency Ablation of the Hepatic Subcapsular Area?: an in vivo Experimental Study Using a Rabbit Model

    International Nuclear Information System (INIS)

    To evaluate the effect of the heat-sink phenomenon induced by artificial ascites on the size of the ablation zone during percutaneous radiofrequency (RF) ablation of the hepatic subcapsular area in an in vivo rabbit model. A total of 21 percutaneous rabbit liver RF ablations were performed with and without artificial ascites (5% dextrose aqueous solution). The rabbits were divided into three groups: a) control group (C, n = 7); b) room temperature ascites group (R, n = 7); and c) warmed ascites group (W, n = 7). The tip of a 1 cm, internally cooled electrode was placed on the subcapsular region of the hepatic dome via ultrasound guidance, and ablation was continued for 6 min. Changes in temperature of the ascites were monitored during the ablation. The size of the ablation zones of the excised livers and immediate complications rates were compared statistically between the groups (Mann-Whitney U test, Kruskal-Wallis test, linear-by-linear association, p = 0.05). One rabbit from the 'W' group expired during the procedure. In all groups, the ascites temperatures approached their respective body temperatures as the ablations continued; however, a significant difference in ascites temperature was found between groups 'W' and 'R' throughout the procedures (39.2± 0.4 .deg. C in group W and 33.4±4.3 .deg. C in group R at 6 min, p = 0.003). No significant difference was found between the size of the ablation zones (782.4±237.3 mL in group C, 1,172.0±468.9 mL in group R, and 1,030.6±665.1 mL in group W, p = 0.170) for the excised liver specimens. Diaphragmatic injury was identified in three of seven cases (42.9%) upon visual inspection of group 'C' rabbits (p = 0.030). Artificial ascites are not likely to cause a significant heat-sink phenomenon in the percutaneous RF ablation of the hepatic subcapsular region

  6. Does Artificial Ascites Induce the Heat-Sink Phenomenon during Percutaneous Radiofrequency Ablation of the Hepatic Subcapsular Area?: an in vivo Experimental Study Using a Rabbit Model

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Young Sun; Rhim, Hyun Chul; Choi, Dong Il; Lim, Hyo K. [Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul (Korea, Republic of)

    2009-02-15

    To evaluate the effect of the heat-sink phenomenon induced by artificial ascites on the size of the ablation zone during percutaneous radiofrequency (RF) ablation of the hepatic subcapsular area in an in vivo rabbit model. A total of 21 percutaneous rabbit liver RF ablations were performed with and without artificial ascites (5% dextrose aqueous solution). The rabbits were divided into three groups: a) control group (C, n = 7); b) room temperature ascites group (R, n = 7); and c) warmed ascites group (W, n = 7). The tip of a 1 cm, internally cooled electrode was placed on the subcapsular region of the hepatic dome via ultrasound guidance, and ablation was continued for 6 min. Changes in temperature of the ascites were monitored during the ablation. The size of the ablation zones of the excised livers and immediate complications rates were compared statistically between the groups (Mann-Whitney U test, Kruskal-Wallis test, linear-by-linear association, p = 0.05). One rabbit from the 'W' group expired during the procedure. In all groups, the ascites temperatures approached their respective body temperatures as the ablations continued; however, a significant difference in ascites temperature was found between groups 'W' and 'R' throughout the procedures (39.2+- 0.4 .deg. C in group W and 33.4+-4.3 .deg. C in group R at 6 min, p = 0.003). No significant difference was found between the size of the ablation zones (782.4+-237.3 mL in group C, 1,172.0+-468.9 mL in group R, and 1,030.6+-665.1 mL in group W, p = 0.170) for the excised liver specimens. Diaphragmatic injury was identified in three of seven cases (42.9%) upon visual inspection of group 'C' rabbits (p = 0.030). Artificial ascites are not likely to cause a significant heat-sink phenomenon in the percutaneous RF ablation of the hepatic subcapsular region

  7. 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

  8. 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

  9. 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)

  10. 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)

  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. 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.

  13. 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

  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. 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.

  16. 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.

  17. 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.

  18. 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

  19. 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...

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

    OpenAIRE

    Moseley, G. Lorimer; Olthof, Nick; Venema, Annemeike; Don, Sanneke; Wijers, Marijke; Gallace, Alberto; Spence, Charles

    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...

  1. Artificial halos

    Science.gov (United States)

    Selmke, Markus

    2015-09-01

    Judged by their frequency and beauty, ice halos easily rival rainbows as a prominent atmospheric optics phenomenon. This article presents experimental halo demonstrations of varying complexity. Using a single commercially available hexagonal glass prism, a variety of artificial halos can be simulated. The experiments include laser beam path analysis, a modified classic spinning prism experiment, and a novel Monte-Carlo machine for three-dimensional rotations. Each of these experiments emulates different conditions of certain halo displays, and in combination, they allow a thorough understanding of these striking phenomena.

  2. 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...

  3. 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)

  4. Airborne measurement of radioactivity

    International Nuclear Information System (INIS)

    The German Meteorological Service (Deutscher Wetterdienst, DWD) is responsible for the surveillance of radioactivity in the atmosphere. In case of an radioactive emergency radioactive plumes may be expected in heights up to the tropopause depending on the type of accident. For this reason aircraft measurements are necessary as a supplement to groundbased measuring sites, especially in case of non available details about the source of radioactive release and lack of details about the accident. The authors present an aircraft type Learjet 35A used for localizing radioactive contaminated air masses up to 10,000 m and the measurement of artificial radionuclides on aerosols. For this purpose the aircraft is equipped with an isokinetic high-volume sampler for collection of aerosols on filters outside the pressurized cabin and an onboard gamma spectrometry system with a high purity germanium detector to analyze the interchangeable contaminated filters during flight as well as a dose ratemeter and a GPS (Global Positioning System) for navigation. The collection of gaseous iodine is optional. The meteorological parameters temperature, atmospheric pressure, relative humidity, wind speed and wind direction are determined as well. Resulting data are transmitted by global VHF datalink from the plane to the DWD headquarter and used for verifying the prognosis. (orig.)

  5. 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)

  6. Radioactive wastes

    International Nuclear Information System (INIS)

    The standard deals with the management of radioactive wastes originating from radioactive isotopes and the operation of nuclear reactors and non-energetic nuclear power plants. It contains seven chapters: general aspects (the categories applied here were standardised in MSZ 62 and MSZ 14341/1), collection of radioactive wastes, temporary storage, tables of the quantities of dischargable isotopes, processing, transportation, and permanent storage of radioactive wastes. The standard became valid in Hungary on January 1, 1981. (Sz.J.)

  7. 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.

  8. 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.

  9. The development neurotoxicity of ethanol: Cerebral cortical cholinergic alterations induced in artificially reared rats exposed to ethanol during the brain growth spurt

    International Nuclear Information System (INIS)

    It is hypothesized that cerebral cortical cholinergic neurotransmitter system alterations are induced by ethanol exposure during the vulnerable period of rapid brain growth. To test this proposal, on postnatal (PN) day 4, male Sprague Dawley rat pups were randomly assigned to either mother raised control (MRC) or artificially reared (AR) experimental groups. AR, ethanol-exposed (EE) pups received a liquid diet containing either 3%, 4%, or 5% (w/v) ethanol, while AR, cup-control (CC) pups isovolumetrically received an isocaloric, glucose-substituted diet. Acute effects of AR (CC vs MRC) and EE (EE vs CC) were determined in groups of pups sacrificed immediately following the termination of AR on PN8. Other groups of neonates were returned to foster dams on PN8 and maternally reared until sacrifice on PN20 to detect persistent or latent alternations. Although AR failed to perturb muscarinic receptor density at either age of assessment, it acutely and persistently decreased receptor affinity for (3H)QNB, and also the activities of both acetylcholinesterase and choline acetyltransferase

  10. 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.

  11. 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

  12. Radioactive wastes

    International Nuclear Information System (INIS)

    The Standard determines the terms and categories of radioactive wastes originating from the application of radioactive isotopes and operation of nuclear reactors and non-energetic nuclear power plants. The terms of dosimetry, the classification of different radioactive sources (open an sealed sources, etc.), the danger classes of isotopes, the categorization of isotope laboratories (A-, B-, and C-level) are given. The waste categories, the minimal concentration and total activity values for qualifying any solid, liquid, biological or gaslike material as radioactive waste, a table for the most important isotopes, and another for unknown isotope compositions, the categories of liquid and gaslike radioactive wastes are also given. (Sz.J.)

  13. 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 ...

  14. 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)

  15. 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)

  16. 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.

  17. 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.

  18. Artificial Sperm

    Directory of Open Access Journals (Sweden)

    Nolte J

    2013-01-01

    Full Text Available Spermatogenesis is a complex mechanism that is controlled by an extensive network of hormonal activities within an outstanding organized and structured tissue. Spermatogonial stem cells (SSCs provide the basis of lifelong spermatogenesis by renewing the pool of SSCs balanced with differentiation into spermatogonia which will than give rise to spermatozoa. The process of spermatogenesis has been investigated by scientists all over the world for many decades. To understand the mechanisms leading to the development of haploid gametes originating from a stem cell, is at the same time fascinating and important since this is the process that leads to the next generation. To have a tool for the investigation of this outstanding process, the establishment of robust protocols for the in vitro generation and differentiation of spermatozoa is necessary. However, it is not only important for understanding the basics of spermatogenesis but also to create ex vivo systems for the generation of artificial sperm starting from immature germ cells from infertile patients.

  19. Radioactivity. Centenary of radioactivity discovery; Radioactivite. Centenaire de la decouverte de la radioactivite

    Energy Technology Data Exchange (ETDEWEB)

    Charpak, G. [Academie des Sciences, 75 - Paris (France); Tubiana, M. [Academie de Medecine, 75 - Paris (France); Bimbot, R. [Institut National de Physique Nucleaire et de Physique des Particules (India2P3), 75 - Paris (France)

    1997-12-31

    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.)

  20. 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.)

  1. 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)

  2. Artificial tracers in geothermal hydrology

    International Nuclear Information System (INIS)

    The literature on the use of artificial tracers in geothermal hydrology published during the last ten years is reviewed. The characteristics of hot water systems which may limit the choice of tracers are considered and tracer injection, sampling and measuring methods are noted. A strategy for running a tracer testing programme is suggested and the experiences of investigators in using a range of radioactive, chemical and dye tracers are reported. Comparisons of the limits of detection of the more commonly used tracers quoted by various workers have been made along with typical amounts of tracer used and costs of making the tests. (author). 32 refs, 1 fig., 2 tabs

  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. Specific Radioactivity of Neutron Induced Radioisotopes: Assessment Methods and Application for Medically Useful 177Lu Production as a Case

    Directory of Open Access Journals (Sweden)

    Van So Le

    2011-01-01

    Full Text Available The conventional reaction yield evaluation for radioisotope production is not sufficient to set up the optimal conditions for producing radionuclide products of the desired radiochemical quality. Alternatively, the specific radioactivity (SA assessment, dealing with the relationship between the affecting factors and the inherent properties of the target and impurities, offers a way to optimally perform the irradiation for production of the best quality radioisotopes for various applications, especially for targeting radiopharmaceutical preparation. Neutron-capture characteristics, target impurity, side nuclear reactions, target burn-up and post-irradiation processing/cooling time are the main parameters affecting the SA of the radioisotope product. These parameters have been incorporated into the format of mathematical equations for the reaction yield and SA assessment. As a method demonstration, the SA assessment of 177Lu produced based on two different reactions, 176Lu (n,?177Lu and 176Yb (n,? 177Yb (?- decay 177Lu, were performed. The irradiation time required for achieving a maximum yield and maximum SA value was evaluated for production based on the 176Lu (n,?177Lu reaction. The effect of several factors (such as elemental Lu and isotopic impurities on the 177Lu SA degradation was evaluated for production based on the 176Yb (n,? 177Yb (?- decay 177Lu reaction. The method of SA assessment of a mixture of several radioactive sources was developed for the radioisotope produced in a reactor from different targets.

  5. Radioactivity; La radioactivite

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1998-08-01

    This educative booklet give a general overview of radioactivity: history, structure of matter, radiations, radioactivity law, origin of radioactivity, radioactivity uses, radioprotection and measurement units. (J.S.)

  6. Japan Atomic Energy Research Institute/United States Integral Neutronics Experiments and Analyses for tritium breeding, nuclear heating, and induced radioactivity

    International Nuclear Information System (INIS)

    A large member of integral experiments for fusion blanket neutronics were performed using deuterium-tritium (D-T) neutrons at the Fusion Neutronics Source facility as part of a 10-yr collaborative program between the Japan Atomic Energy Research Institute and the United States. A number of measurement techniques were developed for tritium production, induced radioactivity, and nuclear heating. Transport calculations were performed using three-dimensional Monte Carlo and two-dimensional discrete ordinates codes and the latest nuclear data libraries in Japan and the United States. Significant differences among measurement techniques and calculation methods were found. To assure a 90% confidence level for tritium breeding calculations not to exceed measurements, designers should use a safety factor > 1.1 to 1.2, depending on the calculation method. Such a safety factor may not be affordable with most candidate blanket designs. Therefore, demonstration of tritium self-sufficiency is recommended as a high priority for testing in near-term fusion facilities such as the International Thermonuclear Experimental Reactor (ITER). The radioactivity measurements were performed for > 20 materials with the focus on gamma emitters with half-lives < 5 yr. Most discrepancies were attributed directly to deficiencies in the activation libraries, particularly errors in cross sections for certain reactions. 71 refs., 30 figs., 5 tabs

  7. 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)

  8. 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.)

  9. A high-efficiency compact setup to study evaporation residues formed in reactions induced by low-intensity radioactive ion beams

    International Nuclear Information System (INIS)

    A setup for measuring cross-sections of evaporation residues produced in the collision of two heavy ions is described. The system, which detects all reaction products in a narrow angular range around the beam direction, is designed to work best with low-intensity beams (=5ions/s) and can be highly efficient for reactions studied in inverse kinematic conditions, i.e., heavy-mass beam on lighter-mass targets. The system as presented here has been optimized to study evaporation residues from reactions induced by radioactive ion beams with charges near Z?50 and energies near 4MeV/nucleon. Continuous sampling of the beam velocity, energy loss and position allow for the measurement of accurate evaporation residue cross-sections also in situations where the beam contains a mixture nuclides

  10. 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)

  11. 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)

  12. 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

  13. Radionuclides induced by environmental neutrons. Discovery of natural radioactive Eu and Co isotopes and their contribution to the evaluation of Atomic-bombing neutrons in Hiroshima and Nagasaki

    International Nuclear Information System (INIS)

    Radioactive europium and cobalt isotopes induced by environmental neutrons have been discovered by low-background Ge detector installed in Ogoya underground laboratory. Specific activities of 152Eu, 154Eu and 155Eu and 60Co were measured for recent and old europium and cobalt reagents. Observed activities are 0.06-0.52 dpm g-1 for 152Eu, 0.09-0.16 dpm g-1 for 154Eu and 0.005-0.16 dpm g-1 for 155Eu and 0.007-0.083 dpm g-1 for 60Co. Contribution of natural 152Eu and 60Co in Atomic-bomb exposed samples are found to be negligible low and less than 10%, respectively. (author)

  14. 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.

  15. 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.

  16. 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)

  17. 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

  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. 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)

  20. 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.)

  1. 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

  2. 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.

  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. 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)

  5. Application of a series of artificial neural networks to on-site quantitative analysis of lead into real soil samples by laser induced breakdown spectroscopy

    International Nuclear Information System (INIS)

    Artificial neural networks were applied to process data from on-site LIBS analysis of soil samples. A first artificial neural network allowed retrieving the relative amounts of silicate, calcareous and ores matrices into soils. As a consequence, each soil sample was correctly located inside the ternary diagram characterized by these three matrices, as verified by ICP-AES. Then a series of artificial neural networks were applied to quantify lead into soil samples. More precisely, two models were designed for classification purpose according to both the type of matrix and the range of lead concentrations. Then, three quantitative models were locally applied to three data subsets. This complete approach allowed reaching a relative error of prediction close to 20%, considered as satisfying in the case of on-site analysis. - Highlights: • Application of a series of artificial neural networks (ANN) to quantitative LIBS • Matrix-based classification of the soil samples by ANN • Concentration-based classification of the soil samples by ANN • Series of quantitative ANN models dedicated to the analysis of data subsets • Relative error of prediction lower than 20% for LIBS analysis of soil samples

  6. 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

  7. 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)

  8. Transformation and clustering of defects induced by electron irradiation in barium hollandite ceramics for radioactive cesium storage: Electron paramagnetic resonance study

    Science.gov (United States)

    Aubin-Chevaldonnet, V.; Gourier, D.; Caurant, D.; Costantini, J.-M.

    2012-04-01

    Barium hollandite-type ceramics have been envisaged for the immobilization of radioactive cesium. To evaluate their stability under irradiation, a hollandite ceramic of composition Ba1.16Al2.32Ti5.68O16 was irradiated with electrons at a temperature close to room temperature to simulate the effect of ?- and ?-decays of cesium. Ti3+ and O2- paramagnetic defects induced by electron irradiation [V. Aubin-Chevaldonnet et al., J. Phys.: Condens. Matter 18, 4007 (2006)] were detected by electron paramagnetic resonance. As the temperature in the bulk of the hollandite waste form could reach 300 °C at the beginning of the storage, the thermal stability of these paramagnetic defects was also studied. Isothermal annealing treatments at 300 °C and isochronal annealing treatments between 50 °C and 800 °C show that the irradiation induced Ti3+ (E1 and E2 centers) and O2- (H centers) do not recombine. Instead, they partially transform during annealing, respectively, into titanyl TiO+ centers (E3 centers) at the grain surface and into paramagnetic clusters of O2- of less than 10 nm size (G2 centers), trapped in the bulk of the grains. These oxygen-rich aggregates could prefigure the formation of molecular oxygen observed in electron irradiated glasses.

  9. 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.)

  10. 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

  11. 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...

  12. Ambient radioactivity levels and radiation doses. Annual report 2013; Umweltradioaktivitaet und Strahlenbelastung. Jahresbreicht 2013

    Energy Technology Data Exchange (ETDEWEB)

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

    2015-04-15

    The report on environmental radioactivity and radiation exposure 2013 includes data concerning the following issues: sources of natural and artificial radioactivity, radon in buildings, radioactive materials in construction materials and industrial products, nuclear weapon tests, the consequences of reactor accidents in Chernobyl and Fukushima, nuclear facilities, occupational exposure, radiation exposure from medical applications, handling of radioactive materials in research and technology, radioactive wastes, radiation accidents and specific incidents.

  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. Risk analysis of radioactive waste disposal in salt deposits

    International Nuclear Information System (INIS)

    The use of salt mines and artificial holes in salt deposits for definitive storage of radioactive wastes is discussed. A risk analysis is made with special attention to geological effects and long term radionuclide migration. Other natural causes of a come back of radioactive nuclides in the biosphere could be neglected. The risks as a consequence of human actions have been neglected

  15. Radioactivity in the Irish marine environment

    International Nuclear Information System (INIS)

    The Nuclear Energy Board, for many years, has been surveying the levels of radioactivity in marine organisms and water samples taken from the seas around Ireland. This report shows the results of the past decade's survey and the hazards posed by radioactivity from artificial sources such as Sellafield, which are now small by comparison with doses received from natural sources. The report concludes that the water surrounding Ireland functions as a barrier against the worst effects of the Sellafield discharges and tha seas and beaches have remained safe as far as radioactive contamination is concerned

  16. New radioactivities

    International Nuclear Information System (INIS)

    Radioactivities emerge as ambassadors from a distant world, the nucleus of an atom. The nucleus sends forth a flash of energy; a couple of protons, a few neutrons or other particles. Each of these ambassadors carries a particular message. Most often they announce the decay of a nucleus from an energetic, unstable state to a less energetic, more stable state to a less energetic, more stable one. Radioactivities also reveal subtle clues about nuclear structure. By piecing these clues together, investigators have created detailed models of the nucleus. The models not only account for most nuclear phenomena but also predict many new types of radioactivities. Until the 1980's it appeared as though the nuclear fragments from radioactive processes came in roughly three sizes: four, 100 or 200 nucleons. In the four-nucleon range is the alpha particle, or helium nucleus. If an alpha particle emerges from an atom, it leaves behind a nucleus composed of approximately 200 nucleons. In the 100-nucleon range are the fragments from fission, a process in which a heavy nucleus splits roughly in half. The restricted range of sizes raised an intriguing question: Why did a nucleus not emit a fragment composed of other quantities of nucleons--why not 14 or 24? Today it is known that a nucleus can indeed eject a fragment of this size or any other. These new radioactivities form when a large number of nucleons within the nucleus spontaneously rearrange themselves in certain configurations

  17. 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

  18. 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...

  19. 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.

  20. 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

  1. FY1995 new technology of artificial organ materials which can induce host biocompatibility; 1995 nendo jinko zokiyo seitai kino fukatsukagata sozai no kaihatsu gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-05-01

    The aim of this project is to produce a highly biocompatible materials for next generation's artificial organs using the following methods: 1, Micromodification of polymer materials. 2, Biocompatible treatment for biological materials. 3, Application of bioabsorbable materials. 4, Bioactive substance immobilization. and 5, Use of autologous tissue as artificial organ materials. As a synthetic polymer material, microporous polyurethane was used for a small diameter vascular prosthesis. The graft with this technology was successfully implanted in rat abdomical aortic position. The graft of 1.5 mm in internal diameter and 10 cm in length showed excellent patency with nice endothelialisation. As a biological material, microfibers of collagen was used for a sealing substance of vascular prothesis. The microfibers absorbed a large amount of water, which could prevent blood leakage from the graft wall. The graft showed non-thrombogenic property and excellent host cell affinity, resulted in rapid neointima formation. As to autologous tissue, bone marrow was used, since marrow cells can differentiate into any mesenchimal cells with synthesis of growth factors. Marrow cell transplanted vascular prothesis showed rapid capillary ingrowth. These results indicated that the newly designed materials had suitable properties for materials of next generation's artificial organs. (NEDO)

  2. FY1995 new technology of artificial organ materials which can induce host biocompatibility; 1995 nendo jinko zokiyo seitai kino fukatsukagata sozai no kaihatsu gijutsu

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-12-01

    The aim of this project is to produce a highly biocompatible materials for next generation's artificial organs using the following methods: 1, Micromodification of polymer materials. 2, Biocompatible treatment for biological materials. 3, Application of bioabsorbable materials. 4, Bioactive substance immobilization. and 5, Use of autologous tissue as artificial organ materials. As a synthetic polymer material, microporous polyurethane was used for a small diameter vascular prosthesis. The graft with this technology was successfully implanted in rat abdomical aortic position. The graft of 1.5 mm in internal diameter and 10cm in length showed excellent patency with nice endothelialisation. As a biological material, microfibers of collagen was used for a sealing substance of vascular prothesis. The microfibers absorbed a large amount of water, which could prevent blood leakage from the graft wall. The graft showed non-thrombogenic property and excellent host cell affinity, resulted in rapid neointima formation. As to autologous tissue, bone marrow was used, since marrow cells can differentiate into any mesenchimal cells with synthesis of growth factors. Marrow cell transplanted vascular prothesis showed rapid capillary ingrowth. These results indicated that the newly designed materials had suitable properties for materials of next generation's artificial organs. (NEDO)

  3. History of radioactivity

    International Nuclear Information System (INIS)

    The author describes the historical development of the physics of atoms and nuclei. After a consideration of the ancient Greek philosophy concerning atoms the behaviour of gases is discussed with regards to statistical mechanics. Then the developement of chemistry from alchemy is described. Thereafter the early studies of gas discharges are described with regards to the electronic structure of atoms. In this connection the periodic system of elements is considered. Then the detection of the ?-radiation of Uranium by Becquerel and the detections of M. and P. Curie are described. Thereafter the radiactive decay of nuclei is discussed. Then a popular introduction into nuclear structure is given with special regards to artificial radioactivity and nuclear fission. Finally nuclear reactors, the atomic bombs, applications of radionuclides, and problems of radiation protection are described. (HSI)

  4. From Polonium to Artificial Radioisotopes in the 1930's

    International Nuclear Information System (INIS)

    The word '' radioactive '' appeared for the first time in Pierre and Marie Curie's paper announcing the discovery of Polonium. Starting with the memory of this seminal event and the discovery of Radium, we focus on a few of the tremendous successes achieved in the 30's, namely the successive discoveries of the neutron and the positive electron, followed by the discoveries of artificial radioactivity and later of fission. Experimentalists were confronted with many problems as their interest shifted from radioactivity to '' artificial disintegration '' and cosmic rays experiments. The first discovered ?+ radioactive isotopes, 30P and 13N, and the first fission produced nuclei appear as early steps towards the quest for more and more exotic nuclei. (author)

  5. 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

  6. 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.

  7. Radioactive waste

    International Nuclear Information System (INIS)

    In the authors' view, plutonium production, as well as soil dumping of radioactive waste, should halt immediately: the public dangers are simply too high. DOE's de facto outlaw status in complying with environmental laws must also change. EPA should be able to enforce the same standards for DOE as for the private sector. And the only way to ensure that DOE effectively cleans up its wastes is to set up a long-term spending mechanism such as Superfund. Regardless of how these issues are resolved, the radioactive and hazardous material that is the legacy of the nuclear arms race will affect surrounding communities for centuries

  8. Radioactivity and the French uranium bearing minerals

    International Nuclear Information System (INIS)

    This special issue of Regne Mineral journal is entirely devoted to the French uranium mining industry. It comprises 4 parts dealing with: the uranium mining industry in France (history, uranium rush, deposits, geologic setting, prosperity and recession, situation in 1998, ore processing); radioactivity and the uranium and its descendants (discovery, first French uranium bearing ores, discovery of radioactivity, radium and other uranium descendants, radium mines, uranium mines, atoms, elements and isotopes, uranium genesis, uranium decay, isotopes in an uranium ore, spontaneous fission, selective migration of radionuclides, radon in mines and houses, radioactivity units, radioprotection standards, new standards and controversies, natural and artificial radioactivity, hazards linked with the handling and collecting of uranium ores, conformability with radioprotection standards, radioactivity of natural uranium minerals); the French uranium bearing minerals (composition, crystal structure, reference, etymology, fluorescence). (J.S.)

  9. 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...

  10. Experimental verification of the current data and methods for induced radioactivity and decay heat calculation in D-T fusion reactors

    International Nuclear Information System (INIS)

    Induced radioactivities and decay heat are of significant importance in the nuclear design of a near-term D-T fusion device from the view point of the safety consideration. In the framework of the JAERI/USDOE collaborative program on fusion neutronics, extensive experimental efforts have been devoted to verify the validity of the calculation code systems THIDA-2, REACT-2 and DKR-ICF. In the previous study, it was clearly pointed out that there were large discrepancies for several important materials between the experiment and the calculation in terms of y-ray emission rates. This paper investigated the major sources of these large discrepancies. In addition to the previous ones, the analysis was carried out by THIDA-2 using an updated cross-section library. As a result, the following was pointed out: (1) The calculation of THIDA with the new activation cross-section library gave better agreement with experiment, especially for MnCu, W, Mo and V. As far as the higher neutron energy range above 1.0 MeV is concerned, all calculation code systems offer reasonable prediction accuracy. (2) For MnCu, W and Ta, uncertainty in the neutron spectrum was the main source for the large discrepancies because low-energy neutrons were very sensitive to the capture reaction products of 64Cu, 187W and 182Ta. (orig.)

  11. 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

  12. Radioactive wastes

    International Nuclear Information System (INIS)

    Included in the radioactive waste literature review for 1981 were three symposia summarized in four tables. The remaining literature has been divided into ten categories: general programs, isolation, waste treatment, waste management, storage, environmental transport, monitoring, transportation, risk assessment, remedial action, and socioeconomics. Included are 193 references

  13. Radioactive Waste.

    Science.gov (United States)

    Blaylock, B. G.

    1978-01-01

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

  14. 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

  15. High energy muon induced radioactive nuclides in nickel plate and its use for 2-D muon-beam image profile

    Science.gov (United States)

    Kurebayashi, Y.; Sakurai, H.; Takahashi, Y.; Doshita, N.; Kikuchi, S.; Tokanai, F.; Horiuchi, K.; Tajima, Y.; Oe, T.; Sato, T.; Gunji, S.; Inui, E.; Kondo, K.; Iwata, N.; Sasaki, N.; Matsuzaki, H.; Kunieda, S.

    2015-11-01

    Target materials were exposed to a muon beam with an energy of 160 GeV/c at the COMPASS experiment line in CERN-SPS to measure the production cross-sections for muon-induced radionuclides. A muon imager containing four nickel plates, each measuring 100 mm×100 mm, exposed to the IP plate successfully detected the muon beam image during an irradiation period of 33 days. The contrasting density rate of the nickel plate was (5.2±0.7)×10-9 PSL/muon per one-day exposure to IP. The image measured 122 mm and 174 mm in horizontal and vertical lengths, respectively, in relation to the surface of the base, indicating that 50±6% of the muon beam flux is confined to an area of 18% of the whole muon beam. The number of muons estimated from the PSL value in the total beam image area (0.81±0.1)×1013 was comparable to the total muon counts of the ion-chamber at the M2 beam line in the CERN-SPS. The production cross-sections of Cr-51, Mn-54, Co-56, Co-57, and Co-58 in nickel were 0.19±0.08, 0.34±0.06, 0.5±0.05, 3.44±0.07, 0.4±0.03 in the unit of mb, respectively, reducing muon associated particles effects. They are approximately 10 times smaller than that a proceeding study by Heisinger et al.

  16. Artificial ferroelectricity in perovskite superlattices

    International Nuclear Information System (INIS)

    Artificial superlattices of SrZrO3(SZO)/SrTiO3(STO) were fabricated by molecular-beam epitaxy. Lattice parameters showed that the lattice distortion (c/a ratio) attained a maximum value in the [(SZO)10/(STO)10]4 superlattice. Dielectric relaxation was observed in the [(SZO)1/(STO)1]40 and [(SZO)10/(STO)10]4 superlattices in the low frequency domain. Dielectric permittivity of the SZO/STO superlattices was over 10 000 at 110 MHz. The SZO/STO superlattices showed clear Q-V hysteresis curves, which indicated that ferroelectricity was induced artificially in the superlattices in spite of the paraelectric nature of SZO and STO. The origin of the ferroelectricity was related to the anisotropic lattice distortion in the superlattice structure

  17. Quo Vadis, Artificial Intelligence?

    OpenAIRE

    Alfons Schuster; Daniel Berrar; Naoyuki Sato

    2010-01-01

    Since its conception in the mid 1950s, artificial intelligence with its great ambition to understand and emulate intelligence in natural and artificial environments alike is now a truly multidisciplinary field that reaches out and is inspired by a great diversity of other fields. Rapid advances in research and technology in various fields have created environments into which artificial intelligence could embed itself naturally and comfortably. Neuroscience with its desire to understand nervou...

  18. 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. ...

  19. 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

  20. 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.

  1. 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...

  2. 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

  3. Radioactive waste management

    International Nuclear Information System (INIS)

    This eighth chapter presents the radioactive wastes and waste disposal; classification of radioactive wastes; basis requests of the radioactive waste management; conditions for a radioactive waste disposal; registers and inventories; transport of radioactive wastes from a facility to another and the radioactive waste management plan

  4. Radioactive alchemy

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2014-07-15

    For any entity involved in radioactive waste management, turning lead into gold means succeeding with minimising the volumes and optimizing the long-term containment of ultimate waste to be disposed of. With this purpose, they perform R and D on different sorting, treatment and disposal technology, as explained by Frederic Plas from Andra (France), Jan Deckers from Belgoprocess (Belgium) and Wilhelm Bollingerfehr from DBE Technology (Germany). (orig.)

  5. 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.

  6. 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.)

  7. Influence of Artificial Sweetener on Human Blood Glucose Concentration

    OpenAIRE

    Ilse Skokan; P. Christian Endler; Beatrix Wulkersdorfer; Dieter Magometschnigg; Heinz Spranger

    2007-01-01

    Artificial sweeteners, such as saccharin or cyclamic acid are synthetically manufactured sweetenings. Known for their low energetic value they serve especially diabetic and adipose patients as sugar substitutes. It has been hypothesized that the substitution of sugar with artificial sweeteners may induce a decrease of the blood glucose. The aim of this study was to determine the reliability of this hypothesis by comparing the influence of regular table sugar and artificial sweeteners on the b...

  8. Artificial insemination in poultry

    Science.gov (United States)

    Artificial insemination is a relative simple yet powerful tool geneticists can employ for the propagation of economically important traits in livestock and poultry. In this chapter, we address the fundamental methods of the artificial insemination of poultry, including semen collection, semen evalu...

  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. 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.

  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. Radioactivity in Hocking River Basin

    International Nuclear Information System (INIS)

    Numerous studies have examined the environmental impacts and health hazards associated with man-made radioactive pollution. Within the last decade, however, there has been a growing awareness of the natural radiation environment. Very little is know about the way the natural radiation environment is affected when subjected to artificial stresses imposed by man's activities. The prolonged exposure from low level radioactivity may significantly affect our environment by altering the distribution of naturally occurring radionuclides through such processes as mining, water resources management or land reclamation. It is the intent of this study to examine more closely the way in which this radiological burden is altered by coal mining activities in an Appalachian watershed

  13. 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

  14. 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.

  15. Ensuring radioactivity monitoring in the French Polynesia environment

    International Nuclear Information System (INIS)

    The Laboratory of Environmental Study and Monitoring (LESE) of the French Institute of Radiation Protection and Nuclear Safety (IRSN) at Vairao (Tahiti, French Polynesia), has been performing a permanent monitoring of radioactivity in French Polynesia for more than 40 years. This mission has two objectives: - the follow up of radioactivity levels of artificial origin in all environments where Polynesian populations are living, as well as the radioactivity of the food products they consume; - the estimate of the doses received by the Polynesian populations exposed to this radioactivity. This plaquette briefly presents these two missions

  16. 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

  17. Occurence of natural and artificial radionuclides in the environment and methods of their detection

    International Nuclear Information System (INIS)

    The authors discuss occurence of radionuclides in the environment and illustrate the circulation of natural and artificial radioactive substances in the air, water and soil. Methods are presented of detecting radioactive contamination, including the sampling and detection of radiation emitted by radioactive isotopes contained in the samples. Various conditions as well as the kind of ionizing radiation emitters are taken into consideration. 19 refs. (author)

  18. 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

  19. 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).

  20. 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)

  1. 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 ...

  2. Melting artificial spin ice

    International Nuclear Information System (INIS)

    Artificial spin ice arrays of micromagnetic islands are a means of engineering additional energy scales and frustration into magnetic materials. Here we demonstrate a magnetic phase transition in an artificial square spin ice and use the symmetry of the lattice to verify the presence of excitations far below the ordering temperature. We do this by measuring the temperature-dependent magnetization in different principal directions and comparing it with simulations of idealized statistical mechanical models. Our results confirm a dynamical pre-melting of the artificial spin ice structure at a temperature well below the intrinsic ordering temperature of the island material. We thus create a spin ice array that has the real thermal dynamics of artificial spins over an extended temperature range. (paper)

  3. Development and application of artificial rainfall device

    International Nuclear Information System (INIS)

    An artificial sprinkling simulation device was designed and developed to be used for radioactive nuclides migration tests. In this device water drops are sprinkled through medical syringe needles which vibrate along a circle. After several year operation at the field test site, it was demonstrated that this device is stable and sprinkling homogeneous, with the rainfall intensity from 2 mm/h to 100 mm/h and the low limit of 2 mm/h. Compared with spraying nozzle, it is easy to control the rainfall quantity and sprinkling area, and the evaporation loss is small. The device can meet the requirement of radioactive nuclide migration test and may also be used for other purpose

  4. 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

  5. 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...

  6. 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...

  7. 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.

  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. 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...

  10. 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)

  11. 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.

  12. 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.

  13. 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)

  14. 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)

  15. Dissociation of Vertical Semiconductor Diatomic Artificial Molecules

    International Nuclear Information System (INIS)

    We investigate the dissociation of few-electron circular vertical semiconductor double quantum dot artificial molecules at 0T as a function of interdot distance. A slight mismatch introduced in the fabrication of the artificial molecules from nominally identical constituent quantum wells induces localization by offsetting the energy levels in the quantum dots by up to 2meV, and this plays a crucial role in the appearance of the addition energy spectra as a function of coupling strength particularly in the weak coupling limit

  16. 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)

  17. Radioactivity control of sediments in Serbia rivers

    International Nuclear Information System (INIS)

    In this paper we present the results of radioactivity control of the sediments in Serbian rivers from 2005 to 2008. Activity concentration of natural radionuclides in sediments (mean annual values in Bq/kg) in period 2005-2008 are within the average values limits on the territory of Serbia. Activities of long living radionuclide of artificial origin have tendency of mild decrease as a result of dissolution, leaching and changes in river flow. (author)

  18. 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...

  19. 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 ...

  20. 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.

  1. 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)

  2. 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)

  3. 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)

  4. 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)

  5. Experimental studies on utilization of argonless artificial air

    International Nuclear Information System (INIS)

    The radioactive argon produced in nuclear reactors causes environmental pollution. One of the substantial methods to reduce radioactive argon is the utilization of the artificial air with low argon content in reactor rooms. The artificial air close to natural air is obtainable by mixing commercial oxygen and nitrogen, however, there are some technical problems to be solved before it is solved. A small scale facility supplying artificial air was manufactured for trial, in order to find the optimum condition of controlling the mixing and to develop the continuous measurement method for the argon concentration in artificial air. In this study, the following facts have been found. For providing with the argonless artificial air close to natural air, the mixing of the gases evaporating from commercial liquid oxygen and nitrogen can be safely controlled. For the mixing control covering the wide range of flow rate, it is necessary to set up an auxiliary line in low flow range, in addition to the ordinary main line. The method of controlling the flow ratio of oxygen and nitrogen is not suitable to the control in low flow range. The oxygen concentration control method detecting it continuously is applicable to the control of whole flow range. The argon concentration is measured with an X-ray emission spectrometer. (Kako, I.)

  6. 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.

  7. 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.)

  8. 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.)

  9. 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.)

  10. Generalised Derived Limits for Selected Artificial Radionuclides in Foodstruffs

    International Nuclear Information System (INIS)

    The calculation of generalised derived limits for selected artificial radionuclides in foodstuffs consumed by the Indonesians have been carried out. The calculations is based on annual dose limit of 1 mSv for members of the public and the data on dose equivalent per unit of intake for the respective radionuclides, whilst the data of food consumption were taken from a survey conducted by The Central Bureau of Statistics. The generalised derived limits presented, as well as the derived investigation which the results of artificial radioactivity level monitoring in environmental foodstuffs can be compared. (author). 12 refs., 4 tabs

  11. 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.

  12. 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)

  13. 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.

  14. 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.

  15. 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

  16. A study of marine zoo-benthos of OM attouyour (systematic, ecology and radioactivity)

    International Nuclear Information System (INIS)

    This study introduces a survey of marine zoo-Benthos found in the littoral zone of Om Attouyour. Measuring natural and artificial radioactivity. Likewise, artificial radionuclides levels and Hg, Pb, Cd, Zn, and Cu concentrations were low or within the range measured for similar samples in other coasts of the Mediterranean. (author)

  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. 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

  19. 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)

  20. 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