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1

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

1996-01-01

2

Artificial Radioactivity Reference Horizons in Greenland Firn.  

Science.gov (United States)

Total beta measurements have been made on melt water samples from a stratigraphically dated firn core profile from the inland Greenland ice sheet (77 deg 10 min N, 61 deg 08 min W). A marked increase in radioactivity is found in the 1953 firn layer which ...

G. Crozaz C. C. Langway E. Picciotto

1966-01-01

3

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)

2013-07-01

4

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.

2011-04-01

5

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

1979-01-01

6

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)

1997-08-01

7

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

1994-01-01

8

Induced radioactivity in LDEF components  

Science.gov (United States)

A systematic study of the induced radioactivity of the Long Duration Exposure Facility (LDEF) is being carried out in order to gather information about the low earth orbit radiation environment and its effects on materials. The large mass of the LDEF spacecraft, its stabilized configuration, and long mission duration have presented an opportunity to determine space radiation-induced radioactivities with a precision not possible before. Data presented include preliminary activities for steel and aluminum structural samples, and activation subexperiment foils. Effects seen in the data show a clear indication of the trapped proton anisotropy in the South Atlantic Anomaly and suggest contributions from different sources of external radiation fluxes.

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

1992-01-01

9

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

Science.gov (United States)

Building materials and their additives contain radioactive isotopes, which can increase both external and internal radioactive exposures of humans. In this study Hungarian natural (adobe) and artificial (brick, concrete, coal slag, coal slag concrete and gas silicate) building materials were examined. We qualified 40 samples based on their radium equivalent, activity concentration, external hazard and internal hazard indices and the determined threshold values of these parameters. Absorbed dose rate and annual effective dose for inhabitants living in buildings made of these building materials were also evaluated. The calculations are based on (226)Ra, (232)Th and (40)K activity concentrations determined by gamma-ray spectrometry. Measured radionuclide concentrations and hence, calculated indices and doses of artificial building materials show a rather disparate distribution compared to adobes. The studied coal slag samples among the artificial building materials have elevated (226)Ra content. Natural, i.e. adobe and also brick samples contain higher amount of (40)K compared to other artificial building materials. Correlation coefficients among radionuclide concentrations are consistent with the values in the literature and connected to the natural geochemical behavior of U, Th and K elements. Seven samples (coal slag and coal slag concrete) exceed any of the threshold values of the calculated hazard indices, however only three of them are considered to be risky to use according to the fact that the building material was used in bulk amount or in restricted usage. It is shown, that using different indices can lead to different conclusions; hence we recommend considering more of the indices at the same time when building materials are studied. Additionally, adding two times their statistical uncertainties to their values before comparing to thresholds should be considered for providing a more conservative qualification. We have defined radon hazard portion to point to the limitations of the internal hazard considerations based on only measured (226)Ra 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. PMID:23246704

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

2013-04-01

10

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

2013-04-01

11

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)

1998-01-01

12

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.

2010-09-01

13

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)

1989-01-01

14

Natural and artificial radioactivity determination of some medicinal plants  

Energy Technology Data Exchange (ETDEWEB)

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.

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

15

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 "1"0"9I or "1"1"5Cs, 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

1984-10-08

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

1994-11-01

17

Induced Radioactivity Danger Parameter for Gamma Radiation.  

Science.gov (United States)

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...

D. R. Perry

1985-01-01

18

Studies of induced radioactivity at the AGS  

International Nuclear Information System (INIS)

With the goals of higher proton intensities, along with the many modes the AGS now runs and those being commissioned to run, we have begun detailed studies of the beam induced radioactivity in the AGS

1987-03-16

19

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)

1964-01-01

20

Application of artificial radioactive tracers for groundwater flow  

International Nuclear Information System (INIS)

In this work, the groundwater velocity was estimated by applying radioactive tracer techniques: the single well and the multiple well methods. In the first single well method, radioactive iodine-131 was injected in the well and the radioactivity was monitored with time. The groundwater flow was estimated as a function of the concentration dilution factor of the tracer taking into consideration the permeability of the filter screen and the aquifer. The second method (the multiple well technique) is based on direct measuring of the period of time the tracer needs to disperse from the injection well to one of receptor well arranged in a circle around the injection. The latter method was found to be more accurate and reliable and has also the advantage of determining the groundwater velocity and direction of flow as well. The limitations of the single well technique are discussed and a detailed comparison between single and multi-well techniques is given

1989-01-01

 
 
 
 
21

Natural and artificial radioactivity levels in the South Spanish environment  

International Nuclear Information System (INIS)

The study of the environmental behavior of radionuclides is a powerful tool for understanding the environment. The most recent results are reviewed, obtained by the authors' group from the measurement of anthropogenic and natural radioactivity in different natural compartments of the South of Spain. The levels of 99Tc and 137Cs in seaweed are presented; the presence and spread of U-isotopes in surface waters was also studied. Some details of the methodology used for radioactivity determination are outlined. (author) 2 tabs., 5 figs., 16 refs

1992-01-01

22

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)

1992-01-01

23

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

1984-01-01

24

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 "1"0"6Ru, "9"5Zr, "1"2"5Sb, "1"4"4Ce, and on the fraction smaller than 28?m for "1"0"6Ru, "9"5Zr, "1"2"5Sb, "1"4"4Ce, "6"5Zn, "1"0"3Ru, "1"1"0Ag, "1"3"4Cs, "1"4"1Ce, "1"5"5Eu. As regards "1"3"7Cs, 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

1976-01-01

25

Evaluation of induced radioactivity in 10 MeV-Electron irradiated spices, (2)  

International Nuclear Information System (INIS)

In order to check radioactivity of beta-emmitters produced by (?, 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? 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 ?-activities were detected. From the amount of observed radioactivities of ?-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 40K contained in the samples and, hence, its biological effects should be negligible. (author)

1994-02-01

26

Estimation of absorbed gamma dose in air due to natural and artificial radioactivity of soil  

International Nuclear Information System (INIS)

This Ph. D. thesis is devoted to the measurements of air absorbed gamma doses due to natural and artificial radioactivity in soil. It contains four chapters, conclusions, acknowledge, and a reference list. 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 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.). 42 Figs., 54+15 Tabs., 216 Refs, 1 App

1994-01-01

27

Radioactivity  

Energy Technology Data Exchange (ETDEWEB)

This item, from the Department of the Environment`s 1995 edition of the Digest of Environmental Statistics, provides information on the radiation exposure of the population from natural sources. Data is also drawn together on exposure of the public to artificial radiation, and on the discharge and disposal of radioactive wastes from nuclear facilities. (UK).

Anon.

1995-10-01

28

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

Energy Technology Data Exchange (ETDEWEB)

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 [sup 137]Cs 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).

Kritidis, P.; Kollas, J.G. (NCSR Democritos, Athens (Greece). Inst. of Nuclear Technology and Radiation Protection)

1992-01-01

29

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)

1963-01-01

30

Imaging of artificially induced vortex structures  

Energy Technology Data Exchange (ETDEWEB)

The combination of engineered pinning potentials in superconducting crystals, the detection of the liquid-solid vortex transition and the observation of the vortex structure with single vortex sensitivity allow the microscopic analysis of the response of 3D elastic systems to the presence of these potentials. In this work we review recent results obtained by a combination of those techniques studying different vortex structure induced transformations. On the one hand, we have visualized the transformation, along the vortex direction, of a bulk vortex single crystal with hexagonal symmetry into another crystal with square symmetry induced by an engineered Fe-dot lattice deposited on a surface of the vortex single crystal. On the other hand, we found an infrequent first-order phase transition where a vortex liquid under the presence of a random correlated potential (columnar defects) transforms into a vortex solid with no change of topological order.

Fasano, Yanina; Menghini, M.; Cruz, F. de la

2004-08-01

31

Imaging of artificially induced vortex structures  

International Nuclear Information System (INIS)

The combination of engineered pinning potentials in superconducting crystals, the detection of the liquid-solid vortex transition and the observation of the vortex structure with single vortex sensitivity allow the microscopic analysis of the response of 3D elastic systems to the presence of these potentials. In this work we review recent results obtained by a combination of those techniques studying different vortex structure induced transformations. On the one hand, we have visualized the transformation, along the vortex direction, of a bulk vortex single crystal with hexagonal symmetry into another crystal with square symmetry induced by an engineered Fe-dot lattice deposited on a surface of the vortex single crystal. On the other hand, we found an infrequent first-order phase transition where a vortex liquid under the presence of a random correlated potential (columnar defects) transforms into a vortex solid with no change of topological order

2004-08-01

32

Study on radioactivity and negative ion originated from a thoron artificial hot spring  

International Nuclear Information System (INIS)

To elucidate the various characteristic and their availabilities of the radioactivity and negative air ion originated from an artificial thoron hot spring, we simulated a hot spring, we simulated a hot spring condition using a monazite powder and measured the negative air ions and radioactivities in the condition. In the result, the radioactivity of the thorium series nuclide (208Tl) in monazite was 5.3 times of that of the uranium series nuclide (214Bi). For the pH(3.5-12.5) dependence of the leaching nuclides from monazite in water, the thorium series nuclides (228Ac, 212Pb) were well leached on the strong acid side because the monazite includes the rare earth element (REE) which was high ionization tendency and was substituted by the radioactive nuclide. On the other side, the uranium series nuclides (214Bi, 214Pb) leached in water were not detected because the specific activities of the uranium series nuclide are lower relative to those of the thorium series nuclide. Moreover, there were many negative air ions originated from monazite in the place within 10 cm away from the monazite surface. This is suggested that most negative ions exist within the range of the radiated ? rays. Negative air ions increased with increasing atmospheric relative humidity (35-60%). This is suggested that negative air ions stably existed in the hydration type such as O2-bar(H2O)n. Furthermore, for the hydrous rate dependence of the negative air ions originated from monazite, the negative air ions without supernatant fluid were larger than those with supernatant fluid, because ? rays ionized water on the surface of monazite. (author)

2005-09-01

33

Natural and artificial radionuclide measurements and radioactivity assessment of soil samples in eastern Sichuan province (China)  

International Nuclear Information System (INIS)

The activity concentrations of natural and artificial radionuclides were measured in the eastern region of Sichuan province (China). One hundred and ninety-three soil samples from this region were collected and analysed by high-purity germanium gamma spectrometry. The measured results show that the average radioactivity concentrations of 226Ra, 232Th, 40K and 137Cs in the soil samples are 26, 49, 440 and 6 Bq kg-1, respectively. The calculated average radium equivalent activity is 130 Bq kg-1, which is less than the recommended limit of 370 Bq kg-1. The absorbed dose rate and annual effective dose are 60 nGy h-1 and 74 ?Sv, respectively. This is the first time the absorbed dose rate in the east region of Sichuan has been mapped. Overall, the environmental radiation background is greater in the southern part of the area studied than in the northern. (authors)

2008-01-01

34

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

Energy Technology Data Exchange (ETDEWEB)

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).

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

35

Electromagnetically induced transparency on a single artificial atom  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 demon...

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

2010-01-01

36

Artificial neural networks in the evaluation of the radioactive waste drums activity  

International Nuclear Information System (INIS)

The mathematical techniques are becoming more important to solve geometry and standard identification problems. The gamma spectrometry of radioactive waste drums would be a complex solution problem. The main difficulty is the detectors calibration for this geometry; the waste is not homogeneously distributed inside the drums, therefore there are many possible combinations between the activity and the position of these radionuclides inside the drums, making the preparation of calibration standards impracticable. This work describes the development of a methodology to estimate the activity of a 200 L radioactive waste drum, as well as a mapping of the waste distribution, using Artificial Neural Network. The neural network data set entry obtaining was based on the possible detection efficiency combination with 10 sources activities varying from 0 to 74 x 103 Bq. The set up consists of a 200 L drum divided in 5 layers. Ten detectors were positioned all the way through a parallel line to the drum axis, from 15 cm of its surface. The Cesium -137 radionuclide source was used. The 50 efficiency obtained values (10 detectors and 5 layers), combined with the 10 source intensities resulted in a 100,000 lines for 15 columns matrix, with all the possible combinations of source intensity and the Cs-137 position in the 5 layers of the drum. This archive was divided in 2 parts to compose the set of training: input and target files. The MatLab 7.0 module of neural networks was used for training. The net architecture has 10 neurons in the input layer, 18 in the hidden layer and 5 in the output layer. The training algorithm was the 'traincgb' and after 300 'epoch s' the medium square error was 0.00108172. This methodology allows knowing the detection positions answers in a heterogeneous distribution of radionuclides inside a 200 L waste drum; in consequence it is possible to estimate the total activity of the drum in the training neural network limits. The results accuracy depends on the way that the waste drum is divided and to the amount of intensities that it is interpolated between the minimum and maximum limits. The use of the Artificial Neural Networks associated to Monte Carlo Method showed to be efficient in the isotopic characterization of radioactive waste drums. (authors)

2006-05-15

37

Monitoring induced denitrification in an artificial aquifer recharge system.  

Science.gov (United States)

As demands on groundwater increase, artificial recharge is becoming a common method for enhancing groundwater supply. The Llobregat River is a strategic water supply resource to the Barcelona metropolitan area (Catalonia, NE Spain). Aquifer overexploitation has leaded to both a decrease of groundwater level and seawater intrusion, with the consequent deterioration of water quality. In the middle section of the aquifer, in Sant Vicenç del Horts, decantation and infiltration ponds recharged by water from the Llobregat River (highly affected from wastewater treatment plant effluents), were installed in 2007, in the framework of the ENSAT Life+ project. At the bottom of the infiltration pond, a vegetal compost layer was installed to promote the growth of bacteria, to induce denitrification and to create favourable conditions for contaminant biodegradation. This layer consists on a mixture of compost, aquifer material, clay and iron oxide. Understanding the fate of contaminants, such as nitrate, during artificial aquifer recharge is required to evaluate the impact of artificial recharge in groundwater quality. In order to distinguish the source of nitrate and to evaluate the capability of the organic reactive layer to induce denitrification, a multi-isotopic approach coupled with hydrogeochemical data was performed. Groundwater samples, as well as river samples, were sampled during artificial and natural recharge periods. The isotopic analysis included: ?15N and ?18O of dissolved nitrate, ?34S and ?18O of dissolved sulphate, ?13C of dissolved inorganic carbon, and ?2H and ?18O of water. Dissolved nitrate isotopic composition (?15NNO3 from +9 to +21 o and ?18ONO3 from +3 to +16 ) demonstrated that heterotrophic denitrification induced by the reactive layer was taking place during the artificial recharge periods. An approximation to the extent of nitrate attenuation was calculated, showing a range between 95 and 99% or between 35 and 45%, by using the extreme literature ?N values of -4o and -22o respectively (Aravena and Robertson, 1998; Pauwels et al., 2000). Ongoing denitrification batch experiments will allow us to determine the specific nitrogen and oxygen isotopic fractionation induced by the organic reactive layer, in order to estimate more precisely the extent of denitrification during artificial aquifer recharge. These results confirmed that the reactive layer induces denitrification in the recharge ponds area, proving the usefulness of an isotopic approach to characterize water quality improvement occurring during artificial aquifer recharge. References 1. Aravena, R., Robertson, W.D., 1998. Use of multiple isotope tracers to evaluate denitrification in ground water: Study of nitrate from a large-flux septic system plume. Ground Water, 36(6): 975-982. 2. Pauwels, H., J.C., Kloppmann, W., 2000. Denitrification and mixing in a schist aquifer: Influence on water chemistry and isotopes. Chemical Geology, 168(3-4): 307-324. Acknowledgment This study was supported by the projects CGL2011-29975-C04-01 from the Spanish Government, 2009SGR-00103 from the Catalan Government and ENPI/2011/280-008 from the European Commission. Please fill in your abstract text.

Grau-Martinez, Alba; Torrentó, Clara; Folch, Albert; Domènech, Cristina; Otero, Neus; Soler, Albert

2014-05-01

38

Natural and artificial atmospheric radioactivity in aerosols collected in Barcelona (Spain)  

International Nuclear Information System (INIS)

Radioactivity in the Barcelona area is continuously being measured at the Radioactivity Analysis Laboratory of the Institute of Energy Technologies, Technical University of Catalonia, as it is part of a Spanish Sparse network for radiation monitoring. High sensitivity measurements are made in this laboratory. Airborne particulate sampling is carried out by pumping air through polypropylene filters at a flow rate of 800 m3/h. Measurements of radionuclides were carried out by ?-ray spectrometric analysis of particulate samples collected weekly. The results for the naturally occurring 7Be, 210Pb, 40K, 214Bi, 214Pb, 228Ac and 208Tl and for the artificial radionuclide 137Cs, during the period from January 2001 to December 2004, are given in this report. The aim of the present in paper is to find the underlying causes of variations of radionuclide concentrations in the air Barcelona and the correlation with season, rainfall, airborne particulate material, wind speed and wind direction. The annual average values obtained for 7Be, 210Pb and 137Cs during the investigation period were in good agreement with those measured in other countries. During the investigation period, the radionuclides 212Pb and 208Tl, 214Bi and 214Pb, 7Be and 210Pb, correlate significantly with each other. The correlation coefficients obtained were 0.99, 0.73 and 0.71 respectively with a confidence level of 99%. 7Be and 210Pb concentrations show the same seasonal variation, with a tendency for a maximum concentration during summer months. An inverse relationship, was generally observed, between the 7Be, 210Pb, 40K and 137Cs concentrations and weekly rainfall, indicating washout of the atmospheric aerosol that carries these radionuclides

2006-09-06

39

Table of nuclear reactions and subsequent radioactive dacays induced by 14-MeV neutrons  

International Nuclear Information System (INIS)

Compilation of the data on nuclear reactions and subsequent radioactive decays induced by 14-MeV neutrons is presented in tabular form for most of the isotopes available in nature and for some of the artificially-produced isotopes, including the following items: Nuclide (isotopic abundance), type of nuclear reaction, reaction Q-value, reaction product, type of decay, decay Q-value, half-life of reaction product, decay product, maximum reaction cross section, neutron energy for maximum cross section, reaction cross section for 14 MeV neutrons, saturated radioactivity induced by irradiation of a neutron flux of 1 n/cm2sec for a mol of atoms, and reference for the cross section. The mass number dependence of (n, ?), (n, 2n), (n, p), (n, d), (n, t), (n, 3He) and (n, ?) reaction cross sections for 14-MeV neutrons is given in figures to show general trends of the cross sections

1977-01-01

40

Applicability of artificial intelligence to reservoir induced earthquakes  

Science.gov (United States)

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.

Samui, Pijush; Kim, Dookie

2014-06-01

 
 
 
 
41

Radioactively induced noise in gas-sampling uranium calorimeters  

International Nuclear Information System (INIS)

The signal induced by radioactivity of a U_2_3_8 absorber in a cell of a gas-sampling uranium calorimeter was studied. By means of Campbell's theorem, the levels of the radioactively induced noise in uranium gas-sampling calorimeters was calculated. It was shown that in order to obtain similar radioactive noise performance as U-liquid argon or U-scintillator combinations, the ?-particles from the uranium must be stopped before entering the sensing volume of gas-uranium calorimeters

1982-10-28

42

Radioactivity: A Natural Phenomenon.  

Science.gov (United States)

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

Ronneau, C.

1990-01-01

43

Simulation of induced radioactivity for Heavy Ion Medical Machine  

CERN Document Server

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.

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

2013-01-01

44

Induced radioactivity in Bevatron concrete radiation shielding blocks.  

Science.gov (United States)

The Bevatron accelerated protons up to 6.2 GeV and heavy ions up to 2.1 GeV/amu. It operated from 1954 to 1993. Radioactivity was induced in some concrete radiation shielding blocks by prompt radiation. Prompt radiation is primarily neutrons and protons t...

G. C. Moeller R. J. Donahue

1994-01-01

45

Induced Radioactivity in Recovered Skylab Materials. [gamma ray spectra  

Science.gov (United States)

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

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

1980-01-01

46

Emissions induced by the process of radioactive remnants conditioning  

International Nuclear Information System (INIS)

The techniques applied in the Decontamination Dept., HDB, for conditioning radioactive primary and secondary waste induce emission of radiological and chemical pollutants. The paper explains the current common practice of emission monitoring and presents data of the plant-specific release of pollutants via the gaseous and liquid effluents pathway. Practice has shown that there have been no problems at all in keeping the emissions from operation below the regulatory maximum acceptable limits. The amounts released are so small that the effects on the environment remain at minimum level. Thus pollutant emission is not a factor restricting the processing of radioactive remnants or primary waste, even if high-level radioactive inventories are involved, if conditioning systems are designed and constructed in line with the appropriate operating data accumulated so far, and if emssion control is made a prime goal in the planning, control and monitoring of procedures and processes. (orig.)

1994-05-01

47

Human Thermoregulatory Responses during Heat Exposure After Artificially Induced Sunburn. (Reannouncement with New Availability Information).  

Science.gov (United States)

Human thermoregulatory responses during heat exposure after artificially induced sunburn. Am. J. Physiol. 262 (Regulatory Integrative Comp. Physiol. 31): R610- R616, 1992. Thermoregulatory responses in the heat (ambient temperature 49 deg C, 20% relative ...

K. B. Pandolf R. W. Gange W. A. Latzka I. H. Blank K. K. Kraning

1992-01-01

48

Induced radioactivity in patients from betatron irradiation  

International Nuclear Information System (INIS)

The ability to reconstruct the distribution of dose delivered throughout the treatment volume after each therapy fraction offers a mechanism for quality control. The activity within the irradiated volume in two pelvic irradiations showed initial rates of 120 to 285 detected events per minute. The activity detected 2 to 25 cm from the edge of the irradiated volume was 0 to 12 coincidences per minute. The average ratio of event rate outside the treatment volume to the rate within the volume, was 0.2 for these patients. In a fourth patient, an anterior pelvic field showed the following results after patient repositioning. A component with half-life of two minutes ("1"5O) was evident with initial activity of 2.7 plus or minus 0.5 x 10"3 counts per minute, and a component with half-life of 20.4 minutes ("1"1C) was determined with initial activity of 4.7 plus or minus 0.6 x 10"2 counts per minute. In experiments with rats, only in organs where blood contents were comparable in mass to the parenchyma, were large fractions of the induced activity transported from the radiation site. Biological transport appeared to the major source of background, and could constitute a significant correction in the computation of dose distribution from the activity distribution imaged by the positron camera. (U.K.)

1981-01-01

49

Radioactivity Induced by Neutrons: a Thermodynamic Approach to Radiative Capture  

Digital Repository Infrastructure Vision for European Research (DRIVER)

When Enrico Fermi discovered slow neutrons, he accounted for their great efficiency in inducing radioactivity by merely mentioning the well-known scattering cross-section between neutrons and protons. He did not refer to capture cross-section, at that early stage. It is put forward that a thermodynamic approach to neutron-proton radiative capture then widely debated might underlie his early accounts. Fermi had already met with a similar approach, and repeatedly used it.

Gregorio, Alberto

2005-01-01

50

Studying the induced radioactivity of a varian clinac 2100C/D accelerator  

International Nuclear Information System (INIS)

Objective: To Study the influences of dose, time, distance and irradiation mode on induced radioactivity by measuring a Varian Clinac 2100C/D accelerator. Methods: The induced radioactivity was measured in different dose, time, distance and irradiation mode by using of 450P model dosemeter. The results was analysed. Results: The induced radioactivity is direct ratio with dose, inverse ratio with time and distance. In different irradiation mode, the induced radioactivity is different. Conclusion: The induced radioactivity level of accelerator is related with dose, time, distance and irradiation mode. (authors)

2008-12-01

51

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)

1988-01-01

52

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

Energy Technology Data Exchange (ETDEWEB)

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 /sup 131/I 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 /sup 131/I with 808 pCi/kg wet weight, but another specimen obtained on June 6 was not contaminated by any detectable amounts of /sup 131/I. No radioactivity was detected in city water during the period monitored. Cow's milk and human milk contained, as a total of ..beta..-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 /sup 40/K. 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 /sup 131/I 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.

Kouyama, Hiroshi; Tatsunami, Shinobu; Watabe, Shoji; Hara, Masayuki; Hara, Kazumi; Nakamura, Iwao; Yago, Nagasumi

1988-03-01

53

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)

1963-01-01

54

Orofacial tumours induced in rats with radioactive cerium chloride  

International Nuclear Information System (INIS)

Fifty nine 6 week-old Sprague Dawley male rats were inoculated near the left angle of the mandibular bone with radioactive colloidal cerium. Fifty three rats presented orofacial tumours: forty-two single tumours and 11 double tumours. The survival time of animals with tumours ranged between 262 to 501 days after inoculation of cerium. Six rats died without tumours. Squamous cell carcinomas (SCC) and bone and soft tissue (BSTS) sarcomas were the predominant histological types (respectively 42 SCC and 14 (BSTS). Other types of tumours were also observed: 3 salivary adenocarcinomas, 3 tumours with double differrentiation, one ganglioneuroblastoma and one odontosarcoma. Double tumours were found in rats which had a significantly greater mean survival time, suggesting that the probability of double tumours increases with time. No correlation was found between the mean initial radioactivity and histological type of tumours, mean survival time, locoregional extension or presence of metastases. In general, the low incidence of metastases (17.3%) contrasted with a large locoregional extension. Only one out of five osteosarcomas of the mandible presented lung metastases, a low rate when compared to osteogenic osteosarcomas of the leg induced in rats by radioactive cerium (60-80% of metastases). The mean labelling index determined by autoradiographic study one hour after injection of 5.5 ?/g of tritiated thymidine was 23.7% +- 6.4% and 27.8% +- 6.8% respectively, for SCC and BSTS). These radio-induced tumours may constitute an interesting experimental model for human orofacial tumours

1979-01-01

55

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)

2014-01-01

56

Very low levels of artificial radioactivity in the environment in 2009  

International Nuclear Information System (INIS)

The 2009 edition of the annual state of the environment in France concerning radioactivity shows very low levels of radioactivity that are consistent with previous measurements. The radiological survey of 3 particular areas (Val de Loire, south-west of France and Rhone valley) has been made through several measurement campaigns that have involved for each area the recovery of between 100 to 200 samples in the different segments of the environment. This radiological state will be a standard for the area concerned. The 2009 edition reports also the radiological surveys of 3 ancient industrial sites: detection of Thorium 232 on the site of the Orflam-Plast company at Pargny-sur-Saulx (Marne department), detection of Carbon 14 around the ancient laboratory of the Isotopchim company near Forcalquier (Alpes de Haute Provence department) and radium contamination on the ancient site of the Satchi company at Charvet (Seine Saint-Denis department). (A.C.)

2009-01-00

57

Anthrax toxin-induced rupture of artificial lipid bilayer membranes.  

Science.gov (United States)

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. PMID:23947891

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

2013-08-14

58

NATURAL AND ARTIFICIAL RADIOACTIVITY IN BULGARIAN SOILS ALONG THE DANUBE RIVER  

Directory of Open Access Journals (Sweden)

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.

I YORDANOVA

2005-07-01

59

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

Science.gov (United States)

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

Faghihi, R; Mehdizadeh, S; Sina, S

2011-04-01

60

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)

1985-01-01

 
 
 
 
61

Transport and dispersion of artificial radioactivity in the Arctic Ocean - Model studies and observations -  

International Nuclear Information System (INIS)

The Arctic Ocean and the adjacent shelf regions are subject to growing concern because of increasing environmental problems. The most crucial problem arises probably from the dumping of nuclear waste in the Barents and the Kara Sea. But also the great Siberian rivers Ob and Yenisei which drain huge land areas and industrial zones may contribute to the input of pollutants into the Arctic environment. First results of a joint project are described which combines numerical model studies and experimental field work in order to investigate the potential pathways and dispersion of radioactive contaminants in the Arctic Ocean. (author)

1996-10-07

62

Transport and dispersion of artificial radioactivity in the Arctic Ocean - Model studies and observations -  

Energy Technology Data Exchange (ETDEWEB)

The Arctic Ocean and the adjacent shelf regions are subject to growing concern because of increasing environmental problems. The most crucial problem arises probably from the dumping of nuclear waste in the Barents and the Kara Sea. But also the great Siberian rivers Ob and Yenisei which drain huge land areas and industrial zones may contribute to the input of pollutants into the Arctic environment. First results of a joint project are described which combines numerical model studies and experimental field work in order to investigate the potential pathways and dispersion of radioactive contaminants in the Arctic Ocean. (author) 16 refs.

Nies, H.; Bahe, C.; Karcher, M.J.; Kleine, E. [Bundesamt fuer Seeschiffahrt und Hydrographie, Hamburg (Germany); Dethleff, D. [Research Center for Marine Geosciences, Kiel (Germany); Harms, I.H. [Hamburg Univ. (Germany). Inst. fuer Meereskunde

1997-12-31

63

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)

1975-01-01

64

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

65

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, "1"0"6Ru and from atmospheric fall out, "1"3"7Cs 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

1985-01-01

66

Using radioactivity  

International Nuclear Information System (INIS)

The leaflet discusses the following: radioactivity; radioisotopes; uses of ionising radiations; radioactivity from (a) naturally occurring radioactive elements, and (b) artificially produced radioisotopes; uses of radioactivity in medicine, (a) clinical diagnostic, (b) therapeutic (c) sterilization of medical equipment and materials; environmental uses as tracers; industrial applications, e.g. tracers and radiography; ensuring safety. (U.K.)

1982-01-01

67

Induced radioactivity of the IHEP proton synchrotron beam extraction equipment  

International Nuclear Information System (INIS)

The measurement results of induced radioactivity of the beam extraction equipment during 1972-1978 are presented. All the values are given to the moment of the accelerator stop. The experimental data permits to predict further possible variations of the induced radioactivity levels of the equipment. Given are the measures required for reduction of the accelerator equipment irradiation, which are the following: 1) compensation of residual distortion of a closed beam orbit in the course of the induction system operation; 2) limitation of the intensity of drop on the internal targets up to the <=5x10"1"1 protons per target level over a cycle; 3) putting into operation the program control system for the duration of a current pulse of a linear accelerator to minimize the beam residues at the 70 GeV energy during physical experiments; 4) construction of the system of beam interception and cutting-off to ensure effective energy suppression of uncontrolled beam residues and localization of their radiation effect; 5) extraction of a high-energy beam out of the accelerator during the experiments (e.g., into the neutrino channel for apparatus adjusting) instead of its dropping on the interceptor-target; 6) beam orbit controlling in the case of multiturn injection into the accelerator

68

Induced radioactivity in and around high-energy particle accelerators.  

Science.gov (United States)

Particle accelerators and their surroundings are locations of residual radioactivity production that is induced by the interaction of high-energy particles with matter. This paper gives an overview of the principles of activation caused at proton accelerators, which are the main machines operated at Conseil Européen pour la Recherche Nucléaire. It describes the parameters defining radio-nuclide production caused by beam losses. The second part of the paper concentrates on the analytic calculation of activation and the Monte Carlo approach as it is implemented in the FLUKA code. Techniques used to obtain, on the one hand, estimates of radioactivity in Becquerel and, on the other hand, residual dose rates caused by the activated material are discussed. The last part of the paper focuses on experiments that allow for benchmarking FLUKA activation calculations and on simulations used to predict activation in and around high-energy proton machines. In that respect, the paper addresses the residual dose rate that will be induced by proton-proton collisions at an energy of two times 7 TeV in and around the Compact Muon Solenoid (CMS) detector. Besides activation of solid materials, the air activation expected in the CMS cavern caused by this beam operation is also discussed. PMID:21697180

Vincke, Helmut; Theis, Chris; Roesler, Stefan

2011-07-01

69

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

1990-01-01

70

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)

2002-01-01

71

Evaluation of induced radioactivity in 10 MeV-electron irradiated spices, (1)  

International Nuclear Information System (INIS)

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 ?-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 H50 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 40K contained in the samples. (author)

1994-02-01

72

Radioactivity  

... Radioactive isotopes of iodine, which undergo beta-decay, can build up in the thyroid gland and can cause thyroid cancer. Attempts to prevent this involve distributing pills that include nonradioactive iodine-127 and which flood the thyroid, preventing uptake of radioactive iodine. For one-off doses, ...

73

Radiation Sialadenitis Induced by High-dose Radioactive Iodine Therapy  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2010-06-15

74

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

1994-01-01

75

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.)

2002-01-01

76

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 invento...

Li, Y.; Chen, G.; Tang, C.; Zhou, G.; Zheng, L.

2012-01-01

77

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 la...

Li, Y. G.; Chen, G. Q.; Tang, C.; Zhou, G. Y.; Fan, Y. N.

2012-01-01

78

Electromagnetically Induced Transparency Using a Artificial Molecule in Circuit Quantum Electrodynamics  

Directory of Open Access Journals (Sweden)

Full Text Available Electromagnetically induced transparency (EIT having wide applications in quantum optics and nonlinear optics is explored ordinarily in various atomic systems. In this paper we present a theoretical study of EIT using supercon- ducting circuit with a V-type artificial molecule constructed by two Josephson charge qubits coupled each other through a large capacitor. In our theoretical model we make a steady state approximation and obtain the analytical expressions of the complex susceptibility for the artificial system via the density matrix formalism. The complex susceptibility has additional dependence on the qubit parameters and hence can be tuned to a certain extent.

Hai-Chao Li

2013-06-01

79

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.)

1981-01-01

80

Products of an Artificially Induced Hydrothermal System at Yucca Mountain  

International Nuclear Information System (INIS)

Studies of mineral deposition in the recent geologic past at Yucca Mountain, Nevada, address competing hypotheses of hydrothermal alteration and deposition from percolating groundwater. The secondary minerals being studied are calcite-opal deposits in fractures and lithophysal cavities of ash-flow tuffs exposed in the Exploratory Studies Facility (ESF), a 7.7-km tunnel excavated by the Yucca Mountain Site Characterization Project within Yucca Mountain. An underground field test in the ESF provided information about the minerals deposited by a short-lived artificial hydrothermal system and an opportunity for comparison of test products with the natural secondary minerals. The heating phase lasted nine months, followed by a nine-month cooling period. Natural pore fluids were the only source of water during the thermal test. Condensation and reflux of water driven away from the heater produced fluid flow in certain fractures and intersecting boreholes. The mineralogic products of the thermal test are calcite-gypsum aggregates of less than 4-micrometer crystals and amorphous silica as glassy scale less than 0.2 mm thick and as mounds of tubules with diameters less than 0.7 micrometers. The minute crystal sizes of calcite and gypsum from the field test are very different from the predominantly coarser calcite crystals (up to cm scale) in natural secondary-mineral deposits at the site. The complex micrometer-scale textures of the amorphous silica differ from the simple forms of opal spherules and coatings in the natural deposits, even though some natural spherules are as small as 1 micrometer. These differences suggest that the natural minerals, especially if they were of hydrothermal origin, may have developed coarser or simpler forms during subsequent episodes of dissolution and redeposition. The presence of gypsum among the test products and its absence from the natural secondary-mineral assemblage may indicate a higher degree of evaporation during the test than during the deposition of natural calcite-opal deposits

2000-01-01

 
 
 
 
81

Artificially induced sporadic E. Scientific interim repts. 1--2  

Energy Technology Data Exchange (ETDEWEB)

Ionospheric disturbances induced by chemical releases from high-altitude rockets were monitored by Digisonde and Doppler-drift observations. The ionogram recordings provide the basic information on the ionospheric layers in terms of vertical electron density profiles. The Doppler-drift observations lead to the determination of the ionospheric structure and drifts. (GRA)

Bibl, K.; Reinisch, B.W.

1975-04-01

82

Scoping estimates of the LDEF satellite induced radioactivity  

Science.gov (United States)

The Long Duration Exposure Facility (LDEF) satellite was recovered after almost six years in space. It was well-instrumented with ionizing radiation dosimeters, including thermoluminescent dosimeters, plastic nuclear track detectors, and a variety of metal foil samples for measuring nuclear activation products. The extensive LDEF radiation measurements provide the type of radiation environments and effects data needed to evaluate and help resolve uncertainties in present radiation models and calculational methods. A calculational program was established to aid in LDEF data interpretation and to utilize LDEF data for assessing the accuracy of current models. A summary of the calculational approach is presented. The purpose of the reported calculations is to obtain a general indication of: (1) the importance of different space radiation sources (trapped, galactic, and albedo protons, and albedo neutrons); (2) the importance of secondary particles; and (3) the spatial dependence of the radiation environments and effects expected within the spacecraft. The calculational method uses the High Energy Transport Code (HETC) to estimate the importance of different sources and secondary particles in terms of fluence, absorbed dose in tissue and silicon, and induced radioactivity as a function of depth in aluminum.

Armstrong, Tony W.; Colborn, B. L.

1990-01-01

83

Disturbances of immunological homeostasis induced by radioactive iodine agents  

International Nuclear Information System (INIS)

(CBAxC57B1/6)F_1 mice were injected with "1"2"5I and "1"3"1I-sodium iodide at a dose of 5.74x10"4 Bq/g. For a long time after such treatment the animals manifested an increased level of spleen cells humoral immune response to a foreign antigen (sheep erythrocytes). The autoreactivity of spleen and lymph node lymphocytes to autologous erythrocytes was also elevated. At the same time the selective migration of "5"1Cr-labeled spleen lymphocytes to the peripheral lymphoid organs was suppressed. The use of a model system of adoptive cell transfer revealed an increase in the functional activity of cells suppressing a humoral response in mice treated with radiopharmaceuticals. The most pronounced disturbances of immunological reactivity in mice took place 6 mos. after the beginning of the experiment. The results obtained indicated that mechanisms of immune response regulation played a certain role in disturbances of immunological homeostasis induced by radioactive iodine agents

1986-01-01

84

Low-energy radioactive ion beam induced nuclear reactions  

International Nuclear Information System (INIS)

Low-energy post-accelerated radioactive ion beams have been used to study nuclear reactions addressing important nuclear structure and nuclear astrophysics questions. A high-granularity, large-solid-angle silicon strip detector array has been used to account for the low reaction products' yields. First experiments using a 6He beam on thin 12C targets show the feasibility of direct reaction studies with good angular resolution and a detection limit in access of 0.1 mb sr-1 cross sections. The measurement of the six ?-decay channel in a 13N-induced reaction on a 11B target shows the capabilities of this experimental technique even for sophisticated reaction studies. The study of stellar properties in ground-based experiments, in particular break-out reactions from the hot-CNO, i.e. 15O(?, ?)19Ne, can be pursued using these beams. Experiments are being performed to study these reactions by measurement of d(18Ne, p)19Ne*(?)15O and ?(18Ne, p), which might provide an alternative breakout route. (author)

1998-08-01

85

Artificial sweeteners produce the counterintuitive effect of inducing metabolic derangements.  

Science.gov (United States)

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

Swithers, Susan E

2013-09-01

86

Study of genetic effects in plants induced by natural radioactivity in southwest France  

International Nuclear Information System (INIS)

Southwest France has a number of radioactive areas with an average background rate ranging between 1 and 30 ?rads/h. Reference response curves were established for the ?1+/?1 ?2+/?2 system of tobacco in the artificially radioactive site of the French Atomic Energy Commission at Cadarache (137Cs); the response was found to be linear between 10 ?rads/h (background) and 1 rad/h. The response of the system, together with that of the waxy system in Barley, was then studied over natural uranous sites in the Permian Basin of Lodeve (Herault) and the area of Lagravette

1978-04-28

87

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

2006-01-01

88

Laboratory Observations of Wave-Induced Radial Transport within an "Artificial Radiation Belt"  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Wave-induced radial transport of energetic electrons has been observed in a laboratory terrella. In the experiment, electron-cyclotron-resonance heating (ECRH) is used to create a localized population of trapped energetic electrons (1 keV < Eh < 50 keV) within a low-density discharge which we refer to as an "artificial radiation belt." As the intensity of the radiation belt increases, quasiperiodic bursts of drift-resonant fluctuations, ? ? ?dh, are excited. The frequency spectrum...

1997-01-01

89

Artificial UV-B induced changes in pigmentation of marine diatom Coscinodiscus gigas.  

Science.gov (United States)

In vitro studies in marine diatom Coscinodiscus gigas revealed that artificial UV-B radiation (313 nm) at a dose level of 0.4W m(-2) for a continuous period of 3 hours in a UV treatment chamber caused disbursement of chromatophores from their normal loci and resulted in clumping / aggregation of chromatophores exhibiting a phenomenon called UV-B induced syntrophism. It is also understood that such clumping could cause only insignificant reduction in photosynthetic oxygen release. PMID:17915774

Yogamoorthi, A

2007-04-01

90

Calculation of the Radioactivity Induced in PWR Cluster Control Rods with the ORIGEN and CASMO Codes.  

Science.gov (United States)

The radioactivity induced in PWR cluster control rods during reactor operation has been calculated using the computer programme ORIGEN. Neutron fluxes and spectrum conditions as well as the strongly shielded cross sections for the absorber materials Ag, I...

K. Ekberg

1980-01-01

91

Evaluation of radioactivity induced by patient-specific devices in proton therapy  

Energy Technology Data Exchange (ETDEWEB)

Estimating the radioactivity induced by patient-specific devices installed near the patient skin is important, because patients are directly exposed during the treatment. This study evaluated the radioactivity induced by a brass collimator and a PMMA range compensator in a proton beam and identified the radionuclides produced by nuclear interactions with the proton beam and with the patient-specific devices. The total dose rate depended on the radionuclides, which had short decay times and 1 hour later their activities reach about one-fiftieth of the initial values in the cases of both PMMA and brass. Although the radioactivity induced by proton therapy can affect patients during the radiotherapy, the total radiation dose is much smaller than the prescribed dose for cancer treatment, and the treatment time is very short. Therefore, the radioactivity induced by patient-specific devices should be negligible.

Lee, Sang Hoon; Cho, Sung Koo; You, Seung Hoon; Shin, Dong Ho; Park, Sung Yong; Lee, Se Byeong [National Cancer Center, Goyang (Korea, Republic of); Kwak, Jung Won [Asan Medical Center, Seoul (Korea, Republic of); Woo, Jong Kwan [Jeju National University, Jeju (Korea, Republic of); Kim, Dae Hyun [Catholic University, Seoul (Korea, Republic of)

2012-01-15

92

Natural and induced radioactivity in surroundings of the NPP Mochovce. Part: Natural Radioactivity  

International Nuclear Information System (INIS)

The aim of this paper was the observation of the influences of the turning on of the NPP Mochovce into the work, to find out the situation of the environment in its surroundings, so the content of the radionuclides before the beginning of its operation. In this paper, there was areal evaluated the content of the natural radionuclides potassium, uranium, thorium, of total radioactivity, of dose rate and of radon risk of the minerals, as well as point evaluation of natural radioactivity of the waters, so the content of the Unat, radium-226, radon-222 in the waters. The measurement of the natural radioactivity of the minerals were realized on the area of 480 km2 in the scale 1:10000 and they were treated into the maps in the scale 1:25000. The measured values are given in the tables

1997-10-21

93

Radioactivity in spruces  

International Nuclear Information System (INIS)

Some specimens of spruces have been examined by gamma spectroscopy for their amount of natural and induced radioactivity. Besides the natural radionuclides K-40 and Be-7, several gamma-ray emitters of the natural decay chains have been detected, and Cs-137. The activity concentration of the latter, artificial radionuclide, has been found to be very low in comparison with the concentration of all the natural gamma emitters measured. (orig./PW)

1986-06-07

94

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

Science.gov (United States)

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.

El Haddad, J.; Villot-Kadri, M.; Ismaël, A.; Gallou, G.; Michel, K.; Bruyère, D.; Laperche, V.; Canioni, L.; Bousquet, B.

2013-01-01

95

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)

1988-01-01

96

Radioactivity of Tobacco Leaves and Radiation Dose Induced from Smoking  

Directory of Open Access Journals (Sweden)

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.

Constantin Papastefanou

2009-02-01

97

Evaluation of induced radioactivity in 10 MeV electron-irradiated spices  

Energy Technology Data Exchange (ETDEWEB)

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.).

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

98

Evaluation of induced radioactivity in 10 MeV electron-irradiated spices  

International Nuclear Information System (INIS)

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 H50 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 40K contained in the samples. (J.P.N.)

1993-10-01

99

Measurements of induced radioactivity in electron- and photon-irradiated beef  

International Nuclear Information System (INIS)

Samples of beef were irradiated with electrons of approx. 10-and 13.5- MeV energies or with "6"0Co ?-ray photons (1.17 and 1.33 MeV). Induced radioactivity was measured with a ?-ray spectrometer, consisting of a Ge(Li) detector and a multichannel analyzer. No induced radioactivity could be detected in the photon-irradiated samples; also for 10-MeV electrons the activity was below the detection limit. The irradiation by 13.5-MeV electrons, however, resulted in measurable radioactivity and the amount of "1"3N-activity was in agreement with previously calculated values. These measurements confirm previous conclusions that irradiation of food with electrons at 10 MeV or even at 13.5 Mev does not constitute any health risk due to radioactivity. Part of the induced radioactivity from 13.5-MeV electron irradiation is due to neutron capture, and the results suggest that several neutron sources contribute to the measured radioactivity. (author)

1987-01-01

100

Neutron induced reactions on radioactive beryllium and argon isotopes  

CERN Document Server

The preparation of radioactive 10Be, 37Ar and 39Ar samples is discussed. Investigation of the 10Be(n_th,gamma)11Be, 37Ar(n_th,alpha)34S, 37Ar(n_th,p)37Cl and 39Ar(n_th,alpha)36S reactions is reported, and resonances in the 37Ar(n,alpha)34S reaction have been observed and analysed.

Wagemans, C; Wagemans, J; Köster, U; Loiselet, M; Gaelens, M; Geltenbort, P

2001-01-01

 
 
 
 
101

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.)

1978-01-01

102

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

1997-08-25

103

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

Energy Technology Data Exchange (ETDEWEB)

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).

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

104

Measuring of induced radioactivity of the HE megatile on IREN at JINR.  

CERN Document Server

Results of measurement of the induced radioactivity caused by neutrons for a segment of a multi sectional scintillation detector (megatile) are presented. Two endcap sampling calorimeters (HE) are parts of the hadron calorimeter (HCAL) of experimental setup CMS. Each HE consists of 648 megatiles. Irradiation of a section of the megatile by neutrons has been performed as neutron activation is the main source of induced radioactivity. Irradiation of a segment of the megatile was carried out on IREN - the JINR neutron source facility. The HE will be accessible to humans after a suitable period of cool down.

Afanasiev, Sergey; Borzakov, S.B; Golutvin, Igor; Igamkulov, Z.A; Malakhov, Alexander; Moisenz, Petr; Pogodaev, G.N; Pyataev, V.G; Sedyshev, P.V; Shvetsov, V.N; Smirnov, Vitaly

2014-01-01

105

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

Directory of Open Access Journals (Sweden)

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%.

S. Lee

2006-01-01

106

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

1984-01-01

107

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)

1960-01-11

108

Application of induced seismicity to radioactive waste management programmes  

International Nuclear Information System (INIS)

Induced seismicity can make a unique contribution to our understanding of rock mass response due to excavation and thermal-induced loads, during the site characterization and performance monitoring of a nuclear waste repository. Field data, with supplementary laboratory studies, are presented to show how induced high-frequency acoustic emission/microseismicity (AE/MS) can be used as a tool for passive volumetric remote sensing of failure processes. Case studies are described using results from experiments carried out at Atomic Energy of Canada Ltd's (AECL) Underground Research Laboratory (URL). This site has been operated for the last ten years to investigate the concept of safe disposal of nuclear waste fuel in a granitic rock mass at 420 m depth. (Author)

1996-01-01

109

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)

2005-01-01

110

Predicting induced radioactivity for the accelerator operations at the Taiwan Photon Source.  

Science.gov (United States)

This study investigates the characteristics of induced radioactivity due to the operations of a 3-GeV electron accelerator at the Taiwan Photon Source (TPS). According to the beam loss analysis, the authors set two representative irradiation conditions for the activation analysis. The FLUKA Monte Carlo code has been used to predict the isotope inventories, residual activities, and remanent dose rates as a function of time. The calculation model itself is simple but conservative for the evaluation of induced radioactivity in a light source facility. This study highlights the importance of beam loss scenarios and demonstrates the great advantage of using FLUKA in comparing the predicted radioactivity with corresponding regulatory limits. The calculated results lead to the conclusion that, due to fairly low electron consumption, the radioactivity induced in the accelerator components and surrounding concrete walls of the TPS is rather moderate and manageable, while the possible activation of air and cooling water in the tunnel and their environmental releases are negligible. PMID:21068597

Sheu, R J; Jiang, S H

2010-12-01

111

Induced radioactivity of LDEF materials and structural components  

Science.gov (United States)

We present an overview of the Long Duration Exposure Facility (LDEF) induced activation measurements. The LDEF, which was gravity-gradient stabilized, was exposed to the low Earth orbit (LEO) radiation environment over a 5.8 year period. Retrieved activation samples and structural components from the spacecraft were analyzed with low and ultra-low background HPGe gamma spectrometry at several national facilities. This allowed a very sensitive measurement of long-lived radionuclides produced by proton- and neutron-induced reactions in the time-dependent, non-isotropic LEO environment. A summary of major findings from this study is given that consists of directionally dependent activation, depth profiles, thermal neutron activation, and surface beryllium-7 deposition from the upper atmosphere. We also describe a database of these measurements that has been prepared for use in testing radiation environmental models and spacecraft design.

Harmon, B. A.; Laird, C. E.; Fishman, G. J.; Parnell, T. A.; Camp, D. C.; Frederick, C. E.; Hurley, D. L.; Lindstrom, D. J.; Moss, C. E.; Reedy, R. C.; Reeves, J. H.; Smith, A. R.; Winn, W. G.; Benton, E. V.

1996-01-01

112

Ability of use of radiation monitoring networks on detection of natural and artificial radioactivity in the environment  

International Nuclear Information System (INIS)

In the paper there are analysed and compared regional and local early warning radiation monitoring systems. The second generation of early warning systems comprises at least one air filter unit in order to enrich airborne radioactivity, in addition to the traditional dose rate measurement. Two possible implementations of these devices are the systems with moving filter band(s) and with static filter(s), respectively. Model systems are compared and evaluated by virtue of their response to two critical cases: the appearance of an instantaneous contaminant originating from the vicinity of the device and the slow bild-up of and a contaminant arriving from a long distance. Structure and components of sampling, data acquisition and data evaluation procedures are compared according to the requirements of early warning systems. (author)

2007-10-01

113

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)

2006-02-01

114

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)

2004-10-25

115

Results of concentration measurements of artificial radioactive aerosols in the lower atmosphere; Resultats des mesures de concentration, dans la basse atmosphere, des aerosols radioactifs artificiels  

Energy Technology Data Exchange (ETDEWEB)

This report gives the results of the measurements of artificial gross-{beta}-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) [French] Ce rapport contient les resultats des mesures de radioactivite {beta} globale d'origine artificielle des aerosols dans la basse atmosphere, effectuees conjointement par le Service d'Electronique Physique du Departement d'Electronique et le Laboratoire de Physique de l'Atmosphere de la Faculte des Sciences de Paris. Les mesures ont commence en septembre 1956 et ont ete poursuivies dans un nombre croissant de stations, tant en France que dans le reste du monde. Le present rapport s'arrete a la fin aout 1961, c'est-a-dire au moment de la reprise des essais nucleaires. Apres avoir rappele la constitution et les proprietes des aerosols radioactifs presents dans l'atmosphere, les auteurs indiquent les methodes de mesure utilisees, evaluent leur precision et discutent les differents aspects des resultats de leurs mesures. (auteurs)

Ardouin, B.; Jehanno, C.; Labeyrie, J.; Lambert, G.; Tanaevsky, O.; Vassy, E. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

1963-07-01

116

Unfolding Spectral Patterns Induced by Artificial Weakly Relativistic Beam in the Ionosphere  

Science.gov (United States)

Very diverse set of HF spectra was induced by artificial electron beam injections from the APEX satellite. The spectra were registered in unplanned absence of Xe+ plasma jet, aimed to protect spacecraft against overcharging. Acceleration voltage of 10kV, current modulation frequency ranging from d.c. to 250kHz, low divergence of 4deg, slow variations of pitch angle and maximum instantaneous intensity of 0.15A characterize electron beam. In these time intervals a radiospectrometer operated in a survey mode providing one spectrum every 2s or 8s. The single spectrum was measured in 1s with an equally spaced mesh of 200 frequencies starting from 100kHz with a step of 50kHz. The receiver with a bandwidth of 15 kHz was connected to a tubular dipole antenna having half length of 7.5m. Total number of 400 spectra is not impressive but they are characterized by reproducibility of spectral patterns. From reproducibility or slow evolution of the spectra, it may be inferred that distinct interactions prevail for some ranges of ambient electron gyro (fc) and plasma (fn) frequencies, injection pitch angles and beam intensities. It appears that discrete emission can be identified at least on ambient plasma frequency or ambient upper hybrid frequency (fu). One class of arguments supporting such identifications is provided by interrelation between spectral signatures of local plasma density in passive mode and beam induced spectra. Another class of arguments is provided by interrelations between spectral structures induced by electron beam. For large angles of e-beam injection, electromagnetic character of gyroharmonics radiation from weakly relativistic beam and emissions at harmonics of upper hybrid frequency were reported. In this presentation we extend investigation to pitch angle dependence of electron beam induced spectra. Few examples of spectra induced by very weak beam and by strong beam draw attention to relevance of its intensity. We estimate relevance of propagation for spectral bandwidth with ray tracing of inferred emission modes. The diversity and reproducibility of spectral patterns support viability of simulation of astrophysical plasma in controlled electron beam-space plasma experiments. Narrow single mode emission induced in weak beam regime can be used for monitoring of ambient plasma density.

Kiraga, Arek

117

Unfolding spectra induced by artificial weakly relativistic electron beam in the ionosphere  

Science.gov (United States)

Very diverse set of HF spectra was induced by artificial electron beam injections from the APEX satellite The spectra were registered in unplanned absence of Xe plasma jet aimed to protect spacecraft against overcharging Acceleration voltage of 10kV current modulation frequency ranging from d c to 250kHz low divergence of 4deg slow variations of pitch angle and maximum instantaneous intensity of 0 15A characterize electron beam In these time intervals a radiospectrometer operated in a survey mode providing one spectrum every 2s or 8s The single spectrum was measured in 1s with an equally spaced mesh of 200 frequencies starting from 100kHz with a step of 50kHz The receiver with a bandwidth of 15 kHz was connected to a tubular dipole antenna having half length of 7 5m Spectra are characterized by reproducibility of spectral patterns From reproducibility or slow evolution of the spectra it may be inferred that distinct interactions prevail for some ranges of ambient electron gyro and plasma frequencies injection pitch angles and beam intensities It appears that discrete emission can be identified at least on ambient plasma frequency or ambient upper hybrid frequency One class of arguments supporting such identifications is provided by interrelation between spectral signatures of local plasma density in passive mode and beam induced spectra Another class of arguments is provided by interrelations between spectral structures induced by electron beam For large angles of e-beam injection electromagnetic character of gyro harmonics radiation from weakly

Kiraga, A.

118

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)

2006-01-01

119

Measurement of Natural and Artificial Radioactivity in Soil at Some Selected Thanas around the TRIGA Mark-II Research Reactor at AERE, Savar, Dhaka  

Directory of Open Access Journals (Sweden)

Full Text Available The activity concentration of natural and fallout radionuclides in the soil at some selected Thanas around the TRIGA Mark-II Research Reactor at Atomic Energy Research Establishment (AERE, Savar, Dhaka were measured by using a high purity germanium detector (HPGe. The study revealed that only natural radionuclides were present in the samples and no trace of any artificial radionuclide was found. The average activity concentration of 238U, 232Th and 40K were found to be 37.8 ± 5.6 Bq.kg-1, 58.2 ± 11.0 Bq.kg-1 and 790.8 ± 153.4 Bq.kg-1 respectively. The radium equivalent activity (Req, absorbed dose rate (D, external radiation hazard index (Hex and internal radiation hazard index (Hin were also calculated to find out the probable radiological hazard of the natural radioactivity.

Shawpan C. Sarkar

2011-12-01

120

Effects of rainwater-harvesting-induced artificial recharge on the groundwater of wells in Rajasthan, India  

Science.gov (United States)

In light of the increasing deterioration of groundwater supplies in Rajasthan, India, rainwater harvesting practices in southern Rajasthan were studied to determine the effects of artificially recharged groundwater on the supply and quality of local groundwater. A physical and geochemical investigation utilizing environmental tracers (?18O and Cl-), groundwater level and groundwater quality measurements, and geological surveys was conducted with two objectives: (1) to quantify the proportion of artificially recharged groundwater in wells located near rainwater harvesting structures and (2) to examine potential effects of artificial recharge on the quality of groundwater in these wells. A geochemical mixing model revealed that the proportion of artificial recharge in these wells ranged from 0 to 75%. Groundwater tracer, water table, and geological data provided evidence of complex groundwater flow and were used to explain the spatial distribution of artificial recharge. Furthermore, wells receiving artificial recharge had improved groundwater quality. Statistical analysis revealed a significant difference between the water quality in these wells and wells determined not to receive artificial recharge, for electrical conductivity and SO{4/-}. The findings from this study provide quantitative evidence that rainwater harvesting structures in southern Rajasthan influence the groundwater supply and quality of nearby wells by artificially recharging local groundwater.

Stiefel, John M.; Melesse, Assefa M.; McClain, Michael E.; Price, René M.; Anderson, Elizabeth P.; Chauhan, Narendra K.

2009-12-01

 
 
 
 
121

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

CERN Document Server

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.

Cesa, A

2013-01-01

122

Laser-induced artificial defects (LIADs): towards the control of the spatiotemporal dynamics in spin transition materials.  

Science.gov (United States)

Micrometer-sized defects, induced by laser ablation, radically change the spatiotemporal dynamics of a first-order structural phase transition, in this case of a spin crossover material. This type of "domain engineering" is thus based on artificial defects, such as that in the image, which can serve either as nucleation sites or as pinning sites. The subsequent growth of the nucleated domains can also be guided to some extent. PMID:22488971

Bedoui, Salma; Lopes, Manuel; Zheng, Sipeng; Bonnet, Sylvestre; Molnár, Gábor; Bousseksou, Azzedine

2012-05-01

123

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 mornin...

2002-01-01

124

Thermally induced magnetic relaxation in building blocks of artificial kagome spin ice  

Science.gov (United States)

We have performed a study of thermally driven magnetic relaxation in building blocks of artificial kagome spin ice. For room-temperature measurements, we observe that low-energy states are accessed with high efficiency, particularly in structures with strong dipolar coupling and with low thicknesses. With carefully tuned heating experiments, we demonstrate how thermally active artificial spin ice systems relax magnetically from higher-energy states and eventually fall into low-energy states. The methods applied in our work offer the possibility to observe the thermodynamics of artificial spin ice systems in real space and time, and provide a way to directly investigate the nature of complex stochastic processes.

Farhan, Alan; Kleibert, Armin; Derlet, Peter M.; Anghinolfi, Luca; Balan, Ana; Chopdekar, Rajesh V.; Wyss, Marcus; Gliga, Sebastian; Nolting, Frithjof; Heyderman, Laura J.

2014-06-01

125

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)

2001-01-01

126

Environmental radioactivity. Measurement and monitoring; Umweltradioaktivitaet. Messung und Ueberwachung  

Energy Technology Data Exchange (ETDEWEB)

The contribution on environmental radioactivity covers the following issues: natural and artificial radioactivity; continuous monitoring of radioactivity; monitoring authorities and measurement; radioactivity in the living environment; radioactivity in food and feeding stuff; radioactivity of game meat and wild-growing mushrooms; radioactivity in mines; radioactivity in the research center Rossendorf.

NONE

2009-11-15

127

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 10"3 ?Ci/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

1980-01-01

128

Dependence of neutron-induced radioactivity in fusion reactors on geometric design parameters  

Energy Technology Data Exchange (ETDEWEB)

Although the neutron-induced activation in a fusion reactor is a non-linear problem whose solution requires the use of neutron transport codes and neutron activation and decay codes, a number of simple arguments can be made which give useful scaling laws for the total radioactivity in a fusion reactor. Because these laws rely heavily on assumptions of linearity and the smallness of second-order effects, we have compared them to the results of computer experiments designed to investigate their validity over the range of operating parameters typical of fusion reactors.

Lasche, G.P.; Blink, J.A.

1983-01-01

129

The artificial surface-induced whole blood inflammatory reaction revealed by increases in a series of chemokines and growth factors is largely complement dependent  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Exposing blood to an artificial surface results in a systemic inflammatory response, including cytokine release and complement activation. We studied the artificial surface-induced inflammation in human whole blood using an extensive panel of inflammatory mediators including proinflammatory cytokines, chemokines and growth-factors and investigated the role of the complement system in the induction of this response. Using multiplex technology, 27 different inflammatory mediators were measured ...

Lappega?rd, K. T.; Bergseth, G.; Riesenfeld, J.; Pharo, A.; Magotti, P.; Lambris, J. D.; Mollnes, T. E.

2008-01-01

130

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

Science.gov (United States)

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 (P<0.0001). In a nutshell, ozone enhanced the remineralizing potential of nanohydroxyapatite, and laser induced fluorescence was found to be effective in assessing the surface mineral changes in enamel. Ozone can be considered an effective agent in reversing the initial enamel caries there by preventing the tooth from entering into the repetitive restorative cycle.

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

2014-02-01

131

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

CERN Multimedia

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

Herrera-Martínez, Adonai

132

Filtration and ventilation of induced radioactive gases at the ETL linac  

Energy Technology Data Exchange (ETDEWEB)

The facilities of filtration and ventilation of induced radioactive gases were installed in the ETL linac building in 1980. The yield estimation of /sup 15/O, /sup 13/N, O/sub 3/ and NO/sub X/ described here was done for the design of the facilities used for filtration and ventilation of these gases. At the pulsed injection for the storage ring and at the measurement of electron energy spectra, a few part of the electron beam is scattered and spilled from the vacuum beam duct and yields most of them in the accelerator room. Even at the most serious conditions, no cooling time enables reducing their density less than a level of the legally permissible density except of the axiliary shielding area near the target in each experimental room.

Kimura, M.; Tomimasu, T.; Mikado, T.; Sakai, M.; Sakamoto, F.

1987-10-01

133

Induced radioactivity of commercial isotropic graphites for high heat flux tiles  

Science.gov (United States)

It used as the plasma-facing material in the next-generation fusion devices, graphite will induce radioactivity in impurities in the graphite. This study was carried out to evaluate the amount of radiologically significant impurities in commercial isotropic graphite tiles. Special attention is given to the benefits of purification by halogen treatment. Graphite tiles from seven Japanese companies were irradiated in JMTR to neutron fluences up to 7.7 × 10 24 n/m 2 fast ( E > 0.1 MeV) and 1 × 10 25 n/m 2 thermal ( E elements and rare earth elements. The origins of these impurities are suggested and the effects of halogen treatment on the reduction of these impurities are analyzed.

Shikama, T.; Kayano, H.; Fujitsuka, M.; Tanabe, T.

1991-03-01

134

Measurement of induced radioactivity in a spallation neutron field of a mercury target for GeV-proton bombardment  

International Nuclear Information System (INIS)

An integral experiment on radioactivity induced in spallation neutron fields was carried out under the ASTE (AGS-Spallation Target Experiment) collaboration using AGS (Alternative Gradient Synchrotron) at BNL (Brookhaven National Laboratory). The spallation neutrons were produced by bombarding a mercury target with protons of 1.6, 12 and 24 GeV. The number of protons was 3 - 4 x 1013 for each irradiation. The irradiated materials were titanium, nickel, cobalt, yttrium, and bismuth, and placed on the cylindrical surface of the mercury target at the distance of 15 - 16 cm from the beam-incident-surface of the target. Disintegration rates of induced radioactivities were measured at several cooling-time ranging from hours to months. The principal nuclides contributing to the radioactivity were pointed out for each material. The experimental results for bismuth were compared with the calculations with DCAHIN-SP code. (author)

2001-03-01

135

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

136

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)

2008-10-19

137

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

Science.gov (United States)

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 sp(3) 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 sp(2) 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. PMID:20720292

Porrati, F; Sachser, R; Strauss, M; Andrusenko, I; Gorelik, T; Kolb, U; Bayarjargal, L; Winkler, B; Huth, M

2010-09-17

138

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

Science.gov (United States)

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.

Baddeley, L. J.; Yeoman, T. K.; Wright, D. M.; Davies, J. A.; Trattner, K. J.; Roeder, J. L.

2002-09-01

139

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

140

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)

1987-01-01

 
 
 
 
141

Analysis of Correlation Between Urinal Excretion Ratio of Radioactive Iodine and Daily Urinal Excretion Volume  

International Nuclear Information System (INIS)

Internal exposure to radionuclide results from depositing of radioactive substance within human body and is called intra-body exposure as well. Radioactive substance may find its way into human body via nose, mouth or skin and internal exposure to radionuclide is rarely ascribable to radioactive substance deposited through skin. Radioactive substances deposited in human tissues or organs do not stay there for good. Instead, they are transferred to other tissues, organs or excreted by sweat, excrements, urine and breath. However, natural excretion has its limits in terms of safeguarding human body actively against radioactive exposure. When radionuclide is deposited in human organs or tissues, diuretic or evacuant is used to induce excrements or urine to increase removal and discharging of radionuclide artificially, thereby reducing internal exposure. Therefore, we have attempted to propose an optimum approach to removing and excreting radioactive iodine by analyzing the correlation among the radioactive iodine intake ratio, daily urinal excretion ratio and volume

2006-11-02

142

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)

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)

Gensdarmes, F

2000-07-01

143

Measurement of Natural and Artificial Radioactivity in Soil at Some Selected Thanas around the TRIGA Mark-II Research Reactor at AERE, Savar, Dhaka  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The activity concentration of natural and fallout radionuclides in the soil at some selected Thanas around the TRIGA Mark-II Research Reactor at Atomic Energy Research Establishment (AERE), Savar, Dhaka were measured by using a high purity germanium detector (HPGe). The study revealed that only natural radionuclides were present in the samples and no trace of any artificial radionuclide was found. The average activity concentration of 238U, 232Th ...

2011-01-01

144

Artificial neural network for Cu quantitative determination in soil using a portable Laser Induced Breakdown Spectroscopy system  

International Nuclear Information System (INIS)

Laser Induced Breakdown Spectroscopy (LIBS) is an advanced analytical technique for elemental determination based on direct measurement of optical emission of excited species on a laser induced plasma. In the realm of elemental analysis, LIBS has great potential to accomplish direct analysis independently of physical sample state (solid, liquid or gas). Presently, LIBS has been easily employed for qualitative analysis, nevertheless, in order to perform quantitative analysis, some effort is still required since calibration represents a difficult issue. Artificial neural network (ANN) is a machine learning paradigm inspired on biological nervous systems. Recently, ANNs have been used in many applications and its classification and prediction capabilities are especially useful for spectral analysis. In this paper an ANN was used as calibration strategy for LIBS, aiming Cu determination in soil samples. Spectra of 59 samples from a heterogenic set of reference soil samples and their respective Cu concentration were used for calibration and validation. Simple linear regression (SLR) and wrapper approach were the two strategies employed to select a set of wavelengths for ANN learning. Cross validation was applied, following ANN training, for verification of prediction accuracy. The ANN showed good efficiency for Cu predictions although the features of portable instrumentation employed. The proposed method presented a limit of detection (LOD) of 2.3 mg dm-3 of Cu and a mean squared error (MSE) of 0.5 for the predictions

2008-10-01

145

Radioactivity. Fundamentals, measurement, applications. 4. rev. and enl. ed.; Radioaktivitaet. Grundlagen - Messungen - Anwendungen  

Energy Technology Data Exchange (ETDEWEB)

The following topics are dealt with: Properties of the atomic nucleus, radioactive nucleus transmutations, natural and artificial nuclides, production of radioactive nuclides, radioactive radiation sources, interaction and measurement of ionizing radiation, applications of radioactive nuclides, radiation protection. (HSI)

Stolz, W. [Technische Univ. Bergakademie Freiberg (Germany). Inst. fuer Angewandte Physik

2003-02-01

146

Isospin dependence of nucleon emission and radial flow in heavy-ion collisions induced by high energy radioactive beams  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Using an isospin- and momentum-dependent transport model we study the emission of free nucleons and the nuclear radial flow in central heavy-ion collisions induced by high energy radioactive beams. The midrapidity neutron/proton ratio and its transverse momentum dependence are found very sensitive to the high density behavior of nuclear symmetry energy. The nuclear radial flow, however, depends only weakly on the symmetry energy.

Li, Bao-an; Yong, Gao-chan; Zuo, Wei

2004-01-01

147

A new possible biological interface model useful to narrate the artificial negative events by the radioactive contaminations and heavy-metals pollution of the soil and the atmosphere in different areas of Europe  

International Nuclear Information System (INIS)

A lot of environmental negative effects are associated to the pollution and radioactive contaminations of the soil and the atmosphere. Actually the C.I.S.A.M. (Interforces Centre for Studies and Military Applications) receives increasing commitments to control and to knowledge about the risks of the population and soldiers employed as stabilization or keeping peace force in large areas of different territories of Europe and other sites of the Planet. The aim of this work is focused to compare the contents of radionuclides on specific natural interfaces in different areas as residual radioactive contamination in addition to the other possible heavy-metals pollution. We used barks, lichens and symbiontic microalgae as interfaces with the atmospheric events of the Chernobyl, Balkan, and the Italian areas. The qualitative analysis of these biological matters showed the constant presence of Radiocesium, along with other radionuclides, of which we report the concentrations. Even if these observations are not completely new, nevertheless we can suppose that this approach could be a new possible interface model useful to narrate the sequence of the the artificial negative events due to the human activities and contemporarely an indirect valuation of different risks pointed to the protection of the exposed population

2002-10-08

148

Very low levels of artificial radioactivity in the environment in 2009; Des niveaux de radioactivite artificielle qui restent tres faibles dans l'environnement en 2009 (IRSN)  

Energy Technology Data Exchange (ETDEWEB)

The 2009 edition of the annual state of the environment in France concerning radioactivity shows very low levels of radioactivity that are consistent with previous measurements. The radiological survey of 3 particular areas (Val de Loire, south-west of France and Rhone valley) has been made through several measurement campaigns that have involved for each area the recovery of between 100 to 200 samples in the different segments of the environment. This radiological state will be a standard for the area concerned. The 2009 edition reports also the radiological surveys of 3 ancient industrial sites: detection of Thorium 232 on the site of the Orflam-Plast company at Pargny-sur-Saulx (Marne department), detection of Carbon 14 around the ancient laboratory of the Isotopchim company near Forcalquier (Alpes de Haute Provence department) and radium contamination on the ancient site of the Satchi company at Charvet (Seine Saint-Denis department). (A.C.)

Anon.

2011-01-15

149

Assessment of Artificially Induced Pressure Sores Using a Modified Fractal Analysis  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this study, a guinea pig model has been developed for generation and monitoring of pressure sores. A system with pressure sensors and a suitable feedback was used for inducing pressure sores. High-frequency ultrasound images were taken from the wound site after tissue was released from the applied pressure for a 21 days period. Fractal properties of the selected windows were calculated, which leads to proposing a Modified Fractal Signature (MFS). The MFS proved to be an efficient me...

Moghimi, S.; Miran Baygi, M. H.; Torkaman, G.; Mahlooji Far, A.

2009-01-01

150

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

2005-07-25

151

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

152

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)

2012-01-01

153

Isolation and characterization of BoHV-1 from seropositive cows after inducing artificial stress in West Bengal, India.  

Science.gov (United States)

Infectious Bovine Rhinotracheitis (BoHV-1) is the most important emerging disease of cattle in India. With an aim to reactivate BoHV-1 from latently infected sero-positive cattle for molecular characteristics of the isolates prevalent in tropical and sub-tropical countries like India and further epidemiological investigations on IBR infections this study had been conducted. Artificial stress with dexamethasone at the dose rate of 0.1 mg kg(-1) body weight for 5 consecutive days was induced in BoHV-1 sero-positive cows. Then isolation from nasal swabs was attempted in Madin Darby Bovine Kidney (MDBK) cell line to find out the prevalent strain in India. The virus was isolated from all the three cows. All the three isolates were typed as BoHV-1.2 (Strain India 4, India 5 and India 6). The reactivation obtained in this study with dexamethasone suggests the usefulness of BoHV-1 cow latency model for epidemiological investigations on BoHV-1 infections in tropical and sub-tropical countries like India, Pakistan etc. PMID:24505999

Saha, Tapabrata; Guha, Chanchal; Chakraborty, Dhruba; Pal, Biplab; Biswas, Ujjwal; Chatterjee, Amaresh; Koenig, Patricia; Beer, Martin

2013-08-01

154

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

Directory of Open Access Journals (Sweden)

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

L. J. Baddeley

155

Radioactive ion beams produced by neutron-induced fission at ISOLDE  

International Nuclear Information System (INIS)

The production rates of neutron-rich fission products for the next-generation radioactive beam facility EURISOL [EU-RTD Project EURISOL (HPRI-CT-1999-50001)] 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 [E. Kugler, Hyperfine Interact. 129 (2000) 23], 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 and tantalum converters, are presented. To gain further knowledge for the design of a dedicated target as required by the TARGISOL project [EU-RTD Project TARGISOL (HPRI-CT-2001-50033)], the results are compared to simulations, using the MARS [N.V. Mokhov, S.I. Striganov, A. Van Ginneken, S.G. Mashnik, A.J. Sierk, J. Ranft, MARS code developments, in: 4th Workshop on Simulating Accelerator Radiation Environments, SARE-4, Knoxville, USA, 14-15.9.1998, FERMILAB-PUB-98-379, nucl-th/9812038; N.V. Mokhov, The Mars Code System User's Guide, Fermilab-FN-628, 1995; N.V. Mokhov, MARS Code Developments, Benchmarking and Applications, Fermilab-Conf-00-066, 2000; O.E. Krivosheev, N.V. Mokhov, A New MARS and its Applications, Fermilab-Conf-98/43, 1998] code interfaced with MCNP [J.S. Hendrics, MCNP4C LANL Memo X-5; JSH-2000-3; J.F. Briemesteir (Ed.), MCNP - A General Montecarlo N-Particle Transport Code, Version 4C, LA-13709-M] libraries, of the neutron flux from the converters interacting with the actinide targets

2003-05-01

156

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

1948-05-24

157

Assessment of Artificially Induced Pressure Sores Using a Modified Fractal Analysis  

Directory of Open Access Journals (Sweden)

Full Text Available In this study, a guinea pig model has been developed for generation and monitoring of pressure sores. A system with pressure sensors and a suitable feedback was used for inducing pressure sores. High-frequency ultrasound images were taken from the wound site after tissue was released from the applied pressure for a 21 days period. Fractal properties of the selected windows were calculated, which leads to proposing a Modified Fractal Signature (MFS. The MFS proved to be an efficient measure for assessing the pressure sores. Exploiting the proposed idea, the progression of necrotic tissue could be studied. It is shown that this measure is also capable of evaluating the healing process of pressure sores.

S. Moghimi

2009-01-01

158

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

Directory of Open Access Journals (Sweden)

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.

R. Napoli

1998-06-01

159

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

Science.gov (United States)

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

Trojak-Goluch, Anna; Skomra, Urszula

2013-12-01

160

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)

2012-10-01

 
 
 
 
161

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

Energy Technology Data Exchange (ETDEWEB)

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.

Brai, Maria; Gennaro, Gaetano [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze Ed.18, 90128 Palermo (Italy); Schillaci, Tiziano, E-mail: tschillaci@unipa.i [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze Ed.18, 90128 Palermo (Italy); Tranchina, Luigi [Dipartimento di Fisica e Tecnologie Relative, Universita di Palermo, Viale delle Scienze Ed.18, 90128 Palermo (Italy)

2009-10-15

162

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

Science.gov (United States)

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.

Trojak-Goluch, Anna; Skomra, Urszula

2013-01-01

163

Indução à ovulação pelo uso de LHRH análogo e fertilização artificial em rã-touro (Rana catesbeiana) / Spawning inducing by analog LHRH and artificial fertilization of bullfrog (Rana catesbeiana)  

Scientific Electronic Library Online (English)

Full Text Available SciELO Brazil | Language: Portuguese Abstract in portuguese Este trabalho teve por objetivo aperfeiçoar a técnica de reprodução induzida existente para rã-touro, com o intuito de aumentar a taxa de fecundidade e viabilizar seu uso pelo produtor. As doses hormonais para a indução da ovulação e espermiação seguiram as propostas de FALCON e CULLEY (1995) e ALON [...] SO (1997); entretanto, a técnica de fertilização artificial foi adaptada da metodologia para reprodução artificial de peixes com ovos não-aderentes (WOYNAROVICH e HORVÁTH, 1983). A técnica proposta apresenta as seguintes etapas: I) sincronização da ovulação e da espermiação, por meio de hormônio liberador de gonadotropina ((Des-Gli10, D-His(Bzl)6, Pro-NHEt9)-LHRH)); II) extração dos óvulos de cada fêmea (1 a 2 minutos); III) fertilização dos óvulos (2 minutos) com líquido espermático diluído em 100 mL de água; IV) hidratação dos ovos em 10 a 20 litros de água; e V) incubação dos ovos em quadros de tela de 1x 0,70 m, com malha de 1 mm. As taxas de fertilização obtidas com as modificações propostas foram superiores a 60%. Ressalta-se ainda que a técnica propiciou a obtenção, a partir de um mesmo animal, de várias desovas, sendo que cada fêmea pode ovular em intervalos de, aproximadamente, 45 dias. Abstract in english The objective of this study was to improve the artificial fertilization techniques for bullfrog, to increase the fertilization rate and become their use accessible for frog producers. Hormone dosages for inducing ovulation and spermiation followed those proposed by FALCON and CULLEY (1995) and ALONS [...] O (1997); however, the artificial fertilization technique was adapted from the available methodology for artificial reproduction of fish with non-adhering eggs (WOYNAROVICH e HORVÁTH, 1983). The proposed technique consists of the following steps: I) synchronization of ovulation and spermiation through gonadotropin releasing hormone ((Des-Gli10, D-His(Bzl)6, Pro-NHEt9)-LHRH)); II) complete ovule extrusion in every female (1 to 2 minutes); III) ovule fertilization (2 minutes) with sperm diluted in 100 mL water; IV) ova hydration in 10 - 20 L water; V) ova incubation in screen frames, measuring 1,0 x 0,7 m, with 1 mm screen size. Fertilization rate obtained with the proposed modifications stayed above 60 %. It should also be emphasized that the proposed techniques allowed to obtain several spawns from the same frog, and each female was able to ovulate, approximately, every 45 days.

Claudio Angelo, Agostinho; Francisco Stefano, Wechsler; Paulo Eduardo de Oliveira, Nictheroy; Daniela Felipe, Pinheiro.

164

Artificial blood  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Sarkar Suman

2008-01-01

165

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

Science.gov (United States)

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.

Lokier, Stephen; Krieg Dosier, Ginger

2013-04-01

166

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Fujiwara, Keiko; Kinashi, Yuko; Takahashi, Tomoyuki; Yashima, Hiroshi; Kurihara, Kouta; Sakurai, Yoshinori; Tanaka, Hiroki; Ono, Koji; Takahashi, Sentaro

2013-01-01

167

Artificial Intelligence.  

Science.gov (United States)

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…

Thornburg, David D.

1986-01-01

168

Comparison of thermally induced and naturally occurring water-borne leakages from hard rock depositories for radioactive waste  

International Nuclear Information System (INIS)

The relative importance of thermally induced and naturally occurring flows of water as causes of leakage from hard rock depositories for radioactive wastes is assessed. Separate analyses are presented for involatile, high level waste from reprocessing of fuel and for plutonium contaminated waste from fabrication of fuel. The effects of varying the quantities of wastes, pre-burial storage and the shapes and depths of depositories are considered. It is concluded that for representative values of these variables, thermal flow will remain the major cause of leakage for long times after the burial of both types of waste. (Auth.)

1981-01-01

169

Artificial blood  

Directory of Open Access Journals (Sweden)

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.

Sarkar Suman

2008-01-01

170

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

Energy Technology Data Exchange (ETDEWEB)

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{plus minus}2.13 Bq/mgCo and the Eu-152 activity was 75.9{plus minus}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).

Okumura, Yutaka; Shimasaki, Tatsuya; Yoshida, Masahiro (Nagasaki Univ. (Japan). School of Medicine); Takatsuji, Toshihiro; Takada, Jitsuya

1989-01-01

171

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)

2013-07-01

172

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)

1950-01-00

173

Characterization and comparison of seismic signals emitted during field scale sheer box experiments and artificially induced landslides  

Science.gov (United States)

The identification and detection of landslide induced seismic signals, recorded by deployed seismometers on active landslides has been the subject of many studies. The most commonly faced problem is the uncertainty in identifying which of the recorded signals are representing a movement or a failure in the landslide's body. In this paper we present two novel experimental campaigns; 1) field scale laboratory experiments of a 65cm diameter sheer box, 2) artificially induced failure of two, two-meter high vertical soil slopes. Using a field scale sheer box we recorded seismic signals emitted during soil slippage events, a phenomenon observed at a landslide's failure plain. This was implemented by displacing, a few centimeters at a time (1-10cm), a concrete cylinder filled with soil along a corridor free from vegetation. The field scale sheer box methodology allows control over a large number of parameters that affect a landslide. For example, it is possible to control soil saturation thus simulating different rain events or control the stress field on the soil's slippage surface simulating displacement events at different depths. More than 40 displacement events were induced under four different loading conditions between 472kg to 829kg. All soil slippage events were recorded above the levels of background seismic noise. Repetition of the methodology under the same experimental conditions resulted in similar seismic signals allowing us to define a 'characteristic seismic response' for soils. In the second experimental campaign, two controlled landslides were experimentally induced by increasing the vertical load on top of a 2m soil scarp. We were able to detect from 1 to 10 centimeter wide crack propagations and displacements, and approximately 20x20x10cm to 100x50x20cm block failure events based on microseismic recordings, field notes, video recordings and displacement measurements of the landslide's crown that failed during the experiments. Direct correlation between these visual recordings with seismic signals produced unique frequency patterns. Scanning all seismic data searching for these patterns allowed for detection of displacement events within the recordings that were not observed visually and were likely located within the landslide's mass. Both experimental campaigns were recorded by short period 3D seismic sensors. In order to validate the signals emitted using the sheer box methodology we compared them to the small displacement events recorded in the landslide experiments in the frequency domain by calculating their power spectral densities. Our results show close similarity between the two, validating the field scale lab experiment as a tool for preliminary understanding of the expected seismicity of an active landslide. Our study demonstrates the potential of microseismic motoring for detecting small soil displacements and soil block failures above ambient noise levels, as part of an active landslide monitoring campaign. Future research will use these results to design a monitoring network based on the threshold for event detection, which is a function of the displacement rate and the source-to-receiver distance. To our knowledge these are the first controlled field experiments that can allow validation and calibration of seismic monitoring for landslide detection.

Yfantis, Georgios; Martinez Carvajal, Hernan Eduardo; Pytharouli, Stella; Lunn, Rebecca

2014-05-01

174

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)

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)

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

1969-07-01

175

The artificial surface-induced whole blood inflammatory reaction revealed by increases in a series of chemokines and growth factors is largely complement dependent.  

Science.gov (United States)

Exposing blood to an artificial surface results in a systemic inflammatory response, including cytokine release and complement activation. We studied the artificial surface-induced inflammation in human whole blood using an extensive panel of inflammatory mediators including proinflammatory cytokines, chemokines and growth-factors and investigated the role of the complement system in the induction of this response. Using multiplex technology, 27 different inflammatory mediators were measured after circulating blood for 4 hours in polyvinyl chloride tubing. The C3 inhibitor compstatin was used to block complement activation. A significant (p < 0.05) increase in 14 of the 27 mediators was induced by the surface, of which 7 were chemokines (IL-8, MCP-1, MIP-1alpha, MIP-1beta, RANTES, eotaxin and IP-10) and 5 were growth-factors (G-CSF, GM-CSF, VEGF, PDGF and FGF). The traditional proinflammatory cytokines like IL-1beta, TNFalpha and IL-6 were not induced, although IL-6, as well as IL-15 and IL-17 increased if the surface was coated with highly bioincompatible laminaran. Inhibition of complement activation with compstatin significantly (p < 0.05) reduced the formation of 12 of the 14 mediators. For 10 of the 12 mediators, the inhibition was by 2/3 or more, for the remaining two the inhibition was more moderate. A highly biocompatible heparin-coated PVC surface was used as negative control and completely abolished the whole inflammatory response. The artificial surface PVC markedly induced a broad spectrum of chemokines and growth-factors, which was largely dependent on activation of complement. PMID:18085644

Lappegård, K T; Bergseth, G; Riesenfeld, J; Pharo, A; Magotti, P; Lambris, J D; Mollnes, T E

2008-10-01

176

The development of ferritic steels for fast induced-radioactivity decay for fusion reactor applications  

International Nuclear Information System (INIS)

The Cr-Mo ferritic (martensitic) steels are leading candidates for the structural components for future fusion reactors. However, irradiation of such steels in a fusion environment produces long-lived radioactive isotopes that lead to difficult waste disposal problems once the structure is removed from service. One method proposed to alleviate such problems is the development of 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). For such solution for the Cr-Mo steels, molybdenum must be eliminated. In addition, niobium must be maintained at extremely low levels. Tungsten is proposed as an appropriate substitution for molybdenum, and the procedures for developing Cr-W steels analogous to the Cr-Mo steels are discussed. (orig.)

1985-07-01

177

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)

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.

Shevchenko ?. A.

2014-03-01

178

Artificial Blood  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 ...

Umit Yasar; Pinar Yilgor Huri; Nurten Dikmen

2012-01-01

179

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

International Nuclear Information System (INIS)

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

2007-09-01

180

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

Energy Technology Data Exchange (ETDEWEB)

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

Huang Yaoxiong; Li Qinhua [Institute of Biomedical Engineering, Ji Nan University, Guang Zhou (China)

2007-09-15

 
 
 
 
181

31P NMR characterization of terminal phosphates induced on DNA by the artificial nuclease 'Mn-TMPyP/KHSO5' in comparison with DNases I and II.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Phosphorus-31 NMR has been applied to the characterization of terminal phosphates on fragments of calf thymus DNA induced by three different nuclease systems: DNase I, DNase II and the artificial nuclease 'Mn-TMPyP/KHSO5'. In this last case, the oxidative damage to deoxyribose leads to two monophosphates esters (at the 3' and 5' ends) on both sides of the cleavage site. This method constitutes a promising approach to visualise the phosphate termini generated in DNA or RNA cleavage by cytotoxi...

Gasmi, G.; Pasdeloup, M.; Pratviel, G.; Pitie?, M.; Bernadou, J.; Meunier, B.

1991-01-01

182

Response of native flora to inducible genotoxic damage from increased radioactivity around NPP Jaslovske Bohunice, Slovakia  

International Nuclear Information System (INIS)

It is not generally known that the first serious failure of nuclear power plant (NPP) technology with loss of human lives occurred in NPP Jaslovske Bohunice (Czechoslovakia) in January 1976. A year later the second accident finally broken reactor A1 with large radioactive contamination. This material was later (in 1980) washed into the nearby drainage by the heavy rain. In cleaning procedure, the contaminated soil particles contaminated the slopes of the drainage. These spots have the shape of 'blurs' about 15 cm wide with a scale of contamination from 0,067; 0,15; 2,38; 9,5; 45.5 up to 322 kBq/kg 137Cs. The research was done in cooperation with the Institute of Tumorbiology, University of Vienna, within the grant Action Austria - Slovak Republic. Details of radioactivity at the area were obtained thanks to the Research Institute of the Nuclear Energy in Trnava, Slovakia. In our ten years long-term study of contaminated soil around nuclear power plant (NPP) Jaslovske Bohunice 24 species of local flora were used to show impact of these accidents. The 19 km long banks of the Jaslovske Bohunice NPP waste water recipient has been identified as contaminated by 137Cs. In total, more than 67,000 m2 of river banks have been found as being contaminated at levels exceeding 1 Bq 137Cs/g of soil. Used phytotoxic and cytogenetic -in situ' tests were extended by analyses of pollen grains. Although the dose of some samples of radioactive soil was relatively high (322 kBq kg-1) no any significant impact on the biological level of tested wild plant species was observed. Possible explanation (such as adaptation and resistance) is discussed. (author)

2008-08-12

183

Implantation of artificial whiskers on the ears of newborn mice induces visual re-mapping in the superior colliculus.  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In newborn mice, we modified the body scheme by implanting artificial whiskers (pig hair) on the ears, which are located in the superior and temporal portions of the visual field. In normal mice, multisensory neurons in the deep layers of the superior colliculus receiving somatosensory input from the ears showed visual receptive fields in the superior and temporal portions of visual space. By contrast, in the implanted mice, there was a modification of the visual receptive fields strictly rel...

Benedetti, Fabrizio

1994-01-01

184

Correlation between radioactivity induced inside the treatment room and the undesirable thermal/resonance neutron radiation produced by linac.  

Science.gov (United States)

High-energy therapeutic beams used in the radiotherapy induce photonuclear and electronuclear reactions which are accompanied by generation of undesirable radioisotopes and neutrons inside the treatment room. These neutrons at thermal and resonance energies induce nuclear reactions through the whole accelerator bunker. In consequence various radioisotopes emitting high-energy photons appear. In this paper the correlation between radioactivity induced inside the treatment room and the undesirable thermal and resonance neutron radiation generated by the therapeutic accelerator X-rays was studied. The thermal and resonance neutron fluence determined in chosen places inside the bunkers was 1.0x10(5)-3.4x10(5)cm(-2)Gy(-1) and 1.0x10(5)-1.6x10(6)cm(-2)Gy(-1) at thermal energies (epithermal energies (0.1eV-10keV), for the 15MV and 20MV beams, respectively. The gamma energy spectra measured inside the accelerator bunker depended on the neutron radiation level. The net count rates of the gamma peaks from the decays of the excited state (56)Fe* and (28)Si*, the result of the simple capture of the neutron, for the 20MV beam were almost one order of magnitude greater than those for the 15MV beam. Moreover, it turned out that the activation of the wedge - the main accelerator accessory was caused by neutrons. PMID:18339569

Konefa?, Adam; Orlef, Andrzej; Dybek, Marcin; Maniakowski, Zbigniew; Polaczek-Grelik, Kinga; Zipper, Wiktor

2008-12-01

185

Man and radioactivity; L'Homme et la radioactivite  

Energy Technology Data Exchange (ETDEWEB)

This brochure resumes the general subjects connected to the radioactivity: what matter is; atoms and molecules; the different types of disintegration; gamma emission; isotopes; halftime; radioactivity and units; exposure to radioactivity; natural and artificial radioactivity; nuclear energy; radioactive wastes; regulations on radioactive waste; nuclear reactors in France; principles of reactors functioning; safety of nuclear reactors; nuclear reactors types; irradiation; contamination; biological radiation effects. (N.C.)

Foos, J

2006-07-01

186

Artificial sunlight and ultraviolet light induced photo-epoxidation of propylene over V-Ti/MCM-41 photocatalyst  

Science.gov (United States)

Summary The light irradiation parameters, including the wavelength spectrum and intensity of light source, can significantly influence a photocatalytic reaction. This study examines the propylene photo-epoxidation over V-Ti/MCM-41 photocatalyst by using artificial sunlight (Xe lamp with/without an Air Mass 1.5 Global Filter at 1.6/18.5 mW·cm?2) and ultraviolet light (Mercury Arc lamp with different filters in the range of 0.1–0.8 mW·cm?2). This is the first report of using artificial sunlight to drive the photo-epoxidation of propylene. Over V-Ti/MCM-41 photocatalyst, the propylene oxide (PO) formation rate is 193.0 and 112.1 µmol·gcat ?1·h?1 with a PO selectivity of 35.0 and 53.7% under UV light and artificial sunlight, respectively. A normalized light utilization (NLU) index is defined and found to correlate well with the rate of both PO formation and C3H6 consumption in log–log scale. The light utilization with a mercury arc lamp is better than with a xenon lamp. The selectivity to PO remains practically unchanged with respect to NLU, suggesting that the photo-epoxidation occurs through the same mechanism under the conditions tested in this study.

Nguyen, Van-Huy; Bai, Hsunling

2014-01-01

187

Artificial sunlight and ultraviolet light induced photo-epoxidation of propylene over V-Ti/MCM-41 photocatalyst.  

Science.gov (United States)

The light irradiation parameters, including the wavelength spectrum and intensity of light source, can significantly influence a photocatalytic reaction. This study examines the propylene photo-epoxidation over V-Ti/MCM-41 photocatalyst by using artificial sunlight (Xe lamp with/without an Air Mass 1.5 Global Filter at 1.6/18.5 mW·cm(-2)) and ultraviolet light (Mercury Arc lamp with different filters in the range of 0.1-0.8 mW·cm(-2)). This is the first report of using artificial sunlight to drive the photo-epoxidation of propylene. Over V-Ti/MCM-41 photocatalyst, the propylene oxide (PO) formation rate is 193.0 and 112.1 µmol·gcat (-1)·h(-1) with a PO selectivity of 35.0 and 53.7% under UV light and artificial sunlight, respectively. A normalized light utilization (NLU) index is defined and found to correlate well with the rate of both PO formation and C3H6 consumption in log-log scale. The light utilization with a mercury arc lamp is better than with a xenon lamp. The selectivity to PO remains practically unchanged with respect to NLU, suggesting that the photo-epoxidation occurs through the same mechanism under the conditions tested in this study. PMID:24991493

Nguyen, Van-Huy; Lin, Shawn D; Wu, Jeffrey Chi-Sheng; Bai, Hsunling

2014-01-01

188

Induced structural radioactivity inventory analysis of the base case aqueous ATW reactor concept  

Energy Technology Data Exchange (ETDEWEB)

The purpose of the Los Alamos National Laboratory Accelerator Transmutation of Nuclear Waste (ATW) project is the substantial reduction in volume of this country`s long-lived high-level radioactive waste in a safe and energy efficient manner. An evaluation of the Accelerator Transmutation of Nuclear Waste 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. An activation analysis has been performed on four structure regions of the reaction vessel: the tungsten target; the lead target and annulus; the Zircalloy and aluminum tubing carrying the actinide slurry and; the stainless steel tank.

Bezdecny, J.A.; Henderson, D.L. [Wisconsin Univ., Madison, WI (United States); Sailor, W.C. [Los Alamos National Lab., NM (United States)

1993-12-31

189

Tide induced mathematical model for coastal radioactive discharges and its application  

International Nuclear Information System (INIS)

A mathematical model has been developed to evaluate spatial and temporal distribution of radionuclide concentration from a continous discharge of radioactive liquid effluents into the Tarapur coastal waters, taking into consideration tidal effects and seasonal variation of ocean currents. It is found that all the nuclides studied except 131I, attain steady state concentration more or less at the same time interval after continuous discharge, depending on the distance along the coast. Further, the confinement of radionuclides parallel to the coast is significant. Limiting discharge rates (LDR) for some typical radionuclides have also been computed using a radiological model. The calculations show the the LDR values vary from 7 to 50,000 Ci.d-1, the lowest and highest being for 239Pu and 134Cs respectively. (author)

1985-03-01

190

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)

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.

KunjumonIVadakkan

2011-07-01

191

Induced Radioactivity Measured in a Germanium Detector After a Long Duration Balloon Flight  

Science.gov (United States)

A 13-day long duration balloon flight carrying a germanium detector was flown from Williams Field, Antartica in December 1992. After recovery of the payload the activity induced in the detector was measured.

Starr, R.; Evans, L. G.; Floyed, S. R.; Drake, D. M.; Feldman, W. C.; Squyres, S. W.; Rester, A. C.

1997-01-01

192

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.

2010-11-30

193

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

194

Simulation of induced radioactivity in collimating materials under cosmic proton irradiation  

International Nuclear Information System (INIS)

?-ray spectra from lead and tungsten targets irradiated by cosmic protons, corresponding to near-Earth orbits, are calculated using a Monte Carlo method. The influence of the South-Atlantic anomaly is taken into account. Prompt radiation (in the interval of 10-6 to 10-15 s) and ?-radiation from induced activity have been studied depending on exposure time (in the interval from several days up to a year). The induced ?-activity is found to be of similar magnitude as the background radiation, however, in some cases it can even be somewhat higher than the background. (orig.)

1989-12-01

195

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

Energy Technology Data Exchange (ETDEWEB)

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

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

2006-04-12

196

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

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

1983-01-01

197

Validation of induced radioactivity calculations for candidate fusion materials through measurements in a graphite-centered assembly  

International Nuclear Information System (INIS)

Induced radioactivity measurements were carried out jointly by the USA and Japan in a graphite-centered assembly, in the framework of ITER Task T-218 entitled 'Shielding Blanket Neutronics Experiments'. An intense, accelerator-based D-T rotating target neutron source JAERI, with a nominal intensity of 5 x 1012 s-1, was used. Two locations, providing different neutron energy spectra, were chosen for irradiating samples of a range of materials of interest to ITER. Three independent experimental campaigns were conducted so as to accommodate a large number of samples, on one hand, and as many short and long half-life products as possible, on the other. The total neutron fluence ranged from 4.7 x 1011 to 1.5 x 1014 n cm-2. Altogether, samples of Mg, Al, SiO2, Ti, V, Cr, Mn, Fe, Co, Ni, FH82 steel, SS316LN steel (ITER grade), Cu, Zn, KCl, Zr, Nb, Mo, Ag, ln, Sn, Dy, Ta, Hf, Re, Au, Ir, and Pb were irradiated. The irradiated samples were cooled for variable periods ranging from 30 s to 250 days before their decay gamma-ray spectra were counted on high purity intrinsic germanium detectors. The half lives of the observed radioisotopes have ranged from 18.7 s (46mSc from Ti) to 5.3 years (60Co from Ni). The neutron energy spectra for the two locations were calculated using Monte Carlo code MCNP with FENDL-1 and ENDF/B-VI data libraries. The analysis of isotopic activities, expressed in Bq cc-1, of the irradiated materials has been carried out using REAC-3 radioactivity code, with FENDL-2A and FENDL-1A activation cross-section and decay data libraries. Typically, C/E lies in a band of 0.5-1.5 for the results being reported. (orig.)

1998-09-01

198

Environmental radioactivity annual report 1987  

International Nuclear Information System (INIS)

Artificial radioactivity in the environment in New Zealand and at Rarotonga during 1987 continued to be at the very low level typical of recent years. Average levels were: total beta activity in air, 0.07 mBq m-3; strontium-90 deposition, 0.4 ± 0.3 MBq km-2; caesium-137 in milk, 0.19 Bq gK-1; strontium-90 in milk, 0.045 Bq gCa-1. No artificial radionuclides were detected on high-volume air filters. It is concluded that there was no influx of fresh radioactive emissions into the region during 1987. (author). 5 refs., 3 tabs

1988-01-01

199

Radioactive decay  

International Nuclear Information System (INIS)

The decay of isolated radionuclides is studied. It includes, a table of selected half lives, selected values and corresponding uncertainties and also universal decay tables. The second part deals with the growth of radioactive products. The general relations for two, three and n bodies are given. As an illustration of these relations, some significant cases are thoroughly examined. The third part deals with activation problems, as well of first order as of the second and in the cases where the primary radionuclide can or not be activated. Some relations give induced activity in several different situations. The case of periodic activation is also dealt with

1980-01-01

200

gamma radiation -induced preparation of some resins for the separation of radioactive isotopes  

International Nuclear Information System (INIS)

organic resins have many applications not only in the industrial and environmental fields but also in the nuclear field, this may be returned to its high measured capacity, high selectivity, low solubility and high chemical radiation stability. in this work, gamma radiation was used in the preparation of p(AM-AA-DMAEM) and p(AM-AA)-EDTANa2 using template polymerization technique in the presence of N,N'-methylene-diacrylamide (DAM) as a crosslinked. characterization of the prepared polymeric resins was studied by using infrared spectra to determine all function groups in the obtained polymeric materials . p(AM-AA-DMAEM)and p(AM-AA)-EDTANa2, were used for the sorption of Ga(lll), Cu(ll),Ni(ll) and Zn(ll) in aqueous solution as single component system. the effect pf ph, weight of resins, metal ion concentrations and contact time on the sorption of these metal ions were studied. also, p(AM-AA-DMAEM)and p(AM-AA)-EDTANa2 were used for the separation of these metal ions were studied. also,p( AM-AA-DMAEM)and p(AM-AA)-EDTANa2 were used for the separation of Ga(lll), from Cu (ll), Ni (ll), and Zn(ll) in aqueous media. the effect pf ph, contact time and the weight of the resin on the separation were studied using batch technique. chromatographic separation of Ga(lll) from Cu(ll), Ni (ll), and Zn (ll) onto p(AM-AA-DMAEM)and p(AM-AA)-EDTANa2 was also studied. the effect of flow rate, breakthrough curves, stability test of resins, and cyclic properties of the resins were studied in details. batch experiments for testing the capability of polymeric resins for the sorption of radioactive isotope (72Ga) that produced from the reactor were studied

2008-01-01

 
 
 
 
201

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

1997-01-01

202

Timescale of natural annealing in radioactive minerals affects retardation of radiation-damage-induced leaching  

Energy Technology Data Exchange (ETDEWEB)

The paper concerns natural annealing and radiation-damage-induced leaching in solidified nuclear materials. Results are presented of radioisotope measurements on ancient uranium- and thorium-rich materials, which indicate that 'self-annealing' strikingly reduces the rate of dissolution. An annealing time of 15 k yr is estimated. The results also suggest a localized submicroscopic loss of order. Finally the data infers that minerals in which such annealing occurs could be suitable for nuclear waste-storage media.

Eyal, Y. (General Electric Co., Schenectady, NY (USA). Corporate Research and Development Center; Technion-Israel Inst. of Tech., Haifa. Dept. of Nuclear Engineering); Fleischer, R.L. (General Electric Co., Schenectady, NY (USA). Corporate Research and Development Center)

1985-04-11

203

Artificial Wetlands  

Science.gov (United States)

Golf courses are known as places of recreation. But some of them could someday double as water treatment facilities. Water hazards on golf courses can be used to control environmental hazards. That's according to Purdue University soil microbiologist Ron Turco. He says the artificial wetlands can also control flooding in surrounding communities, by collecting excess water. This Science Update looks at the research, which leads to these findings and offers links to other resources for further inquiry.

American Association for the Advancement of Science (;)

2005-04-11

204

Artificial heart  

Energy Technology Data Exchange (ETDEWEB)

Super-pure plutonium-238 could use heat produced during fission to power an implanted artificial heart. Three model hearts have worked for some time. Concern that excess heat would make the procedure unsafe for humans has broadened the search for another energy source, such as electrohydraulic drive or an external power battery. A back pack approach may provide an interim solution until materials are developed which can withstand heart activity and be small enough for implantation.

1984-10-18

205

Immunostimulatory response induced by supplementation of Ficus benghalensis root powder, in the artificial feed the Indian freshwater murrel, Channa punctatus.  

Science.gov (United States)

Methanol extract from the dried aerial root of Ficus benghalensis, was used to evaluate antibacterial activity on the bacterial strains of Aeromonas hydrophila and Escherichia coli, by disc diffusion method. In order to study, if there is any immunostimulatory response of F. benghalensis, immunized fish were fed with supplementary artificial feed containing 5% F. benghalensis dried root powder. There was no marked difference in the levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in control and treated fish, suggesting that the supplementary feed had no adverse effect on liver or kidney. Serum lysozyme, tissue super oxide dismutase (SOD), percentage phagocytosis, phagocytotic index, nitric oxide (NO), total serum protein and immunoglobulin increased significantly in the treated fish compared to control fish. Serum immunoglobulin levels were estimated by development of a sandwich ELISA, and levels were found to increase with successive immunizations of BSA. PMID:22789713

Verma, Vipin Kumar; Rani, Kumari Vandana; Sehgal, Neeta; Prakash, Om

2012-09-01

206

Geochemical ways of artificial radionuclide migration in biosphere  

International Nuclear Information System (INIS)

The collection contains abstracts of papers concerning aspects of distribution, forms and migration of artificial radionuclides in biosphere, simulation of their behaviour in separate components and systems. Methods of radioactivity monitoring in biosphere are discussed

1990-01-01

207

Validation of the FLUKA Monte Carlo code for predicting induced radioactivity at high-energy accelerators  

Energy Technology Data Exchange (ETDEWEB)

Samples of different materials, consisting of major elements with masses up to the one of copper, were exposed to the stray radiation field created by a 120 GeV hadron beam in a copper target. The induced specific activities of radionuclides, as measured with gamma spectrometry, then served as benchmark of the FLUKA Monte Carlo code. A careful analysis of the experimental data as well as of the reactions leading to the various isotopes in the simulation demonstrated that FLUKA is capable of predicting individual isotopes with an uncertainty of less than 20-30% in most cases. Due to the universal nature of the high energy interaction models the results also serve as indirect validation of FLUKA predictions for target materials, reactions and isotopes not covered by this study.

Brugger, M. [CERN, CH-1211 Geneva 23 (Switzerland); Ferrari, A. [CERN, CH-1211 Geneva 23 (Switzerland); Roesler, S. [CERN, CH-1211 Geneva 23 (Switzerland)]. E-mail: Stefan.Roesler@cern.ch; Ulrici, L. [CERN, CH-1211 Geneva 23 (Switzerland)

2006-06-23

208

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

Energy Technology Data Exchange (ETDEWEB)

This paper presents a detailed study of the {beta} decay continuum background in a spaceborn Ge spectrometer (SPI) and methods for its reduction. In the nuclear {gamma}-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 {beta}{sup -} and {beta}{sup +} 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.

Diallo, N. E-mail: nd@sousun.phys.soton.ac.uk; Jean, P.; Legrain, R.; Cordier, B.; Vedrenne, G.; Kandel, B.; Salassi-Sennou, S

2000-12-11

209

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

2000-12-11

210

Validation of the FLUKA Monte Carlo code for predicting induced radioactivity at high-energy accelerators  

International Nuclear Information System (INIS)

Samples of different materials, consisting of major elements with masses up to the one of copper, were exposed to the stray radiation field created by a 120 GeV hadron beam in a copper target. The induced specific activities of radionuclides, as measured with gamma spectrometry, then served as benchmark of the FLUKA Monte Carlo code. A careful analysis of the experimental data as well as of the reactions leading to the various isotopes in the simulation demonstrated that FLUKA is capable of predicting individual isotopes with an uncertainty of less than 20-30% in most cases. Due to the universal nature of the high energy interaction models the results also serve as indirect validation of FLUKA predictions for target materials, reactions and isotopes not covered by this study

2006-06-23

211

An experimental investigation of radioactivity induced by ions associated with the operation of pulsed power accelerators  

International Nuclear Information System (INIS)

Energetic light ion beams are being studied in Sandia National Laboratories' Particle Beam Fusion Accelerator 11 (PBFA II) for the purpose of studying the physics of applied B-diodes with the hope that these beams can be applied to inertial confinement fusion. These beams induce nuclear reactions both in the diode itself and in the materials surrounding the diode. A series of experiments was conducted wherein samples of metals typically used in the diode/gas cell region of PBFA II were exposed to ion beams at energies expected to be achieved in PBFA II. The metals studied were aluminum alloys 2024 and 6061, brass, copper, inconel alloys 625 and 718, Stainless Steel 304, tantalum, titanium, and tungsten. The ion beams studied consisted of protons at energies of 6, 12, and 19 MeV, Lithium-7 at energies of 10, 15, 20, and 30 MeV; Lithium-6 at 30 MeV; and Boron-10 and Boron-11 at 30 MeV. The induced activity of each sample was measured as a function of time with an ion chamber and was used to estimate the rate at which the initial short-lived activity of the sample decayed. In addition, the activity of each sample was periodically measured with a Geiger counter in contact with the irradiated surface of the sample, was normalized to the total amount of energy incident on the sample, and was used as a basis to compare the amount of activity generated per mega-joule of energy for each sample. Additionally, gamma-ray spectra of the activated samples were collected using a germanium detector, and these spectra were analyzed qualitatively to identify the long-lived radioisotopes present in the sample. Future work will also be discussed

1993-06-07

212

Indução à ovulação pelo uso de LHRH análogo e fertilização artificial em rã-touro (Rana catesbeiana) Spawning inducing by analog LHRH and artificial fertilization of bullfrog (Rana catesbeiana)  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Este trabalho teve por objetivo aperfeiçoar a técnica de reprodução induzida existente para rã-touro, com o intuito de aumentar a taxa de fecundidade e viabilizar seu uso pelo produtor. As doses hormonais para a indução da ovulação e espermiação seguiram as propostas de FALCON e CULLEY (1995) e ALONSO (1997); entretanto, a técnica de fertilização artificial foi adaptada da metodologia para reprodução artificial de peixes com ovos não-aderentes (WOYNAROVICH e HORVÁTH, 1983). ...

2000-01-01

213

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

1994-04-24

214

Artificial hand:  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

Wisse, M.; Wilbers, F.; Meijneke, C.

2011-01-01

215

Artificial Gravity  

CERN Multimedia

Protecting the health, safety, and performance of exploration-class mission crews against the physiological deconditioning resulting from long-term weightlessness during transit and long-term reduced gravity during surface operations will require effective, multi-system countermeasures. Artificial gravity, which would replace terrestrial gravity with inertial forces generated by rotating the transit vehicle or by short-radius human centrifuge devices within the transit vehicle or surface habitat, has long been considered a potential solution. However, despite its attractiveness as an efficient

Clément, Gilles

2007-01-01

216

Radioactive decay  

International Nuclear Information System (INIS)

A comprehensive study of the radioactive decay which plays a significant role in most chemical applications of isotopes is presented. First the kinetics, then the different kinds and mechanisms of radioactive processes are dealt with (disintegration of radioactive mixtures, branching decays, radioactive equilibrium, isotope dating techniques, alpha, beta, and photon and neutron decay, electron capture, spontaneous fission, isomeric transitions, etc.)

1987-01-01

217

Monitoring of peptide induced disruption of artificial lipid membrane constructed on boron-doped nanocrystalline diamond by electrochemical impedance spectroscopy  

Digital Repository Infrastructure Vision for European Research (DRIVER)

With the rise of antibiotic resistance of pathogenic bacteria there is an increased demand for monitoring of the functionality of bacteria membranes, whose disruption can be induced by peptide lipid interactions. In this work we attempt to monitor formation and subsequent peptide induced disruption of supported lipid membranes (SLBs) on boron-doped nanocrystalline diamond (B-NCD). Electrochemical Impedance Spectroscopy (EIS) was used to study in situ changes related to lipid membrane formatio...

Petrak, Vaclav; Grieten, Lars; Taylor, Andrew; Fendrych, Frantisek; Ledvina, Miroslav; Janssens, Stoffel D.; Nesladek, Milos; Haenen, Ken; Wagner, Patrick

2011-01-01

218

Customs control of radioactive materials  

International Nuclear Information System (INIS)

Customs officers take part in the combat against illicit traffic od radioactive materials by means of different regulations dealing with nuclear materials, artificial radiation sources or radioactive wastes. The capability of customs officers is frequently incomplete and difficult to apply due to incompatibility of the intervention basis. In case of contaminated materials, it seems that the customs is not authorised directly and can only perform incidental control. In order to fulfil better its mission of fighting against illicit traffic of radioactive materials customs established partnership with CEA which actually includes practical and theoretical training meant to augment the capabilities of customs officers

1998-09-01

219

Electrically induced large-amplitude vibration and resonance characteristics on ionic polymeric membrane-metal composites artificial muscles  

Science.gov (United States)

This research identifies key parameters involving the vibrational characteristics of actuators made of ion-exchange- membrane-metal composites. These actuators are made from commercially available ion-exchange membranes chemically treated with platinum to produce composite actuators that are highly deformable in the presence of low amplitude electrical field. They show remarkable bending displacement that follow input signal very closely. When the applied signal frequency is varied, so does the displacement up to a point where large deformations are observed at a critical frequency called resonant frequency where maximum deformation is observed. Beyond which the actuator response is diminished. In this research paper, several samples of the actuators were made and tested with various dimensions to compare the vibrational behavior of the actuators. A data acquisition system was used to measure the parameters involved and record the results in real time basis. This research was in support of active vibration suppression research for flexible structures using ionic polymers as active dampers. It also supported other applications in biomimetics research such as bird flight motion, artificial coral reefs and marine propulsion.

Shahinpoor, Mohsen; Mojarrad, Mehran; Salehpoor, Karim

1997-06-01

220

The effect of Amaranth oil on monolayers of artificial lipids and hepatocyte plasma membranes with adrenalin-induced stress.  

Science.gov (United States)

In this paper the oil from seeds of Amaranthus cruentus L. (AmO) was shown to be an efficient modulator of the physical chemical properties of artificial lipid and rat hepatocyte plasma membranes. AmO improved the membrane stability, their stress resistance and the adsorption of neurotensin to plasma membranes with the distinct biphasic interactions being observed even after adrenalin stress exposure. The analysis of pro-/antioxidant balance in rat blood revealed a mild prooxidant activity after AmO intake, which was accompanied by accumulation of oxidative destruction products in plasma membranes. This prooxidant action of AmO was corroborated in vitro in an adrenalin autooxidation model. On the other hand, the observed improved resistance to adrenalin stress in AmO supplemented rats was associated with an antioxidant response in blood and plasma membrane studies. The AmO effects can be attributed to the modulation of the metabolic pathways involved into oxygen and free radical homeostasis. PMID:24206699

Yelisyeyeva, O P; Semen, K O; Ostrovska, G V; Kaminskyy, D V; Sirota, T V; Zarkovic, N; Mazur, D; Lutsyk, O D; Rybalchenko, K; Bast, A

2014-03-15

 
 
 
 
221

Analysis of induced-radioactivity using DCHAIN-SP for Pb and Hg at a mercury target irradiated by 2.8 and 24 GeV protons  

International Nuclear Information System (INIS)

The high energy particle induced radioactivity calculation code system consisting PHITS, MCNP4C and DCHAIN-SP 2001 was validated for mercury and lead samples by the experimental activation data obtained using AGS (Alternative Gradient Synchrotrons) accelerator at Brookhaven National Laboratory. As a result, we found that the calculation is consistent with the experimental data within a factor of 2 on the average. Mass yield curves of the spallation reactions were approximately deduced using the experimental activation data. (author)

2006-11-01

222

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)

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

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

223

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)

2008-08-12

224

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)

2008-08-12

225

Artificial Neural Network Modeling of Healthy Risk Level Induced by Aircraft Pollutant Impacts around Soekarno Hatta International Airport  

Directory of Open Access Journals (Sweden)

Full Text Available Aircraft pollutant emissions are an important part of sources of pollution that directly or indirectly affect human health and ecosystems. This research suggests an Artificial Neural Network model to determine the healthy risk level around Soekarno Hatta International Airport-Cengkareng Indonesia. This ANN modeling is a flexible method, which enables to recognize highly complex non-linear correlations. The network was trained with real measurement data and updated with new measurements, enhancing its quality and making it the ideal method for this research. Measurements of aircraft pollutant emissions are carried out with the aim to be used as input data and to validate the developed model. The obtained results concerned the improved ANN architecture model based on pollutant emissions as input variables. ANN model processes variables—hidden layers—and gives an output variable corresponding to a healthy risk level. This model is characterized by a 4-10-1 scheme. Based on ANN criteria, the best validation performance is achieved at epoch 28 from 34 epochs with the Mean Squared Error (MSE of 9 × 10-3. The correlation between targets and outputs is confirmed. It validated a close relationship between targets and outputs. The network output errors value approaches zero. Further research is needed with the aim to enlarge the scheme of the ANN model by increasing its input variables. This is one of the major key defining environmental capacities of an airport that should be applied by Indonesian airport authorities. These would institute policies to manage or reduce pollutant emissions considering population and income growth to be socially positive.

Salah Khardi

2013-07-01

226

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

Directory of Open Access Journals (Sweden)

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.

W.-B. Chen

2012-12-01

227

Environmental radioactivity annual report 1994  

International Nuclear Information System (INIS)

During 1994 artificial radioactivity in the environment in New Zealand and Rarotonga continued to be at trace level only, typical of recent years. There has been no significant change in artificial radioactivity status of the environment. Atmospheric and deposited radioactivity was monitored at Kaitaia, Hokitika and Rarotonga and milk radioactivity was monitored in Auckland, Taranaki and Westland. Average levels measured were: total beta activity in air, 0.13 mBq/m3; 90Sr deposition, 0.2 ± 0.2 Bq/m2; 137Cs in milk, 0.08 Bq/g K; 90Sr in milk, 0.02 Bq/g Ca. Total beta activity depositions at Hokitika and Rarotonga were 213 Bq/m2 and 174 Bq/m2 respectively. Annual total 210Pb depositions at Kaitaia, Hokitika and Rarotonga were 44, 124 Bq/m2 respectively. No artificial radionuclides were detected by gamma spectroscopic analysis of high-volume air filters during 1994, with weekly sampling periods. Annual average atmospheric 137Cs concentrations, assessed by analysis of yearly air filter aggregates, at the New Zealand and Rarotonga monitoring sites were 0.04 ± 0.02 and 0.03 ± 0.02 ?Bq/m3 respectively. Average atmospheric concentrations of natural 7Be and 210Pb were 3.1 and 0.07 mBq/m3 respectively. The report includes data on trends in atmospheric radioactivity levels since 1987. (author). 8 refs., 5 tabs., 3 figs

228

Teaching radioactivity  

...Teaching radioactivity Teaching radioactivity This site uses cookies. By continuing to use this site you agree to our use of cookies. To ...are here Education I am a teacher Resources for the classroom Teaching radioactivity I am a teacher Resources for the classroom Practical Physics Teaching ...Qualification (EPQ) in physics Teaching astronomy and space Teaching Medical Physics Teaching radioactivity Physics in Concert Voicebox: The Physics and Evolution of Speech ...SimPhysics The MODEL Project Other IOP resources Teaching radioactivity The Institute has produced a number of resources to support the teaching of radioactivity. ...

229

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

Digital Repository Infrastructure Vision for European Research (DRIVER)

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...

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

2008-01-01

230

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.)

2014-01-01

231

Artificial Economy  

Directory of Open Access Journals (Sweden)

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.

Alexandru JIVAN

2011-08-01

232

Natural radioactivity  

International Nuclear Information System (INIS)

This chapter discusses the types of natural radioactive materials in the environment that include primordial natural radioactive materials such as K-40, U and Th, and daughters of their decay series. The discussion also includes secondary natural radioactive material generated through cosmic radiation interaction with nucleus of materials in the atmosphere. The dispersion of these radioactive materials to environment will also be part of the discussion. (Author)

2005-01-01

233

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.)

1980-01-01

234

Artificial insemination in the anoestrous and the postpartum white rhinoceros using GnRH analogue to induce ovulation.  

Science.gov (United States)

The objective of this study was to develop AI and to achieve first time pregnancy in a nulliparous rhinoceros. For this, one 24-year-old irregular cycling female white rhinoceros was selected, which had never been mated. The endocrine function was monitored by faecal and serum pregnane analysis. Ultrasound determined the optimal day for AI by measuring follicle sizes of 2.0, 2.6, 3.0, 3.2 cm on days -6, -4, -1, 0 of the induced oestrous cycle, respectively. AI was performed and ovulation induced when a pre-ovulatory-sized follicle was present using GnRH analogue, deslorelin. Fresh semen was deposited in the uterine horn using a patented AI catheter overcoming the hymeneal membrane and torturous cervical folds non-surgically. Moreover, ultrasound monitoring of the uterine involution and ovarian activity on days 16, 26, 30 postpartum facilitated the induction of and the AI on the first postpartum oestrous in a rhinoceros using GnRH analogue. Two consecutive pregnancies were achieved by AI for the first time in the rhinoceros. Pregnancies were diagnosed by elevated serum and faecal 20-oxo-pregnane concentrations. In addition ultrasound measured biometric parameters of the two foetuses on days 86 and 133 of gestation. Two female calves were born after 490 and 502 days of gestation, yet one calf was stillborn. AI in rhinoceros might now be used as assisted reproduction technology tool to boost critically small captive rhinoceros populations. PMID:17451805

Hildebrandt, T B; Hermes, R; Walzer, C; Sós, E; Molnar, V; Mezösi, L; Schnorrenberg, A; Silinski, S; Streich, J; Schwarzenberger, F; Göritz, F

2007-06-01

235

Radioactive wastes  

International Nuclear Information System (INIS)

This study of general interest is an evaluation of the safety of radioactive waste management and consequently the preservation of the environment for the protection of man against ionizing radiations. The following topics were developed: radiation effects on man; radioactive waste inventory; radioactive waste processing, disposal and storage; the present state and future prospects

1988-01-01

236

ULF waves with drift resonance and drift-bounce resonance energy sources as observed in artificially-induced HF radar backscatter  

Directory of Open Access Journals (Sweden)

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 been demonstrated to provide ionospheric electric field data of unprecedented temporal resolution and accuracy. Here such data are used to investigate ULF wave processes observed by the CUTLASS HF radars. Within a short period of time during a single four hour experiment three distinct wave types are observed with differing periods, and latitudinal and longitudinal phase evolution. Combining information from the three waves allows them to be divided into those with a large-scale nature, driven externally to the magnetosphere, and those with small azimuthal scale lengths, driven by wave-particle interactions. Furthermore, the nature of the wave-particle interactions for two distinct small-scale waves is revealed, with one wave interpreted as being driven by a drift resonance process and the other by a drift-bounce resonance interaction. Both of these mechanisms with m ? -35 and proton energies of 35–45 keV appear to be viable wave energy sources in the postnoon sector.

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

T. K. Yeoman

237

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

Energy Technology Data Exchange (ETDEWEB)

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 ({sup 3}H)QNB, and also the activities of both acetylcholinesterase and choline acetyltransferase.

Serbus, D.C.

1988-01-01

238

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)

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.

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

239

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.

2013-01-01

240

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

Energy Technology Data Exchange (ETDEWEB)

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.

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

 
 
 
 
241

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.)

1980-01-01

242

The artificial heart  

...The artificial heart topic moment artificial heart IOP physics A patient heading home after being given an artificial heart has made news headlines. ...Careers Policy Resources You are here Resources Topic of the moment Archive Artificial heart Topic of the moment Archive Antimatter The Apollo programme Archeology ...Fiction to fact Fuel cells Geolocation Graphene The career of Stephen Hawking Artificial heart Herschel Space Observatory Higgs boson Metamaterials Meteor and asteroid impacts ...sport Television Transit of Venus Volcanic ash Weights and measures cryptography The artificial heart A patient heading home after being given an artificial heart ...

243

Environmental radioactivity annual report 1991  

International Nuclear Information System (INIS)

During 1991 artificial radioactivity in the environment in New Zealand and Rarotonga continued to be at a trace level only, typical of recent years. There has been no significant change in artificial radioactivity levels since 1990. Average levels measured were: total beta activity in air, 0.11 mBq/m3; 90Sr deposition, 0.2 Bq/km2; 137Cs in milk, 0.2 Bq/gK; 90Sr in milk, 0.03 Bq/gCa. Total beta activity depositions at Hokitika and Rarotonga were 240 Bq/km2 and 73 Bq/km2 respectively. Atmospheric and deposited radioactivity were due primarily to 210Pb. No artificial radionuclides were detected on high-volume air filters during 1991. The report includes data on trend in natural atmospheric radioactivity level during the year. Average concentrations of 7Be and 210Pb, were 2.7 mBq/m3 and 0.05 mBq/m3 respectively. (author). 8 refs., 4 figs., 2 tabs

1992-01-01

244

An abstracted model for assessing the effect of seismically induced rockfall on the waste package performance for high-level radioactive waste disposal  

International Nuclear Information System (INIS)

Failure of the waste package (WP) from seismically induced rockfall is considered one of the processes that could affect the performance of a repository for high-level radioactive waste disposal. Rockfall could rupture a WP directly from impact or could damage it in a manner that will accelerate corrosion and reduce the intended service life of the WPs. This paper presents the U.S. Nuclear Regulatory Commission's abstracted conceptual model for investigating the consequence of rockfall on WP integrity and demonstrates performance assessment capability using a U.S. Department of Energy repository design concept. (author)

2000-12-01

245

Neutron activation analysis for long-lived induced radioactivity investigations of concretes used in nuclear reactor shielding constructions  

International Nuclear Information System (INIS)

Elementary content in aggregates of shielding concretes (portlandcement, gabbro, sand, granite, hematite, limestone) was investigated to reveal nuclides mainly contributing into long-lived radioactivity of concretes used in nuclear reactors by neutron activation analysis at the IBR-2 reator of the LNP of JINR. It is shown that the nuclides mainly responsible for the long-lived radioactivity are 152Eu, 154Eu, 60Co and 134Cs. Calculations of the specific radioactivity of aggregates after irradiation fo 30 years by the neutron flux of unit density have been done on the basis of the experimental data. The dependences of the specific radioactivity versus time are presented graphically. Restructions on the use of such aggregates as magnetite, chromite, serpentinite in shielding constructions are recommended. The estimations of the dose rate from the concrete construction containing different aggregates in the approximation of semifinite space are given. The obtained results can serve as basis for the optimal choose of aggregates in concretes for nuclear set-up shielding constructions

1988-01-01

246

Artificial radioelements; Radioelements artificiels  

Energy Technology Data Exchange (ETDEWEB)

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, {gamma}) 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.) [French] Ce catalogue detaille la liste des radioelements artificiels obtenus a la Pile ZOE. un certain nombre de methodes de concentration et de separation ont ete mises au point. Les cibles sont soumis a irradiation dans un flux de neutron thermique en vue d'obtenir par reaction neutronique les radioelements desires. Dans le cas de la reaction (n,p), l'element radioactif est separe chimiquement afin de produire des radioelements ''sans entraineur''. Pour les radioelements issus de la reaction (n, {gamma}) on utilise l'Effet de Szilard et Chalmers pour separer les atomes actifs et inactifs afin d'augmenter l'activite specifique du radioelement d'interet. (M.B.)

NONE

1952-07-01

247

Analysis of induced-radioactivity using DCHAIN-SP for iron, copper and niobium at a mercury target irradiated by 2.83 and 24 GeV protons  

International Nuclear Information System (INIS)

Reliability estimation was carried out on a radioactivity calculation code system consisting of PHITS, MCNP/4C and DCHAIN-SP 2001 by analyzing an activation experiment performed by using AGS (Alternative Gradient Synchrotron) accelerator at Brookhaven National Laboratory. For induced radioactivity in iron, copper and niobium samples, calculations and experiments were compared indicating that both agreed by a factor of 2 on the average over produced nuclides although the calculation had a tendency to underestimate. (author)

2006-11-01

248

Radioactivity Handbook  

International Nuclear Information System (INIS)

The Radioactivity Handbook will be published in 1985. This handbook is intended primarily for applied users of nuclear data. It will contain recommended radiation data for all radioactive isotopes. Pages from the Radioactivity Handbook for A = 221 are shown as examples. These have been produced from the LBL Isotopes Project extended ENDSF data-base. The skeleton schemes have been manually updated from the Table of Isotopes and the tabular data are prepared using UNIX with a phototypesetter. Some of the features of the Radioactivity Handbook are discussed here

1985-05-01

249

The artificial endothelium.  

Science.gov (United States)

As the world of critical care medicine advances, extracorporeal therapies (ECC) have become commonplace in the management of the high risk intensive care patient. ECC encompasses a wide variety of technologies from hemodialysis, continuous renal replacement therapy (CRRT) and plasmapheresis, to cardiopulmonary bypass (CPB), extracorporeal life support (ECLS) and hepatic support. The development of internal man made organs is the next step with ventricular assist devices and artificial lungs. As we advance the technologies with smaller devices, and more intricate circuitry, we lack the keystone necessary to control the blood-biomaterial interface. For the last 50 years much has been learned about surface induced thrombosis and attempts have been made to prevent it with alternative systemic anticoagulation, circuitry surface modifications, or a combination of both. Despite these efforts, systemic or regional anticoagulation remain necessary for both laboratory and clinical application of ECC. As such, the development of an endothelial-like, biomimetic surface to reduce or perhaps even eliminate the blood activation/thrombus formation events that occur upon exposure to artificial surfaces is paramount. PMID:21289481

Reynolds, Melissa M; Annich, Gail M

2011-01-01

250

Transmutation of radioactive wastes: how and why?  

International Nuclear Information System (INIS)

After having evoked the natural or spontaneous transmutation of natural or artificial radioactive atoms, the author describes how this transmutation is technically obtained, indicates the two main families of atoms present in a used nuclear fuel and for which transmutation is to be investigated (long-lived fission residues or products, and transuranium elements) and of which the behaviour in neutron fluxes must be explored. He discusses the industrial means required for artificial transmutation. He discusses the interest of performing such a transmutation

2004-01-01

251

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.)

1980-01-01

252

Environmental radioactivity annual report 1988  

International Nuclear Information System (INIS)

Artificial radioactivity in the environment in New Zealand and Rarotonga during 1988 continued to be at a trace level only, typical of recent years. Average levels were: total beta activity in air, 0.08 mBq/m3; strontium-90 deposition, 0.1 MBq/km2; caesium-137 in milk, 0.18 Bq/gK; strontium-90 in milk, 0.041 Bq/gCa. No artificial radionuclides were detected on high-volume air filters. Total beta activity deposition at Hokitika was higher than usual at 336 MBq/km2, and this is thought to be due to heavy deposition of natural radioactivity during heavy spring rains. Strontium-90 deposition was the lowest since measurements began in 1960, and was virtually undetectable. The report includes monitoring data for natural beryllium-7 including plots of variations in atmospheric concentration during 1987 and 1988. (author). 9 refs., 9 figs., 2 tabs

1989-01-01

253

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)

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)

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

1963-11-15

254

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)

1980-01-01

255

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

Directory of Open Access Journals (Sweden)

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.

C. Bes

2013-07-01

256

Defects induced by electron irradiation in hollandite ceramics, specific radioactive cesium-host wasteforms: a 57Fe Moessbauer study  

International Nuclear Information System (INIS)

Several single phase hollandite ceramics having Ba2+xCs+y(C Al,Fe)3+2x+yTi4+8-2x-yO16 composition have been synthesized and irradiated under external electron beams simulating the ?-irradiation of radioactive cesium. These samples have been characterized by 57Fe transmission Moessbauer spectroscopy. Moessbauer results show that the irradiation modifies the local arrangements of Ba cations around Fe3+ ions by atomic displacement of Ba ions.

2005-11-01

257

Environmental radioactivity annual report 1992  

International Nuclear Information System (INIS)

During 1992 artificial radioactivity in the environment in New Zealand and Rarotonga continued to be at a trace level only, typical of recent years. There has been no overall change in artificial radioactivity levels since 1991. Average levels were: total beta activity in air, 0.14 mBq/m3; 90Sr deposition, 0.1 Bq/km2; 137Cs in milk, 0.2 Bq/gK; 90Sr in milk, 0.03 Bq/gCa. Total beta activity depositions at Hokitika and Rarotonga were 149 Bq/km2 and 214 Bq/km2 respectively. No artificial radionuclides were detected by gamma spectroscopic analysis of high-volume air filters during 1992. Average atmospheric concentrations of natural 7Be and 210Pb were 2.9 mBq/m3 and 0.06 mBq/m3 respectively. The report includes data on trends in atmospheric radioactivity levels since 1987. Atmospheric 7Be levels appear to have been following a downward trend since 1988; atmospheric beta activity has been increasing slowly since 1990; while atmospheric 210Pb levels have been relatively constant since measurements began in 1989. (author). 13 refs., 3 tabs., 4 figs

1993-01-01

258

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

259

Forest decline, natural and technically generated radioactivity  

International Nuclear Information System (INIS)

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

1983-01-01

260

Purification of highly-radioactive mouse interferon produced by Ehrlich ascites tumour cells induced by Sendai virus  

Energy Technology Data Exchange (ETDEWEB)

Mouse interferon (IFN) was produced to high titres after induction of Ehrlich ascites tumour cells with Sendai virus by using an improved procedure. The IFN molecules were labelled during their synthesis by the incorporation of (/sup 3/H)leucine and (/sup 3/H)lysine. Electrophoretically homogeneous labelled IFN with a molecular weight of 34000 was obtained after a two-step purification procedure using poly(I)-agarose and octyl-Sepharose column chromatography followed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis. The specific radioactivity of this IFN was about 10 ct/min/IFN unit.

Dussaix, E.; Gregoire, A.; Chany, C. (Institut National de la Sante et de la Recherche Medicale (INSERM), Hopital Saint Vincent-de-Paul, Paris (France)); Thang, D.C.; Thang, M.N. (Paris-6 Univ., 75 (France). Inst. de Biologie Physico-Chimique)

1983-02-01

 
 
 
 
261

Defects induced by electron irradiation in hollandite ceramics, specific radioactive cesium-host wasteforms: a {sup 57}Fe Moessbauer study  

Energy Technology Data Exchange (ETDEWEB)

Several single phase hollandite ceramics having Ba{sup 2+}{sub x}Cs{sup +}{sub y}(C Al,Fe){sup 3+}{sub 2x+y}Ti{sup 4+}{sub 8-2x-y}O{sub 16} composition have been synthesized and irradiated under external electron beams simulating the {beta}-irradiation of radioactive cesium. These samples have been characterized by {sup 57}Fe transmission Moessbauer spectroscopy. Moessbauer results show that the irradiation modifies the local arrangements of Ba cations around Fe{sup 3+} ions by atomic displacement of Ba ions.

Nguyen, N.; Ducouret, A.; Studer, F., E-mail: francis.studer@ensicaen.fr [CRISMAT (CNRS-UMR 6508), ENSICAEN (France); Aubin, V.; Caurant, D.; Gourier, D. [LCAES (CNRS UMR 7574) (France); Costantini, J.-M. [CEA/DMN/SRMA (France)

2005-11-15

262

Biomechanical characterization and clinical implications of artificially induced toe-walking: differences between pure soleus, pure gastrocnemius and combination of soleus and gastrocnemius contractures.  

Science.gov (United States)

The purpose of this study was to characterize biomechanically three different toe-walking gait patterns, artificially induced in six neurologically intact subjects and to compare them to selected cases of pathological toe-walking. The subjects, equipped with lightweight mechanical exoskeleton with elastic ropes attached to the left leg's heel on one end and on shank and thigh on the other end in a similar anatomical locations where soleus and gastrocnemius muscles attach to skeleton, walked at speed of approximately 1m/s along the walkway under four experimental conditions: normal walking (NW), soleus contracture emulation (SOL), gastrocnemius contracture emulation (GAS) and emulation of both soleus and gastrocnemius contractures (SOLGAS). Reflective markers and force platform data were collected and ankle, knee and hip joint angles, moments and powers were calculated using inverse dynamic model for both legs. Characteristic peaks of averaged kinematic and kinetic patterns were compared among all four experimental conditions in one-way ANOVA. In the left leg SOL contracture mainly influenced the ankle angle trajectory, while GAS and SOLGAS contractures influenced the ankle and knee angle trajectories. GAS and SOLGAS contractures significantly increased ankle moment during midstance as compared to SOL contracture and NW. All three toe-walking experimental conditions exhibited significant power absorption in the ankle during loading response, which was absent in the NW condition, while during preswing significant decrease in power absorption as compared to NW was seen. In the knee joint SOL contracture diminished, GAS contracture increased while SOLGAS contracture approximately halved knee extensor moment during midstance as compared to NW. All three toe-walking experimental conditions decreased hip range of motion, hip flexor moment and power requirements during stance phase. Main difference in the right leg kinematic and kinetic patterns was seen in the knee moment trajectory, where significant increase in the knee extensor moment took place in terminal stance for GAS and SOLGAS experimental conditions as compared to SOL and NW. The kinetic trajectories under SOL and GAS experimental conditions were qualitatively compared to two selected clinical cases showing considerable similarity. This implies that distinct differences in kinetics between SOL, GAS and SOLGAS experimental conditions, as described in this paper, may be clinically relevant in determining the relative contribution of soleus and gastrocnemius muscles contractures to toe-walking in particular pathological gait. PMID:16321627

Matjaci?, Zlatko; Olensek, Andrej; Bajd, Tadej

2006-01-01

263

On Radioactivity–Exposed Nanophotodetector Optoreliability  

Digital Repository Infrastructure Vision for European Research (DRIVER)

The optoelectronic reliability of representative radioactivity-exposed nanophotodetectors and the degree of functionally tolerable radioactivity-induced responsivity de-emphasis, against increasing cumulative radioactivity-dose, is notionally considered and modelled, with a view towards experimental findings concerning p-i-n photosensors being exposed to regulated successive (?, ?)-particle bombardments.

Anagnostakis, Emmanuel A.

2011-01-01

264

On Radioactivity–Exposed Nanophotodetector Optoreliability  

Directory of Open Access Journals (Sweden)

Full Text Available The optoelectronic reliability of representative radioactivity-exposed nanophotodetectors and the degree of functionally tolerable radioactivity-induced responsivity de-emphasis, against increasing cumulative radioactivity-dose, is notionally considered and modelled, with a view towards experimental findings concerning p-i-n photosensors being exposed to regulated successive (?, ?-particle bombardments.

Emmanuel A. Anagnostakis

2011-07-01

265

Cluster radioactivity  

International Nuclear Information System (INIS)

The phenomenon of spontaneous emission of nuclei intermediate in mass between alpha particles and fission fragments is known as cluster radioactivity (CR) or exotic radioactivity. The process of emission of clusters heavier than alpha particles is called cluster decay or exotic decay. This process is not accompanied by emission of neutron. The CR phenomenon was first predicted in 1980 by Sandulescu et al on the basis of quantum mechanical fragmentation theory (QMFT). Theoretical model-1. Alpha-decay like models 2. Fission like models will be discussed in this talk. And also it is associated with present scenario cluster radioactivity exhibited by some isotopes of Gadolinium (Gd), Z=64. (author)

2012-01-01

266

Advances in artificial lungs.  

Science.gov (United States)

Artificial lungs have already been developed as complete artificial organs, and results of many investigations based on innovative concepts have been reported continuously. In open-heart surgery, artificial lungs are used for extracorporeal circulation to maintain gas exchange, and the commercial products currently available perform adequately, including providing for antithrombogenicity. However, patients after cardiopulmonary arrest or severe respiratory/circulatory failure have required long-term assist with extracorporeal membrane oxygenation (ECMO). The number of artificial lungs used for ECMO in those cases has shown significant growth in recent years. Therefore, it is expected that durability and antithrombogenicity will ensure the prolonged use of an artificial lung for several weeks or months. Furthermore, interests in research are shifting to use of oxygenators as a bridge to lung transplantation and an implantable artificial lung. This paper discusses recent advances in artificial lungs, focusing on the current state and on trends in research and development. PMID:20177723

Ota, Kei

2010-04-01

267

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

2009-01-00

268

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

Directory of Open Access Journals (Sweden)

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.

Van So Le

2011-01-01

269

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

1995-08-01

270

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)

1990-01-01

271

The radioactivity of the sea  

Energy Technology Data Exchange (ETDEWEB)

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, {sup 40}K, 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).

Walker, M.I.; Rose, K.S.B. (AEA Enviroment and Energy, Harwell (UK). Environmental Safety Div.)

1990-08-01

272

Simulated Radioactivity  

Science.gov (United States)

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

Boettler, James L.

1972-01-01

273

Concentrating Radioactivity  

Science.gov (United States)

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

Herrmann, Richard A.

1974-01-01

274

Radioactivity Calculations  

Science.gov (United States)

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

Onega, Ronald J.

1969-01-01

275

Measurement of radioactivity in steel  

International Nuclear Information System (INIS)

Even after the control of scrap deliveries, there remains a small risk that the radioactive contaminated scrap passes the detecting devices. Therefore, the chemical laboratory takes a role to measure each heat for the absence of artificial radioactive nuclides with a gamma spectrometer equipped with NaI-detector. As the measurement must be performed in sequence with the steel production process, the allowable time for the measurement is quite limited. On the other hand, there could be still some possibility that background radiation might be present as the samples may contain some natural radioactivity. The task is how to differentiate the nature of radioactivity between naturally remaining radioactivity within safe limit and artificial nuclides present in the sample at a low level even though a very small amount of radioactivity could be detected in short time in both cases. We have set the alarm limit to 0.1 Bq/g for Co-60 as indicating nuclide. This limit is set more than 4 s (s = standard deviation) from the average background radiation. Therefore, false alarms are quite improbable. Strategy: The NaI gamma spectrometer performs a gross gamma measurement but it can not differentiate the nature of the nuclides present. If the alarm limit is hurt, the sample is measured on a high resolution gamma spectrometer with Ge-detector for identification of the gamma emitting nuclides. Calibration: Even though no appropriate international standards are adapted and no commercial measuring equipment is commercially available, the desired standard should contain Co-60 in the order of 1 to 100 Bq/g. The presence of other gamma emitting nuclides is desirable. In the Workshop we will present how to surmount this difficulty. (author)

1999-05-26

276

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  

Energy Technology Data Exchange (ETDEWEB)

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 {sup 152}Eu, {sup 154}Eu and {sup 155}Eu and {sup 60}Co were measured for recent and old europium and cobalt reagents. Observed activities are 0.06-0.52 dpm g{sup -1} for {sup 152}Eu, 0.09-0.16 dpm g{sup -1} for {sup 154}Eu and 0.005-0.16 dpm g{sup -1} for {sup 155}Eu and 0.007-0.083 dpm g{sup -1} for {sup 60}Co. Contribution of natural {sup 152}Eu and {sup 60}Co in Atomic-bomb exposed samples are found to be negligible low and less than 10%, respectively. (author)

Komura, Kazuhisa [Kanazawa Univ., Low Level Radioactivity Lab., Tatsunokuchi, Ishikawa (Japan); Yousef, Ahmed M. [South Valley Univ. (Egypt)

2001-06-01

277

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)

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)

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

278

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)

2002-01-01

279

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

1990-01-01

280

High-energy proton irradiation and induced radioactivity analysis for some construction materials for the CERN LHC  

International Nuclear Information System (INIS)

The dose rate to personnel due to remnant radioactivity during maintenance periods will be an important issue at the forthcoming Large Hadron Collider (LHC). Among the most abundant construction materials are aluminum, steel, copper and lead. In order to obtain more reliable estimates on the radioisotope production in a high-energy hadron environment, small samples of these materials behind the beam-stop of the CERN 24 GeV/c proton synchrotron were irradiated. This environment is characterized by high spallation neutron flux and a non-negligible contribution of protons and pions up to the total beam momentum. Gamma-ray spectra of the samples were measured and analyzed with the SAMPO program and detailed nuclide identification was carried out with the SHAMAN program. The total energy emission and results of the spectrum analyses were compared to predictions of the FLUKA hadron cascade simulation package. (author)

2005-04-01

 
 
 
 
281

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

1995-01-01

282

Environmental radioactivity in New Zealand and Rarotonga : annual report 2010  

International Nuclear Information System (INIS)

The atmosphere was monitored for radioactivity at Kaitaia, Rarotonga and Chatham Islands; deposited radioactivity was monitored at Hokitika (through rainwater testing); and radioactivity in milk was monitored in the Waikato, Taranaki and Westland regions. Any artificial radioactivity continued to be at levels which are below detection thresholds in many cases and significantly below levels which would give rise to health concerns. This continues the trend of recent years, and confirms there has been no significant change in the radioactivity status of the environment. (author). 6 refs., 2 tabs.

2011-01-01

283

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)

1981-01-01

284

Artificial cognition architectures  

CERN Multimedia

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

Crowder, James A; Friess, Shelli A

2013-01-01

285

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)

2005-08-01

286

Artifacts and Artificial Science  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 p...

Beckman, Svante; Nilsson, Go?ran B.; Dahlbom, Bo

2002-01-01

287

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

1993-08-08

288

Radioactivity monitoring in Ireland of air, deposition and water 1982-1987  

International Nuclear Information System (INIS)

The Nuclear Energy Board in conjunction with the Meteorological Service undertakes an environmental radioactivity monitoring programme with the objective of determining levels of artificially produced radioactivity in the Irish environment. The levels of radioactivity in airbourne dust, total fallout samples, precipitation and drinking water are presented for 1982, 1983, 1984, 1985, 1986 and 1987

1989-01-01

289

Environmental radioactivity annual report 1989  

International Nuclear Information System (INIS)

During 1989 artificial radioactivity in the environment in New Zealand and Rarotonga continued to be at a trace level only, typical of recent years. There has been no significant change in artificial radioactivity levels since 1988. Average levels were: total beta activity in air, 0.09 mBq/m3; Sr deposition, 0.1 MBq/km3; 137Cs in milk, 0.19 Bq/gK; 90Sr in milk, 0.041 Bq/gCa. Total beta activity depositions at Hokitika and Rarotonga were 264 MBq/km2 and 88 MBq/km2 respectively. No artificial radionuclides were detected on high-volume air filters. The report provides atmospheric monitoring data for natural 7Be and 210Pb, including plots of variations in concentration during the year. Average concentrations of 7Be and 210Pb were 2.6 mBq/m3 and 0.06 m Bq/m3 respectively. Cumulative 137Cs deposition profiles are graphed for New Zealand monitoring sites, for the period 1955-1989. (author). 12 refs., 5 figs., 2 tabs

1990-01-01

290

Environmental radioactivity annual report 1990  

International Nuclear Information System (INIS)

During 1990 artificial radioactivity in the environment in New Zealand and Rarotonga continued to be at a trace level only, typical of recent years. There has been no significant change in artificial radioactivity levels since 1989. Average levels were: total beta activity in air, 0.09 mBq/m3; 90Sr deposition, 0.1 MBq/km2; 137Cs in milk, 0.14 Bq/gK; 90Sr in milk, 0.036 Bq/gCa. Total beta activity depositions at Hokitika and Rarotonga were 201 MBq/m2 and 80 MBq/m2 respectively. Atmospheric and deposited beta activity were due primarily to 210Pb. No artificial radionuclides were detected on high-volume air filters. The report provides atmospheric monitoring data for natural 7Be and 210Pb, including plots of variations in concentration during the year. Average concentrations of of 7Be and 216Pb were 2.6 mBq/m3 and 0.06 mBq/m3 respectively. (author). 9 refs., 4 figs., 2 tabs

1991-01-01

291

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

2007-01-01

292

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)

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.

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

2012-04-01

293

Radioactivity measurement  

International Nuclear Information System (INIS)

The radioactivity measurement in this chapter refers to nuclear analytical technique for the assessment of radioactivity in various type and form samples particularly the environmental and food samples. The following subjects are discussed: radionuclide measurement, sampling, radiochemical separation, sample preparation, radionuclide separation, source preparation, detection method - alpha counting, low background ?/? counting system, scintillation counter, alpha spectrometry, beta counting, photon counting, activity determination, statistical considerations, and quality assurance. The topic titled detection method, covers the principle, instrumentation, operational procedure and application for each method discussed

2005-01-01

294

Radioactive waste  

International Nuclear Information System (INIS)

The Environment Committee is appointed by the House of Commons to examine the expenditure, administration and policy of the Department of the Environment. In this case the subject is Radioactive Waste and this volume contains the appendices to the first report from the Environment Committee for the Session 1985-6. The appendices are mainly memoranda, or supplementary memoranda, from interested individuals, professional bodies, pressure groups, university departments etc. addressed to the Environment Committee. They are about all aspects of radioactive waste - monitoring, storage, disposal, transport, etc. (U.K.)

1986-01-01

295

Molecular recognition and organizational and polyvalent effects in vesicles induce the formation of artificial multicompartment cells as model systems of eukaryotes.  

Science.gov (United States)

Researchers have become increasingly interested in the preparation and characterization of artificial cells based on amphiphilic molecules. In particular, artificial cells with multiple compartments are primitive mimics of the structure of eukaryotic cells. Endosymbiotic theory, widely accepted among biologists, states that eukaryotic cells arose from the assembly of prokaryotic cells inside other cells. Therefore, replicating this process in a synthetic system could allow researchers to model molecular and supramolecular processes that occur in living cells, shed light on mass and energy transport through cell membranes, and provide a unique, isolated space for conducting chemical reactions. In addition, such structures can serve as drug delivery systems that encapsulate both bioactive and nonbiocompatible compounds. In this Account, we present various coating, incubation, and electrofusion strategies for forming multicompartment vesicle systems, and we are focusing on strategies that rely on involving molecular recognition of complementary vesicles. All these methods afforded multicompartment systems with similar structures, and these nanoparticles have potential applications as drug delivery systems or nanoreactors for conducting diverse reactions. The complementarity of interacting vesicles allows these artificial cells to form, and the organization and polyvalency of these interacting vesicles further promote their formation. The incorporation of cholesterol in the bilayer membrane and the introduction of PEG chains at the surface of the interacting vesicles also support the structure of these multicompartment systems. PEG chains appear to destabilize the bilayers, which facilitates the fusion and transport of the small vesicles to the larger ones. Potential applications of these well-structured and reproducibly produced multicompartment systems include drug delivery, where researchers could load a cocktail of drugs within the encapsulated vesicles, a process that could enhance the bioavailability of these substances. In addition, the production of artificial cells with multiple compartments provides a platform where researchers could carry out individual reactions in small, isolated spaces. Such a reactive space can avoid problems that occur when the environment can be destructive to reactants or products or when a diverse set of compounds difficult to obtain in a conventional reactor space are produced. Our work on these artificial cells with multicompartment structures also led us to formulate a hypothesis on the processes that possibly generated eukaryotic cells. We hope both that our research efforts will excite interest in these nanoparticles and that this research could lead to systems designed for specific scientific and technological applications and further insights into the evolution of eukaryotic cells. PMID:24735049

Paleos, Constantinos M; Pantos, A

2014-05-20

296

Very low level radioactive material  

International Nuclear Information System (INIS)

Man's environment contains naturally occurring radionuclides and doses from exposures to these radionuclides mostly cannot be avoided. Consequently, almost everything may be considered as very low level radioactive material. In practical terms, management and the selection of different routes for low level material is confined to material which was subject to industrial processing or which is under a system of radiological control. Natural radionuclides with concentrations reaching reporting or notification levels will be discussed below; nevertheless, the main body of this paper will be devoted to material, mainly of artificial origin, which is in the system involving notification, registration and licensing of practices and sources. It includes material managed in the nuclear sector and sources containing artificially produced radionuclides used in hospitals, and in industry. Radioactive materials emit ionising radiations which are harmful to man and his environment. National and international regulations provide the frame for the system of radiation protection. Nevertheless, concentrations, quantities or types of radionuclide may be such, that the material presents a very low hazard, and may therefore be removed from regulatory control, as it would be a waste of time and effort to continue supervision. These materials are said to be exempted from regulatory control. Material exempted in a particular country is no longer distinguishable from ''ordinary'' material and may be moved from country to country. Unfortunately, criteria for exempting radioactive materials differ strongly between countries and free trade. Therefore there is a necessity for an international approach to be developed for exemption levels

1993-01-01

297

Radioactivity and treatment of radioactive wastes  

International Nuclear Information System (INIS)

In this chapter (10) of the text-book treatment of radioactive wastes is described. This chapter consist of following sections: (1) Radioactivity; (2) Effect of ionizing radiation on organism; (3) Nuclear fuel cycle; (4) Nuclear energetics - present state and perspectives of development (in this section types of nuclear reactors are reviewed); (5) Radioactive wastes, treatment of radioactive wastes; (6) Review of legislative of the Slovak Republic about treatment of radioactive wastes and health protection at work with radioactive materials

2008-09-01

298

Sealed Radioactive Sources  

Science.gov (United States)

... in which the metal can become contaminated with radioactivity, EPA determined that lost, abandoned, or stolen radioactive ... and Health Administration (OSHA) OSHA regulates exposure to radioactivity in the workplace. Radioactive Source Recovery Efforts This ...

299

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.

300

Disposal of radioactive wastes  

International Nuclear Information System (INIS)

This book provides information on the origin, characteristics and methods of processing of radioactive wastes, as well as the philosophy and practice of their storage and disposal. Chapters are devoted to the following topics: radioactive wastes, characteristics of radioactive wastes, processing liquid and solid radioactive wastes, processing wastes from spent fuel reprocessing, processing gaseous radioactive wastes, fixation of radioactive concentrates, solidification of high-level radioactive wastes, use of radioactive wastes as raw material, radioactive waste disposal, transport of radioactive wastes and economic problems of radioactive wastes disposal. (C.F.)

1982-01-01

 
 
 
 
301

Radioactivity and foods  

Energy Technology Data Exchange (ETDEWEB)

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

Olszyna-Marzys, A.E. (Unified Lab. of Food and Drug Control, Guatemala City (Guatemala))

1991-01-01

302

Radioactivity; Die Radioaktivitaet  

Energy Technology Data Exchange (ETDEWEB)

The following topics are dealt with: The radioactive substances, the ionization of gases, measuring methods, the physical nature of radiations, radiation effects, the continuous production of radioactive matter, radioactive emanations, excited radioactivity, theory of transmutation series, the transmutation products of uranium, thorium, and actinium, the transmutation products of radium, the energy development, radioactive processes, atmospheric activity, the radioactivity as general property of matter. (HSI)

Rutherford, E.

2007-07-01

303

Radioactive waste  

International Nuclear Information System (INIS)

Focusing on radioactive waste management and disposal policies in the United Kingdom, Sweden and the Federal Republic of Germany, this book gives a detailed historical account of the policy process in these three countries, and draws out the implications for theory and public policy. This comparative approach underlines how profoundly different the policy process has been in different countries. By comparing the evolution of policy in three countries, fundamental questions about the formation and resolution of technical decisions under uncertainty are clarified. The analysis of nuclear strategy, the politics of nuclear power, and the shifting emphasis of government regulation redefines the issue of radwaste management and sets it at the heat of the current debate about power, the environment and society. The combination of up-to-date technological assessment with an account of the social and political implications of radwaste management makes'Radioactive Waste'particularly useful to students of environmental studies, geography and public administration. (author)

1991-01-01

304

[Simple artificial mouth model].  

Science.gov (United States)

A simple artificial mouth model is established under our laboratory condition. Development of monobacterial plaque and mixed bacterial plaque was studied in this artificial mouth model. The samples were subjected to viable count, microhardness measurement, etc. The result showed that the controlled conditions of the model can be used to study plaque development and earlier enamel lesion production on a time-dependent basis. It is concluded that the simple artificial mouth model is suitable for a wide range of dental applications. PMID:9387546

Zhu, M; Liu, Z; Li, M

1996-03-01

305

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

1987-01-01

306

Mechanism of glucan-induced agglutination in Streptococcus mutans. I. Binding of radioactive glucan to whole cells of S. mutans OMZ-176.  

Science.gov (United States)

The binding of radioactive glucan to Streptococcus mutans cells, which are agglutinated by dextrans, was examined. The glucan was synthesized from sucrose by extracellular glucosyltransferases from S. mutans FA-1 and was highly branched at C-3 and C-6 of D-glucose residues, containing 17% of a (1 leads to 3)inter-chain residues. Binding of glucan to whole cells of S. mutans OMZ-176, which were agglutinated by addition of glucan or Dextran T2000, was irreversible and followed saturation type kinetics; saturation was achieved at approximately 110 ng of glucan per ml. About 14 ng of glucan were bound per mg of the cells at the saturated concentration. The heated cells of this organism, however, had a relatively low ability of glucan-binding, compared with the freshly prepared and lyophilized cells. Binding to the heated cells was entirely of a non-saturation type. Binding of Dextran T2000 or T10 was determined by competition between the labeled glucan and unlabeled Dextrans for the binding site(s). Both Dextrans and glucan from S. mutans FA-1 were bound to the same site(s). Other organisms, which did not undergo glucan- and Dextran-induced agglutination, had a relatively lower ability of glucan-binding than S. mutans, which was agglutinated. PMID:36546

Suginaka, H; Ebisu, S; Kotani, S

1978-01-01

307

Environmental radioactivity annual report 1993  

International Nuclear Information System (INIS)

During 1993 artificial radioactivity in the environment in New Zealand and Rarotonga continued to be at trace level only, typical of recent years. There has been no significant change in artificial radioactivity status of the environment since 1992. Atmospheric and deposited radioactivity was monitored at Kaitaia, Hokitika and Rarotonga and milk radioactivity was monitored in Auckland, Taranaki and Westland. Average levels measured were: total beta activity in air, 0.15 mBq/m3; 90Sr deposition, 0.1 Bq/km2; 137Cs in milk, 0.15 Bq/g K; 90Sr in milk, 0.02 Bq/g Ca. Total beta activity depositions at Hokitika and Rarotonga were 172 Bq/m2 and 334 Bq/m2 respectively. Annual total 210Pb depositions at Kaitaia, Hokitika and Rarotonga were 48, 115, 33 Bq/m2 respectively. No artificial radionuclides were detected by gamma spectroscopic analysis of high-volume air filters during 1993, with weekly sampling periods. Annual average atmospheric 137Cs concentrations, assessed by analysis of yearly air filter aggregates, at Kaitaia, Hokitika and Rarotonga were 0.02, 0.05 and 3 respectively. Average atmospheric concentrations of natural 7Be and 210Pb were 2.9 mBq/m3 and 0.05 mBq/m3 respectively. Atmospheric beta activity was found to be made up of contributions from cosmogenic radionuclides (60%), 210Pb/210Bi (25%) and natural radionuclides in suspended dust (15%). A study of trends in atmospheric 137Cs concentrations, derived from analyses of yearly aggregates of air filters for the period 1986-1993, indicated that fission products from the Chernobyl reactor did not reach detectable levels in New Zealand, confirming earlier projections and indications. Fallout 210Pb and 210Po in diet contribute estimated annual average effective annual average effective dose commitments of 4.5 and 2.3 ?Sv respectively, compared to the total dose commitment of 90Sr and 137Cs, of about 2 ?Sv/y. The report includes data on trends in atmospheric radioactivity levels since 1987. (author). 15 refs., 7 tabs., 4 figs

1994-01-01

308

Optimization of beam and target combinations for hybrid reactor systems and for the fission-induced production of radioactive beams  

International Nuclear Information System (INIS)

This thesis work consists of two parts: a) theoretical, and b) experimental. We combine and use the high energy transport code LAHET, the low energy transport code MCNP, and the activation code CINDER. Our benchmarking calculations show that LAHET neglects the Coulomb dissociation for deuterons. By adding this missing term, we obtain a good agreement with the available data. We also conclude that LAHET describes well the data for isotope production yields if the ORNL fission model is employed for nuclei with Z>90. The 'default' RAL fission model gives too broad isotopic distributions and fails to reproduce the data in absolute value. We examine different combinations of beams, beam energies, spallation target and multiplying medium materials in order to optimize the neutron production, energy amplification and isotope production via neutron induced fissions. We show that the (d,xn) reactions could bring a number of important advantages when compared to the (p,xn) reactions. We conclude that the use of deuterons instead of protons should result in higher primary beam intensities, lower costs of the system and facilitate radioprotection problems. Within the SPIRAL Phase-II project at GANIL, we propose d(100 MeV)+Be?xn+U as an optimum combination for the production of neutron rich nuclei in the mass region 75?A?160. However, the production of tritium gas in the target-converter should be considered carefully. The use of heavier metal targets-converters may cause more severe problems of radioprotection.Our experimental work is closely related to the theoretical investigations. We measure the complete proton spectra for 1.00 and 200 MeV deuteron induced reactions on 8 thin targets (Be, C, Al, Ni, Nb, Ta,, Pb and U) and in the angular region 8 deg C ? ?p ? 120 deg C. The experiments were carried at LNS (Saclay, France) and at NAC (Faure, South Africa). Good quality data (within 10% in absolute value and with 4-8 MeV energy threshold) support our improved LAHET physics modelling for (d,xp) and, consequently, for (d,xn) reactions. (author)

1999-01-01

309

Introduction to artificial intelligence  

Energy Technology Data Exchange (ETDEWEB)

This book is an introduction on artificial intelligence. Topics include reasoning under uncertainty, robot plans, language understanding, and learning. The history of the field as well as intellectual ties to related disciplines are presented.

Charniak, E.; McDermott, D.

1985-01-01

310

Artificial Hydration and Nutrition  

Science.gov (United States)

... the fluid under the skin. This is called hypodermoclysis, or subcutaneous fluid replacement. Another method of artificial ... a family member or another caregiver can do hypodermoclysis at home after a doctor or nurse shows ...

311

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)

2012-03-01

312

Introduction to artificial intelligence  

Energy Technology Data Exchange (ETDEWEB)

The author discusses the development of artificial intelligence (AI). He explains the basic elements of AI: Heuristic search, knowledge representation, AI languages and tools, Natural Language Processing, computer vision, expert systems and problem solving and planning.

Gevarter, W.B.

1987-09-01

313

Study of proton-induced reactions in a radioactive 129I target at Ep=660 MeV  

International Nuclear Information System (INIS)

Two NaI (85% 129I and 15% 127I) targets were exposed to a beam of 660-MeV protons. Cross sections for formation of 76 residual nuclei were obtained by the induced activity method. The results are compared with other experimental data on 127I and theoretical calculations by eleven models contained in the codes LAHET3 (using the Bertini+Dresner, ISABEL+Dresner, INCL+Dresner, and INCL+ABLA options), CASCADE, CEM95, CEM2K, LAQGSM+GEM2, CEM2k+GEM2, LAQGSM+GEMINI, and CEM2k+GEMINI. Most of the models describe spallation products with masses close to the target reasonably well while the reliability of the codes differs greatly in the deep spallation and fission/fragmentation regions. The difficulties in describing products with A=40-80 by all of the codes tested here except for CEM2k+GEMINI and LAQGSM+GEMINI is related to the neglect of fission (and fragmentation) processes for targets as light as 129I. (orig.)

2003-09-01

314

Study of Proton Induced Reactions in a Radioactive 129-I Target at Ep=660 MeV  

CERN Document Server

Two NaI (85% 129-I and 15% 127-I) targets were exposed to a beam of 660-MeV protons. Cross sections for formation of 76 residual nuclei were obtained by the induced activity method. The results are compared with other experimental data on 127-I and theoretical calculations by eleven models contained in the codes LAHET3 (using the Bertini+Dresner, ISABEL+Dresner, INCL+Dresner, and INCL+ABLA options), CASCADE, CEM95, CEM2K, LAQGSM+GEM2, CEM2k+GEM2, LAQGSM+GEMINI, and CEM2k+GEMINI. Most of the models describe spallation products with masses close to the target reasonably well while the reliability of the codes differs greatly in the deep spallation and fission/fragmentation regions. The difficulties in describing products with A=40-80 by all of the codes tested here except for CEM2k+GEMINI and LAQGSM+GEMINI is related to the neglect of fission (and fragmentation) processes for targets as light as 129-I.

Pronskikh, V S; Balabekyan, A R; Barashenkov, V S; Dzhelepov, V P; Gustov, S A; Filinova, V P; Kalinnikov, V G; Krivopustov, M I; Mirokhin, I V; Solnyshkin, A A; Stegailov, V I; Tsoupko-Sitnikov, V M; Mrazek, J; Brandt, R; Westmeier, W; Odoj, R; Mashnik, S G; Sierk, A J; Prael, R E; Gudima, K K; Baznat, M I

2004-01-01

315

Artificial black holes  

Digital Repository Infrastructure Vision for European Research (DRIVER)

We study black holes for the linear hyperbolic equations describing the wave propagation in the moving medium. Such black holes are called artificial since the Lorentz metric associated with the hyperbolic equation does not necessary satisfies the Einstein equations. Artificial black holes also arise when we consider perturbations of the Einstein equations. In this paper we review author's results of [E2] and [E3] on the existence and the stability of black holes for the sta...

Eskin, Gregory

2011-01-01

316

Managing artificial lift  

Energy Technology Data Exchange (ETDEWEB)

The goal of this work is to describe an approach to produce a well for maximum profitability by managing artificial lift effectively. Achieving maximum profitability from an artificially lifted well begins with selecting the lift method and continues with selecting materials, protecting materials, monitoring production data, and monitoring equipment performance. Changes suggested by the monitoring process strive to increase the profitability on an individual well basis.

Bucaram, S.M.; Patterson, J.C. (Arco E P Technology, Plano, TX (United States))

1994-04-01

317

Intelligence: Real or artificial?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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 original...

Schlinger, Henry D.

1992-01-01

318

Soils: man-caused radioactivity and radiation forecast  

International Nuclear Information System (INIS)

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

2007-09-02

319

Artificial skin. Jinko hifu  

Energy Technology Data Exchange (ETDEWEB)

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.

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

1993-06-15

320

Mathematical problems in modeling artificial heart  

Digital Repository Infrastructure Vision for European Research (DRIVER)

In this paper we discuss some problems arising in mathematical modeling of artificial hearts. The hydrodynamics of blood flow in an artificial heart chamber is governed by the Navier-Stokes equation, coupled with an equation of hyperbolic type subject to moving boundary conditions. The flow is induced by the motion of a diaphragm (membrane) inside the heart chamber attached to a part of the boundary and driven by a compressor (pusher plate). On one side of the diaphragm is the blood and o...

1995-01-01

 
 
 
 
321

Radioactive dating  

International Nuclear Information System (INIS)

The history of radioactive dating methods and their impact on such scientific fields as archaeology, geology, hydrology, climatology, and environmental protection are described. Significant advances in understanding have resulted from their application, and current and future developments promise exciting advances in the areas of application and the available age ranges. New techniques, capable of determining the ages of extremely small (milligram) samples, are described allowing reliable dates to be determined for, amongst other things, art or religious treasures, previously forbidden because of the size of sample required. Enrichment techniques, e.g. using lasers, allow extension of the range of radiocarbon dating, and equipment developments allow more accurate measurements to be made. (author)

1983-01-01

322

Research on radioactivity in marine off Rokkasho village of Aomori prefecture  

Energy Technology Data Exchange (ETDEWEB)

The seawater samples were collected at the fixed points off the Rokkasho village of Aomori prefecture. The concentration level of radioactive substance was researched for these samples. The radioactivity of {sup 239,240}Pu, {sup 90}Sr, {sup 137}Cs and so on was detected as artificial radionuclides. Difference in radioactivity was not observed for the seawater samples in each measurement point. These radioactivities were made uniform distribution. Compared with the recent data by other research institutions observed in the off Rokkasho village, data of comparable radioactivity were obtained. This report describes the measurement results of radioactive concentration undertaken in the 1996 and 1997 fiscal year. (author)

Yamamoto, Tadatoshi [Japan Atomic Energy Research Inst., Mutsu, Aomori (Japan). Mutsu Establishment; Gunji, Katsufumi; Igarashi, Nobuyuki

1998-12-01

323

Radioactive wastes  

International Nuclear Information System (INIS)

A review is presented on the environmental behavior of radioactive wastes. The management of high-level wastes and waste disposal methods were discussed. Some topics included were ore processing, coagulation, absorption and ion exchange, fixation, ground disposal, flotation, evaporation, transmutation and extraterrestrial disposal. Reports were given of the 226Ra, 224Ra and tritium activity in hot springs, 90Sr concentrations in the groundwater and in White Oak Creek, radionuclide content of algae, grasses and plankton, radionuclides in the Danube River, Hudson River, Pacific Ocean, Atlantic Ocean, Lake Michigan, Columbia River and other surface waters. Analysis showed that 239Pu was scavenged from Lake Michigan water by phytoplankton and algae by a concentration factor of up to 10,000. Benthic invertebrates and fish showed higher 239Pu concentrations than did their pelagic counterparts. Concentration factors are also given for 234Th, 60Co, Fe and Mr in marine organisms. Two models for predicting the impact of radioactivity in the food chain on man were mentioned. In an accidental release from a light-water power reactor to the ocean, the most important radionuclides discharged were found to be 90Sr, 137Cs, 239Pu and activation products 65Zr, 59Fe, and 95Zr

1975-01-01

324

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)

1987-01-01

325

Light-driven artificial molecular machines  

Science.gov (United States)

Artificial molecular machines represent a growing field of nanoscience and nanotechnology. Stimulated by chemical reagents, electricity, or light, artificial molecular machines exhibit precisely controlled motion at the molecular level; with this ability molecular machines have the potential to make significant impacts in numerous engineering applications. Compared with molecular machines powered by chemical or electrical energy, light-driven molecular machines have several advantages: light can be switched much faster, work without producing chemical waste, and be used for dual purposes-inducing (writing) as well as detecting (reading) molecular motions. The following issues are significant for light-driven artificial molecular machines in the following aspects: their chemical structures, motion mechanisms, assembly and characterization on solid-state surfaces. Applications in different fields of nanotechnology such as molecular electronics, nano-electro-mechanical systems (NEMS), nanophotonics, and nanomedicine are envisaged.

Zheng, Yue Bing; Hao, Qingzhen; Yang, Ying-Wei; Kiraly, Brian; Chiang, I.-Kao; Huang, Tony Jun

2010-08-01

326

Ambient radioactivity levels and radiation doses. Annual report 2011; Umweltradioaktivitaet und Strahlenbelastung. Jahresbericht 2011  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2013-07-15

327

Ambient radioactivity levels and radiation doses. Annual report 2010; Umweltradioaktivitaet und Strahlenbelastung. Jahresbericht 2010  

Energy Technology Data Exchange (ETDEWEB)

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.

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

2012-04-15

328

Uranium and radioactivity  

International Nuclear Information System (INIS)

The article gives results of investigations on uranium content and the proportion of induced and natural radioactivity in wines of different vines and regions. The ecological chain of ground, vine, grape, grape-juice, and wine is described, and the author shows that 14C and T measurements can be used to determine the age of wines with the aim of detecting adulterated vintages and blends of different years. The 14C and T content also indicates a direct connection with nuclear explosions. (RB/AK)

1974-01-01

329

Artificial Heart Design Challenge  

Science.gov (United States)

Students are presented with a hypothetical scenario in which they are biomedical engineers asked to design artificial hearts. Using the engineering design process as a guide, the challenge is established and students brainstorm to list everything they might need to know about the heart in order to create a complete mechanical replacement (size, how it functions, path of blood etc.). They conduct research to learn the information and organize it through various activities. They research artificial heart models that have already been used and rate their performance in clinical trials. Finally, they analyze the data to identify the artificial heart features and properties they think work best and document their findings in essay form.

Bio-Inspired Technology and Systems (BITS) RET,

330

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)

1987-01-01

331

Artificial black holes  

CERN Document Server

We study black holes for the linear hyperbolic equations describing the wave propagation in the moving medium. Such black holes are called artificial since the Lorentz metric associated with the hyperbolic equation does not necessary satisfies the Einstein equations. Artificial black holes also arise when we consider perturbations of the Einstein equations. In this paper we review author's results of [E2] and [E3] on the existence and the stability of black holes for the stationary wave equations in two space dimensions, and in the axisymmetric case.

Eskin, Gregory

2011-01-01

332

Model of radioactive background of solid environmental subjects  

Energy Technology Data Exchange (ETDEWEB)

Environmental subjects are complicated technologically influenced systems with multi-levelled spatial and temporary inhomogeneity of radionuclides distribution. Their radioactive background is a sum of a number of natural and techno-genic factors: natural radioactivity, nuclear weapon testing, using nuclear technologies in industries, etc. Correct determination of radioactive background is in fact a basis for accepting just juridic, economic and social decisions. A general procedure of computation of upper borders of radioactive background of environmental subjects is offered. It is proved to work in application to soil as a triple system consisting of sand, clay and organic matter. There is a reason to believe that it works as well for all environmental subjects with components of significantly different radioactivity. The procedure is modelling of confident interval of background radioactivity which is based upon the different ability of various components of environmental subject to accumulate natural and artificial radionuclides. (author)

Gablin, V.; Verbova, L.; Sobolev, A. [Moscow Scientific-Industrial Association Radon 2/14, Moscow (Russian Federation)

2004-07-01

333

Radioactive Waste Management  

International Nuclear Information System (INIS)

Description of radioactive waste and principles of their management in Lithuania is presented. Information on the requirements of management of radioactive waste is provided. Legislation regulating management of radioactive waste is listed

2002-01-01

334

An Assessment of Radioactivity of Selected Industrial Waste  

International Nuclear Information System (INIS)

phosphogypsum (phph) is a by-product in the manufacture of phosphoric acid for the artificial fertilizer industry. In the present work, qualitative and quantitative radioactive analysis are carried for phph of National Company of Abuzabal for chemical fertilizers. Gamma ray spectroscopy techniques are applied. The present study reveals that the radioactivity resulted from these wastes is out of the international standards, and it is strongly not recommended to be used as a construction material or for dwellings

1998-12-12

335

Radioactivity for man's benefit  

International Nuclear Information System (INIS)

Nuclear medicine is the application of radionuclides in the diagnosis and treatment of disease. The workhorse of nuclear medicine is the artificially produced radionuclide technetium-99m (Tc-99m). Tc-99m is employed as a radioactive label for many different compounds used to study various organs. Using these compounds it has become possible to image organ structure, organ function and the disturbance of organ function. The utilization of radionuclides in medical research in the Republic of South Africa has been actively supported since 1959 by mainly three organizations, namely the South African Medical Research Council, the Council for Scientific and Industrial Research and the Atomic Energy Corporation of South Africa. This support, together with the consistency of the production of valuable radionuclides, has made it possible for those centres which have nuclear medicine facilities to conduct research of international standing. This research includes studies on cancer, liver and kidney transplants, the heart, diabetes and blood platelet kinetics. The National Accelerator Centre at Faure in the Cape is now poised to produce radionuclides hetherto unavailable in the Republic of South Africa. This will enable exciting new techniques such as Positron emission tomography to become a reality. 1 fig

1988-01-01

336

Natural and artificial radioactivity in soils of forests  

International Nuclear Information System (INIS)

Levels of "2"2"2 Rn, "4"0 K, "2"3"5 U, "2"2"6 Ra and "1"3"7 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 "4"0 K, "2"3"5 U, "2"2"6 Ra and "1"3"7 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 "4"0 K, "2"3"5 U, "2"2"6 Ra and "1"3"7 Cs are discussed as function of the perturbation grade of the soil and atmospheric pollution. (Author)

2001-12-05

337

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)

1990-01-01

338

Nuclear physics with radioactive beams  

International Nuclear Information System (INIS)

Radioactive beams can be produced through two different and complementary ways:i. the production at rest of radioactive nuclei, followed by their acceleration using conventional techniques.This method is the best for producing low energy radioactive beams. ii. the fragmentation of high energy heavy ion beams ( over 30 MeV/u), followed by the selection and purification of a given secondary beam using magnetic spectrometers. This technique leads to high energy radioactive beams. Both methods have now been used in several laboratories in the world. Examples of the corresponding experimental equipment will be presented, and especially Lise 3, Sissi, and the spiral project at GANIL. Radioactive beams have used for several purposes in nuclear physics: i. they constitute the fastest technique ever used for transferring exotic nuclei from the production point to a well shielded place where detectors can be operated for studying their properties in good conditions. At the same time, they can be identified using solid state detectors and the time-of-flight/energy-loss technique. Illustrations of the results obtained in this domain (mass and half-life measurements, recent identification of the isotope sup 1 sup 0 sup 0 Sn) is given. ii. they are used to induce nuclear reactions which may bring new information on nuclear structure. For example, the measurement of total reaction cross-sections for many radioactive projectiles revealed the existence of halo nuclei such as sup 1 sup 1 Li and sup 1 sup 1 Be. Beams of these isotopes have been extensively used to precise their structure.iii. in the domain of nuclear astrophysics, radioactive beams are used to measure, through direct or indirect methods, the cross sections for reactions of crucial interest in nucleosynthesis. Finally, radioactive beams of light positron emitters, such as sup 1 sup 9 Ne have considerable interest for medical purposes and especially in the growing field of heavy-ion radiotherapy. 8 figs., 24 refs. (author)

1994-07-18

339

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.)

1976-01-01

340

Artificial intelligence and automation  

CERN Document Server

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

Bourbakis, NG

1998-01-01

 
 
 
 
341

Artificial intelligence within AFSC  

Science.gov (United States)

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

Gersh, Mark A.

1990-01-01

342

Artificial recharge of groundwater  

Science.gov (United States)

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

343

Artificial intelligence and robotics  

Energy Technology Data Exchange (ETDEWEB)

This report examines the state-of-the-art in artificial intelligence and robotics technologies and their potential in terms of Army needs. Assessment includes battlefield technology, research and technology insertions, management considerations and recommendations related to research and development personnel, and recommendations regarding the Army's involvement in the automated plant.

Peden, I.C.; Braddock, J.V.; Brown, W.; Langendorf, R.M.

1982-09-01

344

Artificial binary data scenarios  

Digital Repository Infrastructure Vision for European Research (DRIVER)

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

Dolnicar, Sara; Leisch, Friedrich; Weingessel, Andreas

1998-01-01

345

BASIC artificial intelligence  

Energy Technology Data Exchange (ETDEWEB)

Although artificial intelligence is usually associated with special computer languages, this introductory book will give a firm foundation to this fascinating subject to users who are familiar with BASIC. Topics considered include introduction to BASIC, varieties of logic and reasoning, strategy and analysis, relationships and the role of memory, natural language, and learning from experience.

James, M.

1986-01-01

346

Applications of artificial intelligence  

Energy Technology Data Exchange (ETDEWEB)

This book presents papers given at a conference on expert systems and artificial intelligence. Topics considered at the conference included the location of multiple faults by diagnostic expert systems, knowledge-based systems, natural language, image processing, computer vision, and identification systems.

Gilmore, J.F.

1984-01-01

347

Artificial intelligence. Second edition  

Energy Technology Data Exchange (ETDEWEB)

This book introduces the basic concepts of the field of artificial intelligence. It contains material covering the latest advances in control, representation, language, vision, and problem solving. Problem solving in design and analysis systems is addressed. Mitcell's version-space learning procedure, Morevec's reduced-images stereo procedure, and the Strips problem solver are covered.

Winston, P.H.

1984-01-01

348

Argumentation in Artificial Intelligence  

CERN Document Server

Examines the intersection between two fields of inquiry, including Argumentation Theory and Artificial Intelligence. This book presents an overview of key concepts in argumentation theory and of formal models of argumentation in AI. It offers a review of the foundational issues in argumentation and formal argument modeling.

Simari, Guillermo

2009-01-01

349

Airside Applications for Artificial Turf.  

Science.gov (United States)

A study to investigate the considerations and concerns associated with airside applications of artificial turf was conducted using input from the artificial turf manufacturers and by administering and discussing questionnaire surveys via site visits to ai...

T. Connelly C. Teubert

2006-01-01

350

Radiation protection. Radioactivity and health. 3. ed.  

International Nuclear Information System (INIS)

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

1986-01-01

351

Application of biotechnology to the problem of the disposal of radioactive wastes  

Energy Technology Data Exchange (ETDEWEB)

Artificial biological systems are proposed for use in the treatment of low- and intermediate-level radioactive wastes. The microbial conversion of organic and inorganic substances under continuous conditions, involving the turnover of matter, will allow a significant reduction in volume of radioactive wastes. Such specialised systems can act as a biogeochemical barrier for radionuclide transport. 14 refs.

Belyi, A.V.; Gurevich, Yu.L.; Pustoshilov, P.P.; Sadovsky, M.G. [Laboratory of the Ecological Biotechnology, Institute of Biophysics of Siberian Division of Russian Academy of Sciences, Krasnoyarsk (Russian Federation)

1998-07-01

352

Radio-ecological aspects in artificial groundwater recharge  

International Nuclear Information System (INIS)

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

1979-05-18

353

Survey monitoring of environmental radioactivity in Daejeon area  

Energy Technology Data Exchange (ETDEWEB)

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

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

2000-12-15

354

Survey monitoring of environmental radioactivity in Daejeon area  

International Nuclear Information System (INIS)

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

2000-01-01

355

Survey monitoring of environmental radioactivity in Daejeon area  

International Nuclear Information System (INIS)

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

2001-01-01

356

Survey monitoring of environmental radioactivity in Daejeon area  

International Nuclear Information System (INIS)

Systematic understanding of the distribution of environmental radioactivity and radiation level in Daejeon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Daejeon Radiation Monitoring Station in 2002. In conclusion, the natural environmental radiation level in Daejeon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period

2002-01-01

357

Survey monitoring of environmental radioactivity in Daejeon area  

International Nuclear Information System (INIS)

Systematic understanding of the distribution of environmental radioactivity and radiation level in Daejeon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Daejeon Radiation Monitoring Station in 2002. In conclusion, the natural environmental radiation level in Daejeon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period

2003-01-01

358

Survey monitoring of environmental radioactivity in Daejeon area  

Energy Technology Data Exchange (ETDEWEB)

Systematic understanding of the distribution of environmental radioactivity and radiation level in Daejeon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Daejeon Radiation Monitoring Station in 2002. In conclusion, the natural environmental radiation level in Daejeon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period.

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

2003-12-15

359

Survey monitoring of environmental radioactivity in Daejeon area  

Energy Technology Data Exchange (ETDEWEB)

Systematic understanding of the distribution of environmental radioactivity and radiation level in Daejeon, including Chungchung area, in normal circumstance, and rapid detection of unusual variation of the radiation level in emergency situation thereby ensure public safety are the objectives of this project to be carried out. This report summarizes and interprets environmental radiation/radioactivity monitoring data obtained at Daejeon Radiation Monitoring Station in 2002. In conclusion, the natural environmental radiation level in Daejeon area has been preserved as usual and no significant artificial enhancement in environmental radioactivity was observed during the course of this survey and monitoring period.

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

2002-12-15

360

Survey monitoring of environmental radioactivity in Daejeon area  

Energy Technology Data Exchange (ETDEWEB)

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

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

2001-12-15

 
 
 
 
361

Artificially structured magnetic materials  

Energy Technology Data Exchange (ETDEWEB)

This document reports the progress made during the first six months of the current three-year DOE grant on Artificially Structured Magnetic Materials.'' However, because some of the results of our previous three-year DOE grant on Artificially Structured Superconductors'' continue to emerge, both topics are addressed in this Progress Report. This report describes progress with DOE funding during the current calendar year; description of the research to be conducted during the remaining six months of the current grant year; a description of the status of the graduate students working on this research; lists of the invited talks, seminars and colloquia, of other recognition of our research, and of the publications crediting DOE sponsorship; and a summary of current and pending federal support. Since the research proposed to be conducted during the next 2 1/2 years is described in detail in our DOE proposal, it is only briefly reviewed here.

Falco, C.M.

1990-09-28

362

Spatially Resolved Artificial Chemistry  

DEFF Research Database (Denmark)

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

Fellermann, Harold

2009-01-01

363

Report on artificial intelligence  

Energy Technology Data Exchange (ETDEWEB)

The general perception of artificial intelligence is changing, under the combined impetus of work being carried out in Japan and in the United States. In Europe, Britain has adopted an ambitious national programme on this subject and the European community has launched some new initiatives on artificial intelligence, within the framework of the Esprit Programme. This report is intended to express the views of those who feel it is urgent and necessary for France to define an overall policy on this subject, which is considered by many to be crucial for the development of computer science, both in its fundamental techniques and its applications. Researchers, teachers and industrialists came together to advance proposals along these lines, thus providing a complementary drive to the campaign launched in 1982 when they issued their vigorous appeal for computer equipment. This report insists on prompt action: there is no further time to be lost.

Barthes, M.; Borillo, M.; Cochet, M.; Colmerauer, A.; Cousineau, M.; Farreny, H.; Faugeras, O.; Gallaire, H.; Girard, E.; Greussay, P.; Gross, M.; Guiho, G.; Haton, J.P.; Huet, G.; Jouannaud, J.P.; Kodratoff, Y.; Masson, M.; Naffah, N.; Nivat, M.; Recoque, A.; Roucairol, G.; Stephan, P.; Trilling, L.

1983-01-01

364

Whither Artificial Reproduction?  

Digital Repository Infrastructure Vision for European Research (DRIVER)

Artificial reproduction now offers sub fertile couples a number of options which raise scientific and ethical questions. This article discusses the Canadian and British experiences in formulating regulations and legislation in this important field. Current work on mammalian embryo research foretells the direction which human research will take. This article stresses the need for family physicians' participation in the ethical decisions that accompany these new developments.

Percival-smith, Robin

1985-01-01

365

Introducing artificial intelligence  

Energy Technology Data Exchange (ETDEWEB)

This book is an introduction to the field of artificial intelligence. The volume sets Al in a broad context of historical attitudes, imaginative insights, and ideas about intelligence in general. The author offers a wide-ranging survey of Al concerns, including cognition, knowledge engineering, problem inference, speech understanding, and perception. He also discusses expert systems, LISP, smart robots, and other Al products, and provides a listing of all major Al systems.

Simons, G.L.

1985-01-01

366

Artificial dewatering methods  

Energy Technology Data Exchange (ETDEWEB)

Elutriation of peat into hydropeat and conveying it through pipework to an artificial dewatering system at a drying plant offers a year round peat production alternative. This article presents testing equipment and tests performed at the Domestic Fuel Lab. of Technical Research Centre of Finland. The test equipment consists of a defibrator/grading cylinder, compartments for treating and mixing of chemicals and a continuous action filter band press.

Niittylae, H.; Lehtinen, U.; Pirkonen, P.

1983-01-01

367

Artificial sweetener; Jinko kanmiryo  

Energy Technology Data Exchange (ETDEWEB)

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

NONE

1999-08-01

368

Antithrombotic artificial organs  

International Nuclear Information System (INIS)

A new antithrombotic material useful for making artificial organs (artificial blood vessel, artificial heart, etc.) can be prepared by graft-polymerizing an acrylic ester (methyl methacrylate, methyl acrylate, ethyl acrylate, etc.) with a synthetic fiber (teflon, etc.). The graft-polymerization can be carried out by means of gamma radiation with cobalt 60 (dose rate 2.6x10"3 r/min., total dose 8x10"4 to 3.5x10"5 r). A graft ratio of 5 to 80% is attainable. In one example, a tubular sample made of teflon fiber having an inner diameter of 5 to 10 mm was immersed into methyl methacrylate in an ampoule in the absence of air and exposed to cobalt 60 gamma ray at the dose rate of 3.18x10"3 rad/min. After extraction with acetone, the sample was dried. The total dose was 3.5x10"5 rad and the graft ratio was ca. 25%. The sample was transplanted to vena cava of dog. No formation of thrombus was observed by autopsy (4 months after the transplantation). In control (teflon tube not graft-polymerized) thrombus was observed by autopsy 7 days after the transplantation. (Kaichi, S.)

1971-01-01

369

Thermal fluctuations in artificial spin ice.  

Science.gov (United States)

Artificial spin ice systems have been proposed as a playground for the study of monopole-like magnetic excitations, similar to those observed in pyrochlore spin ice materials. Currents of magnetic monopole excitations have been observed, demonstrating the possibility for the realization of magnetic-charge-based circuitry. Artificial spin ice systems that support thermal fluctuations can serve as an ideal setting for observing dynamical effects such as monopole propagation and as a potential medium for magnetricity investigations. Here, we report on the transition from a frozen to a dynamic state in artificial spin ice with a square lattice. Magnetic imaging is used to determine the magnetic state of the islands in thermal equilibrium. The temperature-induced onset of magnetic fluctuations and excitation populations are shown to depend on the lattice spacing and related interaction strength between islands. The excitations are described by Boltzmann distributions with their factors in the frozen state relating to the blocking temperatures of the array. Our results provide insight into the design of thermal artificial spin ice arrays where the magnetic charge density and response to external fields can be studied in thermal equilibrium. PMID:24908258

Kapaklis, Vassilios; Arnalds, Unnar B; Farhan, Alan; Chopdekar, Rajesh V; Balan, Ana; Scholl, Andreas; Heyderman, Laura J; Hjörvarsson, Björgvin

2014-07-01

370

Six-year experiences in the environmental radioactivity monitoring in Taiwan  

International Nuclear Information System (INIS)

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

1980-03-14

371

Technical report from Radioactive Waste Management Funding and Research Center  

International Nuclear Information System (INIS)

As the only one Japanese organization specialized in radioactive waste, RWMC (Radioactive Waste Management Funding and Research Center) has been conducting the two major roles; R and D and the fund administration for radioactive waste management. The focus of its studies includes land disposal of LLW (Low-level radioactive wastes) and it has gradually extended to research on management and disposal techniques for high-level (HLW) and TRU wastes and studies on securing and managing the funds required for disposal of these wastes. The present document is the yearly progress report of 2006 and the main activities and research results are included on spent fuel disposal techniques including radon diffusion and emanation problem, performance studies on underground facilities for radioactive waste disposal and its management, technical assessment for geological environment, remote control techniques, artificial barrier systems proposed and its monitoring systems, and TRU disposals. (S. Ohno)

2007-01-01

372

Environmental radioactivity in New Zealand and Rarotonga : annual report 2006  

International Nuclear Information System (INIS)

Artificial radioactivity in the environment in New Zealand and Rarotonga monitored during 2006 continued to be at trace levels only, typical of recent years during which there has been no significant change in the radioactivity status of the environment. Atmospheric radioactivity was monitored at Kaitaia, Rarotonga and Chatham Islands; deposited radioactivity was monitored at Hokitika; and radioactivity in milk was monitored in the Waikato, Taranaki and Westland regions. The annual total beta concentration in deposition in Hokitika was 409 ± 29 Bq/m2. The annual average levels of caesium-137 (137Cs) in milk powder were: 137Cs in milk in Waikato = 0.75 ± 0.29 Bq/kg; 137Cs in milk in Taranaki = 0.98 ± 0.33 Bq/kg; 137Cs in milk in Westland = 0.47 ± 0.25 Bq/kg. (author). 6 refs., 2 tabs

373

Environmental radioactivity in New Zealand and Rarotonga : annual report 2005  

International Nuclear Information System (INIS)

Artificial radioactivity in the environment in New Zealand and Rarotonga monitored during 2005 continued to be at trace levels only, typical of recent years during which there has been no significant change in the radioactivity status of the environment. Atmospheric radioactivity was monitored at Kaitaia, Rarotonga and Chatham Islands; deposited radioactivity was monitored at Hokitika; and radioactivity in milk was monitored in the Waikato, Taranaki and Westland regions. The annual total beta concentration in deposition in Hokitika was 327 ± 21 Bq/m2. The annual average levels of 137Cs in milk powder were: 137Cs in milk in Waikato = 0.81 ± 0.29 Bq/kg; 137Cs in milk in Taranaki = 0.84 ± 0.32 Bq/kg; 137Cs in milk in Westland = 0.49 ± 0.24 Bq/kg. (author). 6 refs., 2 tabs

374

Radioactivity of wood ash  

International Nuclear Information System (INIS)

STUK (Finnish Radiation and Nuclear Safety Authority) has investigated natural and artificial radioactivity in wood ash and radiation exposure from radionuclides in ash since 1996. The aim was to consider both handling of ash and different ways of using ash. In all 87 ash samples were collected from 22 plants using entirely or partially wood for their energy production in 1996-1997. The sites studied represented mostly chemical forest industry, sawmills or district heat production. Most plants used fluidised bed combustion technique. Samples of both fly ash and bottom ash were studied. The activity concentrations of radionuclides in samples of, e.g., dried fly ash from fuel containing more than 80% wood were determined. The means ranged from 2000 to less than 50 Bq kg-1, in decreasing order: 137Cs, 40K, 90Sr, 210Pb,226Ra, 232Th, 134Cs, 235U. In bott radionuclide contents decreased in the same order as in fly ash, but were smaller, and 210Pb was hardly detectable. The NH4Ac extractable fractions of activities for isotopes of alkaline elements (K, Cs) in bottom ash were lower than in fly ash, whereas solubility of heavier isotopes was low. Safety requirements defined by STUK in ST-guide 12.2 for handling of peat ash were fulfilled at each of the sites. Use of ash for land-filling and construction of streets was minimal during the sampling period. Increasing this type of ash use had often needed further investigations, as description of the use of additional materials that attenuate radiation. Fertilisation of forests with wood ash adds slightly to the external irradiation in forests, but will mostly decrease doses received through use of timber, berries, mushrooms and game meat. (orig.)

2000-01-01

375

Radioactive tracers in the sea  

International Nuclear Information System (INIS)

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

1980-10-03

376

Radioactivity measurements as tool for physics dissemination  

International Nuclear Information System (INIS)

In general people associate environmental radioactivity with the artificial radioactivity and knows very little about natural radioactivity. Thus there is a critical need to improve nuclear physics public education. From 2005 in Italy two programs were promoted from Ministry of Education and University and National Institute of Nuclear Physics (INFN) for scientific dissemination in the field of environmental radioactivity. High school students in many Italian regions were involved in particular in indoor radon measurements. With this program students acquired awareness about the risks of inhalation of radon and its progeny and at the same time contributed to carry out radon monitoring, participating to all the experimental phases, from detectors set-up to data analysis. In particular we report about the activities carried out at Catania University and INFN division regarding a survey in the eastern Sicily. The overall monitoring, spanned over a period of 5 years, was carried out using passive nuclear track detection technique, through CR-39 dosimeters. In total about 500 detectors were placed in dwellings and schools in 57 locations. The investigated area have shown medium-high indoor radon concentrations, higher than the Italian average (70 Bq/m3). From the evaluation of the participating teachers and students, this kind of activities represents a successful strategy to enhance dissemination of physics, in particular in radioactivity topics. (author)

2014-01-01

377

Potentiated clinoptilolite: artificially enhanced aluminosilicate reduces symptoms associated with endoscopically negative gastroesophageal reflux disease and nonsteroidal anti-inflammatory drug induced gastritis  

Directory of Open Access Journals (Sweden)

Full Text Available Wilna Potgieter, Caroline Selma Samuels, Jacques Renè SnymanDepartment of Pharmacology, School of Medicine, Faculty of Health Sciences, University of Pretoria, Pretoria, Gauteng, South AfricaPurpose: The cation exchanger, a potentiated clinoptilolite (Absorbatox™ 2.4D, is a synthetically enhanced aluminosilicate. The aim of this study was to evaluate the possible benefits of a potentiated clinoptilolite as a gastroprotective agent in reducing the severity of clinical symptoms and signs associated with 1 endoscopically negative gastroesophageal reflux disease (ENGORD and 2 nonsteroidal anti-inflammatory drug (NSAID medication.Methods and patients: Two randomized, double-blind, placebo-controlled, pilot studies, the ENGORD and NSAID studies, were conducted. After initial negative gastroscopy, a total of 25 patients suffering from ENGORD were randomized to receive either placebo capsules or 750 mg Absorbatox twice daily for 14 days. The NSAID study recruited 23 healthy patients who received orally either 1,500 mg Absorbatox or placebo three times daily, plus 500 mg naproxen twice daily. Patients underwent gastroscopic evaluation of their stomach linings prior to and on day 14 of the study. Gastric biopsies were obtained and evaluated via the upgraded Sydney system, whereas visible gastric events and status of the gastric mucosa were evaluated via a 0–3 rating scale. During both studies, patients recorded gastric symptoms in a daily symptom diary.Results: In the ENGORD study, patients who received the potentiated clinoptilolite reported a significant reduction (P?0.05 in severity of symptoms including reduction in heartburn (44%, discomfort (54%, and pain (56%. Symptom-free days improved by 41% compared to the group who received placebo (not significant. This was over and above the benefits seen with the proton pump inhibitor. In the NSAID study, the reduction in gastric symptom severity was echoed in the group who received the potentiated clinoptilolite. Treatment with the potentiated clinoptilolite resulted in significant prevention (P?0.05 of mucosal erosion severity as graded by the gastroenterologist.Conclusion: Absorbatox is a nonabsorbable aluminosilicate with potential gastroprotective benefits as it protected against ENGORD symptoms and NSAID-induced gastric events. The exact mechanism of action is not clear but may be due to its binding to hydrogen ions and biologically active amines and nitrates.Keywords: cation exchanger, gastro-protective agent, endoscopy, zeolite

Potgieter W

2014-07-01

378

Artificial intelligence: Human effects  

Energy Technology Data Exchange (ETDEWEB)

This book presents an up-to-date study of the interaction between the fast-growing discipline of artificial intelligence and other human endeavors. The volume explores the scope and limitations of computing, and presents a history of the debate on the possibility of machines achieving intelligence. The authors offer a state-of-the-art survey of Al, concentrating on the ''mind'' (language understanding) and the ''body'' (robotics) of intelligent computing systems.

Yazdani, M.; Narayanan, A.

1984-01-01

379

Artificial mismatch hybridization  

Energy Technology Data Exchange (ETDEWEB)

An improved nucleic acid hybridization process is provided which employs a modified oligonucleotide and improves the ability to discriminate a control nucleic acid target from a variant nucleic acid target containing a sequence variation. The modified probe contains at least one artificial mismatch relative to the control nucleic acid target in addition to any mismatch(es) arising from the sequence variation. The invention has direct and advantageous application to numerous existing hybridization methods, including, applications that employ, for example, the Polymerase Chain Reaction, allele-specific nucleic acid sequencing methods, and diagnostic hybridization methods.

Guo, Zhen (Madison, WI); Smith, Lloyd M. (Madison, WI)

1998-01-01

380

Artificial intelligence system  

Energy Technology Data Exchange (ETDEWEB)

An artificial intelligence system is described for accepting a statement, understanding the meaning of the statement and making a response to the statement based upon at least a partial understanding of the statement. The system comprises: an input means for providing an initial statement and additional statements which provide information for determining the response to the statement; an output means for providing any response to the initial statement and any inquiries requesting additional statements to be inputted on the input means; and a knowledge base having addressable nodes.

Schramm, D.A.

1987-06-02

 
 
 
 
381

Radioactivity in New Zealand meat products  

International Nuclear Information System (INIS)

Full text: New Zealand has no nuclear power programme of radioactive waste disposal programme. The only artificial radioactivity detectable in the New Zealand environment is global fallout from nuclear weapons tests conducted mainly in the northern hemisphere before 1964. This fallout in New Zealand is currently at its lowest level since environmental monitoring began in 1960. The total beta activity deposited in rain during 1985, for example, averaged 76 MBQ/km2, with most of that being due to naturally occurring radionuclides, principally lead-210/Bismuth-210. Levels of artificial radioactivity in New Zealand dairy products reflect this very low deposition rate. During 1985, for example, Strontium-90 and Caesium-137 levels in cow's milk averaged 0.035 BG/GCA and 0.27BQ/QK respectively. Those levels were similar to, or less than, levels reported in northern hemisphere countries during 1985. No change in environmental contamination levels has been recorded in New Zealand during 1985. The very low deposition rate and milk contamination levels indicate that fallout contamination levels generally are insignificant in New Zealand and monitoring of other foodstuffs such as meat products is not warranted. (author)

1987-01-26

382

Generating artificial light curves: Revisited and updated  

CERN Multimedia

The production of artificial light curves with known statistical and variability properties is of great importance in astrophysics. Consolidating the confidence levels during cross-correlation studies, understanding the artefacts induced by sampling irregularities, establishing detection limits for future observatories are just some of the applications of simulated data sets. Currently, the widely used methodology of amplitude and phase randomisation is able to produce artificial light curves which have a given underlying power spectral density (PSD) but which are strictly Gaussian distributed. This restriction is a significant limitation, since the majority of the light curves e.g. active galactic nuclei, X-ray binaries, gamma-ray bursts show strong deviations from Gaussianity exhibiting `burst-like' events in their light curves yielding long-tailed probability distribution functions (PDFs). In this study we propose a simple method which is able to precisely reproduce light curves which match both the PSD an...

Emmanoulopoulos, D; Papadakis, I E

2013-01-01

383

A scenario for a genetically controlled fission of artificial vesicles.  

DEFF Research Database (Denmark)

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

Bönzli, Eva; Hadorn, Maik

384

Radioactivity in consumer products  

Energy Technology Data Exchange (ETDEWEB)

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

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

1978-08-01

385

Radioactive Waste Management.  

Science.gov (United States)

Management of radioactive wastes is necessary to protect public health, public safety, and the environment from radioactive materials resulting from national defense programs, energy research and development, and commercial activities. Access to informati...

1990-01-01

386

Radioactivity and geophysics  

International Nuclear Information System (INIS)

The paper recalls a few steps of the introduction of radioactivity in geophysics and astrophysics: contribution of radioelements to energy balance of the Earth, age of the Earth based on radioactive disintegration and the discovery of cosmic radiations

1992-09-02

387

Radioactive Waste Management.  

Science.gov (United States)

Management of radioactive wastes is necessary to protect public health, public safety, and the environment from radioactive materials resulting from national defense programs, energy research and development, and commercial activities. Access to informati...

1988-01-01

388

Radioactivity in the northern seas of europe  

International Nuclear Information System (INIS)

The recent accidents with nuclear powered Russian submarines, such as the Kursk and the K-159, that took place in the Arctic Seas, give rise to high concerns of the public and the media about the radioactive contamination of marine ecosystems and radiological safety of the European population. Those accidents were preceded by decades of discharges of radioactive liquid effluents into coastal seas of Europe and the dumping of packed radioactive waste into the North Atlantic. Being Portugal one country with high consumption rate of seafood caught in its own coastal waters as well as in far seas including the Ar tic seas, the investigation of the radioactive contamination of fish was investigated. Analysis of fish from the Sea of Labrador, Sea of Iceland and Barents Sea, has shown that gamma-emitting radionuclides of artificial origin are in general not detected. The only gamma emitting radionuclide present is Cs-137, in concentrations not higher than 0.3 Bq/kg. This radionuclide originates in the deposition of radioactive fallout following nuclear weapon tests performed in the fifties and sixties. Radionuclides in fish from northern regions and in fish from the Portuguese coast generally are present in concentrations lower than those currently reported for fish from the Irish Sea and the Baltic Sea, impacted with the discharges of radioactive waste from Sellafield and the deposition of fallout from Chernobyl, respectively. Nevertheless, the potential for future accidents and the radioactive waste dumped into the North Atlantic may in the future modify this scenario and potentially increase the currently very low radionuclide concentration in fish included in the Portuguese diet. Therefore, the research and radiological surveillance must be maintained in order to monitor the radiological risk and to ensure the quality of food available to consumers. (author)

2004-05-01

389

Artificial lung: current perspectives.  

Science.gov (United States)

While the number of the patients suffering from end-stage pulmonary disease has been increasing, the most common treatment for this entity remains mechanical ventilation that entails the risks of lung damage by itself. Although the lung protective strategy for the prevention of further damage to the lung tissue has been elucidated and performed, mechanical ventilation alone as the management tactic coping with the patients of acute respiratory distress syndrome, chronic respiratory failure and lung transplantations has been a frustrated scenario. Extracorporeal membrane oxygenation or extracorporeal lung assist have been applied to these patients with occasional success, but it always accompanies difficulties such as multiple blood transfusion, labor intensity, technically complexity and tendency to infection. In contrast to advances in the development of cardiac or renal support systems for adults, the development of extra-, para- and intracorporeal mechanical systems for acute or chronic lung respiratory failure has logged far behind. It has been mostly due to the lack of the capable technologies. Entering 21st century with advent of new technology especially invention of the low resistance oxygenator, the developments of artificial lungs have entered the new stage. In this report current status of the artificial lungs will be reviewed. PMID:18923347

Go, T; Macchiarini, P

2008-10-01

390

Radioactive consumer products  

Energy Technology Data Exchange (ETDEWEB)

Present situation of utilizing the radioactive consumer products and exposure dose were reviewed with published data. Practically, consumer products are divided into three categories, (1) radioactive nuclides intentionally incorporated into radioluminous dye, ionization chambers for smoke detector, eliminator of static electricity, and glow lamp (2) natural radioactive nuclides contained in false teeth, porcelain, glass, and gas mantle (3) natural radioactive nuclides accumulated as industrial waste at the consumption of coal, petroleum, and natural gas or in fertilizer and materials for construction.

Sato, O. (Tokyo Univ. (Japan). Inst. of Industrial Science)

1981-07-01

391

Radioactive consumer products  

International Nuclear Information System (INIS)

Present situation of utilizing the radioactive consumer products and exposure dose were reviewed with published data. Practically, consumer products are divided into three categories, (1) radioactive nuclides intentionally incorporated into radioluminous dye, ionization chambers for smoke detector, eliminator of static electricity, and glow lamp (2) natural radioactive nuclides contained in false teeth, porcelain, glass, and gas mantle (3) natural radioactive nuclides accumulated as industrial waste at the consumption of coal, petroleum, and natural gas or in fertilizer and materials for construction. (Nakanishi, T.)

1981-07-01

392

Radioactive waste management  

International Nuclear Information System (INIS)

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

1994-01-01

393

Management of radioactive waste  

International Nuclear Information System (INIS)

The document gives an overview of of different aspects of radioactive waste management in Belgium. The document discusses the radioactive waste inventory in Belgium, the treatment and conditioning of radioactive waste as well as activities related to the characterisation of different waste forms. A separate chapter is dedicated to research and development regarding deep geological disposal of radioactive waste. In the Belgian waste management programme, particular emphasis is on studies for disposal in clay. Main results of these studies are highlighted and discussed

1998-01-01

394

New heavy proton radioactivities  

International Nuclear Information System (INIS)

The new proton radioactivities 165,166,167Ir, 171Au, and 185Bi have been observed, extending our knowledge of proton radioactivity up to and beyond the Z=82 closed shell. For Z=77 and 79, the transitions can be explained using simple shell-model arguments. The case of 185Bi represents the first example of proton radioactivity from an intruder state

1995-06-19

395

Understanding radioactive waste  

International Nuclear Information System (INIS)

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

1989-01-01

396

CT staging of lung cancer: the role of artificial pneumothorax  

International Nuclear Information System (INIS)

To determine the role of artificially induced pneumothorax in the evaluation of the chest wall and mediastinal invasion in patients with peripheral bronchogenic carcinoma. CT scans of 22 patients obtained after induced pneumothorax were evaluated. All patients had peripheral lung mass abutting the pleura on a routine CT scan. Room air of 200-400ml was introduced through intrathoracic negative pressure initially, followed by pressure injection through the 18 gauge long bevelled needle under fluoroscopic control. Conclusively, CT with artificial pneumothorax added more information than conventional CT in the evaluation of the chest wall or mediastinal invasion by lung cancer without notable risk

1991-01-01

397

Decomposition of water and production of H2 using semiconductor-photocatalytic effect induced by gamma ray from high radioactive waste  

International Nuclear Information System (INIS)

The technology of the radiolytic decomposition of water leading to hydrogen production was demonstrated to explore a new field in the utilization of radiation and radioactive elements. The technology used consisted of a photoassisted catalytic method which has been generally investigated for photocatalysis using a semiconductor and light in an electrochemical study. In our study, gamma radiation from Co-60 was used instead of light, and a significant amount of evolved hydrogen was detected. Our preliminary experiments proved the possibility of converting the energy ionizing radiation (gamma radiation) into chemical energy (hydrogen) using a semiconductor-photocatalytic effect. (author)

1995-01-01

398

Artificial Ligaments: Promise or Panacea?  

Science.gov (United States)

The Food and Drug Administration has approved a prosthetic ligament for limited use in persons with damaged anterior cruciate ligaments (ACL). This article addresses ligament repair, ACL tears, current treatment, development of the Gore-Tex artificial ligament, other artificial ligaments in process, and arguments for and against their use.…

Lubell, Adele

1987-01-01

399

Packaging of radioactive materials  

International Nuclear Information System (INIS)

The standard describes the packaging rules of radioactive materials (except for fissile materials, spent fuel elements and bulk radioactive materials) for two groups. Type 'A' packaging assures that the radioactive materials should not go loose or spread out in case of an accident. Type 'B' contains additional, more strickt requirements concerning shielding etc. The packaging rules for radioactive materials of unusual shapes are also reported, including qualifications and inspection regulations of packaging regarding radioactive materials of both usual and unusual shape. The latter involves dissolution testing and qualification techniques. The data required in the certificates for the authorities are summarized. (Sz.J.)

1982-01-01

400

Process for storing radioactive waste in ground  

International Nuclear Information System (INIS)

A process for storing radioactive waste in a cavity in the ground is claimed. The waste is conditioned and isolated from the ground by at least one retention barrier. A grout consisting of 1000 parts by weight of water, 40 to 400 parts by weight of cement, 80 to 1000 parts by weight of at least one clay chosen from the group including montmorillonite, illite and vermiculite, as well as 25 to 1200 parts by weight of kieselguhr and/or natural or artificial pozzuolanas is introduced into gaps in the soil areas surrounding the cavity

1981-11-10

 
 
 
 
401

Artificial Immune Systems (2010)  

CERN Document Server

The human immune system has numerous properties that make it ripe for exploitation in the computational domain, such as robustness and fault tolerance, and many different algorithms, collectively termed Artificial Immune Systems (AIS), have been inspired by it. Two generations of AIS are currently in use, with the first generation relying on simplified immune models and the second generation utilising interdisciplinary collaboration to develop a deeper understanding of the immune system and hence produce more complex models. Both generations of algorithms have been successfully applied to a variety of problems, including anomaly detection, pattern recognition, optimisation and robotics. In this chapter an overview of AIS is presented, its evolution is discussed, and it is shown that the diversification of the field is linked to the diversity of the immune system itself, leading to a number of algorithms as opposed to one archetypal system. Two case studies are also presented to help provide insight into the m...

Greensmith, Julie; Aickelin, Uwe

2010-01-01

402

Artificial resuspension studies  

International Nuclear Information System (INIS)

Artificial resuspension studies on a range of Taranaki and other major trial site soils were performed by use of a mechanical dust-raising apparatus. A cascade impactor was used to analyse airborne dust in terms of mass and 241Am activities for particle sizes less than 7 ?m. Plutonium and americium activities were found to be enhanced in the respirable fraction. Reported enhancement factors (defined as the ratio of activity concentration of the respirable fraction to that of the total soil) ranged from 3.7 to 32.5 for Taranaki soils with an average value of 6 appearing reasonable for general application in outer (plume) areas. Values close to unity were measured at major trial sites , One Tree and Tadje. Results of some experiments where uncontamined dust was raised by activities such as walking and driving over dusty ground are also presented. 7 refs., 9 tabs., 4 figs

1990-05-01

403

Hydraulically actuated artificial muscles  

Science.gov (United States)

Hydraulic Artificial Muscles (HAMs) consisting of a polymer tube constrained by a nylon mesh are presented in this paper. Despite the actuation mechanism being similar to its popular counterpart, which are pneumatically actuated (PAM), HAMs have not been studied in depth. HAMs offer the advantage of compliance, large force to weight ratio, low maintenance, and low cost over traditional hydraulic cylinders. Muscle characterization for isometric and isobaric tests are discussed and compared to PAMs. A model incorporating the effect of mesh angle and friction have also been developed. In addition, differential swelling of the muscle on actuation has also been included in the model. An application of lab fabricated HAMs for a meso-scale robotic system is also presented.

Meller, M. A.; Tiwari, R.; Wajcs, K. B.; Moses, C.; Reveles, I.; Garcia, E.

2012-03-01

404

Artificial sweeteners - a review.  

Science.gov (United States)

Now a days sugar free food are very much popular because of their less calorie content. So food industry uses various artificial sweeteners which are low in calorie content instead of high calorie sugar. U.S. Food and Drug Administration has approved aspartame, acesulfame-k, neotame, cyclamate and alitame for use as per acceptable daily intake (ADI) value. But till date, breakdown products of these sweeteners have controversial health and metabolic effects. On the other hand, rare sugars are monosaccharides and have no known health effects because it does not metabolize in our body, but shows same sweet taste and bulk property as sugar. Rare sugars have no such ADI value and are mainly produced by using bioreactor and so inspite of high demand, rare sugars cannot be produced in the desired quantities. PMID:24741154

Chattopadhyay, Sanchari; Raychaudhuri, Utpal; Chakraborty, Runu

2014-04-01

405

Soft computing in artificial intelligence  

CERN Multimedia

This book explores the concept of artificial intelligence based on knowledge-based algorithms. Given the current hardware and software technologies and artificial intelligence theories, we can think of how efficient to provide a solution, how best to implement a model and how successful to achieve it. This edition provides readers with the most recent progress and novel solutions in artificial intelligence. This book aims at presenting the research results and solutions of applications in relevance with artificial intelligence technologies. We propose to researchers and practitioners some methods to advance the intelligent systems and apply artificial intelligence to specific or general purpose. This book consists of 13 contributions that feature fuzzy (r, s)-minimal pre- and ?-open sets, handling big coocurrence matrices, Xie-Beni-type fuzzy cluster validation, fuzzy c-regression models, combination of genetic algorithm and ant colony optimization, building expert system, fuzzy logic and neural network, ind...

Matson, Eric

2014-01-01

406

Conservative smoothing versus artificial viscosity  

Energy Technology Data Exchange (ETDEWEB)

This report was stimulated by some recent investigations of S.P.H. (Smoothed Particle Hydrodynamics method). Solid dynamics computations with S.P.H. show symptoms of instabilities which are not eliminated by artificial viscosities. Both analysis and experiment indicate that conservative smoothing eliminates the instabilities in S.P.H. computations which artificial viscosities cannot. Questions were raised as to whether conservative smoothing might smear solutions more than artificial viscosity. Conservative smoothing, properly used, can produce more accurate solutions than the von Neumann-Richtmyer-Landshoff artificial viscosity which has been the standard for many years. The authors illustrate this using the vNR scheme on a test problem with known exact solution involving a shock collision in an ideal gas. They show that the norms of the errors with conservative smoothing are significantly smaller than the norms of the errors with artificial viscosity.

Guenther, C.; Hicks, D.L. [Michigan Technological Univ., Houghton, MI (United States); Swegle, J.W. [Sandia National Labs., Albuquerque, NM (United States). Solid and Structural Mechanics Dept.

1994-08-01

407

Few-electron artificial atoms  

International Nuclear Information System (INIS)

Artificial atoms. i.e., bound systems of excess electrons confined in semiconductor quantum dots, are studied by the variational and Hartree-Fock methods. The confinement potential is assumed to have the form of a spherical potential well of finite depth, which provides a theoretical model for electron states in a spherical semiconductor nanocrystal embedded in an insulating matrix. For the two- and three-electron artificial atoms, we have applied the variational method and obtained the binding of both the ground states and excited states. The Hartree-Fock method has been applied to the N-electron artificial atoms with N = 1,...., 20. It is shown that the shells of the artificial atoms are filled by electrons in the same manner like those of the natural atoms. In particular, Hund's rule is fulfilled. The radial probability density calculated for artificial atoms is different from that for natural atoms. Refs. 14, figs. 4 (author)

1998-06-01

408

Study of radioactive contamination of Eastern Poland  

Energy Technology Data Exchange (ETDEWEB)

Studies of the contamination of soils of Eastern Poland with natural and artificial radionuclides lead to a conclusion that human activities have caused a visible increase of contamination with natural radionuclides. The fallout from ash from coal combustion is the main source. This factor also causes the irregular distribution of the radionuclides over the studied area. This effect is enhanced due to different sorption properties of the soils. The main radionuclide defining the radioactivity of the soils of eastern Poland is K-40 the contribution of which ranges from 55 to 70 and even 75% of the total