The Experts below are selected from a list of 228 Experts worldwide ranked by ideXlab platform
Xiaolin Hou - One of the best experts on this subject based on the ideXlab platform.
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Iodine 129 in seawater offshore fukushima distribution inorganic speciation sources and budget
Environmental Science & Technology, 2013Co-Authors: Xiaolin Hou, Pavel P. Povinec, L Zhang, Keliang Shi, D Biddulph, Chingchih Chang, Yukun Fan, Robin Golser, Yingkun Hou, M JeskovskýAbstract:The Fukushima nuclear accident in March 2011 has released a large amount of radioactive pollutants to the environment. Of the pollutants, Iodine-129 is a long-lived radionuclide and will remain in the environment for millions of years. This work first report levels and inorganic speciation of 129I in seawater depth profiles collected offshore Fukushima in June 2011. Significantly elevated 129I concentrations in surface water were observed with the highest 129I/127I atomic ratio of 2.2 × 10–9 in the surface seawater 40 km offshore Fukushima. Iodide was found as the dominant species of 129I, while stable 127I was mainly in iodate form, reflecting the fact that the major source of 129I is the direct liquid discharges from the Fukushima NPP. The amount of 129I directly discharged from the Fukushima Dai-ichi nuclear power plant to the sea was estimated to be 2.35 GBq, and about 1.09 GBq of 129I released to the atmosphere from the accident was deposited in the sea offshore Fukushima. A total release of 8.06 GBq...
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Iodine-129 enrichment in sediment of the Baltic Sea
Applied Geochemistry, 2007Co-Authors: Ala Aldahan, Göran Possnert, Edvard Englund, Ingemar Cato, Xiaolin HouAbstract:Sediments are an excellent archive for evaluation of time-series environmental contamination of water systems. Measurements of ultra-trace radioactive species, such as 129I, provide information for ...
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Iodine-129 in thyroid and urine in Ukraine and Denmark.
The Science of the total environment, 2003Co-Authors: Xiaolin Hou, Henning Dahlgaard, J. Kucera, A F Malencheko, S P NielsenAbstract:Human thyroids collected from Gomel in Belarus, sheep thyroid from Jutland and human urine from Zealand in Denmark were analysed for 129I and 127I concentrations. The ratios of 129I/127I in human thyroid in Gomel are 2.65-11.0 x 10(-9) with an average of 7.21 x 10(-9), which is one order of magnitude higher than those from Asia and South America (10(-10)), but significantly lower than those observed in west Europe (10(-8)). A weak negative correlation (P < 0.05) between 129I/127I ratio in human thyroid and the age of the subjects was observed in Gomel. The average ratio of 129I/127I in sheep thyroids from Jutland of Denmark is 1.81 x 10(-7), which is two orders of magnitude higher than those in south hemisphere, and Asia. It is also significantly higher than those observed in other west European countries before 1984 and that in human thyroid in Gomel. The high thyroid 129I level in Jutland is attributed to the release of reprocessing plants in France and UK. The 129I/127I ratios in human urine in Zealand of Denmark are 0.86-2.86 x 10(-8). The possibility of using urine 129I to evaluate the thyroid exposure to 129I is investigated.
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Iodine-129 in thyroid and urine in Ukraine and Denmark.
Science of The Total Environment, 2002Co-Authors: Xiaolin Hou, Henning Dahlgaard, J. Kucera, A F Malencheko, Sven Poul NielsenAbstract:Abstract Human thyroids collected from Gomel in Belarus, sheep thyroid from Jutland and human urine from Zealand in Denmark were analysed for 129 I and 127 I concentrations. The ratios of 129 I/ 127 I in human thyroid in Gomel are 2.65–11.0×10 −9 with an average of 7.21×10 −9 , which is one order of magnitude higher than those from Asia and South America (10 −10 ), but significantly lower than those observed in west Europe (10 −8 ). A weak negative correlation ( P 129 I/ 127 I ratio in human thyroid and the age of the subjects was observed in Gomel. The average ratio of 129 I/ 127 I in sheep thyroids from Jutland of Denmark is 1.81×10 −7 , which is two orders of magnitude higher than those in south hemisphere, and Asia. It is also significantly higher than those observed in other west European countries before 1984 and that in human thyroid in Gomel. The high thyroid 129 I level in Jutland is attributed to the release of reprocessing plants in France and UK. The 129 I/ 127 I ratios in human urine in Zealand of Denmark are 0.86–2.86×10 −8 . The possibility of using urine 129 I to evaluate the thyroid exposure to 129 I is investigated.
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Level and origin of Iodine-129 in the Baltic Sea.
Journal of environmental radioactivity, 2002Co-Authors: Xiaolin Hou, Henning Dahlgaard, Sven Poul Nielsen, J. KuceraAbstract:Abstract Environmental samples, such as seawater, seaweed, lake water, lake sediment and grass collected from the Baltic Sea area were analyzed for 129 I and 127 I by radiochemical neutron activation analysis. In 2000, the concentration of 129 I in the seawater from Borholm and Moen in the Baltic Sea has reached 6.0×10 −13 and 16×10 −13 g/l, respectively, these are more than two orders of magnitude higher than the global fallout level. The highest value of 270×10 −13 g/l being found in the seawater from the Kattegat. By comparison of the level of 129 I in the lake water and precipitation in this region, it is estimated that more than 95% of 129 I in the Baltic Sea originates from reprocessing emissions, especially from the French nuclear fuel reprocessing plant at La Hague. More than 30% of 129 I in the south Baltic and 93% in the Kattegat directly originates from the marine discharges of the European reprocessing plants.
Junzo Tanaka - One of the best experts on this subject based on the ideXlab platform.
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Novel Long-Term Immobilization Method for Radioactive Iodine-129 Using a Zeolite/Apatite Composite Sintered Body
ACS applied materials & interfaces, 2009Co-Authors: Yujiro Watanabe, Toshiyuki Ikoma, Hirohisa Yamada, Yasushi Suetsugu, Yu Komatsu, Geoffrey W. Stevens, Yusuke Moriyoshi, Junzo TanakaAbstract:The amount of radioactive Iodine generated from nuclear power plants is expected to increase with the proliferation of nuclear energy production, and long-term immobilization methods for such radioactive elements need to be developed to make nuclear energy sustainable. The standard immobilization method of radioactive elements, vitrification, is not very effective for radioactive Iodine-129 because of the low solubility of Iodine in silicate melts, its very high volatility at standard vitrification process temperatures, and its instability in the alkaline environment of deep geological layers below 300 m. We have developed a novel three-phase ceramic composite produced by a sintering process. Iodine adsorbed onto Ca-type zeolite A was covered with a hydroxyapatite nanolayer through the exchange reaction of ammonium with calcium. Clusters of Iodine of 30 nm within the zeolite structure were found to be thermally stable up to 1253 K because of the partial blockage of the α-cage apertures by ammonium ions an...
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novel long term immobilization method for radioactive Iodine 129 using a zeolite apatite composite sintered body
ACS Applied Materials & Interfaces, 2009Co-Authors: Yujiro Watanabe, Toshiyuki Ikoma, Hirohisa Yamada, Yasushi Suetsugu, Yu Komatsu, Geoffrey W. Stevens, Yusuke Moriyoshi, Junzo TanakaAbstract:The amount of radioactive Iodine generated from nuclear power plants is expected to increase with the proliferation of nuclear energy production, and long-term immobilization methods for such radioactive elements need to be developed to make nuclear energy sustainable. The standard immobilization method of radioactive elements, vitrification, is not very effective for radioactive Iodine-129 because of the low solubility of Iodine in silicate melts, its very high volatility at standard vitrification process temperatures, and its instability in the alkaline environment of deep geological layers below 300 m. We have developed a novel three-phase ceramic composite produced by a sintering process. Iodine adsorbed onto Ca-type zeolite A was covered with a hydroxyapatite nanolayer through the exchange reaction of ammonium with calcium. Clusters of Iodine of 30 nm within the zeolite structure were found to be thermally stable up to 1253 K because of the partial blockage of the α-cage apertures by ammonium ions an...
Yujiro Watanabe - One of the best experts on this subject based on the ideXlab platform.
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Novel Long-Term Immobilization Method for Radioactive Iodine-129 Using a Zeolite/Apatite Composite Sintered Body
ACS applied materials & interfaces, 2009Co-Authors: Yujiro Watanabe, Toshiyuki Ikoma, Hirohisa Yamada, Yasushi Suetsugu, Yu Komatsu, Geoffrey W. Stevens, Yusuke Moriyoshi, Junzo TanakaAbstract:The amount of radioactive Iodine generated from nuclear power plants is expected to increase with the proliferation of nuclear energy production, and long-term immobilization methods for such radioactive elements need to be developed to make nuclear energy sustainable. The standard immobilization method of radioactive elements, vitrification, is not very effective for radioactive Iodine-129 because of the low solubility of Iodine in silicate melts, its very high volatility at standard vitrification process temperatures, and its instability in the alkaline environment of deep geological layers below 300 m. We have developed a novel three-phase ceramic composite produced by a sintering process. Iodine adsorbed onto Ca-type zeolite A was covered with a hydroxyapatite nanolayer through the exchange reaction of ammonium with calcium. Clusters of Iodine of 30 nm within the zeolite structure were found to be thermally stable up to 1253 K because of the partial blockage of the α-cage apertures by ammonium ions an...
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novel long term immobilization method for radioactive Iodine 129 using a zeolite apatite composite sintered body
ACS Applied Materials & Interfaces, 2009Co-Authors: Yujiro Watanabe, Toshiyuki Ikoma, Hirohisa Yamada, Yasushi Suetsugu, Yu Komatsu, Geoffrey W. Stevens, Yusuke Moriyoshi, Junzo TanakaAbstract:The amount of radioactive Iodine generated from nuclear power plants is expected to increase with the proliferation of nuclear energy production, and long-term immobilization methods for such radioactive elements need to be developed to make nuclear energy sustainable. The standard immobilization method of radioactive elements, vitrification, is not very effective for radioactive Iodine-129 because of the low solubility of Iodine in silicate melts, its very high volatility at standard vitrification process temperatures, and its instability in the alkaline environment of deep geological layers below 300 m. We have developed a novel three-phase ceramic composite produced by a sintering process. Iodine adsorbed onto Ca-type zeolite A was covered with a hydroxyapatite nanolayer through the exchange reaction of ammonium with calcium. Clusters of Iodine of 30 nm within the zeolite structure were found to be thermally stable up to 1253 K because of the partial blockage of the α-cage apertures by ammonium ions an...
Sven Poul Nielsen - One of the best experts on this subject based on the ideXlab platform.
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Iodine-129 in thyroid and urine in Ukraine and Denmark.
Science of The Total Environment, 2002Co-Authors: Xiaolin Hou, Henning Dahlgaard, J. Kucera, A F Malencheko, Sven Poul NielsenAbstract:Abstract Human thyroids collected from Gomel in Belarus, sheep thyroid from Jutland and human urine from Zealand in Denmark were analysed for 129 I and 127 I concentrations. The ratios of 129 I/ 127 I in human thyroid in Gomel are 2.65–11.0×10 −9 with an average of 7.21×10 −9 , which is one order of magnitude higher than those from Asia and South America (10 −10 ), but significantly lower than those observed in west Europe (10 −8 ). A weak negative correlation ( P 129 I/ 127 I ratio in human thyroid and the age of the subjects was observed in Gomel. The average ratio of 129 I/ 127 I in sheep thyroids from Jutland of Denmark is 1.81×10 −7 , which is two orders of magnitude higher than those in south hemisphere, and Asia. It is also significantly higher than those observed in other west European countries before 1984 and that in human thyroid in Gomel. The high thyroid 129 I level in Jutland is attributed to the release of reprocessing plants in France and UK. The 129 I/ 127 I ratios in human urine in Zealand of Denmark are 0.86–2.86×10 −8 . The possibility of using urine 129 I to evaluate the thyroid exposure to 129 I is investigated.
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Level and origin of Iodine-129 in the Baltic Sea.
Journal of environmental radioactivity, 2002Co-Authors: Xiaolin Hou, Henning Dahlgaard, Sven Poul Nielsen, J. KuceraAbstract:Abstract Environmental samples, such as seawater, seaweed, lake water, lake sediment and grass collected from the Baltic Sea area were analyzed for 129 I and 127 I by radiochemical neutron activation analysis. In 2000, the concentration of 129 I in the seawater from Borholm and Moen in the Baltic Sea has reached 6.0×10 −13 and 16×10 −13 g/l, respectively, these are more than two orders of magnitude higher than the global fallout level. The highest value of 270×10 −13 g/l being found in the seawater from the Kattegat. By comparison of the level of 129 I in the lake water and precipitation in this region, it is estimated that more than 95% of 129 I in the Baltic Sea originates from reprocessing emissions, especially from the French nuclear fuel reprocessing plant at La Hague. More than 30% of 129 I in the south Baltic and 93% in the Kattegat directly originates from the marine discharges of the European reprocessing plants.
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Iodine-129 in human thyroids and seaweed in China.
The Science of the total environment, 2000Co-Authors: Xiaolin Hou, Henning Dahlgaard, Sven Poul Nielsen, Wenjun DingAbstract:Abstract The concentrations of 129 I and the ratios of 129 I/ 127 I in normal human thyroids collected in Tianjin, China, and some seaweed samples from the Chinese coast were determined by neutron activation analysis. The mean 129 I/ 127 I ratio in these thyroids was found to be 1.13×10 −9 , which is two orders of magnitude higher than the level of the pre-nuclear era, but one order of magnitude lower than the level in Europe in the post-nuclear era. There is no significant difference between the ratio of 129 I/ 127 I in the thyroids for the post-nuclear era from China and other areas, which are considered not to have been directly exposed to 129 I emission from a nuclear source, such as Chile, Taiwan and Tokyo. The mean 129 I/ 127 I ratio in seaweed from the Chinese coast is 2.35×10 −10 , approximately two orders of magnitude higher than in seaweed collected in the pre-nuclear age, and similar to that from locations without direct exposure to the emission from nuclear installations, influenced only by global fallout. This indicates that the 129 I level in China is within the global fallout background level.
Göran Possnert - One of the best experts on this subject based on the ideXlab platform.
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Distribution of 129I in terrestrial surface water environments
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2015Co-Authors: Xuegao Chen, Göran Possnert, Ala Aldahan, Meng Gong, Li ChenAbstract:The global distribution of the radioactive isotope Iodine-129 in surface waters (lakes and rivers) is presented here and compared with the atmospheric deposition and distribution in surface marine waters. The results indicate relatively high concentrations in surface water systems in close vicinity of the anthropogenic release sources as well as in parts of Western Europe, North America and Central Asia. I-129 level is generally higher in the terrestrial surface water of the Northern hemisphere compared to the southern hemisphere. The highest values of I-129 appear around 50 degrees N and 40 degrees S in the northern and southern hemisphere, separately. Direct gaseous and marine atmospheric emissions are the most likely avenues for the transport of 1291 from the sources to the terrestrial surface waters. To apply Iodine-129 as process tracer in terrestrial surface water environment, more data are needed on I-129 distribution patterns both locally and globally.
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Water masses and 129I distribution in the Nordic Seas
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms, 2013Co-Authors: Vasily Alfimov, Ala Aldahan, Göran PossnertAbstract:The application of the radioactive isotope Iodine-129 as a tracer of water circulation in the oceans has provided interesting information with respect to sources and mixing of different water masse ...
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Iodine-129 enrichment in sediment of the Baltic Sea
Applied Geochemistry, 2007Co-Authors: Ala Aldahan, Göran Possnert, Edvard Englund, Ingemar Cato, Xiaolin HouAbstract:Sediments are an excellent archive for evaluation of time-series environmental contamination of water systems. Measurements of ultra-trace radioactive species, such as 129I, provide information for ...
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Anthropogenic Iodine-129 in the Arctic Ocean and Nordic Seas: numerical modeling and prognoses.
Marine pollution bulletin, 2005Co-Authors: Vasely Alfimov, Göran Possnert, Ala AldahanAbstract:Anthropogenic Iodine-129 in the Arctic Ocean and Nordic Seas: Numerical modeling and prognoses
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Anthropogenic Iodine-129 in seawater along a transect from the Norwegian coastal current to the North Pole
Marine Pollution Bulletin, 2004Co-Authors: Vasily Alfimov, Göran Possnert, Ala Aldahan, Peter WinsorAbstract:Anthropogenic Iodine-129 in seawater along a transect from the Norwegian coastal current to the North Pole
