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Abstract  

A simple analytical method was developed for the determination of cosmogenic 22Na radionuclide in fresh water samples by ultra low-background g-ray spectrometry after radiochemical separation. The method consists in pre-concentration of 22Na(Na) by a ion exchange resin column from a large volume of ca. 500-liter water samples, elution with 4M HCl from the resin, and removal of the main metal components such as Ca and Mg as carbonate precipitates and of 40K(K) as potassium tetraphenylborate K[B(C6H5)4]. The obtained 22Na fraction was successfully measured by an ultra low-background Ge detector installed in the Ogoya Underground Laboratory.

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Abstract  

The concentration of pore water uranium in six sediments from oligotrophic, mesotrophic, acidotrophic and dystrophic lakes was measured by inductively coupled plasma-mass spectrometry. Profiles of pore water U can be divided into two groups such as low (17±7 ng/l) and high concentration (69±30 ng/l). These values were 1–2 orders of magnitude higher than that of lake waters (6±4 ng/l) due to the release of U from the sediments by decomposition of organic materials. Variations in pore water U concentrations seem to relate to the differences in pore water pH, the association forms, and their contents of U in the lake sediments.

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Abstract  

The concentrations of210Po and210Pb were determined in about 30 species of marine organisms collected mainly from the north-easterm region of Japan to know the levels and distributions of these radionuclides and to estimate their intake levels from marine foods.210Po and210Pb showed a wide range of concentration in species: 0.6–26 and 0.04–0.54 Bq/kg (wet wt) in fishes, 0.5–220 and 0.2–43 Bq/kg (wet wt) in molluscs, echinoderms and chordatas, and 2.8–4.3 and 0.4–1.3 Bq/kg (wet wt) in algae, respectively. Higher accumulation of210Po relative to210Pb was found in all of the samples analyzed. The intake levels of210Po and210Pb by marine foods consumption were roughly estimated to be 0.48–0.69 and 0.022–0.042 Bq/d per person, respectively, on the basis of the statistical data on the consumption of seafood and/or production rates of marine foods.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
K. Shiraishi
,
Y. Muramatsu
,
T. Nakajima
,
M. Yamamoto
,
I. Los
,
I. Kamarikov
, and
M. Buzinny

Abstract  

Many kinds of environmental samples including total diet samples, were collected in the Chernobyl (Ukraine) vicinity and in Ibaraki prefecture (Japan). Six radionuclides and twelve stable elements were analyzed. After samples were dry-ashed, radioactivities of137Cs,134Cs,40K,60Co and54Mn were determined by -ray spectroscopy with a germanium detector. Strontium-90 was determined by low-background -spectrometry. Stable elements were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Comparison of the levels of radionuclides between the Ukraine and Ibaraki showed the former were several times to a few tens of thousands of times higher than the latter, depending on the samples.

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Abstract  

Approximately 100 freshwater samples were collected in Ukraine, Russia, and Belorussia with regard to the Chernobyl accident. Thorium and uranium were determined by both quantitative and semiquantitative analysis modes of inductively coupled plasma mass spectrometry (ICP-MS). Thorium-232 was detected in only a few samples. Uranium concentrations ranged from non-detectable to 1,000ng/ml. Mean and median concentrations of238U were found to be 30.7±139 and 0.7 ng/ml, respectively. The isotope ratio of234U/238U ranged from 4.6·10–5 to 4.4·10–4. Mean ratio of235U/238U was 0.00721±0.00006 (n=27).

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Abstract  

In order to investigate the sedimentary behaviour of neptunium,237Np together with Pu isotopes and241Am have been measured for the sediment cores collected from Lake Mikata (freshwater) and from Lake Kugushi (brakish water) both belonging to the Mikata Five Lakes, and from Nyu Bay (sea water). In all sediment core samples237Np was detected, and its concentrations were far below those of239,240Pu and241Am measured for the same samples. Inventories of237Np in Lake Mikata, Lake Kugushi and Nyu Bay were estimated to be 0.53, 0.29 and 0.34 MBq/km2, respectively. The activity ratio of237Np/239,240Pu calculted from the inventories in each sediment core was 0.29% for Lake Mikata, 0.15% for Lake Kugushi and 0.10% for Nyu Bay. These values except for the value for Lake Mikata are two or three times lower than the value of 0.3–0.4% observed for surface soils of 0–20 cm depth, suggesting that Np is more soluble compared with Pu.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
Y. Suzuki
,
T. Nankawa
,
T. Yoshida
,
T. Ozaki
,
T. Ohnuki
,
A. J. Francis
,
S. Tsushima
,
Y. Enokida
, and
I. Yamamoto

Summary  

We have investigated the structure of Eu(III)-citrate complexes in aqueous solution and their degradability by Pseudomonas fluorescens. Analysis of 1:1, 1:2, and 1:5 Eu(III):citrate solutions at pH 7 by electrospray ionization mass spectrometry (ESI-MS) showed that the 2:2 Eu(III)-citrate complex is the predominant complex species at a low citrate/Eu(III) ratio, while at a high ratio, a 1:2 Eu(III)-citrate complex is formed preferably. Studies on the biodegradation of Eu(III)-citrate complex by P. fluorescens have shown that a 2:2 Eu(III)-citrate complex is resistent to degradation while a 1:2 complex transforms to a 2:2 complex with the degradation of excess citric acid.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
D. Assinder
,
M. Yamamoto
,
C. Kim
,
R. Seki
,
Y. Takaku
,
Y. Yamauchi
,
S. Igarashi
,
K. Komura
, and
K. Ueno

Abstract  

A survey has been carried out of40K,60Co,99Tc,106Ru,125Sb,129I,134Cs,137Cs,154Eu,226Ra,228Ra,237Np,238Pu,239,240Pu,241Pu,241Am,242Cm, and243,244Cm activities in sediments from the Irish Sea. Several of these radionuclides were measured independently at two separate laboratories to enable the intercomparison of the results produced. The comprehensive data set generated allows the present spatial distributions of these radionuclides in coastal sediments to be examined in relation to sediment textural characteristics and by comparison with earlier survey, enables the temporal trends in their activities to be determined. In general all artificial radionuclides showed lower activities in sediments in response to falling discharges from Sellafield and relationships with either grain size, distance from Sellafield or both. Isotope ratios were similar to cumulative weighted activity ratios rather than present day values due to sediment mixing. Pu levels supplied evidence for the lag in response of sediment deposits with increasing distance from Sellafield due to sediment transport.

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Acta Botanica Hungarica
Authors:
S. Y. Kondratyuk
,
J. P. Halda
,
L. Lőkös
,
Y. Yamamoto
,
L. P. Popova
, and
J.-S. Hur

Six new for science species of lichen-forming fungi from Republic of Korea, Eastern Asia, i. e.: Bacidina jasonhuri J. P. Halda, S. Y. Kondr. et L. Lőkös, Gyalidea koreana J. P. Halda, S. Y. Kondr. L. Lőkös et Hur, G. pisutii J. P. Halda, S. Y. Kondr. L. Lőkös et Hur, G. poeltii S. Y. Kondr. L. Lőkös, J. P. Halda et Hur, G. Vězdae S. Y. Kondr. L. Lőkös, J. P. Halda et Hur, and Porpidia ulleungdoensis S. Y. Kond. L. Lőkös et J. P. Halda, as well as two new species from Japan (Fauriea yonaguniensis S. Y. Kondr. M. Moriguchi et Yoshik. Yamam. and Laundonia ryukyuensis S. Y. Kondr. M. Moriguchi et Yoshik. Yamam.), and one new species Lecanora orlovii S. Y. Kondr. et L. Lőkös from Ukraine are described, illustrated and compared with closely related taxa.

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Acta Botanica Hungarica
Authors:
S. Y. Kondratyuk
,
L. Lőkös
,
E. Farkas
,
I. Kärnefelt
,
A. Thell
,
Y. Yamamoto
, and
J.-S. Hur

Three new for science genera, i.e.: Erichansenia S. Y. Kondr., Kärnefelt et A. Thell for the ‘Caloplaca’ epithallina group of the subfamily Xanthorioideae, as well as Lendemeriella S. Y. Kondr. for the Caloplaca reptans group, and Pisutiella S. Y. Kondr., L. Lőkös et E. Farkas for the Caloplaca conversa group of the subfamily Caloplacoideae of the Teloschistaceae, are described on the basis of results of the three gene phylogeny of the Teloschistaceae based on nrITS, nrLSU and mtSSU sequences.

Twenty-seven new combinations, i.e.: Erichansenia epithallina (for Caloplaca epithallina Lynge), Erichansenia cryodesertorum (for Shackletonia cryodesertorum Garrido-Ben., Søchting et Pérez-Ort.), Erichansenia sauronii (for Caloplaca sauronii Søchting et Øvstedal), Fauriea mandshuriaensis (for Caloplaca mandshuriaensis S. Y. Kondr., L. Lőkös et J.-S. Hur), Fauriea trassii (for Caloplaca trassii Galanina et S. Y. Kondr.), Lendemeriella borealis (for Lecanora pyracea f. borealis Vain.), Lendemeriella dakotensis (for Caloplaca dakotensis Wetmore), Lendemeriella exsecuta (for Lecanora exsecuta Nyl.), Lendemeriella lucifuga (for Caloplaca lucifuga G. Thor), Lendemeriella nivalis (for Zeora nivalis Körb.), Lendemeriella reptans (for Caloplaca reptans Lendemer et B. P. Hodk.), Lendemeriella sorocarpa (for Placodium sorocarpum Vain.), Lendemeriella tornoensis (for Caloplaca tornoensis H. Magn.), Pisutiella congrediens (for Lecanora congrediens Nyl.), Pisutiella conversa (for Callopisma conversum Kremp.), Pisutiella furax (for Caloplaca furax Egea et Llimona), Pisutiella grimmiae (for Lecanora grimmiae Nyl.), Pisutiella ivanpisutii (for Caloplaca ivanpisutii S. Y. Kondr., L. Lőkös et Hur), Pisutiella phaeothamnos (for Caloplaca phaeothamnos K. Kalb et J. Poelt), Pyrenodesmia aetnensis (for Caloplaca aetnensis B. de Lesd.), Pyrenodesmia albolutescens (for Lecanora albolutescens Nyl.), Pyrenodesmia aractina (for Parmelia aractina Fr.), Pyrenodesmia atroflava (for Lecidea atroflava Turner), Pyrenodesmia bicolor (for Caloplaca bicolor H. Magn.), Pyrenodesmia molariformis (for Caloplaca molariformis Frolov, Vondrák, Nadyeina et Khodos.), Pyrenodesmia neotaurica (for Caloplaca neotaurica Vondrák, Khodos., Arup et Søchting), Pyrenodesmia peliophylla (for Placodium peliophyllum Tuck.) are proposed based on results from a combined phylogenetic analysis using nrITS, nrLSU and mtSSU gene sequences.

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