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C25H18CuN5O4, triclinic, P1̅ (no. 2), a = 7.300(1) Å, b = 11.985(1) Å, c = 13.190(1) Å, α = 88.15(1)°, β = 78.68(1)°, γ = 78.62(1)°, V = 1109.3 Å3, Z = 2, Rgt(F) = 0.048, wRref(F2) = 0.134, T = 293 K.

Radiocarbon variations in the atmosphere have been observed at the Žlkovce monitoring station of the Bohunice nuclear power plant (NPP), situated only 5 km ESE from the NPP. The observed 14C levels provide unique evidence of a decreasing long-term impact of the Bohunice NPP on the region. Simultaneously, decreasing emissions of fossil fuel carbon dioxide in the atmosphere of the monitoring site have been found. The observed Δ14C variations with time have attenuating amplitudes and decreasing mean values, showing maxima in summer and minima in winter, the latter primarily caused by increased emission of fossil CO2 in winter months. Sporadic short-term releases of 14C from the Bohunice NPP were observed at the Žlkovce station. The annual atmospheric Δ14C variations compared with tree-ring data collected at the Žlkovce village show reasonable agreement. The observed Δ14C levels after 2005 are close to the European clean-air levels as measured at the Jungfraujoch (3450 m asl) monitoring station. [ABSTRACT FROM AUTHOR]

Radionuclide impact of the Fukushima Dai-ichi nuclear power plant accident on the distribution of radionu-clides in seawater of the NW Pacific Ocean is compared with global fallout from atmospheric tests of nuclear weapons. Surface and water column samples collected during the Ka'imikai-o-Kanaloa (KOK) international expedition carried out in June 2011 were analyzed for 134Cs, 137Cs, 129I and ³H. The 137Cs, 129I and ³H levels in surface seawater offshore Fukushima varied between 0.002-3.5Bq L-1, 0.01-0.8 uBq L-1, and 0.05-0.15 Bq L-1, respectively. At the sampling site about 40 km from the coast, where all three radionuclides were analyzed, the Fukushima impact on the levels of these three radionuclides represents an increase above the global fallout background by factors of about 1000, 50 and 3, respectively. The water column data indicate that the transport of Fukushima-derived radionuclides downward to the depth of 300 m has already occurred. The observed 137Cs levels in surface waters and in the water column are compared with predictions obtained from the ocean general circulation model, which indicates that the Kuroshio Current acts as a southern boundary for the transport of the radionuclides, which have been transported from the Fukushima coast eastward in the NW Pacific Ocean. The 137Cs inventory in the water column is estimated to be about 2.2 PBq, what can be regarded as a lower limit of the direct liquid discharges into the sea as the seawater sampling was carried out only in the area from 34 to 37° N, and from 142 to 147° E. About 4.6 GBq of 129I was deposited in the NW Pacific Ocean, and 2.4-7 GBq of 129I was directly discharged as liquid wastes into the sea offshore Fukushima. The total amount of ³H released and deposited over the NW Pacific Ocean was estimated to be 0.1-0.5 PBq. These estimations depend, however, on the evaluation of the total 137Cs activities released as liquid wastes directly into the sea, which should improve when more data are available. Due to a suitable residence time in the ocean, Fukushima-derived radionuclides will provide useful tracers for isotope oceanography studies on the transport of water masses during the next decades in the NW Pacific Ocean. [ABSTRACT FROM AUTHOR]