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Sulfur dioxide (SO₂) is one of the many trace gases present in the atmosphere. The photodissociation reaction by UV light initiates a complicated oxidation process which its final product sulfates and sulfuric acid form aerosols. This chemical process is complemented by physical deposition which brings back sulfate aerosols to earth to become part of the soil and rocks. The photodissociation process is assumed to imprint a characteristic isotopic fractionation highly dependent on wavelength therefore the sulfates contained in rocks from different geological ages would have a characteristic isotopic fractionation of the atmospheric radiactive conditions of that age. Previously recorded UV absorption spectra of ³²SO₂, ³³SO₂, ³⁴SO₂ (Danielache et al., 2008) have been used to interpret the geological record. Due to UV shielding, atmospheric concentrations of O₂, O₃, OCS, ₂, H₂O, and SO₂ influence on isotopic fractionations and contribute to the mass independent fractionation (MIF) observed in rocks from the beginning of earth up to 2.4 billion years before present, also called Archaean MIF (Ueno et al., 2009).In this study we report ^32,33,34&36SO₂ spectra calculated wavepacket dynamics with a newly developed method that take into account non-adiabatic transitions, furthermore the implemented methodology has been constructed to reproduce a, yet to be measured, rotationally resolved spectra and by optimizing the absorption width of each transition to the Doppler limit and its pressure variation we construct spectra suitable to specific atmospheric conditions. The obtained data sets opens the enable us to study self-shielding mechanisms for a wide range of scenarios.

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In the natural world,there is isotope fractionation. One of the isotope fractionation has ion exchange reaction. By the isotope effect, I report the isotope effect between each isotope from an isotope separation experiment using the chromatography of iron, nickel and lead.

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Ninety eight drinking groundwater samples collected from different depths of Cox's Bazar paleo-beach and the hills behind the beach were analyzed using ICP-MS for contents of U and Th together with minor and major chemical components. About 4% of studied shallow tubewells (<30m in depth) contained excess U from the WHO drinking water guideline, 2.0 ug/l, which were mainly found at paleo-beach sites.

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Groundwater and river water chemistry in Miyagi Prefecture were investigated in relation to Tsunami occurred in the 11th of March 2011. The samples ware taken from the March to November 2012. Groundwater in the inland area was rarely affected by anthropogenic activities. Salinization (~500 mg/L Cl) was occasionally observed in shallow groundwaters of the Tsunami affected area. Metal contamination in those groundwaters was not serious except Fe and Mn, which would be released via reduction of sulfate in the seawater.

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Since Ln(III) of LnVO₄(tet.) series has smaller Racah parameters thanfree Ln(III) ion, the lattice enthalpies of LnVO₄(tet.) series are expected to show a convex tetrad effect like those of Ln2O3(cub). On the equilibrium conditions for the lattice enthalpy for LnVO₄(tet.). this tetrad effect reflects in the series changes of lattice constants and Ln-O distances in LnVO₄(tet.) series.

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Water-rich plumes with sodium salts erupting from warm fractures near the south pole of Saturn's icy moon Enceladus suggest the presence of a liquid-water reservoir in the interior. The findings of silica nanoparticles in Saturn's E-ring derived from the plumes imply active geochemistry involving water-rock interactions. It is however highly unknown the particular conditions of temperature, pH, and mineral compositions that can sustain the formation of silica in Enceladus. Here we report laboratory experiments and calculation of hydrothermal reactions simulating Enceladus' interior. To achieve high silica concentrations in the fluids, hydrous silicates of Enceladus' core would be composed mainly of serpentine and saponite (or talc at higher temperatures), consistent with chondritic compositions of its rocky core. To form silica nanoparticles in Enceladus, the fluid temperature needs to reach ? 150?200°C, suggesting extensive hydrothermal activity. These results support the idea that deep hydrothermal circulation in a warm core drives hotspots in the H2O mantle, possibly causing large tidal dissipation and internal melting.

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Transmission electron microscopy is one of the essential methods to investigate planetary materials. In this talk, I would like to present TEMs and sample preparation methods that have been used in the planetary materials science and some examples of studies, in which TEM played an important role to accomplish. I would also discuss the specification of a next-generation TEM that is suitable for the planetary materials science in the 2020s.

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Non-destructive analysis using sybchrotron radiation is definitively important for examining extraterrestrial samples particularly precious samples recovered by sample return missions. In this paper, current situations of the analytical methods and results and future objectives are presented.

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The Hayabusa 2 mission, an asteroid exploration rendezvousing at a C-type near-Earth asteroid 1999 JU3, dropping off an explosively formed impactor colliding the surface to excavate a crater, and retrieving samples of the surface to the earth, is now developing the spacecraft and payload instruments aiming at a proposed launch in December 2014. I will discuss scientific strategy according to characterization of surface condition of the asteroid, analyses of retrieved samples, modeling of the origin and evolution of C-type asteroids.

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Radioactive iodines are the most important radionuclides released from the Fukushima No. 1 nuclear power plant accident. However, it is difficult to measure ¹³¹I in terrestrial environment at present, because ¹³¹I has a short half life time of about 8 days. We have measured ¹²⁹I concentrations in the surface soil at the eastern area of the Fukushima Prefecture. ¹²⁹I/¹²⁷I ratios were measured by accelerator mass spectrometry (AMS) at the MALT, The University of Tokyo. After the accident, average isotopic ratio of ¹²⁹I/¹³¹I is estimated to 25.6 ± 5.8 on the 11th of March 2011. It is expected to estimate ¹³¹I precipitation from ¹²⁹I in the surface soil. In this presentation, we will report the distribution of ¹²⁹I in terrestrial environment and trial reconstruction of ¹³¹I precipitation by ¹²⁹I.

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In order to improve our understanding of the temporal and spatial distributions of transport and depositions of the radionuclides due to the Fukushima accident, not only observational but also simulation model studies have been conducted at the Meteorological Research Institute, Japan. Observations include HV aerosol sampling, fallout sampling and β and ? radionuclides analyses. IP photos were obtained from HV filters sampled during the course of the accident and the filters were subjected for the analysis of so-called hot particles to know about the physic-chemical states of the radioactive aerosols. Model studies have employed global and regional atmospheric transport models. For the global transport the MASINGAR model, with horizontal model grid of about 0.56?SUP?o?/SUP? and 40 vertical layers (from surface to 0.4 hPa), was used. The horizontal wind components were nudged by global analysis of Japan Meteorological Agency dataset. A regional transport model MRI-PM/r has been developed. This model classifies the aerosol particles into 6 categories, and considers condensation, evaporation, cohesion, activation of cloud condensation nuclei and ice nuclei, dissolution, collision (washout), cloud microphysical processes (conversion processes among rainout, cloud water, ice clouds, raindrops, snow, hail) and dry deposition. Emission estimates by inverse modeling approach and advanced approach of ensemble simulation of atmospheric dispersion of radionuclides during the accident have been also performed.

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There is a general consensus that the retention of RCs is controlled by the micaceous clays in soil such as illite, and selectively associates with the frayed-edge-site (FES). Radiocesium interception potential (RIP) is one of intrinsic parameters of soil in terms of their selective adsorption to RCs. In this study, eight soil and five clay mineral samples were selected to characterize their RIP, cation exchange capacity(CEC), total organic carbon content (TOC), and adsorption species by extended X-ray absorption fine structure (EXAFS) spectroscopy. Cs adsorption followed two different linear relationships between RIP, CEC, and total adsorption concentration (QT) of Cs in soil: (1) at trace concentration of Cs, [FES]/QT vs. RIP where [FES] is the capacity of FES; (2) at high concentration of Cs, [FES]/QT vs. RIP/CEC. It means that the contribution to Cs adsorption from FES have a positive linear correlation with RIP whenever it is trace or high Cs concentration.A linear correlation of RIP/CEC was observed with the ratio of coordination number (CN) of IS and OS complexes, i.e., CNis/(CNis+CNos) suggesting that CNis/(CNis+CNos) was very sensitive to the adsorption species of Cs in soil with various RIP and CEC (Fig. 1). Based on our findings, EXAFS approach can be directly employed to evaluate RCs mobility or transportation in environment combining RIP and CEC even high Cs concentration used in EXAFS sample preparation.

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