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Polymerization reaction of amino acid is an essential process for chemical evolution to life. Although it is known that solution pH significantly influence the rate of the polymerization reactions, the quantitative effects of pH have not yet investigated. In this study, the effects of pH on the rate of polymerization of Gly was quantitatively evaluated. 8-10ml of 100mM Gly solutions, having pH from 7 to 10, were poured into Teflon bottles and heated at 140 and 160°C from 1 to 14 days. After the heating procedure, the concentrations of Gly, GlyGly, DKP were measured by HPLC.It revealed that DKP is firstly composed from Gly, and then GlyGly was composed from DKP. At higher pH, the first order reaction rate constant of GlyGly formation becomes higher.

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Determination of the isotopic composition of chlorine has been carried by gas mass spectrometry and positive thermal ionization mass spectrometry. We developed negative TIMS using total evaporation method for the isotopic analysis in small rock samples.

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The study was conducted to determine the base metal pollution level in water of Nomi River, Tokyo, Japan. Nineteen water samples from different locations were collected from the whole river. Major anions and base metal concentration in water were determined by ion chromatography and inductively coupled plasma mass spectrophotometry (ICP-MS), respectively. The pH of water ranged from 6.6 to 7.57, electrical conductivity (EC) from 1.76 to 2.02 S m-1, dissolve oxygen (DO) from 11.39 to 15.91 mg L-1 and oxidation reduction potential (ORP) from 249 to 361 mV at different sampling sites. Among the major anions Cl-, Br-, NO3-, PO4−3, and SO4-2 concentration (ranged 7763 to 16010.48 ppm, 18.58 to 35.28 ppm, 19.79 to 28.89 ppm, 0.579 to 1.17 ppm and 754.07 to 1525.76 ppm, respectively) in waters varied significantly from one site to another but F- concentration didn't vary significantly. Final assessment of base metal pollution in water of Nomi River will be made from the study results.

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We report on our hypervelocity capture experiments for sample return missions using silica aerogels as capture media. Since aerogels are excellent thermal insulator, there is a possibility that samples might be thermally altered upon capturing. Thus empirical simulation in the lab is essential for rigorous examination of the captured samples. We fired hydrated phyllosilicate mineral particles which were susceptible to heat into aerogel by using two-stage light gas guns. After extraction from aerogel, several kinds of analyses were given to the samples to evaluate their alteration. We introduce results of our previous studies as well as those of preliminary experiments for TANPOPO mission.

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The Stardust spacecraft collected samples of dust from the coma of Comet 81P/Wild 2 in January 2004 and returned them to Earth in January 2006. The samples consist of a very heterogeneous mix of mineral and organic components that show the comet had a complex formation history. In my talk I will provide a brief overview of the Stardust mission and will discuss what it has taught us about the nature of comets and the origin of the Solar System. I will also discuss organics found in the samples since cometary organics may have played a role in the origin of life on Earth.

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This talk will highlight the achievements obtained from the Scanning Transmission X ray Microscopy (STXM)-based Carbon-, Nitrogen, Oxygen- X ray Near Edge Spectroscopic studies (C-, N-, O-XANES) of meteoritic organics and the returned Comet 81P/Wild 2 particles, and will appeal that the STXM-XANES enables (1) quantification of different functional groups, (2) evaluation of maximum temperature of metamorphism via 1s -> σ* exciton, and (3) distinction of structural diversity and hetetogeneity via energy shifts of the extraterrestrial organics. Finally the talk will emphasize that the STXM-XANES maximize these technique's features to the future returned microsamples, regardless of types of the samples, e.g., asteroid types.

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Cosmic dusts and carbonaceous chondrites are expected to have delivered life's raw materials to the early earth. Because these cosmic organics are very small, their in-situ characterization needs new generation of micro-spectroscopy. The development of infrared (IR) and Raman microscopic imaging spectroscopy enables rapid screening of the presence of organics in cosmic materials. We have been developing near-field infrared spectroscopy beyond the diffraction limit. These new micro-spectroscopic methods will enable measurements of small organic materials contained in cosmic materials returned from the space.

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We will present an outline of results expected from noble gas analyses on small extraterrestrial samples obtained by sample return missions. Methods of extremely small amounts of noble gases, detection limits with our noble gas mass spectrometers, and treatment of small samples will be presented.

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It has been shown that the compound-specific amino acid analysis of nitrogen isotopic values in biological samples is quite useful for reconstructing food-web structures in aquatic ecosystems. However, very little research has been applied to archaeological and terrestrial ecosystems because there is not yet enough knowledge regarding terrestrial ecological settings. On the other hand, the biological proteins in excavated bones are generally stable over long periods with respect to their chemical structure so that application to paleoecosystems using amino acid analysis may be possible. In this study, we apply this method to human and animal remains of deer, fur seal and oyster in order to evaluate the validity of the method. We sampled human bone recovered from the Kitakogane site from the late Jomon period (ca. 5200-5700 BP) in Hokkaido Japan who relied on terrestrial and marine mammals for their subsistence. Moreover, we evaluated the dietary habits of humans quantitatively by measuring the nitrogen isotopic values of specific amino acids.

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To elucidate the chemical composition of dissolved organic matter (DOM) in the Lake Baikal, we applied high resolution fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) to the lake water and inflowing river water samples.From the FT-ICR mass analysis,we found riverine organic molecules survived in L. Baikal deep water.

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The increase in carbon dioxide in the atmosphere will result in acidification in the ocean. Lagoonal water in the coral reefs is acidified due to calcification. The residence time of lagoonal water is 2-4 weeks. Therefore calcification and acidification affected by the increase of carbon dioxide in the atmosphere will modify the ecosystem especially in lagoon of the coral reefs,

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