Development of the research method for earth\u27s environmental fate byultra-trace radionuclide analysis using Accelerator Mass Spectrometry

科学研究費助成事業(科学研究費補助金)研究成果報告書：基盤研究(B)2009-2011課題番号：２１３１０００

Annual Report April 1, 2017 - March 31, 2018

1. ACCELERATOR AND RELATED FACILITIES1.1 Accelerator operation 20171.2 Measurement of the polarization of the polarized proton beam via the p-4He elasticscattering reaction1.3 Charge state distribution of ions accelerated by the 6MV tandem accelerator at UTTAC2. NUCLEAR AND ATOMIC PHYSICS2.1 Production of polarized unstable nuclei by using polarized proton beams2.2 Development of a position-sensitive detector using scintillating fibers2.3 Measurements for nitric acid produced by proton beam irradiation in a humidified air3. ACCELERATOR MASS SPECTROMETRY3.1 Operational status of the Tsukuba 6 MV multi-nuclide AMS system in fiscal 20173.2 Temporal variation of 36Cl in monthly precipitation at Tsukuba before and after theFDNPP accident3.3 36Cl record in the Antarctic ice core around the cosmic-ray event of 5480 BC studiedwith 36Cl AMS3.4 Depth profile of 36Cl in the soil at Fukushima after the Fukushima Daiichi Nuclear Power Plant accident3.5 Anthropogenic iodine-129 in the Japan Sea Bottom Water in 20173.6 Development of the prompt and sensitive determination method for strontium-90 with accelerator mass spectrometry3.7 Trial of determination of 41Ca in stony meteorites by accelerator mass spectrometry4. BEAM AND ISOTOPE APPLICATIONS4.1 Carrier trapping by vacancy-type defects in Mg-implanted GaN studied usingmonoenergetic positron beams4.2 Two-dimensional mapping of hydrogen and other elements with microbeam-basedtransmission ERDA and PIXE4.3 Production of 16 channel preamplifier module and development of high-sensitivityHERDA equipped with strip SSD4.4 Location of hydrogen in Mg/H-coimplanted GaN by RBS/ERDA and channeling NRA4.5 Present status of TOF-E telescope ERDA system development4.6 Experimental verification of a gain reduction model for the space charge effect in awire chamber4.7 Quantitative micro-PIXE analyses of trace elements in sphalerite from hydrothermallyaltered sediments4.8 Preliminary report on micro-PIXE analysis of trace Ni in single fluid inclusions from amiarolitic quartz at Tsushima granite4.9 Physico-chemical properties of active layers controlling the boric acid rejection bypolyamide composite reverse osmosis and nanofiltration membranes4.10 Thermoelectric SiGe film synthesized on a flexible plastic substrate4.11 Development of T-ERDA method for sensitive hydrogen-profiling4.12 Epitaxial strain-induced enhancement of low-temperature topotactic hydrogen substitution reaction of SrTiO34.13 Room and helium temperature Mossbauer experiments on Co-Ni ferrites toassess effect of synthesis method on magnetic properties4.14 Mossbauer spectroscopy study of spinel structured MnxFe2O4-δ particles underexternal magnetic field4.15 Magnetic properties of individual magnetite nanoparticles5. BEAM IRRADIATION EFFECT5.1 Construction of efficient radiation experiment system5.2 Comparison of LET versus SEU cross section curves for irradiation withenergetic ions and with pulsed laser6. LIST OF PUBLICATIONS AND PRESENTATIONS6.1 Journals6.2 Reviews and books6.3 Poster or oral presentations at academic meetings6.4 UTTAC seminars7. THESES8. LIST OF PERSONNE

Annual Report April 1, 2011 - March 31, 2012

1. ACCELERATOR AND EXPERIMENTAL FACILITIES1.1 Accelerator operation (2011)1.2 Post-quake reconstruction project of the Tandem Accelerator Facility at the University of Tsukuba1.3 Development of rotating magnetic field applying system for β-NMR method2. NUCLEAR PHYSICS2.1 Measurement of the astrophysical S-factor for the reaction 7Li(3He, p)9Be at 3MeV2.2 The study of nucleosyntesis by means of scandium-45 + p reaction3. MATERIAL AND CLUSTER SCIENCE3.1 Hydrogen uptake process in a-C:H film growth studied by RBS-ERDA with hydrogen isotope3.2 Droplet formation in N2/H2O/SO2 by corona discharge3.3 Measurement of secondary electron yields with a micro-channel plate or the study of cluster effects3.4 Investigation of layer thicknesses in CaF2/Fe3Si heterostructures grown on Si(111) substrates by molecular beam epitaxy3.5 Conversion electron M?ssbauer spectroscopy (CEMS) study of an iron oxide thin film fabricated by reactive sputtering3.6 M?ssbauer analysis of Mg-containing Fe3O4 nanoparticles for magnetic hyperthermia4. INTERDISCIPLINARY RESEARCH4.1 Direct characterization of hydrogen content in MLCC employing elastic recoil coincidence spectroscopy5. LIST OF PUBLICATIONS5.1 Journals5.2 International conferences6. LIST OF PUBLICATIONS7. THESES8. SEMINARS9. SYMPOSIA10. LIST OF PERSONE

Willingness to pay for school counseling services in Japan: A contingent valuation study

Increases in mental health problems within Japan\u27s school population have led the Japanese government to initiate school counselling services. However, the development of counselling services is hindered by the lack of public appreciation for the magnitude of mental health problems and the lack of clarity regarding the economic benefits of such counselling services. The aim of this study was to evaluate perceptions of the economic value of school counselling services. An internet-based questionnaire survey using a contingent valuation method was conducted (n=600). Data on age, sex, marital status, family structure, job, annual household income, present/lifetime experience in using counselling services, and familiarity with school counselling services were compiled. Main outcome measure was willingness to pay for school counselling services. Study participants indicated a median willingness to pay JPY 1,332 (USD 13.32) per year for counselling services. The logistic regression analysis showed that the present use of counselling services and having children were significantly associated with WTP, while the other measured variables were not. The present study clarifies the public perception of the monetary value of school counselling services, and thus provides useful information to policymakers and taxpayers

A copper-benzotriazole based coordination polymer catalyzes the efficient one-pot synthesis of (N'-substituted)-hydrazo-4-aryl-1,4-dihydropyridines from azines

A series of new (N’-substituted)-hydrazo-4-aryl-1,4 dihydropyridines were successfully synthesized via a facile one pot catalytic pathway utilizing azines and propiolate esters as starting materials and 1D Cu benzotriazoles based coordination polymer as catalyst. In the absence of catalyst, the corresponding 5-substituted 4,5-dihydro pyrazoles were formed in moderate to high yields. Fine-tuning the catalysts allowed us to gain more insights regarding the plausible reaction mechanism

Estimation of Dietary Intake of Radionuclides and Effectiveness of Regulation after the Fukushima Accident and in Virtual Nuclear Power Plant Accident Scenarios

Evaluation of radiation exposure from diet is necessary under the assumption of a virtual accident as a part of emergency preparedness. Here, we developed a model with complete consideration of the regional food trade using deposition data simulated by a transport model, and estimated the dietary intake of radionuclides and the effectiveness of regulation (e.g., restrictions on the distribution of foods) after the Fukushima accident and in virtual accident scenarios. We also evaluated the dilution factors (i.e., ratios of contaminated foods to consumed foods) and cost-effectiveness of regulation as basic information for setting regulatory values. The doses estimated under actual emission conditions were generally consistent with those observed in food-duplicate and market-basket surveys within a factor of three. Regulation of restricted food distribution resulted in reductions in the doses of 54–65% in the nearest large city to the nuclear power plant. The dilution factors under actual emission conditions were 4.4% for radioiodine and 2.7% for radiocesium, which are ~20 times lower than those used in the Japanese provisional regulation values after the Fukushima accident. Strict regulation worsened the cost-effectiveness for both radionuclides. This study highlights the significance and utility of the developed model for a risk analysis of emergency preparedness and regulation

A study of the Suess effect using a raised peat bog as historical archive

The radiocarbon content in a peat core from Gävle, Sweden, 61.0 oN, 17.0 oE, has been studied. This is a raised peat bog which only receives material from atmospheric deposition. There has been an increased use of fossil fuels by industries and also locally by transports and heating of domestic buildings. There has been fallout of 14C from nuclear tests during the 1950ies and 1960ies and also from the Chernobyl accident in 1986. There is also emission of 14C from nuclear facilities. The 14C/12C ratio from the Chernobyl accident is unclear since it was a graphite moderated reactor and the graphite was burning. The core was sampled in 2008 and was previously dated using the 210Pb method, giving a growth rate of 0.15 mm/yr. The top 21 cm have been analyzed to obtain radiocarbon content by Accelerator Mass Spectrometry (AMS) at the Centro Nacional de Aceleradores (CNA), Seville Spain. Using 0.5 cm samples, information about the last 140 years could be obtained with resolution better than 4 years. Results show a clear depletion of F14C levels in the area, the so called SUESS effect with maximum levels of only F14C=1.2333±0.0043, and the absence of a clear nuclear tests peak

Annual Report April 1, 2009 - March 31, 2010

1. ACCELERATOR AND EXPERIMENTAL FACILITIES1.1 Accelerator operation (2009)1.2 Status of the Tsukuba AMS system (2009)1.3 The developments of detectors of the particle identification for RI beam experiment1.4 Development of active target with gas electron multiplier2. NUCLEAR PHYSICS2.1 Study of the structure of 30S by in-beam gamma ray spectroscopy and the 29P(p,g)30S reaction rate in classical novae2.2 Measurement of nuclear magnetic moment of unstable nucleus 40Sc. II2.3 Measurement of nuclear magnetic moment of unstable nucleus 30P2.4 Study of nuclear synthesis of 26Al by gamma ray spectroscopy III3. MATERIALS AND CLUSTER SCIENCE3.1 Electron emission from surfaces bombarded by MeV atom clusters3.2 X-ray absorption spectroscopy of Mg-Ni and Mg-Ti hydride3.3 The vicinage effect on energy loss of C+2 in a thin carbon foil3.4 Study on nitrogen diffusion in e-Fe2?3N submicron particles4. ACCELERATOR MASS SPECTROMETRY4.1 Fluctuations in cosmic ray flux around 11 kyr BP based on cosmogenic 36Cl from the Dome Fuji ice core4.2 Distribution of 36Cl in the Yoro River basin and its relation to regional groundwater flow system4.3 Measurement of 36Cl in soil : Study of extraction methods according to reservoirs4.4 Chlorine-36 produced in muon irradiation4.5 Production rates of 36Cl for target elements in chondritic meteorites (II)5. INTERDISCIPLINARY RESEARCH5.1 Trace-element analysis of fluid inclusions in the Tsushima granite, Japan5.2 Nanopore fabrication by irradiating accelerated ions for high-sensitivity waveguide-mode sensors6. LIST OF PUBLICATIONS6.1 Journals6.2 International conferences7. THESES8. SEMINARS9. SYMPOSIA10. LIST OF PERSONE

Annual Report April 1, 2014 - March 31, 2015

1. ACCELERATOR AND RELATED FACILITIES1.1 Accelerator operation 20141.2 Performance prediction of the new Tsukuba AMS system1.3 Reconstruction of the Lamb-shift polarized ion source2. NUCLEAR PHYSICS2.1 Measurements of nuclear moments for unstable nuclei at RCNP2.2 Beam irradiation test of Havar foil and Pt target for KISS experiment2.3 Production of unstable nuclei via resonant proton-capture reactions3. ACCELERATOR MASS SPECTROMETRY3.1 Performance test of automated sample preparation system for 14C-AMS using IAEAreference materials3.2 Study on the migration behavior of Fukushima accident-derived iodine-129 from land areato the marine environment3.3 Changes in 129I / 127I ratio of crater lake and volcanic activity at Zao volcano3.4 Technological development for Strontium-90 determination using AMS3.5 Successive searches of iodine-129 contamination in the chemical sample preparationrooms for AMS4. MATERIALS ANALYSIS BY ION BEAMS OR RADIO ISOTOPES4.1 Micro-PIXE analyses of single fluid inclusions in quartz from Tanzawa granite, Japan4.2 Coincidence detection system of ion and secondary electron in HERDA4.3 Straggling effect in channeling on Si(100) with metal thin films4.4 M?ssbauer spectroscopy of ferromagnetic Fe3O4 nanoparticles developed for magnetichyperthermia4.5 Conversion electron M?ssbauer spectroscopy (CEMS) of cobalt ferrite thin films4.6 Magnetization control of Co ferrite thin films by Kr ion implantation4.7 Oxygen and sulfur isotopic analysis of ion-induced sulfate production reaction initiatedvia proton beam5. LIST OF PUBLICATIONS5.1 Journals5.2 International conferences6. THESES7. SYMPOSIAThe 15th Japanese national workshop on surface and interface ion beam analysisThe 17th Japanese Symposium on Accelerator Mass Spectrometry8. LIST OF PERSONNE

Local variance of atmospheric 14C concentrations around Fukushima Dai-ichi Nuclear Power Plant from 2010 to 2012

Radiocarbon (14C) has been measured in single tree ring samples collected from the southwest of the Fukushima Dai-ichi Nuclear Power Plant. Our data indicate south-westwards dispersion of radiocarbon and the highest 14C activity observed so far in the local environment during the 2011 accident. The abnormally high 14C activity in the late wood of 2011 ring may imply an unknown source of radiocarbon nearby after the accident. The influence of 14C shrank from 30 km during normal reactor operation to 14 km for the accident in the northwest of FDNPP, but remains unclear in the southwest