記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Several kinetic models have been proposed to evaluate the aqueous dissolution/ alteration rate of nuclear waste glass for long-term. However, reaction processes controlling the long-term rate are much more subjected to controversy. Temperature dependence of the long-term alteration rate is an essential issue to understand the rate controlling processes. In the present study, the static aqueous alteration tests were performed with a Japanese simulated waste glass P0798 as a function of temperature from 60°C to120°C, and the temperature dependence of the long-term alteration rate was evaluated to understand the rate controlling processes. The tests were performed in 0.001M NaOH solution to maintain a constant solution pH of around 10 during the test period and to provide smectite forming conditions where smectite forms as the major secondary phase without zeolite formation. From the test results on dissolution of boron, the alteration rate at each temperature was analyzed by use of a water-diffusion model. The water-diffusion model used is based on a simple assumption; the glass alteration is controlled by water diffusion with ion-exchange between water (hydronium ion: H3O+) and soluble elements (B, Na, Li, etc) at the glass surface layer with the apparent diffusion coefficient Di. A good agreement was observed between the model analysis and the test results, and the value of Di was evaluated to be 1.2 x 10-22 m2/s at 60°C to 1.8 x 10-21 m2/s at 120°C. The Arrhenius plot of Di showed a good linearity to give the activation energy of 49 kJ/mol, which value is close to that for the residual dissolution rate of French waste glass (53 kJ/mol) by Gin [1], and is very close to that for ion-exchange in sodium aluminosilicate glass (49 kJ/mol) by McGrail [2]. These results suggest that water diffusion with ion-exchange can be the dominant process controlling the alteration rate under smectite forming conditions. At elevated temperatures (100°C and 120°C), however, the model-predicted boron releases deviated from the experimental data at the later stage beyond 50-80 days, which suggests that the alteration layer developing at the glass surface may evolve to be protective against the water diffusion to depress the alteration rate as the alteration proceeds.

出版者・発行元：Materials Letters  

The aqueous dissolution rate was measured precisely for two kinds of reference nuclear waste glasses, ISG and P0798, as a function of aqueous Si concentration and pH of a solution by using the micro-channel flow-through test method with Si isotopes. The glass dissolution rate determined from the Si dissolution rate decreased with increasing aqueous Si concentration at pH 9. In contrast, the dissolution rate at pH 4 was not affected by the Si concentration or increased slightly with an increase in the Si concentration. Therefore, the glass dissolution mechanism with the altered surface properties depended sensitively on pH, causing large changes in the glass dissolution kinetics.

DOI： 10.1016/j.matlet.2024.137797

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出版者・発行元：Journal of Physical Chemistry C  

A neural network potential (NNP) for molecular dynamics simulation (MD) of multicomponent oxide glasses was developed with a particular focus on structural reproducibility. The NNP was constructed through pretraining using a density functional theory (DFT) data set provided by the Open Catalysis project and fine-tuning based on a data set of nine-component glasses. Thorough validation was performed by comparing a glass structure derived using neural network molecular dynamics simulation (NNMD) and the NNP developed here with previous experimental and DFT-MD data. The accuracy of the NNMD was investigated in terms of the local structure of the glass, in comparison with a glass derived from MD with conventional potentials. The composition dependence of the local structure in Na<inf>2</inf>O-SiO<inf>2</inf> and Na<inf>2</inf>O-B<inf>2</inf>O<inf>3</inf> glass systems was well-reproduced for the NNMD-derived glass. The ability to reproduce the glass structure was demonstrated in the four-coordinated boron population, by formation of superstructures in alkali borate glasses, and by the Al local structure in a novel Al-rich binary aluminoborosilicate glass. The importance of pretraining was investigated by comparing NNMD results obtained using the NNP developed with and without pretraining. Although better metric scores were obtained for the NNP without pretraining, the resulting structure was not realistic. This is an important lesson, showing that the metric score alone is inadequate to determine the accuracy of an NNP for glasses. Finally, the developed NNMD was used to model a reference nuclear waste glass (60.1SiO<inf>2</inf>-3.84Al<inf>2</inf>O<inf>3</inf>-15.97B<inf>2</inf>O<inf>3</inf>-12.65Na<inf>2</inf>O-2.87CaO-2.86MgO-1.72ZrO<inf>2</inf>), and the charge compensation mechanism of the cations was investigated.

DOI： 10.1021/acs.jpcc.4c04604

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出版者・発行元：Journal of the American Ceramic Society  

Understanding mass transport in the alteration layers of glass surfaces is a crucial component of the safety assessment of nuclear waste glass. In this work, we model such an alteration layer as a silicate gel with water through a molecular dynamics (MD) simulation with a reactive force field. Gels with various water contents (WCs) ranging from 5.1 to (Formula presented.) are produced via high-temperature annealing with water and silica. It is found that an increase in the water content destroys the polymerized structure of the silicate network and promotes the formation of silanol groups. The pore size and water connectivity formed by the silicate networks are investigated for the modeled gels. Gel with a WC of (Formula presented.) is composed of isolated water in the pores; in contrast, pores filled with interconnected water are formed in gel with a WC of (Formula presented.). The water diffusivity in the modeled gel is calculated using the mean-squared displacement at various temperatures. An attempt is made to formulate a linear relationship between the water diffusivity and porosity derived from the MD simulation. The porosity is calculated using a probe atom with a radius, which was optimized from a linear relationship between the water diffusivity and porosity. This approach successfully explains the water diffusivity in terms of the porosity. Random walk (RW) simulations for the structures derived from the MD simulations are performed to determine the geometrical effects of the pores. The diffusivity obtained from RW simulation is compared with the results of the MD simulations, which include chemical interactions such as the formation and breakage of hydrogen bonds. This comparison highlights how geometrical effects and chemical interactions contribute to water diffusivity depending on the WC.

DOI： 10.1111/jace.19935

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出版者・発行元：Journal of Nuclear Science and Technology  

The flexible waste management (FWM) system has been proposed in order to apply the partitioning and transmutation (P&T) technology for minor actinides (MA) to the current high-level liquid waste (HLLW). This system consists of HLLW calcination to produce easy-to-dissolve granule; its temporary storage is required until the P&T technology deployment and re-dissolution of the granule to remove MA from HLLW after the future P&T technology deployment. The fundamental experiments were conducted to clarify the applicability of FWM system to the current HLLW, and the results indicate the technological validity of the system. The evaluations were carried out for the reduction of storage amount, potential radiotoxicity, and repository area of high-level waste.

DOI： 10.1080/00223131.2023.2226673

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

Diffusion couples made of dense polycrystalline U1− αPuα− βAmβO2±γ/U1− yPuy− zAmzO2±x oxides were annealed in various thermodynamic conditions (temperature, oxygen partial pressure), and for different durations. The associated actinide redistribution was quantified using Electron Probe Micro-Analysis (EPMA). Average diffusion profiles were obtained from elemental U, Pu, and Am X-ray maps and the resulting interdiffusion coefficients were calculated, then analyzed at the light of our model of point defect chemistry.

掲載種別：研究論文（学術雑誌）   出版者・発行元：Journal of Nuclear Materials  

Diffusion couples made of dense polycrystalline U1−αPuα−βAmβO2±γ/U1−yPuy−zAmzO2±x oxides were annealed in various thermodynamic conditions (temperature, oxygen partial pressure), and for different durations. The associated actinide redistribution was quantified using Electron Probe Micro-Analysis (EPMA). Average diffusion profiles were obtained from elemental U, Pu, and Am X-ray maps and the resulting interdiffusion coefficients were calculated, then analyzed at the light of our model of point defect chemistry.

DOI： 10.1016/j.jnucmat.2023.154786

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記述言語：英語   出版者・発行元：一般社団法人 日本機械学会  

<p>Leaching tests of simulated fuel debris (CeO₂, (Ce, Fe)O₂, (U, Zr)O₂ and (U, Zr, Ca)O₂) were conducted by using the microchannel flow-through method. The pellet-shaped specimens were fixed with epoxy resin and polished. A Teflon sheet 0.16 mm thick with a slit 2 mm wide and 20 mm long was attached to the polished surface of the specimen, then various solutions, leachant, were passed through the slit at 6 μL/min as a microchannel. Samples of solutions, leachate, were collected every 3 hours, diluted with 2% nitric acid, and analyzed for Ce or U using ICP-MS to determine the dissolution rate.</p><p>The (U, Zr)O₂ specimens separated into two phases when Zr was above 25%, while the (U,Zr,Ca)O₂) specimen was a single-phase up to about 50% Zr, due to the presence of a few % of Ca. The porosity of the phase-separated specimens was more than 10%, whereas the porosity of the single-phase specimens was only a few percent.</p><p>Single-phase specimens show smaller dissolution rates than multi-phase specimens. This is due to the formation of cracks and voids in the specimen by density change during phase transformation, which increases the contact area. The dissolution rate of UO₂ is larger than of CeO₂ even for the same single-phase specimen and porosity. This could be because uranium is in a highly soluble oxidation state, while cerium remains in a less soluble tetravalent state. In the case of uranium-based single-phase specimens, the dissolution rate tended to be lower with higher Zr composition. When the leachant was 1M NaCl solution, the dissolution rate of CeO₂ was slightly larger than that for pure water. Conversely, the normalized dissolution rate of uranium simulated debris was smaller for 1M NaCl solution than for pure water. This might be because uranium reacts with the NaCl component to form a protective film. SEM observation of the surface of the leached portion of the specimen before and after the leaching test showed elution of fine particles less than 1 μm in diameter and elution from the edge of the specimen. No significant dissolution of individual phases was observed in multi-phase specimens. Although the actual fuel debris initially contacted with seawater and then with freshwater, it is highly likely that particles of a few micrometers in diameter were dissolved. However, fuel debris larger than a few mm can be considered to dissolve only a part of the surface.</p>

DOI： 10.1299/jsmefdr.2024.0_1029

CiNii Research

掲載種別：研究論文（学術雑誌）   出版者・発行元：MRS Advances  

The flow-through method and the profile method are used for determining diffusion coefficients. If the diffusion coefficient is small, only the profile method is suitable. In the profile method, the apparent diffusion coefficient can be obtained by setting an appropriate diffusion period. However, if an experiment is conducted with a longer diffusion period, the apparent diffusion coefficient may appear small. This phenomenon is observed in the diffusion of neptunium in compacted bentonite in an atmosphere with high carbonate ion concentrations. One interpretation is that the neptunyl carbonate complex can only pass through a limited size of pores in the compacted bentonite because the complex is so large and negatively charged. In this work, a long-term diffusion experiment was conducted over 3 years, and the diffusion profile of neptunium in compacted bentonite was exponential owing to filtration and did not change over time. Exponential profiles were also observed for large oxoanions, such as molybdate ions, and for plutonium in a 20-year iron corrosion environment. Graphical abstract: [Figure not available: see fulltext.].

DOI： 10.1557/s43580-023-00501-9

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その他リンク： https://link.springer.com/article/10.1557/s43580-023-00501-9/fulltext.html

記述言語：英語   掲載種別：研究論文（学術雑誌）  

出版者・発行元：Journal of Physical Chemistry C  

Altered glasses produced during the aqueous dissolution of silicate and borosilicate glasses are among the most complex structures to understand at the atomic level due to their amorphous nature, random porosity, and various levels of hydration. In this study, we gained insights into the complex atomic structures of altered aluminoborosilicate glasses by combining a range of experimental and computational approaches. The altered glasses were prepared by the dissolution of three glasses with varying levels of alumina in an acid for 7 days. A comprehensive set of experimental [elemental analysis, high-energy X-ray diffraction, ²⁹Si and ²⁷Al solid-state nuclear magnetic resonance (NMR), and O 1s X-ray photoelectron spectroscopy (XPS)] and modeling (molecular dynamics (MD) simulations using nonreactive and reactive force fields) approaches were used to study the atomic structures of these altered glasses. Elemental analysis showed that most of the B in the pristine glasses was leached into the solution and was not contained in the altered glass. The ²⁹Si and ²⁷Al solid-state NMR spectra revealed that the altered glasses have more polymerized silicate networks as compared to those in the pristine glasses due to the reformation of linkages among Si and Al oxygen polyhedral in the altered glasses. The bridging and nonbridging (or hydroxyl O) atoms in the altered glasses were also quantified from their O 1s XPS spectra. Atomic structure models of the altered glasses were constructed using MD simulations using the reactive force field based on the compositional information obtained from experiments. Various pore structures were generated using the charge-scaling (CS) method using different initial densities and CS temperatures; the best CS parameters of each altered glass were then determined by comparing with the experimental structure factors obtained from high-energy X-ray diffraction. Pore and atomic structures and vibrational properties around these pore surfaces were analyzed. These results from this comprehensive study thus provide a realistic insight into the pore morphology, atomic structure, and vibrational properties of altered glasses.

DOI： 10.1021/acs.jpcc.1c10463

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記述言語：英語   掲載種別：研究論文（学術雑誌）  

掲載種別：研究論文（学術雑誌）   出版者・発行元：MRS Advances  

The diffusion behavior of neptunium (Np) in compacted bentonite with bicarbonate was investigated at various NaHCO3 concentrations. Typical Japanese purified Na-bentonite, Kunipia-F, which contains approximately 95 wt % montmorillonite, was used. The Na-bentonite was compacted with a jig into cylindrical pellets 10 mm in diameter and 10 mm high with dry densities of 0.7 to 1.4 Mg/m3. Each pellet was inserted into an acrylic resin column and saturated with carbonated water containing 0.25 to 1.0 M NaHCO3 for more than 1 month. The bottom interface of the compacted bentonite saturated with carbonated water was spiked with 5 µL of tracer solution containing 10 ppb of Np in 0.1 M HNO3, and the diffusion periods were in the range of 2.7 years. After the diffusion period, the bentonite specimen was pushed out of the column and cut into 0.3- to 1.0-mm-thick slices. Each slice was submerged in 1 N HNO3 to extract the tracer ion and the liquid phase was separated by centrifugation. The supernatant was analyzed for Np by inductively coupled plasma-tandem mass spectrometry. The Np concentration profile increased over time and reached the final profile in 2 years. The final profile showed logarithmic decay with a decay or filtration coefficient of 3.2 ± 0.1 mm−1. This final profile indicated that Np could diffuse but would be filtered by the bentonite medium. Np may exist as carbonate complexes, which could be larger than the pores constituting the diffusion path.

DOI： 10.1557/s43580-022-00210-9

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その他リンク： https://link.springer.com/article/10.1557/s43580-022-00210-9/fulltext.html

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： DOI: 10.1557/adv.2020.55

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： DOI: 10.1299/jsmeicone.2019.27.2095

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： DOI: 10.1299/jsmeicone.2019.27.1927

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： DOI: 10.1557/adv.2019.81

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： DOI: 10.1557/adv.2018.184

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Aqueous dissolution rate measurements of nuclear glasses are a key step in the long-term behavior study
of such waste forms. These rates are routinely normalized to the glass surface area in contact with solution,
and experiments are very often carried

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Chemical durability is not a single material property that can be uniquely measured. Instead it is the response to a host of coupled material and environmental processes whose rates are estimated by a combination of theory, experiment, and modeling. High-level nuclear waste (HLW) glass is perhaps the most studied of any material yet there remain significant technical gaps regarding their chemical durability. The phenomena affecting the long-term performance of HLW glasses in their disposal environment include surface reactions, transport properties to and from the reacting glass surface, and ion exchange between the solid glass and the surrounding solution and alteration products. The rates of these processes are strongly influenced and are coupled through the solution chemistry, which is in turn influenced by the reacting glass and also by reaction with the near-field materials and precipitation of alteration products. Therefore, those processes must be understood sufficiently well to estimate or bound the performance of HLW glass in its disposal environment over geologic time-scales. This article summarizes the current state of understanding of surface reactions, transport properties, and ion exchange along with the near-field materials and alteration products influences on solution chemistry and glass reaction rates. Also summarized are the remaining technical gaps along with recommended approaches to fill those technical gaps.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

International Simple Glass (ISG) is a six-component alumino-borosilicate glass developed as a reference benchmark glass for six nations collaborating study on high-level nuclear waste glass dissolution/corrosion mechanism. In the present study, aqueous dissolution tests were performed for the ISG by using Micro-Channel Flow-Through (MCFT) method to evaluate the initial dissolution rate of glass matrix, r0, precisely and systematically as a function of solution pH and temperature. The test results indicated that the r0 shows a “V-shaped” pH dependence with a bottom at around pH4 at each temperature. Compared to Japanese reference glass of P0798, for which the r0 showed a “U-shaped” pH dependence with a bottom at around pH6 in our previous study, the ISG shows the higher dissolution rate at basic pH, and lower dissolution rate at neutral to acidic pH. The results also indicated that the r0 increases with temperature according to an Arrhenius law, and the apparent activation energy evaluated from Arrhenius relation is 62-77 [kJ/mol] at any pH from 3 to 10, which suggests the initial dissolution of ISG proceeds controlled by a surface-reaction mechanism in this pH range.

掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

掲載種別：研究論文（学術雑誌）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

The thermal impacts of hull and end piece wastes from high-burn-up UO2 and MOX fuels on a conventional disposal system were investigated.

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

Static aqueous alteration tests were performed with a Japanese simulated HLW glass, P0798, in the presence of bentonite in order to understand the effects of bentonite on the glass alteration kinetics and on the associated Cs release. Analogous alteration tests were performed in 0.001M NaOH solution without bentonite for comparison. The results indicated that; 1) at the initial stage of alteration up to 50 days, no remarkable difference was observed in the alteration rate between both cases “with” and “without” bentonite, 2) at the later stage beyond 50 days, however, the rate in the case “with” bentonite was larger than that in the case “without” bentonite. These results on the alteration rate were analyzed by use of a water-diffusion model. In the case “without” bentonite, a good agreement was observed between the model analysis and the experimental results at the initial stage of alteration up to 50 days, however, the model analysis deviated from the experimental results at the later stage beyond 50 days. In the case “with” bentonite, on the other hand, a good agreement was observed even at the later stage to give the value of the apparent diffusion coefficient, Di of 3.5x10-21 m2/s. The comparison between both cases suggests that the alteration rate is controlled by the water diffusion in both cases “with” and “without” bentonite, however, the rate is depressed in the case “without” bentonite probably by the protective effects of the alteration layer developing at the glass surface. In the case “with” bentonite, on the other hand, the alteration layer is expected to be less protective. Cesium desorption tests performed for the altered glass and bentonite indicated that most of the cesium dissolved from the glass is retained in the secondary phase of smectite developing in the precipitated layer by sorption with ion-exchange in the case “without” bentonite. In the case “with” bentonite, however, it is likely to be sorbed at bentonite surface.

記述言語：英語   掲載種別：研究論文（学術雑誌）  

Aqueous alteration tests were performed with a Japanese simulated waste glass P0798 in alkaline solutions as a function of pH or species/concentration of alkaline metals in the solution in order to evaluate the alteration conditions determining whether smectite (2:1 clay mineral) or analcime (zeolite) forms as the major alteration-phase. XRD analysis of the alteration-phases showed that smectite forms at any pH between 9.5 and 12, and analcime forms at pH above 11, though the formation also depends on species and concentrations of alkaline metals in the solution. These results cannot agree with the thermodynamically predicted phase stability, e.g., smectite is more stable than the thermodynamic prediction shows. On the basis of the results of alteration conditions, the alteration tests were performed under smectite forming conditions, where only smectite forms or no crystalline phases form, in order to evaluate the alteration rate and the mechanism of cesium release/retention. The results showed that the glass alteration proceeds slowly in proportion to square root of time under smectite forming conditions, which indicates that the alteration rate can be controlled by a diffusion process. It was suggested that the alteration rate under smectite forming conditions is independent of the pH, alkaline metal species/ concentration in the solution and whether smectite actually forms or not. The results also indicated that most of cesium dissolved from the glass can be retained in the alteration-phases by reversible sorption onto smectite or irreversible incorporation into analcime, pollucite or solid solutions of them.

記述言語：日本語   掲載種別：研究論文（学術雑誌）  

A review is given of the performance assessment of high-level radioactive waste(HLW) glass in geological disposal in an aspect of its validity. In the last few decades much progress has been made in understanding elementary reactions of HLW glass dissolution in contact with aqueous solutions and of associated radionuclide release. On the basis of the present knowledge, a conservative assessment of the glass performance can be made in geological disposal. For confirming its validity, however, more progress is required to be made in understanding reaction mechanism of the glass dissolution for the long-term of disposal period and in evaluating effects of the specific disposal conditions on the glass dissolution for each country. In addition to sound understanding of scientific basis for the glass dissolution described above, it is also essential to develop the glass performance model taking the scientific basis into account. Progress in these fundamental studies on the glass performance is expected to contribute to a valid assessment of the total system performance of disposal, which can lead to the reasonable and economical disposal. Studies on the glass performance at the present in Japan are less advanced than those conducted widely in France and the United States. Further works are required for the valid assessment of the glass performance in Japan.

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

記述言語：英語   掲載種別：研究論文（学術雑誌）  

DOI： 10.1016/S0022-3115(01)00588-8

記述言語：英語   掲載種別：研究論文（国際会議プロシーディングス）  

開催年月日： 2023年9月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Museum Romanité, Nimes   国名：フランス共和国  

Over the last few decades, understanding the kinetics of nuclear waste glass dissolution/alteration in aqueous media has advanced through a large number of the experimental and atomistic simulation studies performed by a large number of researchers in the world, which has contributed successfully to an advance of modeling the glass dissolution/alteration for the geological disposal. For assessing the long-term glass performance in geological disposal with reliability, however, we need a greater understanding of the glass dissolution/alteration kinetics under the actual repository conditions in consideration of the potential long-term evolution of the repository conditions. The greater understanding of the dissolution/alteration kinetics is also required for parameterization of a mechanistic model used to determine the glass dissolution/alteration rate with the radionuclide release rate as a function of key environmental variables such as the solution composition, pH, Eh, temperature, and time. For the understanding of glass dissolution/alteration kinetics, we need experimental data on the glass dissolution rate measured precisely, consistently and systematically under well-constrained test conditions. Along with the data on the dissolution rate, which is usually determined from solution analysis, we also need the data on the altered glass surface properties, such as morphology of alteration layers, chemical composition, elemental depth profile, crystallinity, stability, density, porosity, permeability of water and glass constituent elements, etc., analyzed for the glass altered under well-constrained test conditions. For the last few decades, a large number of dissolution tests have been performed for the waste glasses, however, there have existed only a few data available for evaluation of the dissolution kinetics, because of difficulties in precise and systematic measurement. With respect to pH dependence of the glass dissolution rate, for example, we have only a few data available for the systematic evaluation, because the test conditions such as the solution composition, pH, and the glass surface area can change easily during the test period against the expectations as a consequence of the nature of the current standard test methods such as MCC-1 and PCT tests. Therefore, we have developed a new test method, “Micro-channel flow-through (MCFT) method”, to measure the glass dissolution rate precisely and systematically under various well-constrained test conditions, and applied it to measurement of the glass dissolution rate as a function of environmental parameters such as the solution composition, pH, temperature. The MCFT method has been applied first to measurement of the initial dissolution rate, r0, as a function of pH and temperature for an international reference glass ISG and a Japanese reference glass P0798. The r0 has been measured successfully to provide the systematic data of r0 as a function of pH, where ISG showed a “V-shaped” pH dependence with a minimum at pH4, while P0798 glass shows a “U-shaped” pH dependence with a minimum at pH6. While the systematic data of r0 as a function of temperature at each constant pH has provided the apparent activation energy, Eact, for the initial dissolution. The Eact was evaluated to be 60-70 [kJ/mol] at acidic to weakly basic pH for ISG, which suggests a surface-reaction controlled-dissolution mechanism. For P0798, the Eact was evaluated to be 60-70 [kJ/mol] at neutral to weakly basic pH as well as ISG, however, the Eact at acidic pH was evaluated to be 50 [kJ/mol], which suggests a diffusion -controlled dissolution mechanism. Currently, we have been trying to measure the glass dissolution rate as a function of solution concentration of Si by using the MCFT method and Si-isotopes. The concentration of Si dissolved in solution has been considered to be one of fundamental factors dominating the glass dissolution kinetics, and the rate equation based on the first-order dissolution rate law of pure amorphous silica has been proposed to be applied to modelling the glass dissolution/alteration as follows, r = r0 (1-[H4SiO4]/K) (eq.1) where r is the glass dissolution rate, r0 is the initial dissolution rate, [H4SiO4] is the activity of orthosilicic acid at the glass surface, and K is the equilibrium constant (which equals the activity of orthosilicic acid at saturation). We have been accumulating the data on the glass dissolution rate as a function of solution concentration of Si for ISG and P0798, and some of the interesting results will be

開催年月日： 2023年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：名古屋大学   国名：日本国  

開催年月日： 2023年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：名古屋大学   国名：日本国  

開催年月日： 2022年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：茨城大学   国名：日本国  

ガラス固化体の溶解挙動は環境条件(溶液組成, pH, 温度, 時間等)によって複雑に変化する。本研究では、ガラス試料として日本の標準模擬ガラス固化体P0798、反応溶液としてSi-29濃縮シリカ溶液を用い、マイクロチャネル流水試験を実施して、反応溶液の溶存Si濃度及びpHがガラス溶解速度に与える影響を評価した。

開催年月日： 2022年5月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Online   国名：アメリカ合衆国  

Dissolution rate of simulated nuclear waste glass ISG was measured at 70 °C by using Micro-Channel Flow-Through test method as a function of solution concentration of Si at constant pH of 4, 7 and 9, respectively. Si-29 isotope was used for preparing the reaction solution with the Si concentration from 0 to 120ppm in order to distinguish between Si dissolved from glass and Si dissolved in the original solution, and the glass dissolution rate was determined by measuring the dissolution rate of Si-28, major Si isotope (92.2%) of natural Si being consisted of ISG. The test results showed that the glass dissolution rate decreases drastically with an increase of solution concentration of Si at both pH7 and pH9, where the dependency of solution concentration of Si cannot be accounted by the ordinal first-order dissolution rate law based on SiO2dissolution. At pH4, however, the tendency of glass dissolution rate was different from that at pH7 and pH9, where the solution concentration of Si had no remarkable effects on the glass dissolution rate. These results suggested the glass dissolution kinetics change depending on solution pH sensitively.

開催年月日： 2022年3月 - 2022年6月

記述言語：日本語   会議種別：口頭発表（招待・特別）  

開催地：オンライン   国名：日本国  

開催年月日： 2021年9月 - 2021年8月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：オンライン   国名：日本国  

高レベルガラス固化体の溶解挙動はガラス組成に加え、pH、地下水組成等の環境条件によって複雑に変化する。本研究では、ガラス試料として国際標準模擬ガラス固化体(ISG)、反応溶液としてSi−29濃縮溶液を用いて、マイクロチャネル流水試験を行うことで、様々なpH条件におけるガラス溶解速度の溶存シリカ濃度依存性を測定・評価した。

開催年月日： 2021年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：オンライン   国名：日本国  

開催年月日： 2020年9月

記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2019年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：富山大学   国名：日本国  

ガラス固化体の溶解挙動はガラス組成に加え、環境条件（温度, pH, 地下水組成, 反応時間等）によって複雑に変化する。本研究では、国際標準模擬ガラス固化体(ISG)について、反応溶液にSi-29濃縮シリカ溶液を用いてマイクロチャネル流水試験を行い、ガラス溶解速度の溶存シリカ濃度依存性を測定・評価した。

開催年月日： 2019年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：富山大学   国名：日本国  

福島第一原発の汚染水処理で発生しているCs吸着ゼオライト廃棄物の合理的な処理方法として溶融ガラス固化が挙げられる。本研究ではガラス融剤の種類/添加量、溶融時間等の固化条件をパラメータとしてCs吸着ゼオライトをガラス固化し、ガラス溶融時のCs揮発挙動を速度論的に評価した。

開催年月日： 2019年4月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東京工業大学   国名：日本国  

1. 緒言 原子力発電を行うための一連のプロセス全体が「核燃料サイクル」であり，その最終段階に位置する放射性廃棄物の処理・処分のプロセスが「バックエンド」となる．ここでは，バックエンド事業の現状とその進展に必要な研究・開発の課題，更には核燃料サイクルの進展とバックエンドの役割について概説する． 2. 放射性廃棄物の種類・分類 　現在の核燃料サイクルは，燃料となるウランの採鉱に始まり，ウラン濃縮，燃料ペレット製造，原子炉での燃焼と発電を経て使用済燃料の再処理さらには原子力施設の廃止措置（解体）に至る複数のプロセスから成るが，各プロセスでは様々な放射性廃棄物が発生し，その処理と最終処分がサイクルの最終プロセス（バックエンド）となる．これらの放射性廃棄物は，放射能レベル（重量，体積当りの放射能），放射性核種の種類（α・β・γ核種および半減期），性状等によって幾つかの種類に分類される．現在の分類では「高レベル放射性廃棄物」と「低レベル放射性廃棄物」に大別され，このうち「低レベル放射性廃棄物」はさらに「超ウラン核種を含む廃棄物（TRU廃棄物）」「発電所廃棄物（放射能濃度に応じてL1, L2, L3に分類）」「ウラン廃棄物」に分類され，それぞれの特性に応じて処理・処分が行われる． 3. 高レベル放射性廃棄物の処理・処分 　高レベル放射性廃棄物（HLW）は使用済燃料の再処理においてUとPuを回収した後に残る高レベル廃液である．核燃料サイクルからは様々な放射性廃棄物が発生するが，それらの放射能の大半は使用済燃料中の核分裂生成物（FP）やアクチニド（Np, Am, Cm等）に起因するものであり、そのほとんど全てが最終的に高レベル廃液中に移行することから，放射能総量の観点からはHLWが最も重要な対象となる．高レベル廃液は，安全な取り扱い，保管，処分のため化学的に安定なガラス固化体とされ，地上施設で50年程度冷却保管により発熱量を減衰させた後，放射能が充分に減衰するまでの数万年間にわたる確実な隔離・閉じ込めのため地下300m以深の安定な地層中に幾つかの人工バリアを配して埋設処分（地層処分）される．なお，再処理を行わない場合は使用済燃料自身がHLWとなり同様に地層処分（直接処分）される． 4. バックエンド事業と研究・開発 　HLWの地層処分については「特定放射性廃棄物の最終処分に関する法律」成立（2000）の後，実施主体として原子力発電環境整備機構（NUMO）が設立（2000）され，公募方式による処分サイト選定が進められている．地層処分はサイト選定から建設・操業・閉鎖まで100年以上にわたる事業であり，社会的合意を得て実施に至るには，安全性に関する技術情報に加え，事業全体を見通して安全で効率的な処分実現のための基本的考え方や責任体制等を分かり易く示す必要がある．そのため日本全国を対象に処分場所としての科学的な適正可能性を示す「科学的特性マップ」（2017），安全な処分の実現に向けた技術や科学的知見を包括的に示した「包括的技術報告書」（2019予定）等の公開が進められている．一方，研究・開発については，地層処分が物理，化学，材料，地球科学，土木，等の多岐にわたる様々な分野の技術や知見を必要とする事から，それぞれの分野で研究・開発が進められているが，社会的合意を得るには様々な分野の技術や知見を「連携・統合」して処分全体としての正当性と信頼性を示す事も必要であり，連携・統合のための「技術マネジメント」の構築とそれを支える体制の拡充が望まれる．また，低レベル廃棄物や廃止措置との連携・統合，更には核燃料サイクル上流プロセスとの連携・統合をはかり，加えて様々な先端技術を取り込む事でサイクル全体としての真の能力を引き出すバックエンドを確立し、次世代の原子力利用の基盤につなげる事が望まれる．

開催年月日： 2018年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：岡山大学   国名：日本国  

開催年月日： 2018年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：岡山大学   国名：日本国  

開催年月日： 2018年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：岡山大学   国名：日本国  

開催年月日： 2017年11月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Osaka   国名：日本国  

開催年月日： 2017年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：久留米市   国名：日本国  

ガラス固化体の溶解は地下水中のMgとの相互作用により促進または抑制される結果が報告されている。これは生成されるMg含有鉱物の種類が環境条件によって複雑に変化し、ガラス溶解に与える影響も変化するためと考えられる。本研究では、国際標準ガラス（ISG）についてマイクロチャネル流水試験により、pH, Mg濃度をパラメータとした溶解試験を行い、その溶解挙動を評価した。

開催年月日： 2017年5月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Hawaii   国名：アメリカ合衆国  

開催年月日： 2017年5月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：Hawaii   国名：アメリカ合衆国  

開催年月日： 2017年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東海大学   国名：日本国  

開催年月日： 2017年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東海大学   国名：日本国  

開催年月日： 2016年9月

記述言語：日本語  

開催地：久留米   国名：日本国  

開催年月日： 2016年6月 - 2017年7月

記述言語：英語   会議種別：口頭発表（一般）  

開催地：パシフィコ横浜   国名：日本国  

ISG (International Simple Glass) is a six component alumina-borosilicate glass developed as reference bench-mark glass for six nations collaborating study on high-level nuclear waste glass dissolution kinetics [1]. In order to evaluate effects of environmental Mg on the dissolution kinetics of ISG, aqueous dissolution tests were performed at 90°C with MgCl2 solution at a constant pH (8.2) as a function of MgCl2 concentration by using Micro-Channel Flow-Through (MCFT) method [1]. The dissolution rate was measured for each glass constituent element as a function of reaction time, and the reacted glass surface was analyzed by use of SEM/EDX and XRD.

開催年月日： 2016年3月 - 2016年5月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：東北大学   国名：日本国  

福島第一原発事故の汚染水処理で発生したCs吸着ゼオライト廃棄物を安定化処理する方法の一つとして、溶融ガラス固化を検討した。溶融ガラス固化の処理条件が固化体の減容性、Cs固定化率、熱伝導、機械的特性、化学的耐久性等の諸特性に及ぼす影響を定性的、定量的に評価する事を目的とし、諸特性の測定に必要な大きさの固化体試料（40mm x 10mm x 5mm 以上）を作成するとともに、固化体の割れや気泡残留を抑制するための処理条件について検討した。

開催年月日： 2015年9月

記述言語：日本語   会議種別：口頭発表（一般）  

国名：日本国  

マイナーアクチニド分離変換技術の有効性向上のため、技術確立までの期間、再処理高レベル廃棄物を安定かつ再生可能な状態で冷却保管する柔軟な廃棄物管理法の研究開発を実施した。

開催年月日： 2015年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：茨城大学   国名：日本国  

福島第一原発事故の汚染水処理で発生したCs 吸着ゼオライトを合理的に処理する方法の一つとして、溶融ガラ ス固化を検討している。本研究では、溶融ガラス固化条件と固化体の諸特性との関係を定量的に評価することを目 的とし、Cs 固定化率の融剤添加量、溶融温度、溶融時間依存性をコールド試験において評価した。また137Cs トレ ーサーを用いたホット試験も実施し、そのCs 固定化率を評価した。

開催年月日： 2015年3月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：茨城大学   国名：日本国  

ガラス固化体は、地下水中に存在するMgとの反応によりマグネシウムシリケイトを生成することで、その溶解が促進または抑制される可能性が報告されている。本研究では、マイクロチャネル流水試験法を用いて、マグネシウムシリケイト生成挙動に影響を与えるMg濃度、Si濃度、pH等をパラメータとした溶解試験を行い、我が国の模擬ガラス固化体（P0798ガラス）の溶解挙動に及ぼす影響を評価した。

開催年月日： 2014年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：京都大学   国名：日本国  

福島第一原発事故の汚染水処理で発生したCs 吸着ゼオライトを合理的に処理する方法の一つとして検討されて いる溶融ガラス固化では、溶融温度やガラス融剤の添加量などの溶融ガラス固化条件が、減容率やCs 残存率、化 学的耐久性といった固化体の諸特性に影響する。本研究では、ガラス融剤の添加量、溶融温度／時間をパラメータ として、固化体の組織均一性、Cs 残存率を評価した。

開催年月日： 2014年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：京都大学   国名：日本国  

我々は新たに開発したマイクロチャネル流水試験法を用いて高レベルガラス固化体溶解挙動の精密な評価を進めている。本研究では、本試験法を用いて我が国の模擬ガラス固化体（P0798）の溶解速度を測定し、その測定精度を評価した。

開催年月日： 2014年5月

記述言語：英語  

開催地：Eurogress Aachen   国名：ドイツ連邦共和国  

For assessing long-term performance of high-level nuclear waste (HLW) glass in geological disposal, kinetics of the aqueous corrosion under near silica-saturation conditions is one of fundamental subjects to be evaluated. In the present study, aqueous corrosion tests were performed for International Simple Glass (ISG) by using Micro -Channel Flow-Through (MCFT) method to evaluate the corrosion rate under silica -saturation condition. The ISG is a six-component alumino-borosilicate glass developed as a reference benchmark glass for six nations collaborating study on HLW glass dissolution/corrosion mechanism. The corrosion tests were conducted at the temperature range of 25-70 °C with the solution saturated with respect to amorphous silica at pH9. The test results showed that the corrosion rate based on boron release under the silica-saturation condition is slower than that under silica-free condition or the initial dissolution rate by a factor of only up to 10. The presentation will focus on the corrosion mechanism of the ISG in comparison with other simulated HLW glasses.

開催年月日： 2012年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：広島大学   国名：日本国  

放射性ヨウ素廃棄物処分のための基礎研究として、還元雰囲気における岩石固化体の溶解挙動の評価を目的とし、還元雰囲気において岩石固化体の溶解実験をHS-濃度をパラメーターとして行った。

開催年月日： 2012年9月

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：広島大学   国名：日本国  

我が国の標準模擬ガラス固化体(P0798ガラス)について、残存溶解速度の測定・評価を目的とし、Si飽和またはAl飽和溶液を用い、pHをパラメータとした溶解試験を行なった。

開催年月日： 2011年12月

会議種別：口頭発表（一般）  

国名：日本国  

開催年月日： 2011年5月

会議種別：口頭発表（一般）  

開催地：Savannah, USA   国名：アメリカ合衆国  

開催年月日： 2011年1月

開催地：Manchester   国名：グレートブリテン・北アイルランド連合王国(英国)  

開催年月日： 2010年9月

開催地：北海道大学   国名：日本国  

開催年月日： 2010年9月

開催地：北海道大学   国名：日本国  

開催年月日： 2010年5月

会議種別：口頭発表（一般）  

開催地：Corning, NY   国名：アメリカ合衆国  

A new type of flow-through test method using micro-reactor was developed and applied to measurement of dissolution kinetics for a Japanese simulated HLW glass, P0798. In this method, a coupon shaped glass is placed on a Teflon plate with a micro-channel (20mm x 2mm x 0.16mm), and a solution is injected into the inlet of the channel at a constant flow rate. The outlet solution, which reacted with glass through the channel, is retrieved to be analyzed for determination of the dissolution rate. By using this method we measured the initial dissolution rate as a function of pH and temperature. The results showed that the initial dissolution rate has “V-shaped” pH dependence at any temp. from 25 to 90°C similar to that for R7T7 glass evaluated by CEA, France. However, a certain difference was observed between them in the temp. dependence at high pHs. Based on the results and comparison, we discussed the dissolution kinetics.

開催年月日： 2009年9月

会議種別：口頭発表（一般）  

開催地：東北大学   国名：日本国  

Sorption of silica on corrosion products of iron under reducing condition

開催年月日： 2009年5月

開催地：St.Petersburg   国名：ロシア連邦  

We applied a new type of flow-through test method using micro-reactor consisting of a simple test apparatus with compact size to measurement of the dissolution rate of a Japanese type of simulated waste glass (P0798 glass).

開催年月日： 2008年9月

会議種別：口頭発表（一般）  

国名：日本国  

Dissolution rate of HLW glass as a function of pH measured by micro-rector flow-through test

開催年月日： 2008年3月

会議種別：シンポジウム・ワークショップ パネル（公募）  

国名：日本国  

開催年月日： 2007年9月

国名：日本国  

会議種別：シンポジウム・ワークショップ パネル（公募）  

国名：ベルギー王国  

Several kinetic models have been proposed to predict the aqueous dissolution/ alteration rate of nuclear waste glass for long-term. However, reaction processes controlling the long-term rate are much more subjected to controvert. Temperature dependence of the alteration rate is one of essential issues to be evaluated for an understanding of the rate controlling processes. In the present study, the static alteration tests were performed with a Japanese simulated waste glass P0798 as a function of temperature from 60。C to120。C, and the temperature dependence of the alteration rate was evaluated to understand the rate controlling processes. The tests were performed in 0.001M NaOH solution to maintain a constant solution pH of around 10 during the test period and to provide smectite forming conditions where smectite forms as the major secondary phase without zeolite formation. From the test results on dissolution of boron, the alteration rate at each temperature was analyzed by use of a water-diffusion model. The water-diffusion model used is based on a simple assumption; the glass alteration proceeds being controlled by water diffusion with ion-exchange between water (hydronium ion: H3O+) and soluble elements(B, Na, Li, etc) at the glass surface layer with the apparent diffusion coefficient of Di. A good agreement was observed between the model analysis and the test results, and the value of Di was evaluated to be 1.2 x 10-22 m2/s at 60。C to 1.8 x 10-21 m2/s at 120。C. The Arrhenius plot of Di showed a good linearity to give the activation energy of 49 kJ/mol, which value is much lower than that for the initial dissolution rate of French waste glass(71 kJ/mol) by Delage[1] and Techer[2], but is very close to that for ion-exchange in sodium aluminosilicate glass by McGrail[3]. These results suggest that water diffusion with ion-exchange can be the dominant process controlling the alteration rate under smectite forming conditions. At elevated temperatures(100。C and 120。C), however, the model analysis deviated from the test results, which suggests that the precipitated layer developing at the glass surface can be protective against the diffusion to depress the alteration rate.

会議種別：口頭発表（一般）  

国名：アメリカ合衆国  

会議種別：口頭発表（一般）  

開催地：名古屋大学   国名：日本国  

記述言語：日本語   会議種別：口頭発表（一般）  

開催地：近畿大学   国名：日本国  

米仏日を中心とするガラス固化体研究国際チームで作製した、組成を単純化した国際標準ガラスについて、マイクロチャネルリアクタ流水溶解試験により、初期溶解速度(ro)のpH／温度依存性を評価した。

記述言語：日本語  

開催地：近畿大学   国名：日本国  

ヨウ素廃棄物岩石固化体の地下還元環境における溶解メカニズムの理解を目的とし、(Ar+5%H2）ガス置換グローブボックス中でNa2S水溶液を反応溶液として岩石固化体の溶解実験を行った。

記述言語：英語  

開催地：Hotel DelCoronado, SanDiego, California, USA   国名：日本国  

Magnesium is one of major elements dissolved in groundwaters, and is expected to affect dissolution behavior of HLW glass in geological disposal. Some of previous studies have reported that the presence of magnesium in solutions can accelerate the glass dissolution by precipitation of magnesium-silicates consuming dissolved silica in solutions. While some studies have reported that the presence of magnesium can depress the glass dissolution under certain conditions. Comparison of these previous studies suggests that the effects of magnesium on the glass dissolution rate can change sensitively depending on the dissolution conditions such as pH, temperature, solution composition, S/V and time, and we need precise and consistent experimental data measured systematically under various well-constrained conditions for greater understandings of kinetics of the glass dissolution in the presence of magnesium. In the present study, therefore, aqueous dissolution/alteration tests were performed for P0798 simulated HLW glass in MgCl2 solution by using “Micro-channel flow-through test method” to measure the dissolution rate precisely as a function of pH. On the basis of the test results including solid phase analyses of the reacted glass surface, this presentation discusses the kinetics of the glass dissolution in the presence of magnesium.

記述言語：英語  

開催地：Conference site at Pont du Gard, France   国名：日本国  

In this lecture, several test methods currently applied to measurement of the glass dissolution kinetics are introduced with their advantages and disadvantages, and problems to be solved for a greater understanding of the glass dissolution kinetics are discussed.

種別：査読等 

外国語雑誌　査読論文数：3

種別：査読等 

外国語雑誌　査読論文数：3

種別：査読等 

外国語雑誌　査読論文数：5

種別：査読等 

外国語雑誌　査読論文数：5

種別：大会・シンポジウム等 

参加者数：1,000

種別：大会・シンポジウム等 

種別：大会・シンポジウム等 

種別：大会・シンポジウム等 

参加者数：800

種別：大会・シンポジウム等 

参加者数：30

種別：大会・シンポジウム等 

参加者数：1,000

種別：大会・シンポジウム等 

参加者数：1,000

種別：大会・シンポジウム等 

種別：大会・シンポジウム等 

種別：大会・シンポジウム等 

参加者数：1,000

種別：大会・シンポジウム等 

種別：大会・シンポジウム等 

種別：大会・シンポジウム等 

種別：大会・シンポジウム等 

種別：学会・研究会等 

種別：大会・シンポジウム等 

種別：大会・シンポジウム等 

種別：大会・シンポジウム等 

参加者数：400

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：研究指導

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：研究指導

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：研究指導

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：研究指導

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：研究指導

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：社会人・一般,　学術団体,　企業,　市民団体,　行政機関

種別：研究指導

日本原子力学会バックエンド部会において「福島除染基礎勉強会」を設立し、福島市において一般市民を対象に勉強会を開催した。（平成24年1月、3月）

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ

対象：幼稚園以下,　小学生,　中学生,　高校生

種別：セミナー・ワークショップ