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One of the main chemical forms of cesium in the gas phase during severe light-water reactor accidents is expected to be cesium metaborate, CsBO 2 , according to thermodynamic equilibrium calculations considering its reaction with boron. However, the accuracy of the thermodynamic data of the gaseous metaborate, CsBO 2 (g), has been judged as poor. Thus, Knudsen effusion mass spectrometric measurements of CsBO 2 were carried out to obtain reliable thermodynamic data. The evaluated values of the standard enthalpy of formation of CsBO 2 (g), obtained by the 2nd and 3rd-law treatments, are −700.7 ± 10.7 kJ/mol and −697.0 ± 10.6 kJ/mol, respectively, and agree with each other within the experimental errors, which indicates that our data are reliable. Furthermore, it was found that the existing data of the Gibbs energy function and the standard enthalpy of formation agreed well with the values evaluated in this study, which indicates that the existing thermodynamic data are also reliable.

Ultra-high temperature ring tensile tests were performed to investigate the tensile behavior of oxide dispersion strengthened (ODS) steel claddings and wrapper materials under severe accident conditions with temperatures ranging from room temperature to 1400 °C which is close to the melting point of core materials. The experimental results showed that the tensile strength of 9Cr-ODS steel claddings was highest in the core materials at ultra-high temperatures of 900–1200 °C, but there was significant degradation in the tensile strength of 9Cr-ODS steel claddings above 1200 °C. This degradation was attributed to grain boundary sliding deformation with γ/δ transformation, which is associated with reduced ductility. By contrast, the tensile strength of recrystallized 12Cr-ODS and FeCrAl-ODS steel claddings retained its high value above 1200 °C, unlike the other tested materials.

Three different partners, ENEA, JAEA ed University of Tokyo, have been involved during 2014-2015 in the Round Robin experimentation for the assessment of the soundness of the analitycal procedure for the determination of the Nitrogen impurities contained inside a solid Lithium sample. Two different kinds of Lithium samples, differing by about an order of magnitude in Nitrogen concentration (∼230 wppm; ∼20-30 wppm), have been selected for this cross analysis. The agreement of the achieved results appears very good for what concerns the most concentrated Lithium and indicates each partner's procedure is appropriate and intrinsecally able to lead to meaningful values, characterized by a relative uncertainty of just few %. The smaller agreement in the case of the less concentrated Lithium anyway points out that particular attention must be paid to reduce as much as possible any source of external contamination and highlights the importance of the proper blank subtraction. © 2016 EURATOM-ENEA.

The International Fusion Materials Irradiation Facility (IFMIF), presently in the Engineering Validation and Engineering Design Activities (EVEDA) phase was started from 2007 under the frame of the Broader Approach (BA) agreement. In the activities, a prototype Li loop with the world's highest flow rate of 3000 L/min was constructed in 2010, and it succeeded in generating a 100 mm wide and 25 mm thick with a free-surface lithium flow along a concave back plate steadily at a high-speed of 15 m/s at 250 °C for 1300 h. In the demonstration operation it was needed to develop the Li flowing measurement system with precious resolution less than 0.1 mm, and a new wave height measuring method which is laser-probe method was developed for measurements of the 3D geometry of the liquid Li target surface. Using the device, the stability of the variation in the Li flowing thickness which is required in the IFMIF specification was ± 1 mm or less as the liquid Li target, and the result was satisfied with it and the feasibility of the long-term stable liquid Li flow was also verified. The results of the other engineering validation tests such as lithium purification tests of lithium target facility have also been evaluated and summarized.

Aflatoxin contamination of crops is a serious problem impacting human health and the economy. Utilization of aflatoxin production inhibitors is attractive, as the elucidation of their modes of action provides clues to clarify the mechanism of aflatoxin production. Here, we identified mitochondrial protease ClpP as the molecular target of dioctatin, an inhibitor of aflatoxin production of Aspergillus flavus. Dioctatin conferred uncontrolled caseinolytic capacity on ClpP of A. flavus and Escherichia coli. Proteomic analysis showed that dioctatin-bound ClpP selectively degraded mitochondrial energy-related proteins, such as subunits of respiratory complexes and the pyruvate dehydrogenase complex. Dioctatin enhanced glycolysis and alcohol fermentation while reducing tricarboxylic acid cycle metabolites. These metabolic shifts accompanied the reduction of histone acetylation, leading to the downregulation of aflatoxin production. Our results suggest the existence of an exquisite balance between aflatoxin production and alcohol fermentation, with mitochondrial status serving as a key determinant of this balance.

Mirror maps play an important role in studying supersymmetric gauge theories. In these theories the dynamics is often encoded in an algebraic curve where two sets of periods enjoy the symplectic structure. The A-periods contribute to redefinitions of chemical potentials known as mirror maps. Using the quantization of the $D_5$ del Pezzo geometry, which enjoys the symmetry of the $D_5$ Weyl group, we are able to identify clearly the group-theoretical structure and the multi-covering structure for the mirror map. With the structures, we can apply the mirror map to superconformal Chern-Simons theories describing the worldvolume of multiple M2-branes on various backgrounds, where we find that the redefinition of the chemical potential is obtained directly from the mirror map. Besides, we have interesting observations for the mirror map: The representations appearing in the quantum mirror map are the same as those appearing in the BPS indices except for the trivial case of degree 1 and the coefficients are all integers., Comment: 22 pages, 1 eps figure; v5: minor changes, published version

In the framework of the Engineering Validation and Engineering Design Activities (EVEDA) project of the International Fusion Materials Irradiation Facility (IFMIF), we measured surface velocity fields of a lithium (Li) target at the EVEDA Li test loop under specifically-designated IFMIF conditions (target speeds of 10, 15, and 20 m/s, vacuum pressure of 10−3 Pa, and Li temperature of 250 °C). In the current design of the IFMIF, the free surface of the Li target is under a most severe heat load condition with respect to Li boiling. The objective of this study is to measure the actual free-surface velocity under these IFMIF conditions to evaluate the heat removal performance of the Li target. The measured results (using the surface-wave tracking method that our team developed) showed two-dimensional time-averaged velocity distributions around the IFMIF beam footprint being virtually uniform, and close to the cross-sectional average velocity. The uniformity of the velocity distributions was less than 1 m/s. The comparison between the measured and analyzed surface velocity at the beam center showed that the analysis accurately predicts the measurement results within a margin of 3%. Finally, it was confirmed that the Li target delivers adequate heat removal performance in the IFMIF as designed.

The International Fusion Materials Irradiation Facility (IFMIF) is an accelerator-based D + -Li neutron source in which two 40-MeV-D + beams with a total current of 250 mA are injected into a liquid Li stream flowing at 15 m/s (Li target). The EVEDA Li test loop (ELTL), which simulates the hydraulic conditions of the Li target and a part of the purification system envisaged in IFMIF, is a main activity in the Li target facility of the IFMIF/EVEDA project and has been implemented under the Broader Approach (BA) agreement since 2007. The key issues to be validated in ELTL were as follows: (1) validation of the Li target, Li target diagnostics, and cold trap (CT), and (2) validation of long-term operation. This study describes the stability of the Li target in an integrated long-term operation run of the entire system as a demonstration of the IFMIF Li target facility. The Li target was continuously operated with the CT for 571 h, and its stability was evaluated periodically using a high-precision Li target diagnostic. Therefore, the Li target essentially satisfied the stability requirement of

The FeCrAl-oxide dispersion strengthened (ODS) alloy is the promising cladding material for the accident-tolerant fuel (ATF) of the light water reactors (LWR) to suppress the oxidation reaction with hot steam by Al2O3 formation. Ring-creep tests for FeCrAl-ODS alloy cladding were carried out at 973 K and 1273 K to evaluate the deformation mechanism at the sever accident. The temperature-compensated strain rate by Fe-diffusion coefficient versus the normalized stress by shear modulus was constructed. The dislocation detachment stress from the dispersoid was derived by considering the dislocation-dispersoid elastic interaction and the dislocation relaxation effect by climb motion. When the applied stress exceeds the dislocation detachment stress, dislocations overcome the dispersoids with the reduced values of the stress exponent, which is attributed to the dislocation climb motion. When the stress is lower than the dislocation detachment stress, large size of cavities exists at the grain boundaries. Grain boundary sliding (GBS) is dominant factor for the low strain rate creep deformation at 1273 K, where dislocation climb also plays a critical role for release of the stress concentration induced by GBS. Based on those findings, new constitutive equations for creep deformation were constructed, which is applicable to low stress, low strain rate and high temperature conditions encountered at the reactor sever accident.

The International Fusion Material Irradiation Facility (IFMIF) is an experimental facility conceived for qualifying and characterizing structural materials for nuclear fusion applications. The Engineering Validation and Engineering Design Activity (EVEDA) is a fundamental step towards the final design. It presented two mandates: the Engineering Validation Activities (EVA), still on-going, and the Engineering Design Activities (EDA) accomplished on schedule in June 2013. Five main facilities are identified in IFMIF, among which the Lithium Target Facility constituted a technological challenge overcome thanks to the success of the main validation challenges impacting the design. The design of the liquid Lithium Target Facility at the end of the EDA phase is here detailed. © 2015 Elsevier B.V. All rights reserved.

In the International Fusion Materials Irradiation Facility (IFMIF), a back plate of the target assembly will be exchanged during the in-service period. During the works, the lithium components will react chemically with the surrounding atmosphere. In this research, the chemical reaction of lithium in air, oxygen and nitrogen containing variable humidity at room temperature has been investigated to estimate the chemical reaction during the exchange works., 国際核融合材料照射試験施設(IFMIF)では、ターゲットアッセンブリのバックプレートは、供用期間中に交換される予定である。この交換作業において、バックプレート等のリチウム機器は、周辺の大気成分と化学反応を生じることが想定される。そこで本研究では、当該交換作業期間中における化学反応挙動を評価するために、リチウムと大気、および大気中の主要元素である酸素および窒素の室温における化学反応挙動について、気中の湿度の影響も加味しながら実験的に調べた。

A liquid-Li free-surface stream flowing at 15 m/s under a high vacuum of 10 −3 Pa is to serve as a beam target for the planned International Fusion Materials Irradiation Facility (IFMIF). The Engineering Validation and Engineering Design Activities (EVEDA) for the IFMIF is implemented under the Broader Approach. As a major activity for the Li target, the EVEDA Li test loop (ELTL) was constructed by the Japan Atomic Energy Agency. The present study demonstrates a stable Li target that satisfies the IFMIF design conditions (250 °C, 15 m/s, 10 −3 Pa) and presents the procedure for operating the Li target which consists of seven stages. We used a laser-based method to verify that the Li target is adequately stable. In addition, we examine cavitation occurring during startup of the Li target, and consequently, determine the appropriate startup pressure.

A high-speed (nominal: 15 m/s, range: 10–16 m/s) liquid lithium wall jet is planned to serve as the target for two 40 MeV and 125 mA deuteron beams in the International Fusion Materials Irradiation Facility (IFMIF). The design requirement of target thickness stability is 25 ± 1 mm under a vacuum of 10 −3 Pa. This paper presents the results of the target thickness measurement conducted in the EVEDA Li Test Loop under a wide range of conditions including the IFMIF condition (target speed of 10, 15, and 20 m/s; vacuum pressure of 10 −3 Pa; and Li temperature of 250 °C). For measurement, we use a laser probe method that we developed in advance; this method generates statistical measurements method using a laser distance meter. The measurement results obtained under the IFMIF nominal condition (15 m/s, 10 −3 Pa, 250 °C) at the IFMIF beam center are as follows: average target thickness = 26.08 ± 0.09 mm (2 σ ), mean wave amplitude = 0.26 ± 0.01 mm (2 σ ), and maximum wave amplitude = 1.46 ± 0.25 mm (2 σ ). Of the total wave components, 99.7% are within the design requirement. The analytically predicted target thickness is in excellent agreement with the experimental data, resulting in successful characterization of the Li target thickness.

A key problem in the application of a supercritical CO2 turbine cycle to a fast breeder reactor is the corrosion of structural materials brought about by supercritical CO2 at high temperatures. In this study, metallurgical analysis of the ferritic–martensitic steels (12Cr-steel and T91) exposed at 400–600 °C for up to 8000 h in supercritical CO2 pressurized at 20 MPa and at 550 °C for up to 5000 h in CO2 gas at atmospheric pressure has been carried out. Two successive oxide layers formed on the steels were kept under the maximum testing conditions (at 600 °C for 8000 h at 20 MPa), and no breakaway corrosion was observed. Each oxide layer thickness increased with exposure time, due to parabolic oxide growth. By using the electron backscattering diffraction technique, the outer oxide layer could be separable into thin Fe2O3 and thick Fe3O4, and the formation behavior was clarified. Carburizing was observed in the base metal just under the oxide layer, and the crystal structure was mainly M23C6.

Studies for establishing technology for the safe handling of lithium was performed in the Engineering Validation and Engineering Design Activities (EVEDA) for the International Fusion Material Irradiation Facility (IFMIF). This research comprises four tasks: (a) extinguishing lithium files, (b) chemical reactions of lithium on the event of a leak, (c) lithium removal from the components, and (d) chemical analysis of impurities in lithium. Tasks (a) and (b), related to functions on the event of a lithium leak, involve selection of the material suitable for extinguishing lithium fires and assessment of corrosive effects of leaked lithium on materials at high temperature, respectively. Task (c) involves evaluation of methods for the replacement and/or decommissioning of the lithium components. Task (d) constitutes the development of high-precision techniques for the determination of impurities in lithium, particularly the dominating corrosive impurity—dissolved nitrogen. Experimental results addressing the objectives of each of the tasks are described in this communication.

It was proved by Macdonald that the Giambelli identity holds if we define the Schur functions using the Jacobi-Trudi identity. Previously for the super Chern-Simons matrix model (the spherical one-point function of the superconformal Chern-Simons theory describing the worldvolume of the M2-branes) the Giambelli identity was proved from a shifted version of it. With the same shifted Giambelli identity we can further prove the Jacobi-Trudi identity, which strongly suggests an integrable structure for this matrix model.

The intracellular superoxide level is a clue to clarification of the regulatory mechanism for mycotoxin production in Fusarium graminearum. In this study, we focused on two manganese superoxide dismutases (SODs) of the fungus, FgSOD2 and FgSOD3, to investigate the relationship of the superoxide level to trichothecene production. Recombinant FgSOD2 and FgSOD3 showed SOD activity, and they were localized mainly in the mitochondria and cytoplasm, respectively. Trichothecene production and mRNA levels of Tri5 and Tri6, which encode a trichothecene biosynthetic enzyme and a key regulator of trichothecene production, respectively, were greatly reduced in gene-deletion mutants of FgSod2 and FgSod3 (ΔFgSod2 and ΔFgSod3). Significant increases in the cytosolic and mitochondrial superoxide levels were observed in ΔFgSod2 and ΔFgSod3, respectively. These results suggested that the cellular superoxide level affects trichothecene production in F. graminearum.

in turn, the commissioning of the 5 MeV beam is due to start during 2017. The D+ beam through the superconducting cavities is expected to be achieved within the Broader Approach Agreement time frame with the superconducting cryomodule being assembled in Rokkasho. The realisation of a fusion-relevant neutron source is a necessary step for the successful development of fusion. The ongoing success of the IFMIF/EVEDA involves ruling out concerns about potential technical showstoppers which were raised in the past. Thus, a situation has emerged where soon steps towards constructing a Li(d,xn) fusion-relevant neutron source could be taken, which is also justified in the light of costs which are marginal to those of a fusion plant. © 2017 IAEA, Vienna., IFMIF, the International Fusion Materials Irradiation Facility, is presently in its engineering validation and engineering design activities (EVEDA) phase under the Broader Approach Agreement. The engineering design activity (EDA) phase was successfully accomplished within the allocated time. The engineering validation activity (EVA) phase has focused on validating the Accelerator Facility (AF), the Target Facility and the Test Facility (TF) by constructing prototypes. The ELTL at JAEAc, Oarai successfully demonstrated the long-term stability of a Li flow under the IFMIF's nominal operational conditions keeping the specified free-surface fluctuations below 1 mm in a continuous manner for 25 d. A full-scale prototype of the high flux test module (HFTM) was successfully tested in the HELOKA loop (KIT, Karlsruhe), where it was demonstrated that the irradiation temperature can be set individually and kept uniform. LIPAc, designed and constructed in European labs under the coordination of F4E, presently under installation and commissioning in the Rokkasho Fusion Institute, aims at validating the concept of IFMIF accelerators with a D+ beam of 125 mA continuous wave (CW) and 9 MeV. The commissioning phases of the H+/D+ beams at 100 keV are progressing and should be concluded in 2017

A liquid Li jet flowing at 15 m/s under a high vacuum of 10−3 Pa is intended to serve as a beam target (Li target) in the planned International Fusion Materials Irradiation Facility (IFMIF). The engineering validation and engineering design activities (EVEDA) for the IFMIF are being implemented under the broader approach (BA) agreement. As a major activity of the Li target facility, the EVEDA Li test loop (ELTL) was constructed by the Japan Atomic Energy Agency. A stable Li target under the IFMIF conditions (Li temperature: 523.15 K, velocity: 15 m/s, and vacuum pressure: 10−3 Pa) was demonstrated using ELTL. This study focuses on a cavitationlike acoustic noise detected in a downstream conduit where the Li target flowed under vacuum conditions. This noise was investigated using acoustic-emission (AE) sensors installed at eight locations via acoustic wave guides. The sound intensity of the acoustic noise was examined against the cavitation number of the Li target. In addition, two types of frequency analysis, namely, fast Fourier transform (FFT) and continuous wavelet transform (CWT), were performed to characterize the acoustic noise. Owing to the acoustic noise's intermittency, high frequency, and the dependence on cavitation number, we conclude that this acoustic noise is generated when cavitation bubbles collapse and/or the structural material of the pipe is cracked because of the collapse of cavitation bubbles (cavitation pitting). The location of the cavitation was fundamental for presuming the mechanism. In this study, the propagation of acoustic waves among AE sensors placed at three locations was used to localize the cavitation and a method to determine the location of cavitation was formulated. As a result, we found that cavitation occurred only in a narrow area where the Li target impinged on the downstream conduit; therefore, we concluded that this cavitation was induced by the impingement. The design of the downstream conduit of the IFMIF Li target facility should be tackled in future based on information obtained in this study.

Engineering Validation and Engineering Design Activities (EVEDA) for the International Fusion Materials Irradiation Facility (IFMIF) have been carried out under the “Broader Approach” (BA) agreement. As a major activity for the Li target facility, the EVEDA Li test loop (ELTL) was constructed at the Japan Atomic Energy Agency's Oarai site to validate the hydraulic conditions of the IFMIF Li target. This paper presents the first operational results of the Li target in the ELTL. A series of tests were performed to check the operational performance of the Li target. The conclusions are as follows: (1) the start-up procedure of the Li target was examined and consequently achieved the Li target and (2) the Li target whose velocity was 20 m/s under pressurized and vacuum conditions was observed by image devices and confirmed to be stable.

A technique was needed for measuring the thickness of the liquid lithium target of the International Fusion Materials Irradiation Facility (IFMIF 1 ). Thus, the applicability of a laser-based distance meter was evaluated within the framework of Engineering Validation and Engineering Design Activities (EVEDA) of IFMIF. This device is usually used against diffuse objects. However, in the present case, it is used against specular, finely deformed liquid metal surfaces. Both the measurement resolution and precision are required to be 0.1 mm or less to measure the thickness variation of ±1 mm. To ensure sufficient power of the reflected laser from the liquid metal surface, the laser spot diameter was set to 0.1 mm, considering previous experimental data regarding the dominant wavelength of surface waves. An experiment was conducted at the Osaka University Li loop in the velocity range 10–15 m/s and Li temperature of 300 °C under an argon atmosphere of 0.12 MPa. The experimental results showed that the laser-based distance meter can be used to measure the Li-jet thickness at a jet velocity of up to 15 m/s and with superior precision at 16 μm, which is a much more precise value than required.

A lithium test assembly used for lithium-free surface flow experiments at 300 °C for 1200 h at Osaka University was analyzed metallographically to verify the design of the lithium target of the International Fusion Materials Irradiation Facility (IFMIF). Certain irregularities such as traces of high-speed lithium flow at a maximum velocity of 15 m/s were observed at the tip of the nozzle. Mottled unevenness with numerous microcracks a few microns deep was detected at the inlet of the nozzle, the velocity ratio of which was 0.1–0.4 as compared with the nozzle tip. A thin, altered layer developed on the surface of these regions because of carbide formation. It is believed that the microcracks were nucleated by thermal transients at the start or stop of operations of the lithium loop. These slight irregularities could be the result of exfoliation of the altered layer because of the high-speed lithium flow caused by the increased hardness of the altered layer as compared with that of the base metal. The metallurgical analysis proved for the first time that carbon control in lithium is also important for corrosion and erosion protection of the IFMIF components.

High-temperature lithium, which is used as the neutron source in the International Fusion Material Irradiation Facility, reacts with oxygen, nitrogen, and moisture in the atmosphere. We estimated which lithium compounds might be stable under environmental conditions by using chemical equilibrium calculations, then performed austenitic stainless steel corrosion tests with the selected lithium compounds. The lithium compounds (reagents) and a steel specimen were heated to 1120 K in an Al 2 O 3 Tammann crucible. After the test, the steel specimen was cleaned with alcohol and water and then weighed and metallurgically examined. We found that the steel was significantly corroded in Li 3 N, LiOH, and Li 2 O 2 environments. Because Li 2 O 2 is not stable according to the chemical equilibrium calculations, corrosion by Li 3 N and LiOH needs to be considered in high-temperature lithium applications.

The IFMIF presents an intense neutron source to develop fusion reactor materials. The free surface flow of a liquid metal Li is planned as a target irradiated by two deuteron beams to generate intense neutrons and it is thus important to obtain information on the surface wave characteristic for the safety and the efficiency of system in the IFMIF. We have been studying on surface wave characteristics numerically using computational fluid dynamics code in order to establish the mechanism of the formation and the development of the free surface wave of the Li jet. This paper reports results of the Li free surface flow simulation using large eddy simulation and volume of fluid as the turbulence model and the interface tracking method, respectively, including the inside of a two-staged contraction nozzle. In our simulation, two cases of velocities of 9 and 15 m/s at the nozzle exit were conducted as the flow condition from the nozzle exit to 20 mm downstream. It is found that the surface wave transits to the three-dimensional wave mode induced by both longitudinal and transverse vortices at the position of 15 mm downstream in the case of the velocity of 15 m/s.

CdSe quantum dots are often used in industry as fluorescent materials. In this study, CdSe quantum dots were synthesized using Fusarium oxysporum. The cadmium and selenium concentration, pH, and temperature for the culture of F. oxysporum (Fusarium oxysporum) were optimized for the synthesis, and the CdSe quantum dots obtained from the mycelial cells of F. oxysporum were observed by transmission electron microscopy. Ultra-thin sections of F. oxysporum showed that the CdSe quantum dots were precipitated in the intracellular space, indicating that cadmium and selenium ions were incorporated into the cell and that the quantum dots were synthesized with intracellular metabolites. To reveal differences in F. oxysporum metabolism, cell extracts of F. oxysporum, before and after CdSe synthesis, were compared using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The results suggested that the amount of superoxide dismutase (SOD) decreased after CdSe synthesis. Fluorescence microscopy revealed that cytoplasmic superoxide increased significantly after CdSe synthesis. The accumulation of superoxide may increase the expression of various metabolites that play a role in reducing Se4+ to Se2− and inhibit the aggregation of CdSe to make nanoparticles.

Inhibitors of aflatoxin production of aflatoxigenic fungi are useful for preventing aflatoxin contamination in crops. As methyl syringate weakly inhibits aflatoxin production, aflatoxin production inhibitory activities of additional alkyl syringates with alkyl chains from ethyl to octyl were examined. Inhibitory activity toward aflatoxin production of Aspergillus flavus became stronger as the length of the alkyl chains on the esters became longer. Pentyl, hexyl, heptyl, and octyl syringates showed strong activity at 0.05 mM. Heptyl and octyl parabens, and octyl gallate also inhibited aflatoxin production as strongly as octyl syringate. Alkyl parabens and alkyl gallates inhibit the complex II activity of the mitochondrial respiration chain; thus, whether alkyl syringates inhibit complex II activity was examined. Inhibitory activities of alkyl syringates toward complex II also became stronger as the length of the alkyl chains increased. The complex II inhibitory activity of octyl syringate was comparable to that of octyl paraben and octyl gallate. These results suggest that alkyl syringates, alkyl parabens, and alkyl gallates, including commonly used food additives, are useful for aflatoxin control.

The effectiveness of Al addition for improvement of the corrosion resistance of ODS steel in lead–bismuth eutectic (LBE) was investigated. Al-alloying surface treatment using a GESA facility was applied to 9Cr-ODS martensitic steel, and the corrosion resistance in stagnant LBE containing 10−6 wt% oxygen was subsequently examined. Corrosion resistance of ODS ferritic steels with high Cr content (14.7 wt%), containing 3.3–3.8 wt% Al and small amounts of Zr or Hf, was also examined. Al-alloying surface treated 9Cr-ODS martensitic steel was tested at 650 °C and ODS ferritic steels with high Cr content, containing 3.3–3.8 wt% Al and small amounts of Zr or Hf, were tested at 650 and 700 °C. The maximum exposure duration was 10,000 h. All tested materials showed good corrosion resistance under all test conditions. Both the Al-alloying surface treatment by the GESA facility and the Al addition to the matrix with small amounts of Zr or Hf effectively improved the compatibility of ODS steel with LBE at high temperatures.

In the Engineering Validation and Engineering Design Activities (EVEDA) on the International Fusion Materials Irradiation Facility (IFMIF), hydraulic stability of a liquid Li jet simulating the IFMIF Li target is planned to be validated in the EVEDA Li Test Loop (ELTL). This paper presents the engineering design of a contact-type liquid level sensor for use in ELTL. The sensor is going to be utilized to measure variation of jet thickness in the validation test on hydraulic stability of the Li jet, which is one of the major key tests to be performed in ELTL. A fundamental requirement for the engineering specification of the sensor is to ensure the position accuracy of the measurement probe against the pressure load of approximately 0.1 MPa between the inside and the outside of the test chamber. The calculation result on structural strength of the sensor with a Nastran code showed that the maximum displacement was 0.65 mm and that the sensor has adequate strength against the pressure load. The calcu...

Titanium plates coated by iron were fabricated electrochemically as a candidate hydrogen isotope permeation window for liquid lithium. Contacting the window to liquid lithium containing deuterium between 673 and 873 K, its permeation behavior and resistance to degradation were investigated. The iron-coated window showed less permeability than the bare titanium window as well as good agreement with the theoretical value. Furthermore, the iron layer at the vacuum side surface strongly improved oxidation resistance. Decrease of permeability for 2 hours air exposure could be recovered within 30 hours in the case of the coated window, while that of the bare titanium window could not. The coated permeation window is promising regarding high permeability and antidegradation properties.

In IFMIF/EVEDA, tasks for lithium target system consist of 5 validation tasks (LF1-5) and a design task (LF6), and are shared by Japan and Europe. Japan is covering LF1, LF2, LF4, LF5 and LF6, and JAEA as an Implementing Agency is organizing these tasks. Japanese universities contribute these tasks. The purpose of LF1 task is to construct and operate EVEDA Li test loop (ELTL) with diagnostics and purification systems for the validation of Li target facility. ELTL will be constructed at the end of February in 2011 and the operation will be started at the summer in 2011. LF2 and LF4 are basic research for the diagnostics and purification system, respectively. And LF2 and LF4 have also contributed the construction of the ELTL (LF1). LF5 is focusing on the remote handling for the replacement of the target assembly. Major deliverable of LF6 is finally engineering design report, which is assembled with all validation tasks, and this activity will be gradually enhanced to the end of IFMIF/EVEDA.

In order to obtain engineering data on the lithium target system, which is the neutron source of the International Fusion Material Irradiation Facility (IFMIF), design and fabrication of the EVEDA Lithium Test Loop (ELTL) are being carried out under Engineering Validation and Engineering Design Activity (EVEDA). The ELTL holds 2500 kg of lithium. Since lithium is specified by Japanese law as a dangerous substance as in sodium, coolant for fast reactors, countermeasures which assume a lithium leak and other abnormalities are indispensable. This paper describes safety principles and measures decided under the detailed design process.

Engineering Validation and Engineering Design Activities (EVEDA) for the International Fusion Materials Irradiation Facility (IFMIF) were started under a collaborative international project known as the ITER Broader Approach. This paper presents the design of a cold trap for reducing oxygen concentration in Li installed in a purification loop of the EVEDA Li Test Loop (ELTL). Oxygen concentration during operation of the ELTL was estimated and the cold trap is designed with reference to the design of sodium cold trap developed for fast breeder reactor research. The presumed values in this design are expected to be reevaluated through the ELTL test program by using off- and on-line impurity monitors.

Nitrogen trapping is a key technology for liquid lithium usage, but has not been well investigated in dynamic conditions. Based on IFMIF (International Fusion Material Irradiation Facility)-EVEDA (Engineering Validation Engineering Design Activities), the nitrogen-trapping loop was designed and fabricated at The University of Tokyo. Lithium in the loop can be heated up to 600 °C and is circulated by a mechanical pump. The pump, which works in high temperature lithium, is newly developed as well. Nitrogen trapping material, such as the Fe–Ti alloy pebble, can be installed as a pebble bed column similar to that of the EVEDA nitrogen trap. In order to avoid contamination by air, all of the components are installed in a vacuum vessel or in a vacuum glove box.

The Engineering Validation and Engineering Design Activities (EVEDA) of the International Fusion Materials Irradiation Facility (IFMIF) have been started. As Japanese activities for the target system, the EVEDA Lithium (Li) Test Loop to simulate hydraulic and impurity conditions of the IFMIF Li loop is under design. The feasibility of the thermo-mechanical structure of the target assembly and the replaceable back-plate made of F82H and 316L stainless steel is a key research subject. Toward final validation at the EVEDA loop, diagnostics systems applicable to the high-speed free-surface Li flow and hot traps to control nitrogen and hydrogen in Li loop have been investigated. In the remote handling subject of target assemblies and the replaceable back-plates activated by irradiation up to 50 dpa/y, lip welds on 316L-316L by laser and dissimilar metal welds on F82H-316L are necessary. Water experiments and hydraulic/thermo-mechanical analyses of the back-plate are underway.

A key problem in the application of a supercritical carbon dioxide (CO 2 ) turbine cycle to a fast breeder reactor is the corrosion of structural materials brought about by supercritical CO 2 at high temperatures. In this study, long-term (8000 h) compatibility tests on candidate materials, two high-chromium martensitic steels (12Cr- and 9Cr-steels) and an austenitic stainless steel (316FR), were performed at 400–600 °C in supercritical CO 2 pressurized at 20 MPa, and corrosion allowances for the steels were proposed for application to preliminary reactor design. Although high temperature oxidation was measured in all steels, the behavior differed greatly. For martensitic steels, weight gain exhibited parabolic growth as exposure time increased at each temperature. Neither exfoliation of the oxide nor the breakage was observed during the 8000 h of exposure. The corrosion behavior was equivalent to that seen in supercritical CO 2 at 10 MPa, and it was confirmed that no effects of CO 2 pressure were present under the CO 2 turbine cycle operation conditions. Based on the results, corrosion allowances for temperature-dependant parabolic growth were proposed. For 316FR steel, weight gain was significantly lower than that of martensitic steels, with a maximum value of 6.2 g/m 2 at 600 °C for 8000 h. Since no dependency of temperature and immersion time on weight gain such as the martensitic steels was noted, corrosion allowances proportional to time was proposed. Estimated corrosion allowances for the martensitic and austenitic steels were 380 μm and 220 μm, respectively, for reactors, whose design life is rated at 60 years.

Two cases of spontaneous focal hepatic hyperplasia were observed in young female cynomolgus macaques (Macaca fascicularis). Grossly, a single raised nodule was observed in the left hepatic lobe. Histopathologically, the nodule compressed surrounding normal tissue; however, the hepatic cords within the nodule continued to those in the nor mal area except in part. Extensive fibrosis and absence of a normal hepatic triad were observed in the nodule. Thin fibrous septa radiating from the dense central stellate scarring and distended vessels were apparent in one animal. Hepatocytes in the nodule lacked cellular atypia, showed frequent PAS-positive eosinophilic inclusions in the cytoplasm and showed higher positive ratios for PCNA. The present cases resembled focal nodular hyperplasia reported in humans and a chimpanzee.

To clarify the morphological characteristics of the cynomolgus monkey immune system, we analyzed quantitative data on their lymphoid organs. Spleens, major lymph nodes and Peyer's patches were sampled from cynomolgus monkeys, and the lymphoid follicle and germinal center areas and percentages of CD3- and CD20-positive areas were calculated. All the organs analyzed showed large interindividual variations in the sizes of lymphoid follicles and germinal centers. Lymphoid follicle in the spleen, submandibular lymph nodes and Peyer's patches showed no marked difference in size. Germinal center size in the mesenteric lymph nodes and Peyer's patches were significantly smaller than those in the spleen. Areas containing T cells were largest in the lymph nodes, while those containing B cells were largest in the spleen and Peyer's patches. The mean size of the splenic lymphoid follicle in cynomolgus monkeys is larger than that in rats and similar to that in humans. Based on the large individual variation and the characteristics of lymphoid organs, it is important to use cynomolgus monkeys in standard toxicity studies. Taking advantage of the characteristics of each species enables reliable evaluation of the immunologic system in standard toxicity studies.

The long-term performance of 12Cr-2W ferritic/martensitic steel P122 and a 9Cr-2W ODS steel was tested in oxygen-containing flowing lead-bismuth eutectic (LBE) at 550 °C and a flow velocity of 2 m/s by means of exposure experiments in the CORRIDA loop. The target for the enrichment of dissolved oxygen was a concentration, c o , of 10 -6 mass%, corresponding to a lead oxide (PbO) activity of approximately 10- 3 . Owing to initial problems controlling c o , some of the exposed specimens experienced varying conditions, which allowed for investigating the influence of temporarily low c o (down to ∼10 -9 mass%), in addition to constantly high c o (averaging 1.6 x 10 -6 mass%). Maximum exposure times at constantly high c o were 10,000 and 20,000 h for P122 and the ODS steel, respectively. Under the testing conditions, both steels were affected by moderate oxidation resulting in the formation of a compact layer of a spinel-type oxide on the surface and a more or less pronounced internal oxidation zone. The thickness of the oxide scale was quantified and used for determining the material loss (metal recession). For c o ≈ 10- 6 mass%, logarithmic and power rate laws were fitted to the obtained data as a basis for predicting the metal recession at times exceeding the experimental exposure times. Temporarily lower c o proved to be beneficial for the performance of both steels, while, in the case of the ODS steel, excursions to higher c o should be prevented in order to achieve optimum oxidation resistance.

Corrosion resistances of oxide dispersion strengthened ferritic steels containing 3.5 wt% Al and 14–17 wt% Cr were examined. Experiments were performed in stagnant lead–bismuth eutectic (LBE) containing 10 −6 and 10 −8 wt% oxygen at 550 and 650 °C. The maximum exposure duration was 5000 h. Observations of the cross-sections of exposed samples obtained by scanning electron microscopy and Auger electron spectroscopy suggested that a very thin Al oxide layer was formed continuously. The materials containing 3.5 wt% Al exhibited good corrosion resistance despite being exposed to 5000 h of LBE containing 10 −6 wt% at 650 °C. Furthermore, a favourable influence of adding minor amount of Zr was detected after 5000 h exposure to LBE containing 10 −8 wt% oxygen at 650 °C.

A key problem in the application of a supercritical carbon dioxide (CO2) turbine cycle to a fast breeder reactor (FBR) is the corrosion of structural material by supercritical CO2 at high temperature. In this study, corrosion test of high-chromium martensitic steel (12Cr-steel) and FBR grade type 316 stainless steel (316FR), which are candidate materials for FBRs, were performed at 400-600°C in supercritical CO2 pressurized at 20MPa. Corrosion due to the high temperature oxidation in exposed surface was measured up to approximately 2000h in both steels. In the case of 12Cr-steel, the weight gain showed parabolic growth with exposure time at each temperature. The oxidation coefficient could be estimated by the Arrhenius function. The specimens were covered by two successive oxide layers, an Fe-Cr-O layer (inside) and an Fe-O layer (outside). A partial thin oxide diffusion layer appeared between the base metal and the Fe-Cr-O layer. The corrosion behavior was equivalent to that in supercritical CO2 at 10MPa, and no effects of CO2 pressure on oxidation were observed in this study. In the case of 316FR specimens, the weight gain was significantly lower than that of 12Cr-steel. Dependency of neither temperature nor exposed time on oxidation was not observed, and the value of all tested specimens was within 2g/m2. Nodule shape oxides which consisted of two structures, Fe-Cr-O and Fe-O were observed on the surface of the 316FR specimen. Carburizing, known as a factor in the occurrence of breakaway corrosion and/or the degradation of ductility, was observed on the surface of both steels.

An echo is one of the obstacles in halls and theatres. In order to suppress this undesirable echo, walls and ceilings have been often given absorptive surfaces which absorb sound energy or corrugated surfaces which provide wave diffusion. While it is not difficult to predict the degree of echo suppression effects in the case of absorptive surfaces, it is generally difficult to do that in the case of corrugated surfaces. In addition, if the surfaces have periodicity, unintended effects called coloration can distort tonal characteristics of the sound field. Thus, many acoustic designers would hesitate to employ this kind of periodic-type diffusers. However, there are some cases where it is necessary to suppress echoes without any energy loss. Periodic-type diffusers have the advantages of easy estimation of diffusion properties, simple method of design, and ready availability. In this study, a subjective experiment with simulated stimuli was carried out to clarify the echo suppression effect of the periodic-type diffusers from the viewpoint of reflected energy level. Although coloration interfered subjective judgments in some cases of the experiment, it is shown that the periodic-type diffusers have echo suppression effects if the coloration does not occur. This study is also devoted to discussion about causes and features of the coloration.

The corrosion resistances of ODS steels with 0–3.5 wt% Al and 13.7–17.3 wt% Cr, and a 12Cr steel were examined. The experiments were conducted at 550 and 650 °C for up to 3000 h in stagnant LBE containing 10 −6 and 10 −8 wt% oxygen for the ODS steels, and at 550 °C for up to 5000 h in that containing 10 −8 wt% oxygen for the 12Cr steel. Protective Al oxide scales were formed on the surfaces of the ODS steels with approximately 3.5 wt% Al and 13.7–17.3 wt% Cr. Addition of Al is very effective in improving the corrosion resistance of ODS steels. The ODS steel with 16 wt% Cr and no Al did not show any corrosion resistance except in LBE with 10 −6 wt% oxygen at 550 °C. The corrosion resistance may not be improved by solely increasing Cr concentration.

Recently, troponin T (TnT) and troponin I (TnI) have been reported as suitable biomarkers of myocardial injury for pre-clinical toxicity studies. The purpose of the present study was to investigate the characteristics of troponins as myocardial damage biomarkers in cynomolgus monkeys. Initially, tissue distribution of biomarkers was investigated in nine organs (including the heart, liver, and kidneys) collected from naive cynomolgus monkeys. The results showed that TnT and TnI were distributed specifically in the heart, and were not detected in other tissues. Secondly, changes in blood biomarker levels and histopathological changes in cardiac tissue were investigated following myocardial injury induced by concomitant administration of isoproterenol (ISO) and vasopressin (VASO). Compared with pre-dosing, TnT and TnI were markedly increased in the ISO + VASO groups, in which severe histopathological changes including necrosis and vacuolation of muscle fibers were observed. In order to investigate the relationship of biomarker levels with the severity of myocardial injury, Spearman's correlation coefficient was calculated between C(max) and AUC and necrosis and vacuolation scores in the heart. A high correlation between necrosis and vacuolation in the heart and TnT and TnI levels was noted. These results suggest that TnT and TnI possess high sensitivity and specificity for myocardial injury in cynomolgus monkeys, and are useful biomarkers for detection of drug-induced myocardial injury in cynomolgus monkeys.

症例 : 82歳, 女性. 現病歴 : 1998年に当院で血液透析を導入され他院にて通院透析中であった. 2006年4月17日より右眼瞼に発疹, 疼痛が出現し近医皮膚科で帯状疱疹と診断. 透析患者であるためアシクロビル軟膏で対処されるも疼痛我慢できず21日再診. 透析担当医と相談の上バラシクロビル1,000mg毎透析終了時で処方され内服. 翌日午前より歩行障害, 呂律障害, せん妄を認め当院救急外来受診. 血圧168/62mmHg, 体重30kg, 意識障害, せん妄を認めた. 頭部CT・MRI, 髄液検査, SPECT, 脳波などで脳血管障害, ヘルペス脳炎などを鑑別, 除外した上で, アシクロビル脳症と診断. 直ちにバラシクロビルを中止し血液透析を施行. 計4回の透析で症状は完全に消失し退院した. 結語 : バラシクロビルは透析患者推奨投与量においても小柄な高齢患者では神経症状を呈しうる. 体格, 年齢も考慮した上での薬物投与が必要と考えられた. 日本人透析患者への推奨投与量はこれまでの添付文書記載量よりさらに減量した量 (250mg/日) が妥当と考えられた.

Mycotoxin contamination of crops is a serious problem throughout the world because of its impact on human and animal health as well as economy. Inhibitors of mycotoxin production are useful not only for developing effective methods to prevent mycotoxin contamination, but also for investigating the molecular mechanisms of secondary metabolite production by fungi. We have been searching for mycotoxin production inhibitors among natural products and investigating their modes of action. In this article, we review aflatoxin and trichothecene production inhibitors, including our works on blasticidin S, methyl syringate, cyclo(l-Ala-l-Pro), respiration inhibitors, and precocene II.

Precocene II, a constituent of essential oils, shows antijuvenile hormone activity in insects and inhibits trichothecene production in fungi. We investigated the molecular mechanism by which precocene II inhibits trichothecene production in Fusarium graminearum, the main causal agent of Fusarium head blight and trichothecene contamination in grains. Voltage-dependent anion channel (VDAC), a mitochondrial outer membrane protein, was identified as the precocene II-binding protein by an affinity magnetic bead method. Precocene II increased the superoxide level in mitochondria as well as the amount of oxidized mitochondrial proteins. Ascorbic acid, glutathione, and α-tocopherol promoted trichothecene production by the fungus. These antioxidants compensated for the inhibitory activity of precocene II on trichothecene production. These results suggest that the binding of precocene II to VDAC may cause high superoxide levels in mitochondria, which leads to stopping of trichothecene production.

The behaviour of protective oxide layers on P122 steel and its welds and of ODS steel in liquid Pb 44.5 Bi 55.5 (LBE) is examined under conditions of changing temperatures and oxygen concentrations. P122 (12Cr) and its welded joints are exposed to LBE at 550 °C for 4000 h with oxygen concentrations of 10 −6 and 10 −8 wt% ( p (O 2 ) = 8.1 × 10 −23 bar and 5.2 × 10 −27 bar) which change every 800 h. It is found that like in case of constant oxygen concentration of 10 −6 wt% a protective spinel layer (Fe(Fe 1− x Cr x ) 2 O 4 ) was maintained on P122 and also on its welded joint. Two experiments with exposure times of 4800 h are conducted on ODS steel, both with temperatures changing from 550 to 650 °C and back every 800 h, one experiment with 10 −6 the other with 10 −8 wt% oxygen in LBE. Both experiments show strong local dissolution attack after 4800 h which is in agreement with the behaviour of ODS in LBE at a constant temperature of 650 °C. However, dissolution attack is less in LBE with 10 −8 wt% oxygen ( p (O 2 ) = 3.0 × 10 −25 bar).