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The development of photovoltaics (PV)-powered vehicles are expected to contribute to reduce CO2 emission of vehicles and create a clean energy society. This paper presents the impact of high-efficiency solar cell modules on reduction in CO2 emission, charging cost reduction for electric vehicles, and reducing storage capacity of PV-powered electric vehicles. In this paper, the effects of solar cell module efficiency upon driving distance of PV-powered vehicles are also shown. Especially, the potential of Si tandem solar cells for PV-powered vehicle applications is discussed. This paper presents that the III-V/Si 3-junction solar cell modules with an efficiency of more than 37% have the potential of longer driving distance of 30 km/day average and more than 50 km/day on a clear day compared to an average 16 km/day driving by vehicles powered by 20% efficiency Si solar cell modules.

Development of highly-efficient photovoltaic (PV) modules and expanding its application fields are significant for the further development of PV technologies and realization of innovative green energy infrastructure based on PV. Especially, development of solar-powered vehicles as a new application is highly desired and very important for this end. This paper presents the impact of PV cell/module conversion efficiency on reduction in CO2 emission and increase in driving range of the electric based vehicles. Our studies show that the utilization of a highly-efficient (higher than 30%) PV module enables the solar-powered vehicle to drive 30 km/day without charging in the case of light weight cars with electric mileage of 17 km/kWh under solar irradiation of 3.7 kWh/m2/day, which means that the majority of the family cars in Japan can run only by the sunlight without supplying fossil fuels. Thus, it is essential to develop high-efficiency as well as low-cost solar cells and modules for automotive applications. The analytical results developed by the authors for conversion efficiency potential of various solar cells for choosing candidates of the PV modules for automotive applications are shown. Then we overview the conversion efficiency potential and recent progress of various Si tandem solar cells, such as III-V/Si, II-VI/Si, chalcopyrite/Si, and perovskite/Si tandem solar cells. The III-V/Si tandem solar cells are expected to have a high potential for various applications because of its high conversion efficiency of larger than 36% for dual-junction and 42% for triple-junction solar cells under 1-sun AM1.5 G illumination, lightweight and low-cost potentials. The analysis shows that III-V based multi-junction and Si based tandem solar cells are considered to be promising candidates for the automotive application. Finally, we report recent results for our 28.2% efficiency and Sharp’s 33% mechanically stacked InGaP/GaAs/Si triple-junction solar cell. In addition, new approaches which are suitable for automotive applications by using III-V triple-junction, and static low concentrator PV modules are also presented.

Development of high-efficiency solar cell modules and new application fields such as PV (Photovoltaics)-powered vehicles are significant for the further development of PV and the creation of new clean energy infrastructure based on PV. In this paper, analytical results for impact of high-efficiency solar cell modules on increasing driving distance, reducing CO 2 emission and saving charging cost of electric vehicles by PV-powered vehicles. Because the Si tandem solar cells are expected to have significant potential for PV-powered vehicle applications, potentials of high-efficiency and driving distance are also analyzed. The III-V/Si 3-junction solar cell modules have potential of driving distance of 30 km/day average and more than 50 km/day on a clear day.

Aim A lack of known guidelines for the provision of extracorporeal cardiopulmonary resuscitation (ECPR) to patients with out‐of‐hospital cardiac arrest (OHCA) has led to variability in practice between hospitals even in the same country. Because variability in ECPR practice has not been completely examined, we aimed to describe the variability in ECPR practice in patients with OHCA from the emergency department (ED) to the intensive care units (ICU). Methods An anonymous online questionnaire to examine variability in ECPR practice was completed in January 2020 by 36 medical institutions who participated in the SAVE‐J II study. Institutional demographics, inclusion and exclusion criteria, initial resuscitation management, extracorporeal membrane oxygenation (ECMO) initiation, initial ECMO management, intra‐aortic balloon pumping/endotracheal intubation/management during coronary angiography, and computed tomography criteria were recorded. Results We received responses from all 36 institutions. Four institutions (11.1%) had a hybrid emergency room. Cardiovascular surgery was always involved throughout the entire ECMO process in only 14.7% of institutions; 60% of institutions had formal inclusion criteria and 50% had formal exclusion criteria. In two‐thirds of institutions, emergency physicians carried out cannulation. Catheterization room was the leading location of cannulation (48.6%) followed by ED (31.4%). The presence of formal exclusion criteria significantly increased with increasing ECPR volume (P for trend, Four institutions (11.1%) had a hybrid emergency room. Cardiovascular surgery was always involved throughout the entire extracorporeal membrane oxygenation process in only 14.7% of institutions. The presence of formal exclusion criteria significantly increased with increasing extracorporeal cardiopulmonary resuscitation volume.

Background: LncRNA PTCSC3 is a tumor suppressor in thyroid cancer, and its role in drug resistance of anaplastic thyroid cancer (ATC) to chemotherapy drug doxorubicin was investigated in this study. Methods: Expression of RNA and protein was analyzed by qRT-PCR and western blot, respectively. Flow cytometry was used to analyze the expression rate of CD133(+) cells. The endogenous expression of related genes was modulated by recombinant plasmids and cell transfection. Combination condition and interaction between PTCSC3 and STAT3 were determined by RIP and RNA pull-down assay, respectively. MTT assay was performed to detect cytotoxicity. Chromatin immunoprecipitation was conducted to identify interactions between STAT3 and DNA promoter of INO80. Results: LncRNA PTCSC3 was low-expressed in ATC tissues and cells. Over-expressed PTCSC3 inhibited the drug resistance of ATC to doxorubicin. PTCSC3 negatively regulated STAT3, and STAT3 promoted expression of INO80. PTCSC3 regulated INO80 through STAT3. PTCSC3 suppressed stem cells properties and drug resistance of ATC to doxorubicin. Conclusion: LncRNA PTCSC3 inhibits INO80 expression by negatively regulating STAT3, and thereby attenuating drug resistance of ATC to chemotherapy drug doxorubicin.

Fully non-inductive second (2nd) harmonic electron cyclotron (EC) plasma current ramp-up was demonstrated with a newlly developed 28 GHz system in the QUEST spherical tokamak. A high plasma current of 54 kA was non-inductively ramped up and sustained stably for 0.9 s with a 270 kW 28 GHz wave. A higher plasma current of 66 kA was also non-inductively achieved with a slow ramp-up of the vertical field. We have achieved a significantly higher plasma current than those achieved previously with the 2nd harmonic EC waves. This fully non-inductive 2nd harmonic EC plasma ramp-up method might be useful for future burning plasma devices and fusion reactors, in particular for operations at half magnetic field with the same EC heating equipment.

Electrical resistivity is a key durability indicator for evaluating the mass transport properties of cementitious materials particularly in partially-saturated states. In this work, the electrical resistivity of alkali-activated slag (AAS) with and without incorporation of sodium nitrite admixture, over a broad range of relative humidity (RH), is analyzed and compared to ordinary Portland cement (OPC) pastes. The van Genuchten equation and Archie equation are used to model the dependency of electrical resistivity of AAS on RH, degree of saturation, and pore structure parameters. The results show that at relatively high RH conditions (>58%), the electrical conductivity of AAS is significantly affected by the pore structure and conductivity of pore solution. At relatively low RH (

Metakaolin has been shown to play a significant role in the pore structure evolution of cementitious materials due to its high pozzolanic reactivity and small fineness. In this work, the early-age evolution of pore structure of moderate heat Portland cement (MHPC) pastes incorporating metakaolin is studied using an innovative impedance approach. Based on the fractal modeling, the pore structure parameters of MHPC blended with metakaolin of various mass percentages up to 20%, including porosity, pore size distribution, pore tortuosity and its fractal dimension, and mean and maximal pore diameters, are determined. The results from the impedance measurements show that the porosity of metakaolin-blended MHPC at both initial hydration and pozzolanic reaction stages increases with the hydration time, which is, respectively, attributed to the dissolution of cement and metakaolin grains. The maximal porosities and the saturation states of MHPC-metakaolin blended pastes occur concurrently due to the dissolution behavior of cement grains. It is concluded that metakaolin incorporation at the 10% replacement ratio is optimal in terms of pore structure refinement of blended cement pastes.

In the present RF-driven divertor plasma of QUEST, it has been observed that orbit-driven current flows in the open magnetic surfaces outside of the closed magnetic surfaces. To observe this phenomenon and the characteristics of the orbit-driven current, current density profiles have been calculated on two different equilibrium conditions. We calculated current density profiles from particle guiding center orbits both for the fundamental and the second harmonic resonances for the 8.2 GHz electron cyclotron current drive. From this calculation, hollow current density profiles have been obtained with significant characteristics on both conditions. Only positive current distribution has been observed in the open magnetic surfaces outside of the closed magnetic surfaces.

Poloidal and radial distributions of the hydrogen flux, both atomic and ion, to the plasma facing materials (PFMs) are measured with four fixed and one movable PdCu membrane probes in the QUEST spherical tokamak. Direct information about hydrogen retention in the areas far from main plasma-wall interaction is essential because the significant part of the global retention is due to atomic hydrogen. Incident hydrogen flux Γ inc is numerically reconstructed by fitting the experimentally measured hydrogen flux Γ p , permeated through the membrane. The sensitivity of the probe is improved when compared with other work which allows dynamic changes of the retention flux to be monitored, allowing detection of 10% of the Γ inc modulation, or ∼10 17 H m −2 s −1 .

A radiophotoluminescence (RPL) monitoring scope system was constructed to evaluate radioactive cesium contamination. RPL glass sheets were constructed by bonding RPL glass beads to a backing sheet. The RPL scope was constructed using an image intensifier and a CCD camera to detect RPL from the RPL glass sheet. A UV floodlight was also prepared as an excitation light source. The UV floodlight and an image intensifier were pulse-operated for high signal-to-noise RPL detection. In experiments, the RPL of X-ray irradiated glass sheets was measured with this present system. The RPL intensity, which is calculated from the brightness of obtained images, exhibits acceptable linearity to the absorbed dose. Another experiment showed that RPL can be detected at a distance of 10 m between the RPL glass sheets and the RPL detector.

Spontaneous toroidal rotation of the plasma is observed in the spherical tokamak QUEST with the help of electron cyclotron resonance (ECR) heating and without the use of any externally injected momentum. Several vertical magnetic field ( $B_{z}$ ) configurations with varying mirror ratio ( $M$ ) (a measure of field curvature) are applied and evolution of rotation is studied with the help of Doppler spectroscopy of bulk and impurity ions. Significant toroidal rotation ( $V_{\phi } \sim 6$ km/s) is initiated in the open magnetic field configuration during the initial plasma breakdown phase, which is later sustained ( $V_{\phi } \sim 20$ km/s) in a closed magnetic field configuration in steady state. Rotational velocity is primarily along the cocurrent direction and is found to be proportional to the $B_{z}$ strength and the resulting plasma current. High $M$ and $B_{z}$ are demonstrated to be the two specific external controls by which rotation can be initiated in the plasma. The rotation in open field lines is found to be initiated at the ECR layer in the slablike plasma, which is evolved to produce a sustained rotation in the natural divertor inboard poloidal field null equilibrium in QUEST.

The ascorbic acid (ASA) content of tomatoes is regulated by culture practices and environmental conditions such as light. However, in tomatoes, little is known about the direct effect of lighting conditions on ASA content in the absence of natural environmental fluctuations. The aim of this study was to determine the direct light regulation of ASA and dehydroascorbic acid (DHA) contents and the antioxidant system in tomato fruits grown in vitro using two different cultivars (high- and low-ASA cultivars), different light intensities [darkness, low light (∼249 μmol m−2 s−1), and high light (∼961 μmol m−2 s−1)], and different light spectra light emitting diodes (LEDs) under the same light intensity (226–249 μmol m−2 s−1): control (eight-peak LED), red LED light (peaks at 625 and 660 nm), and blue LED light (peaks at 420 and 450 nm). Results indicate that the effect of light on ASA and DHA content may be universal regardless of whether the cultivar is designated as a high- or low-ASA cultivar. ASA content was enhanced by an increase in light intensity and by blue (but not red) LED light. Our results also indicate that stimulation of the antioxidant system (ascorbate peroxidase and dehydroascorbate reductase activity) enhances ASA content under high light intensity, and underlying differences in mechanisms in response to blue and red LED light were observed. Therefore, we conclude that the direct light regulation of ASA content and the antioxidant system occurs in tomato fruits grown in vitro. In addition, our findings provide useful information for improving agricultural techniques to develop high-ASA tomatoes by controlling lighting conditions and by applying LED light.

In order to investigate the half-soaking galvanic accelerated corrosion and natural corrosion comparatively, an improved electrochemical model was established. Taking the diffusion of ions, potential distribution and polarization into consideration, the difference between two corrosion methods were essentially revealed. By changing the boundary conditions of the model, Finite Element Method (FEM) was applied to simulate corrosion potential distribution, ions concentration and current density both on the steel–concrete interface and within concrete. In natural corrosion, macrocell corrosion was coupled with microcell corrosion, and the anodic and cathodic current densities were self-balanced. To model the real corrosion under natural environment, the cathodic to anodic area ratio ( A c / A a ) of macrocell was assumed to be changing with the development of corrosion. In galvanic accelerated corrosion, the influence of external ions concentration on current density was considered, which eventually affected the distribution of rust layer of steel rebar. The simulation results agree well with the test data collected from literatures. A further discussion indicates that impressed current density significantly affects the time ratio of natural corrosion to galvanic accelerated corrosion, while the NaCl solution concentration shows no clear influence on time ratio. The bearing capacities of the corroded steel rebar under half-soaking method (HSM) and natural corrosion will show no clear difference, but the HSM method is not very appropriate for studying the corrosion cracking process of reinforced concrete.

Based on the electrochemical mechanism of steel corrosion, an improved electrochemical model was established to numerically simulate the corrosion of reinforcement in concrete under marine environment. The corrosion potential distribution and current density of corroded reinforcement were deduced from the corresponding micro-environments on the surface of steel bar, including oxygen, chloride ions, temperature and relative humidity. The equilibrium of gaseous oxygen and dissolved oxygen in pore solution was considered in the model. And the diffusion of invasion mediums in cement matrix and interfacial transition zone (ITZ) were also taken into account. The anode and cathode areas on the surface of steel bar was determined by the time-varying distribution of chloride ions rather than a fixed ratio to achieve the self-balance between macrocell and microcell corrosion. The simulation results agree well with the experimental data. The numerical analysis indicates that the growth of environmental chloride ions concentration will enhance the non-uniformity of chloride ions distribution, but does not contribute much to the increase of maximum rust layer thickness on steel surface. In the propagation stage of corrosion, oxygen concentration is a key factor in controlling corrosion reactions compared to chloride ions. Moreover, environment temperature has a positive effect on both the range of active areas on surface of steel rebar and rust layer thickness.

Plasma waves are important observational targets for scientific missions investigating space plasma phenomena. Conventional fast Fourier transform (FFT)-based spectrum plasma wave receivers have the disadvantages of a large size and a narrow dynamic range. This paper proposes a new type of FFT-based spectrum plasma wave receiver that overcomes the disadvantages of conventional receivers. The receiver measures and calculates the whole spectrum by dividing the observation frequency range into three bands: bands 1, 2, and 3, which span 1 Hz to 1 kHz, 1 to 10 kHz, and 10 to 100 kHz, respectively. To reduce the size of the receiver, its analog section was realized using application-specific integrated circuit (ASIC) technology, and an ASIC chip was successfully developed. The dimensions of the analog circuits were 4.21 mm × 1.16 mm. To confirm the performance of the ASIC, a test system for the receiver was developed using the ASIC, an analog-to-digital converter, and a personal computer. The frequency resolutions for bands 1, 2, and 3 were 3.2, 32, and 320 Hz, respectively, and the average time resolution was 384 ms. These frequency and time resolutions are superior to those of conventional FFT-based receivers.

Aim A challenge to the medical care of patients with rheumatoid arthritis (RA) is the management of the wide variety of information, including medication history and disease status, obtained from multiple sources to inform treatment decisions. To address this important clinical issue, we developed a data management system, based on smart device technology, and evaluated the benefit of this information to medical experts in helping them to form an impression of patients' health and disease, and treatment status before examination. Methods Fifty-seven patients with RA input relevant information about their condition and responses to a self-report health assessment questionnaire into a smart device template before their scheduled examination. The efficacy of the system was assessed as a decrease in examination time at each visit, and the correlation between the self-reported Multi-Dimensional Health Assessment Questionnaire and the 28-joint Disease Activity Score 28-joint count erythrocyte sedimentation rate (DAS28-ESR), which was used as a gold standard. Results Examination duration was reduced in most patients at each visit. During the study, there were no limitations for patients with poor eyesight or severe arthropathy in using the system. In fact, the majority of patients found the smart technology to be easier to use than hand-written questionnaires and health forms, regardless of age and disease activity. Conclusions Our findings support the use of smart technology to provide accurate patient-specific data and to streamline the process of medical care for patients with RA.

Effects of surface conditions on the plasma-driven permeation of hydrogen through a ferritic steel alloy F82H have been studied in a laboratory-scale plasma device: VEHICLE-1 and the medium-sized spherical tokamak: QUEST. Both of the surface contamination and area effects have been examined and discussed. Thick surface impurity film has been found to act as a second layer for diffusion and affect the permeation behavior in laboratory-scale and tokamak experiments. Hydrogen diffusion coefficient in the impurity layer has been estimated using the multi-layer diffusion model. A decrease in steady state permeation flux has been measured when increasing the plasma-facing surface area, which is in agreement with theoretical prediction.

At the Plasma Research Center at University of Tsukuba, development of megawatt gyrotrons is being performed as a collaborative electron cyclotron heating (ECH) study with some research organizatio...

After several experimental campaigns in the Kyushu University Experiment with Steady-state Spherical Tokamak (QUEST), the originally stainless steel plasma-facing wall (PFW) becomes completely covered with a deposited film composed of mixture materials, such as iron, chromium, carbon, and tungsten. In this work, an innovative colorimetry-based method was developed to measure the thickness of the deposited film on the actual QUEST wall. Because the optical constants of the deposited film on the PFW were position-dependent and the extinction coefficient k1 was about 1.0–2.0, which made the probing light not penetrate through some thick deposited films, the colorimetry method developed can only provide a rough value range of thickness of the metal-containing film deposited on the actual PFW in QUEST. However, the use of colorimetry is of great benefit to large-area inspections and to radioactive materials in future fusion devices that will be strictly prohibited from being taken out of the limited area.

In the present RF-driven plasma with a lot of high-energy electrons, there may be anisotropic plasma pressure, which makes the usual equilibrium analysis difficult, but the Cauchy condition surface method can reconstruct the plasma shape precisely regardless of the anisotropy. In addition, the plasma current effect in the open magnetic surfaces outside of the closed magnetic surfaces is considered in the RF-driven divertor plasma. In the reconstruction process, singular value (SV) decomposition is used and optimal criterion function for generalized cross validation is estimated concerning truncation or reduction of the small-SV components.

A 28~GHz system with a high-power gyrotron tube has been used for the QUEST spherical tokamak to form an over-dense plasma for electron Bernstein wave heating (EBWH) and current drive with an 8.2~GHz-wave. Non-inductive high-density plasma ramp-up experiments with dual-frequency (dual$-f$) electron cyclotron (EC) [ 8.2~GHz and 28~GHz ] waves were conducted. A spontaneous density jump (SDJ) to an over-dense state was observed as a bifurcation phenomenon in the dual$-f$ wave experiment. The over-dense plasma on the 8.2~GHz-wave was non-inductively ramped up to 25~kA, and was maintained for 0.4~s under stable plasma equilibrium after two such jumps in one shot. Heating to mildly energetic electrons and bulk electrons was observed even in the over-dense region. The electrostatic EBWH effect on the mildly energetic electrons in the over-dense region is assessed following a dispersion analysis of the 8.2 GHz-wave. The bulk electron heating effect observed is explained as heat exchange from mildly energetic electrons heated by the electrostatic EBWH wave. Remarkably, a high hard-X-ray-radiation temperature ~ 500~keV was also observed in tangential viewing for current-carrying electrons in the over-dense core region. Synergetic heating from the overlap of different 28~GHz EC harmonic resonances as well as higher harmonic heating is discussed for maintaining the highly energetic electrons in the over-dense core region. In addition, the SDJ process and mechanism are considered based on the discussion of the electron heating effects with the 8.2 GHz-wave.

It was found that the depth-directional distribution of radioactive cesium in soil could be roughly estimated with imaging plate strips, glass dosimeter fibers or a tube with built-in Si PIN photodiodes, which were put into the ground. Especially, it was confirmed that ordinary and inexpensive Si PIN photodiodes could be satisfactorily used as beta-ray detectors. The response of the photodiode to beta-rays and gamma-rays was examined by use of a Cs standard checking source. The pulse height distributions of the photodiode showed that it had sufficiently higher detection efficiency for beta-rays than for gamma-rays and also detection signals of beta-rays from radioactive cesium could be successfully discriminated from gamma-ray background and electromagnetic noises.

Diamond-like carbons (DLC) with different hardness of 47.1, 11.8 and 6.05 GPa were coated on SUJ2 rollers, and their tribological properties were investigated under boundary lubrication conditions in an additive-free mineral base oil at different testing oil temperatures of 24, 80 and 160 °C. The hardest DLC with 47.1 GPa showed the lowest friction coefficient and wear. From the results of the Raman analyses and spectroscopy ellipsometry, we found that the structure changed at oil temperature of thickness of 80 °C with the formation of a thick layer of 160 nm at the topmost sliding contact surface which provided the lowest friction coefficient of 0.03 in an additive-free mineral base oil.

Fiber-type radiophotoluminescence (RPL) glass dosimeters were satisfactorily made from reagent-grade powders of NaPO 3 , Al(PO 3 ) 3 and AgCl for the measurement of beta-radioactivity distribution in soil. The fiber-type glass dosimeters were covered with thin polyethylene film for the protection of the glass dosimeters against direct contact to soil particles. The RPL intensity of fiber-type glass dosimeters was successfully measured with a confocal microscope together with an ultraviolet pulsed laser. Depth-directional radioactive-cesium distribution in soil at Fukushima was well measured with the fiber-type RPL glass dosimeters and the confocal microscope system.

Aim To demonstrate the usefulness of the computed tomography (CT) fusion imaging for the evaluation of treatment effect of radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). Methods Eighty-five patients with 94 HCC with complete ablation judged on conventional side-by-side interpretation of pre-RFA and post-RFA CT at the time of RFA were included in this retrospective study. CT data was retrospectively used to create fusion images of pre-RFA and post-RFA CT using automatic rigid registration and manual correction referring to intrahepatic structures and hepatic contours around a tumor. Clinical factors including a minimal ablative margin (MAM) measured on fusion images were examined to prove risk factors for local tumor progression (LTP). Results LTP was observed in 13 (13.8%) tumors with a median follow up of 21.0 months (range, 2–75). The mean MAM on the fusion image was 1.4 ± 3.1 mm and 23 tumors (24.5%) were judged to be protruding from the ablation zone. Multivariate analysis revealed that protruding from the ablation zone was the only significant factor for LTP (hazard ratio, 7.09; 95% confidential interval, 2.26–22.3; P

The latest development achievements in the University of Tsukuba of over-1 MW power level gyrotrons required in present-day fusion devices, GAMMA 10, Large Helical Device (LHD), QUEST, Heliotron J and NSTX, are presented. The obtained maximum outputs are 1.9 MW for 0.1 s on the 77 GHz LHD tube and 1.2 MW for 1 ms on the 28 GHz GAMMA 10 one, which are new records in these frequency ranges. In long-pulse operation, 0.3 MW for 40 min at 77 GHz and 0.54 MW for 2 s at 28 GHz are achieved. A new programme of 154 GHz 1 MW development has started for high-density plasma heating in LHD. On the first 154 GHz tube, 1.0 MW for 1 s is achieved. As a next activity of the 28 GHz gyrotron, an over-1.5 MW gyrotron is designed and fabricated to study the multi-MW oscillation. The possibility of 0.4 MW continuous wave and 2 MW level output in operations of a few seconds, after the improvements of output window and mode converter, is shown. Moreover, a new design study of dual-frequency gyrotron at 28 and 35 GHz has started, which indicates the practicability of the multi-purpose gyrotron. © 2013 IAEA, Vienna.

Stockpiles of perfluoro-octane sulfonic acid (PFOS) containing aqueous film-forming foam (AFFF) have the potential to be emitted by leaching, spills, and during use in fire response and other processes. Several studies have discussed the high levels of stockpiled PFOS-containing AFFF and the risk they pose to the environment; however, there are large gaps in the amounts in Japan compared with other countries. For example, 300 tons are stockpiled in Canada, 2200–2600 tons in Switzerland, 1400 tons in Norway, and 19,000 tons in Japan from their reports for publication. The gap is considered to be a result of lack of surveys of several important sources. In this study, we revaluated the stockpile of AFFF in Japan to verify the reported value and identify the source of this gap based on information available in peer-reviewed papers, governmental reports, and business reports. The major reason for the gap between Japan and other countries was considered to be the survey of stockpiles in car-parking facilities, which accounted for 46.7% of the total amounts in Japan, but were not considered in other countries. These stockpiles indicate a high potential for accidental leaching or spilling of the AFFF by careless storage. Therefore, it is recommended that continual surveys of the AFFF stockpile in car-parking facilities be conducted in the rest of the world.

CCS (Cauchy Condition Surface) method is a numerical approach to reproduce plasma shape, which has good precision in conventional tokamaks. In order to apply it in plasma shape reproduction of ST (Spherical Tokamak), the calculation precision of the CCS method in a spherical tokamak CPD (Compact PWI experimental Device) (Bt = 0.25 T, R = 0.3 m, a = 0.2 m) has been analyzed. The precision was confirmed also in ST and decided to be applied to a spherical tokamak QUEST (Bt = 0.25 T, R = 0.68 m, a = 0.40 m).. In present stage from the magnetic measurement, it is known that the eddy current effect is large in QUEST experiment, and there are no special magnetic measurements for eddy current now, so some proper model should be selected to evaluate the eddy current effect. The eddy current density by not only CS (Center Solenoid) coil but also plasma current is calculated using EDDYCAL (JAEA). The eddy current magnitudes are taken as unknown variables and solved together with plasma shape reconstruction in ohmic discharge and ECCD (Electron Cyclotron Current Drive) discharge.

A permeation measuring system with a nickel membrane of 30 μm thickness was installed in a spherical tokamak QUEST. The membrane was located near the mid plane of the tokamak so that one side of the membrane was faced to the plasma. After the membrane was heated to 502 K, hydrogen plasma was discharged using 2.45 GHz RF system. The permeation flux through the membrane increased with a proper time-lag, that is, a significant plasma-driven permeation was observed. A numerical calculation of the diffusion equation under recombination boundary conditions was successfully conducted to simulate the transient permeation behavior. The recombination coefficients, estimated in a temperature range of 412–575 K, can be explained by a model of thermally activated processes. Stable operation of the permeation system indicates the suitability of this system for the measurements of atomic flux with known diffusivity and recombination coefficients.

In spectroscopic measurements of magnetically confined torus plasmas, the line-integrated emission along a viewing chord is usually observed. However, by utilizing the dependence of the magnitude of the Zeeman splitting on the emission location, a few localized emissions existing along the viewing chord can be separated. A detailed analysis of the Zeeman split spectral lineshapes then makes it possible to evaluate the local values of the magnetic field strength, population density, temperature, and flow velocity. We have introduced polarization spectroscopy to improve the accuracy in separating the overlapped spectra. The polarization resolved Hα, He I, and H2 Fulcher-α band spectra are measured in the TRIAM-1M tokamak, and the atomic and molecular dynamics are investigated. Further progress in the simultaneous measurements of the Balmer series and Fulcher-α band spectra in LHD, and extension to the CH Gerö band spectra, are briefly presented.

Plasma waves are an important target for satellite-based in situ observation to understand electromagnetic phenomena in space. Recent scientific satellites have carried fast Fourier transform (FFT)-based spectrum receivers; however, such receivers have a disadvantage because they use wideband analog parts. The new receiver overcomes the disadvantage by adding bandlimiting in the first stage of the analog part, and it covers the entire observation frequency range of each band by switching its cutoff frequency. In order to miniaturize circuit size, the new receiver comprises application-specific integrated circuits (ASICs) and a field-programmable gate array (FPGA). The ASIC chip includes the analog part of the receiver and the analog-to-digital converter, and the FPGA includes an FFT module and the controller of the receiver. The proposed spectrum receiver was successfully implemented with a size of 55 mm × 80 mm × 35 mm and a total power consumption of 948.3 mW. The time resolution of the receiver was 112 ms, and the frequency resolutions for frequency bands from 10 Hz to 1 kHz, from 1 kHz to 10 kHz, and from 10 kHz to 100 kHz were 13 Hz, 130 Hz, and 1.3 kHz, respectively. Overall, the developed receiver showed sufficient performance for plasma wave observation.

Particle retention and recycling in plasma fusion devices are generally associated with the diffusion of atomic hydrogen into the materials. The resulted permeation of atomic hydrogen is known as plasma driven permeation (PDP). This permeation may also be significant, even in the walls, which are not directly exposed to the plasma. Under similar conditions, the permeation flux (Γperm) of hydrogen through a 30 μm thick Ni membrane heated at 412–575 K has been measured in the spherical tokamak QUEST. Γperm is being measured during the scans of different operating parameters like RF power (PRF), chamber pressure (Pchamber), discharge widths (τdis) and vertical magnetic field (BZ). Simultaneously edge plasma density and spectral intensities of atomic (Balmer) lines and molecular (Fulcher) bands have been compared with the permeation measurements. A linear relationship has been established between the time integrated Γperm i.e. permeation fluence (Qperm) and the time integrated Hα intensity i.e. Hα fluence (Qα). Qperm also shows a strong relationship with the edge plasma density and various spectral fluences. The obtained results are discussed for exploring the applicability of the permeation probes in measuring the atomic flux near the first walls.

We have developed intense vacuum ultraviolet (VUV) radiation sources for advanced material processing, such as photochemical surface reactions and precise processing on a nanometer scale. We have constructed a new VUV laser system to generate sub-picosecond pulses at the wavelength of 126 nm. A seed VUV pulse was generated in Xe as the 7th harmonic of a 882-nm Ti:sapphire laser. The optimum conversion was achieved at the pressure of 1.2 Torr. The seed pulse will be amplified by the $\mathrm{Ar}_{2}^{*}$ media generated by an optical-field-induced ionization Ar plasma produced by the Ti:sapphire laser. We have obtained a gain coefficient of g=0.16 cm−1. Our developing system will provide VUV ultra-short pulses with sub-μJ energy at a repetition rate of 1 kHz.

Active particle control capabilities of a lithium-gettered rotating drum poloidal limiter have been demonstrated during 50 kW RF-current drive discharges in a compact spherical tokamak with the major and minor radii of 30 and 20 cm, respectively. The pulse length is typically ∼300 ms with a flat-top of ∼250 ms. The rotating limiter is in the shape of cylinder with the diameter and axial length of 15 and 12 cm, respectively. It has reproducibly been observed that, as soon as the rotating drum is gettered with lithium, hydrogen recycling measured with Hα spectroscopy decreases by a factor of ∼3 not only near the limiter but also in the center stack region. Also, the oxygen impurity level measured with O-II spectroscopy is reduced by a factor of ∼3. Meanwhile, the core electron temperature increases from around 7 eV to 20 eV along which the flat-top toroidal plasma current is found to nearly double even at the same vertical magnetic field. Comprehensive surface analysis has been conducted to investigate hydrogen and lithium distributions over the rotating drum after plasma exposure.

Fe–50 at.%Rh bulk alloys were irradiated with 10 MeV 127I, 60 MeV 136Xe and 200 MeV 136Xe ions at room temperature. Effects of the ion irradiation on magnetic properties were measured by using superconducting quantum interference device (SQUID). By comparing the results for higher energy (60 and 200 MeV) ion irradiation with that for lower energy (10 MeV) irradiation, we have obtained the linear relationship between the irradiation-induced magnetization and the deposited energy density though the elastic collisions. This relationship can be used for the quantitative modification of low temperature magnetism of Fe–50 at.%Rh alloy.

Fe–54at.%Rh thin films were irradiated with 10 MeV iodine ions at room temperature. Before and after the irradiations, the changes in magnetic properties and the lattice structure of the samples were studied by means of a SQUID magnetometer and X-ray diffraction. For the low fluence irradiation, the SQUID measurement at 20 K shows that the anti-ferromagnetic region of the thin film is changed into ferromagnetic region by the irradiation. As the film thickness is much smaller than the ion range, we can discuss the relationship between the density of energy deposited by ions and the change in magnetization quantitatively. For the high fluence irradiation, the magnetization of the film is strongly decreased by the irradiation, which can be explained as due to the change in lattice structure from B2 into A1 structure by the irradiation.

Experiments to study wall recycling behaviour have been performed in the small spherical tokamak compact plasma–wall interaction experimental device (CPD) from the viewpoint of global as well as local plasma wall interaction condition. Electron cyclotron resonance (ECR) plasma of typically ∼50 to 400 ms duration is produced using ∼40 to 80 kW RF power. In order to study the global wall recycling behaviour, pressure measurements are carried out just before and after the ECR plasma in the absence of any external pumping. The recycling behaviour is found to change from release to pumping beyond a certain level of pressure value which is again found to be a function of shot history. The real-time local wall behaviour is studied in similar RF plasma using a rotating tungsten limiter, actively coated with lithium. Measurement of H α light intensity in front of the rotating surface has indicated a clear reduction (∼10%) in the steady-state hydrogen recycling with continuous Li gettering of several minutes.

Neutral transport in the TRIAM-1M tokamak was analyzed using Monte Carlo simulation code (DEGAS). In the cases of low-density (~2×1012 cm-3) and high-density (~2×1013 cm-3) plasma discharges, the Hα intensity is localized around a neutral source, and in the toroidal direction, the 1/e decay lengths of the Hα intensity in two kinds of discharge differ by a factor of 1.5 to 2. By using a cylindrical mesh model for the DEGAS code, the simulated Hα intensities properly explained the experimental results. A detailed analysis of the simulation results revealed that the Hα profile is significantly affected by the geometric structure of the plasma facing component and the parameters of plasma and neutral particles.

Fully non-inductive lower hybrid current drive (LHCD) plasmas have been achieved in TRIAM-1M and HT-7 superconducting tokamaks, but the current control in toroidal plasma was performed in different way during their steady-state operation (SSO). In HT-7, the plasma current was controlled mainly by the ohmic field, and partially by LHCD through ohmic transformer magnetic flux feedback control. In TRIAM-1M, the plasma current was controlled by lower hybrid wave (LHW) power directly according to a simple simulation model.

Superconducting tokamak TRIAM-1M has just ceased its operation in December 2005. However, in order to develop the systematic study on plasma–wall interaction in long duration discharges in the TRIAM-1M tokamak, spherical tokamak QUEST is under construction. To fulfill the mission of QUEST under a small group of the university in collaboration with other group, control and interlock system must be designed appropriately. Hence, a spherical tokamak CPD was constructed and the experiment is carried out for preparation of QUEST. The control and interlock system for QUEST is tested and developed during the experiment in the CPD.

On tokamak devices, an induction electric field induced by poloidal field (PF) coils plays a role to produce initial plasma. On a DIII-D tokamak, the required induction electric field for plasma breakdown agrees well with theoretical predictions based on the Townsend avalanche theory. According to the Townsend avalanche theory, the minimum induction electric field for plasma breakdown depends on neutral gas pressure and connection length. For stable plasma breakdown, a sufficiently large induction electric field is required. However, in the case of spherical tokamaks without electric insulation in the toroidal direction, the effect of eddy currents flowing in the toroidal direction should be considered in evaluating a feasible induction electric field because this effect suppresses the generation of an induction electric field. On a QUEST spherical tokamak, the possibility of Townsend avalanche breakdown is studied by evaluating the connection length and achievable induction electric field. The connection length is greater than 100 m in the case where a null point is set to be R=0.56 m with a CS coil current of 2.0 kA and a PF26 coil current of 0.4 kA. Moreover, the induction electric field is about 1.5 V at this point including the effect of eddy currents. With these values, the initial plasma production by the induction electric field is sufficiently possible on QUEST.

症例は79歳男性．他院にて，平成10年より洞不全症候群（Rubenstein I型）に対しDDDR型ペースメーカーの加療を受けている．同時期よりC型慢性肝炎を指摘され，平成15年肝S7の11mm大の肝細胞癌に対しエタノール注入療法が施行された．平成17年S7に再発を疑われ肝動脈塞栓療法施行されるも，平成18年4月S7に30mm大の再発肝細胞癌を指摘されたため，加療目的にて当科紹介入院となった．basic rate-70ppmの設定下ではall pacingの状態であったが，basic rateを50ppm以下とすることで自己心拍が確認できた．したがって，AAI mode-basic rate-45ppmの設定下で，ラジオ波焼灼療法（RFA）を施行した．LeVeen Needle（3cm）使用し，1/4展開，出力20Wより焼灼開始，全展開最大出力60Wまで24分間段階的に焼灼した．術中，ペースメーカー不全は生じず術後にも正常に作動した．腹部造影CTにて，良好な焼灼範囲を確認し退院となった．肝細胞患者の高齢化が進行してきており，今後ペースメーカー管理下の患者も増加すると推定される．このような患者で，局所治療の適応がある場合には，厳重なリスク管理を行う事により，RFAの適応はさらに拡大できる可能性がある．

Combined experiments with lower hybrid (LH) waves (LHWs) and electron cyclotron (EC) waves (ECWs) have been performed to study counter (ctr) current drive (CD) (ctr-CD) in LHCD plasma. Although the...