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Local distribution of orientation relationship between austenite and martensite is quantitatively examined using lath martensite in an ultra-low-carbon steel. Orientation relationship is systematically deviated between near Greninger–Troiano and Nishiyama–Wasserman orientation relationships around variant boundaries of the smallest misorientation pair, which is observed as the most frequent variant pair in the steel. Misorientation between this variant pair is decreased at some boundaries of the pair. Formation mechanism of the pair is discussed using the observed boundary characters. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Highlights • A novel degradation diagnosis method for photovoltaic modules was proposed. • The proposed method utilizes xenon flash lighting system and detector capacitor. • The proposed method includes sensing process of module temperature. • The proposed method can evaluate increase of module internal series resistance. • The proposed method can find out modules with broken bypass diode. Abstract This paper proposes a novel and unique degradation diagnosis method for photovoltaic modules employing a xenon flash lighting system and a capacitor for degradation detection connected to the module output. The xenon flash lighting system is not only compact and lightweight but also small in power consumption and can be lit by batteries. Therefore, the portability of the lighting system is satisfactory, and the proposed diagnosis method is expected to be relatively easily applicable to outdoor photovoltaic power plants. In addition, since the lighting system can provide artificial and precisely controlled intense flash light to the module and this proposed method includes a sensing process of the module temperature, this proposed method can, in principle, evaluate the internal series resistance and determine accurate degradation level independent of the weather and temperature conditions. The authors carried out the numerical simulations and successfully made clear that the theoretically unavoidable measurement error of the internal series resistance is only 2% less than its variation width, confirming the validity of the basic ideas of the proposed degradation diagnosis method. The authors then performed the demonstration test experiments using a prototype experimental apparatus and investigated its practicability for real PV modules, successfully confirming that the same accuracy as expected through the simulations can be achieved also through the experiments. [ABSTRACT FROM AUTHOR]

We have numerically calculated transport characteristics on a Miller-Abraham network in a non-linear regime by solving the Kirchhoff's current law at each site. Assuming the Mott model, we obtained the relation between current density and electric field, J ∝ exp ( γ E ) , which has often been observed in low-mobility materials and whose mechanism has been a source of controversy for over half a century. Our numerical calculation makes it possible to analyze the energy configuration of relevant hopping sites and visualize percolation networks. Following the percolation theory proposed by Shklovskii [Shklovskii, Sov. Phys. Semicond. 10 , 855 (1976)], we show that the main mechanism of the field dependence is the replacement of dominating resistances accompanied by the geometrical evolution of the percolation networks. Our calculation is so general that it can be applied to hopping transport in a variety of systems. [ABSTRACT FROM AUTHOR]

This study addresses the hypothesis that SIRT1 upregulation prior to cryopreservation helps in recuperation from cryoinjury and improves the embryo quality. Bovine blastocysts were produced in vitro , and at Day 6 or 7 after fertilization, the blastocysts were cultured with 0 or 1 μM resveratrol for 6 or 24 h. This short duration of resveratrol treatment did not affect the embryo development or the grade of the blastocysts. However, both the durations of resveratrol treatment (6 h or 24 h) significantly increased the expression levels of SIRT1. When embryos pre-treated with resveratrol (0 or 1 μM) were cryopreserved and subsequently thawed, the hatching rates following 48 h of incubation were significantly higher for the resveratrol-treated embryos than for vehicle-treated embryos. Moreover, the resveratrol pretreatment significantly increased the copy number of mitochondrial DNA in the embryos, irrespective of the treatment durations. The in vitro -produced embryos at 6 days of insemination and the in vivo -developed embryos, which were collected from the donor cows at 6.5 days of insemination, were treated with resveratrol for 6 or 24 h prior to cryopreservation, respectively. The resveratrol pretreatment (for 6 or 24 h) resulted in high conception rate after thawing and transfer to the recipients, in both the in vivo and in vitro -produced embryos. In conclusion, our results suggest that pretreatment of bovine embryos with resveratrol improves the quality of embryos after cryopreservation and thawing probably through mitochondrial synthesis. [ABSTRACT FROM AUTHOR]

Background Hydrogen (H 2 ) and carbon monoxide (CO) gas are both reported to reduce reactive oxygen species and alleviate tissue ischemia-reperfusion (I-R) injury. The present study was conducted to evaluate the effects of a mixture of H 2 gas and CO gas (dual gas) in comparison with hydrogen gas (H 2 : 2%) alone on I-R renal injury (composition of dual gas; N 2 : 77.8%; O 2 : 20.9%; H 2 : 1.30%; CO: 250 parts per million). Methods Adult male Sprague-Dawley rats (body weight 250–280 g) were divided into 5 groups: (1) sham operation control, (2) dual gas inhalation (dual treatment) without I-R treatment, (3) I-R renal injury, (4) H 2 gas alone inhalation (H 2 treatment) with I-R renal injury, and (5) dual treatment with I-R renal injury. I-R renal injury was induced by clamping the left renal artery and vein for 45 minutes followed by reperfusion, and then contralateral nephrectomy was performed 2 weeks later. Renal function was markedly decreased at 24 hours after reperfusion, and thereafter the effects of dual gas were assessed by histologic examination and determination of the superoxide radical, together with functional and molecular analyses. Results Pathologic examination of the kidney of I-R rats revealed severe renal damage. Importantly, cytoprotective effects of the dual treatment in comparison with H 2 treatment and I-R renal injury were observed in terms of superoxide radical scavenging activity and histochemical features. Rats given dual treatment and I-R renal injury showed significant decreases in blood urea nitrogen. Increased expression of several inflammatory cytokines (tumor necrosis factor-α, interleukin-6, intracellular adhesion molecule-1, nuclear factor-κB, hypoxia inducible factor-1α, and heme oxygenase-1) was attenuated by the dual treatment. Conclusions Dual gas inhalation decreases oxidative stress and markedly improves I-R-induced renal injury. [ABSTRACT FROM AUTHOR]

Abstract: In the present paper, we will introduce the synthesis and application of carbon nanotubes as filler for nanocomposite materials. Physical and chemical properties such as mechanical strength, thermal and electrical conductivity, chemical stability, density and affinity with the matrix vary a lot among different types of carbon nanotubes. We first will overview the main component of nanocomposite, carbon nanotube and its synthesis and purification, and introduce some of the nanocomposites and its applications that we have taken part in the development. [Copyright &y& Elsevier]

Abstract: A polycrystalline solar cell with several grains was investigated by the laser-SQUID (Superconducting QUantum Interference Device) microscope. The laser-SQUID microscopy detects the magnetic field generated by a photo-induced current. This technique enables nondestructive and noncontact evaluation of semiconductor samples. A needle made of high permeability material was used to transmit the magnetic field near the sample to the SQUID. The needle and the SQUID were shifted in the x- and y-directions from the center of a laser spot. The laser-SQUID microscope images varied with needle position. This indicated the possibility of current estimation using a laser-SQUID microscope. In this study the sample was also evaluated using Laser Beam Induced Current (LBIC) which is widely used for evaluation of the conversion efficiency distribution of solar cells. The laser-SQUID microscope image was compared with the LBIC image and was found to be similar. This result showed that laser-SQUID microscopy can be used for the electrical evaluation of solar cells without contact, and furthermore has the possibility of estimation of the photocurrent direction. [Copyright &y& Elsevier]

Abstract: The permeation behavior of tritium through pure iron into the gas containing water vapor has been studied. It was found that the permeation rate of tritium was almost the same as that with no water vapor, and the major chemical form of tritium was HTO. It was also found that the permeation rate was decreased to ∼1/10 of the above value by plated with gold, and the major chemical form was HT. As for the behavior of high concentration tritium water, it was observed that the formation of the oxidized layer was prevented by the presence of tritium in water (0.23GBq/cc). A set of data for an advanced chemical exchange column has been obtained as R&D on the tritiated water processing. The packing and catalyst were uniformly mixed into the advanced column. It has been proved that there was possibility that the advanced column has a large separation factor in comparison with the ordinary columns, where the packing and catalyst were alternately packed. Tritium durability tests were also carried out for the electrolysis cell of the chemical exchange column. The ion conductivity of the main material of the cell (Nafion) was hardly decreased even in the case of 1600kGy irradiation by gamma ray. [Copyright &y& Elsevier]

Abstract: Depth profiles of deuterium trapped in graphite tiles not exposed to hydrogen discharges just before air ventilation of JT-60U were determined based on the D(3He,p)4He resonant nuclear reaction analysis. The samples were taken from the W-shaped divertor. The maximum depth of analysis is about 1.4×1024 carbon atoms/m2, corresponding to a linear depth of 16μm for the density of 1.7×103 kg/m3. The highest concentration (19at.%) was found at the surface of the inner divertor area, which was significantly higher than that exposed to H discharges at the same location. However in the deeper region, the deuterium concentrations without H discharges were lower than those with H discharges in 3 of 4 samples. These results indicate that hydrogen discharges can remove deuterium trapped only in the shallow region. [Copyright &y& Elsevier]

Abstract: Gap junctional communication plays an important role in various models of brain pathology, but the changes of gap junctions in Parkinsonism are still not understood. In this study, we show that a major gap junctional protein, connexin43 (Cx43), in astrocytes is enhanced both in a rat Parkinson''s disease (PD) model induced with rotenone, a widely used pesticide that inhibits mitochondrial complex I, and in vitro in cultured astrocytes stimulated with rotenone. Enhancement of Cx43 protein levels in rotenone-treated cultured astrocytes occurred in parallel with an increase in gap junctional intercellular communication, but was not accompanied with an increase in Cx43 mRNA levels. Furthermore, the rotenone-induced increase of Cx43 protein levels both in vitro and in vivo was associated with increased levels of phosphorylated Cx43, which is required for gap junctional intercellular communication. In our rat PD model, phosphorylated Cx43 was selectively enhanced in the basal ganglia regions, which contain DA neurons or their terminal areas. The increase of Cx43 levels was lower in the substantia nigra pars compacta and the striatum than in the substantia nigra pars reticulata and the globus pallidus. Our findings indicate that modulation of Cx43 protein, and consequently gap junctional cellular communication, in astrocytes may play an important role in PD pathology. [Copyright &y& Elsevier]

Abstract: In an ITER facility, about 3kg of tritium will be stored in about 50 hydride beds. The safe design and operation of tritium storage beds will be one of the most important points for enhancing overall safety in the facility. In the Tritium Process Laboratory at the Japan Atomic Energy Agency, many tritium storage beds with zirconium–cobalt (ZrCo) and uranium (U) have been used with/without self-accountancy measures, and 20 years of safe handling experience has been accumulated. From this experience, the key issues to be considered for the safety design are the effects of tritium decay, such as decay heat transfer and 3He behavior, which can cause an increase in temperature and pressure in the tritide vessel, along with the normal protection against over-temperature, over-pressure and leaks in the metal-hydride bed. Concerning the safety operation, the key issues are the hydrogenation–dehydrogenation cycle sequence under the requirements of the storage system and the emergency action, such as rapid hydrogen recovery and loss of normal cooling function. [Copyright &y& Elsevier]

Abstract: At Tritium Process Laboratory (TPL) of Japan Atomic Energy Agency (JAEA), tritium technologies for a fusion reactor have been carried out up to date. The design studies of Air Detrtiation and Vent Detritiation System (ADS/VDS) of ITER have been carried out in JAEA as a contribution of Japan to ITER. For the tritium processing technologies, our efforts have been focused on the R&D of the tritium recovery system of ITER test blanket system. A ceramic proton conductor has been studied as an advanced blanket system. A series of fundamental studies on tritium safety technologies for ITER and for fusion DEMO plants has also been carried out. The main R&D activities in this field are the tritium behavior in a confinement and its barrier materials, monitoring, accountancy, detritiation and decontamination, etc. Especially, for the fundamental studies for a DEMO plants, a part of the studies will be carries out a new facility at Rokkasho in Aomori in the Broader Approach (BA) program in coming 10 years. For this purpose, a design study of the facility at Rokkasho has first been started. [Copyright &y& Elsevier]

Abstract: There is increasing demand for oxide-dispersion-strengthened ferritic alloys that possess both high-temperature strength and irradiation resistance. Improvement of the high-temperature properties requires an understanding of the operative deformation mechanisms. In this study, the microstructures and creep properties of the oxide-dispersion-strengthened alloy 14YWT have been evaluated as a function of annealing at 1000°C for 1 hour up to 32 days. The ultra-fine initial grain size (approx. 100nm) is stable after the shortest annealing time, and even after subsequent creep at 800°C. Longer annealing periods lead to anomalous grain growth that is further enhanced following creep. Remarkably, the minimum creep rate is relatively insensitive to this dramatic grain-coarsening. The creep strength is attributed to highly stable, Ti-rich nanoclusters that appear to pin the initial primary grains, and present strong obstacles to dislocation motion in the large, anomalously grown grains. [Copyright &y& Elsevier]

Abstract: We have successfully grown high-purity and -quality PbI2 single crystals by the vertical Bridgman method. The rocking curves of four-crystal X-ray diffraction (XRD) show 120arcsec in full-width at half-maximum (FWHM). The photoluminescence (PL) spectra at 7.8K show the resolved intensive exciton emission line and the weak DAP emission band. The deep-level emissions are not observed. The measurement of the electrical and radiographic properties show that Leadiodide (PbI2) single crystal has a resistivity of 5×1010 Ωcm and imager lag is 8s, respectively. In order to improve the controllability of crystal growth, PbI2 single crystals were also grown from a lead (Pb) excess PbI2 source. The experimental results show very good reproducibility. In addition, the growth models of crystal are proposed, and the growth mechanism is discussed. [Copyright &y& Elsevier]

Abstract: Defects related to oxygen and other impurities in piezoelectric langasite (La3Ga5SiO14; LGS) single crystals grown by the vertical Bridgman (VB) method was investigated. The resistivity of an LGS crystal grown in an Ar atmosphere was about one-order higher than that grown in air. However, after annealing in air it decreased to the same level as that of LGS crystal grown in air. The results of optical transmission spectra showed a broad adsorption peak around 500nm, corresponding to 2.5eV of energy level, in LGS crystals grown in air and grown in an Ar atmosphere. Since VB-grown LGS crystal was p-type, excess interstitial oxygen atoms, not oxygen vacancies, operate as an acceptor in the VB-LGS crystal. [Copyright &y& Elsevier]

Abstract: The possibility of reducing the concentration of 14C produced in irradiation of reduced activation ferritic steels (RAFS) intended as structural materials in first wall and blanket of fusion power plants was investigated. During RAFS irradiation 14C is mainly produced from the more abundant of the two isotopes of nitrogen present in the steel, namely 14N. The method proposed consists in increasing the enrichment of the other isotope (15N). One-dimension transport calculations show that for a typical DEMO blanket configuration an 15N enrichment from the natural value (0.37%) to 95% was sufficient to keep the end of life 14C concentration in the RAFS below the limit (3.7×107 Bq/kg) fixed by the Japanese Nuclear Safety Commission for qualifying it as a low level material (LLM) which can be disposed by shallow land burial. [Copyright &y& Elsevier]

Quantitative PCR can be an effective method for identifying the bacteria causing mastitis. However, PCR detection is hampered by the presence of inflammatory somatic cells. To eliminate this problem, we attempted to establish methods that allow the effective separation of bacterial cells from somatic cells in mastitis milk with amino-silica. Somatic cells and Staphylococcus aureus cells have different sizes, surface structures, and overall electrical charges; therefore, their adsorption and desorption behavior on amino-silica was also different. We found that although amino-silica could efficiently adsorb both somatic cells and Staph. aureus, somatic cells were adsorbed much more strongly than bacterial cells. We identified conditions under which most of the somatic cells adsorbed and only Staph. aureus desorbed from amino-silica upon addition of a desorption solution. We demonstrated that this procedure effectively eliminated somatic cells in heavily contaminated milk samples, which resulted in improved clarity of the PCR band. These results indicate that pretreatment of the samples with amino-silica made the PCR-based strategy for identifying and quantifying disease-causing bacteria applicable for all milk samples. [ABSTRACT FROM AUTHOR]

Abstract: H and D retention characteristics in the near top surface of the JT-60U plasma facing carbon tiles were investigated by means of elastic recoil detection analysis. From the result, H was dominantly retained within 1μm depth because of the H discharges for the wall cleaning carried out before the removal of sample tiles. (H+D)/C ratios were small: it was ∼0.07 at a maximum in the divertor samples except for the deposition on the dome outer wing tile which was ∼0.13, and it was ∼0.15 at a maximum in the first wall samples. The hydrogen concentration in the redeposited carbon layers is strongly influenced by the temperature. Consequently, (H+D)/C ratios at the observed low level are a result of the operation of JT-60U at wall temperatures of 300°C or higher. [Copyright &y& Elsevier]

Abstract: Deuterium depth profiles in graphite tiles of JT-60U have been determined by means of the D(3He,p)4He nuclear reaction. Tiles with net carbon deposition showed high deuterium retention. A D/C ratio of 0.07 was found in the outer dome wing tile. In the inner divertor tile covered with a thick deposition layer, the depth profile shows a broad peak in a deep region. This indicates that deuterium trapped in the shallow region can be replaced by hydrogen with hydrogen discharges due to isotope exchange, while deuterium trapped in the deeper region can not. Deuterium in the redeposited layers can be more easily removed than that in the substrate. The deuterium concentration in the outer divertor target tile was very low (D/C<0.003). The highest D/C ratio, 0.09, was found in the upper region of the first wall. [Copyright &y& Elsevier]

Abstract: The possibility of tritium self-sufficiency in a low aspect ratio (low-A) tokamak reactor with the outboard blanket only has been studied to simplify the inboard structure located in a high magnetic field. The tritium breeding ratio (TBR) of the outboard blanket increases by applying a neutron multiplier such as lead and beryllium to the inboard reflector. The effect in local TBR of a 40cm thick inboard reflector of lead is about 40% that of the inboard breeding blanket. The local TBR of a reactor with both the lead inboard reflector and outboard blanket using a Li2O breeder and a beryllium multiplier can be larger than 1.35 for aspect ratios less than 2.9. The local TBR of 1.35 satisfies the net TBR requirement of 1.05 where there is 78% coverage of the breeding zone over the total plasma-facing surface area. The result indicates there is a design solution achieving tritium self-sufficiency even in a low-A tokamak reactor with the outboard breeding blanket only, using an appropriate inboard reflector. Be12Ti and Li2TiO3 are recommended from the viewpoint of safety. In the combination, the aspect ratio is required to be less than 1.35 to achieve local TBR of 1.35. [Copyright &y& Elsevier]

Abstract: In a fusion reactor, high-level tritiated water of more than one PBq/m3 will be generated and stored in various areas. The high-level tritiated water decomposes by itself and generates mainly hydrogen, becoming tritiated hydrogen peroxide water. In order to summarize safety requirements for long-term storage of high-level tritiated water, the characteristics, such as effective G-values of hydrogen and hydrogen peroxide, pH and Oxidation–Reduction Potential (ORP), have been investigated by storing tritiated water from 5TBq/m3 to 2EBq/m3 for 5 years. Because the effective G-value of hydrogen increases with decreasing tritium concentration, the storage tank for a wider range of tritium concentrations requires not only depression but, also, adequate processing of the cover gases. High-level tritiated water of more than 1PBq/m3 was acid and in some cases was in a corrosive condition; these characteristics have been maintained for 5 years. Therefore, the ORP–pH situation should be monitored periodically to avoid the corrosive condition. [Copyright &y& Elsevier]

Abstract: In order to establish the effective surface decontamination methods for the ITER construction materials, the so-called ‘soaking’ effect is important and more systematic data of tritium sorption and desorption for various materials are required under actually conditions. In order to obtain and summarize data on the amount of sorbed tritium on the various materials such as stainless steel (SS), acrylic resin, and epoxy paint, a series of tritiated water vapor exposure experiments have been carried out as a function of time. The materials were almost saturated with tritium within a period from several weeks to 1 month, and it was larger in the order of epoxy paint>acrylic resin=butyl rubber>SS304. The sorption rate and subsequent desorption rate for various materials were evaluated. [Copyright &y& Elsevier]

Abstract: Neutron transport calculations have been performed to evaluate the capability of metal hydrides and borohydrides as advanced shielding materials. Some hydrides are characterized by considerably higher hydrogen content than polyethylene and solid hydrogen. The hydrogen-rich hydrides show superior neutron shielding capability compared to the conventional materials. A one-dimensional cylindrical model was used to do the neutron transport calculation. The shields are located at the inboard and outboard sides, and they are 30 and 70cm in radial thickness, respectively. Mg(BH4)2, TiH2 and ZrH2 can reduce the thickness of the outboard shield by 23, 20 and 19%, respectively, compared to the combination of steel and water. Mixing Mg(BH4)2 with F82H produces large effects in the gamma-ray shielding. In the mixing ratio of 0.5, the gamma-ray flux was 300 times smaller than that of pure Mg(BH4)2, even though the fast neutron flux is 13% larger than that of pure Mg(BH4)2. In the neutron spectrum for Mg(BH4)2, the neutron flux in the energy range of less than 100eV drastically reduced as compared to those of other materials, due to the effect of boron. [Copyright &y& Elsevier]

Abstract: Deuterium concentrations and depth profiles in plasma-facing graphite tiles used in the divertor of JAERI Tokamak-60 Upgrade (JT-60U) were investigated by nuclear reaction analysis (NRA). The highest deuterium concentration of D/12C of 0.053 was found in the outer dome wing tile, where the deuterium accumulated probably through the deuterium–carbon co-deposition. In the outer and inner divertor target tiles, the D/12C data were lower than 0.006. Additionally, the maximum (H+D)/12C in the dome top tile was estimated to be 0.023 from the results of NRA and secondary ion mass spectroscopy (SIMS). Orbit following Monte-Carlo (OFMC) simulation showed energetic deuterons caused by neutral beam injections (NBI) were implanted into the dome region with high heat flux. Furthermore, the surface temperature and conditions such as deposition and erosion significantly influenced the accumulation process of deuterium. The deuterium depth profile, scanning electron microscope (SEM) observation and OFMC simulation indicated the deuterium was considered to accumulate through three processes: the deuterium–carbon co-deposition, the implantation of energetic deuterons and the deuterium diffusion into the bulk. [Copyright &y& Elsevier]

Abstract: An HTS SQUID probe microscope has been developed using a high-permeability needle to enable high spatial resolution measurement of samples in air even at room temperature. Image processing techniques have also been developed to improve the magnetic field images obtained from the microscope. Artifacts in the data occur due to electromagnetic interference from electric power lines, line drift and flux trapping. The electromagnetic interference could successfully be removed by eliminating the noise peaks from the power spectrum of fast Fourier transforms of line scans of the image. The drift between lines was removed by interpolating the mean field value of each scan line. Artifacts in line scans occurring due to flux trapping or unexpected noise were removed by the detection of a sharp drift and interpolation using the line data of neighboring lines. Highly detailed magnetic field images were obtained from the HTS SQUID probe microscope by the application of these image processing techniques. [Copyright &y& Elsevier]

Abstract: We numerically calculate total AC losses in a single Bi-2223 tape carrying a transport current in an external magnetic field parallel or perpendicular to the tape face. We also carry out the calculations for two models of three-strand parallel conductor. One is without transposition, and the other is with optimum transposition so that the branch current in each strand becomes equal. It is confirmed the total AC losses fairly increase with the simultaneous application of transport current. It is also found that in the perpendicular field the total losses are scarcely dependent on transposition but on the number of strands in the smaller field amplitude. In the parallel field, the effect of the number of strands on the total AC losses is notable as well as transposition. [Copyright &y& Elsevier]

Abstract: AC losses are numerically evaluated in thin superconducting tapes exposed to an external magnetic field perpendicular to their broad face under the assumption of the critical state model including the field dependence of a critical current density. When the thickness of tape is much smaller than the width, the electromagnetic fields are determined by obtaining the distribution of the magnetic field perpendicular to the tape face and the current density integrated over the tape thickness. Nonlinear integral equations for the perpendicular field are numerically solved at each step during a cycle of external field, and the magnetization losses are finally estimated from the product of local electric field and current density. The influences of the field dependence of critical current density on the losses are discussed quantitatively. [Copyright &y& Elsevier]

Abstract: Thin, flexible and tough bucky paper fabricated by filtering a stable suspension of double-walled carbon nanotubes (DWNTs) was characterized from the viewpoint of its pore structure and oxidation stability as compared with that derived from single-walled carbon nanotubes (SWNTs). The N2 adsorption isotherms of DWNTs and SWNTs at 77K were of type II and type IV, respectively, and also the micropore volume in DWNTs was three times greater than that in SWNTs. The onset temperature of oxidation in DWNTs was enhanced by ca. 200°C due to their coaxial structure. The expected high mechanical and electrical properties when combined with their high surface area and high structural integrity make the DWNTs bucky paper promising materials for numerous applications. [Copyright &y& Elsevier]

Abstract: Here we describe synthesis of very unusual multi-walled carbon nanotubes through a catalytic chemical vapor deposition method using a floating reactant method and subsequent thermal treatment up to 2600°C in a large quantity. Main characteristics of these nanotubes are (1) relatively wide distribution of diameters ranging from 20 to 70nm and linear, long macro-morphology (aspect ratio >100), (2) highly straight and crystalline layers, (3) high purity through removal of metallic impurity, (4) very low interlayer spacing (0.3385nm) and low R value (I D/I G =0.0717), (5) high G′ intensity over intensity of G band (G′/G=0.85) and strongly negative magnetoresistance value of −1.08% at 77K and 1T. The unusual microstructure of thin multi-walled carbon nanotubes with a partially facetted cross-sectional shape caused by thermal treatment is mainly ascribed to abrupt density changes (from 1.89 to 2.1g/cm3) within a confined nanosized space, accompanying with the phase separation. [Copyright &y& Elsevier]

Abstract: We have studied the dynamics of photocarriers in anatase phase of TiO2 with time-resolved spectroscopy of self-trapped exciton (STE) luminescence. It is found that the decay curve of luminescence under one-photon excitation well above the band gap energy shows power-law behavior, suggesting that spatial separation of an electron–hole pair occurs under interband excitation. A similar result is obtained under two-photon excitation. We conclude that the carrier separation is ascribed to intrinsic dynamical properties of photocarriers in anatase. It is inferred that the carrier separation occurs during energy relaxation towards the band bottom. Temperature dependence of the decay curve is also discussed in terms of thermal dissociation of STEs. [Copyright &y& Elsevier]

In order to reproduce the experimental results of AC losses in a Bi-2223 Ag-sheathed tape exposed to the external magnetic field with an arbitrary angle to the broadest face, we calculate the AC losses by means of the two-dimensional finite element method that directly analyzes the magnetic field distribution around the wire. It is assumed that the voltage–current characteristics are represented by the power-law model including the dependence of both the critical current density and n-value on an effective perpendicular component of applied magnetic field. The obtained numerical results have a good agreement with the experimental results in the large amplitude of applied magnetic field. [Copyright &y& Elsevier]

AC losses are numerically evaluated in superconductors with a rectangular cross section and an infinite length for the application of either transport current or external magnetic field perpendicular to the broadest face. It is assumed that the electromagnetic response is determined by Bean''s critical state model, in which the critical current density is independent of the magnitude of local magnetic field. In this case, the AC loss per cycle can be estimated directly from the magnetic-flux distribution inside the superconducting wire at the peak of cyclic field. By investigating the influence of the aspect ratio of wire cross section on the losses, it is concluded that conventional expressions for a strip are almost applicable to a very thin but finite wire. [Copyright &y& Elsevier]

It is important to measure retentions and depth profiles of deuterium and tritium on plasma facing materials to understand plasma-wall interactions. The nuclear reaction analysis (NRA) has been established using a deuteron beam with an adjustable energy. By means of the NRA, depth profiles of deuterium and tritium on the surface of JT-60 divertor graphite tiles irradiated with DD burning were obtained. The NRA method showed that the average concentrations of the deuterium retained in the surface of two different were 1.3 × 1016 and 0.3 × 1016 cm-2. α-particles from the T(d, α)n reaction were measured from a dome unit tile of JT-60U W-shaped divertor and the measured activity of tritium was about 18 kBq/cm2. The peak energy of the α spectrum obtained with the NRA was about 1.2 MeV. This result implies that energetic tritons were implanted in the divertor graphite tile. [Copyright &y& Elsevier]

The T2 phase in the Mo–Si–B system has great potential for ultra-high temperature structural applications. We examined creep of the single crystalline and polycrystalline T2 phase. The steady-state creep rate of the [021] oriented specimens is as low as 3.1×10-8 s-1 at 1500 °C and 432 MPa. The minimum creep rates at 1500 °C of the [001] oriented and polycrystalline specimens are 6.9×10-8 s-1 at 600 MPa and 3.0×10-8 s-1 at 300 MPa, respectively. The activation energy for creep was found to be ∼740 and ∼400 kJ mol-1 for [021] and [001] oriented specimens, respectively. Stress exponent for creep was found to be 6.8, 4.3 and 4.6 for [021] and [001] oriented and polycrystalline specimens, respectively. Creep resistance of the single crystalline and polycrystalline T2 specimens is much better than that of MoSi2 and Si3N4 base structural ceramics. [Copyright &y& Elsevier]

High purity single crystals of Mo5SiB2(D8l), Mo5Si3(D8m), Mo5Si3C(D88) and Ti5Si3(D88) and polycrystals of Nb5SiB2(D8l) and V5SiB2(D8l) have been grown and their electrical and thermal properties have been measured. The resistivity of all transition metal 5-3 silicides exhibit a negative curvature with a tendency towards saturation when it is plotted as a function of temperature. The resistivity of Mo5SiB2, Mo5Si3 and Mo5Si3C is saturated at a lower value than that of Ti5Si3, Nb5SiB2 and V5SiB2. In Mo5Si3C where room temperature resistivity is large because of large residual resistivity, resistivity saturation is pronounced and results in almost temperature independent resistivity. Thermal conductivities for Mo5SiB2, Mo5Si3, Mo5Si3C and Ti5Si3 are about 27, 19, 8.5 and 11 W/mK, respectively. Mo5Si3C exhibits almost temperature independent thermoelectric power along [112¯0]. On the other hand, thermoelectric power of Mo5Si3C along [0001] and Mo5SiB2 decreases monotonically with increasing temperature. [Copyright &y& Elsevier]

Leaf explants of Caladium ‘Pink Cloud’ were cultured in vitro on MS medium containing various auxins (NAA, IBA, IAA, 2,4,5-T and 2,4-D) in combination with cytokinin (BA). NAA gave the most vigorous in vitro propagation of this plant, and only 15% of the plants were leaf-colour variants on the medium containing 0.5 μmol NAA. Leaf colour variation was observed in all plants regenerated on the medium containing 2,4-D at 0.5–4.5 μmol. In hormone-free medium, only a few leaf-colour variants (6%) occurred, but the rate of plant regeneration was very low. Application of 0.5 μmol NAA together with 4.5 μmol BA seemed to be the most appropriate for in vitro propagation of Caladium ‘Pink Cloud’ with only a few leaf-colour variants. [Copyright &y& Elsevier]

Highly disordered carbon nanotube is obtained through a catalytic thermal chemical vapor deposition method, especially, using the floating reactant method. The results of annealing highly disordered carbon nanotube are (1) removal of metallic compounds, (2) structural conversion into multi-wall carbon nanotube with a little faceted cross-section, and (3) development of a tug morphology in carbon nanotubes. The characteristic observed in annealed multi-wall carbon nanotubes make them useful as a filler in advanced composite. [Copyright &y& Elsevier]

The influence of effective vacuum part is numerically evaluated on AC losses in superconducting wires calculated by means of a two-dimensional finite element method, which is formulated with a self-magnetic field due to an induced current as unknown. In the present method, the high-resistivity metal around the wires is needed for the sake of the simplicity in program coding. The superconducting wires carry an alternating transport current or are exposed to an external AC magnetic field. The AC losses are numerically calculated for square and circular effective vacuum parts with wide ranges of the sizes and the resistivity. Relative errors in the obtained results are discussed as compared with conventional analytical predictions. [Copyright &y& Elsevier]

High purity single crystals of the Mo5Si3C phase with the D88 type structure have been grown and their physical and mechanical properties have been measured. The composition of single crystals is Mo4.66Si3.00C0.402. Lattice constants of the compound are a=0.7286 nm and c=0.5046 nm. Vickers micro-hardness and fracture toughness are 13.4 MPa and 1.3 MPa m1/2, respectively. The anisotropy ratio of thermal expansion coefficient (αc/αa) of the compound is approximately 2 at 773 K. In contrast, the elastic properties for the compound are nearly isotropic. The deformation behavior of the compound has been studied in compression using [0001], [1340], [2249] oriented single crystals. These single crystals can be deformed plastically at temperatures higher than 1573 K. Slip occurs on {0001}<11¯20> and an unidentified non-basal system. [Copyright &y& Elsevier]

A 36-V valve-regulated lead-acid (VRLA) battery used in a 42-V power system has been developed for the Toyota Hybrid System-Mild (THS-M) vehicle to meet the large electrical power requirements of hybrid electric vehicles (HEVs) and the increasing power demands on modern automobile electrical systems. The battery has a longer cycle-life in HEV use through the application of ultra high-density active-material and an anti-corrosive grid alloy for the positive plates, special additives for the negative plates, and absorbent glass mat with less contraction for the separators. [Copyright &y& Elsevier]

Cone-stacked nanotubes with thick layers of deposited carbon obtained by a catalytic chemical vapor deposition method are annealed at high temperature. Phase separation between cone-stacked nanotubes and amorphous carbon layers occurs during annealing due to different structural transformation behaviors, resulting in the formation of multi-wall carbon nanotubes containing a cone-type multi-shell arrangement. The apex angles of the nanocones are about 40°. This type of carbon nanotube shows different physical and electrical properties. [Copyright &y& Elsevier]

Explants from various parts of Caladium bicolor Ait. plants were cultured on MS medium containing 1 ppm naphthalene acetic acid (NAA) and 1 ppm 6-benzyladenine (BA). Variations in the shape and color pattern were observed in the regenerated plants. In plants regenerated from shoot tip explants including the two youngest leaves, young leaves (third and fourth leaves from the top), unexpanded leaves (fifth or sixth leaves), expanded leaves and petiole, the frequency of the occurrence of variants was 14, 24, 41, 53 and 70%, respectively. Plants regenerated from young leaves of lateral buds or root tips also produced only a few variants (12–14%). Thus, explants from younger tissue having meristematic tissue produced fewer variations than explants from older tissue. The mode of variation (color pattern and shape of leaves) also varied with the age of the explant. We conclude that young tissue should be used to propagate Caladium plants by tissue culture. [Copyright &y& Elsevier]

We have studied methylthiolate (MeS), ethylthiolate (EtS), and butylthiolate (BuS) adsorption on the Au(1 1 1) surface using density functional theory within a generalized gradient approximation (GGA). EtS and BuS are also adsorbed at the bridge site slightly off-centered towards the fcc-hollow site and the S–C bond is tilted from the surface normal by 52°. The S 2p core level shift of MeS adsorbed at the bridge site agrees quite well with the experimental results, further supporting the bridge configuration. Finally, we have examined several possible MeS configurations in the c(4√ of 3×23×2√ of 3) superstructure. At present, however, we cannot obtain consistent results with the experimental ones, presumably due to the limited accuracy of the present GGA functional and/or substrate reconstructions. [Copyright &y& Elsevier]

Magnetization and magnetoresistance of A-type antiferromagnet Pr0.45Sr0.55MnO3 have been measured by means of pulsed magnetic fields up to 45 T. Below TN∼215 K, metamagnetic transitions and attendant discontinuous decreases in resistivity were observed. Above the transition fields, the transport anisotropy is reduced compared with that in the antiferromagnetic state. The observed ferromagnetic transition and resistivity change indicate the simultaneous collapse of spin and orbital order by magnetic field. [Copyright &y& Elsevier]

The effect of grinding on cup-stacked carbon nanotubes is studied. The application of a bending force on the sidewall of such carbon nanotubes, that is higher than the Van der Waals force acting between the cups, results in the shortening of carbon nanotubes and the formation of nano-barrels exhibiting an increased number of accessible active sites (represented by the ends of graphitic planes) and anisotropic properties at both ends. [Copyright &y& Elsevier]

Low-temperature annealing after molecular-beam epitaxial growth of III–V-based diluted magnetic semiconductors, (Ga,Mn)As and (In,Mn)As have been found to improve the crystallinity of the films. That is, the Curie temperature and the conductivity are greatly enhanced. This effect is probably due to the removal of excess As atoms which passivate doped Mn acceptors. The present method provides a way for carrying out reproducible systematic studies of these materials. [Copyright &y& Elsevier]

Abstract: Neutron transport calculations have been carried out to assess the capability of zirconium borohydride (Zr(BH4)4) and zirconium hydride (ZrH2) as advanced shield materials, because excellent shields can be used to protect outer structural materials from serious activation. The neutron shielding capability of Zr(BH4)4 is lower than ZrH2, even though the hydrogen density of Zr(BH4)4 is slightly higher than that of ZrH2. High-Z atoms are effective in neutron shielding as well as hydrogen atoms. The combination of steel and Zr(BH4)4 can improve the neutron shielding capability. The combinations of (Zr(BH4)4 +F82H) and (ZrH2 +F82H) can reduce the thickness of the shield by 6.5% and 19% compared to (water+F82H), respectively. The neutron flux for Zr(BH4)4 is drastically reduced in the range of neutron energy below 100eV compared to other materials, due to the effect of boron, which can lead to a reduction of radwaste from fusion reactors. [Copyright &y& Elsevier]