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Superconducting magnetic bearings (SMBs) are usually composed of superconducting (SC) bulk and permanent magnet (PM). These SMBs are based on pinning forces between SC bulk and PM. In this paper, new type SMBs composed of SC bulk, SC coil and PM are proposed. In order to compare SMB Type-I with Type-II, impulse responses in the horizontal direction are performed. Then, natural damped vibration curves for impulse responses are observed. The damping coefficient for the SMB Type-II is very larger than the Type-I. The damping coefficient depends on the position of SC coil.

The standardized acrylonitrile-butadiene-styrene (ABS) or polycarbonate (PC) resin disk with added flame retardants (FRs) has a potential to be a suitable tool for predictions of both aging of the plastic materials and release rate of a flame retardants exposed under different outdoor and indoor conditions. The experiments examined the dynamics and kinetics of the release of dechlorane plus, tetrabromobisphenol A, triphenyl phosphate and antimony trioxide as FRs from a standardized plastic disk before and after exposure to artificial sunlight. Assessments were carried out independently to measure changes in the content of flame retardants and monitor the flame retardancy and flexural properties after exposure (60 W/m2) over a period of 200 h and 500 h, which are reasonable to predict a short-time tendency and to receive any advice for a safe re-use. The releases of three organic flame retardants and four elements (Cl, Br, P and Sb) from weathered ABS and PC disks were very limited, except for surface delamination and resin microparticles. Triphenyl phosphate was stable without hydrolysis, while the degradation of tetrabromobisphenol A was observed (approximately 20% decrease for ABS disk and approximately 50% decrease for PC disk). During the study, no significant differences in the flame retardancy and flexural properties of the disks could be detected. In practice, the results obtained from disks of acrylonitrile-butadiene-styrene or polycarbonate resin with selected flame retardants used in specific conditions may provide technical expertise regarding weathering processes.

We describe in detail seabed features on a deep-sea terrace of the Japan Trench caused by the 2011 Tohoku Earthquake based on visual seafloor observations. Data of this study was acquired using towed camera surveys and a remotely operated vehicle (ROV) dive in water depths between about 1300 and 2300 m and was conducted three, six and twelve months after the 2011. Damaged benthic organisms and disseminated bio-fragments might record the flow directions of the seismically or tsunami induced turbidity current. These records would be preserved into the geological record, if they remain undisturbed and getting buried before being reworked.

Zinc complexes of 3-hydroxymethyl-131-oxo-chlorins possessing a vinyl or its trans-substituted group at the 20-position were prepared through regioselective bromination and successive palladium-catalyzed cross-coupling reactions from naturally occurring chlorophyll-a. The synthetic zinc chlorophyll-a derivatives self-aggregated in an aqueous Triton X-100 micelle solution to give red-shifted and broadened electronic absorption bands, which were similar to those of bacteriochlorophyll-c/d self-aggregates in the main light-harvesting antenna systems of green photosynthetic bacteria. Because of the sterically demanded perpendicular orientation of the (un)substituted ethenyl group to the chlorin π-system, the present model compounds had less J-aggregation ability in a slipped π–π interaction fashion than the corresponding saturated ethyl-type analogs, while halogenations at the terminal of the 20-vinyl group enhanced the ability due to their electron-withdrawing effect.

Zinc methyl 20-substituted 3 1 -demethyl-bacteriopheophorbides- d were prepared through palladium-catalyzed cross-coupling of chlorophyll- a derivatives. The synthetic zinc 3 1 -hydroxy-13 1 -oxo-chlorins possessing a(n) (un)substituted ethynyl or butadiynyl group at the 20-position were good models for bacteriochlorophylls- c / d found solely in chlorosomes, the main light-harvesting antennas of green photosynthetic bacteria. Similarly as in natural chlorosomes, the synthetic models self-aggregated in an aqueous Triton X-100 solution to form large oligomers with red-shifted and broadened electronic absorption bands. While a phenyl group directly connected with the chlorin π-system at the 20-position disturbed the chlorosomal self-aggregation, the insertion of an ethynylene group between the two functional groups reduced the steric hindrance around the 20-position and was useful for the facile formation of the self-aggregates. A similar substitution effect was observed in the 20-ethynyl to butadiynyl moieties bearing a sterically bulky trimethylsilyl group at the terminal position.

The Kamioka mine, located in Gifu Prefecture in Japan, is famous for the large water Cherenkov detector system, the Super-Kamiokande. The Kamioka skarn-type Pb–Zn deposits are formed in crystalline limestone and are replaced by skarn minerals within the Hida metamorphic rocks. The Kamioka deposits mainly consist of the Tochibora, Maruyama, and Mozumi deposits. The present study focuses on the ore-forming hydrothermal fluid activity in the Kamioka deposits and the peripheral exploration area based on the carbon and oxygen isotope ratios of calcite and rare earth element (REE) analyses. The carbon and oxygen isotope ratios of crystalline limestone (as the host rock) are not homogeneous, and depending on the degree of hydrothermal activity, they decreased to various degrees because of the reaction with the ore fluids. Thus, the carbon and oxygen isotope ratios of crystalline limestone can be used as an indicator of the influence of the hydrothermal fluids for the ore mineralization. The REE contents in the ores of igneous origin are one order of magnitude higher than the limestone origin. Further, depending on the formation temperatures, calcites precipitated during ore mineralization have a stable carbon isotope ratio and a widely varying oxygen isotope ratios. The Kamioka district fracture system is likely a major control factor on ore mineralization from hydrothermal activity. In addition, the skarnization-related ore-forming fluids are mostly meteoric in origin, confirming the conclusions from previous studies.

The determination of chlorine (Cl) in plastic using isotope dilution inductively coupled plasma mass spectrometry (ID-ICPMS) combined with different sample pretreatment procedures was examined in the present study. In order to validate the analytical results for Cl, certified reference materials (CRMs) of BCR 680 and BCR 681, which have certified Cl concentrations in the polyethylene resin pellets, were used. Both the microwave acid digestion and combustion-absorbent procedures were examined as different sample pretreatment procedures, and ICP triple quad mass spectrometer (ICP-MS/MS) with a mass-shift method in MS/MS mode using collision reaction gas of hydrogen (H2) was applied for the accurate and precise determination of Cl by ID-ICPMS. In the case of the microwave acid digestion procedure combined with ID-ICPMS, an accurate determination could not be demonstrated due to a large Cl signal from the reagent blank, which resulted in a poor signal to background (S/B) ratio as well as poor isotope ratio measurement of Cl in ID-ICPMS. On the other hand, an accurate determination could be demonstrated using the combustion-absorbent procedure since any large Cl signal from the absorbent (0.1% H2O2) used as the reagent blank were not observed, which could provide a sufficient S/B ratio of Cl to achieve an accurate and precise Cl isotope ratio measurement in ID-ICPMS. From these results, though the microwave acid digestion procedure was unfortunately considered to be ineffective, the combustion-absorbent procedure combined with ID-ICPMS using ICP-MS/MS could be used for the accurate and precise determination of Cl in plastics.

The analytical method of ultra-trace sulfur (S) in high-purity metal by isotope dilution inductively coupled plasma mass spectrometry (ID-ICP-MS) combined with chemical separation procedure was developed in the present study. In order to determine the ultra-trace S in high-purity metal, a chemical separation with alumina column was carried out before ICP-MS measurement. This method enabled to prevent the polyatomic ion interference arising from the metal matrix and the signal suppression derived from the space charge effect in ICP-MS. In order to achieve high sensitive analysis, an ICP-sector field mass spectrometer (ICP-SFMS) was used. The isolation of polyatomic ion interference with respect to S was also carried out in medium-resolution mode. In addition, measurement conditions including detector dead time, which affects the precision and accuracy of the isotope dilution method, and washout conditions that were employed to reduce memory effects were optimized. The developed method was validated by the determination of S in a high-purity iron reference material (JSS-001–4). The analytical result obtained by the developed method (1.86 mg kg−1 ± 0.12 mg kg−1 (k = 2)) was in good agreement with the certified value (1.90 mg kg−1 ± 0.42 mg kg−1). The method was also applied to the determination of S in high-purity zinc, revealing a content of 0.08 mg kg−1 ± 0.08 mg kg−1 (k = 2). Since the developed method enabled the determination of ultra-trace S at μg kg−1 level in the high-purity zinc, it is expected to be useful for high sensitive and accurate determination of ultra-trace S in high-purity metals.

The analytical method for ultra-trace metal impurities at μg kg-1 level in high-purity Cd was examined by inductively coupled plasma mass spectrometry (ICP-MS) combined with matrix separation by Bio-Rad AG MP-1M anion exchange resin. After the separation of Cd, the metal impurities such as Li, In, Cr, Mn, Fe, Co, Ni, Cu, Ga, Sr, Ba and Pb were measured by an ICP-quadrupole mass spectrometer (ICP-QMS) and ICP-sector field mass spectrometer (ICP-SFMS). From the comparison of measured results, it was evaluated that the analytical sensitivity by ICP-SFMS was 10 times higher than ICP-QMS. In addition, ICP-SFMS could obtain determined values of Li and Fe that could not be determined by ICP-QMS. These results suggest the ICP-SFMS combined with matrix separation by anion exchange resin could be utilized for the determination of ultra-trace metal impurities in high-purity materials for the assessment of the purity of the materials.

Zinc 3-hydroxymethyl-131-oxo-chlorins bearing a variety of primary alkyl groups at the 20-position were prepared as models of bacteriochlorophyll-c by chemical modification of naturally occurring chlorophyll-a. The synthetic chlorophyll-a derivatives self-aggregated in an aqueous Triton X-100 solution to afford large oligomers whose Soret and Qy bands were red-shifted and broadened, compared with the bands of their monomers in tetrahydrofuran. The oligomeric bands are similar to those of bacteriochlorophyll-c self-aggregates in chlorosomes, the main light-harvesting antennae of photosynthetic green bacteria. The 20-alkylation led to bathochromic shifts of the visible Soret maxima in J-type self-aggregates of the synthetic models, while elongation of the 20-alkyl group decreased the chlorosomal Qy maxima due to an increase in steric hindrance. Considering the light-harvesting and energy-transferring processes in a chlorosome, the 20-methylation in bacteriochlorophyll-c would be more suitable for efficient culturing of green bacteria than the 20-ethylation and propylation as well as the 20-unsubstitution in bacteriochlorophyll-d.

In this paper, the immediate estimation system for wide-area distribution of seismic intensity by using seismic intensity information network system is discussed. In general, although seismic intensity on each seismic intensity monitoring points can be obtained by using seismic intensity information network system within a few minutes after earthquake occurs, wide area distribution of seismic intensity is not obtained. This is because the number of seismic intensity monitoring points on the network system are very few and limited to estimate distribution of seismic intensity. However, by using other information, such as soil profiles on the ground of local areas and attenuation characteristics of seismic intensity, distribution of seismic intensity can be estimated with computer simulation considering seismic wave amplification on the ground immediately after seismic intensity information form the network system is obtained. Especially, array density and optimum arrangement of seismic intensity monitoring...

Flame retardants (FRs) are useful because they can prevent combustion and delay the spread of fire after the ignition on commercial products containing plastics. However, such commercial products could be a primary source of environmental contamination with FRs. Plastic disks containing FRs were prepared to elucidate changes in the concentrations of the FRs after weathering tests. Acrylonitrile-butadiene-styrene (ABS) and polycarbonate (PC) resin were separately kneaded with a combination of three organic FRs [Dechlorane plus (DP), tetrabromobisphenol A (TBBPA), and triphenyl phosphate (TPhP)] and one inorganic FR [antimony trioxide (Sb2O3)]. The concentrations of TBBPA/TPhP and DP/Sb2O3 in the final preparations were respectively 1000 and 500 mg/kg in compliance with the RoHS directive on organobromine FR. The concentrations of elements in the final preparations were 300 mg/kg for chlorine, 600 mg/kg for bromine, 100 mg/kg for phosphorus, and 400 mg/kg for antimony, respectively. The analytical concentrations (three FRs and four elements) were consistent with the expected concentrations (maximum difference −9.5% in the PC disks). The FRs and elements in the disks were sufficiently homogenous (maximum inhomogeneity 4.3% in the PC disks). The prepared disks were subjected to weathering tests; the concentrations of TBBPA in the disks decreased significantly (30 to 40%) whereas the concentrations of the elements did not change under the condition of this study. On the other hand, there were no drastic differences on relationships of FRs and elements such as DP/chlorine and TPhP/phosphorus.