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71.
Yamamoto A Kakutani N Yamamoto K Kamiura T Miyakoda H 《Environmental science & technology》2006,40(13):4132-4137
A highly sensitive and uncomplicated method of analyzing steroidal hormones in river and estuarine water samples was developed using a liquid chromatography tandem mass spectrometer equipped with an electrospray ionization (ESI) source and atmospheric pressure photoionization (APPI) source. Steroidal hormones included not only estrogen but also androgen and conjugates of these two. APPI displayed greater sensitivity than ESI for most of the unconjugated steroids examined, with very high sensitivity for testosterone and 4-androstene-3,17-dione in particular. For conjugated hormones, in contrast, ESI was more effective. The method developed was applied to the determination of hormones in the rivers of Osaka City and their estuaries, where the hormones detected were affected by the effluent from municipal wastewater treatment plants (WWTPs), and hormone concentration values were comparable to those reported in previous studies of such effluent. Because of the two-way flow and stagnancy of streams and watercourses, continuous input of steroidal hormones from WWTPs seems to bring about local accumulation. Levels of androgen were 1 order of magnitude lower than those of estrogen. Estrone, estrone 3-sulfate, and 4-androstene-3,17-dione were detected in almost all water samples, with maxima of 51, 5.1, and 6.4 ng L(-1), respectively. 相似文献
72.
Mitamura K Imae T Mouri E Torikai N Matsuoka H Nakamura T 《Journal of nanoscience and nanotechnology》2006,6(1):36-42
Hybrid Langmuir and Langmuir-Blodgett monolayers of a perfluorooctadecanoic acid mixed with a rigid block copolymer, poly(3,5-bis(3,5-bis(benzyloxy)benzyloxy)benzyl methacrylate-randommethacrylic acid)-block-poly(2-perfluorooctylethyl acrylate), which is composed of benzyloxy dendron side chains and perfluorinated side chains, were prepared and characterized by surface pressure-surface area isotherms, atomic force microscopic images and neutron and X-ray reflectometries. The two-dimensionally phase-separated structures of monolayer films and their morphologies with plateau and terrace were confirmed. The monolayers were separated into a dendron layer, a perfluorinated layer, and a carboxyl layer. The layer formation is originated not only in the intermolecular interaction between a perfluorooctadecanoic acid and a block copolymer but also in the geometry of the molecules. Especially, the amphiphilicity of perfluorinated surfactant plays a role to the ordered array of the block copolymers. 相似文献
73.
We examined muscle spindles in the posterior cricoarytenoid (PCA) muscle of the marmoset. The spindle capsule contained only one intrafusal muscle fiber which did not form a typical aggregation of equatorial nuclei such as bags and chains. The intrafusal fiber was innervated by sensory endings which branched and arranged irregularly. These sensory endings lay on the surface of the fiber in shallow grooves or deeply penetrated into it. These findings suggest that the muscle spindles in the marmoset PCA muscle are strikingly different in the structure of intrafusal fibers in the arrangement of sensory endings from those in common mammalian skeletal muscles. 相似文献
74.
Finite-difference time-domain (FDTD) analysis has been used to predict the time-resolved reflectance from multilayered slabs with a nonscattering layer. Light propagation across the nonscattering layer was calculated based on the light intensity characteristics along a ray in free space. Additional equivalent source functions due to light from scattering regions across the nonscattering region were introduced into the diffusion equation and an additional set of the diffusion equation was solved by FDTD analysis by employing new boundary conditions. The formulation was used to calculate time-resolved reflectances of three- and four-layered slabs containing a nonscattering layer. The received light intensity and the mean time of flight estimated from the time-resolved reflectance are in reasonable agreement with previously reported experimental data and Monte Carlo simulations. 相似文献
75.
Naoya Masahashi Yoshiteru Mizukoshi Satoshi Semboshi Kazuyo Ohmura Shuji Hanada 《Thin solid films》2012,520(15):4956-4964
Photocatalytic activity and wettability of the anodic oxide layer on Ti6Al4V prepared by anodization in a sulfuric acid electrolyte are explored. The oxide is composed mainly of TiO2 with V2O5, VO2 and Al2O3. The crystal structure of the TiO2 varies from anatase to rutile with the sulfuric acid concentration in the electrolyte. Anatase exhibits better photocatalytic activity compared with rutile, which is different from those on Ti and Ti-Nb-Sn alloy. Contact angles of the oxides decrease with ultraviolet light illumination, and hydrophilicity is observed in the rutile oxide. Both photocatalytic activity and hydrophilicity are inferior to the corresponding Ti and Ti-Nb-Sn alloy, which is explained by the presence of Al2O3 in the anodic oxide. 相似文献
76.
Ando T Matsumoto N Ohtake Y Takiguchi Y Inoue T 《Journal of the Optical Society of America. A, Optics, image science, and vision》2010,27(12):2602-2612
We investigate optical singularities in coaxial superpositions of two Laguerre-Gaussian (LG) modes with a common beam waist from the viewpoints of a general formulation of phase structure, experimental generation of various superposition beams, and evaluation of the generated beams' fidelity. By applying a holographic phase-amplitude modulation scheme using a phase-modulation-type spatial light modulator, output fidelity beyond 0.960 was observed under several typical conditions. Additionally, an elliptic-type folded singularity, which provides a different class of phase structures from familiar helical singularities, was predicted and observed in a superposition involving two LG modes of both radially and azimuthally higher orders. 相似文献
77.
Makoto Hirayama Hiroki Shinozaki Naoya Kasai Tsutomu Otaki 《International Journal of Hydrogen Energy》2018,43(27):12584-12594
This paper describes an investigation into the acceptability of installing hydrogen dispensers in public areas based on risk assessments. Because gasoline dispenser risks have been widely accepted for many years, they were used as a benchmark in this study to analyze the risks of hydrogen dispensers. More specifically, we performed risk assessments for both hydrogen and gasoline dispensers and then compared and analyzed the results. We began the process by creating models for both hydrogen and gasoline dispensers that represented their various specifications and elements. Next, potential accident scenarios for each dispenser model were identified by failure mode effect analysis (FMEA) and hazard and operability study (HAZOP). The risks of each scenario were then qualitatively evaluated and the results were organized into risk matrices. By comparing the results of both hydrogen and gasoline dispensers with and without existing safety measures, the appropriateness of their safety measures were validated. Furthermore, by comparing the results of hydrogen and gasoline dispenser safety measures, it was confirmed that the risk levels of the two types were practically equivalent. Therefore, we concluded that the risks involved with installing hydrogen dispensers in public areas can be considered acceptable. 相似文献
78.
It is necessary in factories to assess the severity of the surface defects of castings, as a slight surface defect will be taken as qualified when it brings no bad effect or it can be removed by the subsequent processing. In practical production, professional technicians visually inspect the surface defect severity according to their individual experience. Therefore, it is difficult for them to maintain the same standard and accuracy in the subjective, tedious and labor-intensive work. Recently, image processing techniques based on optical images have been applied to achieve better accuracy and high efficiency. Unfortunately, optical images cannot directly quantify surface depth, which works as a crucial factor in the practical assessment of surface defect severity. The surface roughness evaluation algorithm, which takes into account of both area and depth information of the assessed surface, was applied to directly characterize surface defect severity based on surface asperity rather than optical image. The results using standard casting pieces show that surface defect severity has no apparent dependence on surface roughness. However, the subsequent results show that the root-mean-squared-deviation (RMSD) of surface gradient of flow line defects positively correlates with the increase of defect severity. The other types of defect do not present such tendency. Thus, practical workpieces with flow line defects on the surface were used to verify the universality of this tendency. The results show that surface roughness of an unqualified workpiece is larger than that of a qualified workpiece after surface slope adjustment, but presents no obvious coincidence before the adjustment. In contrast, the RMSD of an unqualified workpiece, no matter before or after the adjustment, is larger than that of a qualified one. 相似文献
79.
The objective of this study is to experimentally examine the characteristics of transient vortices in the boundary layer on a disk undergoing both rotation and orbital motion. The velocity fluctuations on a rotating, orbiting disk (disk radius equal to orbital radius) are measured by the hot-wire method, and the effects of orbital motion on the transient vortices in the boundary layer are examined. When the ratio of the orbital speed to the speed of rotation is i-0.025, the interval of transient vortices depends on only the orbital radius, regardless of the directions of rota- tion and orbital motion. The rate of low-frequency disturbances increases as the orbital speed increases, and the vortices induced by these low-frequency disturbances travel over the disk and then develop in the region of in- creased velocity. Consequently, no vortices generated on a rotating disk under orbital motion are stationary rela- tive to the disk. 相似文献
80.
Naoya Katayama 《时间序列分析杂志》2008,29(2):359-370
Abstract. The portmanteau statistic is based on the first m‐residual autocorrelations, and is used for diagnostic checks on the adequacy of fit of a model. In this article, we propose a modified portmanteau statistic with a correction term that allows for the use of small values of m for the chi‐squared test. For this modification, we take a different approach to that suggested by Ljung [Biometrika (1986), Vol. 73, pp. 725–30]. Their empirical behaviour is clarified using asymptotic theory. 相似文献