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101.
Noritaka Tsunemasa Hideo Yamazaki 《International journal of molecular sciences》2014,15(6):9991-10004
Accumulation of Ot alternative antifoulants in sediment is the focus of this research. Much research had been done on surface sediment, but in this report, the accumulation in the sediment core was studied. The Ot alternative antifoulants, Diuron, Sea-Nine211, and Irgarol 1051, and the latter’s degradation product, M1, were investigated in five samples from the northern part of Hiroshima Bay. Ot compounds (tributyltin (TBT) and triphenyltin (TPT)) were also investigated for comparison. In addition, metal (Pb, Cu, Zn, Fe and Mn) levels and chronology were measured to better understand what happens after accumulation on the sea floor. It was discovered that Ot alternative antifoulant accumulation characteristics in sediment were like Ot compounds, with the concentration in the sediment core being much higher than surface sediment. The concentration in sediment seems to have been affected by the regulation of Ot compounds in 1990, due to the concentration of Ot alternative antifoulants and Ot compounds at the survey point in front of the dock, showing an increase from almost the same layer after the regulation. 相似文献
102.
Hideo Tajima Yuta Yoshida Satoko Abiko Kazuaki Yamagiwa 《Chemical engineering journal (Lausanne, Switzerland : 1996)》2010,156(2):479-486
Temperature-sensitive hydrogel beads were prepared by Kenics static mixer technology. The temperature-sensitive monomer N,N-diethylacrylamide and photo-crosslinkable pre-polymer ENT were used as model hydrogel materials. Drop dispersion of high viscosity polymer material in low viscosity hexadecane was made using the static mixer. Drops of a solution of the mixed materials were rapidly photo-crosslinked by UV irradiation after mixing in the static mixer, and spherical hydrogel beads with narrow, normal size distribution were thus prepared. The Kenics static mixer is a useful device for the preparation of spherical beads of temperature-sensitive hydrogels. The Sauter Mean Diameter of the hydrogel beads swollen in deionized water at 293 K was measured. The experimentally determined dimensionless swollen hydrogel bead diameter was well correlated with the Weber number, degree of swelling and viscosity ratio. The effects of gelation and ENT addition on the bead size were evaluated from the degree of swelling. The correlation equation can be used for size adjustment of temperature-sensitive spherical hydrogel beads. 相似文献
103.
Toshifumi Ohkubo Kenji Tanaka Terunao Hirota Hiroshi Hosaka Kiyoshi Itao Yoko Shinohara Hideo Maeda Kenji Kato Yasuyuki Mitsuoka Kunio Nakajima 《Microsystem Technologies》2005,11(8-10):1094-1101
Advances in the digital network society require both higher density and higher transfer rates in all sorts of storage systems. Especially in optical recording, the trend toward higher density and larger capacity requires novel surface-recording technologies that can drastically diminish head-to-medium spacing, resulting in an improvement in spatial resolution and, finally, a higher recording density. To this end, we have already proposed a novel contact optical head slider that is able to almost cancel the suspension load by generating hydrodynamic pressure, thus realizing a lower net contact force. Evaluating the dynamic contact force is requisite in realizing its stable sliding operation and higher signal readout performance. In this study, a continuous acoustic emission (AE) signal was utilized to detect the dynamic contact force. AE signal modulation was compared with the applied out-of-plane acceleration on a medium generated by a spindle combined piezo-electric actuator. It was clarified that the detected AE modulation amplitude was approximately proportional to the applied acceleration, and that utilizing AE modulation will be a useful method for evaluating dynamic contact force. 相似文献
104.
Shin-ichi Morita Yasutaka Hayamizu Akihiko Horibe Naoto Haruki Hideo Inaba 《热科学学报(英文版)》2013,22(2):145-151
Recently, much attention has been paid to investigate the latent heat storage system. Using of ice heat storage system brings an equalization of electric power demand, because it will solved the electric -power-demand-concentration on day-time of summer by the air conditioning. The flowable latent heat storage material, Oil/Water type emulsion, microencapsulated latent heat material-water mixture or ice slurry, etc., is enable to transport the latent heat in a pipe. The flowable latent heat storage material can realize the pipe size reduction and system efficiency improvement. Supercooling phenomenon of the dispersed latent heat storage material in continuous phase brings the obstruction of latent heat storage. The latent heat storage rates of dispersed water drops in W/O (Water/Oil) emulsion are investigated experimentally in this study. The water drops in emulsion has the diameter within 3 ~ 25μm, the averaged water drop diameter is 7.3μm and the standard deviation is 2.9μm. The direct contact heat exchange method is chosen as the phase change rate evaluation of water drops in W/O emulsion. The supercooled temperature and the cooling rate are set as parameters of this study. The evaluation is performed by comparison between the results of this study and the past research. The obtained experimental result is shown that the 35K or more degree from melting point brings 100% latent heat storage rate of W/O emulsion. It was clarified that the supercooling rate of dispersed water particles in emulsion shows the larger value than that of the bulk water. 相似文献
105.
Fabrication of optics by use of plasma chemical vaporization machining with a pipe electrode 总被引:1,自引:0,他引:1
Takino H Shibata N Itoh H Kobayashi T Yamamura K Sano Y Mori Y 《Applied optics》2002,41(19):3971-3977
We figure optical surfaces by plasma chemical vaporization machining (CVM) with a pipe electrode, in which an rf plasma generated at the electrode tip under approximately atmospheric pressure moves over the surfaces. We propose a shaping method in which the movement of plasma on the surfaces can be determined. Flat and aspheric surfaces are successfully figured with the desired peak-to-valley shape accuracy of 0.1 microm. The root-mean-square roughness of the resultant surfaces is at the subnanometer level. These results confirm that the plasma CVM and the shaping method have the capability to fabricate optics with high accuracy. 相似文献
106.
An anodic alumina supported Ni–Pt bimetallic plate-type catalyst was prepared by a two-step impregnation method. The trace amount 0.08 wt% of Pt doping efficiently suppressed the nickel particle sintering and improved the nickel oxides reducibility. The prepared Ni–Pt catalyst showed excellent performance during steam reforming of methane, kerosene and ethanol under both 3000 h stationary and 500-time daily start-up and shut-down operation modes. Self-activation ability of this catalyst was evidenced, which was considered to be resulted from the hydrogen spillover effect over Ni–Pt alloy. In addition, an integrated combustion-reforming reactor was proposed in this study. However, the sintering of the alumina support is still a critical issue for the industrialization of Ni–Pt catalyst. 相似文献
107.
Sea urchin shells are generally discarded as food waste after removal of edible gonads, although they possess significant amount of polyhydroxylated naphtoquinone pigments having potent antioxidant property. In this study, separation and quantification of the pigment mixtures from purple sea urchin shells were performed using a C18 reversed-phase HPLC with isocratic elution of 50% mixture of solvent (A) formic acid: water (0.1: 100, v/v) and solvent (B) MeOH: acetonitrile (5: 9, v/v) at a flow rate of 0.5 mL/min. The pigment mixtures were separated into four major peaks in 30 min, which assumed to be spinochromes A, B and C and echinochrome A on the basis of UV-Vis absorption spectra obtained by a diode array detector. LC-MS analysis also supported these results by producing the predominant base peaks at m/z 221.1, 279.1, 265.1, and 263.1 corresponding to the pseudomolecular ions [M-H]− of the respective compounds. The HPLC method also showed good correlations (r2 > 0.98) between injected amounts of these pigments and peak areas recorded at 340 and 520 nm. These results indicated that the HPLC method developed in this study would be applicable for the separation and quantification of these major pigments in sea urchin shells. 相似文献
108.
Takeshi Miura Takaaki Kaiga Takeshi Shibata Hiroaki Katsura Katsubumi Tajima Hideo Tamamoto 《IEEJ Transactions on Electrical and Electronic Engineering》2014,9(6):697-699
In this paper, we propose a novel method to extract keyframes from motion capture data. A hybrid approach, which combines a curve‐simplification algorithm with an initialization procedure including principal component analysis, is adopted. The developed method automatically extracts an appropriate number of keyframes at high speed without performance degradation. Experimental results prove the effectiveness of the present method. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
109.
Masahiro Tajima Miki Niwa Yasushi Fujii Yutaka Koinuma Reiji Aizawa Satoshi Kushiyama Satoru Kobayashi Koichi Mizuno Hideo Ohuˆchi 《Applied catalysis. B, Environmental》1997,12(4):1418
The decomposition of chlorofluorocarbons (CFCs) in the presence of water was examined over a variety of solid acid catalysts. The TiO2ZrO2 catalyst was found to have the highest activity and longest life among the catalysts examined. The activity of the TiO2ZrO2 catalysts depended upon the content of TiO2. At the contents of TiO2 from 58 to 90 mole%, the TiO2ZrO2 catalysts exhibited high activity, and these catalysts were proven to contain TiZrO4 crystal. From the study of the XRD peak intensity of the TiZrO4 crystal, it was highest on the TZ-58 which contained 58 mole% of TiO2, and decreased with increasing the content of TiO2. Furthermore, the conversion of CFC113 measured at 673 K was highest at TZ-58, and decreased gradually with increasing TiO2 content. Therefore, the TiZrO4 crystal influences the activity of decomposition of CFC113. However, the TiO2ZrO2 catalyst was gradually deactivated during the reaction due to the elimination of titanium atoms. A good relationship was found between the activity on TiO2ZrO2 catalyst and bond energy of CCl in the compounds of chlorofluorocarbons and hydrochlorocarbons, suggesting that the rate controlling step was the cleavage of CCl bond. 相似文献
110.
Hideo Yamauchi Junichi Ikejiri Fumio Sato Hiroyuki Oshita Tsuyoshi Honma Takayuki Komatsu 《Journal of the American Ceramic Society》2019,102(11):6658-6667
In recent years, the expansion of demand for lithium ion batteries has resulted in soaring prices of the constituent resources. From the viewpoint of safety, studies on all-solid-state batteries are actively being carried out. In this study, we succeeded in driving all-solid-state batteries derived from nontoxic oxide glasses at room temperature without requiring scarce resources such as lithium and cobalt. The main structure of the ceramic batteries with a simple structure in which Na2FeP2O7 crystallized glass and β″-alumina solid solution are joined by pressureless cofiring at 550°C. During the crystallization of Na2O-Fe2O3-P2O5 glass, fusion with the β″-alumina solid solution is achieved. Reversible charge and discharge of 80 mAh/g were achieved at room temperature. It is not necessary to apply pressure during cell preparation or the use of the batteries. Furthermore, the strong junction at the cathode and electrolyte interface does not peel off during charge and discharge over a long period of 623 cycles. Ex situ X-ray photoelectron spectroscopy revealed partial Fe4+ induction and a reversible charge and discharge reaction even after overcharging to 9 V. It was demonstrated that Na2FeP2O7 is very stable against overcharging to 9 V. 相似文献