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排序方式: 共有466条查询结果,搜索用时 31 毫秒
71.
Isao Kanda Kiyoshi Uehara Yasuo Yoshikawa Tazuko Morikawa 《Journal of Wind Engineering & Industrial Aerodynamics》2006,94(9):639-658
By a reduced-scale model in a wind tunnel, we investigate the dispersion behavior of exhaust gas from automobiles. Two types of vehicles are considered, a passenger car and a small-size truck. Tracer gas experiments show that the exhaust gas dispersion is enhanced significantly by the vehicle wake compared to the case when the vehicle body is absent. The passenger car and the truck promote dispersion in the horizontal and the vertical direction, respectively. The wake field is analyzed by particle image velocimetry (PIV), and the distribution of the mean and the fluctuation fields is found to conform to the concentration field of the exhaust gas. The buoyancy of the exhaust gas has minor effect except on the vertical spread behind the truck whose wake flow amplifies the vertical displacement generated near the pipe exit. 相似文献
72.
Takuya Uehara Hiroshi Kitahara Hideshi Naka Shigeru Matsuyama Tetsu Ando Hiroshi Honda 《Journal of chemical ecology》2016,42(6):517-522
Recent work has suggested that hawk moths share pheromone components but are sexually separated by qualitative and quantitative differences in their pheromone blends. During field assays on the sex pheromones of other species, a diurnal hawk moth, Neogurelca himachala sangaica (Lepidoptera: Sphingidae), was frequently captured, but the composition of the sex pheromone of this species was not known. Analysis of hexane extracts of the pheromone glands of calling female by gas chromatography (GC) using an electroantennographic detector (EAD) revealed two components that elicited EAD responses from male moth antennae. These components were identified by their mass spectra and retention indices on two GC columns as (10E,12Z)-10,12-hexadecadienal (E10,Z12–16:Ald) and a trace of its (10E,12E)-isomer (E10,E12–16:Ald) in 98:2 ratio. In field experiments, E10,Z12–16:Ald alone attracted male moths, and addition of E10,E12–16:Ald significantly reduced the attractiveness, even at the naturally-occurring ratio. Analysis of the data using a generalized linear mixed model showed that E10,Z12–16:Ald positively contributed to attractiveness, whereas E10,E12–16:Ald did so negatively, and it was concluded that the sex pheromone of N. himachala sangaica consists solely of E10,Z12–16:Ald, bombykal. The negative effect of E10,E12–16:Ald on attractiveness could promote the species-specificity of this single-component pheromone system. 相似文献
73.
Experiments were conducted to determine the effects of impeller clearance, impeller diameter, and other operating variables on the minimum agitation speed for off-bottom solid suspension in agitated vessels, Njs, for disc turbines (DTs) and flat-blade turbines (FBTs). Only data for which the impellers produced recirculation flows above and below the impeller (the so-called “double-eight” flow pattern) were considered. Regression equations for Njs were obtained, in which explicit terms for impeller clearance and vessel diameter-to-impeller diameter ratio (T/D) were included. Modified Zwietering equations (Zwietering, 1958) were also obtained, in which Zwietering's parameter S was mathematically expressed as a function of vessel diameter-to-impeller clearance ratio and T/D ratio. When used together with the correlations of Armenante and Uehara Nagamine (1998) for impellers close to the vessel bottom, the equations presented here can be used to calculate Njs for DTs and FBTs for any typical impeller clearance. 相似文献
74.
Taizo Kojima Hideo Nakata Motohiko Kawagishi Taku Uehara 《Electrical Engineering in Japan》1998,123(1):32-42
This paper presents a framework for constructing databases for supervisory control systems. The proposed framework utilizes a generation-based approach and object-oriented framework libraries. In this framework, a database is designed for the target system from a design template, and the software for the database system is generated from the database design. The generated database system includes a domain-specific object system and a diagram and plant data editor, which provides effective data input functions. © 1998 Scripta Technica, Electr Eng Jpn, 123(1): 32–42, 1998 相似文献
75.
This paper proposes a method of maintaining the stability of robotic manipulators with network connection which are doing cooperative tasks. Such robotic manipulator systems have many possibilities, but they sometimes fall into unstable states due to double connection, that is, mechanical and informational connection. To avoid such unstable oscillations, the proposed method utilizes a kind of torque limiter and a notch filter. © 1997 Scripta Technica, Inc Electr Eng Jpn, 121(2): 47–53, 1997 相似文献
76.
Umemura T Hotta H Abe T Takahashi Y Takiguchi H Uehara M Odake T Tsunoda K 《Analytical chemistry》2006,78(21):7511-7516
A sensitive and fast-responsive evanescent wave absorption sensor has been constructed for pH measurements in highly acidic ranges. This sensor is based on a pH-dependent color change of protoporphyrin IX (PPIX). For the sensitive detection, a visible attenuated total reflection spectrometer with a slab optical waveguide (SOWG) was laboratory-made, and the guiding layer surface was modified with a PPIX-immobilized acrylamide-based thin membrane. The sensing membrane with a thickness of approximately 1 mum was directly fabricated on the SOWG glass surface by copolymerization of acrylamide, N,N'-methylene bisacrylamide, and PPIX in the narrow space confined by a cover plate. PPIX possesses two double bonds in its structure, and so it can be covalently incorporated into the membrane. The response characteristics of the PPIX-immobilized optode membrane were explored using aqueous solutions with different concentrations of HNO(3) or HCl. The optode membrane provided characteristic Soret band absorption spectra depending on the hydrogen ion concentration; the absorbance at 410 nm increased with increasing the concentrations in the range of 0.15-2 M, corresponding to the range of pH -0.3 to 0.8. The absorption signal reached 90% of its final value within 10 s, while the absorption signal was quite readily returned to background level simply by passing 2 mL of distilled water through a flow cell with a volume of 16.5 muL placed on the SOWG. Due to the rapid response and reversibility, this sensor could be operated in a flow-through mode as well as in a conventional static mode, where deionized water was conveniently used as a carrier and conditioning solution. In terms of the stability and precision, this sensor showed no significant change in response even after 100 assays and after being stored in a dry condition for over 6 months. Relative standard deviations for 10 replicate measurements were less than 1.8% in the linear range, and the detection limit calculated from 3 times of the standard deviation was 0.02 pH unit. 相似文献
77.
Jun Oshitani Tetsuya Kawahito Mikio Yoshida Kuniaki Gotoh George V. Franks 《Advanced Powder Technology》2012,23(1):27-30
In this study, the influence of the fluidized bed height on the float–sink of different sized spheres in a gas–solid fluidized bed was investigated. Fluidized beds with heights h = 200, 150, 100 and 50 mm were prepared using a cylindrical column of inner diameter = 290 mm and a mixture of zircon sand and iron powder as the fluidized medium. Float–sink experiments were carried out using density adjusted spheres of diameter Dsp = 40, 30, 20 and 10 mm. It was found that the float–sink performance at Dsp ?20 mm is not affected by the height of the bed, and the sharpness of separation (the density range where spheres neither float nor sink completely) is less than or equal to 200 kg/m3. In the case of Dsp = 10 mm, the sharpness of separation is a larger value (1100 kg/m3 at h = 200 mm), whereas it decreases with decreasing h and is 400 kg/m3 at h = 50 mm. The fluctuation of the surface height of the fluidized bed was visually recorded. The fluctuation is reduced by reducing h. The fluctuation vs. h correlates with the sharpness of separation at Dsp = 10 mm vs. h. These results indicate that the dry float–sink separation of smaller sized spheres is improved as the fluctuation of fluidized bed surface is decreased by reducing the fluidized bed height. 相似文献
78.
Ohya Y Miyoshi N Hashizume M Tamaki T Uehara T Shingubara S Kuzuya A 《Small (Weinheim an der Bergstrasse, Germany)》2012,8(15):2335-2340
Divalent DNA-AuNP (gold nanoparticle) conjugates comprising two DNA strands at diametrically opposed positions are prepared. Highly linear 1D and tetragonal lattice-like 2D AuNP arrays are constructed using the conjugates and DNA assemblies based on T- and double-crossover motifs and the Holliday junction. 相似文献
79.
Masanori Hara Kaori YudouEmiko Kinoshita Kayoko OkazakiKazuyoshi Ichinose Kuniaki WatanabeMasao Matsuyama 《International Journal of Hydrogen Energy》2011,36(19):12333-12337
To study the alloying effects on ZrMn2-H system, thermodynamic properties of Zr(Mn1−xCox)2 hydride were measured by volumetric method. ZrMn2 gave a single plateau region in the pressure-composition isotherm. On the other hand, double plateaus were clearly observed in Zr(Mn0.7Co0.3)2 and Zr(Mn0.6Co0.4)2-H systems. The appearance of the double plateau characteristics would be explained in view of the hydrogen binding in the tetrahedral occupation sites in Zr(Mn1−xCox)2. Since the hydrogen binding in the tetrahedral 2ZrMnCo site would be less stable than that in the 2Zr2Mn site, the equilibrium pressure increases with increasing cobalt content. The appearance of the first plateau was ascribed the increase in the bonding of Mn-H in 2Zr2Mn site adjoining the 2ZrMnCo site. 相似文献
80.
Masahiro Shikano Hironori KobayashiShinji Koike Hikari SakaebeYoshiyasu Saito Hironobu HoriHiroyuki Kageyama Kuniaki Tatsumi 《Journal of power sources》2011,196(16):6881-6883
18650-type cylindrical cells using LiNi1/3Mn1/3Co1/3O2 (NMC) and hard carbon as positive and negative electrode material, respectively, were fabricated and degraded by cycle tests. The capacity of the cells remained more than 95% and 85% after cycle tests at 25 and 50 °C, respectively. After the cycle tests, Li-deficient cubic phase was observed on the surface of NMC. This phenomenon should be related to the degradation mechanism of this type of cell. 相似文献