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81.
This study experimentally investigated the possibility of stable burning conditions of liquid fuel inside a narrow tube using an electrospray technique without external heating or a catalyst. The mixture of 30% volume ethanol and 70% volume n-heptane was used as a liquid fuel atomized by the electrospray method with single capillary-ring extractor-mesh collector electrode configuration placed inside a quartz glass tube with an inner diameter of 3.5 mm. A stable flame was established inside the narrow tube without wall wetting within a certain range of equivalence ratio for a fuel flow rate of 1 mL/h. This study confirmed that the role of the mesh as the collector was very important in establishing a stable flame inside the narrow tube. If the fuel flow rate was sufficiently large, wall wetting occurred and eventually stable burning stopped. 相似文献
82.
Structural Changes of Scandia-Doped Zirconia Solid Solutions: Rietveld Analysis and Raman Scattering 总被引:1,自引:0,他引:1
Hirotaka Fujimori Masatomo Yashima Masato Kakihana Masahiro Yoshimura 《Journal of the American Ceramic Society》1998,81(11):2885-2893
Powder X-ray diffractometry (XRD) and Raman scattering measurements were used to study the structural changes of compositionally homogeneous metastable ZrO2 solid solutions induced by ScO1.5 doping. The crystal structures of monoclinic, tetragonal, cubic, and rhombohedral (Sc2 Zr7 O17 , ß-phase) solid-solution phases have been refined by using the Rietveld analysis of the XRD data at room temperature of arc-melted ZrO2 - X ScO1.5 ( X = 0, 2, …, 20, and 22 mol%) samples. The results can be interpreted as indicating that the structures of the monoclinic and tetragonal phases approach those of the tetragonal and cubic phases, respectively, by ScO1.5 doping. Raman scattering, as well as XRD, was useful to investigate the phase assemblage. Moreover, we could obtain Raman spectra of the ß-phase probably for the first time. 相似文献
83.
84.
Hiroi Masato Hojo Masayuki Hashimoto Yukio Abe Yoshikazu Dote Yasuhiko 《Industrial Electronics, IEEE Transactions on》1986,(2):110-113
A methodology of discontinuous feedback and continuous feedforward control is developed to achieve accurate decoupled tracking in a class of nonlinear, time varying systems in the presence of disturbances, parameter variations and nonlinear dynamic interactions. The method is based on an improved variable structure control with a sliding mode. 相似文献
85.
It is reported that laser-processing is effective to repair the heat checks, which are fine shallow cracks on a surfaceof die-casting dies. 相似文献
86.
Masato Yamamura Takatoshi NishioToshihisa Kajiwara Kitaro Adachi 《Chemical engineering science》2002,57(15):2901-2905
The ordered necklace-like or cellular pattern formation has been investigated for ternary polymer solutions in which primary and secondary phase separations were induced by the solvent evaporation. The patterns consisted of regular droplet arrays of various diameters, which arose in the pre-existing polymer phases via the secondary phase separation. The pattern formation was enhanced with increasing air velocity and ambient humidity, while it was suppressed with decreasing initial film thickness. The regular pattern was independent of surface wettability of the solid substrate. We ascribe the morphology change to the evaporation-induced surface tension driven convection, which re-arranged the droplet distributions from disordered to flow-induced ordered patterns. 相似文献
87.
Kisaragi Yashiro Masato Naito Yoshihiro Tomita 《International Journal of Mechanical Sciences》2002,44(9):1845-1860
Molecular dynamics simulations are conducted on the dislocation behavior at the apices and edges of cuboidal Ni3Al precipitate in a pure Ni matrix, or the idealized γ/γ′ microstructure in a Ni-based superalloy. A tensile simulation of the [001] direction is implemented with a periodic cell that has eight cubic precipitates in order to investigate the nucleation site of dislocation in the idealized microstructure with no defects other than the γ/γ′ interfaces. The effect of residual internal stresses on the stability of the interfaces is also discussed. Other simulations are conducted on the behavior of edge dislocations nucleated from a free surface and proceeding in the γ matrix toward γ′ precipitates under shear force. Dislocation pinning at γ′ precipitates, bowing-out in the γ channel, pile-up and nucleation of superdislocation in the γ′ precipitate are simulated and inspected in detail. Discussions on the size of the γ/γ′ microstructure and the sharpness of the edge of the γ′ precipitate are also presented. 相似文献
88.
Mizuki Ono Tsunehiro Ino Masato Koyama Akira Takashima Akira Nishiyama 《Solid-state electronics》2004,48(12):2191-2198
It is shown that propagation delay time in CMIS (complementary metal insulator semiconductor field effect transistor) inverters is strongly affected by dielectric constant nonuniformity in gate dielectrics caused by the phase separation in silicate films. Influences of such nonuniformity on load capacitance are studied by analytical calculations based on a physical model which takes polarization into account. It is newly found that load capacitances are affected by the phase separation in qualitatively different ways, depending on the average metal concentration of their dielectric films. An experimental result is compared with those calculations. Influences of such nonuniformity on current drivability are studied by 3-dimensional device simulations. It is also newly found that such nonuniformity affects load capacitance and current drivability in different ways, resulting in an increase in propagation delay time of CMIS inverters for all metal concentrations studied. An explanation of this phenomenon is given with physical considerations. 相似文献
89.
Nao-Aki Noda Akifumi Inoue Masato Nagawa Fumitaka Shiraishi 《International Journal of Pressure Vessels and Piping》2002,79(12):807-818
This paper deals with a new seal system between flange joints without using a gasket. This gasketless flange includes a groove and an annular lip that is machined in one of the flange rings which when removed being in contact with the other flange to form a seal line when the flanges are assembled. In this study, firstly, fundamental dimensions are examined for unplasticized polyvinyl chloride (PVC-U JIS) to obtain the best sealing performance. Then, the effects of material difference and flange nominal size upon the sealing performance of the new gasketless flange are investigated for two types of materials, 0.25% carbon steel (S25C JIS) and PVC-U. It is found that the critical internal pressure at which leakage appears is mainly controlled by the maximum stress at the annular lip for each material even if the flange nominal sizes are different. The gasketless flange made by PVC-U shows the higher critical internal pressure compared with the case of S25C if the same clamping forces are applied. The effect of stress relaxation for PVC-U on the sealing performance is also considered. Then, it may be concluded that this PVC-U gasketless flange as well as S25C has good sealing performance. 相似文献
90.