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91.
Hideki Harano Kenichi Kinoshita Koji Yoshii Toru Ueda Shunsuke Okita Mitsuru Uesaka 《Journal of Nuclear Materials》2000,280(3):255-263
As a promising tool for ultrafast material analyses, we propose to utilize the X-ray pulse which may be generated in a quite simple manner using subpicosecond electron linacs. The properties of the X-ray were numerically studied with the EGS4 code. Verification of the X-ray generation was also conducted at the Nuclear Engineering Research Laboratory (NERL) linac and clear diffraction patterns of characteristic X-ray were obtained for typical single crystals. 相似文献
92.
We propose a new geometric method of IR factorization in sector decomposition. The problem is converted into a set of problems in convex geometry. The latter problems are solved using algorithms in combinatorial geometry. This method provides a deterministic algorithm and never falls into an infinite loop. The number of resulting sectors depends on the algorithm of triangulation. Our test implementation shows smaller number of sectors comparing with other existing methods with iterations. 相似文献
93.
K. Friedrich E. Ueda H. Kamo M. Evstatiev B. Krasteva S. Fakirov 《Journal of Materials Science》2002,37(20):4299-4305
Microfibrillar reinforced composites (MFC) comprising an isotropic matrix from a lower melting polymer, i.e., low density polyethylene (LDPE), reinforced by microfibrils of a higher melting polymer, recycled from bottles, i.e., poly(ethylene terephthalate) (PET), were processed under industrially relevant conditions via injection molding in a weight ratio of PET/LDPE = 50/50. Dog bone samples with MFC structure were characterized by means of scanning (SEM) and transmission (TEM) electron microscopy. SEM observations on cryogenic fracture surfaces show an isotropic LDPE matrix reinforced by more or less randomly distributed PET microfibrils. By means of TEM on stained ultrathin slices one observes the formation of transcrystalline layers of LDPE matrix on the surface of the PET microfibrils. In these layers the crystalline lamellae are aligned parallel to each other and are placed perpendicularly to the fibril surfaces. This is in contrast to the bulk matrix where the lamellae are quasi-randomly arranged. 相似文献
94.
Since diamonds indicated low or negative electron affinity, they have been expected to be high performance electron emitters. New diamond electron sources have been developed, which are configured for electron beam instruments such as electron beam lithography systems and electron microscopes. As a result of thermionic emission evaluations, an electron emission current of practical level (116 µA at 600 °C) was obtained. The energy spread of an electron beam generated by thermionic emission was measured as 0.23 eV (FWHM), the value of which was lower than those of a lanthanum hexaborate (LaB6) cathode and a zirconium oxide/tungsten (ZrO/W) cathode measured together. The result of field emission evaluations, a practical beam current (459 pA) and stability (6% rms for 10 h) for scanning electron microscope (SEM) was achieved. The energy spread of a high-current electron beam of over 200 pA generated by field emission from a diamond emitter reached about the same as that of a cold field emission cathode made of tungsten. A scanning electron micrograph (SEM) with a diamond electron source having a tip of submicron order allowed measurement a resolution of 5 nm. It was found that unprecedentedly high-current and high-convergence electron sources could be generated by using diamonds. 相似文献
95.
Yukitoshi Takeshita Takuya Kamisho Seizo Sakata Takashi Sawada Yoshikazu Watanuki Ryuichi Nishio Toshinobu Ueda 《Journal of Coatings Technology and Research》2013,10(4):503-514
To improve alkaline resistance, a newly mixed powder coating film using thermoplastic polyethylene terephthalate (PET) was investigated. Two kinds of polyvinyl butyral (PVB) and two kinds of polyamide (PA) were chosen as the secondary polymer. The melting temperatures (T ms) of these materials were lower than that of primary PET polymer so the mixed powder coating was able to form a dual phase film through a fluidized bed coating process. Microscope and Fourier transform infrared spectroscopy (FTIR) observations revealed that the dual phase structure was indeed successfully formed and there was a secondary layer over the entire surface area of the film. This mixed powder coating film significantly enhanced the alkaline resistance to an environment filled with NaOH solution at 40°C in which a secondary material would be effective in protecting the film. With regard to both alkaline resistance and film formability, PET/PVB was superior to the PET/PA mixture. 相似文献
96.
Phase relations for the Al2O3-CaF2-SiO2 system were investigated from 1673 to 1723 K. The hotfilament technique was applied to observe a two-liquid region and liquidus
for the ternary system. The liquidus saturated with SiO2 was investigated at 1673 K by using the hot-filament technique and the chemical equilibrium technique. In this system, the
addition of Al2O3 to the CaF2-SiO2 system reduces the congruent temperature. A small substitution of Al2O3 for CaF2 increases the solubility of SiO2, namely, if the region of liquid phase could be enlarged. These results suggest that Al2O3 would be an effective substitute of CaF2 in slag for steelmaking. 相似文献
97.
Takase F. Tominaga M. Ueda Y. Temma T. Genji T. Oku K. Hira T. Ashizawa A. 《Energy Conversion, IEEE Transaction on》1997,12(2):143-150
This paper deals with a harmonic compensation method using a synchronous machine with resonant field circuits. Harmonics have become one of the major problems in power systems and a lot of methods of harmonic suppression have been studied. The authors have proposed a new method of harmonic suppression using a synchronous machine excited with the 6th harmonic current. This paper shows that armature inductances for the 5th or 7th harmonics decrease when the field circuits are connected to capacitors resonating at the 6th harmonic. The variations of armature impedances are explained theoretically by Park's equations. The optimal capacitances are selected so as to resonate with field inductances for the short-circuited armature. The experiments to suppress the 5th and 7th harmonics using the synchronous machine are successful 相似文献
98.
Design of the Kernel Language for the Parallel Inference Machine 总被引:1,自引:0,他引:1
99.
The present authors pointed out in the previous paper [1] that the implicit SMAC scheme is quite efficient and non-staggered grid arrangement can decrease the computational effort and save the storage memory which is very important to the direct numerical simulation (DNS) of complicated 3-D flow fields. But using non-staggered grid arrangement, the pressure field oscillation (PFO) ordinarily occurs and also, the pressure on the solid walls including sharp corners need to be prescribed directly as the pressure boundary conditions.
In this paper, a new interpolation method, which is a modification to Cheng and Armfield's interpolation formulation, is presented in order to completely prevent PFO from occurring, Moreover, a more accurate specification method of wall pressures and special treatment of pressures at sharp corners are proposed. To test the new methods proposed, the DNS of flow past a square cylinder and flows over backward-facing steps, which are typical of the flow fields with sharp corners, is made using the implicit SMAC scheme combined with these methods. The calculated results are compared with the previous experimental and numerical data and show good agreement with them. 相似文献
In this paper, a new interpolation method, which is a modification to Cheng and Armfield's interpolation formulation, is presented in order to completely prevent PFO from occurring, Moreover, a more accurate specification method of wall pressures and special treatment of pressures at sharp corners are proposed. To test the new methods proposed, the DNS of flow past a square cylinder and flows over backward-facing steps, which are typical of the flow fields with sharp corners, is made using the implicit SMAC scheme combined with these methods. The calculated results are compared with the previous experimental and numerical data and show good agreement with them. 相似文献
100.