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排序方式: 共有1385条查询结果,搜索用时 15 毫秒
1.
K. Mizutani 《Journal of Materials Science》1993,28(8):2178-2182
Transparent epoxy resins modified with liquid chloroprene rubber (LCR), containing in a category of rubber-toughened resin were found. Transparency and toughness characterization of the modified epoxy resins were investigated as a function of LCR content. Epoxy resins modified with 0–10 vol % LCR showed complete phase-separation microstructure. However, these modified resins were transparent, because the refractive index of LCR was compatible with that of the epoxy resin matrix at room temperature. On the other hand, it was observed that above 10 vol % LCR, a certain amount of LCR dissolved into the epoxy matrix. In this case, the glass transition temperature decreased with increasing LCR content. It was also found that the critical stress intensity factor, K
c, of the modified epoxy resins exhibited a maximum between 10 and 15 vol % LCR. 相似文献
2.
In this article, we consider a flexible beam with a rigid body, of which the bending vibration and the torsional vibration are decoupled. Therefore we need two control motors to suppress the vibrations. Each set of dynamic equations is treated in the form of an appropriate Hilbert space. A stabilizing feedback control law of each rotation motor will be established on the basis of modal analysis. A set of experiments has been carried out, and the results demonstrate the effectiveness of the dynamic model and the proposed control law. © 1994 John Wiley & Sons, Inc. 相似文献
3.
Yoshiyuki Uno Akira Okada Kensuke Uemura Purwadi Raharjo Toshihiko Furukawa Kosaku Karato 《Precision Engineering》2005,29(4):171-455
A new finishing process for metal molds by large-area electron beam (EB) irradiation is proposed in this study. In the large-area EB irradiation equipment used here, an EB with high-energy density is irradiated without focusing the beam, and so the EB with a maximum diameter of 60 mm can be used for melting or evaporating metal surface instantly. Experimental results show that the surface roughness decreases from 6 μmRz to less than 1 μmRz in just a few minutes under proper machining conditions. The corrosion resistance of metal mold surface also could be greatly improved by large-area EB irradiation. Furthermore, the surface roughness of tilting surface close to 90° could be well improved. Therefore, large-area EB irradiation method has a possibility to become a high-efficiency finishing process for metal molds. 相似文献
4.
The microporous polypropylene sheets were prepared by biaxially stretching polypropylene sheets containing CaCO3 filler (particle size, 0.08–3.0 μm), when the CaCO3 filler content was 59% by weight and the stretching ratio was 2.8 × 1.8. The microstructure of the sheets were investigated in relation to the CaCO3 particle size by a N2 gas permeation method. (1) Effective porosity increases with decreasing mean particle size of filler. (2) The tortuosity factor of the pore is in the range of 25–40 and becomes relatively smaller with decreasing mean particle size of filler. (3) The equivalent pore size becomes relatively smaller with decreasing mean particle size of filler. 相似文献
5.
The MOBILE is a logic gate exploiting the monostable-bistable transition of a circuit that consists of two resonant tunneling transistors connected in series. It has several advantages including multiple inputs and multiple functions. This paper describes the output characteristics of multiple-input MOBILE's and discusses their applications. For a two-input MOBILE, it is demonstrated that both NAND and NOR operations are possible with the appropriate control voltage. This implies the possibility of a variable function logic gate. Furthermore, the threshold logic operations for a weighted sum of input signals are demonstrated for a three-input MOBILE with a weight ratio of 4:2:1. The applications of MOBILE's in parallel processing architectures such as cellular automata and cellular neural networks are discussed based on the above results. Circuit simulations using a simple model of resonant tunneling transistors successfully reproduce the basic characteristics of MOBILE's, and demonstrate the usefulness of MOBILE's in such applications 相似文献
6.
Nobuo Ishizawa Atsushi Saiki Takeshi Yagi Nobuyasu Mizutani Masanori Kato 《Journal of the American Ceramic Society》1986,69(2):18-C-
Crystals of yttria partially stabilized zirconia were grown by the arc-image floating-zone technique and studied by transmission electron microscopy. Crystals annealed at 1700°C consist of tetragonal precipitates and a cubic matrix. The platelike domains in a precipitate are twin-related tetragonal variants stacked alternately parallel to the (011) twin plane. The axial relations between the tetragonal precipitate and the cubic matrix are [100]tetragonal |[100]cubic , [011]tetragonal |[011]cubic . 相似文献
7.
Preparation of spherical fine ZnO particles by the spray pyrolysis method using ultrasonic atomization techniques 总被引:1,自引:0,他引:1
Tian-Quan Liu Osamu Sakurai Nobuyasu Mizutani Masanori Kato 《Journal of Materials Science》1986,21(10):3698-3702
An ultrasonic atomizer was used in the spray pyrolysis method to prepare fine, spherical and uniform ZnO particles. Almost spherical particles were obtained successfully which had a mean particle size of 0.15 m and had a very narrow particle size distribution. By using alcohol as the solvent, it was found that the particles do not have hollow shell layers which could usually be observed in the spray pyrolysis process by using water as the solvent. The morphology of the ZnO particles was strongly affected by the concentration of the starting solution. 相似文献
8.
Takashi Ogihara Tadashi Ikemoto Nobuyasu Mizutani Masanori Kato Yukuaki Mitarai 《Journal of Materials Science》1986,21(8):2771-2774
The Ta2O5 powders synthesized by the hydrolysis of tantalum pentaethoxide, Ta(OC2H5)5 in alcoholic solution were monodispersed fine oxide particles, which were a uniform, spherical shape, non-agglomerate, and had a narrow size distribution. They grew to 1.2m after ageing for 1 h after hydrolysis. Powder X-ray diffraction and differential thermal analysisthermogravimetric analysis showed the particles were amorphous and hydrated. These particles lost the water at 290° C and gave well-crystalline Ta2O at 740° C. Throughout these thermal processes, the particle morphology was kept almost the same. 相似文献
9.
Copoly(amide-ethers) containing two types of tertiary amine units were made as antistatic modifiers for poly(ethylene terephthalate) (PET) fibers. The filaments of the copolymers were melt-spun and reacted with three alkylating agents in order to quaternize the tertiary amine into a sulfo-betaine, a carbobetaine, and an ammonium ion. The apparent electric resistivity of the filaments was greatly reduced by this reaction, being in the range of 106 to 108 Ω/cm. However, because these quaternized copolymers incurred decomposition during blend spinning with PET, a blend PET fiber containing one type of copoly(amide-ether) was melt-spun and subjected to quaternization of the amino groups as well as to surface crosslinking with various alkylating and epoxy agents. The quaternized blend fibers obtained showed improved antistatic properties compared with the original blend fiber. Particularly, the fibers crosslinked with epoxy compounds were found to have the best antistatic properties that had ever been attained with this type of modification. The antistatic properties were retained even after dyeing, because both hydrophilic and ionic groups had been effectively immobilized on the surface. Since this quaternization and crosslinking could be conducted on-line with spinning and drawing within a short reaction time, this modification technique is called “spin-finishing method”, which should be superior to the conventional methods in terms of cost performance and productivity. 相似文献
10.
Takeshi Yagi Kazuo Shinozaki Nobuo Ishizawa Nobuyasu Mizutani Masanori Kato Akihiko Tsuge 《Journal of the American Ceramic Society》1988,71(7):334-C
The thermal diffusivity of AlN ceramics was significantly decreased by the addition of SiO2 . The AlN ceramics with 4 wt% SiO2 could not be densified by pressureless sintering in the temperature range 1400° to 1800°C. The thermal diffusivity of these samples was very low because of their porous structure. The AlN ceramics containing 2, 4, and 8 wt% SiO2 were densified by hot-pressing and also had low thermal diffusivity. In these samples, the grains of the 27R polytype that resulted from the reaction between AlN and SiO2 were dispersed, obstructing the conduction of heat. The relation between the amount of 27R polytype and the thermal diffusivity of the AlN ceramics was determined. 相似文献