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81.
The laminate method for studying the permeability and diffusivity of moistened cellophane to gases is described and the humidity dependence of the transport parameters for H2, He, and Ne is presented. In the relative humidity region of about 0% to 60%, a small increase in the permeability was observed, which is caused by a comparatively small increase in the diffusivity owing to the plasticizing effect of sorbed water and a decrease in the solubility. On the other hand, an extremely large increase in the permeability observed in the relative humidity region above 60% is mainly based on the diffusion coefficient of gas enhanced by the swelling effect of sorbed water. The presence of a minimum in the solubility–relative humidity curves has been confirmed and is discussed. 相似文献
82.
Shoichi Nasu Takaaki Tanifuji Katsuya Uchida Kenji Noda Toshimasa Kurasawa Tadashi Takahashi Masahiko Isshiki Takejiro Miyauchi Kohji Tanuma Fumio Sasajima 《Journal of Nuclear Materials》1980,91(1):121-126
The center temperature of Li2O pellets under neutron irradiation was measured using an encapsuled pin. The surface temperatures of the pellets and the pellet/cladding heat transfer coefficients were estimated on the basis of the well-known conductivity integral. 相似文献
83.
The environmental stability in distilled water and the failure mechanism of cathodically chromated tin, lead, and lead/tin alloy joints bonded with an ethylene–acrylic acid copolymer have been investigated by T-peel tests and ESCA and SEM analyses of the fractured surfaces. The peel strength of chromated lead/tin alloy joints and of both untreated and chromated tin joints is kept unchanged with water immersion, whereas that of untreated lead/tin alloy joints and of both untreated and chromated lead joints decreases rapidly with water immersion. ESCA and SEM observations show that lead/tin alloy surfaces consist of both lead and tin phases and that the tin phase interface deteriorates gradually with water immersion after premature deterioration of the lead phase interface. The stabilization effect of chromate treatments for lead/tin alloy joints is due to retardation of the underfilm corrosion of the tin phase. 相似文献
84.
85.
Kazuhisa Shobu Eiji Tani Morito Akiyama Tadahiko Watanabe 《Journal of the American Ceramic Society》1996,79(2):544-546
High-temperature fracture behavior of melt-infiltrated SiC-Mo(AI,Si)2 composites was studied. The composites exhibited moderate strength up to ∼1600°C under a fast loading rate. The softening of the Mo(Al,Si)2 phase determined dominantly the temperature over which the strength decreased. The composite with finer microstructure revealed a higher level of strength over the whole temperature range. At 1580°C, however, the composites revealed distinct strength degradation at a reduced loading rate. 相似文献
86.
87.
Pulsed laser annealing was carried out for n-type semiconducting GaAs in air, 1 bar nitrogen, 1 bar argon, and 100 bar argon gas ambiences. Depth profiles of the atomic ratio
measured by SIMS indicate that pulse annealing in air results in As loss and penetration of oxygen into the crystal, both of which affect dopant redistribution and deteriorate electrical properties of the annealed layer. High electrical activity (100%) and electron mobilities were achieved for high-dose implants of Si+ (1 × 1015 cm−2) by pulsed laser annealing in the high-pressure ambience. 相似文献
88.
Fumio Fujii 《International journal for numerical methods in engineering》1981,17(12):1843-1859
For plate bending analysis, both discrete and non-discrete mixed methods are presented by using spline functions in the Hellinger-Reissner variational principle. Piecewise spline interpolation with local supports and overall spline interpolation with boundary knots are applied to each of two mixed functionals. The prescribed boundary conditions can be considered by multiple boundary knots. The convergence behaviour of the mixed methods presented is studied. Numerical examples show that a high degree of accuracy can be obtained due to continuous properties in the high derivatives of the employed shape functions. The proposed mixed methods are found to be very competitive with other numerical methods for plate bending problems. 相似文献
89.
Khan JS Imamoto Y Yamazaki Y Kataoka M Tokunaga F Terazima M 《Analytical chemistry》2005,77(20):6625-6629
A new type of biosensor is presented for the first time. This method is based on the diffusion measurement in the time domain by the transient grating method. As the first demonstration of this new method, various intermolecular interactions with a reaction intermediate of photoactive yellow protein, such as the protein-protein interaction, protein-DNA interaction, and protein-small molecule binding are detected. The characteristic advantages and limitations are summarized. 相似文献
90.
Previously it was found that casting could be carried out efficiently without strain formation by radiation-induced polymerization of glass-forming monomers. Two types of strain were observed in casting: thermal stream type, which was studied previously, and remained stress type. In this report, the effect of various factors on the formation of remaining stress-type strain in radiation-induced casting polymerization was studied. It was found that the molecular weight of prepolymer did not affect strain formation, while prepolymer concentration and viscosity of the system had a serious influence on strain formation. It could be deduced that this type of strain formed as a result of remaining inner stress due to poor relaxation of the shrinking stress. It was realized that less volume shrinkage of glass-forming monomers accompanying casting polymerization reduced the strain formation of this type in radiation-induced casting polymerization at low temperatures. 相似文献