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81.
The purpose of this study was to characterize the oxide scales formed on various Cr-Si-Ni compacts at 1273 K in air and H2O-containing atmosphere by TEM. It was found that CrSi2-(5-20)mass%Ni compacts form double layer scales, consisting of an outer Cr2O3 layer and an inner SiO2 layer. The oxide scale changed from SiO2- to Cr2O3-based scale with an increase in the Ni concentration. However, it was observed that the oxide scale formed in H2O-containing atmospheres showed local SiO2 growth into the substrate. This result suggests that the inward oxidant diffusion promotes the local growth of SiO2 in the H2O-containing atmospheres. 相似文献
82.
Md. Nazrul Islam Keisuke Ando Hidefumi Yamauchi Nobuaki Hattori 《Holz als Roh- und Werkstoff》2009,67(2):129-133
Penetration of liquid by passive impregnation method for Douglas-fir (Pseudotsuga menziesii Franco), sugi (Cryptomeria japonica D. Don) and Japanese larch (Larix leptolepis Gordon) was studied. Effects of initial moisture content of sugi (16, 43 and 70% moisture content) on liquid penetration were also studied. Dried Douglas-fir (mc=14%) and sugi (mc=16%), and green Japanese larch (mc=45%) and sugi (mc=70%) were treated by passive impregnation method for penetration analysis. It was observed that dried sugi had the highest level of liquid penetration both in length (170 mm) and width (8 mm) for all measured sections followed by green sugi, green Japanese larch and dried Douglas-fir. In case of different initial moisture content, the highest absorption (624 kg/m3) and penetration (maximum 87 and 96% at cross and longitudinal surfaces, respectively) was observed for sugi having the lowest initial moisture content under the same passive impregnation conditions. Absorption and penetration decreased with the increase of initial moisture content for sugi. These results could help in designing incising pattern and density, as well as solving the problems related to high initial moisture content of wood for passive impregnation. 相似文献
83.
Measurements of the V–I characteristics of a solid polymer electrolytic (SPE) dehumidifier were done using a modified SPE
dehumidifier with four electrodes which included two electrodes to carry the main current and the other two electrodes to
measure the voltages applied to the electrical double layer, which are the boundary voltages between the electrodes and the
SPE membrane. The measured results were analyzed using the Butler-Volmer equation to examine the validity of the measurements.
The current flowing in the dehumidifier is produced by the decomposition of water near the anode. Therefore, under a steady-state
condition, the current should be proportional to the supply rate of water to the anode. On the other hand, a two-layer model
for the SPE dehumidifier presented in our previous article showed that the current flowing in the dehumidifier was roughly
proportional to the water content in the vicinity of the anode. These results were introduced for interpretation of the V–I
measurements of the SPE dehumidifier. It was concluded that the dehumidifier current was expressed in the form of a Butler-Volmer
equation as a function of the electrode boundary voltages which were the voltages across the boundary between the electrodes
and the SPE membrane. An experimental formula for the current under a steady-state condition was developed as a function of
the water content near the anode and the boundary voltages. 相似文献
84.
Both President Peter Reynolds and Secretary General Glenn Stout attended the IWRA Regional Seminar on Water Quality and its Management in New Delhi, India on December 10–11, 1985. Over 100 members and fellow water scientists and administrators attended. Leading Indian water authorities participated in the program. We reproduce here the inaugural address by Shri B. Shankaranand, Union Minister for Water Resources, and a summary of the Conclusions and Recommendations. 相似文献
85.
86.
The radiation characteristics of a curl antenna excited by an L-wire are presented. The frequency bandwidth for a 3 dB axial ratio criterion is ~6%, with a nearly resistive input impedance of 75 Ω. An array antenna of the 36 curls shows a gain of 23 dB with an aperture efficiency of 73% 相似文献
87.
Hideki Hyuga Mark I. Jones Kiyoshi Hirao Yukihiko Yamauchi 《Journal of the American Ceramic Society》2004,87(5):894-899
Si3 N4 /carbon fiber composites have been produced with and without seeding by an extrusion and sintering process. In both cases the carbon fibers were aligned along the direction of extrusion, but the Si3 N4 grains were only aligned in the seeded material. The mechanical properties of the specimens showed anisotropy with respect to the grain alignment, with both strength and toughness being highest in the direction parallel to the extruding direction. In this direction the seeded specimen, where both the Si3 N4 grains and the carbon fibers were aligned, showed both higher fracture toughness and higher fracture strength than the nonseeded specimen where only the fibers were aligned. 相似文献
88.
A laser Doppler perfusion imager (LDPI) for evaluation of skin blood flow is presented and its use illustrated in two cases with a presumptive diagnosis of reflex sympathetic dystrophy (RSD) treated with local anesthetic sympathetic blocks. Among the advantages are the good spatial resolution over the area measured (12 x 12 cm) and that measurements can be done without contact with the skin. Generating a complete image takes 4.5 min but if higher temporal resolution is needed continuous measurements at one point are possible by use of another software routine. 相似文献
89.
A combined retrospective and prospective study of 129 beta-thalassaemia major patients seen between 1965 and 1995 in Sabah Hospital, Kuwait has been carried out. The age range at diagnosis was 2 to 84 months, median 9 months. In approximately 80 per cent, the patients were outcomes of first- or second-cousin marriages. Nine (7 per cent) of the patients were HBsAg positive, while 42 (33 per cent) were hepatitis C seropositive. Eleven (9 per cent) patients had had bone marrow transplantation (BMT). There was no BMT-related mortality, but there were three graft rejections and two cases of chronic graft-versus-host disease (GVHD). 相似文献
90.
Tatsuo Yamauchi 《应用聚合物科学杂志》2006,100(4):2895-2900
The local heat generation that accompanied tensile drawing of polymer films was successfully observed by infrared thermography as a series of temperature distribution images. These images showed that the high temperature part where rearrangements of molecular orientation and microcrystallines occurred was located mainly at the end of the necked part for the polymers that exhibited necking or appeared uniformly throughout films for the polymers that did not exhibit necking. The generated heat could be roughly estimated, and the relation between the estimated heat and mechanical work led to the thermodynamic investigation. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 2895–2900, 2006 相似文献