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排序方式: 共有881条查询结果,搜索用时 15 毫秒
91.
The State of the Art of Sludge Drying in Japan 总被引:1,自引:0,他引:1
92.
93.
Measures preventing an earthquake-induced soil liquefaction are of significant importance to mitigate the liquefaction hazards. An air-injection technique may be a simple, inexpensive method - this leads the saturated soils to the desaturated by injecting pressurized air, resulting in a higher liquefaction strength and lower susceptibility. The objective of this study is to investigate the evolution of desaturation process during air injection into saturated soil deposits and verify the validity of a multiphase flow simulator if it is capable of being applied for predicting the process as well as the distribution of degree of saturation after the air injection ceased. In this study simplified model tests that simulate the air injection into saturated soils using air-injection probes, are conducted using two different sizes of soil containers. The experiments using the small container are aimed to examine the nominal rates and magnitudes of the soil desaturation driven by air injection, whilst those with the large container are performed to obtain not only the rates and magnitudes but also the distributions of the desaturated zones within the soil. The results obtained indicate, although clearly depending on the physical properties of targeted soils, that the evolution of desaturation is strongly controlled by the air pressures injected and the soil permeabilities. Numerical analyses are also conducted using a multiphase flow simulator to describe the evolution of the soil desaturation, and to examine the applicability of the model as a prediction tool enabling an evolution of desaturation in situ to be followed with time and space. Predictions show a relatively good agreement with the experimental measurements regarding the rates, magnitudes, and distribution of desaturation specifically for the small-container experiments although predictions of desaturated domain slightly overestimate the measurements for the large-container experiments. Thus, this study indicates that the numerical model described is applicable to field problems when the soil properties in terms of flow transport are well-constrained. 相似文献
94.
95.
Kawahara T. Horiguchi M. Etoh J. Sekiguchi T. Kimura K. Aoki M. 《Solid-State Circuits, IEEE Journal of》1995,30(9):1030-1034
A low-power dynamic termination scheme is proposed and demonstrated as a way to reduce power dissipation for high-speed data transport. In this scheme, the transmission lines are terminated only if the signals change. The gate of a switching MOS transistor connected to a termination resistor is driven by differentiating the transmission signal with a resistor and a capacitor. The power dissipation of the terminating resistor can be reduced to 1/5 in the conventional determination scheme, and overshoot can be reduced to 1/5 that in the open scheme. This scheme is promising for use with palm-top equipment, facilitating high-speed low power operation 相似文献
96.
Yoshinori Iwahashi Zenji Horita Minoru Nemoto Terence G. Langdon 《Metallurgical and Materials Transactions A》1998,29(10):2503-2510
Experiments were undertaken to compare the equal-channel angular (ECA) pressing of Al-1 pct Mg and Al-3 pct Mg solid-solution
alloys with pure Al. The results reveal both similarities and differences between these three materials. Bands of subgrains
are formed in all three materials in a single passage through the die, and these subgrains subsequently evolve, on further
pressings through the die, into an array of grains with high-angle boundaries. However, the addition of magnesium to an aluminum
matrix decreases the rate of recovery and this leads, with an increasing Mg content, both to an increase in the number of
pressings required to establish a homogeneous microstructure and to a decrease in the ultimate equiaxed equilibrium grain
size. It is concluded that alloys exhibiting low rates of recovery should be especially attractive candidate materials for
establishing ultrafine structures through grain refinement using the ECA pressing technique. 相似文献
97.
98.
The spanning tree model' (utilising Gaussian-flight statistics) for the kinetics of simultaneous ring-chain competition in linear and branched polycondensation reactions has been extended by the use of the path weighting method of cascade statistics to the system glycerol/adipic acid. In this system there is no single fixed increment in ring sizes as more units are added to the ring-closing path, since a glycerol unit incorporated through the reaction of its two primary hydroxyls contributes a longer increment to the path length than when one primary and one secondary hydroxyl are involved. A computational method has been developed to count, as the reaction proceeds, the mean number of paths of all lengths available for forming a cycle back to a given root functionality, with each path receiving the correct Gaussian weight according to its length. 相似文献
99.
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
100.
Sumithra K Wendakoon Yoshinori Ueda Yoshihiro Imahori Megumi Ishimaru 《Journal of the science of food and agriculture》2006,86(13):2241-2241
The original article to which this Erratum refers was published in Journal of the Science of Food and Agriculture, 2006; 86: 1475–1480. 相似文献