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81.
Preloading clayey deposit by vacuum pressure with cap-drain: Analyses versus performance 总被引:4,自引:0,他引:4
A method of improving soft clayey deposit by combining cap-drain (CPVD) with vacuum pressure is described. The method uses a surface or subsurface soil layer as a sealing layer with no need to place an air-tightening sheet on the ground surface. It is explained that the method has advantages for the following situations: (a) a higher air/water permeability layer at ground surface and (b) combining vacuum pressure with embankment load. A case history of consolidating a reclaimed clayey deposit by combining CPVD with vacuum pressure is analyzed and discussed. The site was in an under-consolidated state before starting the project. It is shown that the method is effective, and the method proposed by Chai et al. [Ground deformation induced by vacuum consolidation. Journal of Geotechnical and Geoenvironmental Engineering, ASCE 131(12), 1552–1561] for calculating the vacuum-pressure-induced ground deformation is useful for the design of the vacuum consolidation project. The back-calculation shows that for this under-consolidated deposit, vacuum pressure caused plane strain type isotropic deformation near the ground surface. 相似文献
82.
Kuwatsuka H. Mikawa T. Miura S. Yasuoka N. Tanahashi T. Wada O. 《Photonics Technology Letters, IEEE》1990,2(1):54-55
An AlxGa1-xSb avalanche photodiode (APD) with an Al composition of 0.05 has been fabricated and tested. The measured gain-bandwidth (GB) product of the highly doped diode is 90 GHz. Such a large GB product has never been previously achieved by any APD materials sensitive in the long-wavelength region. This suggests the advantage of the AlxGa1-xSb material system for very high-speed operation 相似文献
83.
Suzuki E. Miura K. Hayasi Y. Tsay R.-P. Schroder D.K. 《Electron Devices, IEEE Transactions on》1989,36(6):1145-1149
The carrier transport properties in metal-oxide (top oxide) nitride-oxide (tunnel oxide) silicon (MONOS) memory structures have been investigated in steady-state conditions under negative gate bias voltage. Carriers were separated into holes and electrons utilizing an induced junction of the p-channel MONOS transistors. Two-carrier transport is confirmed in the structure at negative gate polarity. It is found that the relatively thick top oxide acts as a potential barrier to the holes injected from the Si into the thin nitride. It is also found that a portion of the electrons injected from the gate at negative gate polarity recombine with the holes injected from the Si even in such a thin nitride and/or at the top-oxide/nitride interface 相似文献
84.
1,3-Dipalmitoyl-2-oleoyl-sn-glycerol (POP) and 1,2-dioleoyl-3-palmitoyl-rac-glycerol (OOP) are two major molecular species that account for roughly half of the total triacylglycerols in palm oil. The
binary phase behavior of a POP/OOP mixture plays an important role in the crystallization of palm oil. We conducted thermodynamic
and kinetic studies of OOP and its mixtures with POP using differential scanning calorimetry and X-ray diffraction with a
conventional generator and synchrotron radiation. We found that OOP has two polymorphs, α as a metastable form and β′ as the
most stable form, and that the two forms are stacked in a triple-chain-length structure. The POP/OOP mixtures exhibited immiscible
eutectic natures in both their metastable and their most stable states, in contrast to POP/1,2-dipalmitoyl-3-oleoyl-rac-glycerol and POP/1,3-dioleoyl-2-palmitoyl-sn-glycerol mixtures, in which molecular compounds of a double-chain-length structure were formed. A time-resolved synchrotron
radiation X-ray diffraction study undertaken during the cooling and heating processes indicated that the α and β′ forms of
the POP and OOP fractions crystallized and melted in separate manners, and that crystallization of the β′ form and the polymorphic
transformation from α to β′ of POP and OOP are promoted in the presence of another component. The absence of molecular compound
crystals in the binary mixtures of POP/OOP is explained by taking into account the molecular interactions of acyl chain packing,
glycerol conformation, and methyl end stacking, among which glycerol conformation appeared to be most influential. 相似文献
85.
86.
Fotini-Niovi Pavlidou Marina Ruggieri Mario Gerla Ryu Miura 《Wireless Personal Communications》2004,28(2):161-162
Wireless Personal Communications - 相似文献
87.
Y. Nagasawa Y. Tachikawa E. Yamaguchi N. Tada T. Miura A. Itoh 《Advanced Synthesis \u0026amp; Catalysis》2016,358(2):178-182
A new catalytic method was developed for photo‐oxidizing the methyl group on aromatic heterocycles such as benzothiazole, benzoxazole, and quinoline to produce the corresponding aldehyde. This is the first report of the metal‐free catalytic synthesis of benzothiazole‐2‐carboxaldehydes using molecular oxygen as the terminal oxidant.
88.
Sobi Asako Takahisa Sakae Masahito Murai Kazuhiko Takai 《Advanced Synthesis \u0026amp; Catalysis》2016,358(24):3966-3970
Mild and simple catalytic systems consisting of molybdenum(VI) dichloride dioxide [MoO2Cl2] as a catalyst and a phosphine as reductant have been developed for the stereospecific deoxygenation of epoxides to alkenes. The reactions using 1,2‐bis(diphenylphosphino)ethane (dppe) and triphenylphosphine (PPh3) proceed with retention and inversion of stereochemistry, respectively. The mild reaction tolerates the presence of various functional groups and affords stereodefined substituted olefins in good yields.
89.
Migration of dehydroabietic and abietic acids from paper and paperboard food packaging into food-simulating solvents and Tenax TA 总被引:2,自引:0,他引:2
An investigation was undertaken to establish the concentration in paper products of dehydroabietic (DHA) and abietic (AA) resin acids, present in rosin, which are major toxicants of pulp- and paper-mill effluent. Their migration was studied from paper and paperboard products into various food-simulating solvents and the substitute fatty food simulant Tenax TA (modified polyphenylene oxide). DHA and AA were detected in five of 10 virgin paper products and in all 10 recycled paperboard products for food-contact use at concentrations of 14-500 and 110-1200 µg/g, respectively. In virgin paper products, the highest migration was into 95% ethanol or heptane, with negligible or no migration into other solvents. In recycled paperboard products, migration was highest into 95% ethanol, but was also observed into 20% ethanol, water and heptane. Migration to Tenax TA was also observed and the migration level increased with time. The maximum migration levels of DHA and AA into food simulants were 0.853 and 3.14 µg/g, respectively. The results suggest that, in the worst case, the daily intake of DHA and AA from paper and paperboard products was 50 times lower than the tolerable daily intake of rosin. 相似文献
90.
Kazuo Kato Osamu Miura 《IEEJ Transactions on Electrical and Electronic Engineering》2014,9(3):288-293
The spatial frequency contained in visual objects is known to affect human psychophysiology. In our previous study, we showed that event‐related potentials are affected by spatial frequency during a simple calculation task. In that study, however, we did not investigate the contribution of oscillatory neural activities. The purpose of the present study is to characterize the changes in oscillatory neural activity associated with cognitive processes, and to investigate how these signals are affected by the spatial frequency of a visual stimulus during simple calculation tasks. We investigate these issues by analyzing our previously collected electroencephalography (EEG) dataset using the same visual stimulus, tasks, subjects, and EEG recordings. In that study, four types of vertically striped visual stimuli were used. The visual stimuli contained embedded numbers (from 0 to 9) that possessed the following frequency (f) characteristics: white noise, 1/f, 1/f2, and 1/f3. The subjects were instructed to perform two tasks: ‘add numbers’ (addition task) and ‘do not add numbers’ (reference task). EEG data were recorded, and event‐related synchronization (ERS) and desynchronization (ERD) for each visual stimulus were analyzed on the basis of the intertrial variances of wavelet coefficients for theta, alpha, low‐beta, and gamma band activity. Eight healthy men (21–23 years) were recruited to participate in the study. Our results suggest the presence of a frequency discrimination function in the theta band activity in the fronto‐central area at the latency of 198 ms during the addition task. The alpha‐band ERD during completion of the reference task also showed a spatial frequency dependency. This phenomenon was observed in the left temporal‐parietal area at a latency of 376 ms, and is thought to be related to the perceptual filter. We conclude that the observed changes in oscillatory neural activity associated with cognitive processes are affected by spatial frequency. © 2014 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献