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排序方式: 共有5189条查询结果,搜索用时 15 毫秒
971.
Takahashi T. Sekiguchi T. Takemura R. Narui S. Fujisawa H. Miyatake S. Morino M. Arai K. Yamada S. Shukuri S. Nakamura M. Tadaki Y. Kajigaya K. Kimura K. Itoh K. 《Solid-State Circuits, IEEE Journal of》2001,36(11):1721-1727
A multigigabit DRAM technology was developed that features a low-noise 6F2 open-bitline cell with fully utilized edge arrays, distributed overdriven sensing for operation below 1 V, and a highly reliable post-packaging repair scheme using a stacked-flash fuse. This technology, which can be used to fabricate a 0,13-μm 180-mm2 1-Gb DRAM assembled in a 400-mil package, was verified using a 57.6-mm2, 200-MHz array-cycle, 256-Mb test chip with 0.109-μm2 cells 相似文献
972.
Tadayoshi Yamada 《产业用纺织品》2001,19(11):6-8
介绍了日本非织造布工业的现状 ,内容包括产量、生产工艺、应用领域和原材料的使用等。根据全球经济动态及日本在亚洲的商业地位制定了日本非织造布的发展目标 相似文献
973.
Hideo Akimoto Toshiaki Kanazawa Masanobu Yamada Satoshi Matsuda Gabriel O. Shonaike Atsushi Murakami 《应用聚合物科学杂志》2001,81(7):1712-1720
We carried out tensile impact test and very low speed tensile test on ethylene‐based Ionomers (E/15wt %MAA) to clarify the relation between impact toughness and high‐ordered structure. We also studied the changes in high‐ordered structure under deformation by observing Differential Scanning Calorimetory (DSC) and Small‐Angle X‐ray Scattering (SAXS) of fractured surface. Na Ionomers showed ductile fracture in both high speed tensile impact (3 m/s) and very low speed tensile (2 mm/min). The disappearance of secondary melting point (Ti) in Na Ionomers was due to the destruction of ordered structure surrounding the ionic aggregate. Similar behavior was observed in 60% (or less) neutralized Zn Ionomers. However, 80% neutralized Zn Ionomer showed brittle failure in high‐speed tensile impact, and Ti did not disappear. SAXS studies of Na and Zn Ionomers after fracture, show no change both after molding (no aging) and after aging. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 1712–1720, 2001 相似文献
974.
Blend films of poly(L ‐lactide) (PLLA) and poly(vinyl alcohol) (PVA) were obtained by evaporation of hexafluoroisopropanol solutions of both components. The component interaction, crystallization behavior, and miscibility of these blends were studied by solid‐state NMR and other conventional methods, such as Fourier transform infrared (FTIR) spectra, differential scanning calorimetry (DSC), and wide‐angle X‐ray diffraction (WAXD). The existence of two series of isolated and constant glass‐transition temperatures (Tg's) independent of the blend composition indicates that PLLA and PVA are immiscible in the amorphous region. However, the DSC data still demonstrates that some degree of compatibility related to blend composition exists in both PLLA/atactic‐PVA (a‐PVA) and PLLA/syndiotactic‐PVA (s‐PVA) blend systems. Furthermore, the formation of interpolymer hydrogen bonding in the amorphous region, which is regarded as the driving force leading to some degree of component compatibility in these immiscible systems, is confirmed by FTIR and further analyzed by 13C solid‐state NMR analyses, especially for the blends with low PLLA contents. Although the crystallization kinetics of one component (especially PVA) were affected by another component, WAXD measurement shows that these blends still possess two isolated crystalline PLLA and PVA phases other than the so‐called cocrystalline phase. 13C solid‐state NMR analysis excludes the interpolymer hydrogen bonding in the crystalline region. The mechanical properties (tensile strength and elongation at break) of blend films are consistent with the immiscible but somewhat compatible nature of these blends. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 762–772, 2001 相似文献
975.
Vapor-phase catalytic dehydration of 1,2-propanediol was investigated over several catalysts, such as acidic oxides and supported heteropoly acids. These acids catalyze the dehydration of 1,2-propanediol to produce propanal. In particular, silica-supported silicotungstic acid showed the highest catalytic activity in the formation of propanal. At low conversions, however, propanal reacted with another 1,2-propanediol to produce a cyclic acetal (2-ethyl-4-methyl-1,3-dioxolane). Such acetal formation reduced the selectivity to propanal. Under optimum reaction conditions, 100% conversion was attained with propanal selectivity higher than 93 mol% at 200 °C. 相似文献
976.
In Mongolia many households use iodized salt only occasionally. We investigated whether the occasional use of iodized salt had an impact on the reduction of goiter size. We examined 685 children (8-11 years old) in five groups of households that (1) used iodized salt regularly, (2) used more than 10 kg of iodized salt annually, (3) used 6 to 10 kg annually, (4) used less than 6 kg annually, (5) and regularly used noniodized salt. The prevalence of goiter as determined by ultrasound in these five groups was 31.1%, 30.3%, 40.6%, 52.1%, 56.6%, respectively. There was no difference between goiter rates among the first three groups, but these groups had significantly lower rates than the last two groups. We concluded that annual use of more than 6 kg of iodized salt, preferably more than 10 kg, by a household had a beneficial effect on the rate of goiter. In addition, the possibility was suggested that households that consumed only iodized salt consumed less salt than other households. 相似文献
977.
978.
Masahiro Nawa Kiyotaka Yamada Naoki Kurizoe 《Journal of the European Ceramic Society》2013,33(3):521-529
The t–m transformation zone and related residual stress fields around two types of crack used for toughness measurements, i.e. SEVNB (arrested crack induced by a V-notch) and IF methods (indentation crack induced by a Vickers impression), are reported for a Ce-TZP/Al2O3 nanocomposite, in comparison with 3Y-TZP. The fact that Ce-TZP/Al2O3 exhibits significant high toughness value on occasions when evaluated by the IF method was determined to be clearly linked to the presence of wide ranged three-dimensional transformation configuration and resulting substantial compressive residual stress fields. In contrast, for 3Y-TZP, transformation behaviors around the two types of crack were quite similar, which proves that 3Y-TZP shows near toughness values for both SEVNB and IF methods. 相似文献
979.
Theoretical and experimental studies of the diffusional deposition of aerosols on model niters of intermediate packing density are reported. At low Reynolds number (Re« 1) and intermediate porosity (0.01 < α < 0.4), the Kuwabara flow field is applicable for parallel staggered model filters, and the diffusional deposition efficiency can be expressed as A = 2.92 n [(l-a)/k]1/3 Pe ?2/3. By applying a correction factor based on the ratio of pressure drops to this equation, the deposition efficiency for a fan model filter is n = A Pe ?2/3, where A has a value of 2.4–2.6 for α = 0.05–0.4. The efficiency increases with the fiber solidity, α for the parallel staggered filter, but is essentially independent of a for the fan model filter. Experimental results of diffusional deposition of ultrafine aerosols on wire screens which is used as a fan model filter has been performed. Summary data on screens and the fan model filter reported in the literature show that the single fiber efficiency is independent of the solid volume fraction and can be expressed as n = 2.7 Pe ?2/3 where Pe is the Peclet number (over the range of 0.02 < a < 0.35). The small difference between the experimental data and theory can be explained by the approximate nature of the flow field used in the theory. 相似文献
980.