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31.
以龙冈的在不规则荷载作用下土体应变的累积损伤理论为基础,提出了基于累积损伤理论的土石坝地震永久变形分析方法。采用大型静力和动力三轴仪,对某土石坝筑坝材料的静动变形特性进行了试验研究,确定了筑坝材料的静力和动力应力应变关系、累积应变模型和相应的材料参数。利用该方法,分别对在日本2008年6月14日岩手宫城内陆M7.2级地震作用下该土石坝的在建坝体和竣工后坝体的地震永久变形特性进行了研究。结果表明:在建坝体的坝内沉降计算值与现场实测值基本吻合,并且通过与其它土石坝实测值的比较,说明竣工后坝体的坝顶沉降预测值在合理范围之内。 相似文献
32.
Xiande Shen Yoshikazu Kitajyo Qian Duan Atsushi Narumi Harumi Kaga Noriaki Kaneko Toshifumi Satoh Toyoji Kakuchi 《Polymer Bulletin》2006,56(2-3):137-143
Summary The reaction of the carboxymethyl cellulose sodium salt (Na-CMC) (degrees of substitution (DS) = 1.2) with N-hydroxysuccinimide (Su-OH) in the presence of 1-hydroxybenzotriazole and 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC)
was carried out in water to obtain the Su-OH ester of carboxymethyl cellulose, Su-CMC, with the DS values of 0.19 – 1.04.
N-Allylcarbamoylmethyl cellulose (Allyl-CMC), which was prepared from the reaction of Su-CMC with an excess amount of allylamine,
was crosslinked by UV-irradiation. In addition, the photocrosslinked Allyl-CMC film was swollen with water to form a hydrogel
having a relatively high water-swelling property, e.g., the degree of swelling (ds) was ca. 360% for Allyl-CMC with the DS
of 0.93. 相似文献
33.
34.
Koji Matsumoto Kazuki Sakae Hirofumi Yamauchi Yoshikazu Teraoka 《International Journal of Refrigeration》2008,31(5):832-840
This study focused ice slurry formation in an ice storage system using W/O emulsions with 70 and 80% water contents. Emulsions consisted of a silicone oil–water mixture with a small amount of amino-group-modified silicone oil additive. Ice slurry was formed by cooling the emulsion without ice adhesion to the cooling wall, as water in the emulsion did not directly contact the cooling wall. As the structure of W/O emulsion slowed the propagation rate of supercooling dissolution, voltage and ultrasonic wave were applied to the W/O emulsion to propagate dissolution more quickly and decrease maximum supercooling degree, respectively. Thus, the effects of voltage and ultrasonic wave applications on propagation rate were clarified. 相似文献
35.
Takeshi Fujita Hideki Abe Toyokazu Tanabe Yoshikazu Ito Tomoharu Tokunaga Shigeo Arai Yuta Yamamoto Akihiko Hirata Mingwei Chen 《Advanced functional materials》2016,26(10):1609-1616
Precious metals (Pt and Pd) and rare earth elements (Ce in the form of CeO2) are typical materials for heterogeneous exhaust‐gas catalysts in automotive systems. However, their limited resources and high market‐driven prices are principal issues in realizing the path toward a more sustainable society. In this regard, herein, a nanoporous NiCuMnO catalyst, which is both abundant and durable, is synthesized by one‐step free dealloying. The catalyst thus developed exhibits catalytic activity and durability for NO reduction and CO oxidation. Microstructure characterization indicates a distinct structural feature: catalytically active Cu/CuO regions are tangled with a stable nanoporous NiMnO network after activation. The results obtained by in situ transmission electron microscopy during NO reduction clearly capture the unique reaction‐induced self‐transformation of the nanostructure. This finding can possibly pave the way for the design of new catalysts for the conversion of exhaust gas based on the element strategy. 相似文献
36.
Correlation between Chemical Dopants and Topological Defects in Catalytically Active Nanoporous Graphene 下载免费PDF全文
37.
Daichi Yazaki Tokuhisa Kawawaki Daisuke Hirayama Masanobu Kawachi Kosaku Kato Sota Oguchi Yuichi Yamaguchi Soichi Kikkawa Yoshiya Ueki Sakiat Hossain D. J. Osborn Fumihiko Ozaki Shunsuke Tanaka Jun Yoshinobu Gregory F. Metha Seiji Yamazoe Akihiko Kudo Akira Yamakata Yuichi Negishi 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(34):2208287
For the realization of a next-generation energy society, further improvement in the activity of water-splitting photocatalysts is essential. Platinum (Pt) is predicted to be the most effective cocatalyst for hydrogen evolution from water. However, when the number of active sites is increased by decreasing the particle size, the Pt cocatalyst is easily oxidized and thereby loses its activity. In this study, a method to load ultrafine, monodisperse, metallic Pt nanoclusters (NCs) on graphitic carbon nitride is developed, which is a promising visible-light-driven photocatalyst. In this photocatalyst, a part of the surface of the Pt NCs is protected by sulfur atoms, preventing oxidation. Consequently, the hydrogen-evolution activity per loading weight of Pt cocatalyst is significantly improved, 53 times, compared with that of a Pt-cocatalyst loaded photocatalyst by the conventional method. The developed method is also effective to enhance the overall water-splitting activity of other advanced photocatalysts such as SrTiO3 and BaLa4Ti4O15. 相似文献
38.
A new milling technique based on a focused ion beam (FIB) microsampling system is proposed to avoid the curtaining effect, commonly occurring in other FIB milling methods, in order to obtain a crosssectional device specimen with uniform thickness can be obtained for electron holographic observation. 相似文献
39.
The effects of heat treatment in Q2, O2 and N2, and Ar gases on the high temperature (500 C) electrical resistivity of indium tin oxide (ITO) film 52 nm thick prepared by chemical spray pyrolysis method were studied. The partial oxygen pressure effect on the resistivity was found to be
to
. The resistivity changes for cyclic exchange of O2 by Ar gas at 500 C. These lead to the conclusion that chemisorption of oxygen atoms in the film surface is dominant for this thin film, for thicker films such as 640 nm oxygen diffusion is found to occur. The Langmuir model of the monolayer isothermal adsorption of oxygen atoms in the surface is applicable to the rapid change of resistivity. 相似文献
40.
Suturin SM Sokolov NS Banshchikov AG Kyutt RN Sakata O Shimura T Harada J Tabuchi M Takeda Y 《Journal of nanoscience and nanotechnology》2011,11(4):2990-2996
Surface X-ray diffraction was applied to study structure of the fluorite-silicon interface forming upon epitaxial growth of CaF2 on Si(001) surface kept at 750 degrees C. Samples with CaF2 coverage of 1.5-4 (110)-monolayers were grown and in-situ characterized using synchrotron radiation. The 3 x 1-like surface reconstruction was observed in agreement with the previous studies by electron diffraction. Interestingly, a well pronounced splitting of the fractional x 1/3 reflections was revealed. This splitting was ascribed to the effect of antiphase domain boundaries in the row-like structure of the interface layer. The in-plane integrated intensities were used to reconstruct two-dimensional atomic structure of the high-temperature CaF2/Si(001) interface. 相似文献