Koji Yamaguchi  Takayuki Abe  Kazuo Kobayashi  Etsuo Takeuchi  Hisashi Hirukawa  Yoshio Maeda 《Science and Technology of Advanced Materials》2013,14(7-8):545-551

Gigacycle fatigue data sheets have been published since 1997 by the National Institute for Materials Science. They cover several areas such as high-cycle-number fatigue for high-strength steels and titanium alloys, the fatigue of welded joints, and high-temperature fatigue for advanced ferritic heat-resistant steels. Some unique testing machines are used to run the tests up to an extremely high number of cycles such as 10¹⁰ cycles. A characteristic of gigacycle fatigue failure is that it is initiated inside smooth specimens; the fatigue strength decreases with increasing cycle number and the fatigue limit disappears, although ordinary fatigue failure initiates from the surface of a smooth specimen and a fatigue limit appears. For welded joints, fatigue failure initiates from the notch root of the weld, because a large amount of stress is concentrated at the weld toe. The fatigue strength of welded joints has been obtained for up to 10⁸ cycles, which is an extremely high number of cycles for large welded joints. The project of producing gigacycle fatigue data sheets is still continuing and will take a few more years to complete. r 2007 Published by Elsevier Ltd.  相似文献   

    

Yoshio Nosaka  Masami Matsushita  Junichi Nishino  Atsuko Nosaka 《Science and Technology of Advanced Materials》2013,14(2):143-148

In order to utilize visible light in photocatalytic reactions, nitrogen atoms were doped in commercially available photocatalytic TiO₂ powders by using an organic compound such as urea and guanidine. Analysis by X-ray photoelectron spectroscopy (XPS) indicated that N atoms were incorporated into two different sites of the bulk phase of TiO₂. A significant shift of the absorption edge to a lower energy and a higher absorption in the visible light region were observed. These N-doped TiO₂ powders exhibited photocatalytic activity for the decomposition of 2-propanol in aqueous solution under visible light irradiation. The photocatalytic activity increased with the decrease of doped N atoms in O site, while decreased with decrease of the other sites. Degradation of photocatalytic activity based on the release of nitrogen atoms was observed for the reaction in the aqueous suspension system.  相似文献   

    

Liang Li  Peicai Wu  Xiaosheng Fang  Tianyou Zhai  Lun Dai  Meiyong Liao  Yasuo Koide  Hongqiang Wang  Yoshio Bando  Dmitri Golberg 《Advanced materials (Deerfield Beach, Fla.)》2010,22(29):3161-3165

  相似文献   

    

Naoto Shirahata  Tsuyoshi Hasegawa  Yoshio Sakka  Tohru Tsuruoka 《Small (Weinheim an der Bergstrasse, Germany)》2010,6(8):915-921

  相似文献   

    

Shiliang Wang  Yuehui He  Xiaosheng Fang  Jin Zou  Yong Wang  Han Huang  Pedro M. F. J. Costa  Min Song  Baiyun Huang  Chain T. Liu  Peter K. Liaw  Yoshio Bando  Dmitri Golberg 《Advanced materials (Deerfield Beach, Fla.)》2009,21(23):2387-2392

  相似文献   

    

Xiaosheng Fang  Yoshio Bando  Meiyong Liao  Ujjal K. Gautam  Chunyi Zhi  Benjamin Dierre  Baodan Liu  Tianyou Zhai  Takashi Sekiguchi  Yasuo Koide  Dmitri Golberg 《Advanced materials (Deerfield Beach, Fla.)》2009,21(20)

  相似文献   

    

Wang MS  Golberg D  Bando Y 《Advanced materials (Deerfield Beach, Fla.)》2010,22(47):5350-5355

  相似文献   

    

Urata C  Yamauchi Y  Aoyama Y  Imasu J  Todoroki S  Sakka Y  Inoue S  Kuroda K 《Journal of nanoscience and nanotechnology》2008,8(6):3101-3105

A new type of hierarchically porous materials is fabricated by assembling mesoporous nanoparticles via spray drying. Well-dispersed mesostructured silica nanoparticles (MSN), whose particle size distribution was narrow in the range of 20 nm and 50 nm, were prepared by a thermal deposition method. By spray drying a MSN suspension, MSN were assembled into spherical secondary particles. After calcination, the spherical particles have two types of mesopores, mesopores of 3 nm in size inside of calcined MSN and larger inter-nanoparticle mesopores of about 15-20 nm. This hierarchical pore system should provide nanospaces for efficient mass transport of guest species with different sizes.  相似文献   

  总被引：1，自引：0，他引：1  

Atsushi KawamataHirozo Mihashi  Yoshio KanekoKazuki Kirikoshi 《Engineering Fracture Mechanics》2002,69(2):249-265

An experimental study was carried out to find material parameters for making fiber reinforced cementitious composites (FRCC) more ductile. One of the dominant factors to control the ductility might be hidden in fracture property of matrix as well as the interface property between fiber and matrix. Therefore this study varied air content and water-binder ratio as the parameters to change the fracture property of matrix and experimentally examined their influence on the ductility of FRCC by three-point bend test with notched beams. As a result, it is concluded that fracture toughness of the matrix could be one of key parameters to control the ductility of FRCC. In case of a polyethylene fiber used in this study, the optimum value of the fracture toughness (critical strain energy release rate): G_IC of the matrix was obtained to be 7.5-8.0 N/m.  相似文献   

    

Yasunari Nishikata  Masa-aki Kakimoto  Atsushi Morikawa  Yoshio Imai 《Thin solid films》1988,160(1-2):15-20

Multilayer films of poly(amide-imide)s were prepared as follows: (1) monolayers of long alkyl amine salts of poly(amide-amic acid) were prepared at the air- water interface; (2) these monolayers were deposited on an appropriate plate by the Langmuir-Blodgett method; (3) the multilayers of poly(amide-amic acid) salts on the solid support were treated with acetic anhydride to afford poly(amide-imide) multilayer films. The monolayer thickness of the poly(amide-imide) multilayer films were 0.43–0.55 nm.  相似文献