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71.
Shigeru Tanaka Kazuyuki Hokamoto Seiichi Irie Toshihiko Okano Zoran Ren Matej Vesenjak Shigeru Itoh 《Measurement》2011,44(10):2185-2189
Porous materials such as aluminum foam have been investigated for possible use as impact shock absorbers in transportation aeronautic applications. However, the response of aluminum foam during impacts at high velocities of more than 100 m/s is not yet fully understood. A high-velocity impact experiment was therefore carried out to clarify impact shock absorption properties of aluminum foam. A one-stage powder gun was used to accelerate an aluminum foam sample to impact a rigid wall. Velocity and deformation of the aluminum foam sample during impact was studied using a digital high-speed video camera, while the pressure wave in the aluminum foam sample was measured using a PVDF gauge. The experimental observations revealed uneven collapse of the aluminum foam sample structure during high speed impact with a general stress plateau effect, typical for cellular material structures when subjected to quasi-static loading. 相似文献
72.
Yoichi Kumada Daisuke Kuroki Hidefumi Yasui Takuhito Ohse Michimasa Kishimoto 《Journal of Bioscience and Bioengineering》2010,109(6):583-587
In this study, we characterized polystyrene-binding peptides (PS-tags) that possess a specific binding affinity for hydrophilic polystyrene (phi-PS) plates. Both the FITC-labeled PS19-1 (RAFIASRRIKRP) and PS19-6 (RIIIRRIRR) peptides showed strong binding affinity for commercially available hydrophilic, but not hydrophobic, PS plates in the presence of the non-ionic surfactant Tween 20. The dissociation constants (Kd) of the PS19-1 and PS19-6 peptides for the hydrophilic PS-A plate were 169 and 86 nM, respectively, and the Kd of both peptides increased with the concentration of NaCl or urea. Based on adsorption yield and residual activity of glutathione S-transferase (GST) after fusion with the PS19-6 peptide or its variants, it was found that the basic amino acid in the PS-tags, i.e., Arg was essential for the strong binding affinity of PS-tags in both the peptide and peptide-fused protein forms The aliphatic amino acids in PS19-6 and PS19-6L, such as Ile or Leu, were also effective. Thus, a series of PS-tags that possess this unusual feature, especially the peptides PS19-6 (RIIIRRIRR) and PS19-6L (RLLLRRLRR), are potential candidate affinity peptide tags for site-specific immobilization of proteins onto hydrophilic PS plates, which show potential as solid supports for protein-based biochips. 相似文献
73.
Kazuyuki Kakegawa Tsuyoshi Wakapayashi Yoshinori Sasaki 《Journal of the American Ceramic Society》1986,69(4):82-C-
A solution containing Mg2+ and Ta5+ was added to an aqueous ammonia solution of oxine, resulting in a precipitate. After the precipitate was thermally decomposed and fired, it was mixed with BaCO3 powder and fired again at high temperatures to obtain Ba(Mg1/3 Ta2/3 )O3 (BMT). This method resulted in BMT formation at temperatures lower than those used in the conventional mixed-oxide method, and single-phase BMT formed directly at 1300°C without intermediates. 相似文献
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iopeNet及其目的 总被引:1,自引:0,他引:1
我们已经提出的新的开放式区域控制网络“iopeNet”是一个全新的概念,与现有的设备控制网络没有冲突。本资料就此加以阐释。 相似文献
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77.
Yusuke Takeuchi Fangming Jin Kazuyuki Tohji Heiji Enomoto 《Journal of Materials Science》2008,43(7):2472-2475
Acidic hydrothermal degradation of glucose was examined in the presence of HCl, H2SO4, and H3PO4 with pH varying from 1.5 to 2.5 and reaction time varying from 1 to 10 min at 523 K, to investigate the effect of different
acid catalysts and acid concentration on the production of 5-hydroxymethyl-2-furaldehyde (HMF) and levulinic acid from glucose.
At lower acidities of pH 2.5, a considerably higher amount of HMF was produced. The increase in acid concentration accelerated
the conversion of HMF to levulinic acid. The order for the production of HMF using the three acids is in the sequence of H3PO4 > H2SO4 > HCl. On the contrary, the order for production of levulinic acid follows HCl > H2SO4 > H3PO4. In the experimental conditions used in this study, the highest yield of levulinic acid is about 55%, which was obtained
at pH 1.5 for 5 min in the case of HCl as an acid catalyst, and the total highest yields of HMF and levulinic acid are about
50%, which occurred at pH 2.0 for 5 min in the case of H3PO4 as an acid catalyst. 相似文献
78.
Y Ninomiya T Kishimoto T Yamazawa H Ikeda Y Miyashita H Kasai 《Canadian Metallurgical Quarterly》1997,16(5):929-934
Age is the most important factor for the durability of biological valves. With an original design the Carpentier-Edwards pericardial valve showed improved results at 10 years. The influence of age on valve related complications is studied with a 10 year follow up on 807 valvular replacements. METHODS: Between January 1984 and December 1993, 807 patients underwent valve replacements with a Carpentier-Edwards pericardial bioprosthesis. Patients, 193 were younger than 60 years, 284 between 60 and 70 years and 330 patients were older than 70 years. All patients but seven were followed up for an average of 4.18 years after their operation and total follow up was 3373 patient years. Patients were divided into three groups of age: group I, less than 60 years; group II, 60-70 years; group III, over 70 years. A retrospective comparison was made between age groups. RESULTS: At 11 years, valve related complications included 97 patients with 27 valve related deaths. Rates of valve related death increase with age linearized rate were 0.3, 0.6 and 1.2%, respectively. No difference was observed for rates of all valve related morbidity: 2.6, 2.4 and 3.5%, respectively. Risk of thromboembolism increased with age, linearized rates were: 0.3, 0.7 and 1.3%. Risk of deterioration and reoperation decreased with age, rates of deterioration were 0.8, 0.1 and 0%. Other valve related events had the same incidence in all groups. No statistical difference was observed between group II and group III for deteriorations and reoperations. CONCLUSIONS: The performance of the Carpentier-Edwards pericardial valve is the same at 10 years in group II and III. This study supports the clinical use of this tissue valve in patients over 60 years. The results in group I are satisfactory, nevertheless, a more durable biological valve is needed for young patients. 相似文献
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