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排序方式: 共有662条查询结果,搜索用时 31 毫秒
51.
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
52.
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
53.
54.
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
55.
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
56.
57.
58.
Kenji Shiota Masaki Takaoka Shuji Yamaguchi Kazuyuki Oshita 《Drying Technology》2015,33(11):1286-1294
Because fine particulate matter ≤2.5 µm in diameter (PM2.5) causes health problems, PM2.5 emissions are of concern. However, little research on stationary sources has been conducted. To determine the concentration and filtration behavior of PM2.5, dust was collected from five fluid-bed sewage sludge incinerators (SSIs) sorted by particle size using cascade impactors. The average PM2.5 concentration was 0.00014–4.8 mg/Nm3. The total estimated amount of PM2.5 emissions from the SSIs for all plants in Japan was 0.96–8.9 tons/year. Since the SSIs with dry Electrostatic Precipitators (EP) contributed 75–99% of the total emissions, replacing dry EPs with bag filters would significantly reduce the PM2.5 emissions from SSI. 相似文献
59.
Yuichi Shimauchi Sachiko Ode Tsutomu Yamazaki Yuta Matsushima Kazuyuki Maeda 《Journal of Porous Materials》2010,17(3):305-312
A new vapor phase transport (VPT) technique to prepare an inverse silica replica of an ordered mesoporous carbon was developed.
Tetraethyl orthosilicate (TEOS) was infiltrated in mesoporous carbon CMK-3 as the hard template at 180 °C for 48 h under an
autogenous pressure in an autoclave in the presence of water. The samples obtained by removal of CMK-3 retained structural
regularity of CMK-3 with little shrinkage of framework, which were characterized by SAXRD, N2 adsorption, TG-DTA, and SEM. Influence of preparation temperature on the loading amount of silica was investigated. The multi-step
replication process was monitored by characterizing the replicated materials as well as intermediate composites. 相似文献
60.
Effects of rice straw returning methods on N<Subscript>2</Subscript>O emission during wheat-growing season 总被引:1,自引:0,他引:1
Erdeng Ma Guangbin Zhang Jing Ma Hua Xu Zucong Cai Kazuyuki Yagi 《Nutrient Cycling in Agroecosystems》2010,88(3):463-469
A field experiment was conducted in Jurong of Nanjing, Jiangsu Province, China from 2006 to 2008 to investigate N2O emission during the wheat-growing season as affected by various rice straw returning methods prior to wheat cultivation.
The study was designed to have four treatments: no rice straw applied (CK), rice straw burnt in situ (RB), rice straw evenly
incorporated into the topsoil (RI), rice straw evenly spread over the field as mulch (RM). Results showed that N2O emission was decreased by 24–29% in Treatment RB and by 3–18% in Treatment RI, but increased by 15–39% in Treatment RM,
compared with that in Treatment CK. The contents of soil total C and N at wheat harvest were significantly increased by 7–13%
and by 8–12% in Treatment RI, respectively, compared with that in Treatment CK. The wheat grain yield in Treatment RI was
1.0–1.2 times that in the Treatment CK. Based on these results, the best management practice of returning rice straw to the
soil prior to wheat cultivation is evenly incorporating rice straw into the topsoil, as the method tended to reduce N2O emission during the wheat-growing season and increase wheat yield and soil fertility. 相似文献