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Visualization of High-Speed Impact of Penetrator into Icy Target 被引量:1
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作者 kojiro suzuki Kazuya Namba Yasumasa Watanabe 《Journal of Flow Control, Measurement & Visualization》 2016年第2期56-69,共14页
For application to exploration under the surface of icy objects in the solar system, the penetration of an impact probe into an icy target was experimentally simulated by using the ballistic range. Slender projectiles... For application to exploration under the surface of icy objects in the solar system, the penetration of an impact probe into an icy target was experimentally simulated by using the ballistic range. Slender projectiles with a cylindrical body and various nose shapes were tested at the impact velocity 130 - 420 m/s. The motion of the penetrator, fragmentation of ice and crater forming were observed by the high-speed camera. It revealed that the crown-shaped ejection was made for a short time after the impact and then the outward normal jet-like stream of ice pieces continued for much longer time. The concave shape of the crater was successfully visualized by pouring the plaster into it. The two-stage structure, the pit and the spall, was clearly confirmed. The rim was not formed around the crater. Observation of the crater surface and the ice around the trace of the penetrator shows that both crushing into smaller ice pieces and recompression into ice blocks are caused by the forward motion of the penetrator. In case of a body with a flow-through duct, ice pieces entering the inlet at the nose tip were ejected from the tail, resulting in relaxation of the impact force. The correlation of the penetration distance and the crater diameter with the impact velocity was investigated. 展开更多
关键词 PENETRATOR ICE IMPACT Crater Forming Ballistic Range High-Speed Camera
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Visualization of High-Speed Impact of Projectile in Granular Sheet with Destructive Collision of Particles 被引量:1
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作者 Chihiro Masaki kojiro suzuki Yasumasa Watanabe 《Journal of Flow Control, Measurement & Visualization》 2018年第3期136-151,共16页
The impact and penetration of a projectile in a particle-laden space, which are expected to have frequently occurred during the formation of the solar system and will occur in the case of an impact probe for future pl... The impact and penetration of a projectile in a particle-laden space, which are expected to have frequently occurred during the formation of the solar system and will occur in the case of an impact probe for future planetary exploration, were experimentally simulated by using the ballistic range. A two-dimensional sheet made from small glass beads or emery powder was formed by the free-falling device through a long slit in the test chamber evacuated down to about 35 Pa. A polycarbonate projectile of a hemi-sphere-cylinder or sphere shape with the mass and diameter about 4 g and 25 mm, respectively, was launched at the velocity up to 430 m/s, and the phenomena were observed by the high-speed camera at 20,000 fps. From a series of images, the bow-shock-wave-like laterally facing U-shaped pattern over the projectile and the absence of particles in the trail behind it were clearly seen. At the impact of the particles on the projectile surface, fine grains were formed due to the destructive collision and injected outward from the projectile. The images obtained by different lighting methods including the laser light sheet were compared. The effects of the particle diameter, its material and the impact velocity were also investigated. 展开更多
关键词 BALLISTIC Range IMPACT GRANULAR Flow COLLISION HIGH-SPEED Camera
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Influence of Temperature, Moisture, and Light Conditions on the Germination of Seeds of <i>Erythronium japonicum</i>Decne
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作者 Yumiko Kanazawa Junko Abe +2 位作者 Shinji Kobayashi Kazue Shibuya kojiro suzuki 《Open Journal of Forestry》 2018年第1期105-116,共12页
Erythronium japonicum is a representative species of spring ephemeral, forest floor plants in substitution forests in Japan. Seed germination tests were conducted to observe the effects of temperature, light, and mois... Erythronium japonicum is a representative species of spring ephemeral, forest floor plants in substitution forests in Japan. Seed germination tests were conducted to observe the effects of temperature, light, and moisture content on the germination of E. japonicum. E. japonicum seeds did not germinate at constant temperatures of 5&#176C, 10&#176C, 15&#176C, 20&#176C, or 25&#176C. Seeds germinated at 5&#176C and 10&#176C after storage at 20&#176C for 1 or 2 months. Seed germinability was affected by desiccation to only 40% moisture content. Seeds germinated well in both light and dark conditions. Conditions under the leaf litter layer showed unique characteristics of temperature, light, and moisture content. The temperature was around 20&#176C under the leaf litter layer, even though it was 30&#176C above. The moisture content under the leaf litter layer was higher than that above. The leaf litter blocked out the sunlight. The temperature of 20&#176C necessary for E. japonicum germination occurred below, but not above, the leaf litter layer. The avoidance of decreasing in germinability from reduced seed moisture content in a short time is consistent with the high moisture conditions under the leaf litter layer. The leaf litter layer plays an important role in providing optimal conditions of temperature, light, and moisture content for the germination of E. japonicum seeds. 展开更多
关键词 Erythronium JAPONICUM Leaf LITTER Layer Life History Seed GERMINATION Spring EPHEMERAL
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胆道肿瘤临床实践指南(英文第三版) 被引量:9
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作者 Masato Nagino Satoshi Hirano +30 位作者 Hideyuki Yoshitomi Taku Aoki Katsuhiko Uesaka Michiaki Unno Tomoki Ebata Masaru Konishi Keiji Sano Kazuaki Shimada Hiroaki Shimizu Ryota Higuchi Toshifumi Wakai Hiroyuki Isayama Takuji Okusaka Toshio Tsuyuguchi Yoshiki Hirooka Junji Furuse Hiroyuki Maguchi kojiro suzuki Hideya Yamazaki Hiroshi Kijima Akio Yanagisawa Masahiro Yoshida Yukihiro Yokoyama Takashi Mizuno Itaru Endo 杨翼飞(译) 仇毓东(译) 赵梦珂(译) 伏旭(译) 蔡正华(译) 毛凉(审校) 《中华消化外科杂志》 CAS CSCD 北大核心 2021年第4期359-375,共17页
日本肝胆胰外科学会(JSHBPS)于2007年出版第一版胆道肿瘤(胆管癌、胆囊癌及壶腹癌)临床实践指南,于2014年更新第二版,2021年英文第三版胆道肿瘤临床实践指南围绕6个主题提出若干临床问题,基于相关循证医学证据并组织专家讨论后,最终确... 日本肝胆胰外科学会(JSHBPS)于2007年出版第一版胆道肿瘤(胆管癌、胆囊癌及壶腹癌)临床实践指南,于2014年更新第二版,2021年英文第三版胆道肿瘤临床实践指南围绕6个主题提出若干临床问题,基于相关循证医学证据并组织专家讨论后,最终确定推荐意见、推荐强度以及推荐说明。根据证据推荐分级的评估、制订与评价(GRADE)系统,推荐强度被分为1级(强)或者2级(弱)。英文第三版胆道肿瘤临床实践指南中提出的31个临床问题涵盖:(1)预防性治疗;(2)诊断;(3)胆道引流;(4)外科治疗;(5)化疗;(6)放疗。31个临床问题中,14个问题给予推荐强度为强的推荐意见,14个问题给予推荐强度为弱的推荐意见,剩余的3个问题未给予推荐意见。每条推荐意见都进行推荐强度说明。最新版指南基于循证医学证据,为临床提供了重要建议。未来与癌症登记数据库协作将是评估指南和建立新证据的关键。 展开更多
关键词 胆道肿瘤 临床实践指南 预防性治疗 循证医学证据 肝胆胰外科 胆道引流 推荐意见 壶腹癌
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