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951.
Tianzhun WuAuthor Vitae Yuji SuzukiAuthor Vitae 《Sensors and actuators. B, Chemical》2011,156(1):401-409
High-performance superlyophobic surfaces (SLSs) showing extremely low wettability for various liquids including water and oil are microfabricated following universal design criteria and formulated rules, and their wetting and hydrodynamic performances are systematically evaluated. Four design criteria are proposed to achieve reliable air-entrapped Cassie-Baxter (C-B) state for various liquids, especially low-surface-tension oils by considering the pressure balance and curvature requirement, as well as the pinning and suspending condition. By formulating the geometric design rules, a T-shaped configuration with a slight undercut is preferred as robust 3D structure for microfabricated high-performance of SLS. The static and dynamic contact angles (CAs) of water and hexadecane on SLS can be well tuned by varying the solid fraction. On the high-robustness and low-adhesion SLS, CAs up to 167° for hexadecane and 170° for water, and low contact angle hysteresis (CAH) ∼ 8° have been achieved. However, CAs on SLS cannot be well explained by three existing wetting models, which requires more efforts to exactly depict the droplet behavior on SLS. 相似文献
952.
采用聚碳酸酯毛细管作为红外空芯光纤的基管材料,制作了内直径为320微米的细径红外空芯光纤.内面镀有光滑银膜的聚碳酸酯毛细管,在近红外和中远红外波段获得了平坦的损耗-波长响应特性.用224根镀银聚碳酸酯空芯光纤,制作了长度40mm,截面积约50m2的红外图像光纤束.利用该红外光纤束成功进行了加热电阻丝的红外热图像传输实验.红外聚碳酸酯空芯光纤束具有柔韧性强、无毒等特点,在医疗及工业领域有广阔的应用前景. 相似文献
953.
Characterization of miRNAs in Milk Small Extracellular Vesicles from Enzootic Bovine Leukosis Cattle
Fumi Tsukada Shigeo Takashima Yoshiko Wakihara Yuji O. Kamatari Kaori Shimizu Ayaka Okada Yasuo Inoshima 《International journal of molecular sciences》2022,23(18)
Enzootic bovine leukosis (EBL) is a B-cell lymphosarcoma caused by the bovine leukemia virus (BLV). Most BLV-infected cattle show no clinical signs and only some develop EBL. The pathogenesis of EBL remains unclear and there are no methods for predicting EBL before its onset. Previously, it was reported that miRNA profiles in milk small extracellular vesicles (sEVs) were affected in cattle in the late stage of BLV infection. It raised a possibility that miRNA profile in milk sEVs from EBL cattle could be also affected. To characterize the difference in milk of EBL cattle and healthy cattle, we examined the miRNA profiles in milk sEVs from four EBL and BLV-uninfected cattle each using microarray analysis. Among the detected miRNAs, three miRNAs—bta-miR-1246, hsa-miR-1290, and hsa-miR-424-5p—which were detectable using quantitative real-time PCR (qPCR) and are associated with cancers in humans—were selected as biomarker candidates for EBL. To evaluate the utility of these miRNAs as biomarkers for EBL, their levels were measured using milk that was freshly collected from 13 EBL and seven BLV-uninfected cattle. bta-miR-1246 and hsa-miR-424-5p, but not hsa-miR-1290, were detected using qPCR and their levels in milk sEVs from EBL cattle were significantly higher than those in BLV-uninfected cattle. bta-miR-1246 and hsa-miR-424-5p in sEVs may promote metastasis by targeting tumor suppressor genes, resulting in increased amounts in milk sEVs in EBL cattle. These results suggest that bta-miR-1246 and hsa-miR-424-5p levels in milk sEVs could serve as biomarkers for EBL. 相似文献
954.
随着我国铁路线网密度的加大以及龙卷风等极端天气出现的频次增多,列车遭受龙卷风袭击的风险不断增加.利用物理模拟器对列车进行测压试验,通过试验得到的气动力对龙卷风作用下高速列车的运行安全性进行评估.结果 表明:受龙卷风气压降和水平风速的共同影响,列车距龙卷风中心不同相对位置时,所受风荷载作用机制明显不同;迎风侧轮轨横向力主... 相似文献
955.
Satoshi Ninomiya Chikage Imada Masafumi Nagai Yoshihiko Nakata Takaaki Aoki Jiro Matsuo Nobutsugu Imanishi 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2005,230(1-4):483-488
Total sputtering yields have been measured for SiO2 and Cu targets bombarded with Si ions at an incident energy between 500 keV and 5.0 MeV using a quartz crystal microbalance technique. In order to measure total yields accurately, we have developed a beam modulation technique to avoid the effect of thermal drift. In the MeV energy range, an ion penetrates through thin SiO2 and Cu targets and is implanted into a quartz crystal. Therefore, the thickness of these layers deposited on quartz crystals was carefully controlled to avoid damage of quartz crystal by incident ions. As a result, total sputtering yields of SiO2 increased with incident Si ion energy, while those of the Cu target decreased. The total yields of the SiO2 target were represented well by a power low of the electronic stopping power. 相似文献
956.
Yuichi Kusakabe Masaru Kanazawa Yuji Nojiri Masato Furuya Makato Yoshimura 《Journal of the Society for Information Display》2008,16(2):383-391
Abstract— An experimental projector that features double modulation to obtain high‐resolution (4096 × 2160 pixels) and high‐dynamic‐range images has been developed. Although a conventional projector contains three modulators for red, green, and blue and outputs light after combining the modulated light from these three sources, our projector has an additional modulator for luminance that modulates the combined RGB modulated light. It can display high‐resolution color images by combining three low‐resolution panels for chrominance modulation and one high‐resolution panel for luminance modulation. In addition, the dynamic range is dramatically improved because the double‐modulation scheme minimizes black levels in projected images. The projector demonstrates an extremely high dynamic range of 1.1 million to 1 and 10‐bit tone reproduction. 相似文献
957.
958.
InGaAs quantum dots formed in tetrahedral-shaped recesses on GaAs (111)B grown by metalorganic chemical vapor deposition 总被引:1,自引:0,他引:1
Yoshiki Sakuma Masashi Shima Yuji Awano Yoshiro Sugiyama Toshiro Futatsugi Naoki Yokoyama Kazuhito Uchida Noboru Miura Takashi Sekiguchi 《Journal of Electronic Materials》1999,28(5):466-480
Novel semiconductor quantum dots (QDs), grown in tetrahedral-shaped recesses (TSRs) formed on a (111)B GaAs substrate, are
described from both material science and device application points of view. After explaining the fabrication procedure for
TSRs, growth of InGaAs QDs and their optical properties are explained. It is revealed that an InGaAs QD of indium-rich chemical
composition is formed spontaneously at the bottom of each TSR. The mechanism of the QD formation is discussed in detail. It
is proved from magneto-photoluminescence that the QDs actually have optical properties peculiar to zero-dimensional confinement.
Several experimental results indicating excellent growth controllability of the QDs are presented. Finally, recent challenges
to apply the QDs to electronic memory devices are reported. Two kinds of devices, where the position of individual QD is artificially
controlled, are proposed for the first time and the preliminary experimental results are explained. 相似文献
959.
Modeling of inclusion removal in a tundish 总被引:6,自引:0,他引:6
Mathematical models have been developed to predict the removal of alumina inclusions from molten steel in a continuous casting
tundish, including the effects of turbulent collisions, reoxidation, flotation, and removal on the inclusion size distribution.
The trajectories of inclusion particles are tracked through the three-dimensional (3-D) flow distribution, which was calculated
with the K-ɛ turbulence model and includes thermal buoyancy forces based on the coupled temperature distribution. The predicted distributions
are most consistent with measurements if reoxidation is assumed to increase the number of small inclusions, collision agglomeration
is accounted for, and inclusion removal rates are based on particle trajectories tracked through a nonisothermal 3-D flow
pattern, including Stokes flotation based on a cluster density of 5000 kg/m3 and random motion due to turbulence. Steel samples should be taken from as deep as possible in the tundish near the outlet
and at several residence times after the ladle is opened, in order to best measure the Al2O3 concentration entering the submerged entry nozzle to the mold. Inclusion removal rates vary greatly with size and with the
presence of a protective slag cover to prevent reoxidation. The random motion of inclusions due to turbulence improves the
relatively slow flotation of small inclusions to the top surface flux layer. However, it also promotes collisions, which slow
down the relatively fast net removal rates of large inclusions. For the conditions modeled, the flow pattern reaches steady
state soon after a new ladle opens, but the temperature and inclusion distributions continue to evolve even after 1.3 residence
times. The removal of inclusions does not appear to depend on the tundish aspect ratio for the conditions and assumptions
modeled. It is hoped that this work will inspire future measurements and the development of more comprehensive models of inclusion
removal. These validated models should serve as powerful quantitative tools to predict and optimize inclusion removal during
molten steel processing, leading to higher quality steel. 相似文献
960.
板状碳酸钙和高纯氧化镁合成工艺的研究 总被引:1,自引:1,他引:0
论述了以白云石为原料合成板状碳酸钙和高纯氧化镁的方法,由单因素实验和多因素的正交实验,了各种因素对产品的影响,确定了适宜操作条件,产品的晶型、白度和纯度等质量标准,此工艺特点是用白石为资料同时生产板状碳酸钙和高纯氧化癣。 相似文献