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41.
Jet spreading width is one of the important characteristics of water jets discharging into the air. Many researchers have dealt with measuring this width, and contact measuring methods on the water jet surface were employed in a lot of the cases. In order to avoid undesirable effects caused by the contact on the jet surface, we introduce non-contact measuring methods with a laser instrument to the measurements of jet spreading width. In measurements, a transmitter emits sheet-like laser beam to a receiver. The water jet between the transmitter and the receiver interrupts the laser beam and makes a shadow. The minimum and maximum values of the shadow width are measured. In addition, pictures of the water jet are taken with a scale, and the shadow width is measured from the pictures. The experiments on various needle strokes were performed. Three kinds of width consistent with the jet structure were obtained. In the results, it can be concluded that our non-contact measuring methods are feasible. The data of jet spreading widths and jet taper were obtained and are useful for future applications. 相似文献
42.
Dr. Masanobu Nagano Takumi Oguro Ryo Sawada Dr. Toru Yoshitomi Prof. Keitaro Yoshimoto 《Chembiochem : a European journal of chemical biology》2021,22(23):3341-3347
Dysregulation of tumor necrosis factor-α (TNFα), a pro-inflammatory cytokine, causes several diseases, making it an important therapeutic target. Here, we identified a novel DNA aptamer against human TNFα using in vitro selection, which included a high exclusion pressure process against non-binding and weak binders through microbead-assisted capillary electrophoresis (MACE) in only three rounds. Among the 15 most enriched aptamers, Apt14 exhibited the highest inhibitory activity for the interaction between TNFα and its cognate receptor in mouse L929 cells. For further improving the bioactivity of the aptamer, dimerization programed by hybridization was evaluated, resulting in the Apt14 dimer exhibited a twofold higher binding affinity and stronger inhibition compared to the monomer counterpart. Rapid identification of bioactive aptamers using MACE in combination with facile dimerization by hybridization accelerates the discovery of novel bioactive aptamers, paving the way toward replacing current monoclonal antibody therapy with the less expensive and non-immunogenic aptamer therapy. 相似文献
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Koreyoshi Imamura Kohshi Kinugawa Ryo Kagotani Mayo Nomura Kazuhiro Nakanishi 《Journal of food engineering》2012
Amorphous matrices made up of sugar molecules, are frequently used in food and pharmaceutical industries. A drawback to their use is that they are susceptible to collapse, as a result of water uptake and an increase in temperature and subsequently crystallize. Herein, the crystallization characteristics of amorphous sugar (sucrose and α-lactose) preparations were analyzed, with the purpose of obtaining knowledge that could lead to the prediction of how long the amorphous state is retained under various conditions. The impact of compression, physical aging and freezing rate on the induction period (tind) for crystallization were examined. Freeze-dried sugar samples were compressed at 74 or 443 MPa (5 min) and then rehumidified at specified RHs. Some freeze-dried sucrose samples were physically aged, and alternatively freeze-drying was conducted under different conditions. The isothermal crystallization of the prepared samples at different temperatures (T), the glass transition and the crystallization temperature (Tcry) were measured, using differential scanning calorimetry. The compression markedly decreased the tind, while significantly lowered the hygroscopicity. Physical aging and slower-freezing also shortened the tind. The tind was found to be correlated exclusively with (Tcry–T), regardless of rehumidification, compression, sugar type, physical aging and freezing rate in the freeze-drying process. 相似文献
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Phase transformation and interface segregation behavior in Si3N4 ceramics sintered with La2O3–Lu2O3 mixed additive 下载免费PDF全文
Ryosuke Urakami Yukio Sato Masayoshi Ogushi Takeshi Nishiyama Aoi Goto Kazuhiro Yamada Ryo Teranishi Kenji Kaneko Mikito Kitayama 《Journal of the American Ceramic Society》2017,100(3):1231-1240
Microstructure and mechanical property of silicon nitride (Si3N4) ceramic are strongly dependent on the selection of sintering additives. When rare‐earth (RE) oxide is used as the sintering additive, segregation of RE ions at interface between Si3N4 grain and intergranular glassy film (IGF) is believed to play a critical role. Although the ionic radius of RE ion is known to be an empirical parameter to modify the mechanical property, the correlation between the segregated ions and their ionic radii is still under controversy. In order to address this issue, (i) rate of α‐β phase transformation and (ii) segregation behavior at the interface were studied for Si3N4 ceramics sintered using mixture of La2O3 and Lu2O3 as additives in this study. Specimens of Lu content 30% and higher exhibited lower activation energies for the α‐β phase transformation as compared with those of Lu content 20% and lower. In terms of the segregation behavior, La was preferably segregated at one site and Lu at the other site along β‐Si3N4/IGF interface in the specimens of Lu content 30% and higher. It is understood from these results that Lu segregation site should be more closely related with grain growth. 相似文献
46.
Although numerous swarm robotic systems have already been developed, they have exhibited limited adaptability. This was partly because the previous researchers designed the control schemes on the basis of informational interaction, without considering the physical effects of the environment. To tackle this problem, we employ an unconventional approach: we design a control scheme for swarm robots based on their physical interaction in a hydrodynamic field, inspired by biological swarming. Through simulations using a smoothed particle hydrodynamics method, we show that the proposed control scheme allows agents to form an ordered swarm in response to their environment. 相似文献
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Jae-Yeol Jeon Ryo Matsumoto Hiroshi Utsunomiya 《Journal of Materials Processing Technology》2014,214(11):2514-2521
Die quenching of AA2024 aluminum alloy billets was carried out on a servo press with ram-motion control of WC-20 mass%Co dies directly after solution heat treatment (SHT). To clarify the dependence on billet size for die quenching, two billets with a height of h0 = 8 mm or 16 mm and with the same diameter of 16 mm were prepared. The cylindrical billets were heated in an electric furnace at 823 K and transferred to the press. Then the billets were uniaxially compressed with a reduction in height (Δh/h0) of 2% or 5%, and further held between the dies. The sandwiching duration by dies (td.q.) was varied from 0 to 8 s. Based a measured temperature change, hardness and TG–DTA analysis, it is found that die quenching is successfully carried out without precipitation hardening only in the case of the billet with a height of 8 mm and td.q. > 6 s. The reduction in height is limited less than 5% by intergranular fracture on side surface of billet during the die quenching process. 相似文献
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Ryo Mitsugi Tomoo Itoh Ryoichi Fujiwara 《International journal of molecular sciences》2015,16(7):14997-15008
The human DNAJB3 gene encodes a DNAJ (Heat shock protein 40; Hsp40) homolog, subfamily B, member 3 chaperone protein (DNAJB3), which can be down-regulated in disease conditions, as observed in decreased expression of DNAJB3 mRNA in peripheral blood mononuclear cells (PBMC) of obese patients. Recently, humanized UDP-glucuronosyltransferase (UGT) 1 mice (hUGT1 mice) were developed, in which the introduced human UGT1 gene contained a gene encoding human DNAJB3. In the present study, we analyzed the expression of human DNAJB3 mRNA in hUGT1 mice. Among the examined tissues, the testis had the highest expression of human DNAJB3 mRNA, while the lowest expression was observed in the liver. We found that the pattern of tissue-specific expression of mouse Dnajb3 in hUGT1 mice was very similar to that of human DNAJB3. We further demonstrated that the expression of human DNAJB3 in the liver was significantly reduced in high-fat-diet-fed hUGT1 mice compared to the expression level in the control mice, indicating that the expression of human DNAJB3 in hUGT1 mice could be similarly regulated in disease conditions such as obesity. Humanized UGT1 mice might therefore be useful to investigate the physiological role of human DNAJB3 in vivo. 相似文献