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排序方式: 共有1215条查询结果,搜索用时 15 毫秒
61.
Yuki Kotani Shigetaka Okano Shinji Kobayashi Tadahisa Tsuyama Masahito Mochizuki 《Welding International》2016,30(11):826-834
Reduction or control of angular distortion without additional processes is demanded because it takes a lot of time and effort to correct the angular distortion of fillet-welded T-joints. In this study, the reduction or control of angular distortion of both sides of a fillet-welded T-joint by welding with trailing reverse-side gas heating was investigated through a welding experiment and its numerical simulation. First, the effect of gas heating position and intensity on the reduction in angular distortion was experimentally investigated using a gas burner. The results showed that angular distortion became smallest when reverse-side heating using the gas burner was located 50 mm backward of the welding torch. Also, the concentrated gas flame with increased propane and oxygen gas flow was effective for reducing angular distortion. It was clarified that the angular distortion could be controlled completely with an appropriate reverse-side gas heating condition. Next, the numerical simulation model of welding and gas heating was constructed based on comparison with the measured temperature histories and angular distortion. Through the numerical simulation of welding with a trailing reverse-side gas, more detailed understanding of the effect of gas heating condition on reduction in angular distortion was developed. In addition, it was confirmed that the gas heating position for the smallest angular distortion is dependent on the temperature distribution along the thickness of the flange plate. 相似文献
62.
Toshiaki Ozawa Koji Endo Takashi Masui Masahiro Miyaki Keiko Matsuo Shinji Yamada 《Journal of surfactants and detergents》2016,19(4):785-794
Five anionic surfactants widely used in commercial skin cleansers were studied: sodium polyoxyethylene lauryl ether carboxylate (EC), sodium polyoxyethylene alkyl ether sulfate (ES), sodium dodecyl sulfate, potassium laurate, and N-cocoyl-l-glutamic acid monosodium salt. The amount of surfactant from aqueous solution adsorbed into the stratum corneum (SC), the degree of SC swelling, the change of the secondary structure of SC proteins (denaturation). The surface tension of surfactant–zein mixed solutions, and the solubilization behavior of zein were measured. Results showed that EC had the lowest adsorption into SC, the lowest SC swelling, and lowest denaturation of SC proteins. Low interactions between surfactants and SC proteins were also observed for EC/ES mixture solutions as well as. Mixing EC with ES good foaming performance. The EC/ES mixture, at about 1:1 ratio, is an excellent surfactant system for skin cleanser applications having cleansing characteristics and mildness to the skin. 相似文献
63.
Takashi Tsuchida Takeo Moriwaki Shinji Nakai A.M.R.G. Athapaththu 《Soils and Foundations》2019,59(4):1085-1102
This study was intended to examine the mechanism of multiple slope failures and debris flows that occurred in the outskirts of Hiroshima on 20th August 2014. A field survey of the mountain stream where large-scale damage was incurred was carried out and the characteristics of debris flows which made serious damages were investigated. There were five findings of this study. (1) The initiation of debris flows was not limited to thin and planar shallow failures, but also showed V or U shapes, where the eroded sediments seemed to be pushed out by artesian water, and the eroded depth exceeded several meters at many locations. (2) There were areas with high permeability, such as faults, fracture zones, and joints in Mt. Abusan. It is inferred that the constantly present groundwater in these areas became artesian water because of a large amount of rainfall in upstream locations. This quickly destabilized the slopes on a large scale. (3) There were at least three estimated debris flows at the mountain stream above Midorigaoka prefectural apartments in Yagi 3-Chome, where the worst damage occurred. The mountain stream near Abu-no-Sato housing complex also had multiple debris flows. Here, the secondary debris flow changed its flow path because of the presence of sediments from an earlier debris flow. (4) The actual volumes of flowed mass were much larger than that predicted at 11 of the 18 mountain streams in Midori-i and Yagi districts. The volume of the mass of five of these mountain streams was more than twice the estimated volume. It is necessary to modify the method of calculating the volume of unstable sediments in the mountain stream. (5) It was found that the devastating damage of buildings and human lives took place in the areas well beyond the special restricted zones. The present method to designate the special restricted zone must be revised considering such problems as the underestimation of the volume of unstable sediments, the assumptions of a single debris flow and on the direction of debris flow, and the effect of the difference on rock and soil types. 相似文献
64.
A series of hyper-branched polyimide (HBPI)/mesoporous SiO2 nanocomposite films were prepared from a fluorinated anhydride (6FDA), a fluorinated triamine (TFAPOB), and mesoporous SiO2 nanoparticles (NPs). The anhydride-terminated precursor of HBPI was functionalized using a coupling agent prior to mixing with SiO2 NPs. The morphologies and thermal-optical properties of the nanocomposite films were investigated, with particular focus on their optical transparency, refractive indices (n), and thermo-optical (TO) coefficients. The absolute values of TO coefficients (|dn/dT|) of HBPI film (50.8 ppm/K) were significantly reduced to 13.4 ppm/K by homogeneous dispersion of 15 wt% of SiO2 NPs. The HBPI/SiO2 composite films exhibited high thermal stability without significant weight loss of up to 400 °C in air. The films also exhibited small coefficients of linear thermal expansion (CTEs) within the range 30–40 ppm/K. In addition, enhanced interfacial interactions between SiO2 and HBPI significantly improve the optical transparency with cutoff wavelengths shorter than 450 nm. The refractive indices of HBPI/SiO2 composite films were found to range from 1.477 to 1.502, which agrees well with the calculated values. This study shows that the incorporation of SiO2 NPs in multi-functional HBPI matrix is a promising approach to prepare high performance thermally stable films for thermo-optic applications. 相似文献
65.
A novel vinyl ether-type RAFT agent, benzyl 2-(vinyloxy)ethyl carbonotrithioate (BVCT) was synthesized for various block copolymers via the combination of living cationic polymerization of vinyl ethers and reversible addition−fragmentation chain transfer (RAFT) polymerization. The novel BVCT–trifluoroacetic acid adduct play an important role to produce well-defined block copolymers, which is both as a cationogen under EtAlCl2 initiation system in the presence of ethyl acetate for living cationic polymerization and a RAFT agent for blocks by RAFT polymerization. The resulting polymer, poly(vinyl ether)s, by living cationic polymerization had a high number average α-end functionality (≥0.9) as determined by both 1H NMR and MALDI-TOF-MS spectrometry. In addition, this poly(vinyl ether)s worked well as a macromolecular chain transfer agent for RAFT polymerization. The RAFT polymerization of radically polymerizable monomers was conducted in toluene using 2,2′-azobis(isobutyronitrile) at 70 °C. For example, a double thermoresponsive block copolymer (MOVE61-b-NIPAM150) consisting of 2-methoxyethyl vinyl ether (MOVE) and N-isopropylacrylamide (NIPAM) was prepared via the combination of living cationic polymerization and RAFT polymerization. The block copolymer reversibly formed and deformed micellar assemblies above the phase separation temperature (Tps) of poly(NIPAM) block in water. This BVCT is not only functioned as an initiator, but also acted as a monomer. When BVCT was copolymerized with MOVE by living cationic polymerization, followed by graft copolymerization with NIPAM via RAFT polymerization, well-defined graft copolymers (MOVEn-co-BVCTm)-g-NIPAMx (n = 62–73, m = 1–9, x = 19–214) were successfully obtained. However, no micelle formed in water above Tps of poly(NIPAM) graft chain unlike the case of block copolymers. 相似文献
66.
Shinji Miwa Norio Yamamoto Katsuhiro Hayashi Akihiko Takeuchi Kentaro Igarashi Hiroyuki Tsuchiya 《International journal of molecular sciences》2022,23(3)
Simple SummaryChondrosarcomas develop chemoresistance to standard anticancer drugs, making it difficult to control unresectable or metastatic chondrosarcomas. To improve the clinical outcomes of chondrosarcoma, new treatment approaches, such as molecule-targeting agents and immunotherapy, are needed. Recent research has revealed promising biomarkers and therapeutic targets for chondrosarcoma. In addition, several molecule-targeting agents have shown favorable antitumor activities in several clinical studies in patients with advanced sarcomas, including chondrosarcoma. This review summarizes recent basic studies on biomarkers and therapeutic targets and recent clinical studies on treating chondrosarcomas.AbstractDue to resistance to standard anticancer agents, it is difficult to control the disease progression in patients with metastatic or unresectable chondrosarcoma. Novel therapeutic approaches, such as molecule-targeting drugs and immunotherapy, are required to improve clinical outcomes in patients with advanced chondrosarcoma. Recent studies have suggested several promising biomarkers and therapeutic targets for chondrosarcoma, including IDH1/2 and COL2A1. Several molecule-targeting agents and immunotherapies have shown favorable antitumor activity in clinical studies in patients with advanced chondrosarcomas. This review summarizes recent basic studies on biomarkers and molecular targets and recent clinical studies on the treatment of chondrosarcomas. 相似文献
67.
The alkyl derivatives of boehmite were prepared by solvothermal reaction of aluminum isopropoxide in n-alcohols (ethanol, 1-butanol, 1-hexanol, 1-octanol and 1-dodecanol) and the products were recovered as aerogel/xerogel by
the removal of the solvent at the end of reaction. Aerogel or xerogel can be obtained simply by using only a reaction vessel
(autoclave) and the obtained products were composed of plate-like particles having a well-developed boehmite structure. The
alumina powders obtained by calcination of these products had relatively large pore-volumes ranging from 1.35 to 2.56 cm3/g. Transformation into α-Al2O3 was retarded even after calcination at 1200 °C. The effect of n-alcohols used in the solvothermal reaction on the phase, morphology and pore-texture of the alumina samples are discussed. 相似文献
68.
Kazuaki Nakamura Reiko Mizutani Atsushi Sanbe Shin Enosawa Mureo Kasahara Atsuko Nakagawa Yoko Ejiri Norie Murayama Yuki Miyamoto Tomohiro Torii Shinji Kusakawa Junji Yamauchi Motohiro Fukuda Hiroshi Yamazaki Akito Tanoue 《Journal of Bioscience and Bioengineering》2011,111(1):78-84
A micro-space cell culture system was recently developed in which cells such as hepatocytes can be cultured and formed into a multicellular three-dimensional (3D) architecture. In this study, we assessed the performance of HepG2 cells cultured in this micro-space cell culture system in a drug toxicity test, and evaluated the effects of micro-space culture on their hepatocyte-specific functions. The micro-space cell culture facilitated the formation of 3D HepG2 cell architecture. HepG2 cells cultured in a micro-space culture plate exhibited increased albumin secretion and enhanced mRNA expression levels of cytochrome P450 (CYP) enzyme compared to those cultured in a monolayer culture. When the cells were exposed to acetaminophen, a hepatotoxic drug, the damage to the HepG2 cells grown in micro-space culture was greater than the damage to the HepG2 cells grown in monolayer culture. In addition, human primary hepatocytes grown in micro-space culture also exhibited increased albumin secretion, enhanced CYP mRNA expression levels and increased sensitivity to acetaminophen compared to those grown in monolayer culture. These results suggest that this micro-space culture method enhances the hepatocyte-specific functions of hepatocytes, including drug-metabolizing enzyme activities, making hepatocytes grown in the micro-space culture system a useful tool for evaluating drug toxicity in vitro. 相似文献
69.
Shinji Yamashita Susumu Kanno Ayako Honjo Yurika Otoki Kiyotaka Nakagawa Mikio Kinoshita Teruo Miyazawa 《Lipids》2016,51(2):199-210
Ethanolamine plasmalogen (PlsEtn), which is present at high levels in brains, is believed to be involved in neuronal protection. The present study was performed to search for PlsEtn resources in foodstuffs. The foodstuffs examined showed a wide range of PlsEtn contents from 5 to 549 μmol/100 g wet wt. The marine invertebrates, blue mussel, and ascidian had high PlsEtn contents (over 200 μmol/100 g wet wt). Profiling of the molecular species showed that the predominant fatty acids of PlsEtn species were 20:5 (EPA) and 22:6 (DHA) at the sn‐2 position of the glycerol moiety in marine foodstuffs, whereas major PlsEtn species in land foodstuffs were 20:4. Following quantitative analysis by multiple reaction monitoring, the ascidian viscera were shown to contain the highest levels of 18:0/20:5‐PlsEtn and 18:0/22:6‐PlsEtn (86 and 68 μmol/100 g wet wt, respectively). In order to evaluate a neuronal antiapoptotic effect of these PlsEtn species, human neuroblastoma SH‐SY5Y cells were treated with ethanolamine glycerophospholipid (EtnGpl), purified from the ascidian viscera, under serum starvation conditions. Extrinsic EtnGpl from ascidian viscera showed stronger suppression of cell death induced by serum starvation than with bovine brain EtnGpl. The EtnGpl from ascidian viscera strongly suppressed the activation of caspase 3. These results suggest that PlsEtn, especially that containing EPA and DHA, from marine foodstuffs is potentially useful for a therapeutic dietary supplement preventing neurodegenerative diseases, such as Alzheimer's disease (AD). 相似文献
70.
Tetsuo Sato Yasuhiro Takahata Takahiro Noda Takashi Yanagisawa Toshikazu Morishita Shinji Sakai 《Journal of the American Oil Chemists' Society》1995,72(10):1177-1183
Determination of the fatty acid composition of sunflower (Helianthus annua L.) seeds by near-infrared (NIR) spectroscopy was examined. Sunflower seeds were husked (removed from their hulls by a husking
machine or manually with a knife). NIR spectra of these seeds were scanned from 1100 to 2500 nm at 2-nm intervals in a whole-grain
cell with a wideangle moving drawer for machine-husked seeds or in a single-grain cup for a manually husked single-grain seed.
The extracted oils from machine-husked seeds also were scanned by sandwiching them between a pair of slide glasses to create
a thin layer and by placing them on a syrup cup. For extracted oil, the absorption band around 1720 nm filled out to the shorter
wavelength region in the NIR second-derivative spectra as the percentage of the linoleic acid moiety increased, because linoleic
acid absorbs in this region. On the other hand, for husked seeds and for a single-grain seed, as the percentage of linoleic
acid increased, the trough at 1724 nm where oleic and saturated acids absorb decreased in the second-derivative NIR spectra.
Determination of the fatty acid composition of sunflower seeds could be carried out successfully according to the NIR spectral
pattern for both extracted oil (r=−0.989) and kernel seed (r=−0.993). This is important, especially for a manually husked
single-grain seed (r=−0.971), because it can still be germinated after such nondestructive analysis. 相似文献