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51.
Yamaguchi A Uejo F Yoda T Uchida T Tanamura Y Yamashita T Teramae N 《Nature materials》2004,3(5):337-341
A mesoporous membrane composed of nanochannels with a uniform diameter has a potential use for precise size-exclusive separation of molecules. Here, we report a novel method to form a hybrid membrane composed of silica-surfactant nanocomposite and a porous alumina membrane, by which size-selective transport of molecules across the membrane becomes possible. The nanocomposite formed inside each columnar alumina pore was an assembly of surfactant-templated silica-nanochannels with a channel diameter of 3.4 nm; the channel direction being predominantly oriented along the wall of the columnar alumina pore. Molecules could be transported across the membrane including the silica-surfactant nanocomposite with a capability of nanometre-order size-exclusive separation. Our proposed membrane system has a potential use not only for separation science, but also catalysis and chip technologies. 相似文献
52.
A novel methodology, a probe-regulated simultaneous separation using capillary electrophoresis (CE-PRESS), was developed for simultaneous assay of multiple genes. The single-stranded (ss) DNA-polymer conjugate-probes were placed in a capillary, and then a mixture of target ssDNAs was injected. These ssDNAs were hybridized with corresponding complementary ssDNA-polymer conjugate-probes after charging the capillary. Two resulting double-stranded (ds) complexes of ssDNAs and ssDNA-polymer conjugate-probes were detected at different migration times. We found that the electrophoretic mobilities of two ssDNA-poly(acrylamide) conjugate-probes [-(5'-GCCACCAGC-3')m-AAm(n)- and -(5'-ACCTTCACT-3')p-AAm(q)-; AAm, acrylamide] obtained by copolymerizing 5'-methacryloyl-modified ssDNA and AAm were different, depending on their molar fraction of ssDNA, although the ssDNAs chain lengths were the same. Two ssDNAs (5'-GCTGGTGGC-3' and 5'-AGTGAAGGT-3') having the same chain length were successfully separated with our novel system, although the separation of these ssDNAs is impossible in conventional capillary electrophoresis systems. 相似文献
53.
Profile structure of magnetic flux lines in type-II superconductor from a rectangular electron hologram 总被引:1,自引:0,他引:1
Harada K Beleggia M Endo J Kasai H Togawa Y Matsuda T Tonomura A 《Journal of electron microscopy》2003,52(4):369-373
Profile magnetic configuration of a quantized flux line and flux-line lattice penetrating a type-II superconductor thin foil, niobium, was observed by electron holography and Lorentz microscopy using a 300 kV field-emission electron microscope. Each single flux line was distributed periodically as lattice structure in the mixed state just below its critical temperature of 8.5 K, while at low temperature of 5 K the flux lines were weakly bound as bundles. In order to observe the flux-line distribution over a wide area, discrete Fourier transform reconstruction in the holography was extended for a rectangular area without loss of information and data precision. 相似文献
54.
55.
Shigeyuki Nagata Kengo Fukuzawa Yukio Iwashita Akira Kabashima Tadahiko Kinoshita Kenzo Wakasugi Yoshihiko Maehara 《Nutrition journal》2009,8(1):24-8
Background
Many clinical studies have demonstrated that early postoperative enteral nutrition (EN) improved the postroperative course. Post-pancreaticoduodenectomy (PD), patients tend to suffer from postoperative nausea, abdominal distention, and diarrhoea, causing difficulty in the introduction of EN. In this pilot study, we investigated the appropriate nutritional mode post-pancreatic surgery. 相似文献56.
Keiji Tsukada Mitsuteru Yoshioka Yoshihiko Kawasaki Toshihiko Kiwa 《NDT & E International》2010,43(4):323-328
We have developed a magnetic flux leakage (MFL) system using magnetic resistive (MR) sensors for detecting two dimensional magnetic field components, and an induction coil that generates low magnetic field strengths and extremely low frequencies. The signal at each scanned measurement point (i) was divided by the signal strength Mmes,i and phase αi by a lock-in amplifier. Using the strength Mmes,i and phase αi, we calculated the imaginary part of the signal using the common phase β. By optimization of the common phase β to the imaginary part, the analyzed scanning data curve was shown to be effective in estimating the size (depth and diameter) of back-side pits on a ferrous plate. Comparing the two dimensional magnetic field components of leakage, the imaginary part of the y-component parallel to the induced magnetic field was found to be suitable for detecting the back-side pits. 相似文献
57.
Hiroyuki Hamada Hiroyuki Kato Naoto Ito Yoshihiko Takase Hironobu Nanbu Shoko Mishima Hiromu Sakaki Kiyotaka Sato 《European Journal of Lipid Science and Technology》2010,112(12):1323-1330
Biodiesel fuels (BDF) have many problems in the cold due to their crystallization properties. In particular, precipitation of large crystals of high‐melting fractions in BDF at low temperatures remarkably changes cold flow property of BDF and, thereby, it increases the values of cold filter plugging point. In this study, we evaluated polyglycerol esters of fatty acids (PGE) and ethylene‐vinyl acetate co‐polymer (EVA) as chemical additives to improve the cold flow property of palm oil‐based FAME (PFME). The results of solid fat content measurement indicate that the simultaneous addition of PGE and EVA showed synergistic effects on suppression of crystallization of PFME, however such effect was not observed when EVA was used alone. DSC thermograms indicated that the PGE additives not only decreased the crystallization temperature but also kinetically suppressed the crystal growth. Polarized light microscopy showed that the simultaneous addition of PGE and EVA led to the formation of considerably small and fine‐dispersed crystals of PFME. These results indicate that combined effects of PGE and EVA caused the formation of fine‐dispersed PFME crystals, which could improve the viscous properties of palm oil‐based BDF at relatively cold temperatures. 相似文献
58.
Tomoya Nagira Shugo Morita Hiroyoshi Yokota Hideyuki Yasuda Christopher M. Gourlay Masato Yoshiya Akira Sugiyama Kentaro Uesugi Akihisa Takeuchi Yoshio Suzuki 《Metallurgical and Materials Transactions A》2014,45(12):5613-5623
Synchrotron X-ray radiography at 125 frames per second was used to study deformation mechanisms in semi-solid Fe-C alloys at high solid fraction and shear strain rates of 10?1/s. An image correlation approach was also used to quantify the shear strain fields and study shear-induced dilation and the origin of shear cracking. It was shown that, at high solid fraction (90 to 93 pct solid), rearrangement including rotation and translation of solid particles became restricted and shear strain localized into narrow liquid-filled channels/fissures. Shear cracking was shown to originate from inadequate liquid flow into the expanding spaces between solid particles caused by shear-induced dilation. At lower solid fraction (~85 pct solid), solid particles rearranged with a significantly higher component of rotation leading to more shear-induced dilation and a wider shear band. 相似文献
59.
Kihara Ken; Yagi Yoshihiko; Takeda Yuji; Kawahara Jun I. 《Canadian Metallurgical Quarterly》2011,37(1):168
When two targets (T1 and T2) are embedded in rapid serial visual presentation (RSVP), T2 is often missed (attentional blink, AB) if T2 follows T1 by less than 500 ms. Some have proposed that inhibition of a distractor following T1 contributes to the AB, but no direct evidence supports this proposal. This study examined distractor inhibition by assessing a distractor devaluation effect where inhibited items were evaluated less positively than controls. Experiments 1 and 2 showed that a distractor presented just after T1 was evaluated less favorably when T2 was misidentified, independently of stimulus characteristics. Experiment 3 produced distractor devaluation in T2 incorrect trials when the evaluated distractor was the second item after T1. In contrast, a distractor presented before T1 was not devaluated (Experiment 4). Experiment 5 demonstrated that participants could not recognize presented distractors after an RSVP task, rejecting the possibility that memorized distractors were devalued. Results show a relationship between the devaluation of distractors following T1 and the AB, providing the first direct evidence of the distractor inhibition during the AB. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Crystallization behaviours around the glass transition temperature in an amorphous Fe70Nb10B20 alloy were investigated by means of transmission electron microscopy. Dense bcc-Fe nanocrystals initially appeared as the primary phase, followed by the dense formation of the (Fe,Nb)23B6 nanocrystalline phase. The bcc-Fe nanocrystals were formed even by annealing at a temperature that is 38 K lower than the glass transition temperature. A difference of the low temperature behaviours between the present conventional amorphous alloy and a bulk metallic glass was discussed. 相似文献