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41.
Satoshi Someya Satoshi Yoshida Koji Okamoto Yan Rong Li Manabu Tange Mohammad Mezbah Uddin 《显形杂志》2010,13(1):41-47
Abstract
Droplets impinging on a hot surface that is near the Leidenfrost temperature were experimentally investigated. Ejection of jets from the top of the droplet was observed during the transient interaction between the droplet and a hot wall. We term this phenomenon jet ejection from droplets. When the bottom of the droplet initially impacts the hot surface, a jet is to be ejected from the top of the droplet. The jet ejection occurred only at low impact velocities and around the wetting limit temperature. It was not observed when droplets were dropped from large heights or when the surface was at a high temperature. 相似文献42.
Manabu Ishifune Ryuhei Suzuki Mikio Yamane Hiroyuki Tanabe Yuki Nakagawa Kumao Uchida 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(7):523-528
Acrylamide (AAm) was found to polymerize in a solution of poly(N‐isopropylacrylamide) (PNIPAAm) in water at around its lower critical solution temperature (LCST) (32°C) without any initiators. This phenomenon was specifically observed in aqueous solutions of the polymers having LCST such as PNIPAAm and poly(methylvinylether) (PMVE). AAm polymerized only when PNIPAAm and AAm were dissolved in water below LCST of PNIPAAm and then the solution was warmed up to the polymerization temperature (40°C). On the other hand, the polymerization of AAm did not proceed when AAm was added into aqueous PNIPAAm solution during and after the phase separation above 32°C. Furthermore the polymerizability of AAm was remarkably affected by the concentration and molecular weight of the PNIPAAm additives. Under the condition of lower PNIPAAm concentration (0.30 mol/L), the increase in the molecular weight of PNIPAAm considerably increased the molecular weight of the resulting PAAm but decreased the yield of PAAm. Under the condition of higher PNIPAAm concentration (0.60 mol/L) the polymerizability was not so affected by the molecular weight of PNIPAAm, while the molecular weight of PAAm formed by using higher molecular weight PNIPAAm was higher than those of PAAm formed by using lower molecular weight PNIPAAm. Moreover, the molecular weight of PAAm formed by the PNIPAAm induced polymerization of AAm was much higher than that of the polymer obtained by the radical polymerization using AIBN in THF or VA‐ 061 in water. 相似文献
43.
Kenichiro Todoroki Hiroki Hashimoto Kazuyuki Machida Miki Itoyama Tadashi Hayama Hideyuki Yoshida Hitoshi Nohta Manabu Nakashima Masatoshi Yamaguchi 《Journal of separation science》2013,36(2):232-238
In this study, we combined a column‐switching system with a fluorous scavenging derivatization method to develop a fully automated reagent peak‐free LC fluorescence detection protocol for the analysis of highly polar carboxylic acids. In this method, highly polar carboxylic acids were derivatized with fluorescent 1‐pyrenemethylamine in the presence of 1‐ethyl‐3‐(3‐dimethylaminopropyl)carbodiimide and 1‐hydroxy‐1H‐benzotriazole. Residual excess of the unreacted reagent was tagged with 2‐(perfluorooctyl)ethyl isocyanate and then removed selectively using a fluorous column‐switching system placed in front of an analytical reversed‐phase column. The signal of the fluorous‐tagged unreacted reagent was completely absent in the resulting chromatograms; therefore, it did not interfere with the quantification of each acid especially those eluted before 20 min. The detection limits (S/N = 3) for the examined acids were in the range from 4.0 to 22 fmol per injection. We have applied this method to comparative analysis of highly polar carboxylic acids in urine samples obtained from diabetes mellitus type‐II model mice and their control. 相似文献
44.
Unsymmetrical oxamides are conveniently synthesized in good yields by a new trapping reaction of unstable carbamoyl lithiums with isocyanates. 相似文献
45.
Nicolas Zigon Manabu Hoshino Shota Yoshioka Yasuhide Inokuma Makoto Fujita 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2015,127(31):9161-9165
Crystal structures of α‐humulene, a cyclic sesquiterpene, and its oxidized subproducts, were analyzed by the crystalline sponge method. Regio‐ and stereochemistry, including absolute configuration when a chiral oxidant was applied, and the stable conformations of all the scaffold‐related compounds were successfully determined for samples on a 5–50 μg scale. 相似文献
46.
Takafumi Osuga Takashi Murase Manabu Hoshino Makoto Fujita 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2014,126(42):11368-11371
A tray‐shaped PdII3AuI3 complex ( 1 ) is prepared from 3,5‐bis(3‐pyridyl)pyrazole by means of tricyclization with AuI followed by PdII clipping. Tray 1 is an efficient scaffold for the modular assembly of [3×n] AuI clusters. Treatment of 1 with the AuI3 tricyclic guest 2 in H2O/CH3CN (7:3) or H2O results in the selective formation of a [3×2] cluster ( 1 ⋅ 2 ) or a [3×3] cluster ( 1 ⋅ 2 ⋅ 1 ), respectively. Upon subsequent addition of AgI ions, these complexes are converted to an unprecedented Au3–Au3–Ag–Au3–Au3 metal ion cluster. 相似文献
47.
Adaptive lambda square dynamics simulation: An efficient conformational sampling method for biomolecules 下载免费PDF全文
A novel, efficient sampling method for biomolecules is proposed. The partial multicanonical molecular dynamics (McMD) was recently developed as a method that improved generalized ensemble (GE) methods to focus sampling only on a part of a system (GEPS); however, it was not tested well. We found that partial McMD did not work well for polylysine decapeptide and gave significantly worse sampling efficiency than a conventional GE. Herein, we elucidate the fundamental reason for this and propose a novel GEPS, adaptive lambda square dynamics (ALSD), which can resolve the problem faced when using partial McMD. We demonstrate that ALSD greatly increases the sampling efficiency over a conventional GE. We believe that ALSD is an effective method and is applicable to the conformational sampling of larger and more complicated biomolecule systems. © 2013 Wiley Periodicals, Inc. 相似文献
48.
Surface neural activity has been widely visualized using optical intrinsic signal imaging (OISI) from various cortical sensory areas. OISI of the cortical surface with a CCD camera gives integrated information across a depth of a few hundred micrometers. We visualize depth-resolved activation patterns of cat primary visual cortex by functional optical coherence tomography (fOCT). A comparison of the depth-integrated results of fOCT maps with the optical intrinsic signal profiles shows fairly good agreement. Our results reveal layer-specific activation patterns and indicate that the activation was not homogeneous. 相似文献
49.
50.
Yoshida Keiichiro Ishizuka Tomohiro Mizushima Chiharu Nishidate Izumi Kawauchi Satoko Sato Shunichi Sato Manabu 《Optical Review》2015,22(2):374-384
Optical Review - To evaluate multi-spectral images of the absorption and scattering properties in the cerebral cortex of rat brain, we investigated spectral reflectance images estimated by the... 相似文献