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991.
Ryousuke Yoshii Dr. Atsushi Nagai Dr. Kazuo Tanaka Prof. Yoshiki Chujo 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(14):4506-4512
A series of boron ketoiminate derivatives that exhibited clear aggregation‐induced emission (AIE) characteristics (in THF: ΦPL≤0.01; in the solid state: ΦPL=0.30–0.76) were prepared by the reactions of 1,3‐enaminoketone derivatives with boron trifluoride–diethyl etherate. The structures and optical properties were investigated by UV‐visible spectroscopy, photoluminescent (PL) spectroscopy, and X‐ray single‐crystal measurements. These results indicate that the AIE characteristics were derived from molecular motions of the boron‐chelating rings with a boron? nitrogen (B? N) bond. Furthermore, the optical properties were controllable by steric hindrance of the substituted groups on the nitrogen atom. 相似文献
992.
Takayuki Iijima Masahiro Abe Take‐Aki Koizumi Atsushi Fukaya Kyohei Usami Kenichiro Kami Takakazu Yamamoto 《先进技术聚合物》2013,24(10):927-933
The reaction of 2,5‐diiodo‐1,4‐benzenedicarbonyl chloride, C6H2I2(COCl)2‐p, with 4‐hydroxy‐2,2,6,6‐tetramethyl‐1‐piperidinyloxy (TEMPO‐ol) gave I–Ph(COO–TEMPO)2–I, Monomer‐1. Pd‐catalyzed polycondensation of Monomer‐1 with Me3Sn‐Th‐SnMe3 (2,5‐bis(trimethylstannyl)thiophene) and Bu3Sn–CH = CH–SnBu3 (1,2‐bis‐(tributylstannyl)ethylene) gave the corresponding π‐conjugated polymers, Polymer‐1 and Polymer‐2, respectively. Monomer‐1 was converted to a diethynyl compound, H–C ≡ C–Ph(COO–TEMPO)2–C ≡ C–H (Monomer‐1'), and Pd‐catalyzed polycondensation between Monomer‐1 and Monomer‐1' gave a π‐conjugated poly(arylene ethynylene) type polymer, Polymer‐3. According to the expansion of the π‐conjugation system by the polymerization, the UV–vis peaks of Monomer‐1 (λmax = 323 nm) and Monomer‐1' (327 nm) are shifted to longer wavelengths (λmax = 365 nm, 385 nm, and 396 nm for Polymer‐1, Polymer‐2, and Polymer‐3, respectively). Polymer‐1–Polymer‐3 showed ESR signals at about g = 2.01 with reasonable intensities. They are electrochemically active and showed a peak current anodic (oxidation) peak at about 0.9 V versus Ag/AgCl, which is reasonable for TEMPO polymers. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
993.
994.
Atsushi Yamamoto Tetsuya Hasegawa Tomoya Hamada Tomofumi Hirukawa Dr. Ichiro Hisaki Prof. Dr. Mikiji Miyata Dr. Norimitsu Tohnai 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(9):3006-3016
A diamondoid porous organic salt (d‐POS) composed of 8‐hydroxyquinoline‐5‐sulfonic acid (HQS) and triphenylmethylamine (TPMA) shows reversible structure contraction and expansion (“breathing”) in response to guest desorption and adsorption. This flexible structure is designed hierarchically by utilizing two different types of hydrogen bonds. X‐ray crystallographic analysis reveals that the two types of hydrogen bonds are formed separately to play respective roles for constructing the d‐POS. The strong charge‐assisted hydrogen bond between the sulfonate anion of HQS and the ammonium cation of TPMA serves as a static node to provide a supramolecular cluster for a building block. In contrast, the complementary neutral hydrogen bond between the hydroxyl and quinolyl groups of HQS acts as a dynamic linker to connect the clusters. Consequently, these two types of hydrogen bonds yield the d‐POS with one‐dimensional channels through the formation of diamondoid networks. We clarify that the d‐POS undergoes dynamic structure transformation that originates in the cleavage and reformation of the complementary neutral hydrogen bond during guest desorption and adsorption. From the comparative studies, it is also demonstrated that applying the complementary neutral hydrogen bond in the d‐POS provides significant advantages in terms of the responsivity of the structure over applying other weak noncovalent interactions for the connection of the clusters. Furthermore, the resultant d‐POS also modulates fluorescent profiles dynamically responsive to guest adsorption and desorption. 相似文献
995.
996.
Atsushi Hyono Tetsu Yonezawa Koji Kawai Shigeaki Abe Mitsuhiro Fujihara Hiroshi Azuma Shinobu Wakamoto 《Surface and interface analysis : SIA》2014,46(6):425-428
In this study, we succeed in visualizing a ‘living’ morphology of red blood cells (RBCs) by a rapid and simple scanning electron microscope (SEM) pretreatment using a hydrophilic room temperature ionic liquid (RTIL) with asymmetrical structure. The conventional pretreatment induces size shrinkage of the cells, and the diameter observed in an SEM (less than 6 µm) was smaller than that in an optical microscope (8 µm). Though RBCs are well‐known to be easily deformed with the environmental conditions, the cells did not show the deformation when they were pretreated with our RTILs. Since the chemical structure of our RTIL resembles a ‘choline’, which is a typical bioactive material, and has biocompatibilities, they may make it avoid from the deformation of RBCs. In fact, only immersing RBCs, our novel RTIL can provide a clear SEM image without size shrinkage and deformation. Interestingly, the obtained SEM image shows 8 µm in the diameter, almost same size as that in optical microscope. Therefore, this method is expected for novel SEM pretreatment for various biological samples observation as ‘living’ matter. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
997.
Designs, Codes and Cryptography - Revocable identity-based encryption (RIBE) is an extension of IBE that satisfies a key revocation mechanism to manage a number of users dynamically and... 相似文献
998.
Atsushi Makino R. Higuchi A. Hisamoto K. Koizumi H. Takada 《Proceedings of the Combustion Institute》2011,33(2):1967-1974
Spontaneous ignition of compacted mixture has been examined not only experimentally but also theoretically, relevant to materials synthesis by combustion for Ti–Al system. By varying compact and particle sizes, mixture ratio, and degree of dilution, spontaneous ignition temperature has been measured, which is determined from the inflection-point of the temporal variations of the surface temperature. It is found that the spontaneous ignition temperature decreases with increasing aspect ratio, defined as the ratio of the sample height and compact diameter, due to an establishment of the stationary temperature distribution in the radial direction in the compacted mixture, as the sample height becomes tall. It is also found that the spontaneous ignition temperature decreases with increasing size ratio, defined as the ratio of compact and particle diameters, due to an increase in the particle surface per unit spatial volume of the compacted mixture, caused by a decrease in the particle diameter and/or an increase in the compact diameter. By further examining its dependence on mixture ratio and/or degree of dilution, it is confirmed that the limit of flammability also exerts influences on the spontaneous ignition temperature. In addition, a fair degree of agreement, shown in experimental comparisons with theoretical results, indicates that the present formulation has captured the essential features of the spontaneous ignition of compacted mixture. Since this kind of particle size effect, especially, relevant to the spontaneous ignition of compacted mixtures, has not been captured in the previous studies, its elucidation can be considered not only notable but also useful, especially, in manipulating combustion process in materials synthesis. 相似文献
999.
Atsushi Shiho 《Selecta Mathematica, New Series》2011,17(4):833-854
Let
X \hookrightarrow[`(X)]{X \hookrightarrow \overline{X}} be an open immersion of smooth varieties over a field of characteristic p > 0 such that the complement is a simple normal crossing divisor and [`(Z)] í Z í [`(X)]{\overline{Z}\subseteq Z \subseteq \overline{X}} closed subschemes of codimension at least 2. In this paper, we prove that the canonical restriction functor between the categories
of overconvergent F-isocrystals F-Isocf(X,[`(X)]) ? F-Isocf(X\Z,[`(X)]\[`(Z)]){F-{\rm Isoc}^\dagger(X,\overline{X}) \longrightarrow F-{\rm Isoc}^\dagger(X{\setminus}Z, \overline{X}{\setminus}\overline{Z})} is an equivalence of categories. We also give an application of our result to the equivalence of certain categories. 相似文献
1000.
Takashi Ui Hiroyuki Kojima Atsushi Kajii 《Mathematical Methods of Operations Research》2011,74(3):427-443
In order to describe partial cooperation structures, this paper introduces complete coalition structures as sets of feasible
coalitions. A complete coalition structure has a property that, for any coalition, if each pair of players in the coalition
belongs to some feasible coalition contained in the coalition then the coalition itself is also feasible. The union stable
structures, which constitute the domain of the Myerson value, are a special class of the complete coalition structures. As
an allocation rule on complete coalition structures, this paper proposes an extension of the Myerson value for complete coalition
structures and provides an axiomatization. 相似文献