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排序方式: 共有715条查询结果,搜索用时 178 毫秒
81.
Makio Iwahashi Tadashi Nozaki Kazuyuki Kamaya Kenichi Taguchi Masahiro Fujita Yasutoshi Kasahara Hideyuki Minami Hideyo Matsuzawa Shinji Nakamura Katsuyoshi Harada Yukihiro Ozaki Tohru Inoue 《The Journal of chemical thermodynamics》2011,43(1):80-87
Phase behaviors of the binary mixtures composed of ethylene carbonate (EC) and aliphatic alcohols, ω-phenyl alcohols, and alkylbenzenes were investigated. In addition, heat of solution of EC into these organic solvents was measured. The EC/methanol and EC/ethanol systems gave homogeneous solution at the temperature above their liquidus lines, while the mixtures of EC and alcohols with longer alkyl chain showed a miscibility gap in a liquid phase and provided the monotectic-type phase diagram. The liquid–liquid phase separation region expanded with the increase in the alkyl chain length. A similar phase behavior was also observed for the mixtures of EC and alkylbenzenes. On the other hand, the EC mixtures with ω-phenyl alcohols showed no miscibility gap in a liquid phase at least up to 4-phenylbutan-1-ol which has C4 alkyl chain intervening between phenyl and hydroxyl groups. This result demonstrates that both of the hydroxyl and phenyl groups act to facilitate the mixing of aliphatic compounds with EC. The phase behavior of these EC mixtures was analyzed applying the modified regular solution model in which the pair interaction energy was regarded as free energy. The model calculation with the use of heat of solution of EC at infinite dilution as the pair interaction enthalpy reproduced well both of the experimentally obtained liquidus line and mutual solubility curve as well as monotectic point. 相似文献
82.
Chen L Han X Yang J Zhou J Song W Zhao B Xu W Ozaki Y 《Journal of colloid and interface science》2011,360(2):482-487
We have employed the proposed Silica-Silver Core-Shell (SSCS) SERS-active substrates to detect four model proteins: lysozyme (a protein without chromophore), cytochrome c (a protein with chromophore of heme), fluorescein isothiocyanate (FITC)-anti human IgG (labeled with FITC) and atto610-biotin/avidin (recognition with labeled small molecules). SERS spectra of these proteins and Raman labels on the SSCS substrates show both high sensitivity and reproducibility, which are due to electromagnetic SERS enhancement with additional localization field within closely packed Ag nanoparticles decorated on the SiO(2) nanoparticles and the aggregation of SiO(2)@Ag particles. We have found that the SERS intensities of atto610-biotin/avidin adsorbed on the SSCS substrates are about 20 times stronger than those from Ag plating on Au-decorated substrate. Moreover, the broad surface plasmon resonance (SPR) of the proposed substrates will extend SERS applications to more biological molecules with different laser excitations. 相似文献
83.
Koji Nakabayashi Masaki Kawano Prof. Dr. Tatsuhisa Kato Prof. Dr. Ko Furukawa Dr. Shin‐ichi Ohkoshi Prof. Dr. Toshiya Hozumi Dr. Makoto Fujita Prof. Dr. 《化学:亚洲杂志》2007,2(1):164-170
We show a new approach to manipulating the through‐space spin–spin interaction by utilizing the confined cavity of a self‐assembled M6L4 coordination cage. The coordination cage readily encapsulates stable organic radicals in solution, which brings the spin centers of the radicals closer to each other. In sharp contrast to the fact that the radical in solution in the absence of the cage is in a doublet state, in the presence of the cage through‐space spin–spin interaction is induced through cage‐encapsulation effects in solution as well as in the solid state, resulting in the triplet state of the complex. These results were confirmed by ESR spectroscopy and X‐ray crystallography. The quantity of triplet species generated by encapsulation in the cage increases with increasing affinity of the radicals to the cage. We estimated the affinity between several types of guests and the cage in solution by cyclic voltammetry. We also demonstrate that the through‐space interaction of organic radicals within the self‐assembled coordination cage can be controlled by external stimuli such as heat or pH. 相似文献
84.
Ze‐Kun Yang Dong‐Yu Wang Hiroki Minami Hiroyuki Ogawa Takashi Ozaki Dr. Tatsuo Saito Dr. Kazunori Miyamoto Dr. Chao Wang Prof. Dr. Masanobu Uchiyama 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(44):15693-15699
Various aryl‐, alkenyl‐, and/or alkyllithium species reacted smoothly with aryl and/or benzyl ethers with cleavage of the inert C?O bond to afford cross‐coupled products, catalyzed by commercially available [Ni(cod)2] (cod=1,5‐cyclooctadiene) catalysts with N‐heterocyclic carbene (NHC) ligands. Furthermore, the coupling reaction between the aryllithium compounds and aryl ammonium salts proceeded under mild conditions with C?N bond cleavage in the presence of a [Pd(PPh3)2Cl2] catalyst. These methods enable selective sequential functionalizations of arenes having both C?N and C?O bonds in one pot. 相似文献
85.
Asymmetric Induction by a Nitrogen 14N/15N Isotopomer in Conjunction with Asymmetric Autocatalysis 下载免费PDF全文
Dr. Arimasa Matsumoto Hanae Ozaki Shunya Harada Kyohei Tada Tomohiro Ayugase Hitomi Ozawa Prof. Dr. Tsuneomi Kawasaki Prof. Dr. Kenso Soai 《Angewandte Chemie (International ed. in English)》2016,55(49):15246-15249
Chirality arising from isotope substitution, especially with atoms heavier than the hydrogen isotopes, is usually not considered a source of chirality in a chemical reaction. An N2,N2,N3,N3‐tetramethyl‐2,3‐butanediamine containing nitrogen (14N/15N) isotope chirality was synthesized and it was revealed that this isotopically chiral diamine compound acts as a chiral initiator for asymmetric autocatalysis. 相似文献
86.
S Ozaki T Akiyama T Morita M Kumegawa T Nagase N Uehara A Hoshi 《Chemical & pharmaceutical bulletin》1990,38(11):3164-3166
Various kinds of 5'-O-unsaturated acyl 5-fluorouridines were synthesized to obtain 5-fluorouridine derivatives with low toxicity and high antitumor activity. Antitumor activity of the compounds against L-1210 leukemia in mice was examined, and the 5'-O-4-pentenoyl derivative showed the highest antitumor activity. 相似文献
87.
Hideo Kojima Kazuyoshi Ozaki Noboru Matsumura Hiroo Inoue 《Journal of heterocyclic chemistry》1990,27(6):1845-1846
7-Substituted 2,3-bis(isopropylthio)naphth[1,8-bc]azepines 3a-c were synthesized in good yields by the reactions of 5-substituted 1-naphthylamines 2a-c with tris(isopropylthio)cyclopropenylium perchlorate ( 1 ) in acetonitrile under reflux. This reaction proceeds through the facile ring opening of 1 , followed by the intermediary formation of iminium salts 5a-c and then intramolecular cyclization. 相似文献
88.
Self-association system of(R)-1,3-butanediol in dilute carbon tetrachloride(CCl4)solution is studied as a model of molecular association mixture.Analysis methods including FSMWEFA(fixed-size moving window evolving factor analysis)combined with PCA(principal component analysis),SIMPLISMA (simple-to-use interactive self-modeling mixture analysis),and ITTFA(iterative target transformation factor analysis)are adopted to resolve infrared spectra of(R)-1,3-butanediol solution.Association number and equilibrium constant are computed.(R)-1,3-butanediol in dilute inert solution is determined as a monomer-trimer equilibrium system.Theoretical investigation of trimer structures is carried out with DFT(density functional theory),and structural factors are analyzed. 相似文献
89.
Tomohiro Nuida Toshiya Hozumi Hiroko Tokoro Kazuhito Hashimoto Shin-ichi Ohkoshi 《Journal of Solid State Electrochemistry》2007,11(6):763-772
This article describes novel optical functionalities such as photomagnetic effects and magnetization-induced second harmonic
generation (MSHG) in several cyano-bridged metal assemblies. Single crystal- and film-types of a cyano-bridged Cu–Mo bimetallic
assembly, , were electrochemically prepared. When this compound was irradiated with light, spontaneous magnetization with a Curie temperature
(T
C) of 23 K was observed. Electrochemically prepared FeII[CrIII(CN)6]2/3·5H2O thin film, which was a ferromagnet with T
C=21 K, showed photoreduced magnetization. This photomagnetism is due to the change of ferromagnetic coupling between FeII and CrIII. MSHG was observed in CsICoII[CrIII(CN)6]·0.5H2O. This -type Prussian blue analog-based magnet is proven to be a piezoelectric ferromagnet, i.e., condensed matter with both piezoelectric
and ferromagnetism. This MSHG is due to the coupling between a piezoelectric structure of and ferromagnetism with a T
C of 46 K.
相似文献
Shin-ichi OhkoshiEmail: |
90.
Jiang Y Wang Z Xu H Chen H Zhang X Smet M Dehaen W Hirano Y Ozaki Y 《Langmuir : the ACS journal of surfaces and colloids》2006,22(8):3715-3720
This article describes the preparation of pH-responsive self-assembled monolayers (SAMs) of acylated anthranilate-terminated alkanethiol. These monolayers are formed by chemisorption of the alkanethiol molecules onto a gold surface, resulting in different wetting properties of the surfaces depending upon the pH. By using various characterization techniques (e.g., infrared spectroscopy, cyclic voltammetry, contact angle measurements, and surface energy analysis), we have found that the changes in the wetting properties originate from the different surface structures of the monolayers in different pH environments. From surface energy analysis, we found that the disperse components of the surface energy on such SAMs predominate after treatment with pH 1 water, whereas the polar components of the surface energy on such SAMs predominate after treatment with pH 13 water. It is greatly anticipated that this line of research will provide new insight into the mechanism behind pH-responsive properties, facilitating the design and synthesis of new surface-active molecules for the fabrication of pH-responsive functional surfaces. 相似文献