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71.
Takako Takahashi 《Journal of polymer science. Part A, Polymer chemistry》1968,6(2):403-414
1,5-Type polymerization of vinylcyclopropane proceeding by the opening of both the double bond and the cyclopropane ring was found. Some other vinylcyclopropane derivatives, 1,1-dichloro-2-vinylcyclopropane, 1,1-dibromo-2-vinylcyclopropane, isopropenylcyclopropane, 1-methyl-1-vinylcyclopropane, 1,1-dichloro-2-methyl-2-vinylcyclopropane, and cis- and trans-1-chloro-2-vinylcyclopropane, were investigated. The observation of infrared spectra, NMR spectra, and other data indicated that the radical polymerization of these compounds gave principally 1,5-type polymer, while in cationic polymerization 1,2-type was predominant. The behavior of the polymerization was discussed in terms of the stability of a cyclopropylcarbinyl ion or radical which is formed in the initiation and propagation steps. 相似文献
72.
Kanazawa H Okada A Igarashi E Higaki M Miyabe T Sano T Nishimura R 《Journal of chromatography. A》2004,1031(1-2):213-218
This study demonstrated the analysis of midazolam and its metabolites by liquid chromatography-mass spectrometry (LC-MS) with a sonic spray ionization (SSI) interface. The analytical column was a YMC-Pak Pro C18 (50 mm x 2.0 mm i.d.) using 10 mM ammonium acetate (pH 4.8)-methanol (1:1) at a flow rate of 0.2 ml min(-1). The drift voltage was 100 V. The sampling aperture was heated at 110 degrees C and the shield temperature was 230 degrees C. The lower limits for the detection of midazolam and 1'-hydroxymidazolam were 26.3 and 112.76 pg injected, respectively. The calibration curves for midazolam and 1'-hydroxymidazolam were linear in the range of 0.1-5 microg ml(-1). Within-day relative standard deviations was less than 7%. The method was applied to the determination of midazolam in monkey plasma, and the analysis of midazolam and its metabolites in an in vitro study with recombinant cytochrome P450 (CYP) 3A4. This method is sufficiently sensitive and useful to elucidate the kinetics of midazolam metabolite formation. We also investigated the effect of propofol on the metabolism of midazolam using recombinant CYP3A4. Propofol competitively inhibited the metabolism of midazolam to 1'-hydroxymidazolam by CYP3A4. 相似文献
73.
Masataka Mochizuki Takako Anjo Yuko Wakabayashi Toshie Sone Masashi Okada 《Tetrahedron letters》1980,21(18):1761-1764
N-alkyl-N-(1-hydroperoxyalkyl)nitrosamines were prepared by treatment of the corresponding 1-acetoxyalkyl nitrosamines with hydrogen peroxide in acetic acid through an acid-catalyzed nucleophilic substitution. 相似文献
74.
75.
Daisuke Ishikawa Yuki Suzuki Chikako Kurokawa Masayuki Ohara Misato Tsuchiya Masamune Morita Miho Yanagisawa Masayuki Endo Ryuji Kawano Masahiro Takinoue 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(43):15443-15447
Bio‐inspired functional microcapsules have attracted increasing attention in many fields from physical/chemical science to artificial‐cell engineering. Although particle‐stabilised microcapsules are advantageous for their stability and functionalisation potential, versatile methods for their functionalisation are desired to expand their possibilities. This study reports a water‐in‐oil microdroplet stabilised with amphiphilic DNA origami nanoplates. By utilising DNA nanotechnology, DNA nanoplates were designed as a nanopore device for ion transportation and to stabilise the oil–water interface. Microscopic examination revealed the microcapsule formed by the accumulation of amphiphilic DNA nanoplates at the oil–water interface. Ion current measurements revealed the nanoplate pores functioned as channel to transport ions. These findings provide a general strategy for the programmable design of microcapsules to engineer artificial cells and molecular robots. 相似文献
76.
The effect of inorganic salts with different charge numbers of cations on the adsorption and micelle formation of dodecylammonium chloride (DAC) was clarified by applying the thermodynamic treatment of surfactant mixtures to mixtures of DAC with calcium and lanthanum chlorides and comparing the results with those of the sodium chloride-DAC mixture in the previous study. Surface tension of aqueous solutions of the salt-DAC mixture was measured as a function of the total molality of the mixture and the mole fraction of DAC in the mixture at 298.15 K under atmospheric pressure. Judging from the phase diagrams of adsorption and micelle formation obtained from the surface tension measurement, dodecylammonium cations expel inorganic cations from the adsorbed film and micelle and the repulsive interaction between dodecylammonium and inorganic cations increases with increasing charge number of the inorganic cation. 相似文献
77.
Kamino S Horio Y Komeda S Minoura K Ichikawa H Horigome J Tatsumi A Kaji S Yamaguchi T Usami Y Hirota S Enomoto S Fujita Y 《Chemical communications (Cambridge, England)》2010,46(47):9013-9015
A new class of rhodamine luminophores, 3',3'-bis(oxospiroisobenzofuran)-3,7-bis(dialkylamino)benzopyrano-xanthene derivatives (ABPX), have been successfully developed. The emission behavior of ABPX series is directly opposite to the concentration quenching of conventional rhodamine dyes. ABPX series exhibit aggregation-induced emission enhancement (AIEE). 相似文献
78.
Yui T Kobayashi Y Yamada Y Tsuchino T Yano K Kajino T Fukushima Y Torimoto T Inoue H Takagi K 《Physical chemistry chemical physics : PCCP》2006,8(39):4585-4590
Photochemical Electron Transfer (ET) between an organic dye, the porphyrin derivative TMPyP, and an electron acceptor, methyl viologen MV2+, have been investigated at the interface of two different inorganic films, i.e., layered titania nano-sheets (TNS) and a monolayer film of spherical and mono-dispersed mesoporous silica (sMPS) particles (ca. 0.5 microm). TMPyP ions were intercalated within the sMPS nano-cavities to form (TMPyP-sMPS) while MV2+ ions were intercalated into the TNS interlayers to form (MV2+-TNS). The (TMPyP-sMPS) and (MV2+-TNS) films were then stacked on a silica substrate in this order to form a (MV2+-TNS)/(TMPyP-sMPS) film and, upon UV light irradiation, ET could be induced. However, when this film was stacked inversely, i.e., for the (TMPyP-sMPS)/(MV2+-TNS) films on a silica substrate, no photoinduced ET were observed. Interestingly, however, even for this photo-inactive inversely stacked film, ET could be generated by inserting a gold vapor-deposited layer between the (MV2+-TNS) and (TMPyP-sMPS) films. The conjugation conditions at the interface of the inversely stacked (TMPyP-sMPS)/(MV2+-TNS) hybrid film were, thus, confirmed to strongly affect the photoinduced electron transfers and their efficiencies. 相似文献
79.
Itsuo Mori Takako Matsuo Yoshikazu Fujita Minako Toyoda Kenichi Ichitani Noriko Inoue 《Fresenius' Journal of Analytical Chemistry》1994,348(5-6):346-349
Summary A spectrofluorophotometric determination of thallium(III) is proposed. It is based on the enhancement of the fluorescence reaction of 3,4,5,6-tetrachlorofluorescein (TCF) with Pyrogallol Red (PR) by thallium(III) in the presence of Swanol (AM 301, lauryldimethyl aminoacetic acid betain) as an amphoteric surfactant. The method was found to be suitable for the determination of thallium(III) down to 4.0 g in 10.0 ml by measuring the difference in the relative fluorescence intensities of a TCF/PR/thallium(III) solution and a TCF/PR solution. The recovery test in artificial urine was satisfactory (96±2%). 相似文献
80.
Ultrasonic absorption and velocity measurements in aqueous solution of iso-butyl cellosolve (ethylene glycol iso-butyl ether) as a function of the concentration are reported. The two relaxational absorptions have been attributed to the perturbation of the equilibria expressed by AB?A+B and Aα(1/n)An where A is the solute, B is the solvent, AB is the complex and A n is the solute aggregate. The rate constants for each step have been determined. From the concentration dependence of the maximum excess absorption per wave length, the enthalpy change and the volume change for the reaction between the solute and the solvent have been determined for aqueous solutions of butyl cellosolve (ethylene glycol n-butyl ether), iso-butyl cellosolve and propyl cellosolve (ethylene glycol n-propyl ether). The results are consistent with a hydrogen bonding reaction. The effect of the ethers on water structure are considered and it is clear that the fraction of water molecules which can hydrogen bond to the solute decreases with the increasing hydrophobicity of the solute. 相似文献