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51.
The modulation of the real part of the non-linear refractive index (Δn) associated with the giant two-photon absorption (GTA) band of the excitonic molecules (EM's) has been measured in CuCl at 1.6K. This has been measured by the observation of the polarization rotation effects due to the induced optical anistropy between the right circularly polarized (σ+) and the left circularly polarized (σ-) components of the linearly polarized probe team of Ω1 under the strong irradiation of the σ- beam of Ω2 fixed around the GTA band at 3.1861 eV. The maximum amount of Δn has been 2.9×10-4 at 3.1920 eV under the maximum excitation level when Ω2 has been fixed at 3.1796 eV. The experimental results have been discussed in terms of the renormalization of the polaritons due to the real and virtual formation of EM's. 相似文献
52.
A method of measuring flow-birefringence is reported. In this method, a circularly polarized light wave is transmitted through the flow-birefringent medium. The transmitted elliptically polarized wave is compensated by a Babinet-Soleil plate to convert it back into a circularly polarized wave. The state of circular polarization is confirmed using the rotating-analyser method. Measurements can be carried out with a sample having a fixed azimuth. The minimum detectable optical retardation angle was 5 × 10-3 degree. This corresponds to a birefringence of Δn = 1 × 10-10, when the optical path length of the sample cell is 100 mm. 相似文献
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The temperature dependences of the elastic constants, c11, c33, c44, and c66, in KCP are described. In the temperature range 10–100 K softening is observed in c44, while c66 decreases almost linearly with decreasing temperature. These results indicate the presence of a new critical region. 相似文献
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Hiyoshizo Kotsuki Yoshikatsu Ichikawa Mitsuhiro Iwasaki Masanori Kataoka Hitoshi Nishizawa 《高压研究》2013,33(1-3):107-118
Abstract A variety of cyclic and acyclic ethers are efficiently reacted with acyl chlorides or acyl bromides to afford the ether-cleaved compounds of ω-chloro-or ω-bromoesters under high pressure conditions. The reactivity of ethers is found to be roughly depend on the basicity of the ether oxygen atom. 相似文献
58.
We have performed electroabsorption spectroscopy on micelle-wrapped single-wall carbon nanotubes. In semiconducting nanotubes, many oscillating structures composed of the increase and decrease of absorption are observed in the spectra in the region of the first and second absorption bands, E11 and E22. The spectral shape is reproduced mainly by the second-derivative curve of the absorption spectrum, which indicates the presence of nearly degenerate bright and dark excitonic states. 相似文献
59.
Effects of polyethylene spacer length in polymeric electrolytes on gelation of ionic liquids and ionogel properties
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Jun'ichi Nagasawa Sonoko Wakahara Hajime Matsumoto Hideyuki Kihara Masaru Yoshida 《Journal of polymer science. Part A, Polymer chemistry》2015,53(2):249-255
Polymer electrolytes containing N,N′-(trans-cyclohexane-1,4-diyl)dibenzamide linkages, polyethylene ((CH2)m, m = 2, 4, 10) spacers, and bis(trifluoromethanesulfonyl)amide (TFSA) or bis(fluorosulfonyl)amide (FSA) counteranions (polymer abbreviation: CDBAm•X; m = 2, 4, 10; X = TFSA, FSA) have been synthesized, adding to our previous report (m = 6). In addition, their ability to effect the gelation of six ionic liquids and the properties of the resulting ionogels have been examined. The polymers, except for CDBA10•TFSA, effect the gelation for all ionic liquids used in this study at fairly low concentrations (0.9–50 g/L). Ionogel ionic conductivity is not dependent on the spacer length, but does decrease slightly as increasing amounts of the gelatinizer are introduced. In contrast to ionic conductivity, the temperatures at which these ionogels transition into isotropic fluids is dependent on the spacer length; the gel composed of [EMI][FSA] and 100 g/L of CDBA6•FSA transforms at 120 °C, while the gel composed of [EMI][FSA] and 5 g/L of CDBA2•FSA does not transform into a sol even when temperatures become 155 °C. In brief, ionogel heat resistance can be improved by changing the spacer length of the polyelectrolyte. Finally, it has been determined using cyclic voltammetry that the potential window of the polyelectrolytes is particularly wide, ranging from −1.6 to 2.5 V. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 249–255 相似文献
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Kanna Adachi Tomoshi Yamada Hayate Ishizuka Mana Oki Shunsuke Tsunogae Noriko Shimada Osamu Chiba Tatsuya Orihara Prof. Dr. Masafumi Hidaka Prof. Dr. Takatsugu Hirokawa Dr. Minami Odagi Prof. Dr. Keiichi Konoki Prof. Dr. Mari Yotsu-Yamashita Prof. Dr. Kazuo Nagasawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(9):2025-2033
A novel series of C12-keto-type saxitoxin (STX) derivatives bearing an unusual nonhydrated form of the ketone at C12 has been synthesized, and their NaV-inhibitory activity has been evaluated in a cell-based assay as well as whole-cell patch-clamp recording. Among these compounds, 11-benzylidene STX ( 3 a ) showed potent inhibitory activity against neuroblastoma Neuro 2A in both cell-based and electrophysiological analyses, with EC50 and IC50 values of 8.5 and 30.7 nm , respectively. Interestingly, the compound showed potent inhibitory activity against tetrodotoxin-resistant subtype of NaV1.5, with an IC50 value of 94.1 nm . Derivatives 3 a – d and 3 f showed low recovery rates from NaV1.2 subtype (ca 45–79 %) compared to natural dcSTX ( 2 ), strongly suggesting an irreversible mode of interaction. We propose an interaction model for the C12-keto derivatives with NaV in which the enone moiety in the STX derivatives 3 works as Michael acceptor for the carboxylate of Asp1717. 相似文献