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431.
Poly(squarate)s (PPS-1 and PPS-2) were synthesized by the reaction of squaryl dichloride with hydroquinone for PPS-1 and with 2,5-diethoxy-1,4-bis(trimethylsilyloxy)benzene for PPS-2, and the ionic conductivities, thermal properties, and electrochemical and thermal properties of their polymer electrolytes
with LiN(CF3SO2)2 were investigated. The ionic conductivity increased with increasing the lithium salt concentration for the PPS-1–LiN(CF3SO2)2 electrolyte, and the highest ionic conductivities of 8.60 × 10−5 S/cm at 100 °C and 9.57 × 10−8 S/cm at 30 °C were found at the [Li] to [O] ratio of 2:1. And also, the ionic conductivity for the PPS-1–LiN(CF3SO2)2 electrolyte increased with an increase in the lithium salt concentration, reached a maximum value at the [Li] to [O] ratio
of 1:2, and then decreased. The highest ionic conductivity was to be 1.04 × 10−5 S/cm at 100 °C and 1.71 × 10−8 S/cm at 30 °C, respectively. Both polymer electrolytes exhibited relatively better electrochemical and thermal stabilities.
Addition of the PPS-1 as a plasticizer into the poly(ethylene oxide) (PEO)–LiN(CF3SO2)2 electrolyte system suppressed the crystallization of PEO, and improved the ionic conductivity at room temperature.
Invited paper dedicated to Professor W. Weppner on his 65th birthday. 相似文献
432.
Daiki Lee Hiroki Kondo Yui Kuwayama Kento Takahashi Shiho Arima Satoshi Omura Masaki Ohtawa Tohru Nagamitsu 《Tetrahedron》2019,75(24):3178-3185
It is clear that atpenins and their analogs are useful chemical tools for elucidation of complex II functionality and that they could act as lead compounds for the development of novel helminth complex II-specific inhibitors. Recently, we discovered 4-epi-atpenin A5 as a potent nematode complex II inhibitor during our SAR studies of atpenin A5. This result led us to embark on a concise total synthesis of 4-epi-atpenin A5. In this study, we describe the total synthesis of 4-epi-atpenin A5. Importantly, this was more concise and practical synthesis than our previous total synthesis of atpenin A5. 相似文献
433.
Anderson TM Cao R Slonkina E Hedman B Hodgson KO Hardcastle KI Neiwert WA Wu S Kirk ML Knottenbelt S Depperman EC Keita B Nadjo L Musaev DG Morokuma K Hill CL 《Journal of the American Chemical Society》2005,127(34):11948-11949
A terminal Pd-oxo unit is reported. The unit is encapsulated in a cavity defined by two [A-alpha-PW9O34]9- units fused together by one [WO(OH2)]4+ center and forms from Pd(II) in buffered media in the presence of O2. Both X-ray diffraction and EXAFS data are consistent with a Pd-oxo bond distance of ca. 1.65 A. 17O NMR studies confirm that the solid-state structure is maintained in solution. 相似文献
434.
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437.
Growth of submicrometer-scale rectangular parallelepiped rutile TiO2 films in aqueous TiCl3 solutions under hydrothermal conditions 总被引:7,自引:0,他引:7
Hosono E Fujihara S Kakiuchi K Imai H 《Journal of the American Chemical Society》2004,126(25):7790-7791
Evolution of a new morphology of rutile TiO2 films consisting of nearly single-crystalline parallelepipeds was achieved through hydrothermal treatments of aqueous TiCl3 solutions in the presence of NaCl. 相似文献
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439.
The infrared spectra of ethylenediamine hydrochloride, sulfate and their N-deuterium derivatives in water or heavy water were studied at various pH or pD and at various concentrations. The frequencies of the CH2 deformation vibration bands in the region 1500-1250 dm?1 were found to be sensitive to the conformation of the ethlenediamine molecule and mono- and diammonium ions. The behaviors of these bands indicate that in aqueous solution the ethylenediamine molecule takes the gauche form, the ethylenemonoamine monoammonium ion takes mostly the gauche form and the ethylenediammonium ion takes both the trans and gauche forms. 相似文献
440.
Structure of prumycin 总被引:3,自引:0,他引:3