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991.
Rajamani Rajmohan Geoffrey Vrla Hisanori Ueki Kappamveettil Sajna Toshiaki Takei Hiroyoshi Ohtsu Masaki Kawano Pothiappan Vairaprakash Kentaro Tashiro 《化学:亚洲杂志》2020,15(6):766-769
Self‐assembly of a series of dimetallic sequences constructed on a backbone with two successive tyrosine moieties ( Fmoc‐M 1 ‐M 2 ‐CO2H ) revealed that the resultant morphology is clearly dependent on the metal sequence, where Re‐containing sequences such as homometallic Fmoc‐Re‐Re‐CO2H specifically afforded amyloid‐like nanofibers. These findings further allowed to achieve the fibrillation of a longer metal sequence containing three different metals ( Fmoc‐Rh‐Pt‐Re‐Re‐CO2H ). Cyclic voltammetry of the fibrillated Fmoc‐Re‐Re‐CO2H demonstrated that the redox activity of the metal complexes in the sequence is preserved in the nanofibrous forms. 相似文献
992.
Yongbing Shen Goulven Cosquer Hiroshi Ito David C. Izuogu Alex J. W. Thom Toshiaki Ina Tomoya Uruga Takefumi Yoshida Shinya Takaishi Brian K. Breedlove Zhao‐Yang Li Masahiro Yamashita 《Angewandte Chemie (International ed. in English)》2020,59(6):2399-2406
The first three‐dimensional (3D) conductive single‐ion magnet (SIM), (TTF)2[Co(pdms)2] (TTF=tetrathiafulvalene and H2pdms=1,2‐bis(methanesulfonamido)benzene), was electrochemically synthesised and investigated structurally, physically, and theoretically. The similar oxidation potentials of neutral TTF and the molecular precursor [HNEt3]2[M(pdms)2] (M=Co, Zn) allow for multiple charge transfers (CTs) between the SIM donor [M(pdms)2]n? and the TTF.+ acceptor, as well as an intradonor CT from the pdms ligand to Co ion upon electrocrystallisation. Usually TTF functions as a donor, whereas in our system TTF is both a donor and an accepter because of the similar oxidation potentials. Furthermore, the [M(pdms)2]n? donor and TTF.+ acceptor are not segregated but strongly interact with each other, contrary to reported layered donor–acceptor electrical conductors. The strong intermolecular and intramolecular interactions, combined with CT, allow for relatively high electrical conductivity even down to very low temperatures. Furthermore, SIM behaviour with slow magnetic relaxation and opening of hysteresis loops was observed. (TTF)2[Co(pdms)2] ( 2‐Co ) is an excellent building block for preparing new conductive SIMs. 相似文献
993.
Motozumi Ando Masaki Hirabatake Hisateru Yasui Shoji Fukushima Nobuyuki Sugioka Tohru Hashida 《Biomedical chromatography : BMC》2020,34(3):e4776
Mitotane is a key drug for the treatment of adrenal cortical carcinoma. Due to its narrow therapeutic window, 14–20 μg/mL, monitoring its concentration is crucially important. In this study, a simplified method for measuring mitotane in plasma using gas chromatography-electron ionization-mass spectrometry (GC-EI-MS) was developed. Through deproteination and liquid–liquid extraction, mitotane and an internal standard (IS) were extracted from plasma samples. GC-EI-MS yielded retention times of 8.2 and 8.7 min, for mitotane and the IS, respectively, with a total run time of 12 min. Selectivity and intra-/inter-batch accuracy and precision analyses provided a lower limit of quantification of 0.25 μg/mL, and a calibration curve between 0.25 and 40 μg/mL had good linearity (coefficient of determination = 0.992). The matrix effect factor and percent recovery of the method had good precision. Additionally, long-term sample stability was observed below 4°C. In a clinical setting, mitotane levels in plasma from an adrenal cortical carcinoma patient were within calibration range. Therefore, this simplified method can be applied to routine therapeutic drug monitoring of mitotane, which may contribute to improved treatment of adrenal cortical carcinoma. 相似文献
994.
Abstract A homogeneously aligned nematic liquid crystal cell with a hole-patterned electrode and with an indium-tin oxide (ITO-) coated counter-electrode has been prepared. A non-uniform electric field can be produced by the asymmetrical electrode structure. The liquid crystal director can be reoriented by applying a voltage across the electrodes, and this produces an axially symmetrical profile of the refractive index. This liquid crystal cell is expected to have a lens effect and so its optical properties have been investigated. The profile of the output light intensity was measured by using a detecting system with an optical fibre. Some relationships between the lens properties, the diameter of the hole and the thickness of the liquid crystal layer have been examined. The liquid crystal cell becomes a convex (converging) lens with a relatively low voltage. A focal length of several millimetres can be obtained by applying voltages of 3-4 V. As the applied voltage increases, the focal length becomes longer, and the cell changes to a concave (diverging) lens when a high voltage is applied (? 20 V). These properties are discussed from the viewpoint of the director orientation effects resulting from the non-uniform electric fields in the cell. 相似文献
995.
Abstract α-Cyclodextrin mainly underwent monoiodo substitution on treatment with N-iodosuccinimide and triphenylphosphine in DMF, giving 6-monodeoxy-6-monoiodo-α-cyclodextrin. A small amount of 6,6′-dideoxy-6,6′-diiodo-α-cyclodextrin was also obtained as a by-product. The structures of these compounds were elucidated from their elemental analyses and 13C NMR spectra. 相似文献
996.
Makoto Kiso Hideki Katagiri Hiroyasu Furui Keiko Ando Hideharu Ishida Akira Hasegawa 《Journal of carbohydrate chemistry》2013,32(2):163-174
Abstract O-(6-O-Benzoyl-β-d-galactopyranosyl)-(1→4)- and O-(2, 3, 4-tri-O-acetyl-β-d-galactopyranosyl)-(1→4)-2, 3, 6-tri-O-benzyl-N-benzyloxycarbonyl-1, 5-dideoxy-1, 5-imino-d-glucitols (4 and 12) were each coupled with methyl (methyl 5-acetamido-4, 7, 8, 9-tetra-O-acetyl-3, 5-dideoxy-2-thio-d-glycero-d-galacto-2-nonulopyranosid)onate (5) in acetonitrile medium in the presence of dimethyl(methylthio)sulfonium triflate (DMTST) or N-iodosuccinimide/trifluoromethanesulfonic acid to give the corresponding α-sialyl-(2 → 3)- and α-sialyl-(2 → 6)-glycosides (6 and 13α), which were converted to novel ganglioside GM3-related trisaccharides (9 and 15) containing N-methyl-1-deoxynojirimycin. 相似文献
997.
Yusuke Koito Kazuhiko Yamada Shinji Ando 《Journal of inclusion phenomena and macrocyclic chemistry》2013,76(1-2):143-150
An inclusion complex (IC) composed of a hydrofluoroether (HFE) guest and a β-cyclodextrin (β-CD) host was newly prepared, and the crystalline structure and the thermal stability of the IC were examined using several analytical methods, including wide-angle X-ray diffraction (WAXD), solid-state NMR, thermogravimetric analysis (TGA), TG–mass spectrometry (TG–MS), and quantum chemical calculation. The WAXD patterns and elemental analysis identified that the IC of an HFE/β-CD form of a channel-type structure, in which one HFE molecule is included in a common cavity of two β-CD molecules. TGA and TG–MS analysis indicated that the HFE molecules included in β-CD are hardly evaporated or degraded up to the decomposition temperature of the β-CD host. Solid-state 13C NMR indicated that the β-CD ring structure was deformed by including an HFE molecule in it, and that the 19F NMR signals of the HFE guest were significantly shifted to higher frequencies by the inclusion due to the dielectric media effect in the cavity of β-CD. Moreover, the 19F NMR signals of HFE included in IC were further shifted after annealing at 150 °C, which reflected structural changes in HFE/β-CD IC caused at elevated temperatures. The WAXD patterns also confirmed that the packing structure along the crystalline b-direction of HFE/β-CDs, which penetrates the cavities of β-CDs, was compressed by annealing and transformed to a more stable structure. 相似文献
998.
999.
Toshiaki Yamaguchi Hironori Suwaki Koichi Kikuta Shin-ichi Hirano 《Solid State Communications》2005,133(2):71-75
We fabricated the ordered Sr2FeMoO6 (SFMO) thin film with a double perovskite structure using the chemical solution deposition (CSD) method. The highly c-axis oriented SFMO thin film with a high degree of Fe/Mo ordering was successfully synthesized on an MgO (001) substrate by optimizing processing conditions. The precise preparation process control of the SFMO precursor solution leads to a typical magnetoresistance effect in a low magnetic field at room temperature. 相似文献
1000.
Kamada K. Hasegawa D. Shimizu K. Ando R. Masuzaki M. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1999,27(6):1609-1610
Two-stage autoacceleration was experimentally realized by passing an annular electron beam through a two-stage passive cavity structure. The kinetic energies of the last quarter part in the beam pulse were increased. Possibility of compression of an intense beam using multistage autoacceleration is discussed 相似文献