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341.
342.
Dr. Ryuta Ishikawa Shuya Ueno Shoei Nifuku Dr. Yoji Horii Dr. Hiroaki Iguchi Prof. Yuji Miyazaki Prof. Motohiro Nakano Prof. Shinya Hayami Dr. Shohei Kumagai Dr. Keiichi Katoh Prof. Zhao-Yang Li Prof. Masahiro Yamashita Prof. Satoshi Kawata 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(6):1278-1285
The reaction of Fe(OAc)2 and Hbpypz with neutral TCNQ results in the formation of [Fe2(bpypz)2(TCNQ)2](TCNQ)2 ( 1 ), in which Hbpypz=3,5-bis(2-pyridyl)pyrazole and TCNQ=7,7′,8,8′-tetracyano-p-quinodimethane. Crystal packing of 1 with uncoordinated TCNQ and π–π stacking of bpypz− ligands produces an extended two-dimensional supramolecular coordination assembly. Temperature dependence of the dc magnetic susceptibility and heat capacity measurements indicate that 1 undergoes an abrupt spin crossover (SCO) with thermal spin transition temperatures of 339 and 337 K for the heating and cooling modes, respectively, resulting in a thermal hysteresis of 2 K. Remarkably, the temperature dependence of dc electrical transport exhibits a transition that coincides with thermal SCO, demonstrating the thermally induced magnetic and electrical bistability of 1 , strongly correlating magnetism with electrical conductivity. This outstanding feature leads to thermally induced simultaneous switching of magnetism and electrical conductivity and a magnetoresistance effect. 相似文献
343.
Various diacyl sulfides were synthesized by reaction of acyl chlorides with LiAlHSH. Reaction of glutaryl chloride with LiAlHSH afforded glutaric thioanhydride. © 2003 Wiley Periodicals, Inc. Heteroatom Chem 14:633–635, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.10217 相似文献
344.
Yoji Ikeda Yasuhiko Yoshida Kenji Ishihara Hiroshi Hamana Tadashi Narita Tokio Hagiwara 《Macromolecular rapid communications》1996,17(10):713-721
Novel copolymers consisting of 3,3,3-trifluoro-1,2-epoxypropane (TFEP) and N-phenylmaleimide (PMI) units were prepared by the copolymerization of TFEP with PMI initiated with an organozinc compound. Using [Zn(OCH3)2 · (C2H5ZnOCH3)4] as an initiator, the copolymer chains consisted mainly of TFEP-TFEP sequences. The TFEP-PMI sequence content in the copolymer chains was small. On the other hand, using (C2H5ZnOCH3)4 as an initiator, only low molecular weight copolymers were formed. Those copolymers were suggested to have block structure, poly(TFEP)-block-poly(PMI), by the 19F NMR analysis. The copolymers showed higher thermostability than poly-(TFEP). 相似文献
345.
346.
Takafumi Aizawa 《Molecules (Basel, Switzerland)》2020,25(24)
It was verified that deep learning can be used in creating multilayer membranes with multiple porosities using the CO2-assisted polymer compression (CAPC) method. To perform training while reducing the number of experimental data as much as possible, the experimental data of the compression behavior of two layers were expanded to three layers for training, but sufficient accuracy could not be obtained. However, the accuracy was dramatically improved by adding the experimental data of the three layers. The possibility of only simulating process results without the necessity for a model is a merit unique to deep learning. Overall, in this study, the results show that by devising learning data, deep learning is extremely effective in designing multilayer membranes using the CAPC method. 相似文献
347.
Two oxidized forms of low-density lipoprotein (LDL), oxidized (Ox-LDL) and minimally modified (MM-LDL), and the immune complexes (LDL-ICs) that they form with their corresponding antibodies, play a major role in the pathogenesis of atherosclerosis. Recently, we reported that the heptapeptide KP6 (Lys-Trp-Tyr-Lys-Asp-Gly-Asp) coupled through its ε-amino group present on the N-terminal Lys to fluorescein isothiocyanate (FITC)— (FITC)KP6— binds specifically to Ox-LDL and MM-LDL, but not to native LDL. Here, to develop a novel method for measuring the levels of oxidatively modified LDL in blood, using (FITC)KP6, we analyzed the latter’s binding with MM-LDL-IC and Ox-LDL-IC. Polyacrylamide gel electrophoresis analysis revealed that (FITC)KP6 could efficiently and specifically bind to polyethylene glycol (PEG)-precipitated MM-LDL-IC and Ox-LDL-IC in a dose-dependent manner with high sensitivity in plasma and serum. Our results indicate that the above method for measuring the levels of PEG-precipitated, oxidatively modified LDL-ICs, formed by the addition of anti-Ox-LDL antibody to blood, using (FITC)KP6, can aid the diagnosis of atherosclerosis. 相似文献
348.
In situ observation of the failure characteristics of a cast aluminum alloy has been conducted using a testing system with a high-speed camera. The failure process of the cast Al alloy was captured clearly with an high image resolution (1,024?×?1,024 pixels) at a high frame rate (20,000/s), where the specimen surface for observation was dyed dark using a black oil-based ink. A dark curtain was set behind the test specimen as background. Strong lighting of about 10 klx was used, which was applied to the dark specimen surface for clarification of material failure. The aim of this approach was to detect the failure characteristics or failure objects with bright zone. Using this system, both debris particles flying from the fracture sample and dislocation-like movements were detected. These were observable as tiny bright dots. The flying debris particles of about 35 μm in diameter consisted mainly of Si- and Fe-based eutectic structures. The flying speed of the debris particles was about 1,800 mm/s and their flight distance from the specimen was about 100 mm. The velocity of the dislocation-like movements was found to be less than 1,000 mm/s, and this motion was seen repeatedly before and after sample failure occurred. 相似文献
349.
Dr. Cédric Tassel Yoshinori Kuno Yoshihiro Goto Dr. Takafumi Yamamoto Dr. Craig M. Brown Dr. James Hester Dr. Koji Fujita Dr. Masanobu Higashi Prof. Ryu Abe Prof. Katsuhisa Tanaka Dr. Yoji Kobayashi Prof. Hiroshi Kageyama 《Angewandte Chemie (International ed. in English)》2015,54(2):516-521
The synthesis, structure, and magnetic properties of a polar and magnetic oxynitride MnTaO2N are reported. High‐pressure synthesis at 6 GPa and 1400 °C allows for the stabilization of a high‐density structure containing middle‐to‐late transition metals. Synchrotron X‐ray and neutron diffraction studies revealed that MnTaO2N adopts the LiNbO3‐type structure, with a random distribution of O2? and N3? anions. MnTaO2N with an “orbital‐inactive” Mn2+ ion (d5; S=5/2) exhibits a nontrivial helical spin order at 25 K with a propagation vector of [0,0,δ] (δ≈0.3), which is different from the conventional G‐type order observed in other orbital‐inactive perovskite oxides and LiNbO3‐type oxides. This result suggests the presence of strong frustration because of the heavily tilted MnO4N2 octahedral network combined with the mixed O2?/N3? species that results in a distribution of (super)‐superexchange interactions. 相似文献
350.