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991.
Kurihara Momo Yasutaka Tetsuo Aono Tatsuo Ashikawa Nobuo Ebina Hiroyuki Iijima Takeshi Ishimaru Kei Kanai Ramon Karube Zin’ichi Konnai Yae Kubota Tomijiro Maehara Yuji Maeyama Takeshi Okizawa Yusuke Ota Hiroaki Otosaka Shigeyoshi Sakaguchi Aya Tagomori Hisaya Taniguchi Keisuke Tomita Masatoshi Tsukada Hirofumi Hayashi Seiji Lee Sangyoon Miyazu Susumu Shin Moono Nakanishi Takahiro Nishikiori Tatsuhiro Onda Yuichi Shinano Takuro Tsuji Hideki 《Journal of Radioanalytical and Nuclear Chemistry》2019,322(2):477-485
Journal of Radioanalytical and Nuclear Chemistry - We assessed the repeatability and reproducibility of methods for determining low dissolved radiocesium concentrations in freshwater in Fukushima.... 相似文献
992.
Journal of Radioanalytical and Nuclear Chemistry - Sediment wastes generated from nuclear facilities often contain uranium and iron. From the viewpoint of reduction of environmental impact,... 相似文献
993.
Toshiaki Mori Yusuke Yoshigoe Yoichiro Kuninobu 《Angewandte Chemie (International ed. in English)》2019,58(41):14457-14461
Multicolor emissive materials consisting of a single luminophore, a Lewis acid, and their complex were developed. The emission colors can be tuned by changing the concentration of the solution and the ratio of mixed solvents. Various emission colors in the solid state were observed when the complexes were added to polymers in different amounts. The color change is due to equilibrium disruption between the single luminophore, the Lewis acid, and the complex thereof. White emission was observed by appropriately controlling the equilibrium by changing the amount of the complex in the polymer. 相似文献
994.
Yusuke Isaka Yudai Kawase Yasutaka Kuwahara Kohsuke Mori Hiromi Yamashita 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(16):5456-5460
Much effort has been devoted to photocatalytic production of hydrogen peroxide (H2O2) as an alternative to fossil fuels. From an economic point of view, reductive synthesis of H2O2 from O2 coupled with the oxidative synthesis of value‐added products is particularly interesting. We herein report application of MIL‐125‐NH2, a photoactive metal–organic framework (MOF), to a benzylalcohol/water two‐phase system that realized photocatalytic production and spontaneous separation of H2O2 and benzaldehyde. Hydrophobization of the MOF enabled its separation from the aqueous phase. This resulted in enhanced photocatalytic efficiency and enabled application of various aqueous solutions including extremely low pH solution which is favorable for H2O2 production but fatal to MOF structure. In addition, a highly concentrated H2O2 solution was obtained by simply reducing the volume of the aqueous phase. 相似文献
995.
Yusuke Imamura Shun Yoshioka Masanori Nagatomo Masayuki Inoue 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(35):12287-12291
1‐Hydroxytaxinine ( 1 ) is a cytotoxic taxane diterpenoid. Its central eight‐membered B‐ring possesses four oxygen‐functionalized centers (C1, C2, C9, and C10) and two quaternary carbon centers (C8 and C15), and is fused with six‐membered A‐ and C‐rings. The densely functionalized and intricately fused structure of 1 makes it a highly challenging synthetic target. Reported here is an efficient radical‐based strategy for assembling 1 from A‐ and C‐ring fragments. The A‐ring bearing an α‐alkoxyacyl telluride moiety underwent intermolecular coupling with the C‐ring fragment by a Et3B/O2‐promoted decarbonylative radical formation. After construction of the C8‐quaternary stereocenter, a pinacol coupling reaction using a low‐valent titanium reagent formed the B‐ring with stereoselective installation of the C1,C2‐diol. Subsequent manipulations at the A‐ and C‐rings furnished 1 in 26 total steps. 相似文献
996.
Kosaku Tanaka Yusuke Honma Chihiro Yamaguchi Lina Aoki Minami Saito Momoko Suzuki Kazuhiro Arahata Kaoru Kinoshita Kiyotaka Koyama Kenichi Kobayashi Hiroshi Kogen 《Tetrahedron》2019,75(8):1085-1097
The relative and absolute configurations of L-755,807 were established through total synthesis. All four possible stereoisomers were prepared via a convergent synthetic strategy, including a novel diastereoselective Darzens reaction of an α-alkoxy aldehyde with di-tert-butyl bromomalonate, an E-selective Horner–Wadsworth–Emmons reaction, and late-stage coupling of the ring and side-chain segments. Additionally, biological evaluation of the synthesized compounds revealed their potent inhibitory activities (IC50?=?5–21?μM) against amyloid-β aggregation for the treatment of Alzheimer's disease. 相似文献
997.
Takuya Morozumi Hideaki Okane Hiroki Sakamoto Yusuke Shimizu Kenta Takagi Hiroyuki Umeeda 《中国物理C(英文版)》2018,(2)
We discuss a supersymmetric model with discrete flavor symmetry A_4×Z_3. The additional scalar fields which contribute masses of leptons in the Yukawa terms are introduced in this model. We analyze their scalar potential and find that they have various vacuum structures. We show the relations among 24 different vacua and classify them into two types. We derive expressions of the lepton mixing angles, Dirac CP violating phase and Majorana phases for the two types. The model parameters which are allowed by the experimental data of the lepton mixing angles are different for each type. We also study the constraints on the model parameters which are related to Majorana phases. The different allowed regions of the model parameters for the two types are shown numerically for a given region of two combinations of the CP violating phases. 相似文献
998.
We consider a Fermi gas with two components of different masses, with the s-wave two-body interaction tuned to unitarity. In the range of mass ratio 8.62相似文献
999.
We report 31P and 139La NMR studies of (La0.87Ca0.13)FePO, which is a family member of the recently discovered superconductor LaFeAs(O1-xFx). In the normal state, Knight shift and nuclear spin-lattice relaxation rate divided by T (1/T1T) show that a Fermi-liquid state with moderate ferromagnetic fluctuations emerges below 30 K. From 1/T1T of 31P and 139La, a quasi-two- dimensional electronic structure is suggested, in which the FeP layer is more conductive than the LaO layer. In the superconducting (SC) state, although a clear Meissner signal was observed, 1/T1T increases below Tc, in contrast to a decrease of 1/T1T due to the opening of a SC gap, suggesting that novel low-energy spin dynamics develop in the SC state. 相似文献
1000.
Yusuke Takara Koji FujiwaraYoshiyuki Ishihara Toshiyuki Todaka 《Journal of magnetism and magnetic materials》2008
A single sheet tester (SST) for audio frequency of 400 Hz–10 kHz was made experimentally and the magnetizing winding can get the nearly uniform distribution of flux density of a specimen in the longitudinal direction at the frequency up to 10 kHz. The flux densities at various positions of strips measured by the Epstein method were detected by search coils wound on strips at 400 Hz and 1.0 T. They have large discrepancy. However, the magnetic properties obtained from both methods have a little discrepancy. Although the uniformity of flux distribution in the Epstein frame is not sufficient, the average is fairly effective because the magnetic properties can be assumed to be locally linear within the small deviation of flux density. 相似文献