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排序方式: 共有244条查询结果,搜索用时 15 毫秒
121.
The modification of protein by arginine catalyzed by arginyltransferases (ATE1) described by the Kashina group in this issue shows that arginylation of protein occurs widely in biology and is being recognized as a key regulatory reaction such as phosphorylation of proteins (Wang et?al., 2011). 相似文献
122.
Kohmoto S Tsuyuki R Hara Y Kaji A Takahashi M Kishikawa K 《Chemical communications (Cambridge, England)》2011,47(32):9158-9160
Amphiphilic anthracene derivatives showed solvent-polarity-dependent fluorescence. Monomer emission and aggregation-induced emission (AIE) were observed in polar and non-polar organic solvents, respectively. AIE became predominant in aqueous solution in the case of hexafluorophosphate as a counter anion. 相似文献
123.
Kubozono Y Mitamura H Lee X He X Yamanari Y Takahashi Y Suzuki Y Kaji Y Eguchi R Akaike K Kambe T Okamoto H Fujiwara A Kato T Kosugi T Aoki H 《Physical chemistry chemical physics : PCCP》2011,13(37):16476-16493
New carbon-based superconductors are synthesized by intercalating metal atoms into the solid-phase hydrocarbons picene and coronene. The highest reported superconducting transition temperature, T(c), of a hydrocarbon superconductor is 18 K for K(3)picene. The physics and chemistry of the hydrocarbon superconductors are extensively described for A(x)picene (A: alkali and alkali earth-metal atoms) for x = 0-5. The theoretical picture of their electronic structure is also reviewed. Future prospects for hydrocarbon superconductors are discussed from the viewpoint of combining electronics with condensed-matter physics: modification of the physical properties of hydrocarbon solids is explored by building them into a field-effect transistor. The features of other carbon-based superconductors are compared to clarify the nature of hydrocarbon superconductors. 相似文献
124.
Abe K Hayato Y Iida T Ikeda M Iyogi K Kameda J Koshio Y Kozuma Y Miura M Moriyama S Nakahata M Nakayama S Obayashi Y Sekiya H Shiozawa M Suzuki Y Takeda A Takenaga Y Takeuchi Y Ueno K Ueshima K Watanabe H Yamada S Yokozawa T Ishihara C Kaji H Lee KP Kajita T Kaneyuki K McLachlan T Okumura K Shimizu Y Tanimoto N Martens K Vagins MR Labarga L Magro LM Dufour F Kearns E Litos M Raaf JL Stone JL Sulak LR Goldhaber M Bays K Kropp WR Mine S Regis C Smy MB Sobel HW Ganezer KS Hill J Keig WE Jang JS 《Physical review letters》2011,107(24):241801
We present a search for differences in the oscillations of antineutrinos and neutrinos in the Super-Kamiokande-I, -II, and -III atmospheric neutrino sample. Under a two-flavor disappearance model with separate mixing parameters between neutrinos and antineutrinos, we find no evidence for a difference in oscillation parameters. Best-fit antineutrino mixing is found to be at (Δm2,sin2 2θ)=(2.0×10(-3) eV2, 1.0) and is consistent with the overall Super-K measurement. 相似文献
125.
Tatsuya Fukushima Hirotaka Ishibashi Daichi Suemasa Ryosuke Nakamura Masanobu Yomogida Takuya Isono Toshifumi Satoh Hironori Kaji 《Journal of Polymer Science.Polymer Physics》2019,57(5):266-271
In this study, cyclic poly(3‐hexylthiophene‐2,5‐diyl) (c‐P3HT) with a controlled Mn was synthesized by the intramolecular cyclization of α‐bromo‐ω‐ethynyl‐functionalized P3HT via the Sonogashira coupling reaction. The effect of the cyclic structure, which does not have terminal groups of polymers, on the photoelectric conversion characteristics was investigated in comparison to linear P3HT (l‐P3HT). c‐P3HT was successfully synthesized with Mn ≈ 17,000, dispersity ≈ 1.2, and regioregularity ≈ 99%. The hole mobility was determined to be 5.1 × 10?4 cm2 V?1 s?1 by time‐of‐flight (TOF) experiment. This was comparable to that of l‐P3HT of 5.6 × 10?4 cm2 V?1 s?1. Organic solar cell systems were fabricated with each polymer by blending them with [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM). The l‐P3HT:PC71BM system showed a dispersive TOF photocurrent profile for electron transport, whereas a nondispersive profile was observed for c‐P3HT:PC71BM. In addition, an amount of collected electrons in c‐P3HT:PC71BM was greater than that in l‐P3HT:PC71BM for TOF experiments. The photoelectric conversion characteristics were improved by using c‐P3HT rather than l‐P3HT (power conversion efficiency [PCE] = 4.05% vs 3.23%), reflecting the nondispersive transport and the improvement of electron collection. PCEs will be much improved by applying this cyclic concept to highly‐efficient OSC polymers. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 266–271 相似文献
126.
Asymmetric Synthesis of an Amino Acid Derivative from Achiral Aroyl Acrylamide by Reversible Michael Addition and Preferential Crystallization
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Yuki Kaji Naohiro Uemura Prof. Yoshio Kasashima Hiroki Ishikawa Prof. Yasushi Yoshida Prof. Takashi Mino Prof. Masami Sakamoto 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(46):16429-16432
Single‐handed α‐amino acid derivatives were generated from achiral precursors without an external chiral source. Conjugate addition of phenethylamine to an achiral aroyl acrylamide under homogeneous conditions gave the α‐amino amides in quantitative yields, which crystallized as a conglomerate of a P21 crystal system. Dynamic preferential crystallization or attrition‐enhanced deracemization resulted in the formation of enantiomorphic crystals of 99 % ee. 相似文献
127.
Hiroshi Nakano Seiji Kosemura Toshisada Suzuki Ryota Kaji Katsutoshi Hirose 《Tetrahedron letters》2010,51(1):49-53
Oryzamutaic acids B-G (1-6), structurally unique nitrogen-containing heterocyclic alkaloids, were isolated from the endosperm (polished rice) of an Oryza sativa mutant. The structures and relative stereochemistries of 1-6 were elucidated on the basis of spectroscopic and single-crystal X-ray diffraction analyses. 相似文献
128.
Kaji H Kawashima T Nishizawa M 《Langmuir : the ACS journal of surfaces and colloids》2006,22(25):10784-10787
We describe herein a method for controlling the pattern of permissible cell migration and proliferation on a substrate in time and space. Using this method, a confluent monolayer of cells that is confined within a defined region is released into a neighboring region. Incorporated into the method is an electrochemical technique that uses a scanning microelectrode to draw regions on the surface of the system that thereafter can support cell migration and growth. The supporting glass substrate is patterned with regions of 2-methacryloyloxyethyl phosphorylcholine (MPC) polymer that are not affected by the electrochemical treatment and also robustly resist cellular overgrowth as well as regions that can be individually switched when electrochemically treated from cell repellent to cell adhering. It is therefore possible to strictly define the areas into which cells can migrate. We found that HeLa cells migrate more rapidly as the width of cell-adhering lanes increases until a width of ca. 50 microm is reached, at which point the migration rate is roughly constant. We also designed a drug assay using our cell migration technique. The technique allows for cell migration only into defined region(s) and therefore may become an important tool for evaluating the biological activity of potential drugs because drug activity and cell motility often directly correlate. 相似文献
129.
We consider the problem how far from being homotopy commutative is a loop space having the homotopy type of the p-completion of a product of finite numbers of spheres. We determine the homotopy nilpotency of those loop spaces as an answer
to this problem. 相似文献
130.