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751.
Nakajima Y Shiraishi Y Tsuchimoto T Ozawa F 《Chemical communications (Cambridge, England)》2011,47(22):6332-6334
Cu(I) complexes bearing BPEP as a PNP-pincer type phosphaalkene ligand undergo effective bonding interactions with SbF(6)(-) and PF(6)(-) as non-coordinating anions to give [Cu(SbF(6))(BPEP)] and [Cu(2)(BPEP)(2)(μ-PF(6))](+), respectively [BPEP = 2,6-bis(1-phenyl-2-phosphaethenyl)pyridine]. NMR and theoretical studies indicate a reduced anionic charge of the μ-PF(6) ligand, which is induced by the strong π-accepting ability of BPEP. 相似文献
752.
Stigers DJ Watts ZI Hennessy JE Kim HK Martini R Taylor MC Ozawa K Keillor JW Dixon NE Easton CJ 《Chemical communications (Cambridge, England)》2011,47(6):1839-1841
3-Chloro-Abu and 4-chloro-Nva are biosynthetically incorporated into E. coli peptidyl-Pro cis-trans isomerase B, as substitutes for Val and Leu, respectively. The extent of incorporation is up to ~90%, and substituted protein is catalytically active. By contrast, 4-chloro-Val is not an effective replacement for Ile. 相似文献
753.
754.
We examined CH/π hydrogen bonds in protein/ligand complexes involving at least one proline residue using the ab initio fragment molecular orbital (FMO) method and the program CHPI. FMO calculations were carried out at the Hartree–Fock (HF)/6‐31G*, HF/6‐31G**, second‐order Møller–Plesset perturbation (MP2)/6‐31G*, and MP2/6‐31G** levels for three Src homology 3 (SH3) domains and five proline‐recognition domains (PRDs) complexed with their corresponding ligand peptides. PRDs use a conserved set of aromatic residues to recognize proline‐rich sequences of specific ligands. Many CH/π hydrogen bonds were identified in these complexes. CH/π hydrogen bonds occurred, in particular, in the central part of the proline‐rich motifs. Our results suggest that CH/π hydrogen bonds are important in the recognition of SH3 and PRDs by their ligand peptides and play a vital role in the signal transduction system. Combined use of the FMO method and CHPI analysis is a valuable tool for the study of protein/protein and protein/ligand interactions and may be useful in rational drug design. © 2011 Wiley Periodicals, Inc. J Comput Chem 2011 相似文献
755.
Ishizu K Amir I Okamoto N Uchida S Ozawa M Chen H 《Journal of colloid and interface science》2011,353(1):69-75
Narrow disperse core-brush polymer nanoparticles (BP) were synthesized by grafting from photo-induced atom transfer radical polymerization (ATRP) of 2-hydroxyethyl methacrylate (HEMA) from N,N-diethyldithiocarbamate (DC) groups of core-shell particle surface. We constructed colloidal crystals of these particles by depositing on glass substrate. By variation of the particle size, the brilliant color could be varied throughout the visible spectrum. We locked also permanently such colloidal crystals by cross-linking of poly(2-hydroxyethyl methacrylate) (PHEMA) brush phases with glutaraldehyde. The peak wavelength (λ(max)) in the reflection spectra agreed well with the bandgap position for light incident on the (1 1 1) face of face-centered cubic (fcc) lattice according to Bragg's law. 相似文献
756.
Kaneko S Ito T Hirabayashi Y Ozawa T Okuda T Motoizumi Y Hirai K Naganuma Y Soga M Yoshimoto M Suzuki K 《Talanta》2011,84(2):579-582
Metal oxide nanoparticles prepared by pulsed laser deposition (PLD) were applied to nonenzymatic glucose detection. NiO nanoparticles with size of 3 nm were deposited on glassy carbon (GC) and silicon substrates at room temperature in an oxygen atmosphere. Transmission electron microscope (TEM) image showed nanoparticles with the size of 3 nm uniformly scattered on the Si(0 0 1) substrate. Unlike co-sputtering nanoparticle and carbon simultaneously, the PLD method can easily control the surface coverage of nanoparticles on the surface of substrate by deposition time. Cyclic voltammetry was performed on the samples deposited on the GC substrates for electrochemical detection of glucose. The differences between peak currents with and without glucose was used to optimize the coverage of nanoparticles on carbon electrode. The results indicated that optimal coverage of nanoparticles on carbon electrode. 相似文献
757.
758.
Ma YuGang Fang DeQing Sun XiaoYan Zhou Pei Cai XiangZhou Chen JinGen Guo Wei Tian WenDong Wang HongWei Zhang GuoQiang Cao XiGuang Fu Yao Hu ZhengGuo Wang JianSong Wang Meng Togano Y. Aoi N. Baba H. Honda T. Okada K. Hara Y. Ieki K. Ishibashi Y. Itou Y. Iwasa N. Kanno S. Kawabata T. Kimura H. Kondo Y. Kurita K. Kurokawa M. Moriguchi T. Murakami H. Oishi H. Ota S. Ozawa A. Sakurai H. Shimoura S. Shioda R. Takeshita E. Takeuchi S. Yamada K. Yamada Y. Yasuda Y. Yoneda K. Motobayashi T. 《中国科学:物理学 力学 天文学(英文版)》2011,54(1):18-23
Two-proton relative momentum distributions from the break-up channels 23Al→p+p+21Na and 22Mg→p+p+20Ne at an energy of 60–70 A MeV have been measured together with two-proton opening angles at the projectile fragment separator beamline (RIPS) in the RIKEN Ring Cyclotron Facility. The results demonstrate the existence of diproton emission component from single-step 2He for highly excited 23Al and 22Mg. 相似文献
759.
Hongyang Zhao Hideo Kimura Zhenxiang Cheng Xiaolin Wang Kiyoshi Ozawa Takashi Nishida 《固体物理学:研究快报》2010,4(11):314-316
Single phase Bi2FeMnO6 films on (100) SrTiO3 substrate were fabricated using a pulsed laser deposition method through optimization of the preparation conditions. The magnetic moment is 0.30μB at 5 K in the magnetic field of 1 T, indicating that B site cations of Fe and Mn are disordered in the sample. The zero‐field‐cooling (ZFC) and field‐cooling (FC) magnetization curves measured from 2 K to 400 K coincide at 360 K. This is consistent with the observation that hysteresis disappears at 360 K, revealing the antiferromagnetic transition at this temperature. A spin‐glass‐like behaviour was observed at low temperature (~100 K) with a cusp of 25 K. Mn shows multiple valence states in the film. It is possibly because Mn2+ and Mn4+ could decrease the Jahn–Teller effect from Mn3+ in the film which results in less lattice distortion. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
760.
Yoshiaki Kokubo Itsuki Igarashi Kenichi Nakao Wataru Hachiya Shinichi Kugimiya Tomohiro Ozawa Hideki Masuda Yuji Kajita 《Molecules (Basel, Switzerland)》2022,27(18)
The reactions of newly designed lithiated triamidoamines Li3LR (R = iPr, Pen, and Cy2) with VCl3(THF)3 under N2 yielded dinitrogen–divanadium complexes with a μ-N2 between vanadium atoms [{V(LR)}2(μ-N2)] (R = iPr (1) and Pen (2)) for the former two, while not dinitrogen–divanadium complexes but a mononuclear vanadium complex with a vacant site, [V(LCy2)] (R = Cy2 (3)), were obtained for the third ligand. The V–NN2 and N–N distances were 1.7655(18) and 1.219(4) Å for 1 and 1.7935(14) and 1.226(3) Å for 2, respectively. The ν(14N–14N) stretching vibrations of 1 and 2, as measured using resonance Raman spectroscopy, were detected at 1436 and 1412 cm–1, respectively. Complex 3 reacted with potassium metal in the presence of 18-crown-6-ether under N2 to give a hetero-dinuclear vanadium complex with μ-N2 between vanadium and potassium, [VK(LCy2)(μ-N2)(18-crown-6)] (4). The N–N distance and ν(14N–14N) stretching for 4 were 1.152(3) Å and 1818 cm−1, respectively, suggesting that 4 is more activated than complexes 1 and 2. The complexes 1, 2, 3, and 4 reacted with HOTf and K[C10H8] to give NH3 and N2H4. The yields of NH3 and N2H4 (per V atom) were 47 and 11% for 1, 38 and 16% for 2, 77 and 7% for 3, and 80 and 5% for 4, respectively, and 3 and 4, which have a ligand LCy2, showed higher reactivity than 1 and 2. 相似文献