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61.
The local molecular orientation in the electroclinic effect of the chiral smectic A phase in a surface-stabilised cell has been determined using a time-resolved synchrotron X-ray microbeam diffraction technique. Space- and time-resolved X-ray wide-angle halo scattering under an electric field reveals the static and dynamic intralayer molecular orientation. The molecular orientation varies spatially in accordance with the stripe texture and is dependent on the applied voltage. It has been found that the deviation of the molecular orientation from the rubbing direction depends strongly on the sample history. The relation between the apparent molecular orientation and the layer structure is discussed. 相似文献
62.
Guan-Yeow Yeap Michi Nakata Yoichi Takanishi Ken Ishikawa Hideo Takezoe 《Liquid crystals》2013,40(11):1437-1443
In order to study the difference in microscopic orientation of ferro- and antiferroelectric liquid crystalline molecules, we synthesized the partially deuteriated chiral compounds, (S)-(-)-2-methylbutyl 4-(4-(d13)-hexyloxy- and (S)-(-)-2-methylbutyl 4-(4-(d17)-octyloxy-phenyl)benzoates. Fundamental physical properties such as phase transition temperatures, spontaneous polarization and tilt angle were determined. Polarized FTIR measurements were also made to provide information on molecular structure and orientation. 相似文献
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In this paper, applying both Lyapunov function techniques and monotone iterative techniques, we establish new sufficient conditions under which the infected equilibrium of an HIV pathogenesis model with cure rate is globally asymptotically stable. By giving an explicit expression for eventual lower bound of the concentration of susceptible CD4+ T cells, we establish an affirmative partial answer to the numerical simulations investigated in the recent paper [Liu, Wang, Hu and Ma, Global stability of an HIV pathogenesis model with cure rate, Nonlinear Analysis RWA (2011) 12 : 2947–2961]. Our monotone iterative techniques are applicable for the small and large growth rate in logistic functions for the proliferation rate of healthy and infected CD4+ T cells. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
66.
Co–Pd bimetallic alloy nanoparticle catalysts were prepared from CoCl2, Pd(OAc)2 and several capping agents with Li(C2H5)3BH. The nanoparticle catalysts were applied to the aerobic oxidation of a variety of alcohols in water to give the corresponding carbonyl products. The catalyst was magnetically recovered and reused for further oxidation. The nanoparticle catalysts were characterized with TEM, ICP, and XPS analyses. 相似文献
67.
Akter Sharmin Tanabe Tomoki Maejima Satoshi Kawauchi Satoko Sato Shunichi Hinoki Akinari Aosasa Suefumi Yamamoto Junji Nishidate Izumi 《Optical Review》2016,23(2):354-359
Optical Review - To quantify the changes in optical properties of in vivo rat liver tissue, we applied diffuse reflectance spectroscopy (DRS) system using single-reflectance fiber probe during... 相似文献
68.
Shirai T Ikegami M Fujimoto S Souda H Tanabe M Tongu H Noda A Noda K Fujimoto T Iwata S Shibuya S Smirnov A Meshkov I Fadil H Grieser M 《Physical review letters》2007,98(20):204801
The ordering of protons has been observed at a new storage ring, S-LSR, at Kyoto University. Abrupt jumps in the momentum spread and the Schottky noise power were observed for protons for the first time at a particle number of approximately 2000, upon applying electron cooling with electron currents of 25, 50, and 100 mA. The transition temperature was 0.17 and 1 meV in the longitudinal and transverse directions, respectively. The transverse temperature of the proton beam was much below that of electrons at the transition, which played an essential role in the ordering of protons. 相似文献
69.
Serine‐Selective Aerobic Cleavage of Peptides and a Protein Using a Water‐Soluble Copper–Organoradical Conjugate 下载免费PDF全文
Yohei Seki Dr. Kana Tanabe Dr. Daisuke Sasaki Dr. Youhei Sohma Dr. Kounosuke Oisaki Prof. Dr. Motomu Kanai 《Angewandte Chemie (International ed. in English)》2014,53(25):6501-6505
The site‐specific cleavage of peptide bonds is an important chemical modification of biologically relevant macromolecules. The reaction is not only used for routine structural determination of peptides, but is also a potential artificial modulator of protein function. Realizing the substrate scope beyond the conventional chemical or enzymatic cleavage of peptide bonds is, however, a formidable challenge. Here we report a serine‐selective peptide‐cleavage protocol that proceeds at room temperature and near neutral pH value, through mild aerobic oxidation promoted by a water‐soluble copper–organoradical conjugate. The method is applicable to the site‐selective cleavage of polypeptides that possess various functional groups. Peptides comprising D ‐amino acids or sensitive disulfide pairs are competent substrates. The system is extendable to the site‐selective cleavage of a native protein, ubiquitin, which comprises more than 70 amino acid residues. 相似文献
70.
Dr. Yoshikazu Ito Dr. Yoichi Tanabe Dr. H.‐J. Qiu Dr. Katsuaki Sugawara Dr. Satoshi Heguri Dr. Ngoc Han Tu Dr. Khuong Kim Huynh Dr. Takeshi Fujita Prof. Takashi Takahashi Prof. Katsumi Tanigaki Prof. Mingwei Chen 《Angewandte Chemie (International ed. in English)》2014,53(19):4822-4826
We report three‐dimensional (3D) nanoporous graphene with preserved 2D electronic properties, tunable pore sizes, and high electron mobility for electronic applications. The complex 3D network comprised of interconnected graphene retains a 2D coherent electron system of massless Dirac fermions. The transport properties of the nanoporous graphene show a semiconducting behavior and strong pore‐size dependence, together with unique angular independence. The free‐standing, large‐scale nanoporous graphene with 2D electronic properties and high electron mobility holds great promise for practical applications in 3D electronic devices. 相似文献