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101.
Yamasaki Y Sagayama H Abe N Arima T Sasai K Matsuura M Hirota K Okuyama D Noda Y Tokura Y 《Physical review letters》2008,101(9):097204
The ferroelectric state in an orthorhombic perovskite RMnO3 (R=Gd0.7Tb0.3) was proved by neutron scattering studies to show the cycloidal spin state with the ab-spiral plane and the spin-helicity dependent polarization vector along the a axis, sharing the microscopic origin (inverse Dzyaloshinskii-Moriya interaction) with the more widely observed P||c state (e.g., for R=Tb and Dy) with the bc-spiral plane. The magnetic-field induced polarization flop from P||c to P||a as well known for RMnO3 is thus assigned to the orthogonal flop of the spin spiral plane from bc to ab. 相似文献
102.
Yoshihumi Kusumoto Hiroyasu Sato Kazuto Maeno Shuichi Yahiro 《Chemical physics letters》1978,53(2):388-390
The laser and fluorescence behavior was studied for the mixed dye system containing various concentrations of 3,3′-diethylthiacarbocyanine iodide and rhodamine 6G. A new way of confirming the occurrence of energy transfer is presented on the basis of the reabsorption effect. 相似文献
103.
This paper overviews ultra-high-speed optical modulators fabricated on LiNbO3 substrate, which are used in large-capacity optical transmission systems. 相似文献
104.
The noisy fluctuation of chemical reactions should profoundly affect the oscillatory dynamics of gene circuit. In this paper a prototypical genetic oscillator, repressilator, is numerically simulated to analyze effects of noise on oscillatory dynamics. The oscillation is coherent when the protein number and the rate of the DNA state alteration are within appropriate ranges, showing the phenomenon of coherence resonance. Stochastic fluctuation not only disturbs the coherent oscillation in a chaotic way but also destabilizes the stationary state to make the oscillation relatively stable. Bursting in translation, which is a source of intense stochastic fluctuation in protein numbers, suppresses the destructive effects of the finite leakage rate of protein production and thus plays a constructive role for the persistent oscillation. When multiple repressilators are coupled to each other, the cooperative interactions among repressilators enhance the coherence in oscillation but the dephasing fluctuation among multiple repressilators induces the amplitude fluctuation in the collective oscillation. 相似文献
105.
Ryosuke Matsuoka Tatsuto Yui Ryo Sasai Katsuhiko Takagi Haruo Inoue 《Molecular Crystals and Liquid Crystals》2013,570(2):333-338
Abstract Tetra-(4-sulfonatophenyl)porphyrinatotin(IV) aggregated efficiently in a clay (saponite) layer intercalated with a polyfluorinated surfactant, but no aggregation was observed in a hydrocarbon type surfactant-clay hybrid environment. Germanium(IV) porphyrins remained as monomers even in the polyfluorinated environment. 相似文献
106.
Ayesha Sultana Kazuto Sazawa Md. Saiful Islam Kazuharu Sugawara 《Analytical letters》2019,52(7):1153-1164
A novel and simple method is proposed for the determination of tetracycline by adsorptive voltammetry in a droplet using a carbon nanotube paste rotating disk electrode (CNTP-RDE). An enhanced electrochemical oxidation response of tetracycline was observed in pH 8.2 supporting electrolyte by the addition of a long-chain cationic surfactant, such as benzyldimethyltetradecylammonium chloride (zephiramine). Under the optimized experimental conditions, the calibration curve was linear across a tetracycline concentration range from 1.0?×?10?7 to 2.0?×?10?6 M. The limit of detection and sensitivity were 4.0?×?10?8 M and 0.9358?A M?1, respectively. This method was successfully employed for the determination of tetracycline in milk samples. 相似文献
107.
Kaneko Y Iyi N Bujdák J Sasai R Fujita T 《Journal of colloid and interface science》2004,269(1):22-25
Effect of layer charge density of clay on the orientation and aggregation state of a laser dye, oxazine 4, in dye/clay complexes was investigated using a series of layer-charge-controlled montmorillonites as host materials. By the combination of polarized UV-vis spectroscopy and powder X-ray diffraction methods, it was revealed that the higher layer charge caused the formation of higher-order H-aggregates with the molecular axis nearly perpendicular to the silicate layer, and that the basal spacing was mostly governed by the degree of dye aggregation. 相似文献
108.
Kazuto Inoue Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1995,33(14):2291-2296
New aromatic diamines containing phenyl-pendant thiazole units were synthesized in three steps starting from p-nitrobenzyl phenyl ketone. Novel aromatic polyamides containing phenyl-pendant thiazole units were prepared by the low-temperature solution polyconden-sation of 1,4- (or 1.3-) bis[5-(p-aminophenyl)-4-phenyl-2-thiazolyl] benzene with various aromatic dicarboxylic acid chlorides in N,N-dimethylacetamide. High molecular weight polyamides having inherent viscosities of 0.5–3.0 dL/g were obtained quantitatively. The polythiazole-amides with m-phenylene, 4,4′-oxydiphenylene, and 4,4′-sulfonyldiphenylene units were soluble in N-methyl-2-pyrrolidone, N,N-dimethylacetamide, and pyridine, and gave transparent flexible films by casting from the solutions. These organic solvent-soluble polyamides displayed prominent glass transition temperatures (Tg) between 257 and 325°C. On the other hand, the polythiazole-amides with p-phenylene and 4,4′-biphenylene units were insoluble in most organic solvents, and had no observed Tg. All the polythiazole-amides started to decompose at about 400°C with 10% weight loss being recorded at 450–525°C in air. © 1995 John Wiley & Sons, Inc. 相似文献
109.
Cheng Peng Dr. Taichi Kusakabe Shoko Kikkawa Prof. Dr. Tomoyuki Mochida Prof. Dr. Isao Azumaya Dr. Yogesh Daulat Dhage Dr. Keisuke Takahashi Prof. Dr. Hiroaki Sasai Prof. Dr. Keisuke Kato 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(3):733-737
The first example of an asymmetric cyclization–dimerization of (ortho-alkynyl phenyl) (methoxymethyl) sulfides with a palladium(II) bisoxazoline (box) catalyst has been developed. The box ligand enhances the alkynophilicity of benzothienyl palladium(II) intermediate A and thus promotes coordination of the second alkyne substrate, leading to the dimerization. The characteristic properties of the box ligand were supported by density functional theory (DFT) calculations of the intermediate. Axially chiral bibenzothiophenes were obtained in good yields with good enantioselectivities. 相似文献
110.