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101.
A. Kitada Y. Tsujimoto T. Yamamoto Y. Kobayashi Y. Narumi K. Kindo A.A. Aczel G.M. Luke Y.J. Uemura Y. Kiuchi Y. Ueda K. Yoshimura Y. Ajiro H. Kageyama 《Journal of solid state chemistry》2012
We will present the synthesis, structure and magnetic properties of a new quadruple-layered perovskite (CuCl)Ca2NaNb4O13. Through a topotactic ion-exchange reaction with CuCl2, the precursor RbCa2NaNb4O13 presumably having an incoherent octahederal tliting changes into (CuCl)Ca2NaNb4O13 with a 2ap×2ap×2cp superstructure (tetragonal; a=7.73232(5) Å, c=39.2156(4) Å). The well-defined superstructure for the ion-exchanged product should be stabilized by the inserted CuCl4O2 octahedral layers that firmly connect with neighboring perovskite layers. Magnetic studies show the absence of long-range magnetic ordering down to 2 K despite strong in-plane interactions. Aleksandrov′s group theory and Rietveld refinement of synchrotron X-ray diffraction data suggest the structure to be of I4/mmm space group with in-phase tilting along the a and b axes, a two-tilt system (++0). 相似文献
102.
Controlled Crystallization of Cyano‐Bridged Cu–Pt Coordination Polymers with Two‐Dimensional Morphology
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Mohamed B. Zakaria Dr. Ming Hu Dr. Yoshihiro Tsujimoto Prof. Yoshio Sakka Dr. Norihiro Suzuki Yuichiro Kamachi Dr. Masataka Imura Dr. Shinsuke Ishihara Prof. Katsuhiko Ariga Prof. Yusuke Yamauchi 《化学:亚洲杂志》2014,9(6):1511-1514
Two‐dimensional (2D) coordination polymers (CPs) have a highly accessible surface area that permits guest molecules to effectively access the micropores in the CPs. Here we report a bottom‐up synthesis of 2D cyano‐bridged Cu–Pt CP nanoflakes using trisodium citrate as a chelating agent, which controls the nucleation rate and the crystal growth. The lateral sizes of the CP nanoflakes are controlled by changing the amount of trisodium citrate used. We strongly believe that our method will be useful for the preparation of other types of 2D CP nanoflakes. The 2D CPs have many active sites for catalytic and electrochemical reactions, and furthermore the assembled CPs can be used as membrane filters. 相似文献
103.
Guoqing Li Hitoshi Saito Shunji Ishio Toshiyuki Shima Koki Takanashi 《Journal of magnetism and magnetic materials》2006
Anomalous magnetization processes and non-symmetrical domain wall displacements in the minor loop of L10 FePt particulate films were investigated by magnetization measurements and in situ magnetic force microscopy. Magnetization (M) decreases dramatically on increasing the magnetic field to ∼3 kOe after which M becomes small and constant in the range of 5–20 kOe as observed in the successive measurement of minor loops. The domain wall displacement is non-symmetrical with respect to the field direction. The anomalous magnetization behavior was attributed to the non-symmetrical domain wall displacement and large magnetic field required for domain wall nucleation. Energy calculations from modeling suggest that non-symmetrical domain wall displacement is caused by the existence of metastable domains in which the domain edges are stuck to the particle boundaries. 相似文献
104.
New donor-acceptor dyads containing tetrathiafulvalene (TTF) and 2,5-diphenyl-1,3,4-oxadiazole (PPD) moieties were synthesized to develop new photoconducting materials. Crystal structure analysis indicated the highly planar molecular skeleton of the dyad. Fluorescence from the PPD part was almost quenched by the intramolecular electron transfer from the TTF part to the PPD part. Photoelectrochemical measurements indicate that cathodic photocurrents can be generated from a thin film of the dyad spin-coated on ITO electrode. 相似文献
105.
G Fukuhara T Nakamura Y Kawanami C Yang T Mori H Hiramatsu Y Dan-Oh K Tsujimoto Y Inoue 《Chemical communications (Cambridge, England)》2012,48(73):9156-9158
Photocyclodimerization of 2-anthracenecarboxylate tethered to a cyclic nigerosylnigerose scaffold gave a single chiral cyclodimer (out of two achiral and two chiral stereoisomers) in 99% optical and 96% chemical yields, achieving the ultimate stereocontrol of the supramolecular photochirogenesis in aqueous solution at 25 °C. 相似文献
106.
[Structure: see text] A trichloroacetamide group was converted to an isocyanate, which was in situ captured by a variety of alcohols in the presence of CuCl and n-BuN4Cl to afford the corresponding carbamates. The scope and limitation of this transformation are also described. 相似文献
107.
The thermal expansion, spontaneous volume magnetostriction ωs, forced volume magnetostriction and Young's modulus of amorphous Fe-B, Fe-P, Co-B and (Fe-M)77Si10B13 (M = Cr, Mn, Co, Ni) alloys have been measured to make clear the magnetovolume effect in transition metal-metalloid amorphous alloys. The thermal expansion coefficient α, ωs and are dependent on the number of d-electrons per transition metal atom neff calculated based on the charge transfer model. The neff vs. α, ωs and curves are quite similar to the corresponding curves in fcc alloys. The maxima in those curves are, however, found at neff ≈ 8.2 for the amorphous alloys in contrast with neff ≈ 8.7 for the fcc Fe-Ni alloys. On the other hand, Young's modulus measured under the saturation of magnetization is governed by the molar volume, irrespective of neff. The magnetovolume effect in transition metal-metalloid amorphous alloys is discussed in connection with the instability of ferromagnetism of amorphous Fe. 相似文献
108.
109.
Optical switches are useful for various optical systems. This paper describes a new form of optical transmission system, using 1 × 6 optical switch with built-in optical multiplexer. The insertion loss of the optical switch was 3.1 dB (including filter loss of 1.4 dB). This switch is useful for a traffic monitoring system, and its transmission characteristics were measured. The measured signal-to-noise ratio is 44 dB when the switch is applied to a 2-km video transmission line. 相似文献
110.