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401.
Rational Molecular Design and Synthesis of Highly Thermo‐ and Photostable Near‐Infrared‐Absorbing Heptamethine Cyanine Dyes with the Use of Fluorine Atoms
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Prof. Dr. Kazumasa Funabiki Kazutaka Yagi Masato Ueta Mitsuru Nakajima Masako Horiuchi Dr. Yasuhiro Kubota Prof. Dr. Masaki Mastui 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(35):12282-12285
Highly thermo‐ and photostable, near‐infrared‐absorbing heptamethine cyanine dyes were achieved with the use of fluorine‐containing components. In particular, one prepared heptamethine cyanine dye, bearing a tetrakis(pentafluorophenyl)borate as a counter anion and an N‐ethyl‐2,2,2‐trifluoroacetamido group at the meso position, showed not only a high decomposition temperature (Tdt), but also very high photostability toward white LED irradiation. 相似文献
402.
Chemical braking occurs in a dilute solution during a structural change of ethynylhelicene (M)-nonamer from the metastable double-helix state to the random-coil state, being at equilibrium, where the reaction is initially rapid and then substantially retard. The chemical braking is derived from the competitive chemical reaction system in dilute solution: An energetically uphill self-catalytic reaction to form double-helix and the downhill reaction to form the random-coil. 相似文献
403.
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405.
L X-ray spectra of iodine and antimony compounds were measured using a doublecrystal spectrometer, L4 X-rays emitted from the valence 5p electrons were found to be sensitive to the chemical environment. The L4/L3, L1/L1 and L2,15/L1 intensity ratios were remarkably changed in various compounds of these elements. L4 energies of iodine compounds were shifted with the increase of the formal oxidation number. 相似文献
406.
Eiichi Yagi 《Hyperfine Interactions》1994,84(1):43-45
The behaviour of hydrogen in metals has been investigated by a channelling method utilizing a nuclear reaction1H(11B, ). The results are briefly summarized. 相似文献
407.
Daisuke Nishio-Hamane M. Katagiri K. Niwa A. Sano-Furukawa T. Okada T. Yagi 《高压研究》2013,33(3):379-388
The post-corundum phase transition has been investigated in Ti2O3 on the basis of synchrotron X-ray diffraction in a diamond anvil cell and transmission electron microscopy. The new polymorph of Ti2O3 was found at about 19 GPa and 1850 K, and this phase was stable even at about 40 GPa. A new polymorph of Ti2O3 can be indexed on a Pnma orthorhombic cell, and the unit-cell parameters are a=7.6965 (19) Å, b=2.8009 (9) Å, c=7.9300 (23) Å, V=170.95 (15) Å3 at 19 GPa, and a=7.8240 (2) Å, b=2.8502 (1) Å, c=8.1209 (3) Å, V=181.10 (1) Å3 at ambient conditions. The Birch–Murnaghan equation of state yields K 0=206 (3) GPa and K′0=4 (fixed) for corundum phase, and K 0=296 (4) GPa and K′0=4 (fixed) for the post-corundum phase. The molar volume decreases by 12% across the phase transition at around 20 GPa. The structural identification was carried out on a recovered sample by the Rietveld method, and a new polymorph of Ti2O3 can be identified as Th2S3-type rather than U2S3-type structure. The transition from corundum-type to Th2S3-type structure accompanies the drastic change of the form of polyhedron: from TiO6 octahedron in the corundum-type to TiO7 polyhedron in the Th2S3-type structures. 相似文献
408.
Abstract The electrical resistivity and the Hall coefficient of slightly reduced rutile crystals were measured in the temperature range between about 2 °K and 370 °K. The time of reduction treatments between 900 °C and 1300 °C was usually as long as 300 hrs, which assures the homogeneous reduction of crystals, The conduction mechanisms in three temperature ranges, i. e. 1. 9~3°K, 3~100°K and 100~250°K, were discussed in terms of lattice defects evidenced by ESR studies. 相似文献
409.
Kazunori Mukasa Katsunori Imamura Iwao Shimotakahara Takeshi Yagi Kunio Kokura 《Journal of Optical and Fiber Communications Reports》2006,3(5):292-339
This paper gives an overview of IDF/RDF fiber design and development for submarine system. It starts with the concept of dispersion
management line and its difference from the conventional DCF used in a module. Then it reviews the fiber design details and
optical properties of various types of fibers used as parts of dispersion management lines. Fiber splicing issues using MFD
expanding method and a brief summary of transmission experiments using the dispersion management lines are also included.
Finally, we discussed a medial dispersion alternative comprising a positive and negative medial dispersion fiber and future
optical properties improvements possibilities. 相似文献
410.
Kunihiro Senda Masayoshi Ishida Youichi Nakasu Masaaki Yagi 《Journal of magnetism and magnetic materials》2006
The influence of shearing on the magnetic properties and domain structure of 0.5 mm thick non-oriented electrical steel was studied. In the region from 1 to 1.4 mm from the sheared edge, a striped domain pattern that indicated the existence of elastic strain was observed. From the degradation tendency of flux density with respect to shearing width, the width of the degraded region near the edge increased as the magnetic field decreased. These results suggested that the change in the flux density at high magnetic fields over 300 A/m were mainly dependent on the characteristics of the edge vicinity where the domain pattern was influenced by shearing. 相似文献