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71.
Synthesis and Self‐Assembly of Cyclic 2,7‐Anthrylene Ethynylene 1,3‐Phenylene Ethynylene Trimer with a Planar Conformation
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Yuta Takaki Ryota Ozawa Dr. Takashi Kajitani Prof. Takanori Fukushima Prof. Masaaki Mitsui Prof. Kenji Kobayashi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(47):16760-16764
Cyclic arylene ethynylene hexamer 1 , composed of alternating 2,7‐anthrylene ethynylene units and meta‐phenylene ethynylene units, was synthesized. It shows C3 symmetry and possesses a flat and rigid conformation with a large equilateral triangle‐like cavity. Macrocycle 1 self‐associates through π–π stacking interactions between the anthracene‐containing macrocyclic aromatic cores with indefinite‐association constant KE=6980 m ?1 in CDCl3 at 303 K. Macrocycle 1 also self‐assembles into π‐stacked nanofibers in the drop‐cast film. 相似文献
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73.
Kazuhisa Sato Shunya Tashiro Shuhei Matsunaga Yohei Yamaguchi Takanori Kiguchi Toyohiko J. Konno 《哲学杂志》2018,98(21):1945-1960
We have studied three-dimensional (3D) structures and growth processes of 14H-type long-period stacking order (LPSO) formed in Mg97Zn1Gd2 cast alloys by single tilt-axis electron tomography (ET) using high-angle annular dark-field scanning transmission electron microscopy. Evolution of the solute-enriched stacking faults (SFs) and the 14H LPSO by ageing were visualised in 3D with a high spatial resolution in multi-scale fields of views from a few nanometres to ~10 μm. Lateral growth of the solute-enriched SFs and the LPSO in the (0?0?0?1)Mg plane is notable compared to the out-of-plane growth in the [0?0?0?1]Mg direction. The 14H LPSO grows at the cost of decomposition of the (Mg, Zn)3Gd-type precipitates, and accompany a change of in-plane edge angles from 30 to 60°. We have updated the Time–Temperature–Transformation diagram for precipitation in Mg97Zn1Gd2 alloys: starting temperatures of both solute-enriched SFs and LPSO formation shifted to a shorter time side than those in the previous diagram. 相似文献
74.
The wave-splitting phase-shifting digital holography using a pixelated microretarder array is proposed. By using four intensity
images recorded by the pixelated microretarder array, Stokes parameters of the incident wave can be calculated. The fully
complex amplitude distribution of the object wave can be obtained by using Stokes parameters, if the polarization states of
the object and reference waves are linear and orthogonal. Two sets of experimental results are provided to verify the feasibility
of the proposed method. One is the result for a movie recording using a CW laser and the other is the result for instant recording
using a single pulsed laser. 相似文献
75.
Sun-Chan Jeong Ichiro Katayama Hirokane Kawakami Yutaka Watanabe Hironobu Ishiyama Nobuaki Imai Yoshikazu Hirayama Hiroari Miyatake Masao Sataka Hiroyuki Sugai Satoru Okayasu Shin-Ichi Ichikawa Katsuhisa Nishio Shinichi Mitsuoka Takamitsu Nakanoya Takashi Hashimoto Takanori Hashimoto Masahito Yahagi 《Solid State Ionics》2009,180(6-8):626-630
The diffusion coefficients of Li in the NaTl-type Li intermetallic compound of β-LiGa have been measured by using a short-lived radioactive diffusion tracer. As the tracer, the α-emitting radioisotope of 8Li delivered as the energetic and pulsed beam from Tokai Radioactive Ion Accelerator Complex (TRIAC) was implanted into the β-LiGa compounds with the composition in the range of about 43 to 54 at.% Li. By analyzing the time-dependent yields of the α-particles measured according to the repetition cycle of the beam, the tracer diffusion coefficients were extracted over the wide range of Li composition. Abnormal composition-dependence of Li diffusion coefficients in β-LiGa was observed; the stoichiometric β-LiGa showed the highest diffusivity of Li. By referring to the composition-dependent diffusivity of Li in the iso-structural β-LiAl and β-LiIn, we could identify the abnormal diffusion of Li in very Li-poor composition of β-LiGa. The anomaly has been discussed qualitatively in terms of the formation of defect complex and the interaction between the constitutional defects. 相似文献
76.
Katsumi Katoh Seiichiro Nagayama Eiko Higashi Katsuyuki Nakano 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1239-1244
In the hydrosilylation of 1,6-divinyl(perfluorohexane) (FDV) with trichlorosilane (TCS) in the presence of catalytic chloroplatinic acid (Pt-Cat) under an air atmosphere (0.99 MPa), a runaway reaction accompanied by a severe pressure release occurred when Fe2O3 was present as an impurity in the system. In this study, we investigated the mechanism of action of Fe2O3 on this hydrosilylation by monitoring the thermal behavior of TCS/FDV/Pt-Cat/Fe2O3 mixtures with various compositions, using an accelerating rate calorimeter (ARC). In the case of TSC/FDV/Pt-Cat, a typical hydrosilylation composition in the industrial process, heat release, possibly due to hydrosilylation, began at 90 °C. On the other hand, for TCS/FDV/Pt-Cat/Fe2O, the heat release due to hydrosilylation was hardly observed, but abrupt heat and pressure releases occurred at higher temperatures (>170 °C). Like TCS/FDV/Pt-Cat/Fe2O3, TCS/FDV, which contain neither Pt-Cat nor Fe2O3, released heat and pressure at high temperatures (>210 °C), while the heat and pressure release rates were comparatively low. From these results, the runaway reaction may occur when hydrosilylation is prevented, and Fe2O3 behaves as a negative catalyst for hydrosilylation. In the FT-IR spectrum of TCS/FDV/Pt-Cat/Fe2O3 after heating, an absorption peak at approximately 1,710 cm?1, which may be attributed to a carbonyl group, was observed. Thus, it is considered that the runaway reaction observed during the hydrosilylation results from the action of Fe2O3 as a negative catalyst for hydrosilylation as well as as an oxidation catalyst for the by-product generated from the reaction between TCS and FDV. 相似文献
77.
Katsumi Katoh Nobuyuki Saeki Eiko Higashi Yuki Hirose Masahiko Sugimoto Katsuyuki Nakano 《Journal of Thermal Analysis and Calorimetry》2013,113(3):1275-1279
As a fundamental study on the development of dismantlable adhesives containing chemically reactive materials, the thermal behavior and dismantlability of an epoxy adhesive containing one of the twenty-seven inorganic salts (chlorides, perchlorates, and nitrates) were observed. In the thermal behavior measured by the differential scanning calorimetry, epoxy adhesives with inorganic salts containing iron, copper, zinc, and aluminum cations released heats of reaction at lower temperatures than the adhesive alone or the adhesives with other inorganic salts. Since such inorganic salts were considered to be effective candidates as fillers in dismantlable adhesives, the adhesion strengths of their mixtures with the adhesive were observed after heat aging at 270 °C for 30 min. The results showed that both chloride and perchlorate salts specifically decreased the adhesion strength after heating. On the other hand, the effect of nitrate salts on the decrease in adhesion strength was low in comparison with the chloride and perchlorate salts. 相似文献
78.
Mitsunori Oda Takanori Kajioka Kazuya Ikeshima Ryuta Miyatake Shigeyasu Kuroda 《合成通讯》2013,43(13):2335-2343
The trimethylsilyl enol ether of l-acetylcyclohepta-1,3,5-triene was transformed to 3,3-dialkyl-1,2,3,8-tetrahydroazulen-1-one by a two-step sequence involving the Mukaiyama aldol reaction with ketones and the subsequent Nazarov cyclization. 相似文献
79.
80.