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41.
Prof. Dr. Masahiro Sadakane Sachie Moroi Yoshifumi Iimuro Dr. Natalya Izarova Prof. Dr. Ulrich Kortz Prof. Dr. Shinjiro Hayakawa Kazuo Kato Dr. Shuhei Ogo Dr. Yusuke Ide Prof. Dr. Wataru Ueda Prof. Dr. Tsuneji Sano 《化学:亚洲杂志》2012,7(6):1331-1339
Ruthenium(III)‐substituted α‐Keggin‐type silicotungstates with pyridine‐based ligands, [SiW11O39RuIII(Py)]5?, (Py: pyridine ( 1 ), 4‐pyridine‐carboxylic acid ( 2 ), 4,4′‐bipyridine ( 3 ), 4‐pyridine‐acetamide ( 4 ), and 4‐pyridine‐methanol ( 5 )) were prepared by reacting [SiW11O39RuIII(H2O)]5? with the pyridine derivatives in water at 80 °C and then isolated as their hydrated cesium salts. These compounds were characterized using cyclic voltammetry (CV), UV/Vis, IR, and 1H NMR spectroscopy, elemental analysis, titration, and X‐ray absorption near‐edge structure (XANES) analysis (Ru K‐edge and L3‐edge). Single‐crystal X‐ray analysis of compounds 2 , 3 , and 4 revealed that RuIII was incorporated in the α‐Keggin framework and was coordinated by pyridine derivatives through a Ru? N bond. In the solid state, compounds 2 and 3 formed a dimer through π? π interaction of the pyridine moieties, whereas they existed as monomers in solution. CV indicated that the incorporated RuIII–Py was reversibly oxidized into the RuIV–Py derivative and reduced into the RuII–Py derivative. 相似文献
42.
Tadamasa Toma Yoshio Furuya Wataru Watanabe Kazuyoshi Itoh Junji Nishii Kenichi Hayashi 《Optical Review》2000,7(1):14-17
It is known that local refractive index change occurs when femtosecond laser pulses with extremely high peak power are launched into glass. We focused 130-femtosecond laser pulses of 800 nm into the bulk of glass and examined the shape of the induced refractive index change. We found that the length of the spot of the refractive index change along the optical axis reached about 30 μm despite the diameter being about 2 μm. To estimate the distribution of induced refractive index change, we fabricated Bragg grating by scanning the focused spot and calculated the amount of the change by applying Kogelnik’s coupled mode theory to the measured diffraction efficiencies of the higher order diffracted beams. 相似文献
43.
Let H be a real Hilbert space and let T: H→2H be a maximal monotone operator. In this paper, we first introduce two algorithms of approximating solutions of maximal monotone operators. One of them is to generate a strongly convergent sequence with limit vT−10. The other is to discuss the weak convergence of the proximal point algorithm. Next, using these results, we consider the problem of finding a minimizer of a convex function. Our methods are motivated by Halpern's iteration and Mann's iteration. 相似文献
44.
Prof. Hisahiro Sasabe Prof. Yuki Kato Dr. Yuichiro Watanabe Tatsuya Ohsawa Dr. Naoya Aizawa Prof. Wataru Fujiwara Dr. Yong-Jin Pu Prof. Hiroshi Katagiri Prof. Junji Kido 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(71):16294-16300
Exploration of pure metal-free organic molecules that exhibit strong room-temperature phosphorescence (RTP) is an emerging research topic. In this regard, unveiling the design principles for an efficient RTP molecule is an essential, but challenging, task. A small molecule is an ideal platform to precisely understand the fundamental role of each functional component because the parent molecule can be easily derivatized. Here, the RTP behaviors of a series of 3-pyridylcarbazole derivatives are presented. Experimental studies in combination with theoretical calculations reveal the crucial role of the n orbital on the central pyridine ring in the dramatic enhancement of the intersystem crossing between the charge-transfer-excited singlet state and the locally excited triplet states. Single-crystal X-ray crystallographic studies apparently indicate that both the pyridine ring and fluorine atom contribute to the enhancement of the RTP because of the restricted motion owing to weak C−H⋅⋅⋅N and H⋅⋅⋅F hydrogen-bonding interactions. The single crystal of the fluorine-substituted derivative shows an ultra-long phosphorescent lifetime (τP) of 1.1 s and a phosphorescence quantum yield (ΦP) of 1.2 %, whereas the bromine-substituted derivative exhibits τP of 0.15 s with a ΦP of 7.9 %. We believe that this work provides a fundamental and universal guideline for the generation of pure organic molecules exhibiting strong RTP. 相似文献
45.
Quasi-solid-state dye-sensitized solar cells using room temperature molten salts and a low molecular weight gelator 总被引:1,自引:0,他引:1
Kubo W Kitamura T Hanabusa K Wada Y Yanagida S 《Chemical communications (Cambridge, England)》2002,(4):374-375
A dye-sensitized solar cell fabricated using the room temperature molten salt, 1-hexyl-3-methylimidazolium iodide, iodine and a low molecular weight gelator as a quasisolid-state electrolyte showed a 5.0% light-to-electricity conversion efficiency under AM 1.5 irradiation, and high-temperature stability. 相似文献
46.
Hiroshi Onoue Masayuki Narisada Shoichiro Uyeo Hiromu Matsumura Kyo Okada Toshisada Yano Wataru Nagata 《Tetrahedron letters》1979,20(40):3867-3870
Allylazetidinones , , prepared by coupling of allylcoppers with chloroazetidinones , , were converted into carbapenem esters , – using an Emmons-Horner reaction to introduce the 6-side chain and an intramolecular Wittig reaction to form the carbapenem ring system. 相似文献
47.
Toshinobu?YogoEmail author Reimon?Fukuzawa Wataru?Sakamoto Shin-ichi?Hirano 《Journal of nanoparticle research》2005,7(6):633-640
Nanocrystalline BaTiO3 particles modified with polarizable ligands were synthesized through hydrolysis of modified metal–organics below 100°C. BaTiO3 precursor was synthesized from barium metal, titanium isopropoxide and polarizable ligands in a mixture of ethanol and 2-ethoxyethanol.
The modified Ba–Ti complex alkoxide was hydrolyzed yielding BaTiO3 particles modified with organics. The crystallinty of nanometer-sized particles was dependent upon the hydrolysis conditions,
and increased with increasing water amount and time. The nanocrystalline particles were identified to be BaTiO3 by X-ray diffraction (XRD) and electron diffraction. A fluid consisting of modified BaTiO3 particles and silicone oil revealed a typical electrorheological (ER) behavior on applying DC field. The ER behavior was
found to depend upon the kind of ligand. 4-Fluorobenzyloxy modifier revealed the highest yield stress in the ER measurement
among 4-substitued benzyloxy ligands examined. 相似文献
48.
Tanaka Y Hoshino W Shimizu S Youfu K Aratani N Maruyama N Fujita S Osuka A 《Journal of the American Chemical Society》2004,126(10):3046-3047
When heated, bis-Cu(II) octaphyrin(1.1.1.1.1.1.1.1) is quantitatively split into two Cu(II) porphyrins both in solution and film states, which is accompanied by large absorption spectral changes. 相似文献
49.
50.
Hayashi Y Tsuboi W Shoji M Suzuki N 《Journal of the American Chemical Society》2003,125(37):11208-11209
High pressure induced by water-freezing has been successfully applied to the direct catalytic asymmetric-three component List-Barbas-Mannich reaction, in which higher yield and better enantioselectivity can be realized than those from the reaction at room temperature under 0.1 MPa. 相似文献