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861.
Ryo Tamaki Yuko Arai Daisuke Ichikawa Masaya Inoue Hideyuki Kunugita Kazuhiro Ema 《Journal of luminescence》2008,128(5-6):842-844
Exciton polariton in an organic–inorganic multiple-quantum-well (MQW) single crystal (C4H9NH3)2PbBr4 at low temperature has been investigated by photoluminescence excitation (PLE), reflection, and time-resolved photoluminescence measurements. Since (C4H9NH3)2PbBr4 has ideal two-dimensional excitons with an extremely large oscillator strength and forms self-organized MQW with a very short well-period (d~10 Å), polaritonic coupling among excitons is strong and extends over a large number of wells. Therefore, observed MQW polariton features were the same as those of bulk polaritons. We have also investigated relaxation dynamics of the MQW polariton in the same framework as discussions on bulk polaritons. 相似文献
862.
863.
Toshihiko Yoshimura Kousuke Takeda Hitoshi Sasaki Masaya Tatsui 《Applied Surface Science》2009,256(1):112-115
High compression strength and high ductility spherical nanoballs were produced by electric arc discharge with a carbon electrode containing silicon, oxygen, potassium, and sodium. Compression tests of the nanoballs were conducted by application of a load to nanoballs inserted between two polished sample stages with nanolevel surface roughness. Experimental estimation of the compression strength of nanomaterials was enabled by careful selection and polishing of the sample stage materials. 相似文献
864.
Tomoaki Sawabe Koshi Okamura Tomoki Sueyoshi Takashi Miyamoto Kazuhiro Kudo Nobuo Ueno Masakazu Nakamura 《Applied Physics A: Materials Science & Processing》2009,95(1):225-232
Vertical electrical conduction in Au/(polycrystal-line pentacene)/Al diode structures and the influence of the kinetic energy
of incident Au atoms on the conduction property have been comprehensively studied using current–voltage–temperature (I–V–T) measurements, ultraviolet photoelectron spectroscopy (UPS), atomic-force-microscope (AFM) current imaging, etc. In the I–V characteristics, a symmetrical ohmic current component appeared when a low voltage was applied, and a super-linear one appeared
when a high positive voltage was applied to Au. The component in the high-forward-voltage region was concluded to be a thermionic
emission of holes from Au with a 0.23-eV injection barrier, which is the normal hole conduction through the highest occupied
molecular orbital of pentacene. On the other hand, the ohmic component was concluded to be a metal-like electron transport
through high-density gap states at grain boundaries which were induced by the Au penetration into pentacene. UPS and I–V–T measurements clearly indicated the generation of the gap states and the enhancement of their density by the reduction of
Au kinetic energy. For vertical-type devices with polycrystalline organic films, the ohmic conduction through the grain boundary
will increase the leakage current. On the contrary, it possibly enhances the carrier injection in lateral-type transistors
in the case of top-contact configuration. 相似文献
865.
Naoto Hayashi Naoki Okamoto Masaya Onoue Kensuke Yamamoto Junro Yoshino 《Tetrahedron letters》2019,60(25):1663-1666
The 1:0.5 hydrated crystal (I) of 2,2′-(anthra[2,3-b:7,6-b′]difuran-5,11-diylidene)dimalononitrile (1) showed aggregation-induced emission (AIE). However, the structurally similar non-solvated crystal (II) did not show AIE. We found that this was because the lack of water of crystallization changed the geometry of the intermolecular π contacts from two-dimensional in I to three-dimensional in II. 相似文献
866.
Kumazawa K Yoshizawa M Liu HB Kamikawa Y Moriyama M Kato T Fujita M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(8):2519-2524
Compound 1a, which possesses a triphenylene core and six tetraethyleneoxide side chains, shows efficient ionization of M(II)-containing (M=Pd, Pt) complexes in electrospray ionization mass spectrometry (ESI-MS). The molecular ion peaks [M]+, which are hardly detected under common ESI-MS conditions, are clearly observed as their [M x (1a)n]+ (n=1-4) adducts. UV-visible and NMR studies reveal that the electron-rich triphenylene core of 1a binds to the electron-deficient frameworks of the M(II) complexes in solution, giving rise to charge transfer (CT) complexes. We suggest that 1a stabilizes the complexes and promotes efficient ionization through unique donor-acceptor molecular recognition. 相似文献
867.
Kamegawa T Sakai T Matsuoka M Anpo M 《Journal of the American Chemical Society》2005,127(48):16784-16785
Unique inorganic-organic hybrid mesoporous materials incorporating arenetricarbonyl complexes [-C6H4M(CO)3-] (M = Cr, Mo) within their mesoporous frameworks have been successfully prepared by a simple CVD treatment of the phenylene-bridged organosilica mesoporous materials with metal hexacarbonyls [M(CO)6] (M = Cr, Mo). FT-IR and UV-vis investigations revealed that the arenetricarbonyl complexes exist stably even at temperatures above 473 K under vacuum. 相似文献
868.
The electrochemical characteristics of various kinds of multilayers of gold nanoclusters (GNCs) were investigated. Two types of gold nanoclusters, one covered by self-assembled monolayers (SAMs) of mercaptoundecanoic acid (MUA), hexanethiol (C6SH), and ferrocenylhexanethiol (FcC6SH), MHF-GNC, and the other with MUA and C6SH, MH-GNC, were used. The multilayers were constructed on a Au(111) surface based on a carboxylate/metal cation (Cu++)/carboxylate or carboxylate/cationic polymer (poly(allylamine hydrochloride):PAH)/carboxylate electrostatic interaction. While the multilayers constructed by the former method were stable only in nonaqueous solutions, those constructed by the latter method were stable even in aqueous solutions. Electrochemical measurements of the multilayers of MHF-GNCs showed a pair of waves corresponding to the redox of the ferrocene group around 350-480 mV and the charge of these peaks, i.e., the amount of adsorbed GNC, increased linearly with the construction cycle up to 6 cycles in the former and to 18 cycles in the latter. A rather reversible redox response of the ferrocene moiety was observed even at the gold electrodes with five GNC layers of two different sequences in which MHF-GNC exists as the layer closest to the gold electrode, ie., the first layer, or as the outermost layer with MH-GNC in the other layers. These results show the facile transfer of electrons and ions through the multilayers of the SAM-covered GNCs and electron transfer between the ferrocene moiety and the Au(111) electrode takes place through the GNC cores by hopping. 相似文献
869.
870.
[chemical reaction: see text]. A toluene-coordinated silyl borate, [Et3Si(toluene)]B(C6F5)4, demonstrated catalytic activities significantly higher than those of Me3SiOTf and Me3SiNTf2 in Mukaiyama aldol and Diels-Alder reactions. 相似文献