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61.
62.
Masanori Miura Takanori Koike Tsukasa Ishihara Fukushi Hirayama Shuichi Sakamoto Minoru Okada 《合成通讯》2013,43(24):3809-3820
A one‐pot synthetic procedure for 2,2′‐disubstituted biaryls was developed via a Suzuki cross‐coupling reaction of aryl triflates in a biphasic solvent system. The effects of various bases and solvents were investigated. Results showed that the Na2CO3–toluene/H2O combination gave the highest yields. 相似文献
63.
Photolysis of perfluoroazooctane with diamond powders led to chemical modification of the surface with the introduction of perfluorooctyl ester and ether functional groups, the presence of which was confirmed by means of FT-IR, XPS and 19F NMR measurements. 相似文献
64.
用浸渍法制备并采用交流阻抗、极化等技术考察了不同组成的Ni-Sm3+掺杂的CeO2(SDC) 复合镍阳极的电化学性能及相应电池的功率输出性能.结果表明,SDC掺入镍阳极后,阳极极化过电位及电池的欧姆电阻显著减小.其中阳极过电位的减小与SDC掺入镍电极引起的三相界扩展有关,但SDC的掺入同时引起了电极反应活化能的增加,造成低温下Ni-SDC的极化过电位大于纯Ni电极.高温下,Ni-SDC阳极的阻抗谱由两个半圆组成,其中高频半圆随着SDC掺入量的增加而减小,而低频环与SDC的掺入量基本无关.低温下只观察到一个高频环.高频环可能对应三相界反应,而低频环可能对应氢的解离吸附及扩散.75%(w)Ni-25%(w)SDC/La0.9Sr0.1Ga0.8Mg0.2O3(LSGM)/Sm0.5Sr0.5CoO3(SSC)在所研究的电池中具有最大功率输出密度,其值在1073、973、873 K下分别达到1.1、0.43、0.14 W•cm-2. 相似文献
65.
66.
67.
Norio Sakai Ken NagasawaReiko Ikeda Yumi NakaikeTakeo Konakahara 《Tetrahedron letters》2011,52(24):3133-3136
An InBr3-Et3SiH reducing system was developed to selectively convert aliphatic ketones to a variety of secondary alcohols in moderate to good yields. An initial mixing of InBr3 and PhSiH3 was followed by the addition of aliphatic ketones and a solvent to afford the symmetrical ether derivatives. 相似文献
68.
J.P. DuignanI.D.H. Oswald I.C. SageL.M. Sweeting K. TanakaT. Ishihara K. HiraoG. Bourhill 《Journal of luminescence》2002,97(2):115-126
There are many reports in the literature of a spectral difference between the triboluminescence (TL) spectrum and the solid-state photoluminescence (PL) spectrum of the same compound. Numerous reasons have been suggested for this difference including pressure-induced changes to Franck-Condon factors during the lifetime of the TL light emission; self-absorption of the TL emission and fracture-induced symmetry changes perturbing the local field of the TL emitting species. However, in a number of cases, the luminescent spectra were recorded on different equipment with different spectral responses, with the resolution of either luminescent spectrum rarely quoted. To avoid artificial spectral differences, care must be taken to account for the response of each equipment over the wavelength range studied, as well as any resolution difference. We have therefore measured the TL and solid-state PL spectra of sixteen TL compounds on the same spectrometer at an identical resolution. Furthermore, the solid-state photoluminescent lifetime has been determined for all samples and the implication that these values have for observing pressure-induced (Franck-Condon) luminescent spectral changes discussed. Finally, in all cases where a significant difference was observed between TL and PL spectra, either self-absorption of the TL emission or fracture-induced perturbations of the local field have been evoked to explain the difference. 相似文献
69.
We study the size dependence of the nonlinear response of weakly confined excitons for the size region beyond the long wavelength approximation regime. The observed degenerate-four-wave mixing signal of GaAs thin layers exhibits an anomalous size dependence, where the signal is resonantly enhanced at a particular thickness region. The theoretical analysis elucidates that this enhancement is due to the size-resonant enhancement of the internal field with a spatial structure relevant to the nondipole-type excitonic state. These results establish the formerly proposed new type of size dependence of nonlinear response due to the nonlocality induced double resonance. 相似文献
70.
Doping transition metal cation is known to enhance the electronic conduction of solid electrolytes, however, the ionic conduction
can also be improved by those dopants. In this investigation, the oxide ion conductivity of LaGaO3 based oxide doped with transition metal cations such as Fe, Co, Ni, Mn, and Cu for the Ga site was studied. It was found
that doping Co or Fe is effective for enhancing the oxide ion conductivity. The improved oxide ion conductivity may be induced
by the improved mobility of oxide ion. Among examined transition metal cations, cobalt is the most adequate cation as a dopant
for the Ga site of LSGM. Considering the conductivity and the transport number, the optimized composition is found to be La0.8Sr0.2Ga0.8Mg0.115Co0.085O3. In this work, application of Co2+ doped LSGM as the electrolyte of internally reformed fuel cells was also investigated. Improvement in oxide ion conductivity
is effective for enhancing the power generation characteristics.
Paper presented at the 4th Euroconference on Solid State Ionics, Renvyle, Galway, Ireland, Sept. 13–19, 1997 相似文献