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971.
T. ?alkus E. Kazakevi?ius A. Ke?ionis V. Kazlauskien? J. Mi?kinis A. Dindune Z. Kanepe J. Ronis M. Dudek M. Bu?ko J. R. Dygas W. Bogusz A. F. Orliukas 《Ionics》2010,16(7):631-637
Li1.3Al0.15Y0.15Ti1.7(PO4)3 compound was synthesized by solid-state reaction, and ceramics were sintered. The surfaces of the ceramics were investigated by scanning electron microscopy and X-ray photoelectron spectroscopy. Li1.3Al0.15Y0.15Ti1.7(PO4)3 samples were tested in solid galvanic cells Ag|O2+CO2|Li2CO3|Li1.3Al0.15Y0.15Ti1.7(PO4)3|LiMnO2+Mn2O3|O2|Ag. The electromotive force measurements of this cell indicated that investigated samples are practically pure Li-ion conductors. Impedance spectroscopy studies have been performed in the frequency range 10?2–3·109 Hz and temperatures from ?57 °C to 334 °C. Three dispersion regions related to Li+ ionic transport in bulk, grain boundaries of the ceramics and to polarization of electrodes have been found. Total conductivity changes according to Arrhenius law in the studied temperature range, but an anomalous behavior was observed for the bulk conductivity of the ceramics. 相似文献
972.
Wei Li Ning Hua Zhu Li Xian Wang Jian Hong Ke Shuo Fu Chen Bang Hong Zhang Liang Xie 《Optics Communications》2010,283(11):2324-5212
In this paper, the spectral relation between the master and the frequency-locked slave laser (FLSL) is investigated by the conventional technique of optical intensity modulation and optical heterodyne. Experimentally, we demonstrate that under complete and stable locking condition, the lightwave of the FLSL and the sidebands of the master laser produced by the optical intensity modulation are perfectly coherent (frequency coherence). Referring to our recent studies, the lightwave of the master laser and its corresponding sidebands are also perfectly coherent. Additionally, the spectral structures of two perfectly coherent lightwaves are identical in the level of wave train. Therefore, we indirectly verify that the spectral structures of the FLSL and the master laser are identical in the level of wave train. 相似文献
973.
We designed, fabricated, and characterized a thermo-optically tunable compact (10 μm × 10 μm) silicon photonic crystal (PhC) light modulator that operates at around 1.55 μm for TE polarization. The operational principle of the device is the modulation of the cutoff frequency in a silicon-based line defect PhC. The cutoff frequency is shifted because of the thermo-optic tuning of the silicon refractive index, which is realized by localized heating on the PhC. The modulator is formed by a triangular lattice array of cylindrical air holes on a silicon-on-insulator wafer. Optical characterization was carried out, and the result clearly showed thermo-optic tuning of the cutoff frequency at around 1.55 μm. 相似文献
974.
Lu TC Ke MY Yang SC Cheng YW Chen LY Lin GJ Lu YH He JH Kuo HC Huang J 《Optics letters》2010,35(24):4109-4111
Low-temperature electroluminescence from ZnO nanowire light-emitting arrays is reported. By inserting a thin MgO current blocking layer in between ZnO nanowire and p-GaN, high-purity UV light emission at wavelength 398 nm was obtained. As the temperature is decreased, contrary to the typical GaN-based light emitting diodes, our device shows a decrease of optical output intensity. The results are associated with various carrier tunneling processes and frozen MgO defects. 相似文献
975.
Qi Wang Jinghui Yang Weiwei Yao Ke Wang Rongni Du Qin Zhang Feng Chen Qiang Fu 《Applied Surface Science》2010,256(20):5843-4934
Self-assembly of block copolymer is an effective strategy to prepare periodic structures at nanoscale. In this paper an unique and very simple method to prepare inorganic silica nanopattern is demonstrated from self-assembling of poly(styrene-block-dimethylsiloxane) (PS-b-PDMS) on the surface of silicon wafer. To simplify the patterning process, at first we obtain highly ordered PDMS microdomains, which are covered with PS layer by controlling solvent vapor annealing conditions. Following exposure to UV/O3 irradiation, nanopatterned surface consisting of silicon oxide is fabricated directly via selectively etching PS phase and converting PDMS phase into silicon oxide. As tuning the composition of the block copolymer, hexagonally packing dot and straight stripe pattern can be obtained. Finally, the time evolution from spheres morphology to aligned long cylinders is discussed. These results hold promise for nanolithography and the fabrication of nanodevices. 相似文献
976.
To improve the anterior surface biocompatibility of hydrophobic acrylic intraocular lens (IOL) in a convenient and continuous way, poly(ethylene glycol)s (PEGs) were immobilized by atmospheric pressure glow discharge (APGD) treatment using argon as the discharge gas. The hydrophilicity and chemical changes on the IOL surface were characterized by static water contact angle and X-ray photoelectron spectroscopy to confirm the covalent binding of PEG. The morphology of the IOL surface was observed under field emission scanning electron microscopy and atomic force microscopy. The surface biocompatibility was evaluated by adhesion experiments with platelets, macrophages, and lens epithelial cells (LECs) in vitro. The results revealed that the anterior surface of the PEG-grafted IOL displayed significantly and permanently improved hydrophilicity. Cell repellency was observed, especially in the PEG-modified IOL group, which resisted the attachment of platelets, macrophages and LECs. Moreover, the spread and growth of cells were suppressed, which may be attributed to the steric stabilization force and chain mobility effect of the modified PEG. All of these results indicated that hydrophobic acrylic IOLs can be hydrophilic modified by PEG through APGD treatment in a convenient and continuous manner which will provide advantages for further industrial applications. 相似文献
977.
Yuanyuan Ke Dragana S. Cvetković-Ilić Jelena Višnjić 《Linear and Multilinear Algebra》2018,66(3):447-458
In this paper, we present some necessary and sufficient conditions for the existence of the (b, c)-inverse and several representations for the (b, c)-inverse related to the group inverse. Since Mary inverse, core inverse, dual core inverse and Bott–Duffin (e, f)-inverse are all the special cases of the (b, c)-inverse, related results for these inverses are obtained. 相似文献
978.
979.
《Operations Research》(OR)是运筹与管理科学领域的顶级期刊,对其刊文进行统计分析,剖析国际运筹学科领域的主流研究机构及合作影响,探究当前研究热点问题及学科发展趋势,对于促进我国运筹学科领域的发展具有十分重要的指引作用.基于对WOS核心数据库中该期刊1996至2017年间全部刊文的统计分析,得出以下结论:近年来我国学者发文量稳步提升,表明我国运筹学科领域研究水平的显著提高,但其影响力仍有待进一步提升;机构合作、国际合作都有助于文章引文量的提升;引证分析显示柔性制造(流程柔性及效率)、巢式Logit模型的应用、网络收益管理等7个研究方向是当前、并继续成为运筹领域的研究热点. 相似文献
980.
We define a vector representation V(u)of elliptic Ding-Iohara algebra u(q,t,p).Furthermore,we construct the tensor products of the vector representations and the Fock modulesF(u)by taking the inductive limit of certain subspaces in the finite tensor products of vector representations. 相似文献