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991.
H. S. Wang Y. G. Zhang S. H. Wu X. T. Lou Z. G. Zhang Y. K. Qin 《Applied physics. B, Lasers and optics》2010,100(3):637-641
A linear relationship between concentration of sulfur dioxide (SO2) and optical parameter (OP) is established using the Beer–Lambert law. The SO2 measuring system is set up to measure the concentration of sulfur dioxide in the wavelength range 275–315 nm. Experimental
results indicate that the detection limit of the sulfur dioxide measuring system is below 0.2 ppm per meter of path length,
and the measurement precision is better than ±1%. The proposed SO2 measuring method features limited interference from other gases and dust, and high stability and short response time. 相似文献
992.
H. C. Guo X. H. Zhang S. H. Tang Y. Q. Qin Y. Y. Zhu 《Applied physics. B, Lasers and optics》2010,98(2-3):253-259
With the nonlinear diffraction concept, we present a diffractive study of optical parametric interactions in nonlinear photonic crystals. The nonlinear diffraction concept enables the design of complicated nonlinear photonic crystal structures in an intuitive way. We show that there are two basic linear sequences, the anti-stacking and the para-stacking sequences, existing in a one-dimensional structure; and we present the realization of multiple phase-matching resonances in the combination of the two basic sequences. The parameters affecting the structure factor of a two-dimensional nonlinear photonic crystal are investigated, which indicate that not only the Ewald construction but also the relative domain size determines two-dimensional nonlinear diffractions. 相似文献
993.
We report the synthesis, structure, microstructure, chemical stability in H2O and CO2, and electrical transport properties of an oxide ion-conducting perovskite-related structure Ba3In2MO8 (M = Zr, Ce, Zr0.5Ce0.5). Powder X-ray diffraction confirmed the formation of a simple cubic perovskite-like structure for Ba3In2ZrO8 (a = 4.205(9) ?), Ba3In2CeO8 (a = 4.234(1) ?), and Ba3In2Zr0.5Ce0.5O8 (a = 4.285(8) ?). The increase in lattice constant is consistent with the Shannon’s ionic radius trend. Among the three samples
investigated, Ba3In2ZrO8 was found to be stable against reaction with pure CO2 at elevated temperature, while the Ce and 1:1 Zr and Ce compounds were unstable at 600 °C. Ba3In2ZrO8, Ba3In2CeO8, and Ba3In2Zr0.5Ce0.5O8 were found to be chemically unstable in H2O at about 50 °C. The bulk electrical conductivity of the samples prepared at different temperatures was found to be nearly
the same; the total conductivity (bulk + grain–boundary + electrode) seems to change with sintering temperature. Both Ba3In2ZrO8 and Ba3In2CeO8, prepared at 1,400 °C, exhibited comparable electrical conductivity of about 6 × 10−3 S cm−1 at 800 °C, which is comparable to that of conventional Y2O3-doped ZrO2 electrolyte. These compounds are very promising electroltes, provided that their chemical and mechnical stabitities are improved
without losing any ionic conductivity. 相似文献
994.
Xinman Chen Guangheng Wu Hailei Zhang Ni Qin Tao Wang Feifei Wang Wangzhou Shi Dinghua Bao 《Applied Physics A: Materials Science & Processing》2010,100(4):987-990
We report on reversible bipolar resistance switching effects in multiferroic BiFeO3 thin films without electroforming. The BiFeO3 thin films with (110) preferential orientation were prepared on LaNiO3-electrodized Si substrates with a Pt/BiFeO3/LaNiO3 device configuration. The resistance ratio of high resistance state (HRS) to low resistance state (LRS) of the devices was
as high as three orders of magnitude. The dominant conduction mechanisms of LRS and HRS were dominated by ohmic behavior and
trap-controlled space charge limited current, respectively. The resistance switching mechanism of the devices was discussed
using a modified Schottky-like barrier model taking into account the movement of oxygen vacancies. 相似文献
995.
Zu-Hua Yang Chao-Yun Long Shuei-Jie Qin Zheng-Wen Long 《International Journal of Theoretical Physics》2010,49(3):644-651
The DKP equation with Dirac oscillator potential for spin-0 particles has been studied when both space-space noncommutativity
and momentum-momentum noncommutativity are considered. The exact wave functions and corresponding energy levels have been
found. Due to the noncommutative effect, the energy spectrum is not degenerate. 相似文献
996.
Melamine is a toxic compound to both animals and human beings, and is connected to various diseases, such as kidney stones and bladder cancer. For the efficient detection of melamine, we have developed a novel sensitive cucurbit[7]uril (CB7) sensor with a detection limit at 0.20 μg mL−1, and applied it to detect melamine in tainted milk. Fluorescence studies indicate that CB7 forms complex with melamine in a 1:1 mole ratio. The binding constant at various temperatures has been calculated and the interaction mechanism has been discussed based on molecular modeling result. 相似文献
997.
Qin H Shi J Cao Y Wu K Zhang J Plummer EW Wen J Xu ZJ Gu GD Guo J 《Physical review letters》2010,105(25):256402
High-resolution electron energy loss spectroscopy measurements have been carried out on an optimally doped cuprate Bi(2)Sr(2)CaCu(2)O(8+δ). The momentum-dependent energy and linewidth of an A1 optical phonon were obtained. Based on these data as well as detailed knowledge of the electronic structure, we developed a scheme to determine the electron-phonon coupling (EPC) matrix element related to a specific phonon mode. Such an approach is general and applicable to elucidating the full structure of EPC in a system with anisotropic electronic structure. 相似文献
998.
Qinmin Guo Zhihui Qin Cunding Liu Kan Zang Yinghui Yu Gengyu Cao 《Surface science》2010,604(19-20):1820-1824
Bias-dependent features of the insulating NaCl layer grown on Cu(001) have been investigated by scanning tunneling microscopy/spectroscopy (STM/STS). The apparent layer thickness of the NaCl film is variable at bias voltages ranging from 2.8 to 3.2 V as well as from 4.0 to 5.0 V, and the Moiré pattern induced by NaCl–Cu lattice mismatch also shows bias dependence. The z–V (dz/dV–V) curves and dI/dV mapping measurements reveal that the resonant tunneling between the image potential states (IPSs) on Cu(001) and the Fermi level of the STM tip leads to drastic variations of these features. 相似文献
999.
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
1000.
The conversion of silver nanoparticle (NP) paste films into highly conductive films at low sintering temperature is an important requirement for the developing areas of additive fabrication and printed electronics. Ag NPs with a diameter of ∼10 nm were prepared via an improved chemical process to produce viscous paste with a high wt%. The paste consisted of as-prepared Ag NP and an organic vehicle of ethylcellulose that was deposited on glass and Si substrates using a contact lithographic technique. The morphology and conductivity of the imprinted paste film were measured as a function of sintering temperature, sintering time and the percentage ratio of Ag NP and ethylcellulose. The morphology and conductivity were examined using scanning electron microscopy (SEM) and a two-point probe electrical conductivity measurement. The results show that the imprinted films were efficiently converted into conducting states when exposed to sintering temperature in the range of 200-240 °C, this temperature is lower than the previously reported values for Ag paste. 相似文献