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91.
Xian-Zhu FuXiao-Xiong Luo Jing-Li Luo Karl T. ChuangAlan R. Sanger Andrzej Krzywicki 《Journal of power sources》2011,196(3):1036-1041
Ethane and electrical power are co-generated in proton ceramic fuel cell reactors having Cr2O3 nanoparticles as anode catalyst, BaCe0.8Y0.15Nd0.05O3−δ (BCYN) perovskite oxide as proton conducting ceramic electrolyte, and Pt as cathode catalyst. Cr2O3 nanoparticles are synthesized by a combustion method. BaCe0.8Y0.15Nd0.05O3−δ (BCYN) perovskite oxides are obtained using a solid state reaction. The power density increases from 51 mW cm−2 to 118 mW cm−2 and the ethylene yield increases from about 8% to 31% when the operating temperature of the solid oxide fuel cell reactor increases from 650 °C to 750 °C. The fuel cell reactor and process are stable at 700 °C for at least 48 h. Cr2O3 anode catalyst exhibits much better coke resistance than Pt and Ni catalysts in ethane fuel atmosphere at 700 °C. 相似文献
92.
The oxidation of ethanol was studied in low-pressure, premixed flat flames using molecular beam mass spectrometry (MBMS) in combination with electron impact ionization (EI) and resonance-enhanced multiphoton ionization (REMPI). Flame temperature profiles were measured by laser-induced fluorescence (LIF) of seeded NO. Two ethanol/oxygen/argon flames with stoichiometries of ?=1.00 and ?=2.57 were investigated at 50 mbar by EI-MBMS. Profiles of a variety of stable and radical species were measured as a function of height above the burner. The benzene profile in the fuel-rich ethanol flame was obtained by REMPI-MBMS. The same technique was used to determine the dependence of the benzene concentration on the ethanol/propene ratio in low-pressure flames with blended fuels (propene/ethanol/oxygen/argon). The C/O ratio of all blends was kept constant at C/O=0.773 or C/O=0.600. Ethanol addition ranged from 0 to 15% for flames with C/O=0.773, and from 0 to 100% for flames with C/O=0.600. In both data sets, a decrease of the benzene concentration with increasing ethanol percentage was observed. Qualitative information on some other aromatic species with higher mass was also obtained. 相似文献
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本文采用溶胶-凝胶法制备了不同含量的Y2O3掺杂的CeO2粉体,并在4mol%Y2O3—CeO2粉体中掺入Al2O3,研究了各样品的烧结性能和电性能。结果表明:适量的掺杂Y2O3能提高氧化铈的密度,但Y2O3含量超过4%mol后密度下降。一定量的Al2O3也能提高材料的烧结密度。随着Y2O3含量的增大,CeO2的电导先增大后减小,而掺入Al2O3对材料的电导不利。 相似文献
96.
Wei-na Miao Xi-feng Li Qun Zhang Li Huang Zhuang-jian Zhang Li Zhang Xue-jian Yan 《Thin solid films》2006,500(1-2):70-73
An amorphous transparent conductive oxide thin film of molybdenum-doped indium oxide (IMO) was prepared by reactive direct current magnetron sputtering at room temperature. The films formed on glass microscope slides show good electrical and optical properties: the low resistivity of 5.9 × 10− 4 Ω cm, the carrier concentration of 5.2 × 1020 cm− 3, the carrier mobility of 20.2 cm2 V− 1 s− 1, and an average visible transmittance of about 90.1%. The investigation reveals that oxygen content influences greatly the carrier concentration and then the photoelectrical properties of the films. Atomic force microscope evaluation shows that the IMO film with uniform particle size and smooth surface in terms of root mean square of 0.8 nm was obtained. 相似文献
97.
M. Stankova X. Vilanova E. Llobet J. Calderer M. Vinaixa I. Grcia C. Can X. Correig 《Thin solid films》2006,500(1-2):302-308
Thin films of either pure or doped tungsten oxide were grown by radiofrequency (rf) sputtering onto silicon micromachined substrates. Up to 7 different dopant materials (noble metals or metal oxides) were deposited by rf sputtering or by evaporation onto the tungsten oxide films. The responsiveness of the resulting micromachined sensors towards sulfur dioxide and hydrogen sulfide was studied. Other pollutants in CO2 such as ethylene and methane were also tested. It was found that Au-doped tungsten oxide sensors were highly sensitive to H2S, poorly sensitive to SO2 and almost insensitive to hydrocarbons. On the other hand, Pt-doped tungsten oxide was highly sensitive to SO2, poorly responsive to H2S and nearly insensitive to hydrocarbons. By applying a principal component analysis (PCA), we show that it would be possible to selectively detect traces of H2S and SO2 in a CO2 stream using doped WO3 microsensors. These sensors could be used in a low-cost analyzer of beverage-grade CO2. 相似文献
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Several substituted titanates of formula Li4−xMgxTi5−xVxO12 (0 ≤ x ≤ 1) were synthesized (and investigated) as anode materials in rechargeable lithium batteries. Five samples labeled as S1–S5 were calcined (fired) at 900 °C for 10 h in air, and slowly cooled to room temperature in a tube furnace. The structural properties of the synthesized products have been investigated by X-ray diffraction (XRD), scanning electron microscope (SEM) and Fourier transmission infrared (FTIR). XRD explained that the crystal structures of all samples were monoclinic while S1 and S3 were hexagonal. The morphology of the crystal of S1 was spherical while the other samples were prismatic in shape. SEM investigations explained that S4 had larger grain size diameter of 15–16 μm in comparison with the other samples. S4 sample had the highest conductivity 2.452 × 10−4 S cm−1. At a voltage plateau located at about 1.55 V (vs. Li +), S4 cell exhibited an initial specific discharge capacity of 198 mAh g−1. The results of cyclic voltammetry for Li4−xMgxTi5−xVxO12 showed that the electrochemical reaction was based on Ti4+/Ti3+ redox couple at potential range from 1.5 to 1.7 V. There is a pair of reversible redox peaks corresponding to the process of Li+ intercalation and de-intercalation in the Li–Ti–O oxides. 相似文献
100.
Visible-light-driven nitrogen-doped TiO2 was synthesized using a novel nitrogen-ion donor of hydrazine hydrate. Low-concentration (0.2 at%) nitrogen species and Ti3+ were detected in the TiO2-based photocatalyst by X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) spectroscopy. The trace amount of Ti–N would contribute to the minor band-gap narrowing of about 0.02 eV. Those nitrogen-containing species, especially the NO22− species, form surface states, which make the catalysts possible to degrade 4-chlorophenol (4-CP) under visible irradiation (λ>400 nm). Moreover, Ti3+ species induce oxygen vacancy states between the valence and the conduction bands, which would also contribute to the visible response. The photocatalytic activity of the nitrogen-doped TiO2 catalyst was thought to be the synergistic effect of nitrogen and Ti3+ species. The catalysts showed higher photocatalytic activity for degradation of 4-CP than pure TiO2 under not only visible but also UV irradiation. The visible response and the higher UV activity of the nitrogen-doped TiO2 make it possible to utilize solar energy efficiently to execute photocatalysis processes. 相似文献