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91.
Geiler AL Yang A Zuo X Yoon SD Chen Y Harris VG Vittoria C 《Physical review letters》2008,101(6):067201
Using a novel alternating target laser ablation deposition technique, Mn cations were placed in specific interstitial sites of BaFe12O19 thin films as opposed to being distributed throughout the unit cell as in conventional bulk materials. The distribution of Mn cations has been confirmed experimentally and predicted theoretically. As a result of site selection, the saturation magnetization increased 12%-22%, and the Néel temperature increased by 40-60 K compared to bulk materials. This technique implies a new methodology to design and process a new generation of ferrite, oxide, and alloy materials. 相似文献
92.
Dae Seung Cho 《Applied Acoustics》2008,69(11):1120-1128
A highway traffic noise prediction model has been developed for environmental assessment in South Korea. The model is based on an outdoor sound propagation method and is fully compliant with ISO 9613 and the sound power level (PWL) estimation for a road segment, as suggested in the ASJ Model-1998 that is based on PWLs. Due to that model’s selection of two pavement types, such as asphalt or concrete pavement, an unacceptable traffic noise prediction is made in cases where the road surface is different from that on which the model is based. In order to address this problem, several road surface types are categorized, and the PWL of each surface type is determined and modeled by measuring the noise levels obtained from newly developed methods. An evaluation of the traffic noise prediction model using field measurements finds good agreement between predicted and measured noise levels. 相似文献
93.
Hans M. Christen Dae Ho Kim Christopher M. Rouleau 《Applied Physics A: Materials Science & Processing》2008,93(3):807-811
Recent advances in film synthesis have made it possible to investigate the properties of well-controlled interfaces in perovskite
metal-oxides. A review of published experimental data and computational results indicate that so far most interfaces that
have been analyzed in ferroelectric materials—while necessary to impose large lattice strain on the polar material—contribute
little to the ferroelectricity and may instead be detrimental to the desired properties. In contrast, a very different situation
arises at interfaces that show changes in the electronic configuration as a consequence of a compositional discontinuity.
Data is shown for LaMnO3/SrTiO3 superlattices as an example of electronic effects that produce enhanced properties, further illustrating the richness of
interfacial properties that can be obtained at interfaces (as shown in numerous published results for different but related
interfaces). 相似文献
94.
Fine-sized ZnO–B2O3–CaO–Na2O–P2O5 glass powders with spherical shape were directly prepared by high temperature spray pyrolysis. The ZnO–B2O3–CaO–Na2O–P2O5 powders prepared by spray pyrolysis at temperatures above 1200 °C had broad peaks at around 30° in the XRD patterns. The glass transition temperatures (Tg) of the glass powders obtained by spray pyrolysis at preparation temperatures between 900 °C and 1400 °C were near 480 °C regardless of the preparation temperatures. The dielectric layers formed from the glass powders prepared by spray pyrolysis at preparation temperatures above 1300 °C had clean surface and dense inner structure at the firing temperature of 580 °C. The transmittance of the dielectric layer formed from the glass powders obtained by spray pyrolysis at preparation temperature of 1400 °C was 90% at the firing temperature of 580 °C, in which the thickness of the dielectric layer was 13 μm. The UV cutoff edges gradually shift towards longer wavelength with increasing the preparation temperature of glass powders and the firing temperature of dielectric layers. 相似文献
95.
96.
Effect of branched alkyl side chains on the performance of thin‐film transistors and photovoltaic cells fabricated with isoindigo‐based conjugated polymers
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Gi Eun Park Jicheol Shin Dae Hee Lee Min Ju Cho Dong Hoon Choi 《Journal of polymer science. Part A, Polymer chemistry》2015,53(10):1226-1234
New isoindigo and di(thienyl)ethylene‐containing π‐extended conjugated polymers with different branched side chains were synthesized to investigate their physical properties and device performance in thin‐film transistors and photovoltaic cells. 11‐Butyltricosane (S3) and 11‐heptyltricosane (S6) groups were used as side‐chain moieties tethered to isoindigo units. The linking groups between the polymer backbone and bifurcation point in the branched side chain differ in the two polymers (i.e., PIDTE‐S3 and PIDTE‐S6 ). The polymers bearing S6 side chains showed much better charge transport behavior than those with S3 side chains. Thermally annealed PIDTE‐S6 film exhibited an outstanding hole mobility of 4.07 cm2 V?1 s?1 under ambient conditions. Furthermore, bulk heterojunction organic photovoltaic cells made from a blend film of PIDTE‐S3 and (6,6)‐phenyl C61‐butyric acid methyl ester demonstrated promising device performance with a power conversion efficiency in the range of 4.9–5.0%. © 2015 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 2015 , 53, 1226–1234 相似文献
97.
High‐performance alternating current electroluminescent layers solution blended with mechanically and electrically robust nonradiating polymers
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98.
Chanho Pak Seung Woo Lee Chaekyung Baik Bong Ho Lee Dae Jong You Eunyoung You 《中国化学快报》2019,30(6):1186-1189
New approach for the reversal tolerant anode for polymer electrolyte membrane fuel cell is suggested by using the multifunctional IrRu alloy catalyst having concurrent superior activities towards hydrogen oxidation reaction and oxygen evolution reaction to mitigate the degradation of anode under the fuel starvation condition. 相似文献
99.
100.