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481.
Recently,surface-disordered or non-stoichiometric TiO_2,such as blue TiO_2(B-TiO_2),has received much attention owing to its unique properties,such as structural disorder near the surface and the existence of Ti~(3+)ions and oxygen vacancies.Therefore,surface-disordered TiO_2has been applied for microwave absorption,photocatalysis,in photoelectrochemical sensors and rechargeable lithium-ion batteries.In this work B-TiO_2,a polymorph consisting of nanoparticles,nanotubes and nanosheets,was successfully synthesized and employed as a semiconductor layer in dye-sensitized solar cells(DSSCs)fabricated using a low-temperature heat treatment process(120°C).Based on the analyses of the experimental results regarding the structure and those from the characterization of B-TiO_2,and its application to DSSCs,it has been found that the B-TiO_2 material has an effect on electron-hole pair separation.The conversion efficiency of the B-TiO_2 DSSC(BTiO_2-DSSC)was 6.18%,whereas that of the TiO_2-P25 DSSC(P25-DSSC)was 3.61%,and that of the TiO_2 polymorph DSSC(PTiO_2-DSSC)which is the precursor of B-TiO_2 was 4.51%. 相似文献
482.
Soo-Young Lee 《Cellular and molecular life sciences : CMLS》1989,45(7):600-600
Science Policy News
The European Brain Research Program 1989–1990 of the European Science Foundation (ESF) 相似文献483.
The dye sensitized solar cell(DSSC), which converts solar light into electric energy, is expected to be a promising renewable energy source for today’s world. In this work, dye sensitized solar cells, one containing a single layer and one containing a double layer, were fabricated. In the double layer DSSC structure, the under-layer was TiO2-P25 film, and the top layer consisted of a mixture of TiO2-P25 and TiO2 nanotubes. The results indicated that the efficiency of the DSSC with the double layer structure was a significant improvement in comparison to the DSSC consisting of only a single film layer. The addition of TiO2-P25 in the top layer caused an improvement in the adsorption of dye molecules on the film rather than on the TiO2 nanotubes only. The presence of the TiO2 nanotubes together with TiO2-P25 in the top layer revealed the enhancement in harvesting the incident light and an improvement of electron transport through the film. 相似文献
484.
Amy J. C. Trappey Charles V. Trappey Sandy W. C. Chang W. T. Lee Tun Nien Hsu 《系统科学与系统工程学报(英文版)》2016,25(2):229-253
A global enterprise must continuously improve the efficiency of logistic operations between supply chain collaborators. Integrating logistic services, resources, and necessary information flows in the supply chain to ensure efficiency and efficacy is critically important to these companies. Global logistic service companies face challenges from their clients to provide logistic services that are cost effective, accurate, and seamlessly integrate material, information and cash flows. In this research, an improved framework for one-stop logistic services is systematically designed, analyzed, and evaluated. The one-stop logistic service framework, defined in four models, is developed to provide enterprises with integrated and comprehensive services within the global supply chain context. The levels of service importance are assessed using a four categories questionnaire. This research provides a case study of the implementation of one-stop logistic services in the distribution industry and demonstrates the framework operating under different demand conditions. Finally, system dynamics causal evaluation is used to evaluate the advantages of the logistic service framework. 相似文献
485.
Effect of SiO2 addition on the dielectric properties and microstructure of BaTiO3-based ceramics in reducing sintering
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Ying-chieh Lee 《矿物冶金与材料学报》2009,16(1):124-127
The effect of SiO2 doping on the sintering behavior, microstructure, and dielectric properties of BaTiO3-based ceramics has been investigated. Silica was added to the BaTiO3-based powder prepared by the solid state method with 0.075mol%, 0.15mol%, and 0.3mol%, respectively. The SiO2-doped BaTiO3-based ceramic with high density and uniform grain size were obtained, which were sintered in reducing atmosphere. A scanning electron microscope, X-ray diffraction, and LCR meter were used to determine the microstructure as well as the dielectric properties. SiO2 can form a liquid phase belonging to the ternary system of BaO-TiO2-SiO2, leading to the formation of BaTiO3 ceramics with high density at a lower sintering temperature. The SiO2-doped BaTiO3-based ceramics can be sintered to a theoretical density higher than 95% at 1220℃ with a soaking time of 2 h. The dielectric constants of the sample with 0.15mol% SiO2 addition sintered at 1220℃ is about 9000. Doping with a small amount of silica can improve the sintering and dielectric properties of BaTiO3-based ceramics. 相似文献
486.
487.
Sometimes a larger dataset needs to be reduced to just a few points, and it is desirable that these points be representative
of the whole dataset. If the future uses of these points are not fully specified in advance, standard decision-theoretic approaches
will not work. We present here methodology for choosing a small representative sample based on a mixture modeling approach. 相似文献
488.
采用非破坏性透地雷达,对台湾嘉义市水上乡地下污染情况施测,参考实地钻探报告,对污染范围进行描绘,经比对施测结果与钻探报告,透地雷达检测比水轻非水相液体(LNAPL)污染结果准确,污染范围判定吻合. 相似文献
489.
Ben-Chaung Wang Fang-Yi Chou Yung-Jaan Lee 《Systemic Practice and Action Research》2010,23(2):157-172
Chung-Sheng Community in Taoyuan City, Taiwan is a typical urban community. By adopting participatory action research, this study examines resident awareness regarding the feasibility of transforming Chung-Sheng Community into a sustainable community. Action research can help avoid constant “trial and error” in constructing sustainable communities and enhance process efficiency. Meanwhile, an active research approach can help communities better achieve sustainable development. Constructing a sustainable urban community requires energy, effective frameworks, and professional assistance. Achieving these requires a continuous and participatory action research process, and careful exploration of the awareness of community residents, which is the focus of this investigation. 相似文献
490.
Yung-Jaan Lee Ben-Chaung Wang Pin-Chu Chen 《Systemic Practice and Action Research》2013,26(3):239-256
A cultural living circle comprises a “living cultural space” with local characteristics established via interactions between resident daily behaviors and the surrounding environment. In studying the long-term promotion of a cultural living circle in Sanyi Woodcarving Village, Miaoli, Taiwan to explore the sustainable development of cultural living circle, the authors engaged in local community building to identify its dynamic composition through Action Research, and conducted a field study examining cultural living circles and main interaction networks through literature review and in-depth interviews. This study obtains three findings. First, cultural living circles are created through interactions among four main systems, educational, community, professional and administrative. Second, in the interaction network, a core “leading system” guides other “subservient systems” to establish a “core-satellite” model. Third, the role changing that occurs during cultural living circle development constructs a solid and flexible link that can realize sustainable development of cultural living circles. 相似文献