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We have obtained novel photosensitive materials containing a semiconductor photocatalyst and a dye sensitizer. We have studied the activity of the latter in the reaction of photoreduction of methylene blue, and we consider possible mechanisms for the photocatalytic effect. 相似文献
74.
Adel Attia Markéta Zukalová Jiří Rathouský Arnošt Zukal Ladislav Kavan 《Journal of Solid State Electrochemistry》2005,9(3):138-145
A mesoporous electrode material whose structure is composed of anatase nanocrystals stabilized by alumina is reported. Powder X-ray diffraction shows the anatase phase only, but micro-Raman spectroscopy shows that the materials have a core-shell morphology with grains of bulk anatase covered by a thin rutile layer on the surface. This structure is unique when compared to analogous materials stabilized by zirconia (PNNL-1). Nitrogen adsorption isotherms demonstrate a monotonous increase in surface area and mesopore volume with increasing Al content. Thin film electrodes from these materials were characterized by lithium insertion electrochemistry. Cyclic voltammograms exhibit significant differences in Li accommodation in Al-free and Al-stabilized materials. 相似文献
75.
Liu B. Thomas P. S. Ray A. S. Williams R. P. 《Journal of Thermal Analysis and Calorimetry》2004,76(1):115-122
The effect of sampling conditions on the decomposition of electrolytic manganese dioxide using thermal methods is reported.
Significant differences were observed in the mechanism of the decomposition by simply changing the reaction environment from
a closed pan to an open pan configuration. The purge gas atmosphere was also observed to influence the decomposition mechanism.
As a product of the decomposition is oxygen, the change in the mechanism observed between the experimental conditions may
be explained in terms of the ease of removal of oxygen from the reaction site.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
76.
Djaoued Y. Badilescu Simona Ashrit P.V. Bersani D. Lottici P.P. Brüning R. 《Journal of Sol-Gel Science and Technology》2002,24(3):247-254
TiO2 nanocrystalline thin films with varying degree of porosity have been prepared using a low temperature method. TiO2 films of the anatase form have been obtained by using a polyethylene glycol (PEG) modified sol-gel method. Densification and crystallization of the films was found to result from the thermal treatment of the dip coated films in boiling water. The films have been characterized by Raman, XRD, FTIR, AFM and optical methods. Highly transparent films with transmission in excess of 85% and porosity as high as 58% are formed predominantly of anatase crystallites of dimensions of the order of 5 nm. Initial results on lithium intercalation into these films resulting in an efficient optical modulation in the visible and near infrared regions demonstrate a good potential of these films for electrochromic applications. 相似文献
77.
The effects of lithium oxide dopants (0.5–0.8 at. % Li) on the electrophysical and sorption properties of ZnO were studied in the temperature range from 150 °C to 410 °C. The introduction of lithium increases the activation energy of the conductivity of ZnO, decreases its conductivity, and increases the amount of S02 sorbed. Two forms of chemisorbed SO2 (donor and acceptor) are observed on the surface.Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 5, pp. 1096–1100, May, 1996. 相似文献
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79.
采用光学显微镜、扫描电和力学性能测试设备,研究了在IMI829和Ti-14Al-21Nb合金中添加Y,对合金显微组织遥影响。结果表明,在IMI829和Ti-14Al-21Nb合金中添加Y,可以细化这两种合金的组织和晶粒,使IMI829-0.2Y合金获得良好的室温力学性能和550℃蠕变性能,wgkqTi-14Al-21Nb-0.1Y合金的高温力学性能得到改善。 相似文献
80.
Cycloaddition of carbon dioxdie and propylene oxide to propylene carbonate catalyzed by tetra-tert-butyl metal phthalocyanine in the presence of tributylamine(TBA) shows higher yield than catalyzed by unsubstituted metal phthalocyanine.Comparing different catalysts of diverse metals,(t-Bu)4PcMg is more active than (t-Bu)PcFe ,But(t-Bu)4PcCo and (t-Bu)4PcNi only have low catalytic activities towards the reaction.Moreover,the yield will increase as the temperature increases. 相似文献