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101.
Hyunwoong Seo Minkyu Son Jitae Hong Dong-Yoon Lee Tae-Pung An Hyunju Kim Hee-Je Kim 《Solar Energy》2009,83(12):2217-2222
Large dye-sensitized solar cells (DSCs) are usually fabricated as module types instead of single cell types, because the overall efficiency of an area-expanded single DSC is decreased by its large surface resistances and low fill factor (FF). The general DSC module designs are the parallel grid, series interconnect, and series monolithic types. The W-series interconnect type of module has some advantages, such as its easy fabrication and simple structure. Moreover, it also avoids the reduction in the FF. However, it has an efficiency imbalance between the single cells, because of the discrepancy in their luminous intensity. Therefore, the fabrication of the W-series interconnect type of module will be cost-effective only if the problem of its efficiency imbalance is solved. In this study, the thickness of the Pt layer, which has a very high reflection rate, and that of the electrolyte layer are minimized and the transmitted light is reflected by a metallic thin film in order to increase the number of photons absorbed by the dye molecules in the module. As a result, the performance of the efficiency-balanced W-module is improved by approximately 1% as compared to that of the conventional module. 相似文献
102.
Abstracts are not published in this journal
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
103.
Effect of chromium on the phase evolution and microstructure of ZnO doped with bismuth and antimony 总被引:2,自引:0,他引:2
Crystalline phase formation and microstructure of ZnO varistors with a basic composition ZnO–Bi2O3–Sb2O3 were examined. Addition of chromium oxide to this basic varistor resulted in an α-spinel (α-Zn7Sb2O12) phase dissolving a significant amount of Cr, while the β-spinel did not. β-spinel transformed to pyrochlore during cooling,
whereas α-spinel hardly transformed to pyrochlore irrespective of the cooling conditions. When Sb2O3 was completely replaced by Cr2O3, ZnCr2O4 was formed instead of spinel. α-spinel particles were 1–2 μm in size and intra- as well as intergranular. ZnCr2O4 particles, smaller than 1 μm in size, however, were present as aggregates in the bismuth-rich matrix phase at the grain boundaries.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
104.
CHANG JUNG KIM DAE SUNG YOON ZHONG-TAO JIANG KWANGSOO NO 《Journal of Materials Science》1997,32(5):1213-1219
The crystal orientations of lead zirconate titanate (PZT) thin films have been investigated by using various drying temperatures
in the sol–gel process. The films were dried at different temperatures between 310 and 350°C for pyrolysis and then were heat
treated at 650°C using rapid thermal annealing (RTA). TG/DTA and FTIR spectroscopy were used to detect the remnants of organic
materials in the thin films prior to the final heat treatment. In order to examine the relationship between the film orientation
and the remaining organic materials for the prior and final heat treatment, the films were fabricated with different coating
cycles and dried for different holding times and then annealed at 650°C. The preferred orientations were investigated using
X-ray diffraction.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
105.
To solve information asymmetry problem on online auction, this study suggests and validates a forecasting model of winning bid prices. Especially, it explores the usability of data mining approaches, such as neural network and Bayesian network in building a forecasting model. This research empirically shows that, in forecasting winning bid prices on online auction, data mining techniques have showed better performance than traditional statistical analysis, such as logistic regression and multivariate regression. 相似文献
106.
107.
108.
109.
Al-doped ZnO (AZO) is considered as an alternative to transparent conductive oxide materials. Patterning and achieving a stable surface are important challenges in the development and optimization of dry etching processes, which must be overcome for the application of AZO in various devices. Therefore, in this study, the etch rate and surface properties of an AZO thin film after plasma etching using the adaptive coupled plasma system were investigated. The fastest etch rate was achieved with a CF4/Ar ratio of 50:50 sccm. Regardless of the ratio of CF4 to Ar, the transmittance of the film in the visible region exceeded 80%. X-ray photoelectron spectroscopy analysis of the AZO thin film confirmed that metal-F bonding persists on the surface after plasma etching. It was also shown that F eliminates O vacancies. Consequently, the work function and bandgap energy increased as the ratio of CF4 increased. This study not only provides information on the effect of plasma on AZO thin film, but identifies the cause of changes in the device characteristics during device fabrication. 相似文献
110.
Decomposed products of 2-tert-butylhydroquinone (TBHQ) at frying temperature in model system were identified and characterized. An attempt was made to determine the functions of the decomposed compounds in foods using model system. Tert-butylbenzoquinone (TBBQ) was identified as the primary and major oxidation product of TBHQ. Interconversion between TBHQ and TBBQ was the most important role in antioxidant effectiveness and carry-through effect of TBHQ. Several types of dimers by ether linkage resulting from thermolysis at frying temperature were identified. In addition, significant reactivity of a phenolic antioxidant with the functional carboxyl group of a fatty acid, which might lower antioxidant effectiveness, was determined using a simple model system. 相似文献