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91.
以《无机物热力学数据库》为依据,给出了Pb、Sn、In、Ga、Ce 等化合物的△G°~T二项式和关系图。Sn及常量配比的Pb-Sn合金,经常温大气腐蚀、155℃干热大气腐蚀或水蒸汽腐蚀,表面腐蚀层用X光光电子能谱分析(XPS或ESCA)确定主要是SnO2(含有极少量的Pb3O4),此结果与热力学分析结果一致。Pb经155℃ 干热大气腐蚀,表面腐蚀区主要是Pb3O4。由热力学分析,提出了可能成为抗氧化Pb-Sn 焊料的掺杂元素。 相似文献
92.
P. Grrn M. Sander J. Meyer M. Krger E. Becker H.‐H. Johannes W. Kowalsky T. Riedl 《Advanced materials (Deerfield Beach, Fla.)》2006,18(6)
The first fully transparent organic light‐emitting diode (OLED) pixels, fabricated by integrating transparent OLEDs on top of transparent thin‐film transistors (TTFTs), are demonstrated on p. 738 by Riedl and co‐workers, and shown schematically on the inside cover. With an average transmittance of more than 70 % in the visible part of the spectrum (400–750 nm), the presented active pixels pave the way to the realization of fully transparent active matrix displays. 相似文献
93.
含铟锡烟尘硫酸氧压浸出提铟试验 总被引:5,自引:1,他引:5
对含铟锡烟尘进行硫酸氧压浸出提铟试验。考察了各种因素对铟浸出效果的影响。结果表明,含铟物料在液固比4∶1,硫酸初始浓度150g/L,温度150℃,氧分压0.7MPa,时间150min的条件下进行氧压浸出,可获得93.66%的铟浸出率。 相似文献
94.
Analysis of Volatile Bread Aroma for Evaluation of Bread Freshness Using an Electronic Nose (E-Nose)
This paper presents the use of a tin-oxide sensor array and self-organized map (SOM)-based E-nose for analysis of volatile bread aroma and explores its ability to cluster bread odor data according to the freshness of bread. A low cost tin-oxide sensor array based electronic nose system has been used for the classification of state of freshness of bread. The sensor data was acquired for a period of 3 weeks, and an unsupervised self-organizing map (SOM) model was trained using this data to correlate the sensor response to classify the bread as fresh and stale. A comparative evaluation of 3 week' of bread data was carried out using the SOM. The results suggest that the system developed is able to predict the state of bread as fresh and stale up to 98% accuracy if the test bread data sets are of the same week. The classification accuracy reduces to 75-85% if test bread data sets are from different weeks. The model is also applied on three different brands of bread and similar classification results are obtained. 相似文献
95.
研究了锑、锌、锰等合金元素对锑青铜的组织和性能的影响,经过大量试验,研制出具有良好综合性能的新型锑青铜材料,是目前替代锡青铜材料的理想材料。 相似文献
96.
Tin oxide (SnO2) nanocrystals of a few nanometers are of great interest for electronic applications. Here we present a mini-arc plasma method
to produce aerosol tin oxide nanocrystals at atmospheric pressure. The product SnO2 nanocrystals are then assembled onto the external surface of carbon nanotubes (CNTs) to form hybrid SnO2–CNT structures. The absorption properties of both the SnO2 nanocrystals and the SnO2–CNT hybrid structures have been characterized. Quantum size effects have been observed for as-produced SnO2 nanocrystals. The intrinsic nanoparticle size selection during the assembly process results in a blue shift of the absorption
spectrum for hybrid nanostructures. 相似文献
97.
一种小断纬是出现在织口到胸梁的布面上,另一种小断纬是出现在导布辊引出的布面上.这两种小断纬都是全幅纬向分散性的无规律的、像边撑疵一样的小断纬,而且经后整理后小断纬增多.经过分析,认为第一种小断纬是因单纱强力不同的漂白纱混批造成的,第二种小断纬则是刺毛铁皮刺高所引起.详细介绍了相应的预防措施. 相似文献
98.
Following the procedure by Sawada et al. (Thin Solid Films 409 (2002) 46), high-quality SnO2:F films were grown on glass substrates at relatively low temperatures of 325–340°C by intermittent spray pyrolysis deposition using a perfume atomizer for cosmetics use. Even though the substrate temperature is low, as-deposited films show a high optical transmittance of 92% in the visible range, a low electric resistivity of 5.8×10−4 Ω cm and a high Hall mobility of 28 cm2/V s. The F/Sn atomic ratio (0.0074) in the films is low in comparison with the value (0.5) in the sprayed solution. The carrier density in the film is approximately equal to the F-ion density, suggesting that most of the F-ions effectively function as active dopants. Films’ transmittance and resistivity show little change after a 450°C 60 min heat treatment in the atmosphere, evidencing a high heat resistance. The SnO2:F films obtained in this work remove the difficulty to improve the figure of merit at low synthesis temperatures. 相似文献
99.
The physical bases of a X radiation sampling technique are investigated.Three technical problems of unevenness,matrix and heterogeneous mineralization effects,are considered and successfully resolved.This new technique was appled to three sites of Au,Sn and Cu deposits(representing higher,medial and lower atomic number minerals)in different exploration stages in China and satisfactory results are obtained. 相似文献
100.
Tin oxide nanophases or nanoparticles were synthesized under conventional- and microwave-hydrothermal conditions and characterized by powder X-ray diffraction, BET surface area determination as well as transmission electron microscopy. The use of microwave-hydrothermal (M-H) process led to higher yields in shorter time compared to the conventional-hydrothermal (C-H) process because of increased reaction rates in the former. 相似文献