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71.
L. C. Feng W. Z. Shao L. Zhen N. Xie V. V. Ivanov 《International Journal of Applied Ceramic Technology》2007,4(5):453-462
Cu2 O/ x Cu ( x =0–25 wt%) cermets were evaluated as a novel partially inert anode for aluminum (Al) production. The physical and mechanical properties, including the compressive strength, flexural strength, thermal expansion coefficient, thermal conductivity, and dc electrical conductivity were tested at room temperature and at temperatures up to 950°C. The coefficient of thermal expansion, compressive strength, flexural strength, thermal conductivity, and electrical conductivity of Cu2 O/Cu cermets increased with increasing Cu content. High-temperature electrical conductivity measurements showed that with increasing temperature, the electrical conductivity increased when the Cu content was below the percolation threshold, while it decreased when the Cu content was above the percolation threshold. A relatively stable CuAlO2 layer formed on the cermet surface during electrochemical testing, and the corrosion rate of this anode was estimated to be about 1.8–1.9 cm/year in Al production. 相似文献
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云母填料尺寸效应对水在环氧涂层中扩散行为的影响 总被引:2,自引:0,他引:2
以3种不同尺寸(124μm、38μm和19μm)的片状云母粉为填料,应用质量法和电化学阻抗法(EIS)研究云母填料尺寸效应对水在环氧涂层中的扩散行为的影响。结果表明在几种涂层中,水的扩散总是分为两个阶段:扩散初期阶段和平衡扩散阶段。浸泡初期水在涂层中的扩散行为除了124μm云母环氧涂层基本符合理想菲克扩散行为外,38μm云母环氧涂层和19μm云母环氧涂层均符合理想的菲克扩散定律,即涂层的吸水与浸泡时间的1/2次方成正比。但是水在几种涂层中的扩散系数却各不相同,其中38μm云母环氧涂层的扩散系数最小。 相似文献
75.
Terpolymers based on N‐isopropylacrylamide, sodium 2‐acrylamido‐2‐methyl‐propanesulfonate, and N‐tert‐butylacrylamide were synthesized by free‐radical copolymerization with 2,2′‐azobisisobutyronitrile as an initiator. The lower critical solution temperatures (LCSTs) of the linear polymer aqueous solutions were determined by the measurement of the transmittance on UV at different temperatures. The influence of the polymer concentration, polymer composition, and ionic strength on the LCSTs of the linear polymers was investigated. The LCST decreased with increases in the hydrophobic monomer N‐tert‐butylacrylamide, polymer concentration, and ionic strength. The phase transition became sharp when the polymer concentration and ionic strength increased. Meanwhile, the crosslinked hydrogels were prepared with the same recipe used for the linear terpolymers, but a crosslinker was added to the reaction system. The swelling ratios of the hydrogels at various temperatures and salt solutions were determined. The hydrogels possessed both high swelling ratios and thermosensitivity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
76.
核壳型乳液聚合研究进展 总被引:3,自引:0,他引:3
综述了近年来核/壳结构聚合物乳液的聚合工艺、性能及核/壳结构的表征方法进行,讨论了影响核/壳结构聚合物乳胶粒子形态的各种因素。 相似文献
77.
本文介绍了一个微机上运行的注塑模CAD系统,此系统主要解决了四个难点,浇注系统设计,冷却系统分析,型腔,型芯的曲面造型设计,装配图和零件工作图的设计绘制,经厂家实际运用证明,该系统使用方便,结果正确,能提高设计效率,降低生产成本。 相似文献
78.
Weizeng Shao Susanne Lehner Changlong Guan 《International journal of remote sensing》2014,35(11-12):4046-4063
In this article, the polarization ratio (PR) of TerraSAR-X (TS-X) vertical–vertical (VV) and horizontal–horizontal (HH) polarization data acquired over the ocean is investigated. Similar to the PR of C-band synthetic aperture radar (SAR), the PR of X-band SAR data also shows significant dependence on incidence angle. The normalized radar cross-section (NRCS) in VV polarization data is generally larger than that in HH polarization for incidence angles above 23°. Based on the analysis, two PR models proposed for C-band SAR were retuned using TS-X dual-polarization data. A new PR model, called X-PR hereafter, is proposed as well to convert the NRCS of TS-X in HH polarization to that in VV polarization. By using the developed geophysical model functions of XMOD1 and XMOD2 and the tuned PR models, the sea surface field is retrieved from the TS-X data in HH polarization. The comparisons with in situ buoy measurements show that the combination of XMOD2 and X-PR models yields a good retrieval with a root mean square error (RMSE) of 2.03 m s–1 and scatter index (SI) of 22.4%. A further comparison with a high-resolution analysis wind model in the North Sea is also presented, which shows better agreement with RMSE of 1.76 m s–1 and SI of 20.3%. We also find that the difference between the fitting of the X-PR model and the PR derived from TS-X dual-polarization data is close to a constant. By adding the constant to the X-PR model, the accuracy of HH polarization sea surface wind speed is further improved with the bias reduced by 0.3 m s–1. A case acquired at the offshore wind farm in the East China Sea further demonstrates that the improvement tends to be more effective for incidence angles above 40°. 相似文献
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80.
X.Y.?Wang J.M.?WangEmail author H.B.?Shao J.Q.?Zhang C.N.?Cao 《Journal of Applied Electrochemistry》2005,35(2):213-216
The corrosion behavior of pure aluminum in inhibited and uninhibited 4 MKOH was investigated by means of hydrogen collection, polarization curve measurement and electrochemical impedance spectroscopy (EIS). The results showed that the corrosion of pure aluminum was greatly inhibited by the addition of ZnO and dimethyl amine epoxy propane (designated as DE). EIS and EDAX analyses revealed that ZnO produces its effect by depositing on the aluminum surface, which increases the overpotential of hydrogen evolution. It was also found that the addition of DE could greatly improve the deposition of zinc layers. 相似文献