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101.
102.
合成氨生产装置中热钾碱脱碳系统的钢铁腐蚀和防护是关系能否安全稳定运行的关键,只要认真做好制造的热处理,生产前的钝化,生产中的保护就能达到预期目的。 相似文献
103.
Teng-Yu Wang Cheng-Chi Liu Chien-Hsiung Hon Chen-Hsun Du Chung-Yuan Kung 《能源与动力工程:英文版》2013,(8):1505-1510
The surface of silicon was passivated by A1203 and acidify using nitric acid with SiOx as the bi-layer, it was expected that hydrogen bonding reduce interface states and negative field effect which yields maximum passivation. By optimizing the thickness of passivation layer and annealing condition, the minority carrier lifetime of p-type single crystalline Czochralski wafer could be improved from 10 μs to 190 μs. The formation and variation of hillock defect on passivation layer was founded to be affected by the thermal annealing temperature. For the purpose of obtaining high minority carrier lifetime and low hillock defect density simultaneously, using a lower heating and cooling speed in thermal annealing process is suggested. 相似文献
104.
D. Tsoutsou Y. PanayiotatosS. Galata A. SotiropoulosG. Mavrou E. GoliasA. Dimoulas 《Microelectronic Engineering》2011,88(4):407-410
The molecular and atomic oxidation of molecular beam deposited Se passivating layers on Ge substrates was in situ investigated by X-ray photoelectron spectroscopy. It turns out that while Se is efficient in suppressing Ge oxidation upon molecular oxygen exposure, an extra thin Al layer is needed to protect the Ge surface from highly reactive atomic oxygen radicals. Electrical measurements performed on the Al-covered surfaces reveal that Se is beneficial in reducing the interface state density. 相似文献
105.
A. M. Barnett J. A. Rand R. B. Hall J. C. Bisaillon E. J. DelleDonne B. W. Feyock D. H. Ford A. E. Ingram M. G. Mauk J. P. Yaskoff P. E. Sims 《Solar Energy Materials & Solar Cells》2001,66(1-4)
Solar cells utilizing thin-film polycrystalline silicon can achieve photovoltaic power conversion efficiencies greater than 19%. These high efficiencies are a result of light trapping and back surface passivation. Optimum silicon thickness, for devices employing such technology, has been determined to be 20 μm (Blakers et al., Appl. Phys. Lett. 60 (1992) 2572) to 35 μm (Rand et al., Proceedings of the IEEE Photovoltaic Specialist Conference, Orlando, FL, May 1990, p. 263). Low cost is achieved by minimizing the required amount of silicon feedstock per watt of power output. The use of an electrically insulating supporting substrate allows for monolithic, series connected sub-modules. A solar cell with a 20 μm thick polycrystalline Si-layer on a ceramic substrate, utilizing both light trapping and back-surface passivation, was fabricated and characterized. A short-circuit current of 25.8 mA/cm2 was measured and verified by the National Renewable Energy Laboratory (NREL). 相似文献
106.
The composition of passivating products on galvanized steel reinforcement in concrete during carbonation was studied. Cube‐shaped concrete specimens were manufactured with Portland 52.5 R cement and reinforced with hot‐dip galvanized steel sheets obtained from pure Zn and Zn? Sn? Bi? Ni alloy bath. The concrete specimens were exposed to air curing for 28 days and then to the carbonation chamber. Corrosion rate and potential measurements were performed both during the curing in air and exposure in a carbonation chamber. At defined periods of time, some concrete specimens were broken and the galvanized steel sheets were submitted to XRD, SEM observations and EDX analysis. The growth of the passivation products was evaluated by integrating the diffraction peaks. XRD analysis and SEM observations show that the layer of calcium hydroxyzincate (CaHZn), formed on the galvanized sheets during the air curing, is destroyed by the concrete carbonation process. However, potential measurements indicate that the galvanized steel always remains in the passive state. X‐ray diffractometry was not able to identify the new passivating product; EDX maps suggest the presence of zinc carbonates. 相似文献
107.
电镀锌基合金工艺的发展及应用 总被引:11,自引:0,他引:11
综述了锌与铁族金属形成的二元合金铁电镀艺及应用情况,其中主要对锌-镍、锌-钴、锌-铁合金电镀工艺方法和特点作了较详细的论述。 相似文献
108.
介绍了氟气的性质,提出了如何正确选择耐氟腐蚀和氧化的各种金属及非金属,介绍了氟气对人体的毒害特点及各种安全数据。 相似文献
109.
110.
介绍了不同处理方式对黄铜制品经二步钝化法处理后形成钝化膜外观,色泽及结构的影响,并通过扫描电镜对钝化膜结构进行了表征,试验结果表明,黄铜制品在酸蚀后经1号钝化液钝化15s,2号钝化液钝化30s所形成的钝化膜结构致密、性能优良。 相似文献