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21.
STS310S and SC-STS310S (simultaneously co-deposited chromium and aluminum onto 310S austenitic stainless steel substrate by pack-cementation process) were used as separator materials on the cathode side of a molten carbonate fuel cell. With the STS310S, corrosion proceeded via three steps; a formation step of unstable corrosion product, a protection step against corrosion until breakaway, and an advance step of corrosion after breakaway. The final corrosion product was LiFeO2 and the loss of mass was 6.5 mg/cm2 after a corrosion test of 480 hr at 650°C. The SC-STS310S showed more effective corrosion resistance, however, than did common STS310S. There was especially no corrosion loss on the SC-STS310S after the 480 hr corrosion test. It is anticipated that it will be very useful as an alternative separator on the cathode side off the MCFC in the future.  相似文献   
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The ability to manipulate the intracellular environment within living cells and to monitor the cytosolic chemical changes which occur during cell stimulation has lead to major advances in our understanding of how cells read and respond to their environment. Perhaps the most powerful suite of techniques for achieving these dual objectives is based on the use of light (photons). Because cells are 'transparent', light has been used to both interrogate and manipulate the chemistry inside living cells, exploiting technical advances in both the physical and biochemical sciences. However, cells are neither transparent nor homogeneous with respect to their optical properties. The interface between light and the living cell cytoplasm thus represent an important, yet largely ignored, interface. There has been no review of the optical properties of cytoplasm and little discussion about how the optical properties of living cytoplasm influence the outcome of such measurements and manipulations. In this short review, we discuss the importance of understanding the optical properties of cytoplasm for such techniques and how imperfections in experimental interpretation can arise.  相似文献   
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赵峰  秦锋 《计算机工程》2009,35(19):78-80
研究基于单元的孤立点检测算法,给出数据空间的单元格划分及数据对象分配算法。针对该算法中阈值M设置的不足,对算法进行改进并应用于纳税行为的分析。与其他孤立点检测算法对比的结果表明,该算法不仅能有效挖掘纳税行为中的孤立点,还能确定孤立点的位置,有利于对纳税行为的分析。  相似文献   
25.
A multicellular organism is shown to be a community of special self-regulated cells with rigid and flexible regulating links, and a long-term adaptive trend of its system reaction to environmental changes is due to changes in the consumer gradients of groups of cells functioning against the imbalance between synthesis and decay of microstructures. __________ Translated from Kibernetika i Sistemnyi Analiz, No. 1, pp. 136–147, January–February 2008.  相似文献   
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提出了一种被遮挡单元的裁剪算法,以加速非规则数据场的体绘制过程。在基于一组平行切割平面的体绘制方法上,新算法通过对图像不透明度缓冲区中的值进行求平均操作,并将所计算的结果存储在一个与不透明度缓冲区间同样大小的平均不透明度缓冲区中,使得只需根据每一数据单元重心投影点在平均不透明度缓冲区中的值,就可得到此数据单元的可见性,从而有效裁剪掉被遮挡单元,降低需处理的数据量,加速体绘制过程。  相似文献   
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This paper compared the degradation efficiency of sludge organic matters and electric-production by two typical microbial fuel cells——dual-chamber microbial fuel cell(DMFC)and single chamber air cathode microbial fuel cell(SAMFC),and the variations of sludge protein,polysaccharide and ammonia nitrogen within the systems were also investigated.The results showed that the concentration of sludge soluble chemical oxygen demand,protein and carbohydrate of DMFC are higher than these of SAMFC during the systems operation,while DMFC can achieve a better ammonia nitrogen removal than SAMFC.Under the same operation condition,the stable voltage output of DMFC and SAMFC is 0.61 V and 0.37 V;the maximum power density of DMFC and SAMFC is 2.79 W/m3and 1.25 W/m3;TCOD removal efficiency of DMFC and SAMFC is 34.14%and 28.63%for 12 d,respectively.Meanwhile,DMFC has a higher coulomb efficiency than SAMFC,but both are less than5%.The results showed that DMFC present a better performance on sludge degradation and electric-production.  相似文献   
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The electro-oxidation of dimethyl ether (DME) on PtMe/Cs (Me = Ru, Sn, Mo, Cr, Ni, Co, and W) and Pt/C electro-catalysts were investigated in an aqueous half-cell, and compared to the methanol oxidation. The addition of a second metal enhanced the tolerance of Pt to the poisonous species during the DME oxidation reaction (DOR). The PtRu/C electro-catalyst showed the best electro-catalytic activity and the highest tolerance to the poisonous species in the low over-potential range (<0.55 V, 50 °C) among the binary electro-catalysts and the Pt/C, but at the higher potential (>ca. 0.55 V, 50 °C), the Pt/C behaved better than PtRu/C. The apparent activation energy for the DOR decreased in the order: PtRu/C (57 kJ mol−1) > Pt3Sn/C (48 kJ mol−1) ≈ Pt/C (46 kJ mol−1). On the other hand, the activation energy for the MOR showed a different turn, decreased in the following order: Pt/C (43 kJ mol−1) > Pt3Sn/C (35 kJ mol−1) ≈ PtRu/C (34 kJ mol−1). The temperature dependence of the DOR was greater than that of the oxidation of methanol (MOR) on the PtRu/C.  相似文献   
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