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51.
52.
固体氧化物燃料电池(SOFC)作为第三代燃料电池,以其能量转换效率高、燃料适用范围广、对环境友好、全固态等诸多优势而备受关注.双极板(又称连接体)作为固体氧化物燃料电池的重要组成部分之一,在SOFC电池堆中起到串并联单体电池并隔绝燃料气体与空气的作用,对电池性能及商用成本有很大影响.不同材料的双极板存在不同的性能问题,主要都集中在导电性能、抗氧化性能、化学稳定性及热膨胀系数是否匹配等方面.本文综述了传统陶瓷材料、合金材料、新型陶瓷材料、复合材料双极板的发展历程及最新研究进展,并着重介绍了组分优化设计及表面改性(涂覆活性氧化物涂层、稀土钙钛矿涂层及尖晶石涂层等)两种方式对于合金材料抑制镉元素向外扩散的能力、抗氧化性及导电性的改善.综合分析表明,通过组分优化设计和表面改性弥补合金作为双极板材料的性能缺陷,尝试制备新型陶瓷材料或复合材料等途径,有望获得高性能、低成本的双极板材料,从而实现SOFC的大规模商业化应用. 相似文献
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介绍了粉末涂料的喷涂工艺流程、喷涂设备及烘干系统,对多颜色串色问题提出了解决方案,制定了汽车车厢用粉末涂料的技术指标,并举例说明了验证粉末涂料与前处理电泳防腐配套性能的方法. 相似文献
55.
Shu Yan Fanyong Zhang Xue Feng Jian Kong Bo Wang Jinlong Yang 《International Journal of Applied Ceramic Technology》2021,18(3):817-829
A hierarchical porous cenosphere/geopolymer composite foam (FHCs/KGP) was fabricated by the simultaneous incorporation of O2 pore from hydrogen peroxide and cenosphere filler addition. Effects of both H2O2 content and high-temperature treatment on the microstructure, porosity and strength of porous FHCs/KGP foams were investigated systematically. The obtained FHCs/KGP foams showed typical amorphous structure and desirable porosity from 65 to 82%. The composites could crystallize in situ to FHCs/leucite foams above 1000℃. Compression strength of the FHCs/leucite foams showed a maximum value of 5 ± 0.3 MPa when treated at 1000°C. The improvement of mechanical properties for the composite foams was attributed to crack deflection, fractured microspheres and the good bond between the FHCs and matrix. This study could open opportunities to employ cellular foams as alternatives in structure and filtration applications. 相似文献
56.
研究了以碳酰胺为助浸剂的风化壳淋积型稀土矿浸取稀土工艺。通过柱浸方式模拟原地浸出过程,在单因素试验基础上,采用响应曲面法建立二次多项数学模型,以稀土浸取率为响应值,探究助浸剂碳酰胺浓度、浸取温度和浸取剂溶液pH对稀土浸取率的影响,分析各因素间的交互作用。结果表明,影响稀土浸取率从强到弱的因素依次是浸取剂溶液pH、碳酰胺浓度、浸取温度。在浸取剂乙酸铵浓度0.10 mol/L条件下,最佳工艺参数为碳酰胺浓度0.59 mol/L、浸取温度25.03 ℃、浸取剂pH=5.51,该条件下稀土浸取率响应值为97.50%。实际试验稀土浸取率为96.36%。两者误差较小,表明采用响应曲面模型得到的工艺参数是基本可靠的。 相似文献
57.
58.
Mercury transformation across particulate control devices in six power plants of China: The co-effect of chlorine and ash composition 总被引:2,自引:0,他引:2
This paper presents the results of field measurements on mercury speciation in six power plants of China by applying the Ontario hydro method. During the tests, flue gas was sampled simultaneously before and after particulate control devices (electrostatic precipitator and fabric filter baghouse) along with the pulverized coal, bottom ash and fly ash sampling. The amount of oxidized mercury in gas phase before and after ESP/FF suggests that mercury oxidation after combustion is a kinetically controlled process. The comparison of mercury speciation in different power plant indicates a clear relationship with coal type, especially the chlorine concentration and the basic ash compositions in coal. Both of the factors are analyzed quantitatively in this study. A new parameter C (ratio of chlorine in coal to base/acid ratio) has been introduced to evaluate the co-effect of the two factors above on mercury speciation. 相似文献
59.
Lingzhi Wang Yaofeng Shao Jinlong Zhang Masakazu Anpo 《Microporous and mesoporous materials》2007,100(1-3):241-249
The hydrothermal stability of MCM-48 was conveniently and effectively improved by increasing the crystallization temperature and directly adding NaF to the synthesis gel. The crystallization temperature varied from 373 K to 403 K. The influences of NaF addition, crystallization temperature and crystallization time on the formation process and hydrothermal stability of MCM-48 were systematically studied here to solve the problem of poor reproducibility. Results from XRD patterns indicated that the crystallization temperature and crystallization time were very critical factors for the improvement of the hydrothermal stability besides NaF addition. The formation process of MCM-48 was significantly accelerated and the pore structure ordering was also greatly improved by increasing the crystallization temperature and F−/Si ratio. A high hydrothermally stable MCM-48 mesoporous molecular sieve was obtained after being crystallized at 393 K for 36 h in the presence of NaF, which endured the hydrothermal treatment in boiling water at least for 4 days. However, only an amorphous product was obtained when the crystallization temperature was further increased to 403 K. Results from Si MAS NMR, N2 adsorption isotherms, TEM, Raman spectra and XRD patterns manifested that the improved stability of MCM-48 was attributed to the high silicates condensation degree and the excellent pore structure ordering. The possible reason for the successful formation of hydrothermally stable MCM-48 sample by controlling the crystallization temperature, time and F−/Si ratio was explained here. 相似文献
60.
结晶性高聚物作为相变材料的应用 总被引:3,自引:0,他引:3
本文研究了结晶性高聚物聚乙烯及其共混物作为相变材料对模拟发热体铜片热量的吸收作用,由于相变的吸热,铜片的温度在一定时间范围内保持在一个定值。选择不同的相变材料,可使这种温度平台出现在不同的温度范围,不共晶的共混物可有两个以上的温度平台,提高了降温效果。 相似文献