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991.
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Hoo Kun Lee Myeong Soo Jeong Joo Wan Park Hyun Soo Park Jong Hyun Cho 《Korean Journal of Chemical Engineering》1990,7(1):13-17
An absorption efficiency of packed column removing nitrogen oxides with water and NaOH solution under atmospheric pressure
was studied. The efficiency and the acidity produced by absorption of NO, were measured in a packed column. The model developed
that was based on the mass-transfer information for packed column and absorption mechanism accompanying the chemical reaction
was compared with experimental results. Predictions using the model presented by the previous paper (part 1) was shown well
to agree with from the experimental results (part II). The efficiency of NOx, absorption is largely dependent on the height of packing material and the partial pressure of NOx in the feed gas. The efficiency of NOx absorption decreases with the increase of the acidity produced by recycling of water as a scrubber liquid. For the recycle
mode with an aqueous NaOH solution as a scrubber liquid, NOx absorption efficiency is shown to be constant until all of the COH- in the scrubber liquid are converted into CH+. 相似文献
994.
用固态配料和硝酸盐共沉淀配料制备了各组份为(Bi_(1.85)Pb_(0.40))Sr_(1.95)Ca_(2.05)Cu_(8.10)的超导材料,研究了两种不同制备工艺对Bi系超导相形成过程、超导电磁性能和显微结构的影响.实验发现,由共沉淀制备的样品T_(c(zero))稳定性好,T_(c(zero))均在107.5K以上.SEM观察表明:共沉淀法制备的样品中超导相颗粒比固态配料制备的要细小、均匀,颗粒间连结紧密,与T_(c(zero))结果相符.但XRD相分析结果显示:固态配料样品中高温相含量高于共沉淀配料,共沉淀配料制备作品中高、低温相同时存在,但其交流磁化率—温度曲线上仅在120K附近出现相应于高温相的抗磁信号.研究认为,这是由于共沉淀配料烧成时,高温相容易在部分液相参与下,在低温相表面通过反应成核生长,导致在形成的高温相内部包裹有残余低温相的“内芯”.依此包裹模型可自洽地解释X射线相分析与电、磁性能测定结果间的矛盾,讨论了Bi系高温相的形成机理,为选择合理的制备工艺提供了依据. 相似文献
995.
基于热管技术的锂离子动力电池热管理系统研究进展 总被引:1,自引:0,他引:1
近年来,锂离子动力型电动汽车炙手可热,但它的广泛应用还受限于电池性能、寿命及使用安全等问题。锂离子电池在25~40℃内可高效安全运行,这就需要配备高效的热管理系统以保障整车安全。本文针对锂离子电池,主要综述了包括风冷、液冷、相变材料冷却和热管冷却等热管理技术的研究进展。通过分析研究发现,目前应用的热管理技术不仅在极端条件下冷却能力不足,而且存在结构复杂、体积及质量过大等缺点,既增加了电池的额外能耗,也与汽车轻量化的发展方向相悖。针对于此,本文提出开发超薄型热管的冷却技术,并认为热管和相变材料耦合的热管理技术将有效解决锂离子电池的散热与蓄热问题。 相似文献
996.
Chien Hwa Chong Chung Lim Law Michael Cloke Luqman Chuah Abdullah Wan Ramli Wan Daud 《Drying Technology》2013,31(10):1286-1293
Sun drying of chempedak (Artocarpus integer) was carried out on different sample sizes to investigate the effects on product quality. Fick's second law model was used to determine the effective diffusivities of sun–dried chempedak slabs based on the drying rate versus moisture content plots. In addition, texture degradation and total color changes were investigated. The texture and color changes of dried chempedak were relatively significant (p < 0.05) compared to fresh chempedak. There was an increase in dried fruit hardness and chewiness but a decrease in springiness and cohesiveness during drying. 相似文献
997.
Zhenyong Miao Jingpeng Chen Yongjiang Wan Keji Wan Mingqiang Gao 《Drying Technology》2013,31(13):1731-1742
AbstractThis paper investigated the thermal fragmentation of three lignite samples with temperature of 100?°C–200?°C and drying time of 0–90?min using the fixed bed reactor. The effects of a variety of factors such as temperature and drying time on fragmentation ratio were studied. The results showed that fragmentation ratio was positively related to temperature and drying time, and the degree of fragmentation was different for different lignite samples. Additionally, it was demonstrated that the point load strength remarkably decreased with the increase of temperature and drying time. The fragmentation ratio as a function of point load strength represented that lignite with higher strength had a lower fragmentation ratio, and the possibility of secondary fragmentation of dried lignite decreased with the increase of point load strength. Fragmentation ratio decreased with the increase of lignite density. The mineral matters of lignite significantly had influence on fragmentation. The mass inhomogeneity degree was given to depict the mineral element compositions. A fragmentation prediction equation was established based on mass inhomogeneity degree, which was associated with moisture content and ash content. 相似文献
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