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61.
This study proposed a new method, namely a tube-by-tube reduction method to analyze the performance of fin-and-tube heat exchangers having plain fin configuration under dehumidifying conditions. The mass transfer coefficients which seldom reported in the open literature, are also presented. For fully wet conditions, it is found that the reduced results for both sensible heat transfer performance and the mass transfer performance by the present method are insensitive to change of inlet humidity. Unlike those tested in fully dry condition, the sensible heat transfer performance under dehumidification is comparatively independent of fin pitch. The ratio of the heat transfer characteristic to mass transfer characteristic (hc,o/hd,o Cp,a) is in the range of 0.6~1.0, and the ratio is insensitive to change of fin spacing at low Reynolds number. However, a slight drop of the ratio of (hc,o/hd,o Cp,a) is seen with the decrease of fin spacing when the Reynolds number is sufficient high. This is associated with the more pronounced influence due to condensate removal by the vapor shear. Correlations are proposed to describe the heat and mass performance for the present plate fin configurations. These correlations can describe 89% of the Chilton Colburn j-factor of the heat transfer (jh) within 15% and can correlate 81% of the Chilton Colburn j-factor of the mass transfer (jm) within 20%. 相似文献
62.
The synthesis and properties of the ion exchange polymer 3‐n‐propyl(3‐methylpyridinium)silsesquioxane chloride (SiPy+Cl?) are described. Based on the Langmuir model, the equilibrium constant at the solid‐solution interface for the reaction, SiPy+Cl?+NO ?SiPy+NO , was calculated for nitrite adsorption. The value found, β=8.7×103 L mol?1, indicates good affinity of the anion for the solid phase. A carbon paste electrode of the material was tested for NO oxidation and a linear response, in the concentration range between 6.3 and 143.6 μmol L?1, was obtained by amperometry. The analytical applicability of the proposed system was ascertained by the satisfactory results attained in its application to monitoring of nitrite in natural waters. 相似文献
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分析了影响风机盘管换热器传热性能的主要因素并提出相应的解决措施.采用理论分析与计算的方法,从提高传热效率出发对热交换器进行了改进.对于企业降低生产成本、提升产品性能和提高市场竞争力具有重要意义. 相似文献
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Muriel De Bock Marie-Alice Meuwis Tran Quang Minh Jean-Paul Chapelle Michel Malaise Marianne Fillet 《Talanta》2010,82(1):245-594
In most diseases, the clinical need for serum/plasma markers has never been so crucial, not only for diagnosis, but also for the selection of the most efficient therapies, as well as exclusion of ineffective or toxic treatment. Due to the high sample complexity, prefractionation is essential for exploring the deep proteome and finding specific markers.In this study, three different sample preparation methods (i.e., highly abundant protein precipitation, restricted access materials (RAM) combined with IMAC chromatography and peptide ligand affinity beads) were investigated in order to select the best fractionation step for further differential proteomic experiments focusing on the LMW proteome (MW inferior to 40,000 Da). Indeed, the aim was not to cover the entire plasma/serum proteome, but to enrich potentially interesting tissue leakage proteins. These three methods were evaluated on their reproducibility, on the SELDI-TOF-MS peptide/protein peaks generated after fractionation and on the information supplied.The studied methods appeared to give complementary information and presented good reproducibility (below 20%). Peptide ligand affinity beads were found to provide efficient depletion of HMW proteins and peak enrichment in protein/peptide profiles. 相似文献
68.
在简化流程的基础上,对氨合成过程的循环机进行了模拟计算,考察了功与压力之间的关系和功与温度之间的关系,并获得了它们之间的关系曲线;对换热器进行了模拟计算,并得到了相应的结果. 相似文献
69.
1引言制冷设备中换热器是重要的部件,在进行换热器设计或对实际系统中换热性能进行计算时,采用的翅片效率的准确与否将会关系到整个系统的工作状况。对于换热器表面处于干或湿工况时,文献中的翅片效率公式形式较统一,但对结霜情况下的研究相对没有一致的结论[1]。Sanders[1]、Barrow[2]和Kondepudi[3]都曾提及霜工况下换热器翅片效率公式,此外还有包含析湿系数的翅片效率形式。由于所采用的结霜翅片效率表达式不同,最终得到的翅片效率及翅片温度分布也难免存在差别。因而,从众多公式中选择相对准… 相似文献
70.
板棒式换热器传热性能分析(Ⅰ)——圆柱肋棒的传热效率 总被引:2,自引:2,他引:0
对板棒式换热器中圆柱肋棒的传热效率做了分析,研究了在维持一定传热效率的条件下,肋棒的直径与棒长及传热操作条件间的相互关系。 相似文献