Anti-condensation is important in various fields, e.g., transportation, power transmission, internal drying of precision instruments. Vapor sink is an important manner to suppress the happening of water vapor condensation, and shows potentials in some special scenarios. However, the mechanism of anti-condensation by vapor sink is not well understood up until now. In this article, the effect of substrate temperature on the dry zone generated by vapor sink were systematically studied with experiments and theoretical analysis. First, the effect of hygroscopic solutions on the local humidity were measured. The results indicated that the local humidity level near the hygroscopic solutions was effectively suppressed, reducing the water vapor condensation. Second, the variation of the dry zone with the cooling substrate temperature was systematically studied. The results indicated that the dry zone exhibits a hyperbolic relationship with the substrate temperature. The dry zone changing under different humidity conditions and cooling time were also studied. The dry zone remained approximately unchanged over time in a short period. Finally, a simple yet effective model between the dry zone and substrate temperature was deduced. The theoretical results are in good agreement with the experimental data. Our study may deeper the understanding of condensation suppression via vapor sink and offer guidance to the design of anti-condensation or anti-icing surfaces.
Ting Ge,Qiuyun Wang,Anmin Chen,Xun Gao,Mingxing Jin
This study combined the electro-deposition (ED) method with laser-induced breakdown spectroscopy (LIBS) to detect trace metal Pb and Cr elements in water. First, the trace metal Pb and Cr elements in water were enriched to the surface of the Al metal substrate by the ED method. The effect of the Al substrate temperature (ST) on the emission intensity of Pb and Cr atoms was investigated. The emission of Pb and Cr atoms increased with increasing the Al ST. Second, the effect of Al ST on the quantitative analysis of Pb and Cr elements was studied. Moreover, the limit of detection (LOD) was calculated by the Long & Winefordner formula. Interestingly, as the Al ST increased from 25 °C to 200 °C, the LODs of Pb and Cr elements decreased from 17 and 12 ng mL−1 to 12 and 5 ng mL−1, respectively. Finally, the effect of Al ST on the detection accuracy of Pb and Cr elements in water was discussed. The discussion indicated that the accuracy of the quantitative analysis of Pb and Cr elements improved substantially by increasing the Al ST. Therefore, the study suggests that increasing the Al ST can enhance the detection ability and accuracy of trace metal elements in an aqueous solution by LIBS.
危险品化学品经营许可证（带存储）