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Due to the acceleration of industrialization, air pollution has become increasingly severe. As a result, the management of NOx and VOCs has become a major concern. NH3-SCR and catalytic oxidation of VOCs are recognized as the most effective solutions. However, the selectivity, stability, and operating temperature range of the catalytic process are the primary constraints of the reaction. Therefore, there is growing interest in improving the efficiency, resistance, stability, and selectivity of catalysts. The core-shell structure is an emerging catalyst that offers significant advantages over loaded catalysts. It helps to avoid sintering, improves the catalyst's resistance to chlorine and sulfur poisoning, enhances its efficiency, and enables the complementarity of different active sites. This paper reviews the current research status of core-shell catalysts in the field of atmospheric catalysis. The focus is on the synthesis method, structural characteristics, catalytic process, and anti-poisoning mechanism of core-shell catalysts. Finally, this review presents the challenges in designing core-shell catalysts, the unknown synergistic mechanisms in the reaction process, and the economic considerations. The aim is to improve future development of NH3-SCR and catalytic degradation of VOCs technology.

Digital Speckle Pattern Interferometry (DSPI) is one of modern optical measurement techniques. It has the advantage of non-contacting, whole field, high measurement accuracy and without special process of the surface to be measured. With the development of computer science and electronics, DSPI is used more and more widely. This paper systematically presents the principle of speckles and measurements by DSPI. Optical measurement system based on DSPI was built for demonstrate. In order to quantitative determination of the distribution of phase change, several imaging process and pattern evaluation methods are discussed and compared. Phase shifting techniques and phase pattern filter methods also were described in detail. In this paper, some experiments results were given, which clearly demonstrate that that the methods are effective for processing pattern.