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Core-shell composite beads comprising a Pd-loaded Al2O3 core and a shell of inter-grown silicalite-1 (siliceous ZSM-5) crystals were synthesised. The incompatibility between the Pd/Al2O3 core and the zeolite shell was circumvented by a layer-by-layer self-assembly of polyelectrolyte to adsorb nanosized silicalite-1 seeds onto the core surface, followed by a secondary solvo-thermal treatment to form the continuous and well-intergrown silicalite-1 shell. The thickness of the outer zeolite shell could be tuned by monitoring the secondary growth time. When employed as catalyst for the hydrogenation reaction of alkenes to explore its full potential use, the Pd/Al2O3@silicalite-1 core-shell catalyst exhibited excellent size-selectivity, poison-resistance and leaching-proof properties. Such a catalyst@zeolite core-shell structure is expected to find promising applications in heterogeneous catalysis and adsorption. [ABSTRACT FROM AUTHOR]

In this study, the relationship between the subsystems of Asian summer monsoon is analyzed using U.S. National Centers for Environmental Protection/National Center for Atmospheric Research reanalysis and Climate Prediction Center Merged Analysis of Precipitation monthly mean precipitation data. The results showed that there is significant correlation between the subsystems of Asian summer monsoon. The changes of intensity over the same period show that weak large-scale Asian monsoon, Southeast Asia monsoon and South Asian monsoon are associated with strong East Asian monsoon and decreasing rainfall in related areas. And when the large-scale Asian monsoon is strong, Southeast Asia and South Asia monsoons will be strong and precipitation will increase. While the Southeast Asia monsoon is strong, the South Asia monsoon is weak and the rainfall of South Asia is decreasing, and vice versa. The various subsystems are significantly correlated for all periods of intensity changes. [ABSTRACT FROM AUTHOR]