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Climatic changes in the western Pacific marginal seas are influenced by global forcing and regional processes, including monsoons, and ocean circulation. To better understand the process of hydrographic and temperature changes, we applied the UK′37 as our index of Sea Surface Temperature (SST) and TEX86 as the index of Subsurface Water Temperature (SWT) for the last 8400 years using the sediment core MZ01 from the continental shelf of the East China Sea (ECS). To focus on centennial and millennial variabilities, the original SST and SWT are filtered with the Ensemble Empirical Mode Decomposition (EEMD) of the Hilbert-Huang Transform (HHT), with the confidence defined by a new method, the Continuity Superposition Error Calculation Method (CSECM). The SST and SWT both have a quasi-period of 1000–2000 years, exhibiting some teleconnection with the north Atlantic climatic changes. The SWT decreased during approximately 6–4 ka and then increased by ∼4°C to the late Holocene, almost anti-phase with the SST. The stronger Asian winter monsoon and China Coastal Current (CCC), are very likely responsible for the decreased SST in the late Holocene. In contrast, the increased SWT may imply that the stronger CCC has brought more Changjiang Diluted Water (CDW) southward and formed a thicker barrier layer in the ECS, which dampened bottom water heat loss that was transported from the Taiwan Warm Current (TWC), and Western Kuroshio Branch Current (WKBC). This process is tested by the hosing experiment that supports stronger stratification when the north Atlantic cooled. The combined results by UK′37 and TEX86 provide a new insight into the interaction mechanism among the winter monsoon, precipitation and the Kuroshio Current, and also raises caution to take more regional factors into account in the application of TEX86.

We fabricated and characterized ultraviolet (UV) light-emitting diodes (LEDs) composed of n-ZnO/SiO2-ZnO nanocomposite/p-GaN heterostructures. Significant UV electroluminescence at 387 nm from the n-ZnO layer in this heterostructure LED was observed at a forward-bias current of as low as 1.8 mA. This is ascribed to the high quality of the n-ZnO layer and the effective function of the SiO2-ZnO nanocomposite layer. The SiO2-ZnO nanocomposite layer accomplishes the role of current blocking by forming the larger energy barrier for electron injection from n-ZnO into p-GaN and also contributes to, due to its low refractive index, higher light extraction efficiency from the n-ZnO layer. [ABSTRACT FROM AUTHOR]