The Three Gorges are considered to be critical to understand the formation of Yangtze River. Recent research results suggest that the Yangtze Three Gorges was created during the Quaternary but the exact time is debatable. Fe–Ti oxide minerals are seldom used to study sediment provenance, expecially using scanning electron microscopy (SEM), and energy dispersive spectrometer (EDS). In this study, the provenance of Quaternary sediments in Yichang area, which is located to the east of the Yangtze Three Gorges, was investigated by using SEM and EDS to research Fe–Ti oxides. The Panzhihua vanadium titanomagnetite and Emeishan basalt outcrop are located to the west of the Three Gorges. Further, the materials from them are observed in the Quaternary sediments of Yichang area. Fe–Ti oxide minerals from the Huangling granite are observed in the Yunchi and Shanxiyao Formations, which were formed before 0.75 Ma B.P., whereas Fe–Ti oxide minerals from the Huangling granite, Panzhihua vanadium titanomagnetite, and Emeishan basalt are observed in the riverbed and fifth‐terrace sediments of the Yangtze River, which were formed after 0.73 Ma B.P.. Thus, we can infer that the Three Gorges formed after the deposition of the Shanxi Formation and before the fifth‐terrace; i.e., 0.75–0.73 Ma B.P..

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For continuous production of electromagnetic shielding fabrics, in short time, 3 min., copper, silver, tin and nickel were used to fabricate the coating by magnetron sputtering. By analysis and comparison of depositing rate, dB value and SEM images, the multi-layer displays an inhibition of the electromagnetic shielding effectiveness (ESE), which may resulted from the metal contact potential. It is found that the ESE of the multi-layer rely on the continuity of the bottom layer structure. The bridge-linking of the top layer particles seems lead to the slight increase in particle continuity in the lower layer and hence the ESE of the multi-layer increases somewhat compared to the single silver layer obtained for less time. After the screening experiment, silver has been chosen to fabricate single coating on the PET fabric. The fabric prepared by optimizing parameters has excellent ESE and potential application.

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