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UV-C irradiation can maintain fruit quality by inducing fruit disease resistance and reducing decay during storage. Grape (Vitis Vinifera L.) was exposed to 2.4 kJ m−2 UV-C irradiation then inoculated with Aspergillus carbonarius to investigate the changes in nutritional quality, defense related substances and enzyme activities. Postharvest UV-C irradiation can increased the levels of defense-related substances and enzyme activities, such as phenols, flavanols, lignin, proline, glutathione, phenylalanine ammonia-lyase (PAL), polyphenol oxidase (PPO), and β-1,3-glucanase (GLU). In addition, Resveratrol plays an important role in grape resistance to A. carbonarius infection through further verification by gene expression levels, the transcription factors VvWRKY24 and VvMYB14 are highly correlated with the regulation of VvSTS gene expression. This study revealed the molecular mechanism of postharvest grape fruit response to UV-C irradiation and the defense mechanism against black rot, and provided a theoretical basis for postharvest grape storage and preservation technology. • UV-C irradiation maintained storage quality of grapes. • UV-C irradiation induced resistance against A. carbonariu. • UV-C irradiation elevated activity of defense-related enzyme and phenolics content. • UV-C irradiation accelerated the biosynthesis of phenolic substances. • Resveratrol was a important defense substance during resistance induction. [ABSTRACT FROM AUTHOR]

Abstract With the aim of application as either a conductive filler or a sinter-bonding material with enhanced antioxidation properties, Ag-coated Cu (Cu@Ag) particles with thick Ag shells were fabricated and heated at 220 °C for 10 min in air to observe the dewetting behavior of the thick Ag shell. The fabricated Cu@Ag particles were spherical with the average size of 2 μm, and the Ag shell was 250–400 nm in thickness, comprising a mixed Ag-Cu layer and a dense Ag layer. As the heat-treatment time increased, the Cu@Ag particles were aggregated by forming numerous Ag nodules covering the surface of the particle. Dewetting in the thick Ag shell occurred from 4 min and only in the outer layer of the Ag shell even after 10 min of heat-treatment. In addition, the thickness of the dewetting layer and the mixed Ag-Cu layer were increased because the outward diffusion of Cu and Ag were increased proportionally with the time. However, because the dense Ag layer remained even after the dewetting of the Ag shell and the formation of the mixed Ag-Cu layer, the Cu@Ag particles were not oxidized after heating at 220 °C for 10 min in air. Highlights • Ag-coated Cu particles with thick Ag shells were fabricated and heated at 220 °C in air. • Thickness of dewetting layer, dense Ag layer, and mixed Ag-Cu layer changed during heating. • Ag-coated Cu particles became highly sintered by forming a dewetting layer in the outer shell. • Diffusion of Cu and Ag was accelerated by the instability of the Cu/Ag interface. • The dense Ag remained even after the heating, which improved anti-oxidation properties. [ABSTRACT FROM AUTHOR]

Abstract: To improve the ultrasonic bondability and antioxidation property of pure Cu pad, multi-layer structures of Ti/Cu/TaN/Ag are deposited on Si substrate with magnetron sputtering technology. The as-deposited multi-layers had uniform thicknesses and smooth surface with the roughness of 2.098nm. X-Ray diffraction analysis indicated that both Ag and Cu layers had deposited with (111) preferred orientation, and the grain size of Ag layer was 29.5nm. The phase composition of TaN layer was Ta2N. For comparison of antioxidation properties, traditional pad structure Ti/Cu/Ag was also fabricated with the same process. Obvious Cu oxidation occurred on the surface of the Ti/Cu/Ag structure after heating at 150°C for 30min. However, no Cu element was detected on the surface of Ti/Cu/TaN/Ag structure even after heating at 300°C, which indicated that the Ta2N layer in Ti/Cu/TaN/Ag structure can prevent the underneath Cu pad from oxidation. 100% Au bondability was achieved on Ti/Cu/TaN/Ag structure under both room temperature and 150°C. The shear fractures mainly occurred in Au bonds, indicating the multi-layers fabricated by magnetron sputtering technology had strong bond interface with Cu pad. [Copyright &y& Elsevier]