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The nanoparticle-polymer composite is a widely used electronic packaging material. To satisfy the miscibility of nanoparticles with polymer, the surface of nanoparticles needs to be modified. The particle surface modification has been widely studied. However, the interaction between the silane coupling agent (SCA) and the nanoparticle surface is not clear yet. This article aims to investigate the surface modification impact on the nano-SiO 2 particle surface and to clarify the interaction between chemical reagent and the particle surface. In this investigation nano-SiO 2 was characterized by thermal gravity analysis (TGA), Fourier transform infrared spectroscopy (FT - IR), and nano- IR. The FT - IR results showed that the specific peak of SCA appears in the synthesized nano-silica. The TGA experiments were carried out to test the weight loss of SCA modified nano-SiO 2 as well as the grafting efficiency of the surface modification. The FT-IR and TGA results confirmed the SCA chemical grafting onto the nanoparticle surfaces. The nano-IR test provided detailed information for nano-silica surface. It could not only show the topographical AFM images but also the corresponding nanoscale IR adsorption spectra of the nano-silica surface. The topographic image distinguished the nanoparticle from the substrate. The discrete domains spectra shows the existence of SCA on the silica surface, which indicated that the SCA was grafted onto the silica surface with chemical bonding.

Ferromagnetic Fe33Co30Ni16Al7Mn9W5 high-entropy films of BCC-structure solid solution were synthesized by RF magnetron sputtering with mosaic targets at different substrate temperature of 20 °C, 200 °C, 400 °C and 600 °C. Hardness and resistivity were measured by the methods of nanoindentation and four-point probe, respectively. Magnetization hysteresis loops were obtained by a vibrating sample magnetometer. Oriented grain growth of (2 1 1) was observed in the films deposited at 400 °C and 600 °C. Substrate-temperature elevation led to the variation of film-growth mode. The films showed high hardness and electrical resistivity. Electron-surface scatter generated by mesoscopic-scale roughness played a decisive role in the monotone increase of the films’ resistivity as substrate temperature rose. The optimal balance of magnetic and electrical properties was achieved at substrate temperature of 400 °C.

Shuffled frog leaping algorithm (SFLA) is meta-heuristic for solving complex optimization problems. It is one of promising optimistic methods which are based on swarm intelligence. SFLA combines the advantages of memetic algorithm and particle swarm optimization and has been widely used in engineering fields. In order to overcome the shortcomings of local search in the classic SFLA, a novel update method with convergence property is presented in this paper. On the basis of the proposed approach, the modified SFLA is presented afterwards. Experimental results show that the efficiency and convergence of the modified SFLA can be enhanced significantly.