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This study reports magnetic graphene oxide composite microspheres (MGO) were firstly synthesized via one step miniemulsion polymerization. α-FeOOH rods were then loaded onto MGO via a facile hydrothermal method to prepare α-FeOOH@MGO, which was served as the photocatalyst for the Fenton reaction. Subsequently, the properties of the resulting α-FeOOH@MGO were characterized by FT-IR, XRD, SEM, VSM and UV-vis DRS analysis methods. The influence of various parameters was investigated, such as dye type, dye concentration, H2O2 dosage, catalysts dosage and pH of MO solution during heterogeneous photo-Fenton processes. Under visible light irradiation, the degradation rate of MO, MB and CR could reach 99.96%, 98.47% and 99.97% in 40 min, respectively. Six cycle experiments confirmed that the α-FeOOH@MGO possessed a satisfied stability and recycling ability. In addition, the photocatalytic reaction mechanism was also revealed by the Mott-Schottky plot, band structure and trapping experiments of active species.

The interfacial reactions and growth kinetics of Sn–Ag–Cu were investigated during solid-state aging. The effects of chemical composition on the interface structure and the growth of interface under high temperature and high humidity were experimentally and numerically studied. Three solders Sn–0.4Ag–0.7Cu, Sn–0.7Ag–0.7Cu, and Sn–1.0Ag–0.7Cu were used to conduct several experiments. In order to determine the long-term reliability of the solder joints, thermally accelerated aging tests were performed for 0, 10, 30, 50, 100, and 350 h at 85 °C and 85% relative humidity. The surface morphology, thickness, and distribution of compounds were observed by scanning electron microscopy. The results showed that with increasing Ag content, the growth of Cu6Sn5 layer suppressed. The growth kinetics of intermetallic compound (IMC, Cu6Sn5 + Cu3Sn) remained a diffusion-controlled process during the isothermal aging, and Cu6Sn5 gradually transformed into a Cu3Sn IMC. The scallop-like shape disappeared at later aging stages, suggesting a change in the growth mechanism to the steady growth in the perpendicular direction to the interface. In addition, the results revealed that Ag effectively slowed the growth kinetics of Cu6Sn5. The apparent activation energy Q for Cu6Sn5 + Cu3Sn IMC of interfaces at Sn–0.4Ag–0.7Cu/Cu, Sn–0.7Ag–0.7Cu/Cu, and Sn–1.0Ag–0.7Cu/Cu was calculated to be 69.11, 88.90, and 56.61 kJ/mol, respectively.

Herein, we prove that alloying of reactive nanoparticles can improve nanoparticles/β-Sn interfacial bonding and influence the solder alloy's melting point. Furthermore, the alloying effect can enhance the creep resistance of solder alloy. 0-0.5 wt% Ag nanoparticles (NPs) were added to Sn3.0Ag0.5Cu (SAC305) solder paste by mechanical stirring for the preparation of composite solder alloys, which were then extracted from the composite solder pastes. The joints were observed by scanning electron microscope and transmission electron microscope. The elementary composition of the prepared alloys was analyzed by electron dispersive spectrometer. The melting properties of alloys were tested by differential scanning calorimeter. The influences of Ag NPs as reactive nanophase on solder microstructure and melting properties were studied. The results indicated the existence of transition layer at the interface between Ag NPs and β-Sn. Additionally, the interfacial bonding improved after Ag NPs converted to Ag3Sn NPs. Due to Ag NPs alloying and solder alloy microstructure refinement being affected, melting points of alloys increased with 0-0.2 wt% addition of Ag NPs and decreased with 0.2–0.5 wt% addition.

The purpose of this study is to investigate the influence of alloy composition on the evolvement rule of microstructure for ZL201 cast aluminium alloy. The ZL201 casting samples with different components were prepared by gravity diecasting process, the phase composition was characterized and calculated by x-ray diffraction (XRD) and thermo-calc (TC) software respectively, the evolvement rule of microstructures was observed by metallographic microscope (OM) and scanning electron microscope (SEM), and simulated by ProCAST software. The results show that the Al2Cu (θ) formed by Cu and Al matrix, which increased the free energy and reduced the precipitation temperature for the alloy system. For the microstructure of ZL201, the nucleation direction of Al-Cu was along the positive direction of z-axis, the morphology was a regular ribbed morphology; Al-Mn and Al-Ti were along the negative directions of x- and y-axis and morphologies were columnar. Besides, the nucleation mode of casting center was dominated by the growth pattern of Al-Cu, and that of casting surface was dominated by Al-Ti and Al-Mn.

First principle calculations based on DFT have been applied to study various properties of rutile (110) surface. We used a nine_layer slab model with stoichiometric formula of TiO2 and the vacuum length of the cell fixed at 15nm. The interactions between ionic core and valence electrons were represented by pesudopotentials. After analyzing the results, we found that an admixture bonding states existed in titanium dioxide: a stronger ionic bond accompanied by a weaker covalent bond between Ti and O. STM(Scanning tunneling microscope)image of Rutile (110) surface has been successfully simulated by DFT calculations, which was in accord with the Tersoff-Hamann's theory. A positive basis voltage of 2V was added to simulate STM experimentd conditions in imaging process. The distance between tip and surface were also changed step by step. By analyzing the electron density map and DOS plot, it is clear that electron factors dominated the STM image of rutile (110) surface and the jut in the image corresponded to 5_coordinated Ti atom rather than the bridge oxygen on the top.