[en] Peony seed oils (PSOs) were prepared using supercritical CO2 (SC) and compared with soxhlet extraction (SE) and mechanical screw press extraction (SPE) methods. The fatty acid compositions of the oils were determined, and the physicochemical properties of the oils, including free radical-scavenging activity, α-amylase and α-glucosidase inhibition, thermal and rheological properties were evaluated. The unsaturated fatty acids in the SE oils were higher than SC and SPE oils due to the higher percentage of olefinic, allylic methylene and allylic methine protons in the SE oils. The SPE oils also displayed the highest DPPH and ABTS+ radical scavenging activity at the tested concentrations. However, the SE oils showed stronger inhibitory effects on α-amylase and α-glucosidase enzymes under in vitro conditions when compared with the other oil samples. The three oils had similar melting and crystalline point due to similar contents of fatty acids (FAs). The SC oils had a lower Ea than the others.

[en] The microstructures of the hypo-peritectic Al-30 wt%Ni alloy solidified at different pressures are investigated. The results show that the microstructure is composed of eutectic, Al₃Ni, and Al₃Ni₂ phases when the alloy is solidified at ambient pressure. Bulk single phase Al₃Ni alloy area (2/3) and hyper-eutectic microstructure region (1/3) co-exist after solidified at 4 GPa with a superheat degree of 800 °C. However, the eutectic and Al₃Ni phases are homogeneously distributed when the alloy is solidified at the same pressure with no superheating. It provides a new method for preparing the bulk single-phase intermetallic compound. In addition, the Debye temperatures of the single-phase Al₃Ni alloy fabricated at different pressures are explored using the low temperature heat capacity curve. The results reveal that the Debye temperatures of the single phase Al₃Ni fabricated at ambient pressure and 4 GPa are 468.95 K and 516.7 K, respectively. Finally, the lattice parameters of Al₃Ni synthesized at 4 GPa are examined using transmission electron microscopy (TEM), which shows that the lattice parameters are a = 6.6814 Å, b = 7.1910 Å and c = 4.8351 Å.

[en] The microstructure and micromechanical properties of carbides in a near γ-TiAl base alloy with carbon addition prepared by arc-melting method were investigated. It was observed that there were two types of carbides in the alloy, single-phase TiC and dual-phase carbide. The dual-phase nature of the carbides was identified by transmission electron microscope (TEM) to consist of TiC phase and Ti₃AlC phase. In dual-phase carbide, TiC phase acts as the core and nucleation substrate, and the Ti₃AlC phase that grows around the core TiC phase acts as the coating layer. The micromechanical properties of dual-phase carbide and the surrounding matrix were examined by nanoindentation tests showing that both microhardness and elastic modulus decrease from the core of dual-phase carbide to the Ti₃AlC coating layer and then to the surrounding matrix gradually. The forming mechanism of dual-phase carbide and the role of Ti₃AlC coating layer on the mechanical properties were discussed.

[en] Highlights: • The composite with high Zr and Mo and low TiC contents shows high UTS below 650 °C. • High UTS is obtained in composite with high TiC and low Mo contents above 700 °C. • Matrix strengthening plays a dominant role in the enhancement of UTS below 650 °C. • Matrix strengthening and TiC load-bearing strengthening are all vital above 700 °C. • The effective routes for improving UTS in different temperature ranges are different. In this paper, five types of TiC particle reinforced titanium matrix composites (TiC-PTMCs) were fabricated by casting route in order to investigate the influence of Zr, Mo and TiC on microstructures and tensile strengths of TiC-PTMCs. The increase of Zr content promoted the precipitation of eutectic TiC and refined primary TiC, while increasing Mo content led to the refinement of α lath. The composites with high Zr and Mo contents and low TiC content showed superiority in ultimate tensile strength (UTS) below 650 °C, whereas above 700 °C, high UTS was obtained in the composites with high TiC content and low Mo content. Below 650 °C, solid solution strengthening and fine grain strengthening of matrix make the largest contribution to the improvement of UTS. However, above 700 °C, solid-solution strengthening of Zr and the load bearing effect of TiC play a dominant role in the enhancement of UTS. Accordingly, effective routes for improving UTSs of TiC-PTMCs in different temperature ranges are different.

[en] The precipitation in Al–Mg solid solution containing 21.6 at.% Mg prepared by solidification under 2 GPa was investigated. The results show that the γ-Al₁₂Mg₁₇ phase is formed and the β′ phase cannot be observed in the solid solution during ageing process. The precipitation of γ and β phases takes place in a non-uniform manner during heating process, i.e. the γ and β phases are first formed in the interdendritic region, which is caused by the inhomogeneous distribution of Mg atoms in the solid solution solidified under high pressure. Peak splitting of X-ray diffraction patterns of Al(Mg) solid solution appears, and then disappears when the samples are aged at 423 K for different times, due to the non-uniform precipitation in Al–Mg solid solution. The direct transformation from the γ to β phase is observed after ageing at 423 K for 24 h. It is considered that the β phase is formed through a peritectoid reaction of α + γ → β which needs the diffusion of Mg atoms across the interface of α/γ phases. - Highlights: • The γ phase is formed and the β′ phase is be observed in Al(Mg) solid solution. • Peak splitting of XRD pattern of Al(Mg) solid solution appears during aged at 150 °C. • The β phase is formed through a peritectoid reaction of α + γ → β

[en] Polystyrene/silica nanoparticles were prepared by radical polymerization of silica nanoparticles possessing vinyl groups and styrene with benzoyl peroxide. The resulting vinyl silica nanoparticles, polystyrene/silica nanoparticles were characterized by means of Fourier transformation infrared spectroscopy, scanning electron microscopy and UV-vis absorption spectroscopy. The results indicated that polystyrene had been successfully grafted onto vinyl silica nanoparticles via covalent bond. The morphological structure of polystyrene/silica nanoparticles film, investigated by scanning electron microscopy, showed a characteristic rough structure. Surface wetting properties of the polystyrene/silica nanoparticles film were evaluated by measuring water contact angle and the sliding angle using a contact angle goniometer, which were measured to be 159^o and 2^o, respectively. The excellent superhydrophobic property enlarges potential applications of the superhydrophobic surfaces.

[en] The rates of radial oxygen loss (ROL), root porosity, concentrations of arsenic (As), iron (Fe) and manganese (Mn) in shoot and root tissues and on root surfaces, As tolerances, and their relationships in different wetland plants were investigated based on a hydroponic experiment (control, 0.8, 1.6 mg As L^-1) and a soil pot trail (control, 60 mg As kg^-1). The results revealed that wetland plants showed great differences in root porosity (9-64%), rates of ROL (55-1750 mmo1 O₂ kg^-1 root d.w. d^-1), As uptake (e.g., 8.8-151 mg kg^-1 in shoots in 0.8 mg As L^-1 treatment), translocation factor (2.1-47% in 0.8 mg As L^-1) and tolerance (29-106% in 0.8 mg As L^-1). Wetland plants with higher rates of ROL and root porosity tended to form more Fe/Mn plaque, possess higher As tolerance, higher concentrations of As on root surfaces and a lower As translocation factor so decreasing As toxicity. - Research highlights: → There is significant correlation between the porosity of roots and rates of ROL. → The rates of ROL are significantly correlated with tolerance indices and concentrations of As, Fe, Mn on root surface. → The rates of ROL is negatively correlated with As translocation factor. - Wetland plants with high rates of ROL tended to form more Fe plaque on root surfaces and possess higher As tolerance.

[en] Styrene and 2,2,3,4,4,4-hexafluorobutyl methacrylate copolymers were synthesized by bulk polymerization, and the superhydrophobic copolymer films were prepared subsequently using phase separation technique. The copolymer was dissolved in tetrahydrofuran, and then added ethanol into the solution thereafter, to induce phase separation. The microstructures of the polymer films were controlled by the degree of phase separation, which was enhanced properly by the concentration of ethanol. The surface morphology of the films, observed by environmental scanning electron microscope, is similar to that of the lotus leaf. The contact angle and sliding angle were measured as 154.3 deg. and 5.8 deg., respectively. The excellent superhydrophobic property demonstrated that the phase separation technique is useful for preparing lotus-like fluoropolymer films.

[en] A facile process for the one-step preparation of a fluoropolymer superhydrophobic polymer-coated surface under an ambient atmosphere was reported in this study. The block copolymer of polystyrene-block-poly (2,2,3,4,4,4-hexafluorobutyl-methacrylate), synthesized by atom transfer radical polymerization, was dissolved in a selective solvent. With the evaporation of the solvent, the block copolymer self-assembled into core/shell micelles, forming a grain-structured superhydrophobic film. The contact angle and sliding angle of the film were measured as 152.3^o and 9.2^o, respectively, demonstrating excellent superhydrophobic property and stability. The superior performance should ascribe to the introducing fluorine into the copolymer and the grain-like rough morphology of the film.

[en] Highlights: •Al–42.2Mg alloy was solidified under pressures of 1, 2, and 3 GPa and the microstructure analyzed. •A thermodynamic calculation of the Al–Mg phase diagram at high pressures was performed. •The phase content changes from predominantly γ-Al₁₂Mg₁₇ at 1 GPa to FCC solid solution at 3 GPa. •The β-Al₃Mg₂ is predicted to remain stable at low temperatures but is not observed. •The alloy solidified at high pressure has remarkably enhanced ultimate tensile strength. -- Abstract: Phase formation, the microstructure and its evolution, and the mechanical properties of an Al–42.2 at.% Mg alloy solidified under high pressures were investigated. After solidification at pressures of 1 GPa and 2 GPa, the main phase is the γ phase, richer in Al than in equilibrium condition. When the pressure is further increased to 3 GPa, the main phase is the supersaturated Al(Mg) solid solution with Mg solubility up to 41.6 at.%. Unlike in similar alloys solidified at ambient pressure, the β phase does not appear. Calculated high-pressure phase diagrams of the Al–Mg system show that although the stability range of the β phase is diminished with pressure, it is still thermodynamically stable at room temperature. Hence, the disappearance of the β phase is interpreted as kinetic suppression, due to the slow diffusion rate at high pressures, which inhibits solid–solid reactions. The Al–42.2 at.% Mg alloy solidified under 3 GPa has remarkably enhanced ultimate tensile strength compared to the alloy solidified under normal atmospheric pressure