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Black wheat bran is by-products of the black wheat processing， which is rich in many physiological active substances， including anthocyanins， phenolic acids and dietary fiber. In this study， the antioxidant activity of black wheat bran was extracted with different solvents and its antioxidant capacity was evaluated.The results showed that the dry matter yield of 75% ethanol extract was the highest， which was 10.72%. The content of total phenol extracted by 50% ethanol extract was the highest， which was 2.9 mg/ 100 mL. The scavenging power of DPPH was the strongest in 50% ethanol extract， and the antioxidant extraction capacity of DPPH was the strongest in 75% ethanol extract. 75% acetone extract had the strongest scavenging effect on ABTS， and 75% methanol extract had the strongest antioxidant extraction effect on ABTS. Therefore， the antioxidant capacities of different solvent extracts are different， and the comprehensive comparison shows that 50% ethanol is more suitable for the extraction of antioxidant active components from black wheat bran.

As one of the core hot components of aeroengines, the safe service of turbine blades is crucial to the operation of aeroengines.When the aeroengines encounter some emergency conditions, the turbine blades may suffer overheating, the temperature of which is much higher than the highest normal operating temperature. Overheating can lead to serious microstructural degradation and even premature failure of turbine blades. In this paper,the methods of overheat inspection and failure analysis were introduced, as well asthe effects of overheating on the microstructural degradation and mechanical propertiesof aeroenginesturbine blades. In addition, the damage assessment, life prediction and microstructure rejuvenation of superalloys after overheating were prospected in this paper, which provide a guidance and theoretical basis for the degradation evaluation and failure analysis of turbine blades as well as the development of new superalloys.

In this paper, the interrupted and ruptured creep tests were carried out in a novel second generation single crystal superalloy named DD11 at 1100 °C/130 MPa. The alloy exhibited typical creep curve including primary, steady, and tertiary three creep stages. The microstructural evolution at different stages of the creep were analyzed by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that the γ′ phases transform into rafted structure at the early stage of the steady creep and keep stable during the steady creep stage. As the creep goes on, the rafted structure further coarsens and the topological inversion occurs. In addition, at the primary creep, the dislocations mainly move in the γ matrix and pile up in the γ/γ′ interface since the matrix channels widen slightly. The formation of the regular interfacial dislocation networks occurs at the early stage of the steady creep. Under the low stress, the dominated deformation mechanism during steady creep stage is the climbing of the 〈010〉 type edge dislocation. Furthermore, the effect of the deformation mechanism on creep property was discussed in detail. [ABSTRACT FROM AUTHOR]

Two bicrystal specimens containing high angle grain boundary (about 20 degrees) were prepared by seed crystal method. The effect of Hf on the as-cast, heat-treated grain boundary microstructure, composition and stress rupture properties under 1100℃/100MPa was investigated in Ni-based single crystal superalloy contained Re with different contents of Hf (mass fraction:0%, 0.4%). The results show that Hf addition results in the increase of the volume fraction of (γ+γ') eutectic and MC along the grain boundary. The volume fraction of cellular recrystallization microstructure is significantly decreased after heat treatment with Hf addition. The transverse stress rupture life is observed to increase significantly under 1100℃/100MPa in the Hf-containing alloy. The stress rupture properties are closely related to the type, morphology, content and composition of the precipitation phase along grain boundary, but the obvious segregation of Hf is not observed. This study can be helpful for the understanding of Hf's role of strengthening mechanism in grain boundary in advanced Ni-based single crystal superalloy.

Anions play a significant role in the construction of metal–organic frameworks (MOFs). Anions can affect coordination between metal ions and organic ligands, and the formation of crystal structures, thereby affecting the structure and properties of MOFs. Two novel 3D porous MOFs ({[Cd3(TIPE)2(SO4)1.6(H2O)2.4]·2.8OH·6.2H2O}n (MOF-1) and {[Cd3(TIPE)2(SO4)3(H2O)2]·10H2O}n (MOF-2)) were successfully synthesized, by introducing SO42− to design and adjust their structure and properties, in which the sulfate ions not only participated in coordination but also played a bridging role. Both MOF-1 and MOF-2 exhibited high stability and strong fluorescence properties, and their fluorescence properties also changed compared to those of previously reported 2D nonporous MOF-3 ({[Cd2(TIPE)2Cl3(ACN)]·CdCl3·3H2O}n) with an identical ligand. They could also be used in combination with MOF-3 to distinguish between Fe3+ and Cr2O72− ions, due to a change in their fluorescence properties. In this work, the structure was reshaped by introducing sulfate ions, and the role and function of the sulfate ions in the structure were studied, providing a feasible idea for the design and precise regulation of MOFs. [ABSTRACT FROM AUTHOR]