The genus Fagopyrum (Polygonaceae), currently comprising 15 species of plants, includes three important buckwheat species: Fagopyrum esculentum (F. esculentum) Moench. (common buckwheat), Fagopyrum tataricum (F. tataricum) (L.) Gaertn. (tartary buckwheat) and Fagopyrum dibotrys (F. dibotrys) (D. Don) Hara. (perennial buckwheat), which have been well explored due to their long tradition of both edible and medicinal use. This review aimed to present an up-to-date and comprehensive analysis of the phytochemistry and pharmacology of the three Fagopyrum buckwheats. In addition, the scope for future research was also discussed. All available references included in this paper were compiled from major databases, such as MEDLINE, Pubmed, Scholar, Elsevier, Springer, Wiley and CNKI. A total of 106 compounds isolated from three Fagopyrum buckwheats can be mainly divided into six classes: flavonoids, phenolics, fagopyritols, triterpenoids, steroids and fatty acids. Flavonoids and phenolic compounds were considered to be the major active components. Considerable pharmacological experiments both in vitro and in vivo have validated that Fagopyrum buckwheats possess antitumor, anti-oxidant, anti-inflammatory, hepatoprotective, anti-diabetic activities, etc. All reported data lead us to conclude that Fagopyrum buckwheats have convincing medicinal potential. However, further research is needed to explore its bioactive constituents, the relationship to their structural activities and the molecular mechanisms of action.

In large-scale power system, low frequency power oscillation is becoming a serious threat to the power system operation. Analysis of low frequency oscillation includes model-based method and ambient-excitation-based method. Based on the investigation of the related recently-published papers, this paper presents a survey of ambient-excitation-based method. Firstly, the fundamental principle and underlying theory of ambient-excitation-based method are summarized. Furthermore, several ambient-excitation-based methods are categorized and their characteristics are introduced.

For the purpose of powder injection molding of SiCp/Cu composite, it is studied that the reasonable choice of powder and binder, the determination of powder loading and the pretreatment of powder. Fabrication of feedstock is carried out by experiment, in which some issues are studied such as the temperature of mixing, the mixing sequence, the control of mixing uniformity and the control of oxidation of copper powder during the mixing. The results show that the mixing effect of powder with binder is well; the SiC particles are uniformly distributed in the Cu matrix and no obvious agglomeration of the particles exist.

A SiCp/Cu composite with excellent performance is prepared by using the advanced powder injection molding technology. The microhardness and tensile strength of the composite are detected, and the surface microstructure and the tensile fractures are observed. The results show that SiC particles are uniformly distributed in Cu matrix and excellently bonded with the Cu matrix. With the increase of the SiC content, the microhardness of the composite is increased while the tensile strength is increased first and then decreased. A crackle source of the composite for tensile fracture mainly includes two kinds: cracking of the Cu matrix in vicinity of the SiC particles and debonding of an interface of the SiC particles and the Cu matrix.

With the speed up of the train, higher performance demands are put forward to the materials which have friction function. The friction materials produced by power metallurgy technology have a lot of advantages, such as good wear resistance, better thermal conductivity, bearing high lord, work reliably and so on. So they are used widely in the fields such as auto industry, aerospace and so on. The application of metal powder metallurgy technology in preparation friction materials of railway vehicles was researched in this paper, such as brake-shoe, brake lining of train braking, pantograph slide of electric locomotive, electrify boots slider of the maglev train and so on. This kind of friction material has superior performance and better prospects.