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Gastrointestinal cancer (GIC), including gastric cancer and colorectal cancer, is a common malignant tumor originating from the gastrointestinal epithelium. Although the pathogenesis of GIC has not been fully elucidated, angiogenesis is recognized as the key pathological basis for the growth, invasion and metastasis of cancer cells, and GIC angiogenesis is closely related to vascular endothelial growth factor family, hypoxia-inducible factor family, fibroblast growth factor family and matrix metalloproteinase family. Recently, many natural products have shown a wide range of pharmacological biological activities against GIC. In this review, the effects and mechanisms of natural compounds on the angiogenesis of gastric and colorectal cancer were summarized. The results show that some natural compounds, especially gallic catechin gallate, astragaloside and curcumin, can effectively inhibit angiogenesis; the HIF-1α/VEGF, COX-2/PGE2, HGF/c-Met and PI3K/Akt/mTOR are involved in these inhibition effects. This review examines the anti-angiogenesis potential of natural products in the GIC treatment and provides clues to the development of vascular targeted agents.

High-capacity anode materials are widely studied for rechargeable batteries, which have the capability of storing more Li+ ions per formula. However, they normally experience large volume expansion and suffer inferior cycling stability. Herein, we propose pea-pod structured V2O3 yolk-shell microspheres@N, S co-doped carbon fiber network as an excellent anode material for lithium ion batteries. The prepared vanadium dioxide precursor is uniformly embedded into the carbon fibers by electrospinning treatment and further converted into V2O3 yolk-shell microspheres during the calcination process. The conductive carbon fiber framework which links V2O3 microspheres enhanced the electrical conductivity and structural stability significantly. Moreover, the co-doped N and S atoms derived from polymer could produce extrinsic defects, thereby improving Li+ diffusion and electrochemical active sites. When used as anodes for lithium ion batteries, the composite exhibits a high reversible capacity (793.7 mA h g−1 after 100 cycles at 100 mA g−1), excellent rate performance and cycle stability.

Based on XRD, SEM and TEM studies of the obtained Li (Ni0.67Co0.33) O2 phase from sintering, the results show that the space group of the phase is R 3 ¯ m , which belongs to the rhombohedral lattice, and there are observed many twins with 1 1 ¯ 0 4 ¯ as twining plane in the crystal. When Li (Ni0.67Co0.33) O2 phase is forming twins with 1 1 ¯ 0 4 ¯ as twinning plane, the octahedrons in the twinning plane need not to make any adjustment. At the same time, the 1 1 ¯ 0 4 ¯ interface f is close-packed plane for Li, (Ni, Co) and O atoms, moreover, the interface energy maybe the lowest if the 1 1 ¯ 0 4 ¯ plane is used as an interface. Crystallographic analysis showed that when the twins with 1 1 ¯ 0 4 ¯ as twinning plane were formed in Li (Ni0.67Co0.33) O2 phase, orientation relationship between the two twin sub-grains can also be considered as two variants of the orientation domain.

Powder packing behavior plays an important role in determining sintering ability of powder and the resultant performance of materials. In this study, a novel powder packing theory with bimodal particle size distribution is proposed by considering the loosening effect, wall effect and wedging effect. This theory is applied in PM nickel base superalloy by using mixture of coarse particles and fine particles. Microstructures of alloy sintered by vacuum hot pressing (HP) are observed by optical microscope (OM) and electron backscatter diffraction (EBSD). The prediction result by this theory is in good agreement with the experimental results. The enhanced sintering ability of powder containing appropriate fractions of coarse particle and fine particle is ascribed to the filling of fine particles to the voids between coarse particles, which enhanced the density of sample after sintering. Tensile behavior and the fracture morphology of alloys with various particle distributions are analyzed in details, suggesting the higher reliability of the present theory.

Carbon films with a well-developed meso-porosity were synthesized directly by the carbonization of sulfuric-acid-treated P123 triblock copolymer/silica nanocomposite films, which were prepared from dip-coating technique through an association of sol–gel and evaporation-induced self-assembly process, and the residual silica was removed subsequently via HF-etching. P123 was employed as both structuring agent for self-assembly of tetraethyl orthosilicate and carbon precursor. The sulfuric acid solution was used as a catalyst for cross-linking of P123/silica in order to improve the carbon yield for the continuity of carbon films. Investigations by Field emission scanning electron microscopy (FESEM), X-ray diffraction, nitrogen adsorption measurement and transmission electron microscopy (TEM) indicate that the hybrid carbon/silica mesoporous films are preserved perfectly after the carbonization. When the silica is removed by acid treatment, continuous carbon films with an ordered symmetric structure are still kept well. The carbon films obtained are composed of carbon nanotubes with the diameter of around 6 nm, and the lengths of nanotubes affiliating with each other vary from about 100 nm to several micrometers, which were measured by FESEM and TEM.

Two types of twins and an orientation domain (orientation twin) were found in CaMgSi particles formed in a Mg–Ca–Si alloy by transmission electron microscopy. The two types of twins were shown to be a (1 0 2) twin with the (1 0 2) plane serving as the twinning plane and a (0 1 1) twin with the (0 1 1) plane serving as the twinning plane. In addition to the frequently observed two-fold twin, two different three-fold twins were also observed in the (1 0 2) twinned CaMgSi particles; their crystallographic features are discussed in detail. The boundaries of both the (1 0 2) and (0 1 1) twins were found to be coincident with the twinning plane. The orientation domains were formed by one segment rotating 60° about the [1 0 0] axis relative to the other. The possible formation mechanisms of the twins and orientation domain are discussed based on a crystallographic consideration.

Piezochromism describes a tendency of certain materials changing colors when they are subjected to various pressure levels. It occurs particularly in some polymers or inorganic materials, such as in palladium complexes. However, piezochromism is generally believed to work at high pressure range of 0.1-10 GPa. This research work focused on unique piezochromism responses of the nanometer voids formed by the 5-20 nm inorganic ISOH nanometer powders. It was discovered that microstructures of the nanometer voids could change color at very low pressures of only 0.002-0.01 GPa; its sensitivity to pressure was increased by tens of times. It is believed that the uniform microstructures of nanometer powders contributed to the material's high sensitivity of piezochromic phenomena. One factor which quantum optical change caused by nanometer voids affected the quantum confinement effect; another is surface Plasmon Resonance of great difference dielectric property between conductive ITO powder and insulation hydroxide.