Surfactant-promoted methane hydrate formation during the past 2–3 decades has been reviewed, aiming toward achieving a comprehensive evaluation on the current research status and effective guidance on the research prospects.

A kind of difunctional catalystalkyl ester sulfonate copper, which not only has the catalytic center but also has the hydrogen precursor structurewas synthesized for the first time. It has been used for catalytic aquathermolysis of super heavy oils both in the laboratory and field. The laboratory experimental results show that, although its viscosity is about 1.81 × 10 5 mPa•s at 70 °C, the viscosity of heavy oil could be reduced by 90.72% using 0.3 wt % catalyst at 240 °C for 24 h, with 10.12% in conversion of heavy content to light content. To evaluate the catalyst's high performance, the structure and group compositions of the oil were characterized by Fourier transform infrared (FT-IR), elemental analysis (EL), gel permeation chromatrography (GPC), 1 H nuclear magnetic resonance ( 1 H-NMR), and gas chromatography−mass spectrometry (GC−MS). It is found that the catalyst can not only enhance the viscosity reduction of heavy oil, but also remove some heteroatoms from its molecules, finally make the flow properties better and the quality upgrading. In field tests of the F10223 well of the Xinjiang Oilfield, the preliminary result has also proved the evident effects of the catalyst. Additionally, in view of the environmentally friendly and low toxicity of the catalyst, it will be beneficial for supporting a vast array of environmental, health, and safety (HSE) standards and is likely to have some good application prospects.

Low-valent vanadium oxide nanostructures have been synthesized in large quantities using commercial V2O5 powder as the precursor by a facile reduction method. The crystal structures and morphologies of vanadium oxide nanostructures can be adjusted by altering the concentrations and types of reductants. VO2(B) nanostructures are fabricated using oxalic acid as the reductant. VO2(B) nanobelts with widths of 80-150 nm, thicknesses of 20-30 nm, and lengths up to several micrometers can evolve to olive-like nanostructures composed of nanosheets with thicknesses of several nanometers and lateral dimensions of several micrometers as the concentration of oxalic acid increases. H2V3O8 nanobelts with widths of 200-300 nm, thicknesses of 10-20 nm, and lengths up to several 10s of micrometers are obtained under the reduction of V2O5 powder with ethanol. The belt-shaped morphologies of H2V3O8 are not affected by the concentration of ethanol.

YVO4 and YVO4:Eu3+ nanobelts and polyhedral micrometer crystals have been successfully synthesized by hydrothermal treating the mixture of NH4VO3 and Y(NO3)3 without the aid of any surfactants and templates. The thickness, widths, and lengths of YVO4 nanobelts are about 40−60 nm, 110−180 nm, and several micrometers, respectively. Such nanobelts can grow along the [010] direction. YVO4 polyhedral micrometer crystals have flat faces and regular shapes. The influences of pH values on the morphologies of YVO4 have been investigated. The photoluminescence properties of YVO4:Eu3+ nanobelts and polyhedron microcrystals have been discussed.