Different morphology CeO₂ was used as a catalyst to catalyse the synthesis of trimethylene carbonate from CO₂ and 1,3?propanediol.The structure and composition of cerium oxides were characterized by SEM, TEM, XPS and XRD. The results showed that the yield of trimethylene carbonate was up to 72.5% at 130 ℃ for 4 h when using the rod?shaped cerium oxide as catalyst and 2?cyanopyridine as dehydrating agent. R?CeO₂ has a higher number of defect sites and an suitable specific surface area, The average particle size is small and it has moderate number of Lewis acidic sites. Based on this, the substrate range was expanded, and the experimental results showed that both five?membered cyclic carbonates and six?membered cyclic carbonates could be obtained in good yields.

The BaTiO₃?TiO₂ composites were prepared by using hydrate barium hydroxide (Ba(OH)₂·8H₂O) and titanium dioxide (TiO₂) as raw materials with soft chemical hydrothermal method at 120 ℃ and different Ba/Ti molar ratios.The structure of the prepared composites with different Ba/Ti molar ratios was analyzed by X?ray diffraction (XRD),scanning electron microscopy (SEM),and UV?visible absorption spectroscopy (UV?Vis),the degradation effect of the complex on the simulated degradation pollutant,rhodamine B (RhB) was investigated.The results indicate that the BaTiO₃?TiO₂ composites obtained at a Ba/Ti molar ratio of 0.50 have an excellent catalytic effect for the degradation of rhodamine B (RhB) during the simulation of dye wastewater degradation.Meanwhile,more active sites formed at the Ba/Ti molar ratio of 0.50, which facilitated the photocatalytic reaction.

Given the deep burial depth,high temperature and high pressure, significant heterogeneity of the deep gas reservoirs in the southern margin of the Junggar Basin,the temporary plugging and diverting stimulation technology with stratification and segmentation was used to achieve efficient stimulation and improve the producing degree of those reservoirs.The plugging of fractures and perforations by temporary plugging agents under the high temperature of 140~180 ℃ was experimentally investigated,and the degradation rates and pressure?bearing capacities of five temporary plugging materials were evaluated respectively.The results show that the commonly used temporary plugging materials will soften under a high temperature and tend to flow with the carrying fluid under the displacement pressure difference, resulting in a decreased pressure?bearing capacity of the temporary plugging section and the loss of plugging effect. A temporary plugging material with a pressure?bearing capacity of 30.00 MPa at 180 ℃ was selected, and its field application results showed that the temporary plugging improved production significantly.

Shape memory polymer (SMP) and self?healing polymer (SHP) as the representative of "smart" polymers have become the most dynamic research direction in this field,among which photosensitive SMP and SHP have been received wide attentions by industry and academia.This paper reviews the basic principles of photosensitive SMP and SHP, and classifies this type of polymers into reversible photochemical reaction SMP,photothermal SMP,photodimerization reaction SHP,photocrosslinking reaction SHP,and bifunctional SMP/SHP by referencing the most important and representative literature reports in recent years.