A series of nanocomposites of ionic liquids (ILs) were prepared via a modified sol-gel method. The ILs were physically confined in mesoporous silica gels with 5-40% content. ILs from imidazolium, thiophenium and ammonium with different anions were prepared and used. Characterization using the Brunauer-Emmett-Teller (BET) method, Fourier transform infrared (FT-IR) spectroscopy, temperature-programmed desorption (TPD), differential scanning calorimetry (DSC), inverse gas chromatography (IGC), temperature-controlled Raman and fluorescence emission spectroscopies was conducted to explore any confinement effects. BET results showed that, depending on the ILs and their contents, the average pore diameter of the pure silica gel was 3-12 nm after the confined ILs were removed completely. It was suggested that ILs aggregated on the nanoscale in the mesoporous silica gel. In comparison with bulk ILs and ILs coated onto silica gels (IL/sg), IL nanocomposites (IL-sg) displayed remarkably low specific heat capacities (C(p) was in the range 0.3-1.2 J g(-1) K(-1)), disordered vibrational conformations (without phase transitions in the range -100-200 degrees C), greater interactions with hydrocarbon solutes (adsorption capacities of 0.3-0.4 g per 100 g for confined ILs with CO(2) gas), and greatly enhanced fluorescence emission (up to 200 times stronger than bulk ILs). Furthermore, Based on the specific solubility of different compounds, the nanocomposites could also be applied to the separation of CO(2) from CO(2)/N(2) mixtures and thiophene from thiophene/octane mixtures.

A simple, clean, safe, and reproducible catalyst system, polymer-supported nanogold, was successfully developed for the fixation of CO2 to cyclic carbonate and for the carbonylation of amines to disubstituted ureas with unprecedented catalytic activity (TOF > 50 000 mol/mol/h and TOFP approximately 3000 mol/mol/h, respectively). To the best of our knowledge, it was the first to report that nanogold catalysts have exclusive catalytic activity for activation of carbon dioxide, and that the catalytic activity of the polymer-immobilized nanogold catalysts could be controlled by the particle size of the nanogold.

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Interpretation of high-resolution two-dimensional (2D) and three-dimensional (3D) seismic data collected in the Qiongdongnan Basin, South China Sea reveals the presence of polygonal faults, pockmarks, gas chimneys and slope failure in strata of Pliocene and younger age. The gas chimneys are characterized by low-amplitude reflections, acoustic turbidity and low P-wave velocity indicating fluid expulsion pathways. Coherence time slices show that the polygonal faults are restricted to sediments with moderate-amplitude, continuous reflections. Gas hydrates are identified in seismic data by the presence of bottom simulating reflectors (BSRs), which have high amplitude, reverse polarity and are subparallel to seafloor. Mud diapirism and mounded structures have variable geometry and a great diversity regarding the origin of the fluid and the parent beds. The gas chimneys, mud diapirism, polygonal faults and a seismic facies-change facilitate the upward migration of thermogenic fluids from underlying sediments. Fluids can be temporarily trapped below the gas hydrate stability zone, but fluid advection may cause gas hydrate dissociation and affect the thickness of gas hydrate zone. The fluid accumulation leads to the generation of excess pore fluids that release along faults, forming pockmarks and mud volcanoes on the seafloor. These features are indicators of fluid flow in a tectonically-quiescent sequence, Qiongdongnan Basin.