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Chlorobenzene is one of the Persistent Organic Pollutants (POPs) threatening human health. It is significant to study the degradation mechanism under external electric fields. Based on the density functional theory, the physical and dissociation properties including C–Cl bond length, total energy, dipole moment, frontier orbital energy, energy gap, IR spectrum, UV-vis absorption spectrum and potential energy curve are studied under external electric fields. According to these results, it is found that the C–Cl bond length becomes longer and tends to break with the increase of external electric field and the energy gap decreases with the increase of positive as well as negative external electric field. Moreover, the dissociation barrier in potential energy curve decreases and equilibrium bond length increases with increase of positive external electric field. And when external electric field reaches 0.040 atomic units ([Formula: see text], 1 atomic [Formula: see text], the dissociation barrier disappears which means that degradation of chlorobenzene occurs under strong external electric field due to the breakage of C–Cl bond. These results provide important references for studying the degradation mechanism of chlorobenzene under strong external electric fields.

We propose an experimentally feasible scheme to produce bright six-partite continuousvariable (CV) entanglement by coupled intracavity non-degenerate parametric downconversion operating above-threshold. The six-partite entanglement properties of the output fields are theoretically analyzed according to the sufficient inseparability criterion for multipartite CV entanglement. Such compact tunable multipartite CV entanglement, generated from a coupled system, could be used in quantum communications and networks.

Two types of artificial oil‐contaminated soils (OCS) are prepared upon mixing sandy soil with water and crude oil in different proportion. OCS‐I represents the contaminated dry soil and OCS‐II the contaminated wet soil. Soil and crude oil are characterized through infrared spectroscopy and zeta potential analysis, and the OCS microstructure model has been discussed. It is speculated that the polarity petroleum components (e.g., non‐hydrocarbons) are higher in the oil layer of the neighboring soils, forming a “polarity bottom layer.” In OCS‐I, the “polarity bottom layer” is tightly adhered to soil and exhibits poor mobility. This layer is difficult to separate from soil through washing, thereby resulting in a low oil removal rate (ORR). In OCS‐II, the petroleum and soil are separated by a water film with high liquidity. During washing, the “polarity bottom layer” is easily separable from soil, thereby resulting in a high removal rate of polarity component in crude oil and high ORR as well. Based on the results of this study, it could be concluded that OCS‐I is much more difficult to be washed than OCS‐II when these two types of soils contain relatively same amount of substance content (oil, water, and other crude oil groups).

The presence of hydrogen sulfide in natural gas will reduce the calorific value of natural gas, so hydrogen sulfide in natural gas needs to be removed. Titanosilicalite zeolite is a stable porous material with good catalytic effect and has attracted much attention due to its excellent catalytic oxidation performance in the system composed of it and hydrogen peroxide. Therefore, in this paper, the removal of hydrogen sulfide in natural gas was studied by using titanosilicalite zeolite as catalyst and hydrogen peroxide as oxidant, and the mixture of hydrogen sulfide and nitrogen gas was used as the simulated gas of natural gas. The experimental results show that the titanosilicite zeolite has a good catalytic effect on hydrogen sulfide. The influence of the concentration of hydrogen peroxide, reaction temperature and pH of the initial solution in the process of removing hydrogen sulfide by titanosilicalite zeolite was studied.