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During a survey of soil fungi collected from Yunnan Province, China, two new species of Exophiala, E. yunnanensis and E. yuxiensis, were isolated from the soil of karst rocky desertification (KRD). The DNA sequences of these respective strains, including internal transcribed spacers (ITS), large subunit nuclear ribosomal RNA (LSU rRNA), partial small subunit (SSU) and β-tubulin (tub2) were sequenced and compared with those from species closely-related to Exophiala. Exophiala yunnanensis differs from the phylogenetically closely related E. nagquensis and E. brunnea by its smaller aseptate conidia. Exophiala yuxiensis is phylogenetically related to E. lecanii-corni, E. lavatrina and E. mali, but can be distinguished from them by its larger conidia. Full descriptions, illustrations and phylogenetic positions of E. yunnanensis and E. yuxiensis were provided.

Pest migration has the characteristics of large scale and strong suddenness, which will lead to the outbreaks of pests and diseases, the decline of grain yield, and considerable economic losses. Entomological radar is an effective means of monitoring migratory pests. However, the Radar Cross Section (RCS) of an insect target is small, whereas the echo power is weak. High detection probability will result in a high false alarm probability. In the data association step of target tracking, the association error occurs due to the influence of false measurement. By utilizing the amplitude difference between the target and noise, the amplitude information-assisted tracking algorithm can effectively improve the recognition degree toward the target and noise and improve the tracking performance. However, the RCS fluctuation model of the target is needed as prior information to calculate the amplitude likelihood ratio. Therefore, in this paper, the insect RCS fluctuating characteristics are analyzed based on Ku-band entomological radar experiment data. The results show that gamma distribution can fit well the RCS probability distribution of the insect target. On this basis, we derive the amplitude likelihood ratio of the gamma fluctuation target in Gaussian white-noise background. By analyzing the simulation results and performance under different signal-to-noise ratios, measurement noises, and fluctuation model parameters, compared with probabilistic data association filter, the RCS feature-aided tracking algorithm can effectively improve the insect target tracking accuracy.

Entomological radar is an effective means of monitoring insect migration, and can realize long-distance and large-scale rapid monitoring. The stable tracking of individual insect targets is the basic premise underlying the identification of insect species and the study of insect migration mechanisms. However, the complex motion trajectory and large number of false measurements decrease the performance of insect target tracking. In this paper, an insect target tracking algorithm in clutter was designed based on the multidimensional feature fusion strategy (ITT-MFF). Firstly, multiple feature parameters of measurements were fused to calculate the membership of measurements and target, thereby improving the data association accuracy in the presence of clutter. Secondly, a distance-correction factor was introduced to the probabilistic data association (PDA) algorithm to accomplish multi-target data association with a low computational cost. Finally, simulation scenarios with different target numbers and clutter densities were constructed to verify the effectiveness of the proposed method. The tracking result comparisons of the experimental data acquired from a Ku-band entomological radar also indicate that the proposed method can effectively reduce computational cost while maintaining high tracking precision, and is suitable for engineering implementation.

A multilayer three-dimensional (3D) structure made of hydrophobic stainless steel mesh has been designed for in situ continuous oil/water separation. The hydrophobic stainless steel mesh was prepared via a facile and environmental friendly method by etching with FeCl3 solution and coating with n-octadecylthiol. The as-prepared mesh allows oils (gasoline, diesel oil, engine oil) and organic solvents (hexane, liquid paraffin) to pass through and repels water. A separation device equipped with the multilayer 3D structure can continuously separate the aforementioned oils from oil–water mixtures. The separation efficiency of continuous separation is more than 99.0 wt % and shows little decrease after 10 cycles.

A continuous in situ oil–water separation technique for cleanup of oil spills has been designed using surface modified polyurethane (PU) sponges as sorbents. By connecting PU sponges to a vacuum pump, they can continuously separate various kinds of oil and organic pollutant, including engine oil, diesel oil, peanut oil, liquid paraffin and hexane, from the surface of water with negligible water take-up. The sorbents used in the technique were prepared by dip-coating commercial PU sponges with TiO2 sol and n-octadecylthiol successively. After surface modification, the sponges change from hydrophilic to superhydrophobic and superoleophilic surface with the water contact angle measured to be 152°. The as-prepared sponges absorb a broad variety of oils and organic solvents with high oil absorption capacity (80–110 g g−1) and negligible water take-up at both static and dynamic conditions. The success of the continuous in situ oil–water separation technique is based on the excellent oil–water selectivity and oil adsorption capacity of the modified sponges.

A sorbent for oil spill cleanup was prepared through a novel strategy by treating polyurethane sponges with silica sol and gasoline successively. The oil sorption capacity, oil/water selectivity, reusability and sorption mechanism of prepared sorbent were studied. The results showed that the prepared sorbent exhibited high sorption capacity and excellent oil/water selectivity. 1g of the prepared sorbent could adsorb more than 100 g of motor oil, while it only picks up less than 0.1 g of water from an oil-water interface under both static and dynamic conditions. More than 70% of the sorption capacity remained after 15 successive sorption-squeezing cycles, which suggests an extraordinary high reusability. The prepared sorbent is a better alternative of the commercial polypropylene sorbent which are being used nowadays.