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To enhance the performance of activated carbon (AC) for elemental mercury removal, a kind of AC was modified by nonthermal plasma (NTP) and the effects of the modification of the atmosphere (N2, O2, air, and HCl) were investigated by adsorption and desorption experiments. The physical and chemical properties of original and modified ACs were characterized by Brunauer–Emmett–Teller, scanning electron microscopy with energy-dispersive spectroscopy, and X-ray photoelectron spectroscopy (XPS). The results showed that better mercury removal performance of ACs was obtained after modifying by NTP in air, O2, and HCl. The mercury removal efficiency of AC–air, AC–O2, and AC–HCl was obviously enhanced compared to the raw AC and AC–N2 attributed to the large increase of oxygen-containing functional groups [CO and C­(O)–O–C] occurring on the AC surface. AC treated in HCl could form C–Cl groups, which were beneficial to improve its oxidizing ability. In addition, stronger etching and cracking on the AC surface during NTP modification in an O2 or a HCl atmosphere were found to decrease its specific surface area and micropore volume, resulting in an adverse effect on mercury removal. It was found that the desorption peaks at 290 and 340 °C of the adsorbed AC samples corresponded to carbonyl groups (CO) and ester groups [C­(O)–O–C], respectively, which were verified by combining the results of XPS and temperature-programmed desorption experiments.

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The aim of this study was to ascertain the evolution of Cr, Cu, Mn, and Zn during the composting process of chicken manure and their integrated potential ecological risk. This study detected the total amounts of Cr, Cu, Mn, and Zn in 4 samples collected at four different stages in the composting workshop of an intensive chicken farm in Chengdu, China. Furthermore, the chemical fractionation of the four heavy metals was analyzed by the BCR (European Community Bureau of Reference) three-step sequential extraction procedure for each sample. At last, the integrated potential ecological risk of Cr, Cu, Mn, and Zn in the compost at four different stages was evaluated by the procedure of potential ecological risk assessment based on its results of chemical fractionation of Cr, Cu, Zn, and Mn. During the composting process, the total amounts of Cr, Cu, Zn and Mn presented an increasing trend, significantly. Nevertheless, the residual fraction (Res-F) percentage of Cr, Zn, and Cu increased, and the acid extractable fraction (Aci-F) percentage of Mn decreased. The value of integrated potential ecological risk of the four heavy metals in the final product was 9.91. These results indicated the integrated potential ecological risk of the four heavy metals is low. This study provided a support on the promotion and utilization of compost for the intensive chicken farms in China.

The construction of emerging engineering is an important content for higher engineering education in China in the new era. The emerging engineering requires the renewal of the ideas and model of talents cultivation. In view of this, establishing a suitable multi-dimensional evaluation system for teaching quality in Chinese colleges and universities is one of the important works under the background of emerging engineering. In the study, the matters needing attention in the construction of the multi-dimensional evaluation system for teaching quality (MESEQ) were analyzed. Then, MESEQ was established, which consisted of 7 primary indexes and 33 secondary indexes. At last, the rationality and the considerations of the application of MESEQ were analyzed. In general, this study constructed an effective MESEQ under the background of emerging engineering. The MESEQ established in this study can provide a guarantee for the training of high-quality and high-level engineering talents in the new period.