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The numerical simulation method is used to study the influence of the mixing ratio of methane/hydrogen mixture on the combustion characteristics and pollutant emission characteristics of the combustor. The results show that due to the action of combustion chemical reaction, there exists a certain difference in the structure of cold and hot flow fields. The flow velocity of the hot flow field increases, and the recirculation zone becomes larger. The hydrogen content has a significant impact on the structure and temperature distribution characteristics of the hot flow field, and a central recirculation zone is formed when the hydrogen content is less than 20%, which can maintain stable combustion. When the hydrogen content is greater than 40%, the central recirculation zone disappears, the external recirculation zone is extended, and the spontaneous combustion and flashback occur to varying degrees. As the inlet air temperature increases, the spontaneous ignition phenomenon becomes more obvious, and the inlet air temperature decreases, the flashback phenomenon becomes more obvious. NOx emissions increase with the increase of hydrogen content, CO emissions decrease with the increase of hydrogen content, and CO is concentrated in the combustion zone of the main combustion stage.

In order to solve the problems of high pollutant concentration and low treatment efficiency of sewage in expressway service area, an integrated A2O-MBR reactor was used to treat the target sewage. On the basis of successful start-up of the reactor, the pollutant removal performances of A2O-MBR process under the influence of different DO, nitrification reflux ratio and C/N were studied. The results showed that A2O-MBR could obtain the best pollutant removal effect under the condition of DO mass concentration of 4 mg/L, nitrification reflux ratio of 300% and C/N of 6. The removal rates of COD, BOD5 and TP were about 90.57%, 93.75% and 93.00%. When the reactor was stable,the effluent mass concentrations of NH4+-N and SS were about 4.2 mg/L and 4.5 mg/L, respectively. The effluent indicators all met the requirements of flushing and vehicle flushing in the Reuse of Urban Recycling Water-Water Quality Standard for Urban Miscellaneous Use(GB/T 18920-2020). The integrated A2O-MBR could reduce the pollution degree of membrane components, thus reducing the maintenance and operation cost of the system, and could provide a reference for the actual engineering transformation of sewage treatment in the service area of highways.

Based on the principle of the rich-burn/quench/lean-burn (RQL) technology, a low emission combustion chamber for gas turbine was designed. The effects of different heights of quenching structure and distribution ratios of the air flow on the flow field, temperature field, and pollutant formation characteristics of combustion chamber were studied under the premise of keeping the inlet parameters of combustion chamber unchanged. The results show that the height of quenching structure and the proportion of air distribution are important parameters affecting the combustion performance of the combustion chamber. With the decrease of the height of quenching structure, the NOx emission increases at the exit of the combustion chamber. The NOx emission from combustion chamber outlet first decreases and then increases with the decrease of the proportion of air mass flow from the main combustion hole to the fired air mass flow in oil-rich areas, and an optimal proportion of air mass flow makes the NOx minimum. The production of thermal NOx is directly related to the size of the region with a temperature higher than 1 900 K and the maximum gas temperature. The designed combustion chamber has a minimum NOx emission of less than 35 mg/m3 under the studied working conditions, which achieves the emission standard of a low pollution combustion chamber.

Exploring the construction, of course, Civics of graduate students in foreign languages is to promote better the implementation of course, Civics in foreign languages. In this paper, in the context of the new liberal arts of big data, firstly, the method related to the sparrow search algorithm is described, and the parameters related to the sparrow search algorithm are optimized by using the good point set initialization and firefly update strategy. Then the basic principle of the extreme learning machine is given, and it is shown that the ELM model’s output weights are obtained using the inverse matrix solution. The ISSA-ELM algorithm model is elicited using the improved sparrow search algorithm with the extreme learning machine, and the ARE and RMSE performance validation is performed for this model using the UCI dataset. Finally, the ISSA-ELM algorithm was used to analyze and mine the indexes of the construction of the example of the postgraduate course Civics in foreign languages, including both teaching implementation and teaching content, using GZ University as an example. From the teaching implementation, the percentages of A, B, C and D evaluations are 16.12%, 18.44%, 18.12% and 47.32%, respectively. Regarding teaching content, the percentages of A, B, C, and D evaluations were 49.65%, 22.95%, 16.5%, and 10.89%, respectively. This indicates that the construction of the course Civics for graduate students in foreign language disciplines in the context of the new liberal arts is not optimistic, and effective reforms in teaching implementation and content are needed afterward.