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The shield tunnel boring will produce certain disturbance to the ground, causing surface settlement and uplift deformation. In order to predict the surface settlement caused by the double-bore tunnel beneath the existing road and through the fine sand stratum, a double-bore Peck formula was established, relying on the shield tunnel project of Xiong'an-Daxing international airport express line, and combined with the engineering monitoring data. The results show that, for the project where the left and right lines successively pass through the existing roads, the surface settlement of the section exhibits a "W" shape, and the axial settlement of the two tunnels is the largest. When the latter line is bored through the same section, it will increase the surface settlement of the first boring. Based on Peck's formula, combined with the measured data, a two-bore Peck's formula is established to predict the surface settlement of the section when the two bores penetrate he existing road and cross the fine sand stratum. This provides a certain theoretical basis for the tunneling projects in similar strata and engineering. [ABSTRACT FROM AUTHOR]

Explains the main sources and types of air pollutants in automobiles, and introduces methods to evaluate the effect of automobile air filters on the purification of the above-mentioned automobile air pollutants, and the purification effects of existing automobile air filter products on the market Evaluate and discuss its purification level to provide a theoretical basis for the future formulation of relevant specifications.

Hydroxylamine (NH2OH) and nitrite (NO2-) represent pivotal nitrification intermediates that substantially govern soil abiotic N2O production. Yet, the intricate factors influencing the abiotic formation of N2O from chemical reactions involving NH2OH and NO2- remain uncertain. This study was designed to reveal the impacts of land use type and parent material on soil abiotic N2O production in response to NH2OH and NO2- amendments. Our investigation revealed that land use type exerted no significant influence on abiotic production of N2O with NH2OH and NO2- addition. Nevertheless, the parent material exhibited a notable (P < 0.01) effect on N2O production intrigued by NH2OH addition. Specifically, a markedly higher abiotic N2O production from NH2OH was observed in soils developed from Quaternary red clay than those derived from granite. Subsequent analysis demonstrated that the soils originating from Quaternary red clay displayed significantly higher manganese (Mn) content in comparison to those originating from granite. This finding consistently aligns with the close correlation between the abiotic N2O production via chemical oxidation of NH2OH and Mn content of soil. Furthermore, the site preference (SP) values for N2O arising from NH2OH and NO2- addition were 25–30 ‰ and around 20 ‰, respectively, aligning with the expected ranges characterizing ammonia oxidation and chemodenitrification processes. Our findings provide valuable insight into the distinct influence of parent material on soil abiotic N2O production via chemical oxidation of NH2OH, contributing to a better understanding of the underlying mechanisms, and highlight the significance of soil factors in regulating abiotic N2O production within soil ecosystems. [ABSTRACT FROM AUTHOR]

The magnitude of negative environmental impacts generated by food production means it is now imperative we develop food systems in a way that can actively support the recovery of degraded ecosystems, while also meeting increasing demands for food and livelihoods. Aquaculture, when it utilizes the right practices and species and occurs in the right places, can strike this balance, enabling food production that supports the health of aquatic ecosystems. To ensure the efficacy of this approach, however, a clear, common understanding of the ways in which this industry can achieve this outcome is needed. This paper highlights a definition of "restorative aquaculture", identifies global principles for the use and development of restorative practices, and identifies needs for information, data, and tools that, if addressed, would greatly expand our understanding of the ways in which aquaculture and restorative activities can have positive environmental outcomes. This guidance was developed by a working group of representatives from global aquaculture, environment, economic and academic organizations. It can assist industry and government in making decisions about sustainability as well as restoration and rehabilitation strategies that intersect with aquaculture. [ABSTRACT FROM AUTHOR]