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Over the past few decades, the excessive use of pesticides has resulted in serious environment pollution, and residual pesticides prompt significant concern regarding their potential harm to both the ecological security and human health. In this study, KOH activated crayfish shell biochar (KBC) was successfully prepared and used to effectively remove acetamiprid (ACE) and triadimefon (TDM) from aqueous solutions. Batch experiments results indicated that, the adsorption process of ACE was predominantly by chemical reaction and controlled by multiple mechanisms, and ACE adsorption was a thermodynamically spontaneous and exothermic reaction. The KBC exhibited exceptional adsorption performance in removing ACE with a maximum adsorption capacity of 40.41 mg g−1. A superior adsorption capacity toward both ACE and TDM over KBC could be achieved at lower concentration levels, and KBC exhibited good reuse for the removal of ACE and TDM. Different adsorption models and characterization results revealed the adsorption mechanism of ACE and TDM by KBC, including van der Waals forces, pore filling, hydrogen bonding, and π-π electron donor-acceptor interactions. These findings suggested that KBC was an excellent adsorbent for removing pesticide-contaminated water.

Water supply pipeline system is a key issue in urban lifeline engineering, and the seismic assessment for the system damage is of significant importance. In this study, method of seismic damage assessment on underground water supply pipeline is introduced. With emphasis on the uncertainties of earthquake level, ground condition, soil-pipe interaction and capacity to resist pipe deformation in longitudinal direction, the check point method is applied to the reliability study of water pipeline, and a case study is presented to show the implementation of the proposed model.

Concrete arch dams are critical structures, the failure of which would lead to catastrophic effects on a regional scale. Considering the uncertainty characteristics of earthquake and the self-adjustment of inner force of arch dams, it’s necessary to investigate the seismic performance index of arch dam for holistically evaluating the seismic safety of arch dam-foundation system subjected to high intensity seismic excitations. By considering the contraction joints movement and concrete material nonlinearity, a series of dynamic response-history analyses of arch dam were carried out under increasing levels of earthquakes. Based on these analyses, the performance index of crest deformation is recommended for the seismic safety assessment of arch dam. And several performance stages of seismic response including the opening of contraction joints and the distribution of concrete damage are also investigated.