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An innovative strategy for synthesizing novel dual-reaction-center (DRC) catalysts from chicken manure (CM) biochar to purify wastewater that contained emerging contaminants (ECs) is proposed to synchronously address the release of ECs and improper disposal of livestock manure. A series of characterization techniques reveal the formation of a special C-O-Ca bond bridge (cation-π) structure on resourcelized CM nanosheets (RCM NSs). RCM NSs exhibit distinct selectivity and anti-interference capability for various ECs removal in complex matrices, and the water purification system remains stable after 1735 hours (equivalent to 3470 cycles) of operation. Density Functional Tomography (DFT) calculations reveal that trace of peroxymonosulfate as an inducer initiates the continuous donation of electrons from electron-rich ECs and the C-O-Ca bond bridges provide a favorable pathway for electron transfer, which facilitates the electron capture effect of dissolved oxygen in the system. This study provides a novel strategy to convert livestock manure into DRC-catalysts for developing energy-saving and high-efficiency environmental remediation technologies. Highlights: • The chicken manure biochar was converted into a water purification catalyst through a graphitization process. • Resourcelized catalyst RCM NSs had superior removal capability for various ECs triggering by trace of PMS. • RCM NSs could quickly eliminate ECs and simultaneously drive NOM removal, even with NOM interference. • The key role of dissolved oxygen for water purification was illustrated in RCM NSs system. [ABSTRACT FROM AUTHOR]

Anti-dip rock slopes are widely developed and distributed in the Three Rivers basin in China, and associated deformation and damage phenomena are especially prominent among slope problems, including composite toppling under internal and external dynamic coupling. Through a model test of similar material, the entire sliding-toppling composite deformation and failure process of an anti-dip rock slope under an external load is studied. The macroscopic deformation, rock displacement, and maximum flexural surface in the process of slope deformation and failure are analyzed, and the composite toppling failure mechanism and evolution law of the anti-dip layered rock slope under various stress conditions are revealed. A physical model is validated by inverting the Zongrong landslide through discrete element numerical simulations, and the anti-dip rock slope with composite toppling deformation is divided. The research results show that (1) block toppling-shear slip damage occurs in the toe area, which is accompanied by the maximum flexural surface, the lower rock layer shows multilayer flexural toppling, the upper rock layer is relatively stable, and the slope is zoned according to the Df value; (2) deep dissection of the river is a precondition of such slope toppling deformation, while rainfall was a predisposing factor for the Zongrong landslide; and (3) the failure mode of the anti-dip rock slope under an external load is generalized into five main stages, shear slip of the slope toe → block toppling of the slope toe → maximum flexural surface → deep flexural toppling of the rock stratum under the flexural surface → penetration of the main fracture surface, and verified using the discrete element numerical model. [ABSTRACT FROM AUTHOR]

Rural pollution is largely caused by the accumulation of waste biomass, such as livestock manure and crop straw, which is extremely difficult to dispose of due to the simultaneous need to non-destructively treat metal and organic matter. Untreated fecal waste fluxes have contributed to more than 870,000 sanitation-related deaths annually worldwide. The existing disposal methods are accompanied by large amounts of energy and resource consumption and GHG emissions, which are not conducive to achieving the UN Sustainable Development Goals (SDGs). Herein, we pioneer a new approach to sustainable resource utilization by subjecting unprocessed livestock manure to a Dual-Reaction-Center (DRC) Fenton-like catalyst directly through the ordered bonding of intrinsic metal-organic species via an in situ 2-stage calcination-annealing process with zero emissions and zero pollution. The directional electron transfers along with the generated metal cation–π interactions during the resourcelized process led to the formation of electron-rich/-poor microregions. Through triggering by a small amount of hydrogen peroxide (H2O2), the removal of refractory pollutants reaches 100% within a very short time in this system, which also shows a long-term purification effect on actual wastewater, accompanied by the utilization of intrinsic energy from the pollutants and dissolved oxygen. This study is expected to advance the resource utilization of rural waste and the sustainable development of environmental factors. [ABSTRACT FROM AUTHOR]

Purpose: Application of functional organisms in soil organic amendments has the potential to accelerate organic matter decomposition and stimulate C cycling. In this study, a short-term (a year) field experiment was conducted to investigate the collaborative effects of earthworms and phosphate-solubilizing bacteria on C accumulation in pig manure-amended soil. Materials and methods: A field experiment was conducted with six treatments established. The first three treatments, including control (CK), pig manure (Pm), and pig manure + slurry (Pm + S), were set up to evaluate the influences of pig manure on soil C accumulation. The other three treatments, including manure + slurry + earthworms (Te), manure + slurry + phosphate-solubilizing bacteria (Tb), and manure + slurry + earthworms + bacteria (T(e + b)), were set up to investigate the collaborative effects of functional organisms on soil C cycling. The Pm + S treatment was chosen as the control (T) for this purpose. Results and discussion: The results showed that the soil C pools did not increase significantly under the manure treatment. In contrast, an integrated application of manure, slurry, earthworms, and bacteria significantly increased the various C fractions, such as SOC and humin, indicating a rapid and positive effect of earthworms and bacteria on C accumulation. Besides, C sequestration by the integrated application was as high as 1.35 Mg C ha soil, half of which was stabilized. Conclusions: The T(e + b) was an efficient strategy to sequestrate and stabilize SOC in arid hillside soils. The bacteria increased the labile OC, especially microbial biomass C, while the earthworms were apparently essential for the increase in stable OC. [ABSTRACT FROM AUTHOR]

We evaluated the influence of the biodegradable chelant ethylenediamine disuccinic acid (EDDS) on plant uptake of polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and Cu by corn from electronic waste (e-waste)-contaminated soil. The highest concentration and highest total uptake of Cu in corn were observed in the treatment with 5 mM EDDS, which resulted in a 4-fold increase of the Cu translocation factor ( C/ C) compared to the control. The concentrations of PCBs and PBDEs in shoots and roots increased with increasing application rates of EDDS, and 1.58- and 1.32-fold average increases in the concentrations of PCBs and PBDEs, respectively, were observed in shoots in the EDDS treatments. A significant positive correlation was observed between shoot Cu and shoot PCBs and PBDEs. We speculate that PCBs and PBDEs were activated by the EDDS-triggered dissolved organic carbon (DOC) and then indiscriminately taken up by roots and translocated to shoots following damage to the roots mainly by the increased extractable Cu resulting from the EDDS application. [ABSTRACT FROM AUTHOR]