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The present results indicate that exogenous SA is able to improve the wheat tolerance to isoproturon toxicity.

Incorporation of organic fertilizers/amendments in soils has been, and will continue to be, a popular strategy for improving the quality of arable soils. However, the mechanism by which the dissolved organic matters (DOMs) affect soil properties or interact with other substances in soils is largely unknown. In this study, a batch equilibrium experiment was performed to evaluate the effect of two types of DOMs on the behavior of prometryne (a herbicide) in soils. Two sorts of DOMs were derived from lakebed sludge (SL) and rice straw (ST), respectively. The results show that sorption capacity in one soil for prometryne was significantly reduced by application of DOMs, whereas desorption of prometryne was promoted by DOM treatments. To understand the mobility behavior of prometryne in soils with DOMs, a column leaching experiment was carried out. It is shown that both DOMs enhanced the solubility and migration of prometryne in soils. To confirm the role of DOMs in regulating the mobility of prometryne in soils, a soil thin-layer chromatography was performed. The migration of prometryne was promoted by DOMs, which were used as a developing solvent or directly incorporated in the soil thin layer. The data indicate that DOM extracts can modify the mobility of prometryne in soil.

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Since the new tunnel is close to existing tunnel, the vibration wave induced by blasting endangers the safety and stabilization of the surrounding rock and the lining of existing tunnel. In the tunnel blasting vibration monitoring and safety prediction, Peak Particle Velocity (PPV) and vibration frequency are used widely as safety standards. To investigate the effect of blast-induced vibration from adjacent tunnel on existing tunnel, field monitoring experiments and a numerical method that is Finite Element Method (FEM) were adopted to study the blasting vibration velocity and vibration frequency of existing tunnel. Combined blasting vibration velocity with vibration frequency, the paper studied axial and radial blasting vibration velocity distributions and the corresponding Power Spectral Density (PSD) distributions of the existing tunnel under the effect of blast-induced vibration from adjacent subway tunnel. And the parameters of constitutive model and blasting loads were also discussed. It is shown that field monitoring experiment and numerical simulation can optimize blasting excavation program and provide a reference for other similar engineering projects.

The complex composition, high degree of unsaturation, and strong corrosiveness of bio-oil make direct catalytic upgrading problematic due to coking and device corrosion, and therefore, proper pretreatment is required. In this study, catalytic hydrogenation-esterification was identified as an efficient pretreatment method for bio-oil upgrading, and the hydrogenation-esterification behavior of typical compounds found in the acid-rich fraction of bio-oil over Cu/ SBA-15 catalyst was investigated. It was found that furfural, hydroxyacetone, and guaiacol could be synergistically transformed with acetic acid (AcOH) during hydrogenationesterification. Meanwhile, a higher reaction temperature promoted AcOH conversion and increased the degree of hydrogenation. On the basis of the quantification of the main products, the reaction pathways in the presence of furfural, hydroxyacetone, or guaiacol were proposed. Finally, the hydrogenation-esterification of simulated bio-oil was performed at 300 °C. The results showed that furfural, hydroxyacetone, and guaiacol were efficiently hydrogenated, and AcOH was almost completely converted into ethanol and esters, with the fraction of acid compounds drastically declining from 25.0 wt % to 0.4 wt %. Thus, a high quality pretreated bio-oil fraction, mainly consisting of alcohols and esters and ready for subsequent upgrading, was obtained in a long-term test.

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