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To promote the application of lignin in Pickering emulsions, the influences of six lignin particles with different hydrophobicity on the emulsifying and stabilizing performances for oil phases with different polarity to form oil in water Pickering emulsions were investigated. The results showed that the best emulsification performance was achieved when the three-phase (oil–water–lignin particle) contact angle was close to 90°. Alkyl-bridged lignin particles with stronger hydrophobicity have a better emulsification effect on cyclohexane with less polarity, while carboxymethylated lignin particles with stronger hydrophilicity have better emulsification effect on n-heptanol with higher polarity. Furthermore, the stability of Pickering emulsions can be improved by appropriately increasing the surface charge and decreasing the particular size of the lignin particles. [ABSTRACT FROM AUTHOR]

Improving the thermal storage stability of nanosuspension concentrate (SC) prepared from low-melting-point pesticide is a recognized problem. In this work, using pyraclostrobin as the raw material, 25 wt% of pyraclostrobin nano-SC was prepared through a water-based grinding method, and the optimal grinding conditions were obtained as follows: a grinding time of 23 h, D-3911 as dispersant and a dispersant dosage of 12 wt%. The pyraclostrobin nano-SC D90 size prepared based on this best formula was 216 nm. Adding glycerin could improve the stability of nano-SC at room temperature, but its thermal storage stability was still poor. For this problem, sodium lignosulfonate and cetyltrimethylammonium bromide (NaLS/CTAB) colloidal spheres were prepared through electrostatic and hydrophobic self-assembly and characterized. The delamination and precipitation of nano-SC can be significantly improved by adding an appropriate amount of colloidal spheres, and the nano-SC D90 size decreased from 2726 to 1023 nm after 7 days of thermal storage. Farmland experiments indicated the control efficiency of pyraclostrobin nano-SC against flowering cabbage downy mildew disease was about 30% higher than that of SC. Especially after adding the wetting agent, the effect of nano-SC could be comparable to that of commercial Kairun (currently the best pyraclostrobin formulation in the world). [ABSTRACT FROM AUTHOR]

Recently, metal–organic frameworks (MOFs) have become a promising carrier for immobilized enzymes. However, the long transmission distance and microporous nature of traditional 3D ZIF-8 materials not only reduce the accessibility of the enzyme and the substrate, but also the enzymes "encapsulated" by microporous ZIF-8 suffer compromising enzyme activity (<10% of the original enzyme activity). In this article, a method is proposed to construct one kind of new-type mesoporous 3D ZIF-8-Cu composed of 2D nanostructures that utilize a metal competitive coordination-induced defect structure by adjusting a metal guide agent copper chloride (CuCl). In addition, the feasibility of in situ encapsulating β-G within the developed mesoporous 3D ZIF-8-Cu endows that the enzyme complex (β-G@ZIF-8-Cu) possessed remarkably enhanced synergistic catalysis ability. The enzyme activity of mesoporous β-G@ZIF-8-Cu (with respect to cellobiose) was up to 50.1%, while that of 3D microporous β-G@ZIF-8 was only 5.1% at 50 °C. Significantly, with the increase of temperature, the enzyme activity of mesoporous β-G@ZIF-8-Cu increased as high as approximately 178.3%, almost 34.2 times that of β-G@ZIF-8 (5.2%) at 90 °C. This improvement results from the expansion of pores (significantly increased at 10∼50 nm), promoting substrate diffusion, and the thinner 2D structure shortened the mass transfer distance, accelerating the transport rate of reactants. In addition, 3D mesoporous β-G@ZIF-8-Cu composed of multilayer 2D nanostructures with better high-temperature resistance. [ABSTRACT FROM AUTHOR]