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Membrane distillation (MD) has great potential in the management of hypersaline water for zero liquid discharge (ZLD) due to its high salinity tolerance. However, the membrane wetting issue significantly restricts its practical application. In this study, a composite membrane tailored for extreme concentrations and even crystallization of hypersaline water is synthesized by coating a commercial hydrophobic porous membrane with a composite film containing a dense polyamide layer, a cation exchange layer (CEL), and an anion exchange layer (AEL). When used in direct contact MD for treating a 100 g L -1 NaCl hypersaline solution, the membrane achieves supersaturation of feed solution and a salt crystal yield of 38.0%, with the permeate concentration at <5 mg L -1 . The composite membrane also demonstrates ultrahigh antiwetting stability in 360 h of long-term operation. Moreover, ion diffusion analysis reveals that the ultrahigh wetting resistance of the composite membrane is attributed to the bipolar AEL and CEL that eliminate ion crossover. The literature review elucidates that the composite membrane is superior to state-of-the-art membranes. This study demonstrates the great potential of the composite membrane for direct crystallization of hypersaline water, offering a promising approach to filling the gap between reverse osmosis and conventional thermal desalination processes for ZLD application.

The impact of Sn on the concentration and strength of acid sites in Al containing zeolites with MFI topology and their catalytic activity for the dehydration of cyclohexanol in the aqueous phase has been investigated. The materials maintain constant Al concentrations and consequently Bro̷nsted acid site (BAS) concentrations, while exhibiting an increasing concentration of Sn Lewis acid sites (LAS). The presence of water alters LAS (Sn) , leading to weak BAS (Sn) that increases the concentration of water in the zeolite micropore, while leaving the rate of dehydration of cyclohexanol unchanged. The TOF increases with the concentration of BAS (Al) in close contact with framework LAS (Sn) , referred to as BAS (Pair) . The increase in the Arrhenius pre-exponential factor, without affecting the activation barrier ( E a ), leads to the hypothesis that the proximity of both sites allows for a later transition state induced by the polarization of the C-O bond, leading in turn to a higher transition entropy., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

Validamycin A (VMA) is an antifungal antibiotic derived from Streptomyces hygroscopicus commonly used in plant disease management. Surprisingly, VMA was discovered to impede the production of fumonisin B1 (FB 1 ) in agricultural settings. However, the specific target of VMA in Fusarium verticillioides remained unclear. To unravel the molecular mechanism of VMA, ultrastructural observations unveiled damage to mitochondrial membranes. Trehalase (FvNth) was pinpointed as the target of VMA by utilizing a 3D-printed surface plasmon resonance sensor. Molecular docking identified Trp 285 , Arg 447 , Asp 452 , and Phe 665 as the binding sites between VMA and FvNth. A ΔFvnth mutant lacking amino acids 250-670 was engineered through homologous recombination. Transcriptome analysis indicated that samples treated with VMA and ΔFvnth displayed similar expression patterns, particularly in the suppression of the FUM gene cluster. VMA treatment resulted in reduced trehalase and ATPase activity as well as diminished production of glucose, pyruvic acid, and acetyl-CoA. Conversely, these effects were absent in samples treated with ΔFvnth . This research proposes that VMA hinders acetyl-CoA synthesis by trehalase, thereby suppressing the FB 1 biosynthesis. These findings present a novel target for the development of mycotoxin control agents.

In situ Al K-edge X-ray absorption near edge structure (XANES) and Extended X-ray absorption fine structure (EXAFS) spectroscopy in conjunction with ab initio molecular dynamics (AIMD) simulations show that adsorption of 1-propanol alters the structure of the Brønsted acid site through changes in the associated aluminum-oxygen tetrahedron in zeolite H-MFI. The decreasing intensity of the pre-edge signal of the in situ Al K-edge XANES spectra with increasing 1-propanol coverage shows that Al T-sites become more symmetric as the sorbed alcohol molecules form monomers, dimers, and trimers. The adsorption of monomeric 1-propanol on Brønsted acid sites reduces the distortion of the associated Al T-site, shortens the Al-O distance, and causes the formation of a Zundel-like structure. With dimeric and trimeric alcohol clusters, the zeolite proton is fully transferred to the alcohols and the aluminum-oxygen tetrahedron becomes fully symmetric. The subtle changes in Al-K-edge XANES in the presence of sorbate structures, with the use of theory, are used to probe the local zeolite structures and provide a basis to predict the population and chemical state of the sorbed species., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

Trichlorfon (TCF) is an important organophosphate pesticide in agriculture. However, limited information is known about the biodegradation behaviors and kinetics of this pesticide. In this study, a newly isolated fungus (PA F-2) from pesticide-polluted soils was identified as Aspergillus sydowii on the basis of the sequencing of internal transcribed spacer rDNA. This fungus degraded TCF as sole carbon, sole phosphorus, and sole carbon-phosphorus sources in a mineral salt medium (MSM). Optimal TCF degradation conditions were determined through response surface methodology, and results also revealed that 75.31% of 100 mg/L TCF was metabolized within 7 days. The degradation of TCF was accelerated, and the mycelial dry weight of PA F-2 was remarkably increased in MSM supplemented with exogenous sucrose and yeast extract. Five TCF metabolic products were identified through gas chromatography-mass spectrometry. TCF could be initially hydrolyzed to dichlorvos and then be degraded through the cleavage of the P-C bond to produce dimethyl hydrogen phosphate and chloral hydrate. These two compounds were subsequently deoxidized to produce dimethyl phosphite and trichloroethanal. These results demonstrate the biodegradation pathways of TCF and promote the potential use of PA F-2 to bioremediate TCF-contaminated environments.