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Humic acid (HA) has attracted increasing attention as a new type of organic fertilizer in horticultural production, such as greenhouse-planted cherry tomato. However, we need more information to evaluate the effects of HA on soil rhizosphere bacteria and tomato performance under greenhouse conditions. In this study, greenhouse-planted cherry tomato was observed with HA added at dosages of 1500, 3000, 4500, and 6000 kg·ha -1 , respectively. The other two organic fertilizers [farmyard manure (FM) and commercial organic fertilizer (COF)], were used as comparison with a dosage of 3000 kg·ha -1 . Illumina MiSeq sequencing was conducted for bacterial diversity analysis, and tomato quality analysis based on total soluble solids, titratable acid, and sugar-acid ratio was performed for different fertilizer treatments. The results revealed that HA application resulted in the best flavor, compared to CK without the organic fertilizer used and with the other two organic fertilizers. The Chaol estimator and Shannon index showed that fertilizer addition decreased microbial diversity but increased species richness. At a dosage of 3000 kg·ha -1 , the effects of different fertilizers were ranked as HA > FM > COF. Our findings offered suggestions to reasonably optimize cherry tomato organic fertilizer application., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Two-dimensional (2D) materials have been developed into various catalysts with high performance, but employing them for developing highly stable and active nonprecious hydrogen evolution reaction (HER) catalysts still encounters many challenges. To this end, the machine learning (ML) screening of HER catalysts is accelerated by using genetic programming (GP) of symbolic transformers for various typical 2D MA 2 Z 4 materials. The values of the Gibbs free energy of hydrogen adsorption (Δ G H* ) are accurately and rapidly predicted via extreme gradient boosting regression by using only simple GP-processed elemental features, with a low predictive root-mean-square error of 0.14 eV. With the analysis of ML and density functional theory (DFT) methods, it is found that various electronic structural properties of metal atoms and the p-band center of surface atoms play a crucial role in regulating the HER performance. Based on these findings, NbSi 2 N 4 and VSi 2 N 4 are discovered to be active catalysts with thermodynamical and dynamical stability as Δ G H* approaches to zero (-0.041 and 0.024 eV). In addition, DFT calculations reveal that these catalysts also exhibit good deuterium evolution reaction (DER) performance. Overall, a multistep workflow is developed through ML models combined with DFT calculations for efficiently screening the potential HER and DER catalysts from 2D materials with the same crystal prototype, which is believed to have significant contribution to catalyst design and fabrication.

The density and volumetric behavior of three typical n -alkanes (hexane, octane, and decane) influenced by different mole fractions of CO 2 injected in them at temperatures from 303 to 363 K and pressures from 3.8 to 8.67 MPa were investigated by performing molecular dynamics simulations. It is shown that the mass density first increases and then decreases with increasing CO 2 mole fraction. Correspondingly, the system volume only slightly swells at low CO 2 contents while suddenly expanding when the CO 2 mole fraction exceeds a value of ∼60%. The calculations of structural properties and interaction energies indicate that at low CO 2 mole fractions, there are a few CO 2 molecules existing in the gap of alkane molecules, resulting in poor compressibility, while at higher CO 2 concentrations, the CO 2 molecules begin to separate from the CO 2 -saturated alkane phase and form a gas phase, leading to higher compressibility. Therefore, at high CO 2 mole fractions, the system density and volume can more easily be changed by temperature and pressure than that at low CO 2 mole fractions. In addition, since it is harder for alkanes with longer chains to separate from each other, the volume swelling decreases and the density increases with increasing carbon number of n -alkane chains. Finally, we found that the increase in CO 2 mole fraction, temperature, and the decrease in alkane chain length would promote the diffusion of both CO 2 and alkane molecules. However, the influence of pressure on molecular diffusion is very limited except when P = 8.67 MPa and T = 333 K, where CO 2 is in the supercritical state. This work is helpful for understanding the density and volumetric behavior of n -alkane/CO 2 mixtures at a molecular level and provides useful information for guiding carbon sequestration and CO 2 -enhanced oil recovery., Competing Interests: The authors declare no competing financial interest., (© 2021 The Authors. Published by American Chemical Society.)

Although biochar is a promising soil enhancement material, we have limited understanding of its effect on certain pesticide in soils and plants under field conditions. The aim of this study was to examine the impact of walnut shell biochar (WSB), which is rich in benzylic ring C and lignin charcoal, on the degradation dynamics of chlorantraniliprole (CAP) and acetochlor in Brassica chinensis L. fields. The functional group structure, aromatic ring structure, and crystallite size of the WSB were determined by thermogravimetric analysis and derivative thermogravimetry analysis (TGA-DTG), NMR, Raman spectroscopy, and X-ray diffraction, respectively. With WSB applications of 5% (v/v) in root soil, B. chinensis L. growth was facilitated. Degradation dynamic analysis showed that the half-life of CAP on B. chinensis L. and in soil did not change greatly. For acetochlor, the half-life in soil was 6.93 days with WSB application and 9.90 days without WSB application. The WSB application increased bioconcentration factor values more significantly for acetochlor than for CAP. These results show that WSB has a greater impact on acetochlor than on CAP when used for pesticide degradation in the field., Competing Interests: The authors declare no competing financial interest., (© 2020 American Chemical Society.)

Pyrolysis is a highly promising technology for the efficient utilization of low-rank coal. The structure of coal plays an important role in its utilization. In this paper, the evolution of the char structure during heat treatment (200-800 °C) of Naomaohu coal and its different vitrinite-rich fractions was studied. The functional group structure, aromatic ring structure, and crystallite size of chars were determined by Fourier transform infrared (FTIR) spectroscopy, Raman spectroscopy, and X-ray diffraction (XRD) spectroscopy, respectively. The results indicated that minerals inhibit the condensation reaction of aromatic rings during pyrolysis. The high vitrinite content in coal is conducive to the formation of larger char crystallite average sizes ( L a ). The relationship between L a (1.69-3.10 nm) and the Raman band area ratio A (G R +V L +V R ) / A D or A D / A all was established. In addition, the combustion performance and kinetics of chars were also investigated. The results showed that the char from high contents of the liptinite fraction has lower combustion reactivity, and demineralization treatment has significantly reduced the combustion reactivity of char., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)

Supercritical water oxidation of chlorobenzene (CB) was studied using an anticorrosive fused-silica capillary reactor (FSCR) combined with a polarization microscope recorder system for visual observations and a Raman spectroscopic system for qualitative and quantitative analyses of the gaseous products. The effects of operating parameters, including the stoichiometric amount of oxidizer, temperature, and reaction time, on oxidation behavior were investigated. Our results show that a 100% conversion yield of CB and 100% CO(2) yield were achieved with a 150% stoichiometric amount of H(2)O(2) at 450 °C within 8 and 10 min, respectively. The conversion yield and the CO(2) yield both depend strongly on temperature, and the CO(2) yield is always less than the CB conversion yield under the same experimental conditions, suggesting that some carbon exists in intermediate products of incomplete oxidation, as confirmed by gas chromatography-mass spectrometry. Global kinetics analysis based on the complete conversion of CB to CO(2) showed that the reaction was first order. CB phase-changes in sub- and supercritical H(2)O-H(2)O(2) system in the FSCR were observed and recorded; CB eventually dissolved completely to form a homogeneous liquid solution above 326.1 °C. This method has great potential for use in the theoretical study of fluids and chemical reactions under elevated pressure-temperature conditions.

Despite the fact that the biological processes of chiral compounds are enantioselective, the endocrine disruption activity and uptake of chiral contaminants with respect to enantioselectivity has so far received limited research. In this study, the estrogenic potential and uptake of the enantiomers of a newer pyrethroid insecticide, bifenthrin (BF), were investigated. Significant differences in estrogenic potential were observed between the two enantiomers in the in vitro human breast carcinoma MCF-7 cell proliferation assay (i.e., the E-SCREEN assay) and the in vivo aquatic vertebrate vitellogenin enzyme-linked immunosorbent assay (ELISA). In the E-SCREEN assay, the relative proliferative effect ratios of 1S-cis-BF and 1R-cis-BF were 74.2% and 20.9%, respectively, and the relative proliferative potency ratios were 10% and 1%, respectively. The cell proliferation induced by the two BF enantiomers may be through the classical estrogen response pathway via the estrogen receptor (ER), as the proliferation induced by the enantiomers could be completely blocked when combined with 10-6 mol/L of the ER antagonist ICI 182,780. Measurement of vitellogenin induction in Japanese medaka (Oryzias latipes) showed that, at an exposure level of 10 ng/mL, the response to 1S-cis-BF was about 123 times greater than thattothe Renantiomer. Significant selectivity also occurred in the uptake of BF enantiomers in the liver and other tissues of J. medaka. These results together suggest that assessment of the environmental safety of chiral insecticides should consider enantioselectivity in acute and chronic ecotoxicities such as endocrine disruption.