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Quantitative analysis of harmful patina components on the surface of bronzeware is crucial as patina can corrode artifacts. Surface-enhanced Raman spectroscopy (SERS) has a common application in surface analysis. However, there exists an absence of documented investigations concerning the quantitative analysis of detrimental patina, particularly the chloride patina. To achieve high sensitivity in targeting harmful patina, we report a fabrication method for constructing Ag/Au alloys in the pores and on the surface of UiO-66 (zirconium 1,4-dicarboxybenzene metal–organic framework) nanomaterials, resulting in Ag/Au/UiO-66 nanoparticle monolayers formed by self-assembly at the oil–water interface. By incorporating them onto the surface of PVA hydrogel, we obtained SERS sensor devices with excellent flexibility, outstanding optical transparency, and ultrahigh activity. These sensor devices efficiently sample irregular surfaces and detect micrometer-scale specimen. They significantly enhance the Raman characteristic peaks of measured objects, facilitating precise analysis of the patina composition on the surface of bronze artifacts. The Raman peak at 118 cm–1 was boosted from 367 to 11,909 for detecting harmful patina, and the enhancement factor of the SERS substrate was calculated to be 3.6 ×1010 for detecting the Raman peak of rhodamine 6G (R6G), which could be easily detected at 610 cm–1 at a concentration of 10–13 mol/L (M). The Raman peaks at 610 cm–1 from the SERS substrate could also be readily detected. By grafting the organic fluorescent group amino-MQAE onto the surface of Ag/Au/UiO-66 nanoparticles (NPs), the content of harmful patina on the surface of bronze artifacts treated for different durations was indirectly determined. These results indicate the successful construction of the Ag/Au alloy on the surface of UiO-66 NPs, resulting in SERS sensor devices with excellent flexibility, optical transparency, and ultrahigh sensitivity. [ABSTRACT FROM AUTHOR]

A pivotal challenge in metabolite research is the structural annotation of metabolites from tandem mass spectrometry (MS/MS) data. The integration of artificial intelligence (AI) has revolutionized the interpretation of MS data, facilitating the identification of elusive metabolites within the metabolomics landscape. Innovative methodologies are primarily focusing on transforming MS/MS spectra or molecular structures into a unified modality to enable similarity-based comparison and interpretation. In this work, we present CMSSP, a novel Contrastive Mass Spectra-Structure Pretraining framework designed for metabolite annotation. The primary objective of CMSSP is to establish a representation space that facilitates a direct comparison between MS/MS spectra and molecular structures, transcending the limitations of distinct modalities. The evaluation on two benchmark test sets demonstrates the efficacy of the approach. CMSSP achieved a remarkable enhancement in annotation accuracy, outperforming the state-of-the-art methods by a significant margin. Specifically, it improved the top-1 accuracy by 30% on the CASMI 2017 data set and realized a 16% increase in top-10 accuracy on an independent test set. Moreover, the model displayed superior identification accuracy across all seven chemical categories, showcasing its robustness and versatility. Finally, the MS/MS data of 30 metabolites from Glycyrrhiza glabra were analyzed, achieving top-1 and top-3 accuracies of 86.7 and 100%, respectively. The CMSSP model serves as a potent tool for the dissection and interpretation of intricate MS/MS data, propelling the field toward more accurate and efficient metabolite annotation. This not only augments the analytical capabilities of metabolomics but also paves the way for future discoveries in understanding of complex biological systems.

Nonradical oxidation has been determined to be a promising pathway for the degradation of organic pollutants in heterogeneous catalytic ozonation (HCO). However, the bottlenecks are the rational design of catalysts to selectively induce nonradicals and the interpretation of detailed nonradical generation mechanisms. Herein, we propose a new HCO process based on single-atom iron catalysts, in which Fe-N 4 sites anchored on the carbon skeleton exhibited outstanding catalytic ozonation activity and stability for the degradation of oxalic acid (OA) and p -hydroxybenzoic acid (pHBA) as well as the advanced treatment of a landfill leachate secondary effluent. Unlike traditional radical oxidation, nonradical pathways based on surface-adsorbed atomic oxygen (*O ad ) and singlet oxygen ( 1 O 2 ) were identified. A substrate-dependent behavior was also observed. OA was adsorbed on the catalyst surface and mainly degraded by *O ad , while pHBA was mostly removed by O 3 and 1 O 2 in the bulk solution. Density functional theory calculations and molecular dynamics simulations revealed that one terminal oxygen atom of ozone preferred bonding with the central iron atom of Fe-N 4 , subsequently inducing the cleavage of the O-O bond near the catalyst surface to produce *O ad and 1 O 2 . These findings highlight the structural design of an ozone catalyst and an atomic-level understanding of the nonradical HCO process.

A nickel-catalyzed reductive cross-coupling has been achieved using (hetero)aryl bromides and vinyl acetate as the coupling partners. This mild, applicable method provides a reliable access to a variety of vinyl arenes, heteroarenes, and benzoheterocycles, which should expand the chemical space of precursors to fine chemicals and polymers. Importantly, a sustainable solvent, dimethyl isosorbide, is used, making this protocol more attractive from the point of view of green chemistry.

Heterogeneous catalytic ozonation is regarded as a feasible technology in advanced wastewater treatment. Catalytic performance, mass transfer, and mechanical strength are the key elements for large-scale applications of catalysts. To optimize those elements, Fe was selected for its dual role in graphitization and catalytic ozonation. A Fe/N-doped micron-scale carbon-Al 2 O 3 framework (CAF) was designed and applied to a fluidized catalytic process for the treatment of secondary effluent from coal gasification. The chemical oxygen demand removal rate constant and the hydroxyl radical generation efficiency ( R ct ) of the Fe/N-doped CAF were 190% and 429% higher than those of pure ozone, respectively. Theoretical calculations revealed that higher Fe valence promoted ozone decomposition, which implied increasing Fe III content for further catalyst optimization. The rate constant and R ct with a higher Fe III -proportion catalyst were increased by 13% and 16%, respectively, compared to those with the lower one. Molecular dynamics and density functional theory calculations were performed to analyze the reaction kinetics qualitatively and quantitatively. The energy barrier corresponding to Fe III configuration was 1.32 kcal mol -1 , 27% lower than that for Fe II configuration. These theoretical calculations guided the catalyst optimization and provided a novel solution for designing ozonation catalysts. The Fe/N-doped CAF demonstrated a great potential for practical applications.

The monocot lineage-specific miR528 was previously established as a multistress regulator. However, it remains largely unclear how miR528 participates in response to salinity stress in rice. Here, we show that miR528 positively regulates rice salt tolerance by down-regulating a gene encoding l-ascorbate oxidase (AO), thereby bolstering up the AO -mediated abscisic acid (ABA) synthesis and ROS scavenging. Overexpression of miR528 caused a substantial increase in ascorbic acid (AsA) and ABA contents but a significant reduction in ROS accumulation, resulting in the enhanced salt tolerance of rice plants. Conversely, knockdown of miR528 or overexpression of AO stimulated the expression of the AO gene, hence lowering the level of AsA, a critical antioxidant that promotes the ABA content but reduces the ROS level, and then compromising rice tolerance to salinity. Together, the findings reveal a novel mechanism of the miR528- AO module-mediated salt tolerance by modulating the processes of AsA and ABA metabolism as well as ROS detoxification, which adds a new regulatory role to the miR528- AO stress defense pathway in rice.

Protonolysis of β-diketiminato (nacnac) rare-earth metal bis-alkyl complexes L nacnac LnR 2 (THF) (Ln = Y and Lu) with 2 equiv of Ph 2 PNHPh or Ph 2 PCH 2 NHPh afforded the bis-amido complexes L nacnac Y(Ph 2 PNPh) 2 and L nacnac Ln(Ph 2 PCH 2 NPh) 2 (Ln = Y and Lu). Metalation of the latter complexes with 1 equiv of Ni(COD) 2 led to the isolation of unusual heterobimetallic Ni(II)-Ln(III) complexes formed via P-C bond cleavage of one [Ph 2 PCH 2 NPh] - ligand. Notably, both the imine PhN═CH 2 and phosphide Ph 2 P - fragments from the P-C bond cleavage were trapped in the Ni(II)-Ln(III) core with a relatively weak interaction between the two metal centers. The Ni(II)-Y(III) complex have exhibited versatile reactivity, such as coordination of isonitrile to the Ni(II) center, insertion of nitrile with the coordinated imine, and ring-opening of the epoxide by nucleophilic attack from the phosphide group.

Conventional dense thin-film composite (TFC) membranes evince a universally low water permeability, the increase of which typically relies on introducing additional transport channels based on intricate steps within a membrane preparation process. In this study, we reported a novel and simplified procedure for the fabrication of high-performance TFC membranes. Specifically, the dissolution of aqueous monomers in the casting solution was utilized for the following interfacial polymerization (IP). Since the monomers diffused to the water bath during phase inversion, the control of precipitation time enabled an effective regulation of the monomer concentration in the formed polymeric substrates, where the IP reaction was initiated by the addition of the organic phase. The entire and uniform embedment of aqueous monomers inside the substrates contributed to the formation of ultrathin and smooth selective layers. An excellent separation performance (i.e., water permeability: 34.7 L m -2 h -1 bar -1 ; Na 2 SO 4 rejection: ∼96%) could be attained using two types of aqueous monomers (i.e., piperazine and β-cyclodextrin), demonstrating the effectiveness and universality of this method. Compared to the conventional immersion-based process, this novel procedure shows distinct advantages in reducing monomer usage, shortening the production cycle, and achieving a more superior membrane performance, which is highly promising for large-scale membrane manufacture.

Flow-electrode electrochemical desalination (FEED) processes (e.g., flow-electrode capacitive deionization), which use flowable carbon particles as the electrodes, have attracted increasing attention, holding the promise for continuous desalination and high desalting efficiency. While it is generally believed that carbon particles with abundant microporous and large specific capacitances (e.g., activated carbon, AC) should be ideal candidates for FEED electrodes, we provide evidence to the contrary, showing that highly conductive electrodes with low specific surface area can outperform microporous AC-based electrodes. This study revealed that FEED using solely high surface area AC particles (∼2000 m 2 g -1 , specific capacitance of ∼44 F g -1 , average salt adsorption rate of ∼0.15 μmol cm -2 min -1 ) was vastly outperformed by electrodes based solely on low-surface area carbon black (CB, ∼70 m 2 g -1 , ∼0.5 F g -1 , ∼0.75 μmol cm -2 min -1 ). Electrochemical impedance spectroscopy results suggest that the electrode formed by CB particles led to more effective electronic charge percolation, likely contributing to the improved desalination performance. In addition, we propose and demonstrate a novel operation mode, termed single cycle (SC), which greatly simplified the FEED cell configuration and enabled simultaneous charging and discharging. Using SC mode with CB flow electrodes delivered an increased average salt removal rate relative to the more traditional short-circuited closed cycle (SCC) mode, achieving up to 1.13 μmol cm -2 min -1 . Further investigations demonstrate that up to 50% of energy input would be avoided when using CB flow electrodes operated under SC mode as compared to that of AC flow electrodes operated under SCC mode. In summary, the FEED process presented in this study provided an innovative and promising approach toward high-efficient and low-cost brackish water desalination.

Objects can radiate emission of heat to outer empty space (3 K) through an atmospheric window (8-13 μm), resulting in a possibility for radiative cooling. Multilayer film stacking designs and complex nanophoton coolers have been reported for radiative cooling. Here, we have found that single nanoporous MgHPO 4 ·1.2H 2 O powder has a high reflectance of 92.20% in the solar spectral region of 0.3-2.5 μm and a high emissivity of 0.94 in the atmospheric window of 8-13 μm. The powder was film-coated on ceramic tiles for temperature and cooling power tests on Al foil. The test results showed that the MgHPO 4 ·1.2H 2 O coating on the ceramic tile could achieves a daytime radiative cooling of 4.1 °C below the ambient air temperature and a nighttime radiative cooling of 7.6 °C. The average cooling power reaches 78.18 W/m 2 . Such a simple and low-cost single nanoporous MgHPO 4 ·1.2H 2 O powder material offers a novel option for large-scale applications of radiative cooling.

While the contact angle is a well-applied indicator of membrane hydrophobicity and surface energy, the interference of surface roughness and porosity in contact angle measurement and surface energy calculation has been long neglected in the field of porous membrane study. We propose an improved method to straightforwardly derive the surface energy of the porous membrane from contact angles with the interference effect corrected. A linearized model was established combining the Young-Dupré and Cassie-Baxter equations, from which the surface energy (Lifshitz-van der Waals and Lewis acid/base components) and roughness index (surface area difference) can be solved simultaneously at a given porosity using contact angles measured with a set of standard polar/nonpolar test liquids. The model solution was examined using hydrophilic microfiltration membranes with different pore morphologies (including perforated plate-like PCTE, irregular particulate bed-like PVDF, and fibrous mesh-like PTFE membranes), with the robustness of the results evaluated via Monte Carlo simulation. In comparison with the verified results of the model solution, it was found that the Lifshitz-van der Waals Lewis acid/base energy values for the tested membranes would deviate by 50-87, 30-160, and 52-97%, respectively, if surface roughness and porosity were neglected in the calculation. The profound effect of roughness and porosity on surface energy determination was further confirmed via theoretical analysis of the Young-Dupré and Cassie-Baxter relationships. This improved approach may apply to the surface energy characterization of hydrophilic rough porous membranes (e.g., hydrophilic microfiltration membranes).

During catalytic ozonation, Al 2 O 3 -supported catalysts usually have stable structures but relatively low surface activity, while carbon-supported catalysts are opposite. To encourage their synergisms, we designed a Ni-induced C-Al 2 O 3 -framework ( Ni CAF) and reinforced it with a Cu-Co bimetal to create an efficient catalyst (CuCo/ Ni CAF) with a core-multishell structure. The partial graphitization of carbon adjacent to Ni crystals formed a strong out-shell on the catalyst surface. The rate constant for total organic carbon removal of CuCo/ Ni CAF (0.172 ± 0.018 min -1 ) was 67% and 310% higher than that of Al 2 O 3 -supported catalysts and Al 2 O 3 alone, respectively. The metals on CuCo/ Ni CAF contributed to surface-mediated reactions during catalytic ozonation, while the embedded carbon enhanced reactions within the solid-liquid boundary layer and in the bulk solution. Moreover, carbon embedment provided a 76% increase in ·OH-production efficiency and an 86% increase in organic-adsorption capacity compared to Al 2 O 3 -supported catalysts. During the long-term treatment of coal-gasification wastewater (∼5 m 3 day -1 ), the pilot-scale demonstration of CuCo/ Ni CAF-catalyzed ozonation revealed a 120% increase in ozone-utilization efficiency (ΔCOD/ΔO 3 = 2.12) compared to that of pure ozonation (0.96). These findings highlight catalysts supported on Ni CAF as a facile and efficient approach to achieve both high catalytic activity and excellent structural stability, demonstrating that they are highly viable for practical applications.

Gene transfer in biofilms is known to play an important role in antibiotic resistance dissemination. However, the process remains poorly understood. In this study, microfluidics with time-lapse imaging was used for real-time monitoring of plasmid-mediated horizontal gene transfer (HGT) in biofilms. Pseudomonas putida KT2440 harboring an antibiotic resistance plasmid RP4 was chosen as the donor while Escherichia coli and activated sludge bacteria were used as the recipient cells. Dynamic features of the transfer process, including the transfer rate, cell growth rate and kinetic changes of the transfer frequency, were determined. It was found that the routes for gene transfer strongly depend on the structure and composition of a biofilm. While intraspecies HGT is essential to initiate a transfer event, the secondary retransfer from transconjugants to the same species is more efficient and can cause cascading gene spread in single-strain biofilms. For the activated sludge biofilm, only small and scattered colonies formed and vertical gene transfer appears to be the dominant route after initial intraspecies transfer. Furthermore, more than 46% of genera in the activated sludge were permissive to plasmid RP4, many of which are associated with human pathogens. These phenomena imply early prevention and interruptions to biofilm structure could provide an effect way to inhibit rapid antibiotic resistance gene spread and reduce the likelihood of catastrophic events associated with antibiotic resistance.

Phosphonamidate 3a of methoxymethylphosphonic acid (MMPA) with propofol (1) and l-alanine ethyl ester was found to be an efficient scaffold for the oral delivery of compound 1. The synthesis and evaluation of MMPA based phosphonamidates of compound 1, HSK3486 (2), and other phenolic drugs revealed the general application of MMPA as the effective delivery vehicle for phenolic drugs. On the basis of plasma concentrations of compound 1 and SN38 (14), the oral bioavailability of compound 3a and 15 in beagle dogs was found to be 97.6% and 34.1%, respectively.