JOURNAL OF COLLOID AND INTERFACE SCIENCE
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2024
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IF 9.4
Yan Chen,Guojun Lv,Xuyang Zou,Shihao Su,Jiangzhang Wang,Chaoyi Zhou,Jialing Shen,Yangbin Shen,Zhongmin Liu
Dealuminated Beta zeolite has a large amount of silanol defects on its interface, which provides an ideal place for embedding metal species and creating metal active sites in a confined microenvironment. The confined metal sites as well as their surroundings are closely related to the reactant activation and transient state achievement. Hence, unraveling the confined metal sites is of great significance for the catalytic reaction process. Herein, niobium species were incorporated into the silanol defects over dealuminated Beta zeolite with a facile dry impregnation method, co-grinding the niobium precursor with dealuminated Beta zeolite support. The successful incorporation of niobium into the silanol defects for 30Nb-Beta zeolite was verified by DRIFT, 1 H MAS NMR, UV–Vis and UV-Raman characterizations. XAS characterization and DFT calculations further disclosed that the confined Nb species existed as (SiO) 2 Nb(OH)(=O), containing two Si−O−Nb bonds, one Nb=O bond as well as one Nb−OH bond. The synthesized 30Nb-Beta zeolite catalyst displayed a superior cyclohexene conversion of 51.1%, cyclohexene oxide selectivity of 83.1% as well as TOF value of 188.2 h −1 ascribed to the inherent electrophilicity of Nb(V) for confined (SiO) 2 Nb(OH)(=O) species as well as the low oxygen transfer energy barrier for Nb V −OOH species. Furthermore, the prepared 30Nb-Beta zeolite can be effectively employed to other cyclic alkene epoxidation reactions.
研究领域:
催化化学
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材料科学
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DOI
PubMed
高影响因子
Catalysis Science & Technology
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2021
·Vol. 11
·期 19
·6498-6506
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IF 6.119
Shengxin Chen,Ran An,Yingwei Li,Yuting Zhu,XinBao Zhu,Ruixia Liu,Xingang Li
Although poly(ionic liquid)s (PILs) have received extensive attention and research, the strategy for designing efficient PILs catalysts remains a challenge. This work reports a series of efficient PILs catalysts with increasing ionic ratio and various anion species to regulate electrophilic/nucleophilic ability, and explores the effect of the ionic ratio on the coupling reaction of propylene oxide (PO) with CO2 or methanol. These PILs are synthesized by a quaternization reaction between poly(N-vinylimidazole) (PVIM) and dihaloalkanes, where the amount of crosslinker of dihaloalkanes controls the ionic ratio of PILs, further affecting their microcosmic environment, morphologies and properties. It is noteworthy that the ionic ratio with IL units and imidazoline group can work as a trigger and promoter in the coupling reaction of PO with CO2 or methanol. The ionic ratio could open the reaction compared with the parent PVIM and the choice of anion could turn the reaction on or off. It suggested that the active microstructure and electrophilic/nucleophilic ability of PILs could be regulated by the ionic ratio. In these active sites, the IL units-connected imidazoline group could weaken the interaction of the cation–anion, giving enhanced leaving ability of the anion, contributing to the excellent catalytic performance.
研究领域:
催化化学
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材料科学
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环境化学
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高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Hao Chen,Xiaofeng Xie,Chaofang Li,Xudong Liu,Fenghua Shen,Pingshan Wang,Kaisong Xiang,Hui Liu
Ionic liquids (ILs) show promise for flue gas purification, but suffer from the insufficient oxidation ability for elemental mercury (Hg 0 ) removal. In light of the critical role of electrophilic structure in the oxidation process, we proposed a novel strategy to enhance Hg 0 oxidative capture by steering electrophilicity of positively charged N center in the cation of IL. We screened ILs containing cations with N centers featuring varied hybridization and localization, and thioacetate anions that aid in immobilizing the resulting mercury ions. The electrophilicity of ILs, as determined by quantum chemical calculations, adheres to the following hierarchy: [Bpy][ThAc] (highly delocalized sp 2 -hybridized N) > [Bmim][ThAc] (low delocalized sp 2 -hybridized N) > [Bpyrr][ThAc] (sp 3 -hybridized N) ≈ [Bpip][ThAc] (sp 3 -hybridized N). This hierarchy correlated positively with experimental oxidation activity and Hg 0 removal performance. Specifically, the Hg 0 adsorption capacity of [Bpy][ThAc] (23.0 mg/g) was 3.6 times larger than that of [Bmim][ThAc]. Hg-TPD, XPS, and theoretical calculations corroborated that the highly delocalized sp 2 -hybridized N with a stable π system in [Bpy][ThAc] constitutes a strong electrophilic center, boosting electron transfer from Hg 0 to the cation. Subsequently, the oxidized Hg 2+ was immobilized through coordination with the anion. Furthermore, beyond the specific mercury removal process, the integration of Hg 0 capture with desulfurization was successfully achieved by introducing [Bpy][ThAc] into the IL employed for desulfurization, highlighting its adaptability and practicability. This work not only develops an effective remediator for Hg 0 removal from the flue gas but also offers design guidelines for ILs used in the oxidative degradation of other contaminants.
研究领域:
环境科学
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化学工程
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DOI
高影响因子
WATER RESEARCH
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2025
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IF 12.4
Xiaoming Zou,Baoyin Zhang,Yujiao Jing,Lihui Zong,Ligui Wu,Qunyan Zhou,Yue Fang,Kaifang Shen,Xubiao Luo,Lingling Rong
The pivotal role of plasmid-mediated conjugative transfer in the spread of antibiotic resistance genes (ARGs) is well established, and environmental chemicals exert considerable selective pressure on this process. Oral antidiabetic drugs (OADs) are frequently detected in aquatic environments at concentrations reaching the mg/L range. However, their influence on the conjugative transfer of plasmid remains largely unexplored. Here, we investigated the effects of eight widely used OADs on the transfer of the RP4 plasmid between Escherichia coli strains isolated from representative wastewater sources. The results showed that all tested OADs significantly enhance plasmid transfer ( P < 0.05), albeit with up to a four - fold variation in change. Notably, this phenomenon is independent of OAD degradation profiles, but strongly associated with bacterial biochemical responses ( P < 0.05) such as reactive oxygen species (ROS) production, cell membrane permeability, and ATP synthesis. Mechanistic analyses further identify OAD electrophilicity as a key chemical determinant, modulating both physiological processes (membrane permeability and ATP production) and molecular components—genes ( ybbA, mlaA , and ompF ) and their corresponding proteins (YbbA, MlaA, and OmpF)—involved in conjugative transfer. Furthermore, results demonstrate that OADs consistently increase ARG abundance and diversity in activated sludge systems, an effect strongly correlated with their electrophilicity ( P < 0.05). Collectively, our findings reveal, for the first time, that OAD electrophilicity is a critical driver of ARG dissemination in wastewater treatment systems, thereby providing molecular-level insights and a theoretical foundation for controlling ARG spread.
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高影响因子
Environmental Science-Nano
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2020
·Vol. 7
·期 7
·1899-1911
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IF 7.683
Chunyang Nie,Zhenhua Dai,Wenjie Liu,Xiaoguang Duan,Chengyin Wang,Bo Lai,Zhimin Ao,Shaobin Wang,Taicheng An
Carbon-catalyzed persulfate activation is a metal-free advanced oxidation process for abating aqueous organic micropollutants. Recently, the electron-transfer mechanism in the activation of peroxydisulfate (PDS) has attracted tremendous interest due to its unknown nonradical reaction pathways. The conventionally used atomic-scale descriptors of adsorption energy (Eads), O–O bond length (lO–O) and S–O bond length (lS–O) cannot accurately reflect the ability of the functionalities of PDS in its activation. In this work, a new descriptor, local electrophilicity index (ω), which represents the oxidative capacity of adsorbed S2O82−, was included to identify the intrinsic active sites in carbocatalysts via density functional theory calculations. To verify the reliability of the proposed criteria, the catalytic performances of a series of highly boronated and nitrogenated carbon nanotube/nanosheet composites (BCN-NT/NS) with tailored physicochemical properties were comparatively studied for activating PDS to degrade phenol. By integrating the computational and experimental results, the catalytic activity of BCN-NT/NS was determined to not only be related to the contents of heteroatom dopants (B and N), but also the positions of B and N in the co-doping configurations. This study offers reliable criteria for determining the intrinsic catalytic sites in carbocatalysts for the activation of PDS based on an electron-transfer mechanism, which assists the rational design of nanocarbons as advanced catalysts for metal-free oxidation and water remediation.
研究领域:
环境化学
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催化
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材料科学
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水处理
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高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
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2023
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IF 4.3
Cong Chen,Chengpiao Lu,Fang Li,Haibo Wang,Shuai Peng,Guoqiang Xu,Hongrui Xu,Jia-Bin Li
Graphical A total chemical synthesis strategy utilizing UFM1 C-terminal valine hydrazide as a versatile handle is reported for the facile preparation of UFM1-derived probes. This approach allows the convenient installation of electrophilic warheads, fluorescent reporters and unnatural purification tags onto the UFM1 sequence. Ufmylation is involved in various cellular processes and associated with many human diseases. The understanding of this modification relies on the use of customized UFM1-derived probes for activity-based profiling of its related enzymes. This study presents a highly optimized total chemical synthesis for the generation of diverse UFM1-derived probes including UFM1-PA, Biotin-UFM1-PA and UFM1-AMC, in which a UFM1 C-terminal valine hydrazide was readily prepared by hydrazide-based ligation and used as a versatile handle for the installation of enzyme-sensitive warheads and fluorescent reporters. The resulting probes display high reactivity and selectivity for UFM1-specific enzymes in cell lysates. This strategy facilitates the generation and diversity of the UFM1-derived toolkit that can be employed to profile UFM1-specific enzymes, thereby shining insights into the dynamics of ufmylation.
研究领域:
化学
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生物化学
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分子生物学
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细胞生物学
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医学
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PubMed
高影响因子
Journal of Functional Foods
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2021
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IF 4.451
Xiang-Rong Cheng,Piao-Han Tu,Wen-Le Dong,Bu-Tao Yu,Shu-Fang Xia,Mitchell N. Muskat,Bin Guan
Xiaoheiyao , the rhizomes of Inula nervosa Wall., is a culinary spice known to contain some electrophilic Nrf2 activators that could potentially intervene in nonalcoholic fatty liver disease (NAFLD). In this study, the electrophilic components from Xiaoheiyao were annotated by comprehensive cheminformatics analyses on UHPLC-MS/MS data after being knocked out with glutathione (GSH)-immobilized magnetic microspheres. Their intervention effects against hepatic steatosis were investigated in free fatty acid (FFA)-treated HepG2 cells. The electrophilic components in Xiaoheiyao were found to be the major bioactive components preventing hepatic steatosis in FFA-treated HepG2 cells. In particular, 10-isobutyryloxy-8,9-epoxythymol isobutyrate (XHY-1) improved hepatic lipid metabolism disorder, Krebs cycle activity, oxidative phosphorylation, and the cellular and mitochondrial redox status. Moreover, XHY-1 activates the Nrf2-ARE signaling pathway through the up-regulation of Nrf2 expression and promotion of Nrf2 nuclear translocation. Molecular docking further showed that XHY-1 could conjugate with Cys151 in the BTB domain of Keap1 through the epoxy group. In conclusion, the electrophilic components of Xiaoheiyao , especially XHY-1, attenuated hepatic steatosis in FFA-treated HepG2 cells through activation of the Nrf2-ARE signaling pathway.
研究领域:
药理学
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细胞生物学
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分子生物学
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药物化学
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DOI
高影响因子
危险品化学品经营许可证（带存储）