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Chinese Journal of Chemical engineering 2024年第5期69卷 212-219页

作者： Guangxia Jin Yuxue Wu Feng Wei school of biological and Chemical engineering NingboTech UniversityNingbo 315100China

The isolation of minor components from complex natural product matrices presents a significant challenge in the field of purification science due to their low concentrations and the presence of structurally similar *** study introduces an optimized twin-column recycling chromatography method for the efficient and simultaneous purification of these elusive *** introducing water at a small flowing rate between the twin columns,a step solvent gradient is created,by which the leading edge of concentration band would migrate at a slower rate than the trailing edge as it flowing from the upstream to downstream ***,the band broadening is counterbalanced,resulting in an enrichment effect for those minor components in separation ***,two target substances,which showed similar peak position in high performance liquid chromatography(HPLC)and did not exceed 1.8%in crude paclitaxel were selected as target compounds for *** using the twin-column recycling chromatography with a step solvent gradient,a successful purification was achieved in getting the two with the purity almost 100%.We suggest this method is suitable for the separation of most components in natural produces,which shows higher precision and recovery rate compared with the common lab-operated separation ways for natural products(thin-layer chromatography and prep-HPLC).

关键词： Solvent gradient Twin-column recycling chromatography Purification Minor component Natural products

Taxonomic dependency and spatial heterogeneity in assembly mechanisms of bacteria across complex coastal waters

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Ecological Processes 2024年第1期13卷 80-97页

作者： Huizhen Yan Dandan Lin Gaoke Gu Yujie Huang Xuya Hu Zhenhao Yu Dandi Hou Demin Zhang Barbara J.Campbell Kai Wang State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-Products School of Marine SciencesNingbo University Key Laboratory of marine Biotechnology of Zhejiang Province School of Marine Sciences Ningbo University Department of biological Sciences Clemson University

Background Understanding community assembly mechanisms across taxa and space is fundamental for microbial ecology. However, the variability and determinants of assembly processes over taxa and space remain unclear. Here, we investigated taxonomic dependency and spatial heterogeneity in bacterial assembly mechanisms across coastal waters in the East China Sea using neutral and null models with customized visualization *** Overall, bacterial assembly mechanisms varied across broad taxonomic groups(phyla and proteobacterial classes) and space at the regional scale. A determinism–stochasticity balanced mechanism governed total bacterial assembly, while taxonomic dependency existed in assembly mechanisms and ecological processes. Among community ecological features, niche breadth and negative-to-positive cohesion ratio were strongly associated with the determinism-to-stochasticity ratio of bacterial groups. Bacterial assembly mechanisms commonly exhibited spatial heterogeneity, the extent and determinants of which varied across taxonomic groups. Spatial assembly of total bacteria was directly driven by many environmental factors and potential interactions between taxa, but not directly by geographic factors. Overall, the bacterial groups with higher spatial heterogeneity in assembly mechanisms were more related to environmental and/or geographic factors(except Bacteroidetes), while those with lower heterogeneity were more related to ecological *** Our results confirm the pervasiveness of taxonomic dependency and spatial heterogeneity in bacterial assembly, providing a finer understanding about regulation across complex coastal waters.

关键词： Bacterioplankton Assembly mechanism Niche breadth Null model Environmental gradient Biogeography

An efficient approach for the treatment of radioactive waste perfluoropolyether lubricants via a synergistic effect of thermal catalysis and immobilization

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Journal of Environmental Sciences 2024年第2期136卷 512-522页

作者： Xinhang Du Wenhua Tong Xinyu Zhou Jia Luo Yuqiu Liu Yabo Wang Panyu Li Yongkui Zhang Department of Pharmaceutical&biological engineering School of Chemical EngineeringSichuan UniversityChengdu 610065China

Perfluoropolyether(PFPE)lubricants are a kind of high-molecular polymer with many excellent ***,the use of PFPEs in the nuclear industry can lead to partial decomposition and carrying radionuclides,resulting in a large amount of radioactive waste PFPE lubricants ***,radioactive waste PFPE lubricants are difficult to be effectively treated due to their high stability,the risk of possible leakage of radionuclides,and hypertoxic fluorine-containing *** this study,without any precedent,a strategy of Mn O_(2)-catalyzed decomposition and Na_(2)CO_(3)-immobilized conversion was proposed for PFPE lubricant decomposition and fluorine immobilization simultaneously based on the Lewis acid-base and oxygen vacancies concept.A high fluorine conversion efficiency of 95.4%was ***,the mechanism of decomposition suggested that Mn O_(2)mainly provided Lewis acid sites and attacked the(basic)fluorine or oxygen atoms in PFPE *** decomposition of PFPE chains was proceed down and volatile fluorine-containing gas was released by partial electron transfer,intramolecular disproportionation reaction,and unzipping ***,gas by-products could be further oxidized and then immobilized into fluoride salts by carbonate solid ***,this study provides a simple,safe,and potentially practical strategy for the harmless conversion of refractory fluorinated organic wastes,especially perfluoropolymers.

关键词： Perfluoropolyether lubricants Catalyzed decomposition Fluorine-containing gas Immobilized conversion Fluoride

Facet effects on bimetallic ZnSn hydroxide microcrystals for selective electrochemical CO2 reduction

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Green Energy & Environment 2024年第8期9卷 1314-1320页

作者： Liu Han Cheng-wei Wang Shan-shan Luo Ying-tang Zhou Bing Li Ming Liu school of Chemistry and Chemical engineering Harbin Institute of Technology National engineering Research Center for marine Aquaculture Marine Science and Technology CollegeZhejiang Ocean University

Employing crystal facets to regulate the catalytic properties in electrocatalytic carbon dioxide reduction reaction（eCO2RR） has been well demonstrated on electrocatalysts containing single metals but rarely explored for bimetallic systems. Here, we synthesize Zn Sn（OH）6（ZSO）microcrystals（MCs） with distinct facets and investigate the facet effects in eCO2RR. Electrochemical studies and in situ Fourier Transform Infrared Spectroscopy（in situ-FTIR） reveal that ZSO MCs produce mainly C1 products of HCOOH and CO. The {111} facet of the ZSO MCS exhibits higher selectivity and faradaic efficiency（FE） than that of the {100} facet over a wide range of potentials（-0.9 V ～-1.3 V versus RHE）. Density Functional Theory（DFT） calculations elucidate that the {111} facet is favorable to the adsorption/activation of CO2molecules,the formation of intermediate in the rate-determining step, and the desorption of C1 products of CO and HCOOH molecules.

关键词： ZnSn(OH) 6 Crystal facets Electrochemical carbon dioxide reduction C1 product Density functional theory

Stability and transepithelial transport of oligopeptide(KRQKYD)with hepatocyte-protective activity from Jinhua ham in human intestinal Caco-2 monolayer cells

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Food Science and Human Wellness 2024年第3期13卷 1503-1512页

作者： Wen Nie Feiran Xu Kai Zhou Jieying Deng Ying Wang Baocai Xu engineering Research Center of Bio-process Ministry of EducationSchool of Food and Biological EngineeringHefei University of TechnologyHefei 230601China school of biological and Food engineering Chuzhou UniversityChuzhou 239001China

The study evaluated the stability of an oligopeptide(Lys-Arg-Gln-Lys-Tyr-Asp,KRQKYD)and its transport mechanism by simulating gastrointestinal digestion and a model of human intestinal Caco-2 monolayer cells in *** this study,the effects of environmental factors(temperature,pH and NaCl concentration)and simulated gastrointestinal digestion on the stability of KRQKYD were evaluated by indicators of the levels of alanine transaminase(ALT),aspartate transaminase(AST)and malondialdehyde(MDA)in an alcoholinduced hepatocyte injury *** results showed that KRQKYD still maintained satisfactory hepatocyteprotective activity after treatment with different temperatures(20-80℃),pH(3.0-9.0),NaCl concentration(1%-7%)and simulated gastrointestinal digestion,which indicated that KRQKYD showed good stability to environmental factors and simulated gastrointestinal ***,the intact KRQKYD could be absorbed in a model of Caco-2 monolayer cells with a P_(app)value of(9.70±0.53)×10^(-7)cm/*** with an energy inhibitor(sodium azide),a competitive peptide transporter inhibitor(Gly-Pro)and a transcytosis inhibitor wortmannin did not decrease the level of transepithelial KRQKYD transport,indicating that the transport mechanism of KRQKYD was not associated with energy dependent,vector mediated and *** tight junction disruptor cytochalasin D significantly increased the level of transepithelial KRQKYD transport(P<0.05),suggesting that intact KRQKYD was absorbed by paracellular transport.

关键词： Jinhua ham KRQKYD(Lys-Arg-Gln-Lys-Tyr-Asp) Environmental stability Gastrointestinal digestive Transport mechanism

Additives strategies to improving cycling stability of Li metal batteries by modifying electrode electrolyte interphases

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Progress in Natural Science:Materials International 2024年第2期34卷 338-344页

作者： Yuan Li Pengfei Huang Chunyu Cui Xiaoyuan Ma Li Chen Zekun Li Linhai Li Yuhong Tian school of biological and Chemical engineering Guangxi University of Science and Technology school of College of Chemistry and Chemical engineering Hunan University Isky Future Energy Institute

Li metal batteries（LMBs） have attracted much attention due to the ultra-high theoretical capacity of the Li metal anode（LMA）.However,the uncontrollable dendrites growth and low coulombic efficiency hinder their practical ***,we explore 3,5-difluoropyridine（2F-BD） as a novel electrolyte additive to enable highperformance *** 2F-BD additive participates in and modifies the solvation structure of Li ions by reducing the coordinated number of PF6-at the electrode surface,leading to the formation of a LiF and Li3N-rich solid electrolyte interphase（SEI）.The LiF component increases the robustness of SEI and suppresses the formation of Li dendrites,while the Li3N component facilitates the transportation and reaction kinetics of Li *** a result,the Li‖Li symmetric cell presents a stable cycling performance of up to 500 h at a current density of 1 mA *** coupling with LiFePO4cathode,the obtained full cell achieves high specific capacities of 106.06 mA h g-1and 84.98 mA h g-1at 2.55 mA cm-2and 5.10 mA cm-2,respectively,and maintains a high capacity retention of84.0% after 1000 cycles at 0.13 mA cm-2,with an average cycling CE of 99.58%.

关键词： Electrolyte additive Li dendrites Li metal batteries LiF and Li3N-Rich electrode-electrolyte interphase LiFePO4 cathode

Characterization,Expression Pattern Analysis,and Cellular Localization of Two Homologous MUC2 Genes in Japanese Flounder(Paralichthys olivaceus)

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Journal of Ocean University of China 2024年第4期23卷 1035-1044页

作者： ZHU Ying YANG Xinsheng LI Zhengjie LI Chao school of marine Science and engineering Qingdao Agricultural UniversityQingdao 266109China

As a member of mucins family,MUC2 is an important component of mucus,which is characterized by tandem and irregular repeat sequences rich in threonine and *** is strongly expressed by goblet cells that are involved in innate *** flounder is an economically important marine *** this study,two homologous genes of MUC2 were identified,named MUC2-1 and *** on phylogenetic and structural analysis,MUC2-1 and MUC2-2 were clustered in two clades,*** olivaceus MUC2-1 showed a closer relationship with MUC2 in the higher *** healthy tissues were analyzed to determine the expression patterns,and both MUC2 genes showed high expression levels in the gills and *** Edwardsiella tarda challenge,*** MUC2-1 and MUC2-2 both showed significant up-regulated expression in intestine and ***,MUC2-1 was significantly up-regulated in gill cell lines following PGN and polyI:C stimulation,and MUC2-2 was significantly up-regulated in gill cell lines following LPS *** addition,ISH results revealed that MUC2-1 and MUC2-2 showed the same tissue localization in intestine tissues,but displayed different localization in *** siRNA-mediated knockdown of MUC2-1 and MUC2-2 genes in the gill cell lines of Japanese flounder affected the expressions of galnt family genes and smad pathway members that are related to mucosal *** results provided a valuable insight into understanding the functions of MUC2 on mucosal immune system in response to the invasion of bacterial pathogen.

关键词： MUC2 ISH Edwardsiella tarda Paralichthys olivaceus

Proteomics Study of Benzene Metabolite Hydroquinone Induced Hematotoxicity in K562 Cells

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Biomedical and Environmental Sciences 2024年第4期37卷 341-353页

作者： JIN Yi Shan YI Zong Chun ZHANG Yu Jing RONG Long YU Chun Hong school of biological Science and Medical engineering Beihang UniversityBeijing 100191China school of engineering Medicine Beihang UniversityBeijing 100191China

Objective Hydroquinone(HQ),one of the phenolic metabolites of benzene,is widely recognized as an important participant in benzene-induced ***,there are few relevant proteomics in HQ-induced hematotoxicity and the mechanism hasn’t been fully understood *** In this study,we treated K562 cells with 40μmol/L HQ for 72 h,examined and validated protein expression changes by Label-free proteomic analysis and Parallel reaction monitoring(PRM),and performed bioinformatics analysis to identify interaction *** One hundred and eighty-seven upregulated differentially expressed proteins(DEPs)and 279 downregulated DEPs were identified in HQ-exposed K562 cells,which were involved in neutrophilmediated immunity,blood microparticle,and other GO terms,as well as the lysosome,metabolic,cell cycle,and cellular senescence-related *** on the 23 DEGs and 5 DEPs in erythroid differentiation-related pathways,we constructed the network of protein interactions and determined 6 DEPs(STAT1,STAT3,CASP3,KIT,STAT5B,and VEGFA)as main hub proteins with the most interactions,among which STATs made a central impact and may be potential biomarkers of HQ-induced *** Our work reinforced the use of proteomics and bioinformatic approaches to advance knowledge on molecular mechanisms of HQ-induced hematotoxicity at the protein level and provide a valuable basis for further clarification.

关键词： Hydroquinone Proteomics Hematotoxicity K562 cells

Lipase and photodecarboxylase coexpression: A potential strategy for alkane-based biodiesel production from natural triglycerides

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Chinese Journal of Chemical engineering 2024年第3期67卷 238-246页

作者： Yong-Yi Zeng Xin-Yi Xu Jin-Xuan Xie Wen-Li Chen Lan Liu Xin-Jian Yin Bi-Shuang Chen school of marine Sciences Sun Yat-Sen UniversityZhuhai 519080China Southern marine Science and engineering Guangdong Laboratory(Zhuhai) Zhuhai 519080China

Alkane-based biodiesel is considered the next generation of biodiesel owing to its potential environmental benefits and the fact that it exhibits much higher specific caloric values than traditional ***,the formidable obstacle impeding the commercialization of this cutting-edge fuel alternative lies in the cost associated with its *** this study,an engineered strain Escherichia coli(***)showcasing harmonized coexpression of a lipase(from Thermomyces lanuginosus lipase,TLL)and a fatty acid photodecarboxylase(from Chlorella variabilis,CvFAP)was first constructed to transform triglycerides into *** potential of *** BL21(DE3)/pRSFDuet-1-TLL-CvFAP for alkane synthesis was evaluated with tripalmitin as a model substrate under various process *** a comprehensive examination of the reaction parameters,the scope of the biotransformation was expanded to‘real’substrates(vegetable oils).The results showed that bioderived oils can be transformed into alkanes with high yields(0.80-10.20 mmol·L^(-1))under mild conditions(35℃,pH 8.0,and 36 h)and blue light *** selected processes were performed on an increased lab scale(up to 100 ml)with up to 24.77 mmol·L^(-1) tripalmitin,leading to a yield of 18.89 mmol·L^(-1) *** the employment of a method for efficiently producing alkanes under mild conditions and a simple procedure to isolate alkanes from the reaction system,the utilization of sustainable biomass as a fundamental feedstock emerges as the primary solution to lower the cost of alkane-based ***,this study proposes a readily implementable and highly effective approach for alkane-based biodiesel production.

关键词： Alkane-based biodiesel Renewable biomass Co-overexpression Lipase Photodecarboxylase

Design of highly active and durable oxygen evolution catalyst with intrinsic chlorine inhibition property for seawater electrolysis

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Nano Materials Science 2024年第4期6卷 413-418页

作者： Jieli Chen Xiaodong Shi Suyang Feng Jing Li Xiaohong Gao Xiao Wu Ke Li Anyuan Qi Chenghang You Xinlong Tian school of marine Science and engineering School of Chemical Engineering and Technology Hainan University National Energy Group Ledong Power Generation Co. Ltd

High-efficiency seawater electrolysis is impeded by the low activity and low durability of oxygen evolution catalysts due to the complex composition and competitive side reactions in ***,a heterogeneousstructured catalyst is constructed by depositing NiFe-layered double hydroxides （NiFe-LDH） on the substrate of MXene （V2CTx） modified Ni foam （NF）,and abbreviated as NiFe-LDH/V2CTx/*** demonstrated,owing to the intrinsic negative charge characteristic of V2CTx,chlorine ions are denied entry to the interface between NiFeLDH and V2CTx/NF substrate,thus endowing NiFe-LDH/V2CTx/NF catalyst with high corrosion resistance and durable stability for 110 h at 500 mA ***,the two-dimensional structure and high electrical conductivity of V2CTxcan respectively enlarge the electrochemical active surface area and guarantee fast charge transfer,thereby synergistically promoting the catalytic performance of NiFe-LDH/V2CTx/NF in both deionized water electrolyte (261 m V at 100 m A cm-2) and simulated seawater electrolyte (241 mV at 100 mA cm-2).This work can guide the preparation of oxygen evolution catalysts and accelerate the industrialization of seawater electrolysis.

关键词： NiFe-LDH/V 2 CT x /NF catalyst Oxygen evolution reaction Seawater electrolysis Chlorine inhibition