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Advances and challenges in the synthesis of N-fluoroalkyl compounds
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作者 Lvqi Jiang Wenbin Yi 《Science China Chemistry》 2026年第2期535-538,共4页
The incorporation of small fluorinated functional groups,including CF_(3),CF_(2)H,and CFH_(2),into small molecules represents a crucial strategy for modulating their physical,chemical,and biological characteristics[1,... The incorporation of small fluorinated functional groups,including CF_(3),CF_(2)H,and CFH_(2),into small molecules represents a crucial strategy for modulating their physical,chemical,and biological characteristics[1,2].Consequently,organofluorine compounds are frequently encountered in pharmaceuticals and agrochemicals.Significant advances have been made in the introduction of fluoroalkyl groups into small molecules since the beginning of the 21st century. 展开更多
关键词 introduction fluoroalkyl groups incorporation small fluorinated functional groupsincluding synthesis N fluoroalkyl compounds fluoroalkyl compounds fluorinated functional groups CF H small molecules
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Generation of coffee flavor compounds from fresh cherry to cup: deciphering the contribution of microbiota metabolism
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作者 Kaihua Lu Ya He +8 位作者 Yu Cao Tong Zhu Qinming Liu Beining Liu Yi Duan Yongxiu Zhou Fang Yang Hong Li Yongjin Hu 《Journal of Future Foods》 2026年第6期1071-1083,共13页
This study explores the impact of coffee flavor influenced by fermentation,microorganisms,and flavor precursors.The microbial processes during fermentation and the resulting chemical transformations were given special... This study explores the impact of coffee flavor influenced by fermentation,microorganisms,and flavor precursors.The microbial processes during fermentation and the resulting chemical transformations were given special attention.The composition and metabolic functions of microbial populations were found to play a crucial role in modifying the composition of coffee beans,leading to the diverse flavors observed in coffee.To control fermentation and enhance the flavor profile of coffee,a clear understanding of microorganisms' roles in fermentation is necessary.Identifying suitable microbial strains for coffee fermentation is essential for developing fermentation techniques that produce high-quality coffee tailored to the taste preferences of different demographics. 展开更多
关键词 COFFEE Fermentation YEAST Bacteria METABOLITES Flavor precursors Flavor compounds MICROBIOTA
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Visible-light-promoted multi-component carbene transfer reactions of diazo compounds via ring-opening of cyclic ethers
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作者 Feng Zhao Hongyu Ding +4 位作者 Ting Sun Chao Shen Zu-Li Wang Wei Wei Dong Yi 《Chinese Chemical Letters》 2026年第2期206-217,共12页
Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable ... Carbenes as one of the most important class of intermediates have been widely utilized in various organic synthetic transformations.Carbene insertion-initiated ring-opening reactions of cyclic ethers offer a valuable strategy for constructing new carbon-oxygen bonds.In comparison with traditional thermal or metal-mediated carbene transfer reactions,visible-light-promoted multi-component reaction strategy provides a mild and eco-friendly approach to access densely functionalized molecules.Recently,visible-light-induced multi-component carbene transfer reactions of diazo compounds have been rapidly developed and attracted a great deal of research interest of chemists owing to their advantages of simple operation,mild condition,high atom economy and rich structural diversity.This paper summarizes the recent research progress on the visible-light-promoted multi-component carbene transfer reactions of diazo compounds via ring-opening of cyclic ethers with various nucleophiles.The reaction patterns of different nucleophiles and their corresponding mechanism are described in this review.The future research direction and challenges in this area are also discussed. 展开更多
关键词 VISIBLE-LIGHT Multi-component reaction Carbene insertion Diazo compounds Ring-opening reaction
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Advanced applications of synthetic biology technology in biosynthesis of bioactive compounds from medicinal plants
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作者 Yingjun Liu Anying Ji +1 位作者 Haiyang Ji Huan Sun 《Chinese Herbal Medicines》 2026年第1期11-28,共18页
Medicinal plants serve as valuable sources of bioactive compounds with critical applications across pharmaceutical,agricultural,and industrial sectors.Compared to chemical synthesis and plant extraction,synthetic biol... Medicinal plants serve as valuable sources of bioactive compounds with critical applications across pharmaceutical,agricultural,and industrial sectors.Compared to chemical synthesis and plant extraction,synthetic biology offers a green,efficient,and sustainable alternative for producing bioactive compounds,which represents a state of art technology.However,this technology still faces several challenges,including overly long metabolic pathways,inadequate catalytic efficiency of key enzymes in the pathway,and incompatibility between gene elements and host cells,leading to low yields of target bioactive compounds.The development and application of regulatory tools in synthetic biology hold great promise for overcoming these obstacles.This review first summarizes the classification and biosynthesis of bioactive compounds based on structural types.Subsequently,recent advancements are outlined in regulation tools and their application in the heterologous production of bioactive compounds.This review aims to establish a foundation for the efficient production of bioactive compounds based on microbial cell factories.This not only has significant practical implications for reducing the resource consumption and environmental impact of traditional production methods,but also highlights the central role of synthetic biology in promoting the sustainable production of bioactive compounds derived from medicinal plants. 展开更多
关键词 bioactive compounds medicinal plants metabolic engineering regulatory tools synthetic biology
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A sensitive method for rapid determination of 256 semi-volatile organic compounds(SVOCs)in water by solid-phase extraction and GC-MS/MS
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作者 Youchang Zhu Ruohan Sun +5 位作者 Yanran Dong Yan Liu Yupeng Chen Zhiquan Yuan Baozhu Pan Nan Xu 《Journal of Environmental Sciences》 2026年第1期362-373,共12页
A trace analytical method based on solid-phase extraction gas chromatography-tandem mass spectrometry(SPE–GC–MS/MS)was developed for the rapid detection of 256 semi-volatile organic compounds(SVOCs),including 25 pol... A trace analytical method based on solid-phase extraction gas chromatography-tandem mass spectrometry(SPE–GC–MS/MS)was developed for the rapid detection of 256 semi-volatile organic compounds(SVOCs),including 25 polycyclic aromatic hydrocarbons(PAHs),70 polychlorinated biphenyls(PCBs),123 pesticides,20 phthalate esters(PAEs),4 organophosphate esters(OPEs),9 synthetic musks(SMs),and 5 UV filters(UVs)in water.No-tably,this method provided a decent linearity of calibration standards(R^(2)>0.999),excellent method limits of quantification(MLOQs)(0.12–11.41 ng/L),satisfactory matrix spiking recovery rates(60.4%–126%),and high precision(intra-day relative standard deviations(RSDs):1.0%–10.0%,inter-day RSDs:3.0%–15.0%,and inter-week RSDs:3.4%–15.7%),making it suitable for trace-level studies.Statistical analysis revealed that SVOCs with higher volatility exhibited enhanced recovery rates.Validation of the methodology involved analyzing SVOCs in real spring water and river water samples.Twenty-seven SVOCs were detected in spring water and 58 in river water,with an average concentration of 631.73 and 16,095 ng/L,respectively.Among the detected SVOCs,PAEs constituted the predominant proportion.This study underscored the presence of SVOCs contamination specifi-cally within the spring water,although SVOCs concentrations in river water were significantly greater than those found in spring water.In summary,this sensitive method based on SPE–GC–MS/MS was successfully developed and validated for the rapid analysis of a diverse array of 256 SVOCs at trace levels in water,including not only the traditional highly valued PAHs,PCBs,pesticides,and PAEs,but also the emerging OPEs,UVs,and SMs. 展开更多
关键词 Semi-volatile organic compounds Spring water GC-MS/MS Organophosphate esters Synthetic musks UV filters
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Constructing a high-performance magnesium single-atom catalyst for the transfer hydrogenation of biomass-derived carbonyl compounds in ethanol
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作者 Lei Hu Mengxue Liu +5 位作者 Baogang Sha Jiacheng Li Aiyong He Xing Tang Zhen Wu Lu Lin 《Journal of Energy Chemistry》 2026年第1期517-531,I0012,共16页
Endogenous hydrogen systems,consisting of metal–organic coordination catalysts and alcohols,have been widely applied for the transfer hydrogenation(TH)of biomass-derived carbonyl compounds in recent years.Metal-organ... Endogenous hydrogen systems,consisting of metal–organic coordination catalysts and alcohols,have been widely applied for the transfer hydrogenation(TH)of biomass-derived carbonyl compounds in recent years.Metal-organic coordination catalysts showed satisfactory ability of TH in the secondary alcohols,but most of them could not effectively employ the cheaper primary alcohols as hydrogen donors.Furthermore,they commonly contained high metal contents,which also led to low catalytic efficiency in significant measure.In this work,we constructed a novel magnesium single-atom catalyst(Mg-NC)with merely 0.37 wt%Mg by means of a combined self-assembly and pyrolysis strategy.The characterization results indicated that Mg was atomically dispersed and it was coordinated with four pyridinic-N in Mg-NC.Due to the obvious electron transfer from Mg to its coordinated pyridinic-N,Mg–N_(4)active centers displayed high Lewis acid-base strength with abundant content,which brought remarkable catalytic activity.When Mg-NC was used for the TH of 5-hydroxymethylfurfural(HMF)in ethanol(EtOH),2,5-bis(hydroxymethyl)furan(BHMF)yield was up to 96.3%with high productivity of 19.85 molBHMF mol_(Mg)^(−1)h^(−1)at 150°C for 5 h.More interestingly,the process of TH over Mg-NC in EtOH was proved to proceed via the hydrogen radical mechanism.Additionally,Mg-NC exhibited powerful catalytic universality;it could not only utilize other primary alcohols(such as n-propanol and n-butanol)as hydrogen donors,but also catalyze the TH of other carbonyl compounds(such as furfural,5-methylfurfural,benzaldehyde,cyclohexanone,and levulinic acid).Overall,this work offered some important clues and references to reinforce the hydrogen-supplying ability of primary alcohols in the TH of various biomass-derived carbonyl compounds to high-value fine chemicals. 展开更多
关键词 Transfer hydrogenation Carbonyl compounds Primary alcohols Single-atom catalysts Lewis acid-base sites Synergistic effects
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Characterization,sources and reactivity of carbonyl volatile organic compounds in North China:Based on long-term observations
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作者 Ziyan Chen Kaitao Chen +4 位作者 Xingru Li Rongjie Li Zheng Li Bingyu Xiao Gehui Wang 《Journal of Environmental Sciences》 2026年第1期797-808,共12页
Carbonyl compounds play a pivotal role in the formation of secondary pollutants such as O_(3) and SOA,signifi-cantly impacting air quality and human health.This study extended the observation period compared to previo... Carbonyl compounds play a pivotal role in the formation of secondary pollutants such as O_(3) and SOA,signifi-cantly impacting air quality and human health.This study extended the observation period compared to previous research,providing a long-term perspective on carbonyl compound variations and their environmental implica-tions.Atmospheric observations were conducted at Beijing(BJ)and Xianghe(XH)during the summer and winter months of 2018,2019,and 2023 to study the sources and impacts of carbonyl compounds in typical urban areas and peri‑urban areas.Notably,concentrations in the summer of 2023 increased compared to 2018 and 2019.The predominant carbonyl compounds—formaldehyde,acetaldehyde,and acetone—accounted for over 60%of the total.The mean values of OFP in BJ ranged from 18.55 to 58.61μg/m3,lower than those in XH(29.82 to 65.48μg/m3),with formaldehyde and acetaldehyde contributing over 80%of the total.SOAP exhibited a similar pattern,with values in XH(69.21 to 508.55μg/m3)significantly exceeding those in BJ(34.47 to 159.78μg/m3).The PMF model highlighted vehicle exhaust,secondary pollution,and biomass combustion as major sources of carbonyl compounds,emphasizing differences in source contributions between the two regions.This study’s com-parative analysis over different years and locations provides new insights into the dynamic changes in carbonyl compounds and their environmental importance.These results not only reinforce the importance of carbonyl compounds regulation but also offer a valuable reference for evaluating and refining emission control strategies during this period. 展开更多
关键词 Carbonyl compounds Ozone formation potential Secondary organic aerosol formation potential Source resolution
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Emission characteristics and probabilistic health risk of volatile organic compounds from leather sofa 被引量:3
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作者 Chuanhui Mu Yuling Tang +2 位作者 Zhaohui Yang Jianfei Zhou Bi Shi 《Journal of Environmental Sciences》 2025年第2期79-87,共9页
Furniture is identified as a vital volatile organic compound(VOC)emission source in the indoor environment.Leather has become the most common raw and auxiliary fabric material for upholstered furniture,particularly wi... Furniture is identified as a vital volatile organic compound(VOC)emission source in the indoor environment.Leather has become the most common raw and auxiliary fabric material for upholstered furniture,particularly with extensive consumption in sofas,due to its abundant resources and efficient functions.Despite being widely traded across the world,little research has been conducted on the VOCs released by leathermaterials and their health risk assessment in the indoor environment.Accordingly,this study investigated the VOC emissions of leather with different grades and the health risk of the inhalation exposure.Based on the ultra-fast gas phase electronic nose(EN)and GC-FID/Qtof,the substantial emissions of aliphatic aldehyde ketones(Aks),particularly hexanal,appear to be the cause of off-flavor in medium and low grade(MG and LG)sofa leathers.The health risk assessment indicated that leather materials barely pose non-carcinogenic and carcinogenic effects to residents.Given the abundance of VOC sources and the accumulation of health risks in the indoor environment,more stringent specifications concerning qualitative and quantitative content should be extended to provide VOC treatment basic for the manufacturing industry and obtain better indoor air quality. 展开更多
关键词 Indoor environment LEATHER Volatile organic compounds(VOCs) Health risk assessment
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Characterization and source apportionment of volatile organic compounds in Hong Kong:A 5-year study for three different archetypical sites 被引量:2
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作者 Yuchen Mai Vincent Cheung +5 位作者 Peter K.K.Louie Kenneth Leung Jimmy C.H.Fung Alexis K.H.Lau Donald R.B.lake Dasa Gu 《Journal of Environmental Sciences》 2025年第5期424-440,共17页
Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ... Initial success has been achieved in Hong Kong in controlling primary air pollutants,but ambient ozone levels kept increasing during the past three decades.Volatile organic compounds(VOCs)are important for mitigating ozone pollution as its major precursors.This study analyzed VOC characteristics of roadside,suburban,and rural sites in Hong Kong to investigate their compositions,concentrations,and source contributions.Herewe showthat the TVOC concentrations were 23.05±13.24,12.68±15.36,and 5.16±5.48 ppbv for roadside,suburban,and rural sites between May 2015 to June 2019,respectively.By using Positive Matrix Factorization(PMF)model,six sources were identified at the roadside site over five years:Liquefied petroleum gas(LPG)usage(33%–46%),gasoline evaporation(8%–31%),aged air mass(11%–28%),gasoline exhaust(5%–16%),diesel exhaust(2%–16%)and fuel filling(75–9%).Similarly,six sources were distinguished at the suburban site,including LPG usage(30%–33%),solvent usage(20%–26%),diesel exhaust(14%–26%),gasoline evaporation(8%–16%),aged air mass(4%–11%),and biogenic emissions(2%–5%).At the rural site,four sources were identified,including aged airmass(33%–51%),solvent usage(25%–30%),vehicular emissions(11%–28%),and biogenic emissions(6%–12%).The analysis further revealed that fuel filling and LPG usage were the primary contributors to OFP and OH reactivity at the roadside site,while solvent usage and biogenic emissions accounted for almost half of OFP and OH reactivity at the suburban and rural sites,respectively.These findings highlight the importance of identifying and characterizing VOC sources at different sites to help policymakers develop targeted measures for pollution mitigation in specific areas. 展开更多
关键词 Volatile organic compounds Positive matrix factorization Source apportionment Ozone formation
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Variation of Heteroatomic Compounds from the First Member of the Upper Cretaceous Qingshankou Formation in the Sanzhao Sag,Songliao Basin(NE China)using ESI FT-ICR MS and its Shale Oil Geological Significance 被引量:2
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作者 XIAO Fei YANG Jianguo +3 位作者 YAO Yulai LI Shichao HUANG Yiming GAO Xiaoyong 《Acta Geologica Sinica(English Edition)》 2025年第3期840-861,共22页
Organic-rich mudstones and shales,which hold significant potential for shale oil resources,characterize the first member of the Upper Cretaceous Qingshankou Formation(K_(2)qn~1)in the Sanzhao sag of the Songliao Basin... Organic-rich mudstones and shales,which hold significant potential for shale oil resources,characterize the first member of the Upper Cretaceous Qingshankou Formation(K_(2)qn~1)in the Sanzhao sag of the Songliao Basin,NE China.Focusing on 30 core samples obtained from the first shale oil parameter well,named SYY3 in the study area,we systematically analyzed the composition and stratigraphic distribution of the K_(2)qn~1 heteroatomic compounds using electrospray ionization Fourier transform-ion cyclotron resonance mass spectrometry(ESI FT-ICR MS),to assess their geological relevance to shale oil.The findings indicate that in the negative ion mode,the heteroatomic compounds predominantly consist of N_(1),N_(1)O_(1)-N_(1)O_(8),O_(1)-O_(8),O_(1)S_(1)-O_(6)S_(1);contrastingly,in the positive ion mode,they are primarily composed of N_(1)-N_(2),N_(1)O_(1)-N_(1)O_(4),N_(2)O_(1),O_(1)-O_(4),O_(1)S_(1)-O_(2)S_(1).Heteroatomic compound distributions vary significantly with depth in the negative ion mode,with minor variations in the positive ion mode.These distributions are categorized into three types based on the negative ion ratio((N_(1)+N_(1)O_(x))/O_(x)):TypeⅠ(>1.5),TypeⅡ(0.8-1.5),and TypeⅢ(<0.8);typesⅠandⅡgenerally exhibit a broader range of carbon numbers compared to TypeⅢ.The distribution of double bond equivalent(DBE)values across various sample types exhibits minimal variance,whereas that of carbon numbers shows substantial differences.Variations in heteroatomic compound compositions among the samples might have resulted from vertical sedimentary heterogeneity and differing biotic contributions.TypeⅢsamples show a decrease in total organic carbon(TOC)and free oil content(S_(1))compared to typesⅠandⅡ,but an increased oil saturation index(OSI),indicating a lower content of free oil but a higher proportion of movable oil.The reduced content of N-containing compounds implies lower paleolake productivity during deposition,leading to a reduction in TOC and S_(1).A lower TOC can enhance oil movability due to reduced oil adsorption,and the decreased presence of polar nitrogenous macromolecules with fewer highC-number heteroatomic compounds further promote shale oil movability.Additionally,the negative ion ratios of N1/N1O1and O2/O1 exhibit positive and negative correlations with the values of TOC,S_(1),and extractable organic matter(EOM),respectively,indicating that the salinity and redox conditions of the depositional water body are the primary controlling factors for both organic matter enrichment and shale oil accumulation. 展开更多
关键词 oil movability shale-oil enrichment heteroatomic compounds Qingshankou Formation Sanzhao sag Songliao Basin
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Effects of photo-oxidation and transition metals on the formation of reactive oxygen species from aromatic compounds using spectroscopic method 被引量:1
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作者 Xiaoyu Hu Juanjuan Qin +5 位作者 Yuanyuan Qin Tianyi Zhao Yuxuan Cao Qinghe Cai Lijia Zhang Yang Zhang 《Journal of Environmental Sciences》 2025年第5期1-11,共11页
Particulate matter(PM)can cause adverse health effects by overproducing reactive oxygen species(ROS).Although the ability of PM to induce ROS generation depends on its composi-tion and environmental factors.This study... Particulate matter(PM)can cause adverse health effects by overproducing reactive oxygen species(ROS).Although the ability of PM to induce ROS generation depends on its composi-tion and environmental factors.This study explores how photo-oxidation affects ROS gen-eration from aromatic compounds(ACs,including catechol(CAT),phthalic acid(PA),and 4,4-oxydibenzoic acid(4,4-OBA))and their mixtures with transition metals(TMs,includ-ing Fe(II),Mn(II),and Cu(II))using Fourier-transform infrared(FTIR)and Ultraviolet-visible spectroscopy(UV-Vis).Results showed that photo-oxidation facilitated ROS generation from ACs.CAT-Fe(II)/Cu(II)showed synergistic effects,but 4,4-OBA-Fe(II)/Cu(II)showed antag-onistic effects.ACs-Mn(II)and PA-Fe(II)/Cu(II)exhibited synergistic effects first and then showed antagonistic effects.The different interactions were due to complexation between ACs and TMs.The photo-oxidized ACs-TMs significantly enhanced ROS generation com-pared with ACs-TMs.The study suggested the photo-oxidation mechanism involved that the transfer ofπ-electrons from the ground to an excited state in benzene rings and func-tional groups,leading to the breakage and formation of chemical bonds or easierπ-electron transfer from ACs to TMs.The former could generate ROS directly or produce polymers that promoted ROS generation,while the latter promoted ROS generation by transferringπ-electrons to dissolved oxygen quickly.Our study revealed that both interactions among components and photo-oxidation significantly influenced ROS generation.Future studies should integrate broader atmospheric factors and PM components to fully assess oxidative potential and health impacts. 展开更多
关键词 Reactive oxygen species Aromatic compounds Transitional metals PHOTO-OXIDATION
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Chemical characteristics and sources apportionment of volatile organic compounds in the primary urban area of Shijiazhuang,North China Plain 被引量:2
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作者 Xiao Zhang Junfeng Wang +8 位作者 Jiangwei Zhao Junliang He Yali Lei Kai Meng RuiWei Xue Zhang Miaomiao Zhang Shuangying Ni Eleonora Aruffo 《Journal of Environmental Sciences》 2025年第3期465-475,共11页
VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effe... VOCs(Volatile organic compounds)exert a vital role in ozone and secondary organic aerosol production,necessitating investigations into their concentration,chemical characteristics,and source apportionment for the effective implementation of measures aimed at preventing and controlling atmospheric pollution.FromJuly to October 2020,onlinemonitoringwas conducted in the main urban area of Shijiazhuang to collect data on VOCs and analyze their concentrations and reactivity.Additionally,the PMF(positive matrix factorization)method was utilized to identify the VOCs sources.Results indicated that the TVOCs(total VOCs)concentration was(96.7±63.4μg/m^3),with alkanes exhibiting the highest concentration of(36.1±26.4μg/m^3),followed by OVOCs(16.4±14.4μg/m^3).The key active components were alkenes and aromatics,among which xylene,propylene,toluene,propionaldehyde,acetaldehyde,ethylene,and styrene played crucial roles as reactive species.The sources derived from PMF analysis encompassed vehicle emissions,solvent and coating sources,combustion sources,industrial emissions sources,as well as plant sources,the contribution of which were 37.80%,27.93%,16.57%,15.24%,and 2.46%,respectively.Hence,reducing vehicular exhaust emissions and encouraging neighboring industries to adopt low-volatile organic solvents and coatings should be prioritized to mitigate VOCs levels. 展开更多
关键词 Volatile organic compounds Pollution characteristics Ozone formation potential OH radical loss rate Source apportionment
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Pathways of inhibition of filamentous sludge bulking by slowly biodegradable organic compounds 被引量:1
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作者 Chundi Gao Fan Yang +3 位作者 Zinan Tian Diyao Sun Weilin Liu Yongzhen Peng 《Journal of Environmental Sciences》 2025年第4期104-115,共12页
The organic compound composition ofwastewater,serves as a crucial indicator for the operational performance of activated sludge processes and has a major influence on the development of filamentous bulking in activate... The organic compound composition ofwastewater,serves as a crucial indicator for the operational performance of activated sludge processes and has a major influence on the development of filamentous bulking in activated sludge.This study focused on the impact of typical soluble and slowly-biodegradable organic compounds,investigating the pathways through which these substrates affect the occurrence of filamentous bulking in systems operated under both high-and low-oxygen conditions.Results showed that slowly-biodegradable organic compounds lead to a concentrated distribution of microorganisms within flocs,with inward growth of filamentous bacteria.Both Tween-80 and granular starch treated systems exhibited a significant increase in protein content.The glucose system,utilizing soluble substrates,exhibited a markedly higher total polysaccharide content.Microbial communities in the Tween-80 and granular starch treated systems were characterized by a higher abundance of bacteria known to enhance sludge flocculation and settling,such as Competibacter,Xanthomonadaceae and Zoogloea.These findings are of high significance for controlling the operational performance and stability of activated sludge systems,deepening our understanding and providing a novel perspective for the improvement of wastewater treatment processes. 展开更多
关键词 Sludge bulking Slowly biodegradable organic compounds Sludge morphology EPS Microbial community
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Clinical efficacy and mechanism of Bletilla striata and Chinese herbal compounds in treatment of peptic ulcer 被引量:2
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作者 Yi-Tong Sun Fang Zhou +1 位作者 Hong-Xin Zheng Jing-Dong Xiao 《World Journal of Gastroenterology》 2025年第30期23-32,共10页
Peptic ulcer(PU)is characterized by inflammation,necrosis,and erosion of the gastrointestinal mucosa caused by various pathogenic factors,leading to ulcer formation.The stomach and duodenum are the most commonly affec... Peptic ulcer(PU)is characterized by inflammation,necrosis,and erosion of the gastrointestinal mucosa caused by various pathogenic factors,leading to ulcer formation.The stomach and duodenum are the most commonly affected sites.Bletilla striata,a traditional Chinese medicinal herb,contains diverse chemical constituents and exhibits multiple pharmacological effects.As a key component in various traditional Chinese medicine compound formulations,it has demonstrated notable clinical efficacy.Moreover,it has a solid research foundation and broad application prospects in the treatment of gastrointestinal diseases.This paper systematically elaborates on the clinical efficacy and mechanisms of action of Bletilla striata in the treatment of PUs,drawing from ancient medical literature and traditional formula applications to provide support for clinical use. 展开更多
关键词 Bletilla striata Related traditional Chinese medicine compound formulations Peptic ulcer Mechanism of action Clinical efficacy
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Comprehensive characterization of volatile organic compounds in Chinese chemical industry park soils:Spatial variation,source identification,and health risk assessment 被引量:1
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作者 Haibao Zhu Yuanchen Chen +3 位作者 Zheng Ruan Han Wang Danhua Liu Meirong Zhao 《Journal of Environmental Sciences》 2025年第9期48-59,共12页
Ubiquitous contamination of the soil environment with volatile organic compounds(VOCs)has raised considerable concerns.However,there is still limited comprehensive surveying of soil VOCs on a national scale.Herein,65 ... Ubiquitous contamination of the soil environment with volatile organic compounds(VOCs)has raised considerable concerns.However,there is still limited comprehensive surveying of soil VOCs on a national scale.Herein,65 species of VOCswere simultaneously determined in surface soil samples collected from 63 chemical industrial parks(CIPs)across China.The results showed that the total VOC concentrations ranged from 7.15 to 1842 ng/g with a mean concentration of 326 ng/g(median:179 ng/g).Benzene homologs and halogenated hydrocarbons were identified as the dominant contaminant groups.Positive correlations between many VOC species indicated that these compounds probably originated from similar sources.Spatially,the hotspots of VOC pollution were located in eastern and southern China.Soils with higher clay content and a higher fraction of total organic carbon(TOC)content were significantly associated with higher soil VOC concentrations.Precipitation reduces the levels of highly water-soluble substances in surface soils.Both positive matrix factorization(PMF)and principal component analysis-multiple linear regression(PCA-MLR)identified a high proportion of industrial sources(PMF:59.2%and PCA-MLR:66.5%)and traffic emission sources(PMF:32.3%and PCA-MLR:33.5%).PMF,which had a higher R^(2) value(0.7892)than PCA-MLR(0.7683),was the preferred model for quantitative source analysis of soil VOCs.The health risk assessment indicated that the non-carcinogenic and carcinogenic risks of VOCs were at acceptable levels.Overall,this study provides valuable data on the occurrence of VOCs in soil from Chinese CIPs,which is essential for a comprehensive understanding of their environmental behavior. 展开更多
关键词 Volatile organic compounds Chemical industry park soils Source appointment Risk assessment
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Emission characteristics of biogenic volatile organic compounds in a subtropical pristine forest of southern China 被引量:2
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作者 Xi Chen Daocheng Gong +9 位作者 Youjing Lin Qiao Xu Yujin Wang Shiwei Liu Qinqin Li Fangyuan Ma Jiangyong Li Shuo Deng Hao Wang Boguang Wang 《Journal of Environmental Sciences》 2025年第2期665-682,共18页
Emission characteristics of biogenic volatile organic compounds(BVOCs)from dominant tree species in the subtropical pristine forests of China are extremely limited.Here we conducted in situ field measurements of BVOCs... Emission characteristics of biogenic volatile organic compounds(BVOCs)from dominant tree species in the subtropical pristine forests of China are extremely limited.Here we conducted in situ field measurements of BVOCs emissions from representative mature evergreen trees by using dynamic branch enclosures at four altitude gradients(600-1690ma.s.l.)in the Nanling Mountains of southern China.Composition characteristics as well as seasonal and altitudinal variations were analyzed.Standardized emission rates and canopyscale emission factors were then calculated.Results showed that BVOCs emission intensities in the wet season were generally higher than those in the dry season.Monoterpenes were the dominant BVOCs emitted from most broad-leaved trees,accounting for over 70%of the total.Schima superba,Yushania basihirsuta and Altingia chinensis had relatively high emission intensities and secondary pollutant formation potentials.The localized emission factors of isoprene were comparable to the defaults in the Model of Emissions of Gases and Aerosols fromNature(MEGAN),while emission factors of monoterpenes and sesquiterpenes were 2 to 58 times of those in the model.Our results can be used to update the current BVOCs emission inventory in MEGAN,thereby reducing the uncertainties of BVOCs emission estimations in forested regions of southern China. 展开更多
关键词 Biogenic volatile organic compounds(BVOCs) Dynamic enclosure system Nanling Mountains Emission factors Emission rates Chemical reactivity
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Evaluation of different solvents for phytochemical compounds,antioxidant activities,cholinesterase inhibition,and anti-HepG2 cell proliferation of three plant parts in Elaeagnus mollis 被引量:1
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作者 Hao Zhong Jingmiao Li +1 位作者 Changle Li Yulin Liu 《Journal of Chinese Pharmaceutical Sciences》 2025年第5期411-422,共12页
To explore the potential utilization of Elaeagnus mollis,we conducted a comprehensive assessment of its phytochemical composition,antioxidant properties,cholinesterase inhibition,and anti-HepG2 cell proliferation acti... To explore the potential utilization of Elaeagnus mollis,we conducted a comprehensive assessment of its phytochemical composition,antioxidant properties,cholinesterase inhibition,and anti-HepG2 cell proliferation activity across different plant parts(branch wood,branch bark,and pericarp)using various solvents(water,methanol,ethanol,and n-hexane).Our findings revealed that water extracts displayed superior antioxidant activities in ABTS and RP assays,while methanol extracts exhibited better performance in DPPH and FRAP assays.Moreover,methanol extracts demonstrated the highest effectiveness against anti-HepG2 cell proliferation,whereas n-hexane extracts showed greater efficiency in cholinesterase inhibition.Notably,branch bark extracts exhibited the highest levels of phytochemical compounds,with both branch bark and pericarp extracts demonstrating significant effects in cholinesterase inhibition and anti-HepG2 cell proliferation.Correlation analysis indicated that phytochemical compounds were primarily responsible for the observed biological activities.Overall,extracts from the branch bark and pericarp of E.mollis showed promising potential for antioxidant and anticancer activities,suggesting their suitability for applications in the pharmaceutical industry as health-promoting products. 展开更多
关键词 Elaeagnus mollis Phytochemical compounds Antioxidant activity Cholinesterase inhibitory Anti-HepG2 cell proliferation activities
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Exploring artificial intelligence approaches for predicting synergistic effects of active compounds in traditional Chinese medicine based on molecular compatibility theory 被引量:1
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作者 Yiwen Wang Tong Wu +5 位作者 Xingyu Li Qilan Xu Heshui Yu Shixin Cen Yi Wang Zheng Li 《Chinese Journal of Natural Medicines》 2025年第11期1409-1424,共16页
Due to its synergistic effects and reduced side effects,combination therapy has become an important strategy for treating complex diseases.In traditional Chinese medicine(TCM),the“monarch,minister,assistant,envoy”co... Due to its synergistic effects and reduced side effects,combination therapy has become an important strategy for treating complex diseases.In traditional Chinese medicine(TCM),the“monarch,minister,assistant,envoy”compatibilities theory provides a systematic framework for drug compatibility and has guided the formation of a large number of classic formulas.However,due to the complex compositions and diverse mechanisms of action of TCM,it is difficult to comprehensively reveal its potential synergistic patterns using traditional methods.Synergistic prediction based on molecular compatibility theory provides new ideas for identifying combinations of active compounds in TCM.Compared to resource-intensive traditional experimental methods,artificial intelligence possesses the ability to mine synergistic patterns from multi-omics and structural data,providing an efficient means for modeling and optimizing TCM combinations.This paper systematically reviews the application progress of AI in the synergistic prediction of TCM active compounds and explores the challenges and prospects of its application in modeling combination relationships,thereby contributing to the modernization of TCM theory and methodological innovation. 展开更多
关键词 Molecular compatibility theory Synergy prediction of TCM compounds Molecular drugs combination prediction Artificial intelligence
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N-Heterocyclic Carbene Catalyzed Esterification of Dicarbaldehydes with Arylboronic Acid for Axially Chiral Phosphorus Compounds
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作者 Huang Xuehui Lin Yanru +6 位作者 Li Zhaodi Zhang Yue Wang Xin Yuanyuan Gao Gong Xiaojie Li Fei Liu Lantao 《有机化学》 北大核心 2025年第10期3847-3855,共9页
Atropisomeric phosphines are crucial for asymmetric catalysis but remain synthetically challenging.Herein,an N-heterocyclic carbene(NHC)catalyzed esterification reaction of dialdehydes with arylboronic acids was devel... Atropisomeric phosphines are crucial for asymmetric catalysis but remain synthetically challenging.Herein,an N-heterocyclic carbene(NHC)catalyzed esterification reaction of dialdehydes with arylboronic acids was developed,successfully constructing the framework of axially chiral phosphorus compounds.Mechanistic studies have revealed that the reaction initially undergoes a desymmetrization process,followed by a kinetic resolution pathway,affording a series of axially chiral phosphorus compounds with high enantioselectivity(up to 92%ee). 展开更多
关键词 axially chiral phosphorus compounds N-heterocyclic carbene ESTERIFICATION DESYMMETRIZATION
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Visible-Light-Mediated O-H Functionalization Reactions of Alkenyl Alcohols with Diazo Compounds
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作者 Xie Haochi Qin Yongkang +6 位作者 Yang Ting Li Hujin Sun Jiajia Qian Mingcheng Zhao Shuai Hou Ya'nan Chen Xin 《有机化学》 北大核心 2025年第8期3004-3016,共13页
Visible-light-mediated O-H functionalization reactions of alcohols with diazo compounds have been fully developed in recent years.However,alkenyl and acetylenic alcohols were rarely examined in these reactions due to ... Visible-light-mediated O-H functionalization reactions of alcohols with diazo compounds have been fully developed in recent years.However,alkenyl and acetylenic alcohols were rarely examined in these reactions due to the inevitable side reactions involving cycloaddition.Herein,the visible-light-mediated O-H functionalization reactions of alkenyl alcohols with diazo compounds were developed.This process competed favorably with the cycloaddition reaction.A series of multifunctional ethers were provided in low to high yields with aryldiazoacetates or 3-diazooxindoles.Biologically relevant spirooxindole-fused oxacycle could be easily accessed from the O-H functionalization product of alkenyl alcohol and 3-diazooxindole. 展开更多
关键词 VISIBLE-LIGHT O-H functionalization alkenyl alcohol diazo compound spirooxindole-fused oxacycle
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