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C4-Methylation and C4-Methylation/Carbonyl Migration of Indoles via Steric Control
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作者 Xie Henan Cheng Yaohang An Guanghui 《有机化学》 北大核心 2026年第2期475-485,共11页
The development of methylation protocol has attracted intense attention owing to"magic methyl effect"in drug discovery.Meanwhile,the indole scaffold is prevalence in the natural products and pharmacophores.D... The development of methylation protocol has attracted intense attention owing to"magic methyl effect"in drug discovery.Meanwhile,the indole scaffold is prevalence in the natural products and pharmacophores.Despite the advances in other site selective methylation,there is scarce reports for C4 methylation of indoles and combination of a carbonyl group rearrangement with C—H methylation on indole ring.Herein,the C4 methylation of indoles and the steric controlled C4-methylation/carbonyl group migration are reported.The large steric hindrance at carbonyl group facilitates the carbonyl group migration,which provides a straightforward protocol for the synthesis of C2/C4 disubstituted indoles. 展开更多
关键词 METHYLATION carbonyl group dancing Pd catalysis magic methyl effect
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A Benchmark Study of Density Functional Theory(DFT)Methods for Mo-Catalyzed Carbonyl Oxidative Addition
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作者 Chen Zitong Wang Liwei +1 位作者 Shen Xiao Qi Xiaotian 《有机化学》 北大核心 2026年第2期507-514,共8页
In molybdenum chemistry,the oxidative addition of o-quinone or 1,2-dicarbonyl compounds to molybdenum has been widely used in Mo-catalyzed C—C bond construction.The carbonyl oxidative addition to Mo(0)or Mo(Ⅱ)is the... In molybdenum chemistry,the oxidative addition of o-quinone or 1,2-dicarbonyl compounds to molybdenum has been widely used in Mo-catalyzed C—C bond construction.The carbonyl oxidative addition to Mo(0)or Mo(Ⅱ)is the critical elementary reaction of molybdenum catalysis.However,the relevant density functional theory(DFT)studies are relatively scarce,especially regarding the rational selection of functionals.In this work,14 functionals were employed to investigate the Mo-catalyzed carbonyl oxidative addition step.A benchmark study was carried out to evaluate their performance in structure optimization and energy calculation.Analyses of mean absolute error(MAE)and mean squared error(MSE)indicated that the B3LYP-D3(BJ),TPSSh,and ωB97X-D functionals exhibited superior performance in structure optimization.Using the DLPNO-CCSD(T)functional as the reference,the M06,M06-L,and MN15-L functionals exhibited good performance for energy calculation based on the structures optimized using the B3LYP-D3(BJ)functional.In particular,MN15-L provided the best performance with the smallest MAE and MSE. 展开更多
关键词 molybdenum catalysis carbonyl oxidation addition density functional theory(DFT)calculation DFT benchmark study
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Enhancing C–N bond formation in amine carbonylation through dual hydrogen bonding catalysis under mild reaction conditions
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作者 Xiang Hui Jianhui Shi +4 位作者 Jiajun Zhang Yan Cao Huiquan Li Peng He Liguo Wang 《Green Energy & Environment》 2026年第1期236-247,共12页
The carbonylation of amines offers a promising route for synthesizing N-substituted carbamates with high atom economy.However,conventional catalysts exhibit limited catalytic efficiency,and the underlying proton trans... The carbonylation of amines offers a promising route for synthesizing N-substituted carbamates with high atom economy.However,conventional catalysts exhibit limited catalytic efficiency,and the underlying proton transfer mechanism remains elusive.Herein,we reported a metal-free,room-temperature strategy utilizing 1,5,7-triazabicyclo[4.4.0]dec-5-ene(TBD)as a dual hydrogen bond catalyst to synergistically activate propylamine(PA)and dimethyl carbonate(DMC).This green catalytic system achieves a 10-fold acceleration in reaction rate compared to other hydrogen bonding catalysts under mild conditions.This is enabled by dual hydrogen bonding of TBD with PA and DMC,which facilitates rapid proton transfer and stabilizes tetrahedral intermediates.Theoretical calculations confirm that the dual hydrogen bond system significantly lowers activation energy compared to single hydrogen bond analogs.Furthermore,it was revealed that the hydrogen bonding network within the product is the primary factor responsible for the sluggish reaction rate.This study demonstrates the effectiveness of a dual hydrogen bond system in accelerating the carbonylation of amines and provides a green route to access carbamates. 展开更多
关键词 Dual hydrogen bonds carbonylation reaction -C-N-bond Proton transfer Mild conditions
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Temporal variations and source analysis of ambient carbonyls in Hangzhou:A city-level study in the Yangtze River Delta region,China
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作者 Haonan Xu Xiaobing Pang +4 位作者 Danyun Chen Zhongjian Wei Yu Lu Huiyi Yang Lian Yu 《Journal of Environmental Sciences》 2026年第2期629-639,共11页
Carbonyls play an important role in the atmospheric chemistry as the main precursor for reactive radicals and peroxyacetyl nitrate.However,little research has been conducted so far on the seasonal variations of carbon... Carbonyls play an important role in the atmospheric chemistry as the main precursor for reactive radicals and peroxyacetyl nitrate.However,little research has been conducted so far on the seasonal variations of carbonyls in China’s urban atmosphere.In this study,ambient carbonyls were 24-hourly observed in four seasons in Hangzhou,a mega-city in the Yangtze River Delta Region,China.The concentration of total carbonyls was the highest in summer(44.35μg/m^(3)),the second in winter(44.05μg/m^(3)),the third in spring(29.31μg/m^(3))and autumn(27.11μg/m^(3)).The most abundant species were found to be acetone in spring,summer,and winter,while formaldehyde in autumn.Rainfall can significantly reduce the concentrations of most ambient carbonyls,with the largest decrease observed in the wet precipitation events occurring in spring and summer,while acetone concentrations remained invariable due to its lower water solubility.Multiple linear regression analysis and carbonyls ratios indicated that anthropogenic emissions were the predominant sources of carbonyls,and atmospheric formaldehyde was mainly emitted from primary sources other than secondary sources.Vehicular exhaust was identified as the primary source of ambient carbonyls,particularly in winter,and its contribution reached 92.80%to formaldehyde.Additionally,photochemical reactions were closely associated with the secondary production of formaldehyde in summer.Carbonyls showed strong ozone formation potential in all four seasons.Based on the health risk assessment,the exposure to ambient carbonyls is harmful to outdoor pedestrians.The results could provide essential information and references for simulating regional air quality and analyzing ozone pollution,which is essential for improving air quality in the Yangtze River Delta region. 展开更多
关键词 carbonylS Seasonal variations Wet deposition Source analysis Hangzhou
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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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A stable acyl cobalt-based catalyst with exceptionally elevated activity for the carbonylation of epoxides intoβ-lactones
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作者 Jianwei Jiang Vinothkumar Ganesan +3 位作者 Inrack Choi Jeongcheol Shin Sungho Yoon Kiyoung Park 《Chinese Journal of Catalysis》 2025年第1期336-344,共9页
Polyhydroxyalkanoate(PHA),a well-known biodegradable polymer,featuresβ-lactones as its monomers,which can be selectively synthesized through ring-expansion carbonylation of epoxides using well-defined[Lewis acid]^(+)... Polyhydroxyalkanoate(PHA),a well-known biodegradable polymer,featuresβ-lactones as its monomers,which can be selectively synthesized through ring-expansion carbonylation of epoxides using well-defined[Lewis acid]^(+)[Co(CO)_(4)]^(-)catalysts.However,the decomposition of[Co(CO)_(4)]^(-)species at temperatures exceeding 80℃presents a hurdle for the development of commercially viable processes under high-temperature reaction conditions to reduce reaction time.Drawing insights from stable{(acyl)Co(CO)n}intermediates involved in historical HCo(CO)_(4)-catalyzed hydroformylation processes,we sought to the high-temperature catalytic activity of epoxide ring-expansion carbonylation.The developed catalyst system,[(acetyl)Co(CO)_(2)dppp]and[(TPP)CrCl],exhibited exceptional catalytic performance with an unprecedented initial turnover frequency of 4700 h^(-1)at 100℃and a turnover numbers of 93000.Notably,the catalyst displayed outstanding stability,operating at 80℃for 168 h while selectively generatingβ-lactones. 展开更多
关键词 Epoxide carbonylation β-Lactone Cobalttetracarbonyl Acyl cobalt carbonyl High-temperature catalytic activity
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Recent Advances in Asymmetric Carbonylative Cross-Coupling Reactions
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作者 Su Lei Yang Xi +4 位作者 Yan Jie Jiang Yuanli Chen Lijuan Zheng Qingshu Liu Jiawang 《有机化学》 北大核心 2025年第6期2007-2047,共41页
Chiral carbonyl compounds frequently occur in natural products and pharmaceuticals. Additionally, they serve as important intermediates in organic synthesis. Transition metal-catalyzed asymmetric carbonylative cross-c... Chiral carbonyl compounds frequently occur in natural products and pharmaceuticals. Additionally, they serve as important intermediates in organic synthesis. Transition metal-catalyzed asymmetric carbonylative cross-coupling reactions are among the most straightforward and effective methods for synthesizing chiral carbonyl compounds, including esters, amides, and ketones. The advances in asymmetric carbonylative cross-coupling reactions using various O-, N-, C-, and S-containing nucleophiles or electrophiles over the past decade are summarized. 展开更多
关键词 carbonylATION transition-metal catalysis asymmetric catalysis carbon monoxide cross-coupling reaction
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Sustainable carbonylative transformation of alkyl iodides to amides via crosslinking of EDA and XAT
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作者 Hefei Yang Le-Cheng Wang Xiao-Feng Wu 《Chinese Chemical Letters》 2025年第9期318-322,共5页
The amide moiety plays an important role as a powerful bioactive backbone,and as the synthetic chemistry community moves toward more sp^(3)-rich scaffolds,alkyl halides have become the feedstock of choice for obtainin... The amide moiety plays an important role as a powerful bioactive backbone,and as the synthetic chemistry community moves toward more sp^(3)-rich scaffolds,alkyl halides have become the feedstock of choice for obtaining carbonylation products.With the development of photoredox catalysis,several aminocarbonylation systems for alkyl halides were developed which usually require transition metal catalysis.Considering the demands for green sustainable chemical synthesis,here we report a metal-free,exogenous catalyst-free aminocarbonylation reaction of alkyl iodides under atmospheric pressure of carbon monoxide.Through a combination of EDA and XAT strategies,the reaction occurs efficiently under only light irradiation at room temperature. 展开更多
关键词 carbonylATION AMIDE METAL-FREE Phtotchemistry RADICAL
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Carbonylative five-component synthesis of amides and esters withα-quaternary carbon center
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作者 Zhi-Peng Bao Hefei Yang +2 位作者 Ru-Han A Yuanrui Wang Xiao-Feng Wu 《Chinese Chemical Letters》 2025年第11期301-307,共7页
Carboxylic acid derivatives withα-quaternary carbon center are one of the most ubiquitous moieties in synthetic and medicinal chemistry.Hence,novel and efficient synthetic methods towards carboxylic acid derivatives ... Carboxylic acid derivatives withα-quaternary carbon center are one of the most ubiquitous moieties in synthetic and medicinal chemistry.Hence,novel and efficient synthetic methods towards carboxylic acid derivatives withα-quaternary carbon remain in high demand.However,most of the precursors of these complex compounds are not easy to prepare.Reported herein is a carbonylative five-component synthesis of amides and esters withα-quaternary carbon center enabled by palladium catalysis from abundant acrylonitrile,carbon monoxide,fluoroalkyl halides,and nucleophiles.Diverse amides and esters withα-quaternary carbon which contain difluoromethyl or perfluoroalkyl moiety were prepared in good to excellent yields,providing an efficient synthetic platform for sequential transformations. 展开更多
关键词 carbonylATION Palladium catalyst AMIDE ALKENE Multi component reaction
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Iron-promoted carbonylation–rearrangement ofα-aminoaryl-tethered alkylidenecyclopropanes with CO_(2):Facile synthesis of quinolinofurans
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作者 Zhen Zhang Xue-ling Chen +5 位作者 Xiu-Mei Xie Tian-Yu Gao Jing Qin Jun-Jie Li Chao Feng Da-Gang Yu 《Chinese Chemical Letters》 2025年第4期126-130,共5页
Herein,we report an iron-promoted carbonylation-rearrangement ofα-aminoaryl-tethered alkylidene cyclopropanes with CO_(2)to generate quinolinofuran derivatives.A variety of quinolinofuran derivatives are obtained in ... Herein,we report an iron-promoted carbonylation-rearrangement ofα-aminoaryl-tethered alkylidene cyclopropanes with CO_(2)to generate quinolinofuran derivatives.A variety of quinolinofuran derivatives are obtained in moderate to excellent yields,and two promising luminescent material molecules have been synthesized using the developed method.The Lewis acid Fe Cl_(3)was introduced into this reaction,which effectively promoted the ring opening and rearrangement of cyclopropanes.This reaction features a broad substrate scope,satisfactory functional group tolerance,facile scalability,and easy derivatization of the products. 展开更多
关键词 Carbon dioxide Quinolinofurans carbonylation–rearrangement IRON ALKYLIDENECYCLOPROPANES
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CO_(2)-H_(2)O co-electrolysis to CO/O_(2) for safe oxidative double carbonylation of ethylene/acetylene
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作者 Yanwei Cao Yunhao Qu +5 位作者 Bin Su Gongwei Wang Yang Huang Zhenmin Luo Lin Zhuang Lin He 《Chinese Journal of Catalysis》 2025年第7期202-210,共9页
Upgrading carbon dioxide(CO_(2))into value-added bulk chemicals offers a dual-benefit strategy for the carbon neutrality and circular carbon economy.Herein,we develop an integrated CO_(2) valorization strategy that sy... Upgrading carbon dioxide(CO_(2))into value-added bulk chemicals offers a dual-benefit strategy for the carbon neutrality and circular carbon economy.Herein,we develop an integrated CO_(2) valorization strategy that synergizes CO_(2)-H_(2)O co-electrolysis(producing CO/O_(2) feeds)with oxidative double carbonylation of ethylene/acetylene to synthesize CO_(2)-derived C_(4) diesters(dimethyl succinate,fumarate,and maleate).A group of versatile building blocks for manufacturing plasticizers,biodegradable polymers,and pharmaceutical intermediates.Remarkably,CO_(2) exhibits dual functionality:serving simultaneously as a CO/O_(2) source and an explosion suppressant during the oxidative carbonylation process.We systematically investigated the explosion-suppressing efficacy of CO_(2) in flammable gas mixtures(CO/O_(2),C_(2)H_(4)/CO/O_(2),and C_(2)H_(2)/CO/O_(2))across varying concentrations.Notably,the mixed gas stream from CO_(2)/H_(2)O co-electrolysis at an industrial-scale current densities of 400 mA/cm^(2),enabling direct utilization in oxidative double carbonylation reactions with exceptional compatibility and inherent safety.Extended applications were demonstrated through substrate scope expansion and gram-scale synthesis.This study establishes not only a safe protocol for oxidative carbonylation processes,but also opens an innovative pathway for sustainable CO_(2) valorization,including CO surrogate and explosion suppressant. 展开更多
关键词 Carbon dioxide ELECTROLYSIS Explosion suppressant Double carbonylation Explosion limits ETHYLENE ACETYLENE
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Copper-catalyzed carbonylative Suzuki-Miyaura coupling of un-activated alkyl bromides with aryl boronates
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作者 Jiajun Zhang Xiao-Feng Wu 《Chinese Journal of Catalysis》 2025年第6期146-152,共7页
Herein,we present a copper-catalyzed carbonylative cross-coupling of unactivated alkyl bromides with aryl boronates under CO atmosphere which enabling the efficient synthesis of C(sp3)-C(sp2)ketones with extensive fun... Herein,we present a copper-catalyzed carbonylative cross-coupling of unactivated alkyl bromides with aryl boronates under CO atmosphere which enabling the efficient synthesis of C(sp3)-C(sp2)ketones with extensive functional group compatibility.This strategy represents a significant advance in copper-catalyzed carbonylation involving alkyl bromides and C(sp2)-nucleophiles.The protocol addresses key challenges commonly encountered in the coupling of C(sp3)-alkyl halides with aryl boron reagents,such as sluggish oxidative addition of alkyl halides,competing Suzuki-Miyaura cross-coupling,undesired dehalogenation and so on.Distinguished by its broad substrate scope and high functional group tolerance,this approach offers a robust and versatile platform for the streamlined synthesis of alkyl aryl ketones. 展开更多
关键词 Copper catalysis Unactivated alkyl bromides carbonylATION Suzuki-Miyaura coupling Arylborons
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Provincial anthropogenic emission inventory of carbonyl sulfide(COS)in China from 2015 to 2021
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作者 JIANG Yunhao CHEN Bin +4 位作者 WANG Shaoqiang LI Tingyu CHEN Shiliang WANG Lunche WANG Lizhe 《Journal of Geographical Sciences》 2025年第5期923-940,共18页
Carbonyl sulfide(COS)is an effective tracer for estimating Gross Primary Productivity(GPP)in the carbon cycle.As the largest contribution to the atmosphere,anthropogenic COS emissions must be accurately quantified.In ... Carbonyl sulfide(COS)is an effective tracer for estimating Gross Primary Productivity(GPP)in the carbon cycle.As the largest contribution to the atmosphere,anthropogenic COS emissions must be accurately quantified.In this study,an anthropogenic COS emission inventory from 2015 to 2021 was constructed by applying the bottom-up approach based on activity data from emission sources.China’s anthropogenic COS emissions increased from approximately 171 to 198 Gg S yr^(-1)from 2015-2021,differing from the trends of other pollutants.Despite an initial decline in COS emissions across sectors during the early stage of the COVID-19 pandemic,a rapid rebound in emissions occurred following the resumption of economic activities.In 2021,industrial sources,coal combustion,agriculture and vehicle exhaust accounted for 76.8%,12.3%,10.5%and 0.4%of total COS emissions,respectively.The aluminum industry was the primary COS emitter among industrial sources,contributing40.7% of total emissions.Shandong,Shanxi,and Zhejiang were the top three provinces in terms of anthropogenic COS emissions,reaching 39,21 and 17 Gg S yr-1,respectively.Provincial-level regions(hereafter province)with high COS emissions are observed mainly in the eastern and coastal regions of China,which,together with the wind direction,helps explain the pattern of high COS concentrations in the Western Pacific Ocean in winter.The Green Contribution Coefficient of COS(GCCCOS)was used to assess the relationship between GDP and COS emissions,highlighting the disparity between GDP and COS contributions to green development.As part of this analysis,relevant recommendations are proposed to address this disparity.The COS emission inventory in our study can be used as input for the Sulfur Transport and Deposition Model(STEM),reducing uncertainties in the atmospheric COS source?sink budget and promoting understanding of the atmosphere sulfur cycle. 展开更多
关键词 anthropogenic emissions emission inventory carbonyl sulfide provincial scale
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Dimethoxymethane carbonylation and disproportionation over extra-large pore zeolite ZEO-1:Reaction network and mechanism
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作者 Shaolei Gao Peng Lu +6 位作者 Liang Qi Yingli Wang Hua Li Mao Ye Valentin Valtchev Alexis T.Bell Zhongmin Liu 《Chinese Journal of Catalysis》 2025年第1期230-245,共16页
Methyl methoxyacetate(MMAc)and methyl formate(MF)can be produced directly by heterogeneous zeolite-catalyzed carbonylation and disproportionation of dimethoxymethane(DMM),with near 100%selectivity for each process.Des... Methyl methoxyacetate(MMAc)and methyl formate(MF)can be produced directly by heterogeneous zeolite-catalyzed carbonylation and disproportionation of dimethoxymethane(DMM),with near 100%selectivity for each process.Despite continuous research efforts,the insight into the reaction mechanism and kinetics theory are still in their nascent stage.In this study,ZEO-1 material,a zeolite with up to now the largest cages comprising 16×16-MRs,16×12-MRs,and 12×12-MRs,was explored for DMM carbonylation and disproportionation reactions.The rate of MMAc formation based on accessible Brönsted acid sites is 2.5 times higher for ZEO-1(Si/Al=21)relative to the previously investigated FAU(Si/Al=15),indicating the positive effect of spatial separation of active sites in ZEO-1 on catalytic activity.A higher MF formation rate is also observed over ZEO-1 with lower activation energy(79.94 vs.95.19 kJ/mol)compared with FAU(Si/Al=30).Two types of active sites are proposed within ZEO-1 zeolite:Site 1 located in large cages formed by 16×16-MRs and 16×12-MRs,which is active predominantly for MMAc formation,and Site 2 located in smaller cages for methyl formate/dimethyl ether formation.Kinetics investigation of DMM carbonylation over ZEO-1 exhibit a first-order dependence on CO partial pressure and a slightly inverse-order dependence on DMM partial pressure.The DMM disproportionation is nearly first-order dependence on DMM partial pressure,while it reveals a strongly inverse dependence with increasing CO partial pressure.Furthermore,ZEO-1 exhibits good catalytic stability,and almost no deactivation is observed during the more than 70 h test with high carbonylation selectivity of above 89%,due to the well-enhanced diffusion property demonstrated by intelligent-gravimetric analysis. 展开更多
关键词 Dimethoxymethane carbonylation Dimethoxymethane disproportionation ZEOLITE In-situ IR Kinetic Reaction mechanism
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Parallel on-tissue chemical derivatization for enhanced molecular annotation of spatial carbonyl submetabolome
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作者 Shuai Guo Kening Li Bin Li 《Chinese Chemical Letters》 2025年第6期593-598,共6页
Matrix-assisted laser desorption/ionization(MALDI)mass spectrometry imaging(MSI)is an attractive technology for the visualization of metabolite distributions in tissues.However,detection and identification of low-abun... Matrix-assisted laser desorption/ionization(MALDI)mass spectrometry imaging(MSI)is an attractive technology for the visualization of metabolite distributions in tissues.However,detection and identification of low-abundance or poorly ionized metabolites remains challenging.Although on-tissue chemical derivatization(OTCD)holds great promise for improving MALDI MS detection sensitivity and selectivity by modification of specific chemical groups,the available methods for subsequent metabolite annotation are limited.Herein,a laser-assisted chemical transfer(LACT)-based parallel OTCD strategy was established for visualizing and annotating carbonyl metabolites in murine brain tissues.Girard's T and Girard's P reagents were applied for parallel OTCD to generate the characteristic m/z pairs with a 19.969 Da mass shift(±0.020 Da tolerance)for rapid recognition of derivatized metabolites.The similarity of spatial distribution patterns of each m/z pair was further statistically evaluated to remove the ambiguous annotations due to the occurrence of interference compounds.As a result,90 ion pairs were annotated as candidate carbonyl metabolites,66 were previously known and 24 were potential unreported carbonyls.Furthermore,the spatial alterations of carbonyl metabolites in the ischemic rat brain were successfully visualized and characterized,including small molecule aldehydes and ketones,long-chain fatty aldehydes,and monosaccharides.This further emphasizes great potential of parallel OTCD strategy for efficient and confident molecular annotation of spatial submetabolomics data associated with brain diseases. 展开更多
关键词 Mass spectrometry imaging On-tissue chemical derivatization Parallel derivatization carbonyl metabolites Mass-shift filtering Spatial distribution similarity
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Atmospheric chemistry of the coastal area is influenced by the convergence between the inland and marine air:Insight into carbonyl compounds
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作者 Jinhe Wang Ouyang Li +7 位作者 Pengcheng Zhang Xue Yang Ravi Yadav Shan Chen Yuhong Liu Chao Zhu Yangang Ren Abdelwahid Mellouki 《Journal of Environmental Sciences》 2025年第8期859-870,共12页
Marine biological activity has long been recognized to impact the atmospheric chemistry of coastal areas.In this work,we monitored the seasonal variation of carbonyl compounds in the coastal city of Qingdao,located in... Marine biological activity has long been recognized to impact the atmospheric chemistry of coastal areas.In this work,we monitored the seasonal variation of carbonyl compounds in the coastal city of Qingdao,located in the north of China’s coastline and the south of Jiaodong Peninsula,with the vast hinterland in the west.The mean total concentration of the 15 carbonyls varied significantly between seasons,with the highest observed in autumn(10.2±6.2 ppbv),followed by spring(9.0±3.0 ppbv),winter(6.4±4.0 ppbv)and summer(3.4±1.4 ppbv).Using bivariate analysis,the agricultural emissions from inland areas were responsible for the high levels of carbonyls in the autumn.In summer,clean and humid sea winds helped reduce the concentration of carbonyls,but they also brought air masses from vegetation,and marine organisms,which contributed to high levels of carbonyls in the spring of coastal areas.The observation-based chemistry box model found that the forma-tion of formaldehyde and acetaldehyde was primarily controlled by the RO+O2 reaction,and alkenes oxidation was the main contributing factor.Based on the OH radical loss rate(LOH)and ozone formation potential(OFP)calculation,we found that autumn and spring seasons have significantly higher values of LOH and OFP than winter and summer due to the presence of high concentrations of carbonyl compounds.Therefore,it is believed that these carbonyl compounds primarily originate from agricultural activities,and marine air influences the atmospheric chemistry of the coastal areas. 展开更多
关键词 Atmospheric chemistry Coastal area carbonyl compounds Inland agricultural activity Marine air mass
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Hydrogen Sulfide Alleviates Lipid Peroxidation-Mediated Carbonyl Stress in Uranium-Intoxicated Kidney Cells via Nrf2/ARE Signaling
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作者 Jialin Liu Min Wang +3 位作者 Rui Zhang Jifang Zheng Xixiu Jiang Qiaoni Hu 《Biomedical and Environmental Sciences》 2025年第4期484-500,共17页
Objective To explore the protective effects and underlying mechanisms of H_(2)S against lipid peroxidation-mediated carbonyl stress in the uranium-treated NRK-52E cells.Methods Cell viability was evaluated using CCK-8... Objective To explore the protective effects and underlying mechanisms of H_(2)S against lipid peroxidation-mediated carbonyl stress in the uranium-treated NRK-52E cells.Methods Cell viability was evaluated using CCK-8 assay. Apoptosis was measured using flow cytometry. Reagent kits were used to detect carbonyl stress markers malondialdehyde, 4-hydroxynonenal, thiobarbituric acid reactive substances, and protein carbonylation. Aldehyde-protein adduct formation and alcohol dehydrogenase, aldehyde dehydrogenase 2, aldo-keto reductase, nuclear factor E2-related factor 2(Nrf2), and cystathionine β-synthase(CBS) expression were determined using western blotting or real-time PCR. Sulforaphane(SFP) was used to activate Nrf2. RNA interference was used to inhibit CBS expression.Results GYY4137(an H_(2)S donor) pretreatment significantly reversed the uranium-induced increase in carbonyl stress markers and aldehyde-protein adducts. GYY4137 effectively restored the uraniumdecreased Nrf2 expression, nuclear translocation, and ratio of nuclear to cytoplasmic Nrf2, accompanied by a reversal of the uranium-decreased expression of CBS and aldehyde-metabolizing enzymes. The application of CBS siRNA efficiently abrogated the SFP-enhanced effects on the expression of CBS, Nrf2 activation, nuclear translocation, and ratio of nuclear to cytoplasmic Nrf2 and concomitantly reversed the SFP-enhanced effects of the uranium-induced mRNA expression of aldehyde-metabolizing enzymes.Simultaneously, CBS siRNA reversed the SFP-mediated alleviation of the uranium-induced increase in reactive aldehyde levels, apoptosis rates, and uranium-induced cell viability.Conclusion H_(2)S induces Nrf2 activation and nuclear translocation, which modulates the expression of aldehyde-metabolizing enzymes and the CBS/H_(2)S axis. Simultaneously, the Nrf2-controlled CBS/H_(2)S axis may at least partially promote Nrf2 activation and nuclear translocation. These events form a cycleregulating mode through which H_(2)S attenuates the carbonyl stress-mediated NRK-52E cytotoxicity triggered by uranium. 展开更多
关键词 Hydrogen sulfide(H_(2)S) carbonyl stress Lipid peroxidation URANIUM NEPHROTOXICITY NRF2
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Pilot-scale testing on catalytic hydrolysis of carbonyl sulfur combined with absorption-oxidation of H_(2)S for blast furnace gas purification
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作者 Yuting Lin Yuran Li +6 位作者 Bin Wang Jinglei Tian Hongqiang Liu Yiren Li Zhicheng Xu Qiang Cao Tingyu Zhu 《Journal of Environmental Sciences》 2025年第5期360-372,共13页
About 70%of the flue gas in the iron-steel industry has achieved multi-pollutant ultra-low emissions in China until 2023,and then the blast furnace gas purification has become the control step and bottleneck.Our resea... About 70%of the flue gas in the iron-steel industry has achieved multi-pollutant ultra-low emissions in China until 2023,and then the blast furnace gas purification has become the control step and bottleneck.Our research group has designed and constructed the world’s first blast furnace gas desulfurization pilot plant with the scale of 2000 Nm^(3)/h in October 2021.The pilot plant is a two-step combined desulfurization device including catalytic hydrolysis of carbonyl sulfur(COS)and absorption-oxidation of H_(2)S,continuously running for 120 days.In the hydrolysis system,one reason for catalyst deactivation has been verified from the sulfur deposition.HCN in blast furnace gas can be hydrolyzed on the hydrolysis catalyst to produce the nitrogen deposition,which is one of the reasons for catalyst deactivation and has never been found in previous studies.The deposition forms of S and N elements are determined,S element forms elemental sulfur and sulfate,while N element forms-NH_(2)and NH_(4)^(+).In the absorption-oxidation system,the O_(2)loading and the residence time have been optimized to control the oxidation of HS^(−)to produce elemental sulfur instead of by-product S_(2)O_(3)^(2−).The balance and distribution of S and N elements have been calculated for thewholemulti-phase system,approximately 84.4%of the sulfur is converted to solid sulfur product,about 1.3%of the sulfur and 19.2%of N element are deposited on the hydrolysis catalyst.The pilot plant provides technical support formulti-pollutant control of blast furnace. 展开更多
关键词 Blast furnace gas carbonyl sulfur Hydrogen sulfide Hydrogen cyanide Hydrolysis and oxidation Activated carbon
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Strain-enhanced liquid-metal-coated carbonyl-iron-powder-embedded polydi-methylsiloxane composites for effective electromagnetic wave absorption
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作者 Haeji Kim Philippe Tassin +1 位作者 Zungsun Choi Byungil Hwang 《International Journal of Minerals,Metallurgy and Materials》 2025年第7期1730-1738,共9页
The advancement of wireless technologies has increased the global demand for ubiquitous connectivity.However,this surge has increased electromagnetic pollution.This study introduces a composite comprising a polymer ma... The advancement of wireless technologies has increased the global demand for ubiquitous connectivity.However,this surge has increased electromagnetic pollution.This study introduces a composite comprising a polymer matrix(polydimethylsiloxane,PDMS)and a magnetic filler(carbonyl iron powder,CIP)to effectively absorb electromagnetic waves(EMW)and suppress electromagnetic noise,while exhibiting good mechanical properties.Eutectic gallium–indium(EGa In)liquid metal(LM)was introduced to improve the insulating properties of magnetic fillers.A core–shell structure was obtained by coating the CIP particles with EGa In,thereby combining magnetic and dielectric materials to enhance EMW absorption.The fluid characteristics of the LM improved the mechanical properties,whereas its electrical conductivity enhanced interfacial polarization loss,thereby augmenting the dielectric loss value of the composites.Moreover,the application of mechanical strain enhanced the EMW absorption of the LM/CIP/PDMS composites due to the formation of a conductive LM network. 展开更多
关键词 electromagnetic wave absorption strain enhancement liquid metal carbonyl iron powder particle core-shell structure dielectric loss
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