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Organic Chemistry Frontiers 2022年第3期9卷 781-787页

作者： Mu-Xue He Yan Yao Chun-Zhi Ai Zu-Yu Mo Yu-Zheng Wu Qi Zhou Ying-Ming Pan Hao-Tao Tang State Key Laboratory for Chemistry and Molecular Engineering of Medicinal Resources School of Chemistry and Pharmaceutical SciencesGuangxi Normal UniversityGuilin 541004China School of Public Health Guilin Medical UniversityGuilin 541004China Pharmacy School Guilin Medical UniversityGuilin 541004China Adesis Inc.A Universal Display company New CastleDelaware 19720USA

C-H functionalization of allenes is an available strategy to construct heterocyclic compounds.Herein we propose a sus-tainable electrocatalytic C-H activation for the synthesis of novel highly functionalized tetrasubs... 详细信息

关键词： compounds substituted furan

The short-chain perfluorinated compounds PFBS,PFHxS, PFBA and PFHxA, disrupt human mesenchymal stem cell self-renewal and adipogenic differentiation

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Journal of Environmental Sciences 2020年第2期32卷 187-199页

作者： Shuyu Liu Renjun Yang Nuoya Yin Francesco Faiola State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Resources and Environment University of Chinese Academy of SciencesBeijing 100049China Wellcome Trust/CRUK Gurdon Institute Department of PathologyUniversity of CambridgeCambridge CB21QNUK

Per-and polyfluorinated alkyl substances(PFASs) are commonly used in industrial processes and daily life products.Because they are persistent, they accumulate in the environment, wildlife and humans.Although many studies have focused on two of the most representative PFASs, PFOS and PFOA, the potential toxicity of short-chain PFASs has not yet been given sufficient attention.We used a battery of assays to evaluate the toxicity of several four-carbon and six-carbon perfluorinated sulfonates and carboxyl acids(PFBS,PFHxS, PFBA and PFHxA), with a human mesenchymal stem cell(hMSC) system.Our results demonstrate significant cyto-and potential developmental toxicity for all the compounds analyzed, with shared but also distinct mechanisms of toxicity.Moreover, the effects of PFBS and PFHxS were stronger than those of PFBA and PFHxA, but occurred at higher doses compared to PFOS or PFOA.

关键词： Short-chain perfluorinated compounds Human mesenchymal stem cells(hMSCs) Adipogenesis/osteogenesis Developmental toxicity PFBS/PFBA/PFHxS/PFHxA

The levels, sources and reactivity of volatile organic compounds in a typical urban area of Northeast China

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Journal of Environmental Sciences 2019年第5期31卷 121-134页

作者： Zhuobiao Ma Chengtang Liu Chenglong Zhang Pengfei Liu Can Ye Chaoyang Xue Di Zhao Jichen Sun Yiming Du Fahe Chai Yujing Mu Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences Center for Excellence in Regional Atmospheric Environment Institute of Urban Environment Chinese Academy of Sciences Shenyang Academy of Environmental Sciences Shenyang Environmental Monitoring Centre Chinese Research Academy of Environmental Sciences

Air concentrations of volatile organic compounds(VOCs) were continually measured at a monitoring site in Shenyang from 20 August to 16 September 2017. The average concentrations of alkanes, alkenes, aromatics and carbonyls were 28.54, 6.30, 5.59 and9.78 ppbv, respectively. Seven sources were identified by the Positive Matrix Factorization model based on the measurement data of VOCs and CO. Vehicle exhaust contributed the most(36.15%) to the total propene-equivalent concentration of the measured VOCs,followed by combustion emission(16.92%), vegetation emission and secondary formation(14.33%), solvent usage(10.59%), petrochemical industry emission(9.89%), petrol evaporation(6.28%), and liquefied petroleum gas(LPG) usage(5.84%). Vehicle exhaust, solvent usage and combustion emission were found to be the top three VOC sources for O_3 formation potential, accounting for 34.52%, 16.55% and 11.94%, respectively. The diurnal variation of the total VOCs from each source could be well explained by their emission characteristics,e.g., the two peaks of VOC concentrations from LPG usage were in line with the cooking times for breakfast and lunch. Wind rose plots of the VOCs from each source could reveal the possible distribution of the sources around the monitoring site. The O_3 pollution episodes during the measurement period were found to be coincident with the elevation of VOCs, which was mainly due to the air parcel from the southeast direction where petrochemical industry emission was found to be dominant, suggesting that the petrochemical industry emission from the southeast was probably a significant cause of O_3 pollution in Shenyang.

关键词： Volatile organic compounds Source apportionment Photochemical ozone formation Field measurement

Influence of physiological and environmental factors on the diurnal variation in emissions of biogenic volatile compounds from Pinus tabuliformis

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Journal of Environmental Sciences 2019年第7期31卷 102-118页

作者： Jungang Chen Huaxing Bi Xinxiao Yu Yanlin Fu Wenchao Liao College of Soil and Water Conservation Beijing Forestry University Institute of Ecology College of Urban and Environmental Sciences and Key Laboratory for Earth Surface Processes of the Ministry of Education Peking University Ji County Station Chinese National Ecosystem Research Network (CNERN) Key Laboratory of State Forestry Administration on Soil and Water Conservation Beijing Forestry University Beijing Engineering Research Center of Soil and Water Conservation Beijing Forestry University Engineering Research Center of Forestry Ecological Engineering Ministry of Education Beijing Forestry University Beijing Collaborative Innovation Center for Eco-Environmental Improvement With Forestry and Fruit Trees Beijing Water Consulting Co. LTD

Biological volatile organic compounds(BVOCs) have a large influence on atmospheric environmental quality, climate change and the carbon cycle. This study assesses the composition and diurnal variation in emission rates of BVOCs from Pinus tabuliformis, using an enclosure technique. Environmental parameters(temperature and light intensity) and physiological parameters(net photosynthetic rate, P_n; stomatal conductance, g_s; intercellular CO_2 concentration, C_i; and transpiration rate, T_r) that may affect emission behavior were continuously monitored. The 10 most abundant compound groups emitted by P. tabuliformis were classified by gas chromatography–mass spectrometry. The dominant monoterpenoid compounds emitted were α-pinene, β-myrcene, α-farnesene and limonene. The diurnal emission rate of BVOCs changed with temperature and light intensity, with dynamic analysis of BVOCs emissions revealing that their emission rates were more affected by temperature than light. The variation in monoterpene emission rates was consistent with estimates of P_n, g_s and T_r. Basal emission rates(at 30 °C,) of the main BVOCs ranged from 0.006 to 0.273 μg^(-1)/(hr g),while the basal ER standardization coefficients ranged from 0.049 to 0.144 °C^(-1). Overall, these results provide a detailed reference for the effective selection and configuration of tree species to effectively prevent and control atmospheric pollution.

关键词： Biogenic volatile organic compounds Pinus tabuliformis Emission rate Monoterpenes

Simultaneous quantification of fifty-one odor-causing compounds in drinking water using gas chromatography-triple quadrupole tandem mass spectrometry

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Journal of Environmental Sciences 2019年第5期31卷 100-110页

作者： Chunmiao Wang Jianwei Yu Qingyuan Guo Yu Zhao Nan Cao Zhiyong Yu Min Yang Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences University of Chinese Academy of Sciences College of Environmental Science & Engineering Yancheng Institute of Technology Beijing Waterworks Group

A wide range of compounds with various structural features can cause taste and odor(T&O)problems in drinking water. It would be desirable to determine all of these compounds using a simple analytical method. In this paper, a sensitive method combining liquid–liquid extraction(LLE) with gas chromatography-triple quadrupole tandem mass spectrometry(GC–MS/MS)was established to simultaneously analyze 51 odor-causing compounds in drinking water,including organic sulfides, aldehydes, benzenes, phenols, ethers, esters, ketones, nitrogenous heterocyclic compounds, 2-methylisoborneol and geosmin. Three deuterated analogs of target analytes, dimethyl disulfide-d6, benzaldehyde-d6 and o-cresol-3,4,5,6-d4,were used to correct the variations in recovery, and five isotope-labeled internal standards(4-chlorotoluene-d4, 1, 4-dichlorobenzene-d4, naphthalene-d8, acenaphthene-d10, phenanthrene-d10 respectively) were used prior to analysis to correct the variations arising from instrument fluctuations and injection errors. The calibration curves of the target compounds showed good linearity(R2> 0.99, level = 7),and method detection limits(MDLs) below 1/10 of the odor threshold concentrations were achieved for most of the odorants(0.10–20.55 ng/L). The average recoveries of most of the analytes in tap water samples were between 70% and 120%, and the method was reproducible(RSD compounds in water samples collected from three drinking water treatment plants(DWTPs) were analyzed by this method.According to the results, dimethyl trisulfide, dimethyl disulfide and indole were considered to be the key odorants responsible for the swampy/septic odor. 2-Methylisoborneol and geosmin were detected as the main odor-causing compounds for musty/earthy odor in DWTP B.

关键词： Odor-causing compounds Drinking water GC–MS/MS High-throughput detection

Emission of intermediate volatility organic compounds from a ship main engine burning heavy fuel oil

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Journal of Environmental Sciences 2019年第10期31卷 197-204页

作者： Haijun Lou Yuejiao Hao Weiwei Zhang Penghao Su Fan Zhang Yingjun Chen Daolun Feng Yifan Li College of Merchant Marine Shanghai Maritime University Shanghai 201306 China Department of Environmental Engineering Shanghai Maritime University Shanghai 201306 China College of Environmental Science and Engineering Tongji University Shanghai 200092 China International Joint Research Center for Persistent Toxic Substances(IJRC-PTS) Shanghai Maritime University Shanghai 200135 China International Joint Research Center for Persistent Toxic Substances(IJRC-PTS-NA) Toronto Ontario M2N 6X9 Canada

Intermediate volatility organic compounds(IVOCs)are crucial precursors of secondary organic aerosol(SOA).In this study,gaseous IVOCs emitted from a ship main engine burning heavy fuel oil(HFO)were investigated on a test bench,which could simulate the real-world operations and emissions of ocean-going ships.The chemical compositions,emission factors(EFs)and volatility distributions of IVOC emissions were investigated.The results showed that the main engine burning HFO emitted a large amount of IVOCs,with average IVOC EFs of 20.2-201 mg/kg-fuel.The IVOCs were mainly comprised of unspeciated compounds.The chemical compositions of exhaust IVOCs were different from that of HFO fuel,especially for polycyclic aromatic compounds and alkylcyclohexanes.The volatility distributions of IVOCs were also different between HFO exhausts and HFO fuel.The distinctions in IVOC emission characteristics between HFO exhausts and HFO fuel should be considered when assessing the IVOC emission and related SOA formation potentials from ocean-going ships burning HFO,especially when using fuel-surrogate models.

关键词： Marine main engine Intermediate-volatility organic compounds Heavy fuel oil Emission factor Chemical composition Distribution

Bioactive thionic compounds and aromatic glycosides from Ligusticum chuanxiong

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Acta Pharmaceutica Sinica B 2018年第5期8卷 818-824页

作者： Xu Zhang Bing Han Ziming Feng Jianshuang Jiang Yanan Yang Peicheng Zhang State Key Laboratory of Bioactive Substance and Function of Natural Medicines Institute of Materia Medica Peking Union Medical College and Chinese Academy of Medical Sciences

Three new thionic compounds,(S)-2-(2-carboxyl-2-hydroxyethylthio)-ferulic acid(1),(E)-2-methoxy-4-(3-(methylsulfonyl)prop-1-en-1-yl)phenol(2), and thiosenkyunolide C(3), together with two new aromatic glycosides(4 and 5) were isolated from the rhizome of Ligusticum chuanxiong Hort. Two known compounds(6 and 7) were also obtained. Their structures were elucidated based on extensive spectroscopic data(UV, IR, 1D and 2D NMR, and HR-ESI-MS). Furthermore the absolute configurations were established by comparison of their calculated and experimental circular dichroism spectra and by a dimolybdenum tetraacetate [Mo_2(AcO)_4]-induced circular dichroism procedure. All compounds were evaluated against lipopolysaccharide(LPS)-induced NO production in BV2 cells, and compounds 4 and 5 showed strong inhibitory activities with IC_(50) values of 2.03 and 3.09 μmol/L, respectively(positive control curcumin, IC_(50)=6.17 μmol/L). In addition, compound 1 showed weak proteintyrosine phosphatase-1 B(PTP1B) inhibitory activity.

关键词： Ligusticum chuanxiong Hort. Thionic compounds Aromatic glycosides Anti-inflammatory Natural products

Remarkably reducing carbon loss and H2 consumption on Ni–Ga intermetallic compounds in deoxygenation of methyl esters to hydrocarbons

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Journal of Energy Chemistry 2020年第2期29卷 194-208页

作者： Ning Zhao Ying Zheng Jixiang Chen Tianjin Key Laboratory of Applied Catalysis Science and Technology Department of Catalysis Science and EngineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjin 300350China

Ni–Ga alloy(Ni/Ga atomic ratio of 8),Ni3Ga and Ni5Ga3 intermetallic compounds(IMCs)catalysts were prepared from Ni–Mg-Al-Ga layered double hydroxides(LDHs)for the deoxygenation of methyl esters to hydrocarbons.In the alloy and IMCs,the presence of Ga reduced the surface Ni atom density,and the charge transfer from Ga to Ni increased the electron density of Ni.In the deoxygenation of methyl laurate,the Ni catalyst gave a complete hydrogenolysis of methyl laurate to CH4at 330°C and 3.0 MPa,while the presence of Ga promoted the HDO pathway and suppressed C–C bond hydrogenolysis and methanation.The Ni5Ga3 catalyst exhibited the best desired performance.Even at 400°C,it gave the yield of C11 and C12 hydrocarbons of ~99%,and the selectivity to CH4(SCH4) was only 2.4%.In the deoxygenation of methyl octanoate and methyl palmitate,the Ni5Ga3 catalyst also gave the yield of hydrocarbons above95%.Reactivity evaluation and methyl propionate-TPD and TPSR results indicate that the C–OCH3 bond instead of the O–CH3 one was cleaved on both Ni and bimetallic Ni–Ga catalysts.It is highlighted that methanol,derived from the C–OCH3 bond hydrogenolysis,mainly decomposed to CO and H2 on IMCs,while it was converted to methane on metallic Ni and alloy.It is of great significance that H2 could be yielded from the methyl ester itself.In short,the utilization of Ni–Ga IMCs can effectively reduce carbon loss and H2 consumption,all of which are ascribed to the geometric and electronic effects of Ga.

关键词： Ni–Ga intermetallic compounds Methyl ester Decarbonylation/decarboxylation Hydrodeoxygenation C–C bond hydrogenolysis Methanation

Surface/interface engineering of noble-metals and transition metal-based compounds for electrocatalytic applications

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Journal of Materials Science & Technology 2020年第3期38卷 221-236页

作者： Mengmeng Zhang Xiaopeng Li Jun Zhao Xiaopeng Han Cheng Zhong Wenbin Hu Yida Deng School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsKey Laboratory of Advanced Ceramics and Machining Technology(Ministry of Education)Tianjin UniversityTianjin 300072China Joint School of National University of Singapore and Tianjin University International Campus of Tianjin UniversityBinhai New CityFuzhou 350207China

Surface/interface engineering plays an important role in improving the performance and economizing the cost and usage of electrocatalysts.In recent years,substantial progress has been achieved in designing and developing highly active electrocatalysts with the deepening understanding of surface and interface enhanced mechanism.In this review,recent development about optimizing the surface and interfacial structure in promoting the electrocatalytic activity of noble-metals and transition metal compounds is presented and the chemical enhancements are also described in detail.The relationship between the surface/interface structures(both atomic and electronic configuration)and the electrochemical behaviors has been discussed.Finally,personal perspectives have been proposed,highlighting the challenges and opportunities for future development in tuning the surface/interface active sites of electrocatalysts.We believe that this timely review will be beneficial to the construction of highly active and durable electrode materials through optimizing surface atomic arrangement and interfacial interaction,which can largely promote the development of next-generation clean energy conversion technologies.

关键词： Surface/interface engineering Noble metals Transition metals compounds Electrocatalytic reactions

Advances in extraction and analysis of phenolic compounds from plant materials

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Chinese Journal of Natural Medicines 2017年第10期15卷 721-731页

作者： XU Cong-Cong WANG Bing PU Yi-Qiong TAO Jian-Sheng ZHANG Tong Experiment Ceiter of Teaching and Learning Shanghai University of Traditional Chinese Medicine Shanghai 201203 China School of Phar nacy Shanghai University of Traditional Chinese Medicine Shanghai 201203 China

Phenolic compounds,the most abundant secondary metabolites in plants,have received more and more attention in recent years because of their distinct bioactivities.This review summarizes different types of phenolic compounds and their extraction and analytical methods used in the recent reports,involving 59 phenolic compounds from 52 kinds of plants.The extraction methods include solid–liquid extraction,ultrasound-assisted extractions,microwave-assisted extractions,supercritical fluid extraction,and other methods.The analysis methods include spectrophotometry,gas chromatography,liquid chromatography,thin-layer chromatography,capillary electrophoresis,and near-infrared spectroscopy.After illustrating the specific conditions of the analytical methods,the advantages and disadvantages of each method are also summarized,pointing out their respective suitability.This review provides valuable reference for identification and/or quantification of phenolic compounds from natural products.

关键词： Phenolic compounds Flavonoid Extraction Quantification Liquid chromatography Gas chromatography