In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high effic...In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high efficiency under mild reaction conditions and show broad substrate scope by employing commercial available perfluoroalkyl sources, thus demonstrates high potent application in life and medicinal science.展开更多
A practical,metal-,and additive-free strategy for photo-and electro-induced perfluoroalkylation/cyclization of ohydroxyaryl enaminones with sodium perfluoroalkanesulfinates under mild conditions has been developed.Var...A practical,metal-,and additive-free strategy for photo-and electro-induced perfluoroalkylation/cyclization of ohydroxyaryl enaminones with sodium perfluoroalkanesulfinates under mild conditions has been developed.Various fluoroalkyl chromones were efficiently assembled in moderate to good yields.The scalability of this protocol and the assembling of diverse nitrogen-containing heterocycles from late-stage transformations of fluoroalkyl chromones greatly broaden the practical applications of this developed protocol.展开更多
Using Ce(SO4)2 or Mn(OAc)3 as oxidant, dibenzo crown ethers such as dibenzo-18-crown-6 (1) and dibenzo-24-crown-8 (5) and benzo-12-crown-4 (7) reacted smoothly with sodium perfluoroalkanesulfinates (2a-2e) to give the...Using Ce(SO4)2 or Mn(OAc)3 as oxidant, dibenzo crown ethers such as dibenzo-18-crown-6 (1) and dibenzo-24-crown-8 (5) and benzo-12-crown-4 (7) reacted smoothly with sodium perfluoroalkanesulfinates (2a-2e) to give the corresponding perfluoroalkylated products (3,4,6,7) in good yields with two isomers obtained in the case of dibenzo crown ethers. This provides a facile synthesis of perfluoroalkyl-containing crown ethers.展开更多
Several methods for the perfluoroalkylation of aromatics were reported.Both per- fluoroalkanesulfonyl bromide/BPO and perfluoroalkanesulfinate/oxidant systems were efficient reagents for the introduction of a pcrfluor...Several methods for the perfluoroalkylation of aromatics were reported.Both per- fluoroalkanesulfonyl bromide/BPO and perfluoroalkanesulfinate/oxidant systems were efficient reagents for the introduction of a pcrfluoroalkyl group onto various aromatic nuclei.In a two-phase solvent system with tetraalkylammonium salt as PTC,rcaction of perfluoroalkyl iodide and aromatics in the presence of sodium dithionitc gave perfluoroalkyl aromatics and/or addition-dimerization products.展开更多
Sodium perfluoroalkanesulfinates [R_fSO_2Na(1), Rf=CI(CF_2)_n; a, n=4; b, n=6; c, n=8] on oxidation with various single eletron oxidizing agents, such as Mn (OAc)_3·2H_2O and Ce (SO_4)_2, yielded perfluoroalkyl r...Sodium perfluoroalkanesulfinates [R_fSO_2Na(1), Rf=CI(CF_2)_n; a, n=4; b, n=6; c, n=8] on oxidation with various single eletron oxidizing agents, such as Mn (OAc)_3·2H_2O and Ce (SO_4)_2, yielded perfluoroalkyl radicals capable of perfluoroalkylating aromatic compounds to give a mixture of o-and p-monoperfluoroalkylated products. Thus, this reaction provides a new method for the synthesis of o-and p-monoperfluoroalkyl substituted aromatic compounds.展开更多
The application ot the sulfinatodehalogenation reaction system for the perfluoroalkylation of electron-rich aromatics is further studied.It was shown that perfluoroalkyl iodides reacted with polyhydric phenols,N,N-dia...The application ot the sulfinatodehalogenation reaction system for the perfluoroalkylation of electron-rich aromatics is further studied.It was shown that perfluoroalkyl iodides reacted with polyhydric phenols,N,N-dialkylanilines,2,5-dimethylpyrrole,N-methylpyrrole initiated by Na_2S_2O_4- NaHCO_3 gave the corresponding perfluoroalkylated products in moderate to good yields.展开更多
The reactions for introducing perfluoroalkyl groups into organic compounds have extensively studied.Most of these perfluoroalkylation reactions are realized by using thecommonly used perfluoroalkylating reagents RI,th...The reactions for introducing perfluoroalkyl groups into organic compounds have extensively studied.Most of these perfluoroalkylation reactions are realized by using thecommonly used perfluoroalkylating reagents RI,through addition to various olefins andacetylenes,initiated by means of photolysis,pyrolysis,free radical initiators and differentcatalysts,such as the main group metals,transition metals or their complexes in lower oxida-tion states,NaSOand Ph（OAc）, etc. Recently,perfluoroalkanesulfonyl halide was used to effect perfluoroalkylation,thusthe addition of perfluorosulfonyl chloride with olefin or acetylene was initiated by light orheat,and the perfluoroalkanesulfonyl bromides and iodides can effect the perfluoroalkylationthrough their spontaneous addition to some unsaturated compounds,and in other cases,through actinic,thermal or peroxide initiation.These reactions can be visionalized as展开更多
Perfluoroalkyl acid analogs(PFAAs)are a class of chemically stable environmentally persistent organic pollutants(POPs)that are difficult to degrade and have a strong capacity to accumulate in the human body.PFAAs have...Perfluoroalkyl acid analogs(PFAAs)are a class of chemically stable environmentally persistent organic pollutants(POPs)that are difficult to degrade and have a strong capacity to accumulate in the human body.PFAAs have been found to be biotoxic to humans and have been detected in various environmental media,especially in the cryosphere at trace concentrations.The cryosphere,sensitively responds to climate change,plays a crucial role in the global water,carbon and energy cycles.However,researches on cryosphere PFAAs especially in Tibetan Plateau(TP)is limited.Therefore,we summarize the physicochemical properties,physiological toxicity,spatiotemporal distribution,sources,diffusion and migration pathways,as well as analysis and removal methods of PFAAs in the cryosphere regions.The results show that PFAAs pollutants are mainly produced and distributed in the more economically developed countries in Europe and the United States,as well as in East Asia,and PFAAs can be transported by atmospheric circulation and water cycle to remote regions including cryosphere regions.The current detection methods for PFAAs in cryosphere need to be further refined for increased accuracy and convenience.There is also a need to develop more effective removal methods that will reduce the environmental and human threats posed by these PFAAs.Finally,we propose key scientific questions for future research in cryosphere including PFAAs redistribution influenced by cryosphere changes,human activities,and the interaction of other spheres.展开更多
Perfluoroalkyl and polyfluoroalkyl substances(PFASs)pollution with their toxicity,carcinogenicity,and persistence has been concerned worldwide.Research into novel materials for detecting and removing PFASs has increas...Perfluoroalkyl and polyfluoroalkyl substances(PFASs)pollution with their toxicity,carcinogenicity,and persistence has been concerned worldwide.Research into novel materials for detecting and removing PFASs has increased rapidly,particularly in regard to the emergence of well-characterized single-atom materials(SAMs).Owing to the high selectivity,high atom utilization,and abundant active sites of SAMs,these materials exhibit remarkable efficacy in the detection and removal of PFASs.In this work,recent advances in the synthesis of SAMs for the detection and removal PFASs are reviewed.In-depth discussions of the structure-activity relationship and reaction mechanisms have demonstrated the high efficiency,activity,and selectivity of SAMs for the detection,adsorption,and degradation of PFASs.To optimize the application of SAMs in PFASs remediation,this review comprehensively surveys SAMs applications for PFASs and analyzes potential design strategies based on synthesis methods and corresponding properties.Synthesis strategies such as wet-chemistry,which offer ease of operation and high potential for large-scale production,are recommended for the further exploration of specific SAMs for the detection and removal of PFASs.Finally,this review identifies the challenges and opportunities for development of SAMs for the detection and remediation of PFASs,providing an outlook on strategic goals for a green economy and sustainable development.展开更多
[Objectives]To extract and purify perfluoroalkyl and polyfluoroalkyl substances(PFAS)from aquatic products and determine the optimal pretreatment conditions.[Methods]The QuEChERS method was employed for the extraction...[Objectives]To extract and purify perfluoroalkyl and polyfluoroalkyl substances(PFAS)from aquatic products and determine the optimal pretreatment conditions.[Methods]The QuEChERS method was employed for the extraction and purification of PFAS in aquatic products.The detection of PFAS was carried out using liquid chromatography-tandem mass spectrometry(LC-MS/MS)in ESI negative ion mode with multiple reaction monitoring(MRM),and quantification was performed using the external standard method.By optimizing instrument parameters such as ion source temperature,spray voltage,and collision energy,high selectivity and sensitivity of the detection were ensured.[Results]The established calibration curves for 28 PFAS compounds compounds,covering a range of 0.02 to 20 ng/mL,demonstrated excellent linearity.Spike recovery tests yielded limits of detection(LOD)between 0.02 and 0.5μg/kg for the 28 PFAS compounds compounds,with recovery rates ranging from 72.2%to 113.0%.[Conclusions]The method established in this study demonstrates excellent linearity,and is accurate,reliable,efficient,simple,and rapid.It possesses considerable practical applicability and can be used for the quality and risk assessment of 28 PFAS compounds compounds in aquatic products,indicating high practical utility.展开更多
In this article, the synthesis and characterization of a novel fluoromonomer and its copolymer with acrylamide is reported. 2-perfluoroamyl-4-hydroxylquinoline 2 was synthesized from ethyl 2, 2-dihydroperfluoroheptano...In this article, the synthesis and characterization of a novel fluoromonomer and its copolymer with acrylamide is reported. 2-perfluoroamyl-4-hydroxylquinoline 2 was synthesized from ethyl 2, 2-dihydroperfluoroheptanoate in high yields. The monomer 4 was then synthesized from 2 in two steps readily in high yields. Synthesis and characterization of copolymers of acrylamide (AM) and the fluoromonomer were investigated. The composition and intrinsic viscosity of these copolymers were studied. It was found that the rheological properties of aqueous solutions of polyacrylamide were modified significantly when a small proportion of the fluoromonomer 4 was incorporated on investigating the viscosity-concentration profiles, pseudoplasticity of these solutions and the effect of the presence of surfactant. These results could be explained by the hydrophobic association of the fluorocarbon segments in the aqueous solutions of these copolymers.展开更多
The purpose of this study was to determine perfluoroalkyl substances（PFASs） in human serum, urine, hair and nail from general populations, and to investigate the possibility for human urine, hair and nail used as th...The purpose of this study was to determine perfluoroalkyl substances（PFASs） in human serum, urine, hair and nail from general populations, and to investigate the possibility for human urine, hair and nail used as the biomonitoring sample for PFASs exposure. We detected the concentrations of PFHx A, PFOA, PFNA, PFDA, PFUn DA, PFDo A, PFHx S and PFOS in 39 matched human serum, urine, hair and nail samples from Shenzhen in China. The detection frequency and the median level of PFOS were all higher than that of the other PFASs in four matrices. The median concentration of PFOS in serum, urine, hair, and nail were 9.24 ng/mL, 13.96 ng/L, 0.58 ng/g and 0.63 ng/g, respectively. The results of spearman correlation test indicated that nail was an ideal matrix for biomonitoring PFOS rather than human urine and hair in general populations for the non-invasive sampling.展开更多
This study was conducted to examine the association of perfluoroalkyl substance（PFAS）exposure with gestational diabetes mellitus（GDM） risk and postpartum fasting blood glucose.We used a 1：2 matched case–control ...This study was conducted to examine the association of perfluoroalkyl substance（PFAS）exposure with gestational diabetes mellitus（GDM） risk and postpartum fasting blood glucose.We used a 1：2 matched case–control study with 84 GDM subjects and 168 healthy pregnant women from Beijing, China. The maternal blood was collected at 1–2 days before delivery, and eight linear isomers and fourteen branched isomers were determined in maternal serum.Logistic regression analyses were performed to evaluate the associations after adjusting for potential confounders. The median of the sum of levels of total PFASs was 4.24 ng/m L with a interquartile range（IQR） of 2.82–6.54 ng/m L. Although maternal PFAS exposure was not associated with risk of GDM, significant positive associations were observed between evaluated exposure to specific PFAS congeners and increasing blood glucose. The odds ratio（ORs） of the highest category of postpartum fasting blood glucose for perfluoro-1-metylheptylsulfonat（1 m-PFOS）, perfluoro-3/4-metylheptylsulfonat（3 m＋4 m-PFOS）, perfluoro-5-metylheptylsulfonat（5 m-PFOS）, and perfluorohexane sulfonate（PFHx S） were 2.03（95% CI： 1.09–3.77）, 1.93（95% CI：1.04–3.58）, 2.48（95% CI： 1.33–4.65）, and 2.26（95% CI： 1.21–4.21）, respectively, suggesting negative effects of maternal exposure to specific PFAS compounds on glucose metabolism.展开更多
The levels of six perfluoroalkyl substances（PFASs） in surface sediment and their vertical variations in dated sediment cores from the Haihe River were investigated; studied substances included perfluorooctanoic acid...The levels of six perfluoroalkyl substances（PFASs） in surface sediment and their vertical variations in dated sediment cores from the Haihe River were investigated; studied substances included perfluorooctanoic acid（PFOA）,perfluorononanoic acid（PFNA）,perfluorooctane sulfonate（PFOS）,perfluorodecanoic acid（PFDA）,perfluoroundecanoic acid（PFUnA）,and perfluorododecanoic acid（PFDoA）. Results showed that the total PFAS concentration in surface sediment ranged between 0.52 and 16.33 ng/g dry weight（dw） with an average of3.47 ng/g dw,with PFOS and PFOA as the dominant PFASs. In general,the PFAS concentrations in the mainstream increased from the upper to the lower reaches,except that a drop occurred downstream of the Erdao dam. Although the PFASs in the sediment cores did not show a clear decreasing or increasing trend with depth,the three cores had a similar vertical variation.The PFAS levels were relatively low in the surface sediment,and reached the first high point at8–20 cm as a result of the wide use of PFASs from 1990 to 2000. After that the PFAS levels decreased,and then increased to a second high point at about 40–48 cm,which might be caused by the leaching of PFASs in sediment. Because PFASs have hydrophilic groups and relatively high solubility,the PFASs will transfer from the upper to lower layers of sediment when water infiltration occurs,leading to the fluctuation of PFAS levels in sediment cores. This study suggests that both the temporal variation of sources and transfer processes of PFASs in sediments are important factors influencing the vertical variation of PFASs in sediment cores.展开更多
It is extremely important to analyze the contaminative behaviors of Perfluoroalkyl acids(PFAAs) due to their serious threats to urban environments which are closely related to humans. Current study aimed to explore th...It is extremely important to analyze the contaminative behaviors of Perfluoroalkyl acids(PFAAs) due to their serious threats to urban environments which are closely related to humans. Current study aimed to explore the distribution, source apportionment and ecological risk assessment of PFAAs in surface water from Shijiazhuang, China. The concentrations of ΣPFAAs ranged from 19.5 to 125.9 ng/L in the investigation area. Perfluorobutanesulfonic acid(PFBS) and perfluoropentanoic acid(PFPeA) were the predominant contaminants(mean value: 14.3 ng/L and 16.6 ng/L, respectively). The distribution of PFAAs according to geospatial analysis and hierarchical clustering analysis(HCA) showed that higher levels of ΣPFAAs were detected in the southern surface water of Shijiazhuang and there was a stepwise decrease from the wet season to the dry season. Furthermore, based on source apportionment,the dominant potential sources were found to be wastewater treatment plant(WWTP) effluents and industrial discharge. The risk quotients(RQs) revealed low ecological risks of all PFAAs for aquatic organisms in Shijiazhuang surface water. Collectively, this study provided basic data for regulatory strategies for controlling PFAA pollutions in urban surface water.展开更多
Imagine if a group of toxic substances that increase oxidative stress and disrupt glucose and lipid metabolism have been broadly used worldwide for applications such as repellent,food packaging,and non-stick frying pa...Imagine if a group of toxic substances that increase oxidative stress and disrupt glucose and lipid metabolism have been broadly used worldwide for applications such as repellent,food packaging,and non-stick frying pan coatings.Now imagine if some of these substances have half-lives as long as 3-8 years.展开更多
Many per-and polyfluoralkyl substances(PFASs)may disrupt maternal thyroid hormone homeostasis in pregnancy.Concerns should be raised regarding the PFASs exposure in pregnant women because thyroid hormones are involved...Many per-and polyfluoralkyl substances(PFASs)may disrupt maternal thyroid hormone homeostasis in pregnancy.Concerns should be raised regarding the PFASs exposure in pregnant women because thyroid hormones are involved in the early development of the fetus.In this study,we measured the concentrations of 13 PFASs,including five novel shortchain PFASs,in serum from 123 pregnant women in Beijing,China.Linear regression models were used to investigate the association between thyroid-stimulating hormone(TSH)or free thyroxine(FT4)levels and PFASs concentrations under consideration of the impacts of pregnancy-induced physiological factors.We found that perfluorobutanoic acid(PFBA)(β=0.189,95%CI=-0.039,0.417,p=0.10)and perfluorodecanoic acid(PFDA)(β=-0.554,95%CI=-1.16,0.049,p=0.071)were suggestive of significant association with TSH in thyroid peroxidase antibody(TPOAb)negative women.No association was observed between all PFASs and FT4 levels after controlling for these confounding factors,such as BMI,gestational weight gain and maternal age.These findings suggest that it should pay more attention to the association between thyroid hormone levels and short-chain PFASs concentrations.Future studies could consider a greater sample and the inclusion of other clinical indicators of thyroid function,such as free T3 and total T3.展开更多
Receptor models have been proved as useful tools to identify source categories and quantitatively calculate the contributions of extracted sources.In this study,sixty surface sediment samples were collected from fourt...Receptor models have been proved as useful tools to identify source categories and quantitatively calculate the contributions of extracted sources.In this study,sixty surface sediment samples were collected from fourteen lakes in Jiangsu Province,China.The total concentrations of C_4–C_（14）-perfluoroalkyl carboxylic acids and perfluorooctane sulfonic acid（∑_（12）PFASs） in sediments ranged from 0.264 to 4.44 ng/g dw（dry weight）,with an average of 1.76 ng/g dw.Three commonly-applied receptor models,namely principal component analysis-multiple linear regression（PCA-MLR）,positive matrix factorization（PMF） and Unmix models,were employed to apportion PFAS sources in sediments.Overall,these three models all could well track the ∑_（12） PFASs concentrations as well as the concentrations explained in sediments.These three models identified consistently four PFAS sources：the textile treatment sources,the fluoropolymer processing aid/fluororesin coating sources,the textile treatment/metal plating sources and the precious metal sources,contributing 28.1%,37.0%,29.7% and 5.3% by PCA-MLR model,30.60%,39.3%,22.4% and 7.7% by PMF model,and 20.6%,52.4%,20.2% and 6.8% by Unmix model to the ∑_（12） PFASs,respectively.Comparative statistics of multiple analytical methods could minimize individual-method weaknesses and provide convergent results to enhance the persuasiveness of the conclusions.The findings could give us a better knowledge of PFAS sources in aquatic environments.展开更多
This study examined concentrations of 15 perfluoroalkyl acids（PFAAs） in tissues from male Mozambique tilapia（Oreochromis mossambicus） collected at Loskop Dam, Mpumalanga,South Africa in 2014 and 2016. Nine of the ...This study examined concentrations of 15 perfluoroalkyl acids（PFAAs） in tissues from male Mozambique tilapia（Oreochromis mossambicus） collected at Loskop Dam, Mpumalanga,South Africa in 2014 and 2016. Nine of the 15 PFAAs were detected frequently and were included in statistical analysis and included two of the most commonly known PFAAs,perfluorooctanesulfonic acid（PFOS）（median, 41.6 ng/g） and perfluorooctanoic acid（PFOA）（median, 0.0825 ng/g）. Of the tissues measured, plasma（2016 and 2014 median, 22.2 ng/g）contained the highest PFAA burden followed by（in descending order）： liver（median,11.6 ng/g）, kidney（median, 9.04 ng/g）, spleen（median, 5.92 ng/g）, adipose（median, 2.54 ng/g）, and muscle（median, 1.11 ng/g）. Loskop Dam tilapia have been affected by an inflammatory disease of the adipose tissue known as pansteatitis, so this study also aimed to investigate relationships between PFAA tissue concentrations and incidence of pansteatitis or fish health status. Results revealed that healthy tilapia exhibited an overall higher（p-value 〈 0.05） PFAA burden than pansteatitis-affected tilapia across all tissues.Further analysis showed that organs previously noted in the literature to contain the highest PFAA concentrations, such as kidney, liver, and plasma, were the organs driving the difference in PFAA burden between the two tilapia groups. Care must be taken in the interpretations we draw from not only the results of our study, but also other PFAA measurements made on populations（human and wildlife alike） under differing health status.展开更多
An on-line solid phase extraction-high performance liquid chromatography-tandem mass spectrometry method for the analysis of perfluoroalkyl substances（PFASs） in water samples was developed.The optimal analytical con...An on-line solid phase extraction-high performance liquid chromatography-tandem mass spectrometry method for the analysis of perfluoroalkyl substances（PFASs） in water samples was developed.The optimal analytical conditions were obtained through the optimization of the extraction efficiency of online solid phase extraction column,sample loading rate and loading volume,and the concentration of ammonium acetate in mobile phase.Under the optimal condition,the analytical method displayed good linearity（r^2〉0.99） for 12 PFASs（C5-C14 perfluoroalkyl carboxylic acids and C6/C8 perfluoroalkyl sulfonic acids） over a concentration range of 0.5-100 ng/L.The limits of quantitation for samples were between 0.025 ng/L and 0.5 ng/L and the relative standard deviations（RSD） of five consecutive analyses were less than 10%for 1 ng/L standard solution.Satisfactory results were obtained using this analytical method for the analysis of perfluoroalkyl substances in Antarctic ice core samples.The recoveries of all perfluoroalkyl substances were in a range of 73%-117%when the samples were spiked with standards at the concentrations of 2.5 ng/L and 25 ng/L.展开更多
基金financially supported by the Young Talents Cultivation Program of the China Association for Science and Technology(No.2015-41)The Training Programme Foundation for the Talents of the Zun Yi Science and Technology Bureau(No.201540)+1 种基金Key Programs of Guizhou Province(125 Program,No.2015039)The Natural Science Foundation of Jiangsu Province(No.BK20141265)
文摘In this work, an efficient and facile method for the preparation of 5-perfluoroalkylation uracils and uracil nucleosides through visible-light-mediated reaction has been developed. The reaction processes in high efficiency under mild reaction conditions and show broad substrate scope by employing commercial available perfluoroalkyl sources, thus demonstrates high potent application in life and medicinal science.
基金the National Natural Science Foundation of China(No.22178314 and 21776254)the Zhejiang Provincial Key R&D Project(No.2021C03148)the Opening Project of Zhejiang Engineering Research Center of Fat-soluble Vitamin(2023)for financial help(No.202306).
文摘A practical,metal-,and additive-free strategy for photo-and electro-induced perfluoroalkylation/cyclization of ohydroxyaryl enaminones with sodium perfluoroalkanesulfinates under mild conditions has been developed.Various fluoroalkyl chromones were efficiently assembled in moderate to good yields.The scalability of this protocol and the assembling of diverse nitrogen-containing heterocycles from late-stage transformations of fluoroalkyl chromones greatly broaden the practical applications of this developed protocol.
文摘Using Ce(SO4)2 or Mn(OAc)3 as oxidant, dibenzo crown ethers such as dibenzo-18-crown-6 (1) and dibenzo-24-crown-8 (5) and benzo-12-crown-4 (7) reacted smoothly with sodium perfluoroalkanesulfinates (2a-2e) to give the corresponding perfluoroalkylated products (3,4,6,7) in good yields with two isomers obtained in the case of dibenzo crown ethers. This provides a facile synthesis of perfluoroalkyl-containing crown ethers.
文摘Several methods for the perfluoroalkylation of aromatics were reported.Both per- fluoroalkanesulfonyl bromide/BPO and perfluoroalkanesulfinate/oxidant systems were efficient reagents for the introduction of a pcrfluoroalkyl group onto various aromatic nuclei.In a two-phase solvent system with tetraalkylammonium salt as PTC,rcaction of perfluoroalkyl iodide and aromatics in the presence of sodium dithionitc gave perfluoroalkyl aromatics and/or addition-dimerization products.
文摘Sodium perfluoroalkanesulfinates [R_fSO_2Na(1), Rf=CI(CF_2)_n; a, n=4; b, n=6; c, n=8] on oxidation with various single eletron oxidizing agents, such as Mn (OAc)_3·2H_2O and Ce (SO_4)_2, yielded perfluoroalkyl radicals capable of perfluoroalkylating aromatic compounds to give a mixture of o-and p-monoperfluoroalkylated products. Thus, this reaction provides a new method for the synthesis of o-and p-monoperfluoroalkyl substituted aromatic compounds.
基金the National Natural Science Foundation of China.Part ⅩⅩⅢ in this series,see Huang,W.-Y.Zhuang,J.-L.,Chinese J.Chem.,9,270 (1991).
文摘The application ot the sulfinatodehalogenation reaction system for the perfluoroalkylation of electron-rich aromatics is further studied.It was shown that perfluoroalkyl iodides reacted with polyhydric phenols,N,N-dialkylanilines,2,5-dimethylpyrrole,N-methylpyrrole initiated by Na_2S_2O_4- NaHCO_3 gave the corresponding perfluoroalkylated products in moderate to good yields.
文摘The reactions for introducing perfluoroalkyl groups into organic compounds have extensively studied.Most of these perfluoroalkylation reactions are realized by using thecommonly used perfluoroalkylating reagents RI,through addition to various olefins andacetylenes,initiated by means of photolysis,pyrolysis,free radical initiators and differentcatalysts,such as the main group metals,transition metals or their complexes in lower oxida-tion states,NaSOand Ph（OAc）, etc. Recently,perfluoroalkanesulfonyl halide was used to effect perfluoroalkylation,thusthe addition of perfluorosulfonyl chloride with olefin or acetylene was initiated by light orheat,and the perfluoroalkanesulfonyl bromides and iodides can effect the perfluoroalkylationthrough their spontaneous addition to some unsaturated compounds,and in other cases,through actinic,thermal or peroxide initiation.These reactions can be visionalized as
基金supported by the Gansu Provincial Science and Technology Program(22ZD6FA005)West Light Foundation of The Chinese Academy of Sciences(xbzg-zdsys-202306)+2 种基金Science Fund for Creative Research Groups of Gansu Province(Grant No.23JRRA567)Taishan Scholars Program of Shandong Province(No.tsqn202312158)Key Research and Development Program of Gansu Province(22YF7FA041)。
文摘Perfluoroalkyl acid analogs(PFAAs)are a class of chemically stable environmentally persistent organic pollutants(POPs)that are difficult to degrade and have a strong capacity to accumulate in the human body.PFAAs have been found to be biotoxic to humans and have been detected in various environmental media,especially in the cryosphere at trace concentrations.The cryosphere,sensitively responds to climate change,plays a crucial role in the global water,carbon and energy cycles.However,researches on cryosphere PFAAs especially in Tibetan Plateau(TP)is limited.Therefore,we summarize the physicochemical properties,physiological toxicity,spatiotemporal distribution,sources,diffusion and migration pathways,as well as analysis and removal methods of PFAAs in the cryosphere regions.The results show that PFAAs pollutants are mainly produced and distributed in the more economically developed countries in Europe and the United States,as well as in East Asia,and PFAAs can be transported by atmospheric circulation and water cycle to remote regions including cryosphere regions.The current detection methods for PFAAs in cryosphere need to be further refined for increased accuracy and convenience.There is also a need to develop more effective removal methods that will reduce the environmental and human threats posed by these PFAAs.Finally,we propose key scientific questions for future research in cryosphere including PFAAs redistribution influenced by cryosphere changes,human activities,and the interaction of other spheres.
基金supported by Shenzhen Science and Technology Program(NO.JCYJ20210324094000001).
文摘Perfluoroalkyl and polyfluoroalkyl substances(PFASs)pollution with their toxicity,carcinogenicity,and persistence has been concerned worldwide.Research into novel materials for detecting and removing PFASs has increased rapidly,particularly in regard to the emergence of well-characterized single-atom materials(SAMs).Owing to the high selectivity,high atom utilization,and abundant active sites of SAMs,these materials exhibit remarkable efficacy in the detection and removal of PFASs.In this work,recent advances in the synthesis of SAMs for the detection and removal PFASs are reviewed.In-depth discussions of the structure-activity relationship and reaction mechanisms have demonstrated the high efficiency,activity,and selectivity of SAMs for the detection,adsorption,and degradation of PFASs.To optimize the application of SAMs in PFASs remediation,this review comprehensively surveys SAMs applications for PFASs and analyzes potential design strategies based on synthesis methods and corresponding properties.Synthesis strategies such as wet-chemistry,which offer ease of operation and high potential for large-scale production,are recommended for the further exploration of specific SAMs for the detection and removal of PFASs.Finally,this review identifies the challenges and opportunities for development of SAMs for the detection and remediation of PFASs,providing an outlook on strategic goals for a green economy and sustainable development.
文摘[Objectives]To extract and purify perfluoroalkyl and polyfluoroalkyl substances(PFAS)from aquatic products and determine the optimal pretreatment conditions.[Methods]The QuEChERS method was employed for the extraction and purification of PFAS in aquatic products.The detection of PFAS was carried out using liquid chromatography-tandem mass spectrometry(LC-MS/MS)in ESI negative ion mode with multiple reaction monitoring(MRM),and quantification was performed using the external standard method.By optimizing instrument parameters such as ion source temperature,spray voltage,and collision energy,high selectivity and sensitivity of the detection were ensured.[Results]The established calibration curves for 28 PFAS compounds compounds,covering a range of 0.02 to 20 ng/mL,demonstrated excellent linearity.Spike recovery tests yielded limits of detection(LOD)between 0.02 and 0.5μg/kg for the 28 PFAS compounds compounds,with recovery rates ranging from 72.2%to 113.0%.[Conclusions]The method established in this study demonstrates excellent linearity,and is accurate,reliable,efficient,simple,and rapid.It possesses considerable practical applicability and can be used for the quality and risk assessment of 28 PFAS compounds compounds in aquatic products,indicating high practical utility.
基金Project supported by National Natural Science Foundation,Grant approval numbers 29472074 and 29632003
文摘In this article, the synthesis and characterization of a novel fluoromonomer and its copolymer with acrylamide is reported. 2-perfluoroamyl-4-hydroxylquinoline 2 was synthesized from ethyl 2, 2-dihydroperfluoroheptanoate in high yields. The monomer 4 was then synthesized from 2 in two steps readily in high yields. Synthesis and characterization of copolymers of acrylamide (AM) and the fluoromonomer were investigated. The composition and intrinsic viscosity of these copolymers were studied. It was found that the rheological properties of aqueous solutions of polyacrylamide were modified significantly when a small proportion of the fluoromonomer 4 was incorporated on investigating the viscosity-concentration profiles, pseudoplasticity of these solutions and the effect of the presence of surfactant. These results could be explained by the hydrophobic association of the fluorocarbon segments in the aqueous solutions of these copolymers.
基金funded by the National Natural Science of Foundation of China(Nos.21537001 and 21407033)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB14010100)
文摘The purpose of this study was to determine perfluoroalkyl substances（PFASs） in human serum, urine, hair and nail from general populations, and to investigate the possibility for human urine, hair and nail used as the biomonitoring sample for PFASs exposure. We detected the concentrations of PFHx A, PFOA, PFNA, PFDA, PFUn DA, PFDo A, PFHx S and PFOS in 39 matched human serum, urine, hair and nail samples from Shenzhen in China. The detection frequency and the median level of PFOS were all higher than that of the other PFASs in four matrices. The median concentration of PFOS in serum, urine, hair, and nail were 9.24 ng/mL, 13.96 ng/L, 0.58 ng/g and 0.63 ng/g, respectively. The results of spearman correlation test indicated that nail was an ideal matrix for biomonitoring PFOS rather than human urine and hair in general populations for the non-invasive sampling.
基金supported by the National Natural Science Foundation of China(Nos.21537001and 21477030)the National Key Research and Development Program of China(No.2017YFC1600502)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB14010100)
文摘This study was conducted to examine the association of perfluoroalkyl substance（PFAS）exposure with gestational diabetes mellitus（GDM） risk and postpartum fasting blood glucose.We used a 1：2 matched case–control study with 84 GDM subjects and 168 healthy pregnant women from Beijing, China. The maternal blood was collected at 1–2 days before delivery, and eight linear isomers and fourteen branched isomers were determined in maternal serum.Logistic regression analyses were performed to evaluate the associations after adjusting for potential confounders. The median of the sum of levels of total PFASs was 4.24 ng/m L with a interquartile range（IQR） of 2.82–6.54 ng/m L. Although maternal PFAS exposure was not associated with risk of GDM, significant positive associations were observed between evaluated exposure to specific PFAS congeners and increasing blood glucose. The odds ratio（ORs） of the highest category of postpartum fasting blood glucose for perfluoro-1-metylheptylsulfonat（1 m-PFOS）, perfluoro-3/4-metylheptylsulfonat（3 m＋4 m-PFOS）, perfluoro-5-metylheptylsulfonat（5 m-PFOS）, and perfluorohexane sulfonate（PFHx S） were 2.03（95% CI： 1.09–3.77）, 1.93（95% CI：1.04–3.58）, 2.48（95% CI： 1.33–4.65）, and 2.26（95% CI： 1.21–4.21）, respectively, suggesting negative effects of maternal exposure to specific PFAS compounds on glucose metabolism.
基金supported by the Major State Basic Research Development Program (No.2010CB951104)the National Science Foundation for Distinguished Young Scholars (No.51325902)+1 种基金the Specialized Research Fund for the Doctoral Program of Higher Education (No.20110003110030)the National Natural Science Foundation of China (No.51279010)
文摘The levels of six perfluoroalkyl substances（PFASs） in surface sediment and their vertical variations in dated sediment cores from the Haihe River were investigated; studied substances included perfluorooctanoic acid（PFOA）,perfluorononanoic acid（PFNA）,perfluorooctane sulfonate（PFOS）,perfluorodecanoic acid（PFDA）,perfluoroundecanoic acid（PFUnA）,and perfluorododecanoic acid（PFDoA）. Results showed that the total PFAS concentration in surface sediment ranged between 0.52 and 16.33 ng/g dry weight（dw） with an average of3.47 ng/g dw,with PFOS and PFOA as the dominant PFASs. In general,the PFAS concentrations in the mainstream increased from the upper to the lower reaches,except that a drop occurred downstream of the Erdao dam. Although the PFASs in the sediment cores did not show a clear decreasing or increasing trend with depth,the three cores had a similar vertical variation.The PFAS levels were relatively low in the surface sediment,and reached the first high point at8–20 cm as a result of the wide use of PFASs from 1990 to 2000. After that the PFAS levels decreased,and then increased to a second high point at about 40–48 cm,which might be caused by the leaching of PFASs in sediment. Because PFASs have hydrophilic groups and relatively high solubility,the PFASs will transfer from the upper to lower layers of sediment when water infiltration occurs,leading to the fluctuation of PFAS levels in sediment cores. This study suggests that both the temporal variation of sources and transfer processes of PFASs in sediments are important factors influencing the vertical variation of PFASs in sediment cores.
基金supported by the National Natural Science Foundation of China (Nos. 41907321, 21777182)the Natural Science Foundation of Hebei Province (No. B2019208273)State Key Laboratory of Environmental Chemistry and Ecotoxicology, RCEES, Chinese Academy of Sciences (No. KF2018-17)。
文摘It is extremely important to analyze the contaminative behaviors of Perfluoroalkyl acids(PFAAs) due to their serious threats to urban environments which are closely related to humans. Current study aimed to explore the distribution, source apportionment and ecological risk assessment of PFAAs in surface water from Shijiazhuang, China. The concentrations of ΣPFAAs ranged from 19.5 to 125.9 ng/L in the investigation area. Perfluorobutanesulfonic acid(PFBS) and perfluoropentanoic acid(PFPeA) were the predominant contaminants(mean value: 14.3 ng/L and 16.6 ng/L, respectively). The distribution of PFAAs according to geospatial analysis and hierarchical clustering analysis(HCA) showed that higher levels of ΣPFAAs were detected in the southern surface water of Shijiazhuang and there was a stepwise decrease from the wet season to the dry season. Furthermore, based on source apportionment,the dominant potential sources were found to be wastewater treatment plant(WWTP) effluents and industrial discharge. The risk quotients(RQs) revealed low ecological risks of all PFAAs for aquatic organisms in Shijiazhuang surface water. Collectively, this study provided basic data for regulatory strategies for controlling PFAA pollutions in urban surface water.
文摘Imagine if a group of toxic substances that increase oxidative stress and disrupt glucose and lipid metabolism have been broadly used worldwide for applications such as repellent,food packaging,and non-stick frying pan coatings.Now imagine if some of these substances have half-lives as long as 3-8 years.
基金supported by the National Key R&D Program of China (No. 2018YFA0901200)the National Natural Science Foundation of China (Nos. 21876194 and 21677170)
文摘Many per-and polyfluoralkyl substances(PFASs)may disrupt maternal thyroid hormone homeostasis in pregnancy.Concerns should be raised regarding the PFASs exposure in pregnant women because thyroid hormones are involved in the early development of the fetus.In this study,we measured the concentrations of 13 PFASs,including five novel shortchain PFASs,in serum from 123 pregnant women in Beijing,China.Linear regression models were used to investigate the association between thyroid-stimulating hormone(TSH)or free thyroxine(FT4)levels and PFASs concentrations under consideration of the impacts of pregnancy-induced physiological factors.We found that perfluorobutanoic acid(PFBA)(β=0.189,95%CI=-0.039,0.417,p=0.10)and perfluorodecanoic acid(PFDA)(β=-0.554,95%CI=-1.16,0.049,p=0.071)were suggestive of significant association with TSH in thyroid peroxidase antibody(TPOAb)negative women.No association was observed between all PFASs and FT4 levels after controlling for these confounding factors,such as BMI,gestational weight gain and maternal age.These findings suggest that it should pay more attention to the association between thyroid hormone levels and short-chain PFASs concentrations.Future studies could consider a greater sample and the inclusion of other clinical indicators of thyroid function,such as free T3 and total T3.
基金supported by the Mega-projects of Science Research for Water Environmental Improvement(No.2012ZX07101-002)the National Natural Science Foundation of China(No.41521003)
文摘Receptor models have been proved as useful tools to identify source categories and quantitatively calculate the contributions of extracted sources.In this study,sixty surface sediment samples were collected from fourteen lakes in Jiangsu Province,China.The total concentrations of C_4–C_（14）-perfluoroalkyl carboxylic acids and perfluorooctane sulfonic acid（∑_（12）PFASs） in sediments ranged from 0.264 to 4.44 ng/g dw（dry weight）,with an average of 1.76 ng/g dw.Three commonly-applied receptor models,namely principal component analysis-multiple linear regression（PCA-MLR）,positive matrix factorization（PMF） and Unmix models,were employed to apportion PFAS sources in sediments.Overall,these three models all could well track the ∑_（12） PFASs concentrations as well as the concentrations explained in sediments.These three models identified consistently four PFAS sources：the textile treatment sources,the fluoropolymer processing aid/fluororesin coating sources,the textile treatment/metal plating sources and the precious metal sources,contributing 28.1%,37.0%,29.7% and 5.3% by PCA-MLR model,30.60%,39.3%,22.4% and 7.7% by PMF model,and 20.6%,52.4%,20.2% and 6.8% by Unmix model to the ∑_（12） PFASs,respectively.Comparative statistics of multiple analytical methods could minimize individual-method weaknesses and provide convergent results to enhance the persuasiveness of the conclusions.The findings could give us a better knowledge of PFAS sources in aquatic environments.
基金supported by the Medical University of South Carolina Center for Global Healthsupported by the South African Research Chairs Initiative of the Department of Science and Technology and National Research Foundation (NRF) of South Africa (Grant No 101054)
文摘This study examined concentrations of 15 perfluoroalkyl acids（PFAAs） in tissues from male Mozambique tilapia（Oreochromis mossambicus） collected at Loskop Dam, Mpumalanga,South Africa in 2014 and 2016. Nine of the 15 PFAAs were detected frequently and were included in statistical analysis and included two of the most commonly known PFAAs,perfluorooctanesulfonic acid（PFOS）（median, 41.6 ng/g） and perfluorooctanoic acid（PFOA）（median, 0.0825 ng/g）. Of the tissues measured, plasma（2016 and 2014 median, 22.2 ng/g）contained the highest PFAA burden followed by（in descending order）： liver（median,11.6 ng/g）, kidney（median, 9.04 ng/g）, spleen（median, 5.92 ng/g）, adipose（median, 2.54 ng/g）, and muscle（median, 1.11 ng/g）. Loskop Dam tilapia have been affected by an inflammatory disease of the adipose tissue known as pansteatitis, so this study also aimed to investigate relationships between PFAA tissue concentrations and incidence of pansteatitis or fish health status. Results revealed that healthy tilapia exhibited an overall higher（p-value 〈 0.05） PFAA burden than pansteatitis-affected tilapia across all tissues.Further analysis showed that organs previously noted in the literature to contain the highest PFAA concentrations, such as kidney, liver, and plasma, were the organs driving the difference in PFAA burden between the two tilapia groups. Care must be taken in the interpretations we draw from not only the results of our study, but also other PFAA measurements made on populations（human and wildlife alike） under differing health status.
基金supported by the National Natural Science Foundation of China(Nos.21377145,21321004)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB01020300)
文摘An on-line solid phase extraction-high performance liquid chromatography-tandem mass spectrometry method for the analysis of perfluoroalkyl substances（PFASs） in water samples was developed.The optimal analytical conditions were obtained through the optimization of the extraction efficiency of online solid phase extraction column,sample loading rate and loading volume,and the concentration of ammonium acetate in mobile phase.Under the optimal condition,the analytical method displayed good linearity（r^2〉0.99） for 12 PFASs（C5-C14 perfluoroalkyl carboxylic acids and C6/C8 perfluoroalkyl sulfonic acids） over a concentration range of 0.5-100 ng/L.The limits of quantitation for samples were between 0.025 ng/L and 0.5 ng/L and the relative standard deviations（RSD） of five consecutive analyses were less than 10%for 1 ng/L standard solution.Satisfactory results were obtained using this analytical method for the analysis of perfluoroalkyl substances in Antarctic ice core samples.The recoveries of all perfluoroalkyl substances were in a range of 73%-117%when the samples were spiked with standards at the concentrations of 2.5 ng/L and 25 ng/L.
