10 samples of sediments obtained from the South Mid-Atlantic Ridge were measured for the abundances and distributions of polycyclic aromatic compounds（PAHs）. The total concentrations of PAHs（∑PAHs） ranged from 2....10 samples of sediments obtained from the South Mid-Atlantic Ridge were measured for the abundances and distributions of polycyclic aromatic compounds（PAHs）. The total concentrations of PAHs（∑PAHs） ranged from 2.768 to 9.826 μg/g dry sediment. The ∑PAHs was higher in sample 22V-TVG10 and sample 26V-TVG05 which were close to hydrothermal fields, with the lowest value in sample 22V-TVG14 which was farthest from hydrothermal fields, suggesting a probable hydrothermal origin of ∑PAHs of samples. Approximately nine kinds of PAHs were identified, and low molecular mass tricyclic and tetracyclic aromatic compounds were predominant in the samples. The concentrations of fluoranthene which were typical as hydrothermal alteration compounds were the highest among PAHs with dry weight between 0.913–3.157 μg/g. The phenanthrene homologue was most abundant in the samples, and the ratios between parent phenanthrene and methylphenanthrene which probably reflected the degree of hydrothermal alteration ranged from 0.097 to 1.602. The sample 22V-TVG10 possessing a maximum ratio value showed the intense influence of the hydrothermal alteration on this sample, which might further imply that PAHs in sediments were mainly derived from the hydrothermal alteration.展开更多
A comprehensive summary for the study on the monitoring of potential carcinogenicpolycyclic aromatic compounds (PACs) in the emission of coal combustion is presented in this pa-per. Some PACs in the stack gases of coa...A comprehensive summary for the study on the monitoring of potential carcinogenicpolycyclic aromatic compounds (PACs) in the emission of coal combustion is presented in this pa-per. Some PACs in the stack gases of coal-fired boiler have been determined with a procedure whichconsists of isokinetic stack sampling, extraction, preseparation and some instrumental analysis stepssuch as gas chromatographylmass spectrometry (GC/MS), high performance liquid chromatographyfHPLC), room temperature phosphorimetry (RTP) and synchronous fluorescence spectroscopy (SFS)and so on. The results indicate that the air pollution of PACs in China are related closely to thecoal combustion.展开更多
The physical growth of Polycyclic Aromatic Compounds(PACs)to soot particles plays a significant role in understanding the chemistry of soot formation.Insights into the process can be gained from PACs’free energy of d...The physical growth of Polycyclic Aromatic Compounds(PACs)to soot particles plays a significant role in understanding the chemistry of soot formation.Insights into the process can be gained from PACs’free energy of dimerization landscape.However,because the infeasibly large space of possible PAC dimers cannot be exhaustively simulated,researchers must train machine learning models on a subset of data to impute the rest.To this end,we propose and assess an active learning approach to discovering the optimal PACs for training a machine learning model to predict PACs’association and dissociation free energies.The comparison between active learning and random sampling showed that active learning has faster loss convergence,requiring fewer training samples to reach the same level of accuracy.The trained model accurately modeled unseen PACs and exhibited robustness against changes in the sampling space used to train the model.More broadly,this work shows how active learning can optimize the design and improve the understanding of more expensive models in specific domains.展开更多
Large igneous provinces (LIPs), a critical area in Earth science, are closely related to paleoenvironmental evolution and biodiversity. The Permian Tarim large igneous province (TLIP) provides an ideal laboratory for ...Large igneous provinces (LIPs), a critical area in Earth science, are closely related to paleoenvironmental evolution and biodiversity. The Permian Tarim large igneous province (TLIP) provides an ideal laboratory for correlational research. Previous reports show that the TLIP formed ∼300–262 Ma. Based on igneous lithology and the upper limit of single magmatic activity (<5 Ma), the TLIP can be divided into five main magmatic episodes. Core logging, seismic sections, lithofacies observations, and in-situ calcite U-Pb dating indicate diabase intrusions and a hydrothermal upwelling event (∼295.9–273 Ma) resulted from TLIP magmatic activity. The results indicate that polycyclic aromatic compounds (PACs) in oil are powerful proxies of magmatic intrusion and hydrothermal activity in the Permian TLIP. The existing diabase intrusion (EDI) samples show a higher concentration of high-molecular-weight (HMW) PACs (≥5-ring PACs) and greater combustion-derived PAC ratios. The distribution coupling between the diabase intrusion and PACs indicates that the HMW PACs are mainly derived from the cycloaddition reactions by the pyrogenic source (i.e., diabase intrusion). The conversion of phenanthrene (Phe), biphenyl (Bp), and dibenzothiophene (DBT) series compounds indicates that the oil is altered by hydrothermal activity. The hydrogenium and sulfur carried by the hydrothermal upwelling process promote the heteroatom incorporation of PACs. The cycloaddition and heteroatom incorporation reactions of PACs during the formation of LIPs offer a new perspective for evaluating their impact. PACs serve as effective proxies for LIPs and may also contribute to biological crises associated with LIPs.展开更多
To characterize how the speed and load of a medium-duty diesel engine affected the organic compounds in diesel particle matter（PM） below 1 μm, four driving conditions were examined. At all four driving conditions, ...To characterize how the speed and load of a medium-duty diesel engine affected the organic compounds in diesel particle matter（PM） below 1 μm, four driving conditions were examined. At all four driving conditions, concentration of identifiable organic compounds in PM ultrafine（34–94 nm） and accumulation（94–1000 nm） modes ranged from 2.9 to 5.7 μg/m3 and 9.5 to 16.4 μg/m3, respectively. As a function of driving conditions, the non-oxygencontaining organics exhibited a reversed concentration trend to the oxygen-containing organics. The identified organic compounds were classified into eleven classes： alkanes,alkenes, alkynes, aromatic hydrocarbons, carboxylic acids, esters, ketones, alcohols, ethers,nitrogen-containing compounds, and sulfur-containing compounds. At all driving conditions,alkane class consistently showed the highest concentration（8.3 to 18.0 μg/m3） followed by carboxylic acid, esters, ketones and alcohols. Twelve polycyclic aromatic hydrocarbons（PAHs）were identified with a total concentration ranging from 37.9 to 174.8 ng/m3. In addition, nine nitrogen-containing polycyclic aromatic compounds（NPACs） were identified with a total concentration ranging from 7.0 to 10.3 ng/m3. The most abundant PAH（phenanthrene）and NPACs（7,8-benzoquinoline and 3-nitrophenanthrene） comprise a similar molecular（3 aromatic-ring） structure under the highest engine speed and engine load.展开更多
In this report we investigated two-dimensionally triptycene end-capped QPPs in terms of their solution and solid-state behavior.For this purpose,a triphenylene based ortho-diamine decorated with two triptycenyl units ...In this report we investigated two-dimensionally triptycene end-capped QPPs in terms of their solution and solid-state behavior.For this purpose,a triphenylene based ortho-diamine decorated with two triptycenyl units as well as a phenylene diamine with two non-annulated triptycene units have been synthesized.Sequences of condensation reactions with a pyrene-based tetraketone and ortho-diamines yielded a series of QPPs and UV/Vis investigations of the corresponding compounds led to the conclusion,that the QPPs form dimers in solution,which was further supported by MALDI-TIMS-TOF-MS.Single-crystal X-ray analysis of the triply and quadruply triptycene end-capped QPPs furthermore showed shortπ-π-distances of 3.3-3.4?and a perfect shape match during the dimerization of the triply triptycenyl end-capped QPP making it possible synthon for crystal engineering.展开更多
基金The National Key Basic Research Program of China under contract No.2013CB429700the National Special Fund for the 12th Five Year Plan of COMRA under contract Nos DY125-12-R-02,DY125-12-R-05 and DY125-11-R-05+2 种基金the National Natural Science Foundation of China under contract Nos 41325021,40830849 and 40976027the Strategic Priority Research Program of the Chinese Academy of Sciences under contract No.XDA11030302the Shandong Province Natural Science Foundation of China for Distinguished Young Scholars under contract No.JQ200913
文摘10 samples of sediments obtained from the South Mid-Atlantic Ridge were measured for the abundances and distributions of polycyclic aromatic compounds（PAHs）. The total concentrations of PAHs（∑PAHs） ranged from 2.768 to 9.826 μg/g dry sediment. The ∑PAHs was higher in sample 22V-TVG10 and sample 26V-TVG05 which were close to hydrothermal fields, with the lowest value in sample 22V-TVG14 which was farthest from hydrothermal fields, suggesting a probable hydrothermal origin of ∑PAHs of samples. Approximately nine kinds of PAHs were identified, and low molecular mass tricyclic and tetracyclic aromatic compounds were predominant in the samples. The concentrations of fluoranthene which were typical as hydrothermal alteration compounds were the highest among PAHs with dry weight between 0.913–3.157 μg/g. The phenanthrene homologue was most abundant in the samples, and the ratios between parent phenanthrene and methylphenanthrene which probably reflected the degree of hydrothermal alteration ranged from 0.097 to 1.602. The sample 22V-TVG10 possessing a maximum ratio value showed the intense influence of the hydrothermal alteration on this sample, which might further imply that PAHs in sediments were mainly derived from the hydrothermal alteration.
文摘A comprehensive summary for the study on the monitoring of potential carcinogenicpolycyclic aromatic compounds (PACs) in the emission of coal combustion is presented in this pa-per. Some PACs in the stack gases of coal-fired boiler have been determined with a procedure whichconsists of isokinetic stack sampling, extraction, preseparation and some instrumental analysis stepssuch as gas chromatographylmass spectrometry (GC/MS), high performance liquid chromatographyfHPLC), room temperature phosphorimetry (RTP) and synchronous fluorescence spectroscopy (SFS)and so on. The results indicate that the air pollution of PACs in China are related closely to thecoal combustion.
基金funded in part by the National Science Foundation Environmental Convergence Opportunities in Chemical,Bioengineering,Environmental,and Transport Systems(ECO-CBET)[Award Number:AWD024893]by the Michigan Institute for Computational Discovery and Engineering(MICDE)Research Scholar Program.
文摘The physical growth of Polycyclic Aromatic Compounds(PACs)to soot particles plays a significant role in understanding the chemistry of soot formation.Insights into the process can be gained from PACs’free energy of dimerization landscape.However,because the infeasibly large space of possible PAC dimers cannot be exhaustively simulated,researchers must train machine learning models on a subset of data to impute the rest.To this end,we propose and assess an active learning approach to discovering the optimal PACs for training a machine learning model to predict PACs’association and dissociation free energies.The comparison between active learning and random sampling showed that active learning has faster loss convergence,requiring fewer training samples to reach the same level of accuracy.The trained model accurately modeled unseen PACs and exhibited robustness against changes in the sampling space used to train the model.More broadly,this work shows how active learning can optimize the design and improve the understanding of more expensive models in specific domains.
基金funded by the National Natural Science Foundation of China(Grant No.42173054).
文摘Large igneous provinces (LIPs), a critical area in Earth science, are closely related to paleoenvironmental evolution and biodiversity. The Permian Tarim large igneous province (TLIP) provides an ideal laboratory for correlational research. Previous reports show that the TLIP formed ∼300–262 Ma. Based on igneous lithology and the upper limit of single magmatic activity (<5 Ma), the TLIP can be divided into five main magmatic episodes. Core logging, seismic sections, lithofacies observations, and in-situ calcite U-Pb dating indicate diabase intrusions and a hydrothermal upwelling event (∼295.9–273 Ma) resulted from TLIP magmatic activity. The results indicate that polycyclic aromatic compounds (PACs) in oil are powerful proxies of magmatic intrusion and hydrothermal activity in the Permian TLIP. The existing diabase intrusion (EDI) samples show a higher concentration of high-molecular-weight (HMW) PACs (≥5-ring PACs) and greater combustion-derived PAC ratios. The distribution coupling between the diabase intrusion and PACs indicates that the HMW PACs are mainly derived from the cycloaddition reactions by the pyrogenic source (i.e., diabase intrusion). The conversion of phenanthrene (Phe), biphenyl (Bp), and dibenzothiophene (DBT) series compounds indicates that the oil is altered by hydrothermal activity. The hydrogenium and sulfur carried by the hydrothermal upwelling process promote the heteroatom incorporation of PACs. The cycloaddition and heteroatom incorporation reactions of PACs during the formation of LIPs offer a new perspective for evaluating their impact. PACs serve as effective proxies for LIPs and may also contribute to biological crises associated with LIPs.
基金supported by the Transportation Pollution Research Center, National Institute of Environmental Research in the Republic of Korea and the Korean government overseas study fellowship (Program: 2003-S-20)
文摘To characterize how the speed and load of a medium-duty diesel engine affected the organic compounds in diesel particle matter（PM） below 1 μm, four driving conditions were examined. At all four driving conditions, concentration of identifiable organic compounds in PM ultrafine（34–94 nm） and accumulation（94–1000 nm） modes ranged from 2.9 to 5.7 μg/m3 and 9.5 to 16.4 μg/m3, respectively. As a function of driving conditions, the non-oxygencontaining organics exhibited a reversed concentration trend to the oxygen-containing organics. The identified organic compounds were classified into eleven classes： alkanes,alkenes, alkynes, aromatic hydrocarbons, carboxylic acids, esters, ketones, alcohols, ethers,nitrogen-containing compounds, and sulfur-containing compounds. At all driving conditions,alkane class consistently showed the highest concentration（8.3 to 18.0 μg/m3） followed by carboxylic acid, esters, ketones and alcohols. Twelve polycyclic aromatic hydrocarbons（PAHs）were identified with a total concentration ranging from 37.9 to 174.8 ng/m3. In addition, nine nitrogen-containing polycyclic aromatic compounds（NPACs） were identified with a total concentration ranging from 7.0 to 10.3 ng/m3. The most abundant PAH（phenanthrene）and NPACs（7,8-benzoquinoline and 3-nitrophenanthrene） comprise a similar molecular（3 aromatic-ring） structure under the highest engine speed and engine load.
基金grateful to"Deutsche Forschungsgemeinschaft"supporting this project(SFB1249"N-heteropolycyclic compounds as functional materials"TP-A04).support by the state of Baden-Wurttemberg through bwHPC and the German Research Foundation(DFG)through grant no.INST 40/575-1 FUGG(JUSTUS 2 cluster).
文摘In this report we investigated two-dimensionally triptycene end-capped QPPs in terms of their solution and solid-state behavior.For this purpose,a triphenylene based ortho-diamine decorated with two triptycenyl units as well as a phenylene diamine with two non-annulated triptycene units have been synthesized.Sequences of condensation reactions with a pyrene-based tetraketone and ortho-diamines yielded a series of QPPs and UV/Vis investigations of the corresponding compounds led to the conclusion,that the QPPs form dimers in solution,which was further supported by MALDI-TIMS-TOF-MS.Single-crystal X-ray analysis of the triply and quadruply triptycene end-capped QPPs furthermore showed shortπ-π-distances of 3.3-3.4?and a perfect shape match during the dimerization of the triply triptycenyl end-capped QPP making it possible synthon for crystal engineering.
