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Secondary aerosol formation and oxidation capacity in photooxidation in the presence of Al_2O_3 seed particles and SO_2

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Science China Chemistry 2015年第9期58卷 1426-1434页

作者： Biwu Chu Tengyu Liu Xiao Zhang Yongchun Liu Qingxin Ma Jinzhu Ma Hong He Xinming Wang Junhua Li Jiming Hao State Key Joint laboratory of Environment Simulation and Pollution Control Research Center for Eco-Environmental Sciences Chinese Academy of Sciences State Key laboratory of organic geochemistry Guangzhou Institute of geochemistry Chinese Academy of Sciences School of Environment Tsinghua University Nanjing University of Information Science & Technology

To investigate the sensitivity of secondary aerosol formation and oxidation capacity to NOx in homogeneous and heterogeneous reactions, a series of irradiated toluene/NOx/air and ?-pinene/NOx/air experiments were conducted in smog chambers in the absence or presence of Al2O3 seed particles. Various concentrations of NOx and volatile organic compounds(VOCs) were designed to simulate secondary aerosol formation under different scenarios for NOx. Under "VOC-limited" conditions, the increasing NOx concentration suppressed secondary aerosol formation, while the increasing toluene concentration not only contributed to the increase in secondary aerosol formation, but also led to the elevated oxidation degree for the organic aerosol. Sulfate formation was suppressed with the increasing NOx due to a decreased oxidation capacity of the photooxidation system. Secondary organic aerosol(SOA) formation also decreased with the presence of high concentration of NOx, because organo-peroxy radicals(RO2) react with NOx instead of with peroxy radicals(RO2 or HO2), resulting in the formation of volatile organic products. The increasing concentration of NOx enhanced the formation of sulfate, nitrate and SOA under "NOx-limited" conditions, in which the heterogeneous reactions played an important role. In the presence of Al2O3 seed particles, a synergetic promoting effect of mineral dust and NOx on secondary aerosol formation in heterogeneous reactions was observed in the photooxidation. This synergetic effect strengthened the positive relationship between NOx and secondary aerosol formation under "NOx-limited" conditions but weakened or even overturned the negative relationship between NOx and secondary aerosol formation under "VOC-limited" conditions. Sensitivity of secondary aerosol formation to NOx seemed different in homogeneous and heterogeneous reactions, and should be both taken into account in the sensitivity study. The sensitivity of secondary aerosol formation to NOx was further

关键词： secondary aerosol oxidation capacity synergetic promoting effect Al2O3 seed particles sensitivity

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Theoretical Study of Small Water Clusters of Sulfur Dioxide

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Chinese Journal of Structural Chemistry 2010年第4期29卷 499-508页

作者：赵亚英曾永平张锡辉陶福明 Research Center of Environmental Engineering and Management Graduate School at Shenzhen Tsinghua University State Key laboratory of organic geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences Department of Chemistry and Biochemistry California State University

The intermolecular clusters of sulfur dioxide with water, SO2（H2O）n （n = 2～5）, are studied by using B3LYP density functional theory and MP2 ab initio methods along with the large basis sets （6-311＋＋G（d,p） and aug-cc-pVDZ）. The equilibrium geometries, intermolecular binding energies, and anharmonic frequencies of the clusters are calculated and compared with those of pure water clusters and available experiments. SO2 tends to form cyclic hydrogen-bonded complexes with two or three water molecules. In the larger clusters, however, water molecules begin to retain the structure of pure water clusters and segregate from SO2. Infrared absorption assignments for the small clusters are discussed to resolve a possible incorrect assignment in a recent spectroscopic experiment on the clusters.

关键词： SO Theoretical Study of Small Water Clusters of Sulfur Dioxide LYP MP

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Determining the Main Gas-generation Phase of Marine organic Matters in Different Occurrence States using the Kinetic Method

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Acta Geologica Sinica(English Edition) 2008年第1期82卷 197-205页

作者： WANG Yunpeng ZHAO Changyi WANG Zhaoyun WANG Hongjun ZOU Yanrong LIU Jinzhong ZHAO Wenzhi LIU Dehan LU Jialan State Key laboratory of organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

This paper probes the determination of the main gas-generation phase of marine organic mattes using the kinetic method. The main gas-generation phase of marine organic matters was determined by coupling the gas generation yields and rates in geological history computed by the acquired kinetic parameters of typical marine organic matters （reservoir oil, residual bitumen, lowmaturity kerogen and residual kerogen） in both China and abroad and maturity by the EasyRo（%） method. Here, the main gas-generation phase was determined as Ro%=1.4%-2.4% for type Ⅰ kerogen, Ro%=1.5-3.0% for low-maturity type Ⅱ kerogen, Ro%=1.4-2.8% for residual kerogen, Ro%=1.5-3.2% for residual bitumen and Ro%=1.6-3.2% for reservoir oil cracking. The influences on the main gas-generation phase from the openness of the simulated system and the ＂dead line＂ of natural gas generation are also discussed. The results indicate that the openness of simulation system has a definite influence on computing the main gas-generation phase. The main gas-generation phase of type Ⅱ kerogen is Ro%=1.4-3.1% in an open system, which is earlier than that in a closed system. According to our results, the ＂dead line＂ of natural gas generation is determined as Ro=3.5 % for type Ⅰ kerogen, Ro=4.4-4.5% for type Ⅱ kerogen and Ro=4.6% for marine oil. Preliminary applications are presented taking the southwestern Tarim Basin as an example.

关键词： marine organic matter kerogen oil cracking hydrocarbon generating kinetics main gasgeneration phase southwestern Tarim Basin gas source kitchen

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A Density Functional Theory Study of the Hydrates of 2NH_3:H_2SO_4 and Its Implications for the Formation of Atmosphere Particles

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Chinese Journal of Structural Chemistry 2010年第4期29卷 525-534页

作者：赵亚英曾永平张锡辉马琳陶福明 Research Center of Environmental Engineering and Management Graduate School at ShenzhenTsinghua University State Key laboratory of organic geochemistry Guangzhou Institute of GeochemistryChinese Academy of Sciences Department of Chemistry and Biochemistry California State University

Density functional theory was used at the B3LYP/6-311＋＋G（d,p） level of theory to study the hydrates of 2NH3：H2SO4：nH2O for n = 0～4. Neutrals of the most stable clusters, when n = 0 and 1, spontaneously formed and were determined to be hydrogen-bonded molecular complexes of monomeric species. Double ions （clusters containing a NH4＋ cation and a HSO4- anion） or even ternary ions （clusters with two NH4＋ cations and one SO42- anion） spontaneously formed in the most stable clusters of 2NH3：H2SO4：nH2O （n = 2, 3, 4）. The energetics of binding and incremental association was also calculated. Double ions are not energetically favorable until 2NH3：H2SO4：2H2O because of the about equal free energies for forming the neutral （the most stable） and double ion （the second stable） isomers. The free energy of incremental association from free H2O and 2NH3：H2SO4：nH2O has a maximum at n = 2 at room temperature with ΔG ≈ –2 kcal/mol. The comparison of incremental association energies between 2NH3：H2SO4：nH2O, NH3：H2SO4：nH2O and H2SO4：nH2O clusters revealed that NH3 plays an important role in the atmospheric particle nucleation.

关键词： 2NH3:H2SO4:nH2O (n = 0~4) molecular complexes incremental association density functional theory

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The distribution of phenylalkanes in the modern sediment associated with gas hydrate from the Gulf of Mexico

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Acta Oceanologica Sinica 2008年第6期27卷 71-82页

作者： WANG Cuiping SUN Hongwen SONG Zhiguang ZHANG Tao College of Environmental Science and Engineering Nankai University Tianjin 300071 China State Key laboratory of organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Phenylalkanes with carbon numbers between 16 and 19, characterized by the main carbon-18, have been identified in the modern sediments collected from gas hydrate area from the Gulf of Mexico. The structure of phenylalkanes with four isomers for every carbon number was determined by means of their mass spectra and previous studies. The distribution of the series characterized by a low molecular mass was similar to the distribution of n-alkane, alkylcyclohexanes and alkylbenzenes in each sample. There were differences in the distribution of the phenylalkane series between the S - 1, S - 4, S - 7, S - 9 samples and the S - 8, S - 10 and S - 11 samples. The phenylalkanes might be derived from Archaea associated with anaerobic oxidation of methane （AOM） processes in S - 1, S -4, S -7 and S -9 samples according to their distribution resembled with the distribution of the extract from a type of Archaea. The distribution of alkylcyclohexanes and alkylbenzenes in S - 1, S - 4, S - 7 and S - 9 sample was found to be similar to each other. The odd-over-even predominance of alkylcyclohexanes was seen as the input of some bac- terial.

关键词： phenylalkane gas hydrate Gulf of Mexico

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Water quality criteria for 4-nonylphenol in protection of aquatic life

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Science China Earth Sciences 2012年第6期55卷 892-899页

作者： LEI BingLi LIU Qian SUN YanFeng WANG YiPei YU ZhiQiang ZENG XiangYing FU JiaMo SHENG GuoYing lnstitute of Environmental Pollution and Health College of Environmental and Chemical Engineering Shanghai University Shanghai 200444 China State Key laboratory of organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

Here reproduction and death toxicity data were selected for 4-nonylphenol based on endocrine disrupting properties of the re- productive system. Assessment factor （AF） and species sensitivity distribution （SSD） curve were employed to derive criteria maximum concentration （CMC） and criteria continuous concentration （CCC） of three different 4-nonylphenols for protection of aquatic life. The results showed that the CMC and CCC based on SSD method and death toxicity data for three different 4-nonylphenols （CAS No： 104405, 25154523, 84852163） were 26.7, 13.6, 3.84μg L-1 and 8.86, 2.21, 0.97 μg L-1, respectively. Based on SSD and reproductive toxicity data, the CCC values of different 4-nonylphenols （CAS No： 104405, 25154523） were 1.59 and 1.34μg L-l, respectively. The CCC values obtained by the AF for three different 4-nonylphenol （CAS No： 104405, 25154523, 84852163） were 0.165, 1.03, 0.74 μg L -1 and 0.5, 0.5, 0.1μg L-1, respectively, based on death toxicity data and re- productive toxicity data. The CCC values obtained by AF were all lower than the corresponding criteria values obtained by SSD, and the CCC values based on reproductive toxicity data were less than those based on the death toxicity data. This study provides a useful method for deriving water quality criteria for endocrine disruptors.

关键词： 4-nonylphenol toxicity endpoint assessment method aquatic quality criteria

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Application of C5-C13 light hydrocarbons in depositional environment diagnosis

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Progress in Natural Science:Materials International 2008年第9期18卷 1129-1137页

作者： Peirong Wanga,b,, Guanjun Xu a,c, Tingrong Xiaoc, Dajiang Zhanga,c, Bin Zhanga,c a Key laboratory of Petroleum geochemistry, China National Petroleum Corporation, Beijing 100083, China b Department of organic geochemistry, Yangtze University, Jingzhou 434023, China c Central laboratory of Petroleum Geology, Research Institute of Petroleum Exploration and Development, PetroChina, Beijing 100083, China Key laboratory of Petroleum geochemistry China National Petroleum Corporation Beijing 100083 China Department of organic geochemistry Yangtze University Jingzhou 434023 China Central laboratory of Petroleum Geology Research Institute of Petroleum Exploration and Development PetroChina Beijing 100083 China

Based on the geological background and Gammacerane/C31H(S + R) ratios, source rock depositional environments of the studied oil samples (194) from 13 oilfields were classified into three groups according to salinity:saline-lacustrine facies, fresh to brackish lacustrine facies (including limnetic facies), and semi-saline to saline facies (including marine facies of the Tarim Basin).C5-C13 compound groups in the crude oils were separated by GC, and about 286 compounds were qualitatively *** geochemical application of the C6-C13 compound groups and their ratios between each group with individual carbon number was *** studies show that (1) C6-C13 compound groups and their ratios in the crude oils could serve as new reliable parameters for oil-oil correlation because the C6-C13 light fractions are the major oil component, especially in light oil or condensate, in which they account for almost 90% of the whole oil;(2) the compound groups of C7 light hydrocarbons in oils derived from difierent depositional environments with difierent salinity have difierent characteristics;(3) C6-C13 compound groups and ratios may be afiected by other factors such as maturity, but they are mainly controlled by salinity of depositional waters.

关键词： Light hydrocarbons Crude oil Depositional environment Salinity

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Organochlorine compounds and polycyclic aromatic hydrocarbons in surface sediment from Baiyangdian Lake,North China:Concentrations,sources profiles and potential risk

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Journal of Environmental Sciences 2010年第2期22卷 176-183页

作者： Guocheng Hu Xiaojun Luo Fengchao Li Jiayin Dai Jianyang Guo Shejun Chen Cao Hong Bixian Mai Muqi Xu Key laboratory of Animal Ecology and Conservation Biology Institute of Zoology Chinese Academy of Sciences Beijing 100101 China. State Key laboratory of organic Chemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China College of Science Life Hebei University Baoding 071002 China State Key laboratory of Environmental geochemistry Institute of Geochemistry Chinese Academy of Sciences Guiyang 55002 China

Organochlorine pesticides （OCPs）, polychlorinated biphenyls （PCBs）, and polycyclic aromatic hydrocarbons （PAHs） were determined in nineteen surface sediment samples collected from Baiyangdian Lake and its inflowing river （Fuhe River） in North China. Total concentrations of OCPs, PCBs and PAHs in sediments ranged from 5.4 to 707.6 ng]g, 2.3 to 197.8 ng/g, and 101.3 to 6360.5 ng]g, respectively. The levels of contaminants in Fuhe River were significantly higher than those in Baiyandian Lake. For hexachlorocyclohexane （HCHs） and dichlorodiphenytrich/oroethanes （DDTs）, α-HCH and p,p＇-DDT were predominant isomers; while for PCBs, PCB 28/31, PCB 40/103, PCB 60, PCB 101, and PCB 118 were predominant congeners. Possible sources derived from historical usage for OCPs and incomplete combustion fuel, wood, and coal and exhaustion of boats or cars for PAHs. Risk assessment of sediment indicated that sediments in Fuhe River were likely to pose potential biological adverse impact.

关键词： persistent organic pollutants concentrations profiles risk assessment Baiyangdian Lake

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Chemical characteristics of PM_(2.5) during a typical haze episode in Guangzhou

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Journal of Environmental Sciences 2009年第6期21卷 774-781页

作者： TAN Jihua DUAN Jingchun HE Kebin MA Yongliang DUAN Fengkui CHEN Yuan FU Jiamo Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China Chinese Research Academy of Environmental Sciences Beijing 100012 China State Key laboratory of organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

The chemical characteristics（water-soluble ions and carbonaceous species） of PM2.5 in Guangzhou were measured during a typical haze *** of the chemical species in PM2.5 showed significant difference between normal and haze *** highest contributors to PM2.5 were organic carbon（OC）,nitrate,and sulfate in haze days and were OC,sulfate,and elemental carbon（EC） in normal *** concentrations of secondary species such as,NO3^-,SO4^2-,and NH4^＋ in haze days were 6.5,3.9,and 5.3 times higher than those in normal days,respectively,while primary species（EC,Ca^2＋,K^＋） show similar increase from normal to haze days by a factor about ***/EC ratio ranged from 2.8 to 6.2 with an average of 4.7 and the estimation on a minimum OC/EC ratio showed that SOC（secondary organic carbon） accounted more than 36.6% for the total organic carbon in haze *** significantly increase in the secondary species（SOC,NO3^-,SO4^2-,and NH4^＋）,especially in NO3^-,caused the worst air quality in this ***,the result illustrated that the serious air pollution in haze episodes was strongly correlated with the meteorological *** the sampling periods,air pollution and visibility had a good relationship with the air mass transport distance;the shorter air masses transport distance,the worse air quality and visibility in Guangzhou,indicating the strong domination of local sources contributing to haze *** concentration of the secondary aerosol in haze episodes was likely due to the higher oxidation rates of sulfur and nitrogen species.

关键词： PM2.5 haze episode water-soluble inorganic ions organic carbon elemental carbon Guangzhou

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Characterizing the antibiotic resistance genes in a river catchment： Influence of anthropogenic activities

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Journal of Environmental Sciences 2018年第7期30卷 125-132页

作者： Haoyu Jiang Renjun Zhou Ying Yang Baowei Chen Zhineng Cheng Mengdi Zhang Jun Li Gan Zhang Shichun Zou School of Marine Sciences Sun Yat-Sen University Guangzhou 510006 China State Key laboratory of organic geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China Graduate University of the Chinese Academy of Sciences Beijing 100039 China

Previous studies on environmental antibiotics resistance genes（ARGs） have focused on the pollution sources such as wastewater treatment plants, aquaculture and livestock farms,etc. Few of them had addressed this issue in a regional scale such as river catchment. Hence,the occurrence and abundances of 23 ARGs were investigated in surface water samples collected from 38 sites which located from the river source to estuary of the Beijiang *** them, 11 ARGs were frequently detected in this region and 5 ARGs（sul Ⅰ, sul Ⅱ, tet B,tet C, and tet W） were selected for their distribution pattern analysis. The abundances of the selected ARGs were higher in the upstream（8.70 × 10^6 copies/ng DNA） and downstream areas（3.17 × 10^6 copies/ng DNA） than those in the midstream areas（1.23 × 10^6 copies/ng DNA）, which was positively correlated to the population density and number of pollution sources. Pollution sources of ARGs along the Beijiang River not only had a great impact on the abundances and diversity, but also on the distribution of specific ARGs in the water samples. Both sul Ⅰ and sul Ⅱ were likely originated from aquaculture farms and animal farms,tet W gene was possibly associated with the mining/metal melting industry and the electric waste disposal and tet C gene was commonly found in the area with multiple pollution ***, the abundance of tet B was not particularly related to anthropogenic impacts. These findings highlight the influence of pollution sources and density of population on the distribution and dissemination of ARGs at a regional scale.

关键词： Antibiotic resistance genes Anthropogenic activities Pollution sources River catchment

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