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381.
东濮凹陷盐湖相原油中杂原子化合物研究薄弱。采用高分辨率质谱技术、结合色谱-质谱,对东濮凹陷盐湖相、淡水湖相原油、烃源岩中的含氮、氧化合物进行了检测。结果表明,原油中含有丰富的氮、氧化合物, N1、O1和O2占绝对优势;随成熟度增加,N1和O1类化合物相对丰度增加、O2类化合物相对丰度降低、氮/氧化合物的缩合度增加、烷基侧链碳数范围降低,提出了多项氮、氧化合物的成熟度辅助识别指标,建立了DBE15/DBE9-N1和DBE15+/DBE14--N1与折算镜质体反射率之间的定量关系式。通过对氮、氧化合物的油-油、油-岩对比,认为东濮凹陷盐湖相原油主要来自成熟烃源岩。基于高分辨率质谱的氮、氧化合物具有重要的成熟度评价、油源对比、油气运移示踪的应用前景。 相似文献
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《Geofísica Internacional》2014,53(2):183-198
As a result of a gasoline spill in an urban area, Electrical Resistivity Tomography (ERT), Electromagnetic Profiling (EMP) and Volatile Organic Compounds (VOC) methods were used in order to define the contamination plume and to optimize the drilling and soil sampling activities. The VOC anomalies (recent contamination) indicated that a gas station located at the study site is an active contamination source. The mature contaminated zones defined by ERT and EMP methods corresponded with low resistivity anomalies due to degradation process of the hydrocarbons contaminants. The ERT, EMP and VOC results were integrated on a map, allowing the final configuration of contamination plumes and the optimization of drilling and soil/free-product sampling. Laboratory analyses of free-product samples suggest the existence of more than one contamination event in the site, with the presence of recent and degraded-hydrocarbon contaminants classified in the gasoline range. This study shows the advantages of joint application of ERT, EMP and VOC methods in sites with active contamination source, where the existence of recent and mature contaminants in subsoil is assumed. 相似文献
385.
Li-Peng Zhang Xin-Hong Wang Miao-Lei Ya Yu-Ling Wu Yong-Yu Li Zu-lin Zhang 《Marine pollution bulletin》2014
The occurrence of estrogens in the aquatic environment has become a major concern worldwide because of their strong endocrine disrupting potency. In this study, concentrations of four estrogenic compounds, estrone (E1), 17β-estradiol (E2), 17α-ethynylestradiol (EE2), estriol (E3) were determined with liquid chromatography-tandem mass spectrometry analyses in surface water from South China Sea, and distributions and potential risks of their estrogenic activity were assessed. The estrogenic compounds E1, E2 and E3 were detected in most of the samples, with their concentrations up to 11.16, 3.71 and 21.63 ng L−1. However, EE2 was only detected in 3 samples. Causality analysis, EEQ values from chemical analysis identified E2 as the main responsible compounds. Based on the EEQ values in the surface water, high estrogenic risks were in the coastal water, and low estrogenic risks in the open sea. 相似文献
386.
LU Hong SHI Quan MA QingLin SHI Yang LIU JinZhong SHENG GuoYing PENG PingAn 《中国科学:地球科学(英文版)》2014,(6)
Routine GC/MS analysis may apply to the volatilized Low-Molecular-Weight compounds in saturate and aromatic hydrocarbon fractions;thus,relative studies using this technique inevitably bring about some limitations on distribution of miscellaneous sulfur atom.In this article,Fourier Transform Ion Cyclotron Resonance Mass Spectrometry(FT-ICR MS)with high resolution is employed to investigate the distribution of organic sulfur compounds(OSCs)in the crude oil typically derived from the Eogene carbonate-evaporite sediments with further chemical compositional characterization in molecular level by miscellaneous atomic type,carbon number,and double bond equivalent(DBE).A variety of miscellaneous atomic types with S1,S2,S3,OS,OS2,O2S,O2S2,NS,and NOS etc.(S1 means those OSCs with one sulfur atom in a molecule)were identified in OSCs in these oil samples.High levels of alkyl thioether series compounds with one ring structure were presented mainly in the crude oil in the Jianghan Basin whereas high amounts of benzothiophene,dibenzothiophene etc.compounds with higher values in DBE and carbon number range occurred in the sulfur-rich heavy oil in the Jinxian Sag.Although carbonate-evaporite sediments deposited in the saline lacustrine facies in the Eogene basin both occurred in the Jinxian Sag and Jianghan Basin,obviously,they possess different chemical diagenetic pathway of sulfur under various microbial reactions,leading to diverse distributional characteristics on biomarkers,OSCs,and even different hydrocarbon generation mechanism of immature crude oil. 相似文献
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Ferrisilicalite‐1 Zeolite Monolith‐Based Affinitive Recognition of Intracellular Phosphorylated Protein Alteration in Tetrahymena thermophila Exposed to Photodegradates of Roxarsone and p‐Arsanilic Acid
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Wenzhong Zhang Fang Xu Jingjing Han Jun Yao Deju Wang Kai Yang Ceng Zeng Pengyuan Yang 《洁净——土壤、空气、水》2014,42(12):1798-1807
390.
Harbour porpoises are one of the three cetacean species inhabiting the Black Sea. This is the first study to report on polybrominated diphenyl ethers (PBDEs) and naturally-produced compounds, methoxylated PBDEs (MeO-PBDEs) and polybrominated hexahydroxanthene derivatives (PBHDs), in tissues (kidney, brain, blubber, liver, muscle) of male harbour porpoises (11 adults, 9 juveniles) from the Black Sea. Lipid-normalized concentrations decreased from muscle > blubber > liver > kidney > brain for the sum of polychlorinated biphenyls (PCBs) and for the sum of PBDEs. Among the naturally-produced compounds, levels of PBHDs were higher than of MeO-PBDEs, with tri-BHD and 6-MeO-BDE 47 being the dominant compounds for both groups, respectively. Concentrations of naturally-produced compounds decreased from blubber to brain, similarly to the sum of DDT and metabolites (DDXs). Concentrations of DDXs were highest, followed by PCBs, HCB, PBHDs, PBDEs and MeO-PBDEs. Levels of PCBs and PBDEs in blubber were lower than concentrations reported for harbour porpoises from the North Sea, while concentrations of DDXs were higher. 相似文献