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241.
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In many metropolitan regions, natural sources contribute a substantial fraction of volatile organic compound (VOC) emissions.
These biogenic VOC emissions are precursors to tropospheric Ozone (O3) formation. Because forests make up 59% of the land area in Taiwan Province, China, the biogenic VOC emissions from forests
and farmland could play an important role in photochemical reactions. On the other hand, anthropogenic emissions might also
be one of the major inputs for ground level O3 concentrations. Hence, emission inventory data, grouped as point, area, mobile and biogenic VOC sources, are a composite
of reported and estimated pollutant emission information and are used by many air quality models to simulate ground level
O3 concentrations. Before using relevant air quality models, the emission inventory data generally require huge amounts of processing
for spatial, temporal, and species congruence with respect to the associated air quality modeling work. The fist part of this
research applied satellite remote sensing and geographic information system (GIS) analyses to characterize land use/land cover
(LULC) patterns, integrating various sources of anthropogenic emissions and biogenic emissions associated with a variety of
plant species. To investigate the significance of biogenic VOC emissions on ozone formation, meteorological and air quality
modeling were then employed to generate hourly ozone estimates for a case study of a high ozone episode in southern Taiwan,
which is the leading industrial hub on the island. To enhance the modeling accuracy, a unique software module, SMOKE, was
set up for emission processing to prepare emission inputs for the U.S. EPA’s Models-3/CMAQ. An emission inventory of Taiwan,
TEDS 4.2, was used as the anthropogenic emission inventory. Biogenic emission modeling was accomplished by BEIS-2 in SMOKE,
with improvement of local LULC data and revised emission factors. Research findings show that the majority of biogenic VOC
emissions occur in the mountainous areas and farmlands. However, the modeling outputs show that downwind of the most heavily
populated and industrialized areas, these biogenic VOC emissions have less impact on air quality than do anthropogenic emissions. 相似文献
243.
辽河西部凹陷油气十分富集,油气藏类型复杂,油气相态多样发育,不同构造带油气运移特征存在差异。本文主要根据原油中咔唑类含氮化合物浓度和相关参数,以及储层流体包裹体的发育特征,结合油气相态及物性分布特征,探讨了辽河西部凹陷油气运移特征以及影响因素。研究表明,中央隆起带原油中咔唑类化合物浓度高、异构化参数变化小,油气包裹体主要呈线状分布,在切穿矿物加大边的裂隙中,油气运移通道以走滑形成的东西向雁列式或帚状断裂为主,运移动力主要为流体异常压力;斜坡带原油中咔唑类化合物浓度及其相关异构化参数变化明显,油气包裹体多分布在石英与长石颗粒次生加大边中,呈群体面状分布,显示较强荧光特征,油气主要由洼陷带至斜坡带以扇三角洲前缘分支河道指状砂体或辫状河道砂体为运移通道,以水动力与浮力推动,远源或近源运移成藏;陡坡带原油中咔唑类化合物总浓度以及异构化参数存在变化,以台安大洼断裂带或指状砂体为运移通道、以异常流体压力为动力近源运移成藏;古潜山原油咔唑类化合物总浓度低,参数变化明显,主要以不整合面或基底断裂为运移通道,以异常流体压力为动力近源运移成藏。油气运移聚集时间主要在东营期,自北往南油气成藏时间逐渐变晚,与沙三段、沙四段生烃期较为匹配。 相似文献
244.
How to use the groundwater resources at the area polluted by organoarsenic compounds for Old Japanese Army Toxic Gas Weapon in Japan
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从医学地质学角度看,在日本地质污染的地方如何使用地下水资源,我们面临许多问题.本文讨论了地质污染学(geo-pollution science)作为医学地质学中一门学科的概念以及在受二苯亚砷酸污染的地方成功使用农业地下水的案例. 相似文献
245.
The acidic and neutral NSO compounds in a series of Duvernay-sourced oils in Canada, which are believed to have migrated extensively over relatively long distances such as along the Rimbey-Meadowbrook reef trends, were characterized by negative-ion electrospray (ESI) Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). Heteroatomic compounds were characterized according to their class (number of nitrogen, oxygen and sulfur heteroatoms), degree of aromaticity [rings plus double bonds (DBE)] and carbon number distribution. The N1, N1O1, N1O2, N1S1, O1 and O2 classes were identified in Duvernay-sourced oils. With increasing migration distance, the relative abundance of O2, N1O1 and N1O2 showed a significant decrease, while the O1 class increased from < 10% to nearly 30% of the total. With increasing migration along the Rimbey-Meadowbrook reef trend, pyrrolic nitrogen compounds (N1 class) shows an enrichment of alkylcarbazoles (DBE = 9) relative to alkylbenzocarbazoles (DBE = 12), and of higher homologous relative to the lower homologous. O1 compounds show a relative enrichment of those with low DBE values. Additionally, the N1O1 and N1S1 compounds show a relative enrichment of those with high DBE values, and of higher homologues compared to the lower homologues, indicating great potential for developing new migration indices. 相似文献
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248.
Ronghui Zheng Chao Fang Fukun Hong Weiming Kuang Yulu Jiang Jincan Chen Yusheng Zhang Jun Bo 《海洋学报(英文版)》2022,41(12):105-114
Polycyclic aromatic hydrocarbons (PAHs) pollution, particularly in coastal environments, is a global concern. In this study, the biomonitoring and ranking effects of PAHs in the rockfish Sebastiscus marmoratus were determined in the Maowei Sea, China. The results showed that the concentrations of the 16 priority PAHs detected in the surface seawater were moderate compared with those in other coastal areas worldwide, and the possible sources were rapid industrialization and urbanization combined with atmospheric deposition and runoff. Nested analysis of variance (ANOVA) suggested significant differences in the hepatic ethoxyresorufin-O-deethylase (EROD) activities and phenanthrene-derived metabolites in bile between the port area and the oyster farming area. The fish expert system (FES) was applied to evaluate the biological effects of PAHs on fish. The FES data demonstrated that the biological effect levels of Site S1 (level III, medium stress) were higher than those of the other sampling sites (level II, low stress). 相似文献
249.
WANG Chao TAO Renbiao Jesse B. WALTERS REN Tianshi NAN Jingbo ZHANG Lifei 《《地质学报》英文版》2023,97(1):288-308
The geologic production of abiotic organic compounds has been the subject of increasing scientific attention due to their use in the global carbon flux balance, by chemosynthetic biological communities, and for energy resources. Extensive analysis of methane(CH4) and other organics in diverse geologic settings, combined with thermodynamic modelings and laboratory simulations, have yielded insights into the distribution of specific abiotic organic molecules on Earth and the favorable c... 相似文献
250.