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直接进样-热脱附-GC-MS快速测定大气细颗粒物中有机示踪物 总被引:1,自引:0,他引:1
建立了直接进样-热脱附-GC-MS快速测定细颗粒物中甾烷类和藿烷类有机示踪物的方法。经实验条件优化,13种目标化合物的线性回归方程的相关系数均在0.990以上,空白加标回收率为81.4%~102.3%,实际样品加标回收率为79.1%~112.9%,相对标准偏差小于13.2%。当采样体积为24 m~3时,各目标化合物的检出限为0.008~0.084 ng/m~3,方法灵敏度高。利用该方法测定了北京城区采暖季和非采暖季PM2.5实际样品,结果表明:各目标物均有检出,且采暖季的甾烷类和藿烷类化合物的总量均明显高于非采暖季。该方法无需复杂的前处理和有机溶剂,操作简便快捷,在颗粒物中非极性化合物的快速检测方面具有很大的应用价值。 相似文献
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Antić MP Jovancićević BS Ilić M Vrvić MM Schwarzbauer J 《Environmental science and pollution research international》2006,13(5):320-327
Background, Aims and Scope It is well known that the composition of petroleum or some of its processing products changes in the environment mostly under
the influence of microorganisms. A series of experiments was conducted in order to define the optimum conditions for an efficient
biodegradation of petroleum pollutant, or bioremediation of different segments of the environment. The aim of these investigations
was to show to what extent the hydrocarbons of a petroleum pollutant are degraded by microbial cultures which were isolated
as dominant microorganisms from a surface water of a wastewater canal of an oil refinery and a nitrogen plant. Biodegradation
experiments were conducted on one paraffinic, and one naphthenic type of petroleum during a three month period under aerobic
conditions, varying the following parameters: Inorganic (Kp) or an organic medium (Bh) with or without exposition to light.
Methods Microorganisms were analyzed in a surface water sample from a canal (Pančevo, Serbia), into which wastewater from an oil
refinery and a nitrogen plant is released. The consortia of microorganisms were isolated from the water sample (most abundant
species: Phormidium foveolarum - filamentous Cyanobacteria, blue-green algae and Achanthes minutissima, diatoms, algae). The
simulation experiments of biodegradation were conducted with the biomass suspension and crude oils Sirakovo (Sir, paraffinic
type) and Velebit (Ve, naphthenic type). After a three month period, organic substance was extracted by means of chloroform.
In the extracts, the content of saturated hydrocarbons, aromatic hydrocarbons, alcohols and fatty acids was determined (the
group composition). n-Alkanes and isoprenoid aliphatic alkanes, pristane and phytane, in the aliphatic fractions, were analyzed
using gas chromatography (GC). Total isoprenoid aliphatic alkanes and polycyclic alkanes of sterane and triterpane types were
analyzed by GC-MS.
Results and discussion. Paraffinic type petroleums have a significant loss of saturated hydrocarbons. For naphthenic type petroleum,
such a trend has not been observed. The most intensive degradation of n-alkanes and isoprenoid aliphatic alkanes (in paraffinic
oil) and isoprenoids (in naphthenic oil) was observed using the inorganic medium Kp in the light; the microbial conversion
is somewhat lower with Kp in the dark; with organic medium Bh in the light the degradation is of low intensity; with the same
medium in the dark the degradation is hardly to be seen. Steranes and triterpanes were not affected by microbial degradation
under the conditions used in our experiments. Obviously, the petroleum biodegradation was restricted to the acyclic aliphatics
(n-alkanes and isoprenoids).
Conclusion Phormidium foveolarum (filamentous Cyanobacteria - blue-green algae) and Achanthes minutissima (diatoms, algae), microbial
cultures isolated as dominant algae from a surface water in a wastewater canal of an oil refinery and a nitrogen plant, have
degradable effects dominantly involving petroleum hydocarbons. Petroleum microbiological degradation is more intensive when
inorganic medium (in the light) is applied. Having in mind that the inorganic pollutants have been released into the canal
as well, this medium reflects more the natural environmental conditions. Polycyclic alkanes of sterane and triterpane type,
in spite of the fact that these compounds could be degraded, have remained unchanged regarding abundance and distribution.
Since this is the case even for naphthenic type petroleum (which is depleted in n-alkanes), it can be concluded that the biodegradation
of petroleum type pollutants, under natural conditions, will be restrained to the n-alkane and isoprenoid degradation.
Recommendation and Outlook Performed experiments and simulations of petroleum microbiological degradation may serve for the prediction of the fate of
petroleum type pollutants, as well as for definition of conditions for bioremediation of some environmental segments. 相似文献
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甾烷作为溢油指示物(或指标)的研究 总被引:9,自引:2,他引:9
为寻求重度风化溢油来源指标 ,依据有机地球化学相关研究成果 ,本文选定分子量大、水溶性小、抗风化的甾烷作为重度风化溢油的指示物 (或指标 )。将辽河原油等 15种原油作为研究对象 ,进行室内和室外模拟风化试验 ,用毛细管GC MS对不同环境 (海水、淡水、沙土等 )中风化 1a后的溢油进行检测。结果发现 ,油种间甾烷及其比值参数差异较大 ,在 1a的风化过程中受风化影响较小 ,可以作为重度风化溢油的指示物 (或指标 )。 相似文献
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Jovandićević B Antić MP Solević TM Vrvić MM Kronimus A Schwarzbauer J 《Environmental science and pollution research international》2005,12(4):205-212
Background, Aims and Scope In oil spill investigations, one of the most important steps is a proper choice of approaches that imply an investigation
of samples taken from different sedimentary environments, samples of oil contaminants taken in different periods of time and
samples taken at different distances from the oil spill. In all these cases, conclusion on the influence of the environment,
microorganisms or migration on the oil contaminants' composition can be drawn from the comparison of chemical compositions
of the investigated contaminants. However, in case of water contaminants, it is very important to define which part of organic
matter has been analyzed. Namely, previous investigations showed that there were some differences in chemical composition
of the same oil contaminant depending on the intensity of its contact with ground water. The aim of this work is to define
more precisely the interactions between oil contaminant and water, i.e. the influence of the intensity of interaction between
the oil contaminant and water on its chemical composition. The study was based on a comparison of four fractionated extracts
of an oil pollutant, after they had been analyzed in details.
Methods Oil polluted surface water (wastewater canal, Pančevo, Serbia) was investigated. The study was based on a comparison of four
extracts of an oil contaminant: extract 1 (decanted part), and extracts 2, 3 and 4 (extracted by shaking for 1 minute, 5 minutes
and 24 hours, respectively). The fractionated extracts were saponified with a solution of KOH in methanol, and neutralized
with 10% hydrochloric acid. The products were dissolved in a mixture of dichloromethane and hexane, and individually fractionated
by column chromatography on alumina and silica gel (saturated hydrocarbon, aromatic, alcohol and fatty acid fractions). n-Alkanes
and isoprenoid aliphatic alkanes, polycyclic alkanes of sterane and triterpane types, alcohols and fatty acids were analyzed
using gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). δ13CPDB values of individual n-alkanes in
the aliphatic fractions were determined using gas chromatography-isotope ratio monitoring-mass spectrometry (GC-irmMS).
Results and discussion. Extracts 1 and 2 are characterized by uniform distribution of n-alkanes, whereas extract 3 is characterized
by an even-numbered members dominating the odd-ones, and extract 4 showed a bimodal distribution. Extract 1 is characterized
by the least negative δ13CPDB values of C19-C26 n-alkanes. Sterane and triterpane analysis confirmed that all extracts originated
from the same oil contaminant. n-Fatty acids, C19-C24, in all extracts are very low, being somewhat higher in extract 4. Even-numbered
n-alcohols, C12–C16, were identified in the highest concentration in extract 3. It was assumed that algae were responsible
for the composition of extract 3. Furthermore, a possible reason for higher concentrations of C19–C26 n-alkanes and C19–C24
fatty acids in extract 4 is the formation of inclusion compounds with colloidal micelles formed between the oil contaminant's
NSO-compounds and water.
Conclusion It was undoubtedly confirmed that there were specific differences in the compositions of the different extracts depending
on the intensity of the interaction between the oil contaminant and the surface water.
Recommendation and Outlook. When comparing the composition of oil contaminants from different water samples (regardless of
the ultimate investigation goal) it is necessary to compare the extracts isolated under the same conditions, in other words,
extracts that were in the same or very similar interaction with water. 相似文献
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