Two complementary LC-MS ionization methods, electrospray (ESI) and atmospheric pressure photoionization (APPI), have been optimized to determine three natural estrogenic compounds (estrone, 17beta-estradiol and estriol) and two synthetic estrogenic compounds (17alpha-ethynylestradiol and diethylstilbestrol) in the influent and effluent of wastewater treatment plants (WWTPs). The wastewater samples were first subjected to solid-phase extraction coupled with desalting extraction to remove matrix interference. The analytes were then detected using liquid chromatography-tandem mass spectrometry (LC-MS-MS) with ESI and dopant-assisted (DA) APPI to evaluate the ion suppression effect and to complement the detection and quantification of estrogenic compounds in complex wastewater samples. The average ion suppression factors for the extracts of the WWTP influent analyzed using ESI and APPI were 52+/-5% and 27+/-7%, respectively. The sensitivity and ionization efficiency of the LC-ESI-MS-MS system decreased dramatically when a complex matrix was present in the WWTP influent sample. Estrogenic compounds could be detected in the WWTP influent and effluent samples at concentrations below the parts-per-billion level. The lower detection limits obtained when using ESI and the higher matrix tolerance of the APPI method allowed the complete quantification of estrogenic compounds in very complex samples in a complementary manner. 相似文献
Concentrations of 16 polycyclic aromatic hydrocarbons (PAHs) in soil, moss and reindeer dung collected at Ny-Ålesund of the Arctic were measured to investigate their accumulation trends and distribution in the three compartments. Compared with the other regions, the proportions of 2 + 3 ring PAHs to the total PAHs were higher, whereas the proportions of 5 + 6 ring PAHs were lower in the three compartments at Ny-Ålesund. Significant log/log-linear relationship was observed between the sub-cooled liquid vapor pressure and the soil/moss quotient (QSM). The relation was similar to the relationship between the gas/particle partition coefficient (KP) and of PAHs, implying QSM would be a “mirror image” of KP. Excellent log/log-linear relationships were observed between QSM and KOA as well as between the moss/dung quotient (QMD) and KOW. The results presented here indicate the physicochemical properties are suitable for characterizing the distribution of PAHs in soil, moss and reindeer dung. 相似文献
It is common that 2,4,6-trichlorophenol (TCP) coexists with nitrate or nitrite in industrial wastewaters. In this work, simultaneous reductive dechlorination of TCP and denitrification of nitrate or nitrite competed for electron donor, which led to their mutual inhibition. All inhibitions could be relieved to a certain degree by augmenting an organic electron donor, but the impact of the added electron donor was strongest for TCP. For simultaneous reduction of TCP together with nitrate, TCP’s removal rate value increased 75% and 150%, respectively, when added glucose was increased from 0.4 mmol?L–1 to 0.5 mmol?L–1 and to 0.76 mmol?L–1. For comparison, the removal rate for nitrate increased by only 25% and 114% for the same added glucose. The relationship between their initial biodegradation rates versus their initial concentrations could be represented well with the Monod model, which quantified their half-maximum-rate concentration (KS value), and KS values for TCP, nitrate, and nitrite were larger with simultaneous reduction than independent reduction. The increases in KS are further evidence that competition for the electron donor led to mutual inhibition. For bioremediation of wastewater containing TCP and oxidized nitrogen, both reduction reactions should proceed more rapidly if the oxidized nitrogen is nitrite instead of nitrate and if readily biodegradable electron acceptor is augmented.
To better understand the Hg(II) adsorption by some typical soils and explore the insights about the binding between Hg(II) and soils, a batch of adsorption and characteristic experiments was conducted. Results showed that Hg(II) adsorption was well fitted by the Langmuir and Freundlich. The maximum adsorption amount of cinnamon soil (2094.73 mg kg?1) was nearly tenfold as much as that of saline soil (229.49 mg kg?1). The specific adsorption of Hg(II) on four soil surface was confirmed by X-ray photoelectron spectroscopy (XPS) owing to the change of elemental bonding energy after adsorption. However, the specific adsorption is mainly derived from some substances in the soil. Fourier transform infrared spectroscopy (FTIR) demonstrated that multiple oxygen-containing functional groups (O–H, C=O, and C–O) were involved in the Hg(II) adsorption, and the content of oxygen functional groups determined the adsorption capacity of the soil. Meanwhile, scanning electron microscopy combined with X-ray energy dispersive spectrometer (SEM–EDS) more intuitive revealed the binding of mercury to organic matter, metal oxides, and clay minerals in the soil and fundamentally confirmed the results of XPS and FTIR to further elucidate adsorptive phenomena. The complexation with oxygen-containing functional groups and the precipitation with minerals were likely the primary mechanisms for Hg(II) adsorption on several typical soils. This study is critical in understanding the transportation of Hg(II) in different soils and discovering potential preventative measures. 相似文献
Environmental Science and Pollution Research - Feedback between hydrologic variations and chemical weathering is thought to play a crucial role in modulating global carbon cycling. The mechanisms... 相似文献
Environmental Science and Pollution Research - Microcystis aeruginosa (M. aeruginosa) is one of the most common genera of cyanobacteria in algal blooms. In the present work, the impact of the... 相似文献
Environmental Science and Pollution Research - Microbial fuel cell (MFC) is a sustainable technology to treat cattle manure slurry (CMS) for converting chemical energy to bioelectricity. In this... 相似文献