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A comprehensive wet chemical procedure was developed by combining acid demineralization, base extraction, and dichromate oxidation for fractionation and quantitative isolation of soil/sediment organic matter (SOM) into four fractions: (1) humic acids + kerogen + BC (HKB); (2) kerogen + BC (KB); (3) humic acid (HA); and (4) BC. The soil/sediment samples(More)
This paper reports the sorption of two male hormones, testosterone and androstenedione, by four soil and sediment samples at both equilibrium and rate-limiting conditions. Unlike prior studies, androstenedione was studied independently of testosterone. Apparent sorption equilibrium is achieved in one to two weeks when the initial aqueous hormone(More)
The Xijiang River is the major tributary of the Pearl River, South China, and is the major source water system for more than 4.5 million of urban population and 28.7 million of rural population. We initiated a systematic study on detection and quantification of organic pollutants in both water and suspended particulate matter (SPM) for samples collected in(More)
Distinctly different rates and pathways were observed for abiotic transformation of gamma-hexachlorocyclohexane (gamma-HCH) between homogeneous systems and systems containing FeS solid. The observed half-lives of gamma-HCH decrease from about 1136 and 126 d in homogeneous systems to about 55 and 50 d in heterogeneous systems at pH approximately 6.9 and pH(More)
This study reported detection of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) for 62 soil samples and 3 sediment samples collected from the Pearl River Delta, a rapidly industrialized and highly populated area of South China. The results show that the PCDD/F concentrations ranged from 97.6 to 9,600 ng kg(-1) and that the average total(More)
This study investigated the rates and pathways of gamma-hexachlorocyclohexane (gamma-HCH) dechlorination by granular zero-valent iron under different pH, iron dosage and temperature conditions. It was found that gamma-HCH was rapidly reduced to benzene and chlorobenzene (CB) with benzene as the major product and that the dechlorination likely follows three(More)
Numerous studies have reported a spectrum of sorption phenomena in soils, sediments, and organic matter isolates of those materials that are inconsistent with a partition model proposed in the late 1970s and early 1980s, a model predicated on a hypothesis that sorption is linear and noncompetitive. To explain these nonideal phenomena, prior studies have(More)
The first paper of this series reported that soil/sediment organic matter (SOM) can be fractionated into four fractions with a combined wet chemical procedure and that kerogen and black carbon (BC) are major SOM components in soil/sediment samples collected from the industrialized suburban areas of Guangzhou, China. The goal of this study was to determine(More)
Anaerobic aniline biodegradation was investigated under different electron-accepting conditions using contaminated canal and groundwater aquifer sediments from an industrial site. Aniline loss was observed in nitrate- and sulfate-amended microcosms and in microcosms established to promote methanogenic conditions. Lag times of 37 days (sulfate amended) to(More)
This study investigated the effect of chemical heterogeneity of humic acids (HAs) on the equilibrium sorption of phenanthrene by HA extracts. Six HA samples were extracted from three different soils with 0.5 M NaOH and 0.1 M Na4P2O7 and were characterized with elemental analysis, infrared spectrometry, and solid-state 13C nuclear magnetic resonance (NMR)(More)