Publications by authors named "Guan-Wen Cheng"

The passivation effect of FeO/mulberry pole biochar (Fe-MBC) prepared at different carbonization temperatures on soil available arsenic content was studied through soil culture experiments, and Fe-MBC-800 (prepared by carbonization at 800℃) with good passivation effect was selected and characterized. The effects of 1%-7% (mass fraction of biochar to soil) Fe-MBC-800, MBC-800, and FeO on soil pH value, soil electrical conductivity, soil arsenic form, rice biomass, and total arsenic (As) content in rice were studied using a pot experiment. The results showed that:①Fe-MBC-800 successfully loaded FeO, and its main functional groups were C=O double bond, O-H bond, C-O bond, and Fe-O bond.

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In this study, original mulberry-biochar (M-BC) and magnetic iron oxide/mulberry stem biochar (Fe-BC) materials were prepared and characterized using mulberry stems as the raw material. The effects of carbonized temperature of Fe-BC and M-BC on dissolved organic carbon (DOC) and arsenic(As) speciation in soil leaching solutions were studied using soil incubation experiments. The results showed that:① Fe-BC was mainly composed of FeO and was magnetic, and the main functional groups were a C=O double bond, O-H bond, C-O bond, and Fe-O bond.

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A lot of high-strength ammonia nitrogen wastewater is generated in the ion-type rare-earth elements hydrometallurgical process. Magnesium ammonium phosphate (MAP) precipitation was chosen to remove the ammonia nitrogen from the wastewater after Ca2+ was eliminated using Na2CO3 to generate CaCO3 precipitate, because the wastewater contained a lot of Ca2+, and Ca2+ was an important impact factor for MAP precipitation. Central composite design (CCD) is a principal response surface methodology (RSM) used in experimental design.

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This work presents a review of the microdialysis (MD) sampling technique for on-line coupling with high-performance liquid chromatography (HPLC) for biomedical analysis. MD-HPLC was first used in the field of brain metabolism to study neurotransmission, and this remains its common application in the biomedical field. On-line MD-HPLC hyphenated methods provide advantages over those with off-line MD-based techniques, including simplified sample preparation, automated analyses, avoidance of contamination introduced during the analytical process, and in situ analysis of the extracellular fluid of living organisms.

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We have developed a system that couples an on-line microdialysis (MD) system with flow injection high-performance liquid chromatography (HPLC)-fluorescence detection for simultaneous measurement of the concentrations of malondialdehyde (MDA) and ofloxacin (OFL) in whole blood samples. The sample matrix was first cleaned with an MD system using an MD probe. A continuously flowing dialysate stream was derivatized on-line and auto-injected into a separation column.

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An on-line configuration of microdialysis (MD), Au/TiO2 nanoparticle preconcentration, and high-performance liquid chromatography-ultraviolet (HPLC-UV) detection method was developed for the simultaneous measurement of cobalt (Co) and nickel (Ni) concentrations in water. The sample matrix was first cleaned with an MD system using a MD probe. A continuously flowing dialysate stream was introduced into tubing coated with Au/TiO2 nanoparticles to adsorb metals, followed by elution by an acidic eluent.

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This study establishes the applicability of using high-performance liquid chromatography (HPLC) with fluorescence detection for the simultaneous determination of malondialdehyde (MDA) and ofloxacin (OFL). The MDA and OFL were separated through a reverse-phase C18 column (250 mm x 4.6 mm) at a flow rate of 1.

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Although manganese (Mn) is an essential element, exposure to excessive levels of Mn and its accumulation in the brain can cause neurotoxicity and extrapyramidal syndrome. We have investigated the differences in the accumulated levels of Mn, the degree of lipid peroxidation, and its effects on the levels of trace elements (Fe, Cu, and Zn) in various regions in the brain of rats having undergone acute Mn exposure. The rats in the dose-effect group were injected intraperitoneally (ip) with MnCl2 (25, 50, or 100 mg MnCl2/kg ) once a day for 24 h.

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