Publications by authors named "Zhixi Dai"

Microplastic (MP) pollution has become a global concern, and the transport behavior of MPs in soil-water systems is vital in determining their distribution and potential risks to the subsurface environment. To reveal the role of various soil components on MP migration, the downward transport behavior of polystyrene (PS) MPs were explored in this study via column experiments with mono or multi-soil components as porous media. Compared with the selected soil mineral volcanic rock (VR) and fine river sand (RS), condensed soil organic matter (SOM) resulted in higher transport efficiencies for PS microparticles, with greater than 90% total mass recovery under the experimental conditions.

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Biofortification of crops with exogenous iodine is a novel strategy to control iodine deficiency disorders (IDD). The bioaccessibility of iodine (BI) in the biofortified vegetables in the course of soaking, cooking and digestion, were examined. Under hydroponics, the concentration of iodine in leafstalks of the celery and pakchoi increased with increasing exogenous iodine concentration, 54.

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This research demonstrated a new method, simultaneous derivatization and ultrasound assisted emulsification microextraction combined with gas chromatography-flame ionization detector (SD-USAEME-GC-FID), for the determination of anilines in environmental water samples. In this study, several factors, such as the volume of butylchloroformate (as derivatization agent/ extraction solvent), ultrasonication time, solution pH, salt addition, and centrifuging time and speed, were optimized in order to obtain good method performance. As a result, under the optimal conditions, the method showed good linearity in the concentration range of 6-60 000 μg x L(-1) with correlation coefficients (R2) ranging from 0.

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The release of hydrogen sulfide (H2S) during sludge drying is a major environmental problem because of its toxicity to human health. A series of experiments were performed to investigate the mechanisms and factors controlling the H2S release. Results of this study show that: (1) the biomass and activity of sulfate-reducing bacteria (SRB) in sludge were the major factors controlling the amount of H2S release, (2) the sludge drying temperature had an important effect on both the extent and the timing of H2S release from the sludge, and (3) decreasing sludge pH increased the H2S release.

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