外源铅在不同类型土壤的形态转化

采用为期60 d的室内培养方法探究南方典型红壤和灰壤中添加高浓度外源铅后Pb稳定化过程。结果表明,加入高浓度外源铅后,土壤有效态Pb含量在培养期内呈现先降低后稳定的趋势,培养30 d后DTPA(二乙烯三胺五乙酸)-Pb浓度基本达到稳定平衡,土壤离子交换态Pb、碳酸盐结合态Pb含量明显降低,形态-BAC风险评价方法表明,供试土壤均能在自然条件下降低铅的生态风险危害,能为修复铅污染土壤工程应用提供科学依据。     

磷石膏窑外分解中试研究

以无烟煤为还原剂、添加3.5%矿化剂,在有效容积为0.25 m3的竖罐反应装置中对磷石膏进行了窑外分解中试研究。结果表明:随着反应温度的升高,磷石膏分解率逐渐增大;适宜的还原氛围有利于磷石膏的热分解进程;混合物料的碳硫比为0.75时,在950 ℃条件下磷石膏分解率最高可达90.6%,窑气中SO2体积分数约为8%。HSC热力学计算表明:生成中间产物CaS是硫酸钙热分解过程的必经阶段,鼓入适量空气是保证磷石膏热分解中间产物CaS较为彻底地转化为CaO与SO2的必要条件。     

Relationships of ozone formation sensitivity with precursors emissions, meteorology and land use types, in Guangdong-Hong Kong-Macao Greater Bay Area, China

Due to the influences of precursors emissions, meteorology, geography and other factors, ozone formation sensitivity(OFS) is generally spatially and temporally heterogeneous. This study characterized detailed spatial and temporal variations of OFS in Guangdong-Hong Kong-Macao Greater Bay Area(GBA) from 2012 to 2016 based on OMI satellite data, and analyzed the relationships of OFS with precursors emissions, meteorology and land use types(LUTs). From 2012 to 2016, the OFS tended to be NO x-limite...     

Urinary concentrations of phenols, oxidative stress biomarkers and thyroid cancer: Exploring associations and mediation effects

Phenols have been shown to influence the cellular proliferation and function of thyroid in experimental models. However, few human studies have investigated the association between phenol exposure and thyroid cancer, and the underlying mechanisms are also poorly understood. We conducted a case-control study by age- and sex-matching 143 thyroid cancer and 224 controls to investigate the associations between phenol exposures and the risk of thyroid cancer, and further to explore the mediating role of oxidative stress. We found that elevated urinary triclosan (TCS), bisphenol A (BPA) and bisphenol S (BPS) levels were associated with increased risk of thyroid cancer (all P for trends < 0.05), and the adjusted odds ratios (ORs) comparing the extreme exposure groups were 3.52 (95% confidence interval (CI): 2.08, 5.95), 2.06 (95% CI: 1.06, 3.97) and 7.15 (95% CI: 3.12, 16.40), respectively. Positive associations were also observed between urinary TCS, BPA and BPS and three oxidative stress biomarkers measured by 8-hydroxy-2′-deoxyguanosine (8-OHdG), 8-iso-prostaglandin F_2α (8-isoPGF_2α) and 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA), as well as between urinary 8-isoPGF_2α and HNE-MA and the risk of thyroid cancer. Mediation analysis showed that urinary 8-isoPGF_2α mediated 28.95%, 47.06% and 31.08% of the associations between TCS, BPA and BPS exposures and the risk of thyroid cancer, respectively (all P < 0.05). Our results suggest that exposure to TCS, BPA and BPS may be associated with increased risk of thyroid cancer and lipid peroxidation may be an intermediate mechanism. Further studies are warranted to confirm the findings.     

电增强载铝活性炭纤维吸附氟离子性能

以载铝活性炭纤维毡为电极,在电场作用条件下对模拟含氟水进行静态吸附实验。结果表明,该载铝活性炭纤维毡正极化可以强化吸附除氟效果,吸附动力学数据很好地符合Lagergren二级速率方程,加电场时二级反应速率常数为4.50 g/（mg·h）;其对高浓度含氟饮用水也有较高去除率,Freundlich吸附等温方程能很好地描述吸附平衡数据。加电场情况下,该载铝炭毡对氟离子的最大吸附量为16.584 mg/g,去除氟离子的最佳pH范围是5.5~8.9。共存阴离子Cl-、SO42-和NO3-对炭毡吸附除氟没有抑制作用,但CO32-的存在会导致除氟吸附量显著下降。     

Model-averaged confidence distributions

Environmental and Ecological Statistics - Model averaging is commonly used to allow for model uncertainty in parameter estimation. As well as providing a point estimate that is a natural compromise...     

A wetland plant,Phalaris arundinacea,accumulates nitrogen and phosphorus during senescence

Environmental Science and Pollution Research - Secondary pollution resulting from shoot death is a difficult problem that complicated the application of wetland plants for water purification in...     

Methane emissions responding to Azolla inoculation combined with midseason aeration and N fertilization in a double-rice cropping system

Environmental Science and Pollution Research - Methane (CH4) is an important greenhouse gas (GHG), and paddy fields are major sources of CH4 emissions. This pot experiment was conducted to...     

Enhanced nickel removal and synchronous bioelectricity generation based on substrate types in microbial fuel cell coupled with constructed wetland: performance and microbial response

Environmental Science and Pollution Research - In this study, an attempt was made to clarify the impact of substrates on the microbial fuel cell coupled with constructed wetland (CW-MFC) towards...     

Catalytic pyrolysis of Eupatorium adenophorum by sodium salt

Journal of Material Cycles and Waste Management - Eupatorium adenophorum (EA) has been spread widely in China and its increasing number has posed potential threats and damages to the ecosystem and...