Penetration of polar brominated DBPs through the activated carbon columns during total organic bromine analysis

Total organic bromine (TOBr) is a collective parameter representing all the brominated organic disinfection byproducts (DBPs) in water samples. TOBr can be measured using the adsorption-pyrolysis method according to Standard Method 5320B. This method involves that brominated organic DBPs are separated from inorganic halides and concentrated from aqueous solution by adsorption onto the activated carbon (AC). Previous studies have reported that some commonly known brominated DBPs can partially penetrate through the AC during this adsorption step. In this work, the penetration of polar brominated DBPs through AC and ozone-modified AC was explored with two simulated drinking water samples and one chlorinated wastewater effluent sample. Polar brominated DBPs were selectively detected with a novel precursor ion scan method using electrospray ionization-triple quadrupole mass spectrometry. The results show that 3.4% and 10.4% of polar brominated DBPs (in terms of total ion intensity) in the chlorinated Suwannee River fulvic acid and humic acid samples, respectively, penetrated through the AC, and 19.6% of polar brominated DBPs in the chlorinated secondary wastewater effluent sample penetrated through the AC. The ozone-modification of AC minimized the penetration of polar brominated DBPs during the TOBr analysis.     

Distribution and source of microplastics in China's second largest reservoir - Danjiangkou Reservoir

Fresh water microplastic pollution is of pressing concern globally, but its distribution and sources in reservoirs are poorly documented. Danjiangkou Reservoir is the second largest reservoir in China and is divided into the Han Reservoir and Dan Reservoir. In this work, microplastic abundances and morphological characteristics of the reservoir were investigated. The microplastic abundance of 15 main tributaries of the reservoir was also measured. The vertical distribution (in water column and sediment), horizontal distribution (in Han Reservoir and Dan Reservoir) and source of microplastics were analyzed. Microplastics accumulated in the middle layer of the reservoir, and the size and color of the microplastic particles changed from the surface to the bottom, which implies that surveys of surface water are not enough to determine the microplastic contamination for deep water reservoirs. In the surface water, the microplastic abundance in the Han Reservoir was lower than that in the Dan Reservoir (p < 0.05), but microplastic abundance did not differ significantly in the intermediate and bottom water. Tributaries were one of the main sources of microplastics for Han Reservoir but not for Dan Reservoir. Agricultural cultivation in the hydro-fluctuation belt might be an important source of microplastics in the Dan Reservoir, which should be given additional attention. The results of this study can provide valuable information for developing microplastic sampling strategies in deep water reservoirs. Further studies are recommended to investigate the process through which microplastics in the hydro-fluctuation belt enter the reservoir and the sinking behavior of microplastics in the reservoir.     

镉污染土壤淋洗剂研究进展

随着工农业的发展,土壤重金属污染问题日益突出,土壤污染治理已成为农业和环境等相关领域的研究热点。以土壤重金属污染中最严重的镉污染治理为研究目标,以化学淋洗剂为研究对象,综合评述了不同类型淋洗剂的洗脱机理、淋洗效果和影响因素,推荐了适用于不同镉污染土壤的淋洗剂,并对现阶段国内外镉污染土壤淋洗剂研究中存在的问题和研究方向进行了总结和展望。研究认为土壤镉污染复合淋洗技术的机理研究,淋洗技术的示范和推广,适用低渗透土壤的淋洗剂研发,淋洗下土壤及环境的变化研究,淋洗剂投放后土壤修复的数值模拟研究,低成本、高效率生物表面活性剂、螯合剂、土壤缓冲剂的开发,以及开展多学科的交叉融合研究等是未来镉污染土壤淋洗技术研究的主要方向。     

High performance of multi-layered alternating Ni–Fe–P and Co–P films for hydrogen evolution

Judiciously engineering the electrocatalysts is attractive and challenging to exploit materials with high electrocatalytic performance for hydrogen evolution reaction. Herein, we successfully perform the interface engineering by alternately depositing Co–P and Ni–Fe–P films on nickel foam, via facile electroless plating and de-alloying process. This work shows that there is a significant effect of de-alloying process on alloy growth. The electronic structure of layered alloys is improved by interface engineering. The multilayer strategy significantly promotes the charge transfer. Importantly, the Co–P/Ni–Fe–P/NF electrode fabricated by interface engineering exhibits excellent electrocatalytic hydrogen evolution activity with an overpotential of 43.4 mV at 10 mA cm-2 and long-term durability for 72 h in alkaline medium (1 mol L-1 KOH). The innovative strategy of this work may aid further development of commercial electrocatalysts.     

Synergistic effects of gaseous pollutants on hospital admissions for cardiovascular disease in Liuzhou,China

Previous studies demonstrated that short-term exposure to gaseous pollutants (nitrogen dioxide (NO₂), sulfur dioxide (SO₂), and ozone (O₃)) had a greater adverse effect on cardiovascular disease. However, little evidence exists regarding the synergy between gaseous pollutants and cardiovascular disease (CVD). Therefore, we aimed to estimate the effect of individual gaseous pollutants on hospital admissions for CVD and to explore the possible synergistic effects between gaseous pollutants. Daily hospitalization counts for CVD were collected from January 1, 2014, to December 31, 2015. We also collected daily time series on gaseous pollutants from the Environment of the People’s Republic of China, including NO₂, SO₂, and O₃. We used distributed lag nonlinear models (DLNMs) to assess the association of individual gaseous pollutants on CVD hospitalization, after controlling for seasonality, day of the week, public holidays, and weather variables. Then, we explored the variability across age and sex groups. In addition, we analyzed the synergistic effects between gaseous pollutants on CVD. Extremely low NO₂ and SO₂ increase the risk of CVD in all subgroup at lag 7 days. The greatest effect of high concentration of SO₂ was observed in male and the elderly (≥ 65 years) at lag 3 days. Greater effects of high concentration of O₃ were more pronounced in the young (< 65 years) and female at lag 3 days, while the effect of low concentration of O₃ was greater in male and the young (< 65 years) at lag 0 day. We found a synergistic effect between NO₂ and SO₂ for CVD, as well as between SO₂ and O₃. The synergistic effects of NO₂ and SO₂ on CVD were stronger in the elderly (≥ 65) and female. The female was sensitive to synergistic effects of SO₂-O₃ and NO₂-O₃. Interestingly, we found that there was a risk of CVD in the susceptible population even for gaseous pollutant concentrations below the National Environmental Quality Standard. The synergy between NO₂ and SO₂ was significantly associated with cardiovascular disease hospitalization in the elderly (≥ 65). This study provides evidence for the synergistic effect of gaseous pollutants on hospital admissions for cardiovascular disease.

     

基于臭氧-麸皮工艺深度处理煤制气废水的研究

以河南省某化工企业生产过程中煤制气废水为研究对象,通过絮凝、臭氧-麸皮协同催化氧化、A/O生化处理的组合工艺改善废水的可生化性,能显著降低煤制气废水中的污染物浓度,COD由2 800 mg/L降至46 mg/L,氨氮质量浓度降至2.1 mg/L,总酚去除率达到99%,整个流程简单易操作,不产生二次污染,且能实现麸皮的高价值利用,达到GB 8978—1996的一级排放标准。     

Heavy metal distribution in soils near Palapye, Botswana: an evaluation of the environmental impact of coal mining and combustion on soils in a semi-arid region

Morupule Colliery near Palapye in eastern Botswana is the only coalmine in production in Botswana at present. Its coal is mainly used in the nearby coal-fired Morupule Power Station, which generates approximately 1,000 GWh of electricity per annum. After more than 30 years mining and more than 20 years of combustion, the sedimentation of outlet fly ash from the Morupule Power Station has increased concentrations of Cr, Ni, Zn and As by 13, 2.5, 16 and 5 ppm, respectively, in the fine portion (<53 μm) of surface soils for approximately 9 km downwind. Elements that have higher concentrations in coal have stronger small-particle association during coal combustion and are less mobile in surface soils, thus showing stronger contaminations in surface soils around the coal-fired plant. Although the degree of contamination of Cr, Ni, Zn and As from coal combustion in the Palapye area at present is low, it is necessary to monitor concentrations of these elements in surface soils routinely in the future. This study also reveals moderate Pb and Zn contaminations in the Palapye area. The former is due to the use of leaded petroleum in motor vehicle traffic and the latter is mainly due to the use of galvanized iron sheets in construction.     

有机微污染源水生物预处理微生物菌种的分离筛选

以黄浦江为被处理源水 ,分别从染料化工厂二级生化处理厂和生活污水处理厂取得活性污泥 ,经驯化、分离 ,以对源水中TOC降解率为主要指标筛选得到 9个菌种 ,分别编号为 TD1～ 9.经测试这 9株菌对源水中 20 mg/L的 TOC具有 50 %左右的去除率 ;经初步分类鉴定 ,其中菌 TD1为芽孢杆菌属 ,TD2、3、7、8为放线菌目 ,TD4、5、6、9为假单胞菌属 .     

环境监测在环保工作中的作用

为提升环保工作效果,促进环保工作高效、有序开展,指出了环境监测在环保工作中的重要作用:进一步明确环保工作方向,为环保工作开展提供科学数据支持,提高环境质量评价的准确性.分析了环境监测在水污染防治、大气污染防治、土壤污染防治中的具体实践,提出提高环境监测质量的措施:及时解决环境监测中发现的问题,强化对环境监测数据的分析和...     

农田土壤温室气体产生机制及影响因素研究进展

农田土壤通过微生物呼吸、植物根系呼吸和土壤动物呼吸,释放大量温室气体,成为大气中主要温室气体(CO2、CH4和N2O)的重要来源.文章在阐述土壤温室气体产生机制的基础上,着重从土壤生物、土壤理化性质(主要包括温湿度、有机质、pH、Eh、土壤质地等)、水肥管理及耕作措施等角度对农田土壤温室气体释放的影响进行了综述,对土壤温室气体的减排措施进行了总结,并就今后农田土壤温室气体的研究重点和方向进行了展望.