Environmental quality and its impact on the local economy: A case study from Dongguan,South China

Industries that pollute the environment developed in the early 1990s in Dongguan City, especially those in the middle and lower valley of the Dongjiang River (waterside area) have seriously affected water and air quality and hence have affected soil quality through polluted water irrigation and precipitation. Investigation of the economic growth and environmental pollution in the 32 township units in the City from 1990 to 2000 also reveals that environmental pollution has affected the history of the development of the towns or townships in the waterside region in the delta of the River Dongjiang, especially the towns near the river mouth, and has prevented their industry from upgrading and hence has slowed down their economic growth. The impact of environmental pollution on economic growth is most severe in the towns along the lower valley, or in down-wind regions. In contrast, economic development in the protected area of the upper valley of the waterside region indicates that environmental protection that strictly controls the discharge of pollutants does not restrict the development of the local economy.     

不同类别农药助剂对蚯蚓(Eisenia foetida)的急性毒性

为评价农药助剂对土壤生物的毒性效应,分别采用滤纸接触法和人工土壤法测定了不同类别农药助剂对赤子爱胜蚓(Eisenia foetida)的急性毒性。结果表明：19种非离子表面活性剂中,烷基酚聚氧乙烯醚与脂肪醇聚氧乙烯醚毒性较高,滤纸法48 h-LC₅₀为7.630～39.65 μg·cm^-2,人工土壤法14 d-LC₅₀为876.5～2786.6 mg·kg^-1,其它类型非离子表面活性剂毒性较低。5种阴离子表面活性剂中,十二烷基硫酸钠、十二烷基苯磺酸钙毒性高于木质素磺酸钠、木质素磺酸钙、亚甲基双萘磺酸钠,滤纸法48 h-LC₅₀为6.575～41.89 μg·cm^-2,人工土壤法14 d-LC₅₀为1195.0～1911.7 mg·kg^-1。13种溶剂中,二甲苯、乙苯、甲苯、正丁醇、环己酮表现出较高的毒性,滤纸法48 h-LC₅₀为6.587～57.62 μg·cm^-2,密封人工土壤法48 h-LC₅₀为181.9～781.5 mg·kg^-1。采用两种方法测得的5种填料高岭土、白炭黑、硅藻土、凹凸棒土和轻质碳酸钙的毒性均较低。由此可见,采用两种方法测得的毒性系统偏差接近,重现性均较好,并且滤纸接触法测得的毒力高于人工土壤法。     

Inhibition of bromate formation by reduced graphene oxide supported cerium dioxide during ozonation of bromide-containing water

GO or RGO promotes bromate formation during ozonation of bromide-containing water. CeO₂/RGO significantly inhibits bromate formation compared to RGO during ozonation. CeO₂/RGO shows an enhancement on DEET degradation efficiency during ozonation. Ozone (O₃) is widely used in drinking water disinfection and wastewater treatment. However, when applied to bromide-containing water, ozone induces the formation of bromate, which is carcinogenic. Our previous study found that graphene oxide (GO) can enhance the degradation efficiency of micropollutants during ozonation. However, in this study, GO was found to promote bromate formation during ozonation of bromide-containing waters, with bromate yields from the O₃/GO process more than twice those obtained using ozone alone. The promoted bromate formation was attributed to increased hydroxyl radical production, as confirmed by the significant reduction (almost 75%) in bromate yield after adding t-butanol (TBA). Cerium oxide (less than 5 mg/L) supported on reduced GO (xCeO₂/RGO) significantly inhibited bromate formation during ozonation compared with reduced GO alone, and the optimal Ce atomic percentage (x) was determined to be 0.36%, achieving an inhibition rate of approximately 73%. Fourier transform infrared (FT-IR) spectra indicated the transformation of GO into RGO after hydrothermal treatment, and transmission electron microscope (TEM) results showed that CeO₂ nanoparticles were well dispersed on the RGO surface. The X-ray photoelectron spectroscopy (XPS) spectra results demonstrated that the Ce³⁺/Ce⁴⁺ ratio in xCeO₂/RGO was almost 3‒4 times higher than that in pure CeO₂, which might be attributed to the charge transfer effect from GO to CeO₂. Furthermore, Ce³⁺ on the xCeO₂/RGO surface could quench Br⋅ and BrO⋅ to further inhibit bromate formation. Meanwhile, 0.36CeO₂/RGO could also enhance the degradation efficiency of N,N-diethyl-m-toluamide (DEET) in synthetic and reclaimed water during ozonation.     

我国土壤环境的风险评估技术分析与展望

随着我国工业化、城镇化及农业高度集约化的快速发展,耕地和场地土壤复合污染问题日益突出,土壤污染的风险日趋显现.本文在总结国内外土壤污染健康风险评估技术发展历程的基础上,探讨我国国内建设用地健康风险评估技术导则的异同点,分析目前国内外有关土壤环境风险评估技术研究的热点与不足,重点介绍了蒸气入侵模型的发展、土壤中有机污染物...     

Application of proteomics in environmental science

Proteomics involves the separation of proteins, identification of the amino acid sequence of the interested or target proteins, study of the function of the proteins, modification, structure and ultimate assignments to functional pathways in the cell. The proteomic investigations have contributed greatly to human diseases studies, new drugs discovery researches, and environmental science in recent years. This article provides a review on the development of the main proteomic technologies, including both the gel based and non-gel based technologies, and their applications in environmental science. Proteomic technologies have been utilized in the environmental stresses studies to analyze the induction or reduction of proteins at expression level and identify the target proteins to investigate their function in response to environmental stresses, such as high or low pH, oxidation stress, and toxic chemicals. Such protein responses are also helpful to understand the mechanisms of some cellular activities and the functions of some proteins.     

土壤铜镉污染的电动力学修复实验

针对土壤典型重金属污染修复问题,通过实验方法研究了土壤铜镉污染的电动力学修复效果,并分析其迁移变化特征.实验结果表明,在电场作用下土壤中重金属的质量分数发生明显变化,使得大部分重金属能在电极附近富集而被去除,且土壤的pH值等是影响电动力学修复效果的重要因素.污染物Cd和Cu在电场作用下主要是在阴极附近产生富集,迁移方向由阳极向阴极,表明电场作用加强重金属Cd和Cu迁移效果.当实验电压为0.5 V/cm时,在阳极附近土壤中镉的去除效率为75.1%,铜的去除效率达到77.9%.另外,电动修复中由于阴阳两极的氧化还原反应造成电极附近pH值产生明显变化,其中阳极附近的pH值由开始时的7.5逐渐变小到4.7,而阴极附近则相反,由开始时的7.2逐渐增大到9.4,表明土壤的酸碱条件变化明显.     

两种生物农药对土壤蔗糖酶活性的影响

采集海南省儋州市国家热带农业高新技术示范园土样中农田土样,在分析土壤基本理化性质的基础上,用3,5-二硝基水杨酸比色法测定法.研究了不同模拟条件下苏云金杆菌、井冈霉素A对土壤蔗糖酶活性的影响.结果表明:不同浓度、pH条件下这两种生物农药对土壤蔗糖酶表现出不同程度的激活作用.在30 d的培养时间内,苏云金杆菌(bacillus thuringiensis)对土壤蔗糖酶活性影响的趋势是激活→抑制→恢复,而且波动范围较大;井岗霉素A(jinggangmycin A)对土壤蔗糖酶活性影响程度相对较小,总的趋势是激活→抑制.总体来看,施用这两种生物农药有利于提高土壤蔗糖酶的活性.     

含铬废水的治理研究

介绍了含铬废水的分离处理研究现状，讨论了各自的应用原理及优缺点。对工程设计和生产工艺提出了一些有益的建议。并对含铬废水处理的发展趋势作了分析和展望。     

空气微生物研究方法进展与展望

着重论述了空气微生物气溶胶的研究方法，主要有培养基法和非培养基法。培养基法是传统的微生物研究方法，需要花费大量的时间和劳动力，只能够检测活的能够在培养基上生长的微生物，可以大致反映空气中的微生物气溶胶。非培养基法，主要是PCR法，具有敏感性高、快速、特异性强等特点，能够检测出环境样品中绝大多数的微生物，是一种微生物气溶胶检测的有效途径。最后指出实时持续的监测是将来空气微生物研究的努力方向和发展趋势。     

多相催化-臭氧氧化法处理模拟有机磷农药废水

实验通过臭氧氧化法来降解模拟废水中的有机磷农药，将其转化为无害物质，并试验研究了在废水中加入2种自制的催化剂对降解结果的影响。采用气相色谱法测定水中有机磷农药的量。结果表明，只用臭氧处理的情况下1周后有机磷的去除率为78．03％；在催化剂A存在下，去除率可达93．85％；在催化剂B存在下，去除率可达为88．35％。结果表明，臭氧氧化法对此类污水：具有较好的降解作用，尤其在有催化剂存在的情况下处理效果更好，在室温和中性介质中均属于一级反应。