饮用水含氮消毒副产物NDMA控制技术研究进展

N-亚硝基二甲胺（NDMA）作为一种新发现的饮用水消毒副产物,由于其具有高致癌风险,已逐渐成为水环境化学研究领域的一个热点。本文介绍了饮用水含氮消毒副产物NDMA的相关背景,分析了光降解、生物降解、臭氧氧化、高级氧化技术、吸附法、反渗透膜法及金属催化等各种NDMA去除工艺,探讨了各种工艺的特点以及对NDMA的去除性能。     

饮用水中二甲基亚硝胺的快速分析法

采用高效液相色谱仪,对饮用水及饮料中的二甲基亚硝胺进行检测,灵敏度高,重现性好,是准确,快速,简便的分析方法。     

室内环境污染对孕妇的危害

室内环境污染对人类健康的危害已受到全世界科学家们的广泛关注．近年来研究发现．这种污染给孕妇带来严重影响。室内微小环境是指建筑物内部由于围护结构（墙、屋板、地板、门窗等）的作用，形成的与室外不同的室内环境、它由气温、湿度、气流和辐射4项因素组成。据国外测定．室内空气污染最严重的地方依次为：厨房、酒。巴、咖啡厅、办公室。与此同时·被动吸烟对孕妇的危害不能忽视。众所周知．烟草烟雾中含有多种有害物质。例如：尼古丁、一氧化碳、焦油、亚硝胺等。经常工作生活在烟雾弥漫环境中的孕妇．由于长期被动吸烟．可影响胎儿…     

环境保护部发布六项环境保护标准

正7月26日,环境保护部发布《水质亚硝胺类化合物的测定气相色谱法》等六项标准为国家环境保护标准。标准名称、编号如下:一、《水质亚硝胺类化合物的测定气相色谱法》(HJ 809—2016);二、《水质挥发性有机物的测定顶空/气相色谱-质谱法》(HJ 810—2016);三、《水质总硒的测定3,3′-二氨基联苯胺分光光度法》(HJ 811-2016);     

有机胺类碳捕集药剂降解产物亚硝胺的健康风险评价

针对烟气CO_2捕集药剂的筛选主要集中在药剂成本、药剂对CO_2的吸收、解析性能、碳捕集技术的再生能耗等方面,忽略了药剂在重复连续使用过程中的降解以及降解产物的环境安全性这一情况,对365t/d的CO_2捕集工况进行了一乙醇胺(MEA)降解产物亚硝胺的大气扩散及健康风险分析。为完善碳捕集的安全性评价体系提供理论支持。     

MBR技术在石化污水处理中的应用

膜生物反应器(MBR)作为当前一项热门的水处理技术,在污水资源化领域已经显示了它的巨大潜力。文章介绍了MBR的发展概况、工艺特点以及在石化污水处理中的应用,并提出了应用中所存在的问题,对MBR工艺在石化系统中的应用研究方向进行了探讨。     

浅谈SCADA系统在污水处理厂中的应用

SCADA（数据采集与监视控制）系统是目前绝大多数污水处理厂实现现代化管理的控制技术,本文以已投入运营的珠海拱北污水处理厂为例,论述了SCADA技术在污水处理厂中的应用。     

空间数据挖掘的应用技术

空间数据挖掘技术是数据挖掘技术与空间数据库技术的融合,在GIS遥感、图像数据库、医疗影像处理等领域具有广阔的应用前景。基于空间数据挖掘的特点,论述了其在GIS中的应用,指出了空间数据挖掘面临的问题,并阐述了空间数据挖掘的发展趋势。     

黑龙江省煤炭资源开发中生态环境价值损失分析与测算

黑龙江省在煤炭资源开发过程中,对矿区的生态环境造成了巨大的破坏.针对黑龙江省四大煤城煤炭资源开采的生态环境损失问题,运用CVM法进行问卷调查收集数据,采用数据挖掘的方法分析了被调查者的属性与其支付意愿、支付额的关联关系,并进一步采用Tobit模型测算了四大煤城由于煤炭开采造成的生态环境价值损失.     

浅析珠三角地区有机废气治理技术的开发应用

珠江三角洲地区大气污染最明显的特点就是臭氧浓度的升高导致大气氧化性增强,而挥发性有机化合物(VOCs)和氮氧化物是大气臭氧生成的重要前体物。珠三角地区工业体系发达,VOCs的生产及使用企业众多,由于VOCs的种类繁多,性质各异,排放条件多样,目前已经形成了一系列的VOCs废气实用治理技术。     

Loss pathways of N-nitrosodimethylamine (NDMA) in turfgrass soils

N-nitrosodimethylamine (NDMA) is a potent carcinogen that is often present in municipal wastewater effluents. In a previous field study, it was observed that NDMA did not leach through turfgrass soils following 4 mo of intensive irrigation with NDMA-containing wastewater effluent. To better understand the loss pathways for NDMA in landscape irrigation systems, a mass balance approach was employed using in situ lysimeters treated with 14C-NDMA. When the lysimeters were subjected to irrigation and field conditions after NDMA application, very rapid dissipation of NDMA was observed for both types of soil used in the field plots. After only 4 h, total 14C activity in the lysimeters decreased to 19.1 to 26.1% of the applied amount, and less than 1% of the activity was detected below the 20-cm depth. Analysis of plant materials showed that less than 3% of the applied 14C was incorporated into the plants, suggesting only a minor role for plant uptake in removing NDMA from the vegetated soils. The rapid dissipation and limited downward movement of NDMA in the in situ lysimeters was consistent with the negligible leaching observed in the field study, and suggests volatilization as the only significant loss pathway. This conclusion was further corroborated by rapid NDMA volatilization found from water or a thin layer of soil under laboratory conditions. In a laboratory incubation experiment, prolonged wastewater irrigation did not result in enhanced NDMA degradation in the soil. Therefore, although NDMA may be present at relatively high levels in treated wastewater, gaseous diffusion and volatilization in unsaturated soils may effectively impede significant leaching of NDMA, minimizing the potential for ground water contamination from irrigation with treated wastewater.     

Leaching of N-nitrosodimethylamine (NDMA) in turfgrass soils during wastewater irrigation

N-nitrosodimethylamine (NDMA) is a carcinogenic by-product of chlorination that is frequently found in municipal wastewater effluent. NDMA is miscible in water and negligibly adsorbed to soil, and therefore may pose a threat to ground water when treated wastewater is used for landscape irrigation. A field study was performed in the summer months under arid Southern California weather conditions to evaluate the leaching potential of NDMA in turfgrass soils during wastewater irrigation. Wastewater was used to irrigate multiple turfgrass plots at 110 to 160% evapotranspiration rate for about 4 mo, and leachate was continuously collected and analyzed for NDMA. The treated wastewater contained relatively high levels of NDMA (114-1820 ng L(-1); mean 930 ng L(-1)). NDMA was detected infrequently in the leachate regardless of the soil type or irrigation schedule. At a method detection limit of 2 ng L(-1), NDMA was only detected in 9 out of 400 leachate samples and when it was detected, the NDMA concentration was less than 5 ng L(-1). NDMA was relatively persistent in the turfgrass soils during laboratory incubation, indicating that mechanisms other than biotransformation, likely volatilization and/or plant uptake, contributed to the rapid dissipation. Under conditions typical of turfgrass irrigation with wastewater effluent it is unlikely that NDMA will contaminate ground water.     

Degradation of N-nitrosodimethylamine (NDMA) in landscape soils

N-nitrosodimethylamine (NDMA), a potential carcinogen, was commonly found in treated wastewater as a by-product of chlorination. As treated water is increasingly used for landscape irrigation, there is an imperative need to understand the leaching risk for NDMA in landscape soils. In this study, adsorption and incubation experiments were conducted using landscape soils planted with turfgrass, ground cover, and trees. Adsorption of NDMA was negligibly weak (K(d) < 1) in all soils, indicating that NDMA has a high potential for moving with percolating water in these soils. Degradation of NDMA occurred at different rates among these soils. At 21 degrees C, the half-life (t(1/2)) of NDMA was 4.1 d for the ground cover soil, 5.6 d for the turfgrass soil, and 22.5 d for the tree soil. The persistence was substantially prolonged after autoclaving or when incubated at 10 degrees C. The rate of degradation was not significantly affected by the initial NDMA concentration or addition of organic and inorganic nutrient sources. The relative persistence was inversely correlated with soil organic matter content, soil microbial biomass, and soil dehydrogenase activity, suggesting the importance of microorganisms in NDMA degradation in these soils. These results suggest that the behavior of NDMA depends closely on the vegetation cover in a landscape system, and prolonged persistence and increased leaching may be expected in soils with sparse vegetation due to low organic matter content and limited microbial activity.     

纳滤膜去除内分泌干扰物/医药化合物研究进展

如何有效去除水中内分泌干扰物、医药活性化合物等有机微污染物的研究逐渐增加,其中,纳滤膜由于其较高的去除率得到了广泛关注。但由于纳滤膜去除这些物质的分离机理较为复杂,有时并不明确,给实验带来较大困难。文章总结了纳滤膜去除水中内分泌干扰物/医药活性化合物的典型应用及其三种分离机理——筛分作用、电荷作用、吸附作用,并对去除过程中所产生的问题和解决方案加以总结。为今后纳滤膜去除内分泌干扰物/医药活性化合物的研究提供参考依据。     

电器防雷滤波技术探讨

我国是雷电多发地区,在我们日常生活中电器经常会被雷电击坏或不能正常工作。本文就产品设计中我们常采用的一种既防雷又解决滤波的防雷滤波技术讨论,并加以验证。     

农业清洁生产技术应用的补偿机制实证研究——以云南省大理州洱源县农户调查为例

以云南省大理州洱源县农户调查为例,开展农户对于农业清洁生产技术采纳的补偿意愿实证研究。研究采用意愿价值评估法,在假设政府提供补偿的前提下进行农户问卷调查,获得农户对于采用不同农业清洁技术的受偿意愿数据,从而为制定相应的补偿政策提供依据。首先,分析了农户对于使用配方肥、秸秆还田及修建化粪池等3类清洁技术的采纳意愿;其次,明确了农户愿意接受的现金和实物2种补偿方式;第三,简单估算了农户采纳3类清洁技术希望获得的补偿标准;最后,调查了农户对于政府可能采取的推进清洁技术发展的配套政策的偏好程度。     

低温等离子体技术净化室内VOCs的研究进展

低温等离子体技术作为一种新型室内净化技术,能够有效降解室内挥发性有机化合物（VOCs）。本文首先简要介绍了室内VOCs的主要来源和对人体的危害,以及传统治理技术的不足,详细分析了低温等离子体净化VOCs的优势和机理,并对低温等离子净化VOCs存在的问题以及研究现状做了引证阐述,最后提出了有待解决的难题。     

不同浓度硒处理对彩叶草铅胁迫的EDXS和XRD分析

以彩叶草（ColeusblumeiBenth．）为材料,用营养液培养方法,研究了不同浓度硒（se）处理对浓度为1．0mmol·L-1Pb2＋胁迫下彩叶草根、叶的形貌变化及其组分形态等变化,从光谱学角度初步探讨了硒对重金属铅毒害的缓解机制。结果表明：铅胁迫下的彩叶草根系c、K、ca含量减少,O、Mg、Al、Si、Fe、Pb含量增加,叶片中的C、Mg、Al、si、K、Ca、Fe含量减少,O、Cl含量增加。铅胁迫下硒处理的彩叶草根元素种类及其元素含量均发生了明显变化;根中晶体情况及其晶相也发生了相应变化。     

±500kV直流复合绝缘子沿串积污特性研究

复合绝缘子的积污特性与瓷绝缘子和玻璃绝缘子有所不同,研究其积污规律对防止污闪有着重要意义。为此,以3支实际运行后的±500kV直流复合绝缘子为研究对象,系统测量其沿串不同位置的污秽度,用等值盐密(ESDD)和灰密(NSDD)表征。试验发现绝缘子不同伞上下表面的等值盐密和灰密大多呈现出U形的分布规律,尤其以等值盐密的U形分布更为明显,而且不同伞上下表面污秽U形分布规律性的强弱有一定差异。讨论了积污过程中电场对污秽沉积的作用以及自清洗过程中雨水冲洗的随机作用,更好地解释了直流复合绝缘子的沿串积污规律。