含泥沙的地表水总氮测定准确度的提高方法

针对碱性过硫酸钾消解紫外分光光度法测定含泥沙的地表水中总氮时,数据准确度常受到絮凝沉淀的干扰的问题,采用一次性0.45μm水相针式滤器过滤消解后水样,快速有效地去除絮凝沉淀的干扰,达到了提高含泥沙的地表水总氮测定准确度的目的。结果表明,该方法相对标准偏差2.0%,加标回收率为92.0%~96.5%,符合实验室质控要求。     

水中氨氮测定前处理的改进

地表水中氨氮测定的前处理多采用絮凝沉淀-滤纸过滤法。由于滤纸常含微量铵盐 ,因此要反复用纯水和水样清洗除去 ,增加了操作复杂性。另外 ,有时会遇到絮凝物呈胶体状而产生过滤困难 ,增加了操作时间。经实践 ,在絮凝沉淀后 ,改用离心沉淀法除去絮凝沉淀物 ,不仅能缩短前处理时间 ,而且可避免沾污的发生。水中氨氮测定前处理的改进@戴建红$泰兴市环境监测站!江苏　泰兴　225400     

一种新的絮凝沉淀实验的数据处理法

通过分析现有絮凝沉淀实验的数据处理方法，指出了其存在的不足。并提出了其改进后的新方法     

离心法应用于高浊度地表水中氨氮测定预处理过程中的方法

比较多种预处理方法去除浊度对地表水氨氮测定的影响,结果表明在测定高浊度地表水氨氮的过程中,采用离心法可较好地去除悬浮物对水样测定的干扰。较清水样用比色前离心方法,对于较浑浊的水样用絮凝沉淀结合比色前离心方法,可明显去除浊度的干扰,得到稳定的氨氮数值。2种方法的准确度和精密度均满足质控要求。     

酚二磺酸法测定地表水中NO_3—N方法的改进

1.样品预处理当Cl~-含量超过10mg.L时,对测定结果产生干扰.在去除Cl~-时,对有些水质样品来说,成分复杂,干扰因素较多,使AgCl的沉淀效果不好.即按“方法”操作,加入Ag_2SO_4后,无论放置过夜或80℃加热絮凝,然后过滤,结果均不理想.经试验加入大量Al(OH)_3使之共沉淀(每100ml水样加Al(OH)_3悬浮液20ml),结果比较好,显色也正常(黄色透明).不过,由此将导致样品体积增大(稀释),最后在测定结果中以相应的稀释倍数即可扣除其影响.     

紫外-可见分光光度法用于染料废水絮凝脱色效果测定的研究

染料废水絮凝处理后的脱色率是检验絮凝剂絮凝效果的重要指标。文章通过测定废水絮凝处理前后吸光度值的变化 ,从而精确计算出脱色率 ,可避免传统目视比色法带来的人为误差。采用分光光度法测定染料废水絮凝脱色率 ,方法简单、易掌握     

高藻含量水体中BOD_5监测方法探讨

分析了高藻含量水体中BOD5偏高产生的主要原因,是由于藻类光合作用使水中溶解氧大幅增高引起的.并进一步通过实验,验证了对于高藻含量水体中BOD5的监测,采用硫酸铝絮凝沉淀、离心分离后测定,可消除藻类干扰的有效性.     

扣除基体空白值在比色测定地下水中氨氮时的应用

测定水中的氨氮常采用纳氏试剂光度法。此法操作简便、灵敏度高,但新疆地区水中的钙、镁和铁等金属离子、硫化物、颜色及悬浊物等均干扰测定。对于有颜色或浑浊的水样,常用絮凝沉淀过滤或蒸馏法预处理,以消除干扰。但通常遇到的外观较清洁的水样,分析时往往不经任何预处理就直接加试剂测定。这通常不能保证分析质量,由下述实验说明。     

水样氨氮测试预处理方法的改进

水样氨氮测试预处理方法的改进何睦贤（浙江省建德市环境监测站，建德３１１６００）改用沉淀后分离，效果大为改善。具体操作：取１００ｍｌ水样置１２５ｍｌ梨形分液漏斗中，加１ｍｌ１０％硫酸锌溶液，边遥边滴加２５％氢氧化钠溶液至絮凝沉淀开始（ｐＨ７２０～７?..     

测定水中氨氮预处理絮凝剂的改进

通常测定水中氨氮时 ,以Ｚｎ(ＯＨ) 2 为絮凝沉淀剂 ,沉淀速度快 ,但分层不清 ,上层液中呈白色混浊。以Ａｌ(ＯＨ) 3为沉淀剂时 ,则试剂配制麻烦。今采用两者混合物 ,发现预处理效果较好。混合物的配制方法 :称取 7ｇＡｌ2 (ＳＯ4) 3·1 8Ｈ2 Ｏ和 1 3ｇＺｎＳＯ4·7Ｈ2 Ｏ ,溶于 80ｍＬ水中。使用时 ,取水样 1 0 0ｍＬ于量筒中 ,加上述混合物 0 5ｍＬ ,混匀 ,再加 50 0 ｇ/ＬＮａＯＨ溶液 2滴～ 3滴 ,混匀 ,静置 1 0ｍｉｎ ,吸取上清液测定。当发现不易絮凝下沉时 ,可适当提高Ａｌ2 (ＳＯ4) 3的比例。测定水中氨氮预处理絮凝剂的改进@吴景…     

Estimating the Ecological Condition of the Estuaries of the Gulf of Mexico

Monitoring of estuaries in the Louisianian Province was performed annually from 1991–1994 to assess ecological conditions on a regional scale. We found over the four years of monitoring, 25±6% of Gulf of Mexico estuarine sediments in the Louisianian Province displayed poor biological conditions, as measured by benthic community structure, and 14±7% of the area was characterized by poor water clarity, the presence of marine debris, and elevated levels of fish tissue contaminants. Using statistical associations to discern relationships between ecological condition and exposure or stressor data has shown that much of this degraded' condition co-occurs with sediment contamination.     

装潢居室空气中甲醛采样方法改进

对空气中甲醛测定的采样方法进行了探讨 ,分别用水和稀硫酸作吸收液对空气甲醛进行采样研究。结果表明 ,用 0 .0 0 5mol LH2 SO4 作吸收液的采样方法 ,可有效、稳定地延长样品的保存时间 ,且又符合方法灵敏度和精密度的要求。     

Environmental Assessment of the Impact of Ozone to the Neuston of the Sea-Surface Microlayer of the Gulf of Mexico

Substantial amounts of NOx (146 000 t/y) and total hydrocarbons (294 000 t/y) are released to the marine atmosphere by the large number of oil and gas operations over Federal waters of the Gulf of Mexico (GOM). Under appropriate meteorological conditions these emissions react to form ozone (0–54 g/m3 over-water) which can affect the marine environment. Using a dry deposition model, this work examines the amount of ozone derived from oil and gas offshore operations and deposited in the sea surface of the Gulf of Mexico, and assesses its impact on the neuston of the sea-surface microlayer. Surface integrated estimates of ozone deposited from oil and gas operations over the sea surface ranges from 400 kg to 1800 kg which results in sea surface concentrations of 15 g/m3. This estimate and the actual toxic ozone levels suggest no acute, toxic impacts to the neuston. However, indirect effects may occur through changes to the pelagic foodwebs and organic carbon pathways. Another potential pathway for ozone impacting the environment is through the production of bromate. Based on the concentrations and time scales (11–139 days) only sublethal effects appear to occur, but uncertainties associated with this assessment need to be further studied. From an ecological perspective, the environmental impacts and risks of NOx and VOC discharges from offshore platforms need to be assessed for neuston and other components of the marine ecosystem.     

泰东河疏浚工程对通榆河水质的影响

为了解泰东河疏浚工程对通榆河水质的影响,于2012年6月8日、9月12日、12月6日,对泰东河沿线以及通榆河东台段进行调查取样,分析施工期间河体水质变化。结果表明,施工期间水质参数基本保持在Ⅱ~Ⅲ类。根据江苏省水环境监测中心盐城分中心2011年、2013年监测资料评价分析,泰东河河道疏浚后,清理了河床淤泥,提高了泰东河的行洪、抗洪以及通航能力,其水质的好转有效地改善了下游通榆河的水质,确保了饮水安全。     

State of the Estuaries in the Mid-Atlantic Region of the United States

The U.S. EPA has prepared a State of the Region Report for Mid-Atlantic Estuaries to increase knowledge of environmental condition for improved environmental management. Sources of information included the National Estuary Programs, the Chesapeake Bay Program, the state monitoring programs in Delaware, Maryland, and Virginia, Federal programs such as National Status & Trends, National Shellfish Register, National Wetlands Inventory, the Environmental Monitoring and Assessment Program, and other primary literature sources. The state of the estuarine environment was summarized using indicators for water and sediment quality, habitat change, condition of living resources, and aesthetic quality. Each indicator was briefly discussed relative to its importance in understanding estuarine condition. Wherever possible, data from multiple programs were used to depict condition. Finally, an overall evaluation of estuarine condition in the region was determined. The usefulness of monitoring programs that collect consistent information with a well-defined sampling design cannot be overemphasized.     

锅炉污染物监测中运行负荷的现场判断

简述了锅炉的风量和烟气量、锅炉燃料的消耗量以及锅炉运行负荷的估算方法。通过实例分析,用现场监测的实际风量与理论值比较,粗略估算出监测时段锅炉运行负荷,比对锅炉污染物监测时段的锅炉运行负荷标准,从而判断监测数据的准确性与有效性。     

环境监控(监测)建设与发展过程的思考

论述环境监控系统的发展过程、具体应用和建设的意义。叙述环境监控系统的建设为解决环境质量监测、污染源在线自动监测和生态监测与具体部门相关联而造成信息孤岛的问题,提倡环保多业务综合共享信息的标准化;环境监控系统的建设是基础,应用是关键,运行维护管理是保障,三者不可偏废。让环境管理者产生形象思维,拓宽思路和视野,发现和解决新问题。     

能见度分级约束下的大气气溶胶光学厚度特征

利用ＰＩＳ太阳光谱仪观测了北京地区１９９３年３月—１９９５年３月晴天和少云天气的太阳直接辐射光谱，波长范围为０．４０－１．０４μｍ。光谱分辨率１．２５ｎｍ，共有１０６４组数据。观测期间，将地面能见度分为五级。由太阳直射谱获得了各能见度下大气气溶胶光学厚度谱。研究表明，北京地区大气气溶胶光学厚度虽然其总体季节统计规律为春夏大，秋冬小，然而，当加入能见度分级约束后，各能见度下气溶胶光学厚度的季节变化，近于消失。这表明少数“反常”垂直结构不影响能见度分级的平均结果。而不分级的光学厚度季节起伏主要由各季节的几率能见度决定。文中还把年平均五种能见度下的光谱光学厚度与ＬＯＷＴＲＡＮ模式作了对比。由光学厚度谱反演出了气溶胶粒子谱分布，为建立我国北方局地气溶胶模式构造了基本框架     

Studies of the effect of simulated acid rain on the ecological equilibrium of the soil system

Introduction to the problem of environmental pollution caused by acid depositions. Presentation of principles of the six-year field experiment with simulated acid rain. Short characteristics of particular parts of the series of papers.     

长江上游合江江段鱼类早期资源与向家坝水库生态调度效果初步研究

合江江段是长江上游干流保持河流生境、适宜喜流水性鱼类栖息的重要江段.为了掌握合江江段鱼类早期资源动态,分析向家坝水库生态调度的效果,于2020年向家坝水库生态调度前后,开展了鱼类早期资源逐日监测.研究期间,共采集到鱼类早期资源5目10科38种(属),其中仔鱼29种(属)、鱼卵19种(属),包括特有鱼类6种.广适应性和喜...