原子吸收法间接测定水中可溶性硫化物

原子吸收法间接测定水中可溶性硫化物汪凤麟（北京市环境监测中心，１０００４４）目前国内外有关硫化物的测定方法报道较多的仍以碘量法和对氨基二甲基苯胺比色法为主。碘量法是较为准确的测定方法，适用于测定１毫克／升以上浓度的硫化物，但由于工业废水成分复杂，干扰...     

用改进的凯氏法测定生物样品和水样中总氮方法的探讨

对凯氏法测定生物环境样品中总氮的测定方法进行了研究和改进，以简易装置代替凯氏消解装置，省略了蒸馏步骤。避免了称量时易造成的样品损失及蒸馏过程的氨氮损失。经过实际样品的测定，并与原测定方法进行了对比实验，证明改进后的测定方法具有准确度高，精密度好，实验装置及步骤简便易行的特点。缩短了实验周期，提高了氮的回收率。同时，用改进后的方法对水样进行了测定，也取得了良好效果。     

恶臭国标测定方法和便携式恶臭测定仪测定结果的比对分析

比对了恶臭国标测定方法《GB/T 14675—1993》和便携式恶臭测定仪对厂界环境空气无组织排放臭气浓度的测定结果。结果显示,恶臭国标测定方法和便携式恶臭测定仪的测定值基本在同一范围内,具有一定的可比性,但2种方法在嗅辨方式、工作地点、结果计算方式、配气方法、样品原始性和测定范围上都存在差异。     

废气中氮氧化物的测定方法NEDA——三乙醇胺法

废气中氮氧化物的测定方法ＮＥＤＡ──三乙醇胺法华雪萍（无锡环境科学研究所２１４０２３）废气中氮氧化物的测定方法，尚无统一标准，盐酸紫乙二胺法测定废气中的氮氧化物是国家环保局推荐的测定方法之一，此法在采样过程中使用的吸收液要避光，当烟气温度及环境温度较...     

COD快速测定方法的研究进展

针对于COD传统的标准测定方法所存在的各种不足，国内的科研工作者在仪器分析法测定COD方面做了大量的研究工作和改进，开发出了一系列的快速测定方法．本文主要对目前快速测定COD主要方法的研究进展进行了阐述．     

改进的还原偶氮光度法同时快速测定水中硝基苯和苯胺

对测定方法进行了改进,建立了用还原-偶氮分光光度法同时快速测定水中硝基苯和苯胺的分析方法。根据实验原理,对样品前处理装置进行了改进,实验步骤得到了简化,避免了样品溶液过滤转移过程造成样品损失,使样品前处理实验效率提高了90%以上;改进后的测定方法不仅可快速测定样品中硝基苯,还可同时测定样品中苯胺;达到了用一种分析方法同时测定样品中两种污染物的目的。方法精密度测定结果,相对标准偏差(n=6,RSD)为1.9%~3.2%;对硝基苯、苯胺混合标准样品以及实际废水样品进行了测定,并与原测定方法及苯胺国标测定方法进行了比对实验;测定结果具有一致性。加标实验回收率为96%~101%,表明方法准确可靠,可用于水和废水中硝基苯或硝基苯和苯胺的同时测定。     

河口水中矿物油分析的研究

紫外分光光度法在河口水中矿物油测定中，存在着标准油品的选择、水样萃取的乳化处理及河口水样测定方法选择等问题。提出了解决存在问题的可行方法，进一步完善测定方法。     

生化需氧量BOD_5测定影响因素

BOD5是对企业污水排放是否达标的一个很重要的水质指标,测定方法很多。我们结合实际工作讨论BOD5的测定方法及测定过程中的影响因素:稀释水、接种、水样的稀释倍数、溶液酸碱度、温度、溶解氧、毒害物质、硝化作用等。     

我国固体废物监测技术发展现状

简述了我国固体废物环境管理和监测框架体系,回顾了固体废物监测的发展历史,并从采样和制样、浸出毒性的浸出方法、无机污染物和有机污染物测定方法等方面对固体废物监测现状进行了总结。针对固体废物监测体系存在的问题,提出了对采样技术开展更新性研究,尽快将已有的测定方法标准化并建立总量监测方法,开发各类污染物的形态分析方法,以及规范废弃物危险特性试验方法等建议。     

生化需氧量(BOD)测定技术进展

综合评述了BOD5指标发展历程和测定方法,重点讨论了标准稀释法接种技术和微生物传感器方法研究的主要进展。     

Estimation of bacteriological levels in surface water samples to evaluate their contamination profile

The present work deals with the assessment of bacteriological contamination along with some physico-chemical parameters of water samples from Lahore canal. ANOVA showed that the observed p values of log-transformed viable plate counts, total suspended solids, turbidity, and biological oxygen demand are 0.000, 0.000, 0.000, and 0.000, respectively, which are <0.05, while the p value of total coliforms, total fecal coliforms, and Escherichia coli are 0.728, 0.827, and 0.081, respectively which are >0.05. Significant correlation was observed between log-transformed viable plate counts (CFU), biological oxygen demand, total suspended solids, and turbidity. Further regression analysis revealed that simple line regression model is fit for log-transformed viable plate counts and total suspended solids, log-transformed viable plate counts and turbidity, turbidity and total suspended solids, biological oxygen demand and total suspended solids, biological oxygen demand and log-transformed viable plate counts, and biological oxygen demand and turbidity.     

生化需氧量测定中若干因素探讨

介绍了生化需氧量的方法建立过程,指出测定生化需氧量时,除了温度对测定有影响外,pH值、无机盐类、微生物种类和数量、稀释度、硝化作用、缓冲剂,以及充分的营养和毒性物质的存在与否都会对测定结果有影响.     

Deficit analysis: service capacity assessment and planning in developing countries – case study in the Philippines

Current demand analysis methods do not formally cover the case of chronic deficits in quantity or quality of water and sanitation services. These services include drinking water supply (DWS), wastewater and sewage treatment (WST), and municipal solid waste management (MSW). Formal analysis of this case would, at minimum, define the deficit state and evaluate appropriate options for reducing it. This paper proposes for a formal analytical model for municipal sanitation systems (MSS) that operate with deficits in at least one of the constituent services of DWS, WST, or MSW. The model introduces definitions and notation for describing the deficit state for conducting demand analysis on municipal sanitation systems. This model of demand analysis for systems with chronic deficits will hereinafter be referred to as deficit analysis. A case study for Bacoor, Philippines is presented as an example.     

深圳市河流水质评价指标筛选方案探讨

通过计算各条河流的综合污染指数和各项水质指标的污染分担率,对深圳市8条主要河流1999—2008年水质监测数据进行分析,最终从15项常规水质指标中筛选出氨氮、总磷、生化需氧量、化学需氧量、高锰酸盐指数、石油类、挥发酚、硫化物和六价铬9项指标,建议作为深圳市河流水质评价的统一指标。     

Optimization of pressure gauge locations for water distribution systems using entropy theory

It is essential to select the optimal pressure gauge location for effective management and maintenance of water distribution systems. This study proposes an objective and quantified standard for selecting the optimal pressure gauge location by defining the pressure change at other nodes as a result of demand change at a specific node using entropy theory. Two cases are considered in terms of demand change: that in which demand at all nodes shows peak load by using a peak factor and that comprising the demand change of the normal distribution whose average is the base demand. The actual pressure change pattern is determined by using the emitter function of EPANET to reflect the pressure that changes practically at each node. The optimal pressure gauge location is determined by prioritizing the node that processes the largest amount of information it gives to (giving entropy) and receives from (receiving entropy) the whole system according to the entropy standard. The suggested model is applied to one virtual and one real pipe network, and the optimal pressure gauge location combination is calculated by implementing the sensitivity analysis based on the study results. These analysis results support the following two conclusions. Firstly, the installation priority of the pressure gauge in water distribution networks can be determined with a more objective standard through the entropy theory. Secondly, the model can be used as an efficient decision-making guide for gauge installation in water distribution systems.     

Using Resource Economics to Anticipate Forest Land Use Change in the U.S. Mid-Atlantic Region

Demands for forest, farm, and developed land are evolving in the U.S. mid-Atlantic region. The demand for land in developed uses, as well as demands for various forest and farm products are changing in response to population growth, demographic shifts, and market forces. As demand factors change so do relative land values. Land area in future forest, farm, and developed uses may shift as landowners re-evaluate relative net benefits from land use alternatives. This study examines the effects of various land demand and supply factors on the determination of land use patterns in the mid-Atlantic region. Driving variables include costs and benefits from various uses, population density, and measures of land quality. Model parameters are estimated using a binomial logit procedure. Results from the study are used to estimate proportions of forest area on a county by county basis. Simulated forest landscapes under hypothetical future conditions are prepared and illustrated using geographic information system (GIS) techniques.     

我国重大活动环境空气质量监测预报评估技术体系的发展与思考

通过总结南京青年奥林匹克运动会、二十国集团领导人峰会、金砖国家领导人第九次会晤、中国国际进口博览会、第七届世界军人运动会等重大活动环境空气质量保障工作经验,简述近年来中国重大活动环境空气质量监测预报评估技术的进展以及所发挥的作用。结合城市环境精细化管控和未来我国"十四五"环境空气质量持续改进的需求,提出在监测网络、监测技术、排放清单、预测预报产品和保障机制等方面有待提升的建议。     

Analysis of the environmental impact on a stream: is only tannery to blame?

The contribution of wastewater from a tannery industry to the pollution of a stream was investigated. The main parameters studied were biochemical oxygen demand, chemical oxygen demand, chromium, dissolved oxygen, fecal and total coliforms, nitrogen, oils and greases, pH, phosphorous, sulfides, suspended solids, turbidity, and volatile solids. Three sampling points were located: (1) at the discharge point of tannery wastewater, (2) 50 m upstream, and (3) 80 m downstream of discharge point. Also was investigated the pollution at the stream source.     

Environmental water demand assessment under climate change conditions

Measures taken to cope with the possible effects of climate change on water resources management are key for the successful adaptation to such change. This work assesses the environmental water demand of the Karkheh river in the reach comprising Karkheh dam to the Hoor-al-Azim wetland, Iran, under climate change during the period 2010–2059. The assessment of the environmental demand applies (1) representative concentration pathways (RCPs) and (2) downscaling methods. The first phase of this work projects temperature and rainfall in the period 2010–2059 under three RCPs and with two downscaling methods. Thus, six climatic scenarios are generated. The results showed that temperature and rainfall average would increase in the range of 1.7–5.2 and 1.9–9.2%, respectively. Subsequently, flows corresponding to the six different climatic scenarios are simulated with the unit hydrographs and component flows from rainfall, evaporation, and stream flow data (IHACRES) rainfall-runoff model and are input to the Karkheh reservoir. The simulation results indicated increases of 0.9–7.7% in the average flow under the six simulation scenarios during the period of analysis. The second phase of this paper’s methodology determines the monthly minimum environmental water demands of the Karkheh river associated with the six simulation scenarios using a hydrological method. The determined environmental demands are compared with historical ones. The results show that the temporal variation of monthly environmental demand would change under climate change conditions. Furthermore, some climatic scenarios project environmental water demand larger than and some of them project less than the baseline one.     

Influence of different textile fibers on characterization of dyeing wastewater and final effluent

Textile industry needs to recover and reuse its wastewater as to fulfil the demand of increasingly strict regulations. The characterization of dyeing wastewater samples according to textile fiber and final textile effluent enables the application of different treatment methods. This study aims to characterize dyeing wastewater in black color of polyamide, polyester, and viscose fibers and final textile effluent. Samples were collected and characterized completely for major pollution indicator parameters. Dyeing wastewater of polyester showed higher values for some parameters, e.g., 4994.44% (49,944,400 mg L^?1 and 917 NTU) of turbidity and 4100.00% of phenol when compared to dyeing wastewater of other fibers. Other parameters such as pH, alkalinity, color, phosphorus, nitrogen, sulfides, chlorides, oil and grease, dissolved solids, and chemical and biochemical oxygen demand were also assessed. In addition to individual characterization, this study also presents a correlation of the contribution of each parameter to the final textile effluent. Although dyeing wastewater of polyamide contributes the most in terms of quantity for the final effluent, this study revealed that dyeing wastewater of polyester influenced the most on the final composition of the textile wastewater when evaluating color, turbidity, total iron, biochemical oxygen demand, chemical oxygen demand, phenol, mercury, oil and grease, and total phosphorus. The present study is focused on bringing new insights to provide future research with other strategies to improve the treatment of dyeing wastewater. In addition, some suggestions are also given for wastewater treatments according to type of textile fiber.