锅炉烟尘测试中锅炉负荷率的计算方法探讨

GB5468 -91规定 ,锅炉烟尘测试时 ,必须对锅炉的运行负荷进行测试 ,而实际监测过程中 ,许多锅炉房不具备测试的计量条件 ,为了解决这一问题 ,文章提出利用烟气量和空气过剩系数计算锅炉负荷率。在实际监测工作中 ,该方法方便、易于操作 ,所得结果和标准规定方法所得结果有很好的一致性     

城市空气质量周报效用分析

介绍了世界上一些发达国家的空气污染预报的做法和采取的措施,阐述了我国开展空气质量预报的方针和方法,指出了周报是预报的基础工作。叙述了我国空气质量周报的污染参数的选取、污染指数的分级及其浓度限值和污染指数计算及确定,分析并总结了开展城市空气质量周报所发挥的效用是提高公众的环保意识,加大了治理污染的力度,转变了环境监测的职能,促进了环境监测事业的发展     

水中总硬度测量不确定度的评定

采用EDTA滴定法测定水质总硬度的测量不确定度评定。充分考虑测量重复性、标准溶液的配制、滴定等过程对测量的影响,计算水中总硬度的测量相对合成标准不确定度为1·81×10-3。     

贵州黔东南州三板溪水库春季拟多甲藻水华特征

2011年3月13日对贵州省黔东南州三板溪水库进行春季浮游植物调查的结果表明,三板溪水库Ⅱ号采样点(下革东)发生以佩纳形拟多甲藻为优势种的拟多甲藻水华,细胞密度高达1.15×10⁷cell/L;板溪水库总氮的最低值为2.09 mg/L,总磷的最低值为0.95 mg/L,三板溪水库的总氮、总磷含量较丰富,不存在总氮或总磷是限制性因子;通过SPSS16.0统计软件分别进行Pearson 积距相关系数分析表明,氮磷比是三板溪水库发生拟多甲藻水华的主要影响原因。     

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.     

二乙氨基二硫代甲酸银试剂质量对测砷的影响

用简单合成了二乙氨基二硫代甲酸银试剂，并比较了自制和市售的二乙氨基二硫人 银对测砷的影响。结果表明，采用自制的二乙氨基二硫代甲酸银能大大降低试剂空白，提高方法的灵敏度和降低检出限，试剂质量明显优于市售产品。     

氨氮测量不确定度的评定

采用纳氏试剂光度法测定水质氨氮的测量不确定度评定,应该考虑工作曲线、测量重复性、标准溶液、仪器读数分辨率等对测量的影响.     

Fractionation of heavy metals and assessment of contamination of the sediments of Lake Titicaca

Chemical weathering is one of the major geochemical processes that control the mobilization of heavy metals. The present study provides the first report on heavy metal fractionation in sediments (8–156 m) of Lake Titicaca (3,820 m a.s.l.), which is shared by the Republic of Peru and the Plurinational State of Bolivia. Both contents of total Cu, Fe, Ni, Co, Mn, Cd, Pb, and Zn and also the fractionation of these heavy metals associated with four different fractions have been determined following the BCR scheme. The principal component analysis suggests that Co, Ni, and Cd can be attributed to natural sources related to the mineralized geological formations. Moreover, the sources of Cu, Fe, and Mn are effluents and wastes generated from mining activities, while Pb and Zn also suggest that their common source is associated to mining activities. According to the Risk Assessment Code, there is a moderate to high risk related to Zn, Pb, Cd, Mn, Co, and Ni mobilization and/or remobilization from the bottom sediment to the water column. Furthermore, the Geoaccumulation Index and the Enrichment Factor reveal that Zn, Pb, and Cd are enriched in the sediments. The results suggest that the effluents from various traditional mining waste sites in both countries are the main source of heavy metal contamination in the sediments of Lake Titicaca.     

Evaluation of method of preparation of passive diffusion tubes for measurement of ambient nitrogen dioxide

This study was carried out in response to suggestions that the measurement of NO(2) by Palmes-type passive diffusion tubes (PDT) is affected by the method of preparation of the triethanolamine (TEA) absorbent coating on the grids. The following combinations of factors were investigated: TEA solvent (acetone or water), volume composition of TEA in solvent (50% or 20%), and grid coating method (dipping in solution prior to assembly or pipetting solution on after assembly). Duplicate PDTs prepared by each of the 8 methods were exposed in parallel, in urban air, for a total of 80 separate 1 week exposures. NO(2) concentrations derived from PDTs prepared by pipetting methods were significantly less precise than concentrations from dipping methods, with mean RSDs for duplicate measurements of 13.8% and 8.5%, respectively (n= 316 each category). Pipetting methods using solutions of 50% TEA composition were particularly imprecise (mean RSD 17.2%). Data from PDTs prepared by pipetting methods were systematically more poorly correlated with each other and with data from co-located chemiluminescence analysers, than corresponding data from PDTs prepared by dipping methods, indicating that more consistent accuracy was also obtained by the latter PDTs. The statistical evidence suggested that PDTs prepared by pipetting 50% TEA in water generally gave lower NO(2) concentrations. Although this is in agreement with a previous study, it is also possible that such an observation here may be a statistical artefact given the demonstrably poorer precision of this method. The general tendency of PDTs to show positive bias in NO(2) measurement in urban air in 1 week exposures was again evident in this study (mean biases at roadside and urban centre locations of +35% (n= 475) and +18% (n= 112), respectively) consistent with augmentation of within-tube NO(2) flux by chemical reaction between co-diffusing NO and O(3). Overall, it is recommended that the pipetting method of PDT grid preparation is avoided, or at least investigated further, because of the apparent degradation in precision and accuracy of NO(2) measurement. Potential reasons for the effect are discussed.     

污染物总量控制中载体水流量的测定

示踪剂法测定河水流量是较为准确的办法 ,利用河流动力模型计算出示踪剂投放点 ,利用示踪剂投放量与测定浓度之间的关系可方便地获得河水流量结果     

实验室质量管理体系内部审核的实施

在实施GB/T15481-2000 idt ISO/IEC17025:1999标准《检测和校准实验室能力的通用要求》的过程中,通过实验室质量管理体系内部审核的实践与系统分析,识别出内部审核实施阶段的关键环节,提出召开首次会议、收集审核证据、确定审核发现和召开末次会议的技术方法,对提高内部审核的质量和有效性、获得可靠的审核结论具有重要意义。     

“湖泛”恶臭物质分析及来源浅析

介绍了中国南方"湖泛"中的恶臭物质及检测情况,采用常规分析和气相色谱-质谱(GC-MS)对"湖泛"水样进行检测,认为"湖泛"恶臭物主要是氨和硫醚类物质。根据"湖泛"发生的时间及频次,结合南方地区农业水稻秧田的农药使用情况,推断氨基甲酸酯类农药的使用可能是"湖泛"发生的诱因。     

实验室质量管理体系内部审核的策划

在实施GBT15481-2000(idtISOIEC17025:1999)标准《检测和校准实验室能力的通用要求》的过程中,通过实验室质量管理体系内部审核的实践与系统分析,识别出内部审核策划阶段的关键环节,提出审核范围确定、审核计划和抽样方案制订的技术方法,为有序高效地实施内部审核提供了行动指南。     

污染源监测报告有效期问题的探讨

环境监测是环境管理的基础性工作,污染源监测报告(数据)的有效性是保证环境执法严肃、公正的重要条件,也是是守法企业展示良好社会形象的基本保证。依照国家的相关规定,并结合行业技术规范的要求,探讨污染源监测报告的有效期问题,以利于相关各方严肃、科学、合理地使用污染源监测数据。     

CN-测定中显色剂配制方法的选择与保存时间

对2种氰化物显色剂配制方法进行了对比，发现用无水乙醇配制的显色剂具有方便，经济，实用，无毒且显色剂保存期长等优势。     

Assessment of the efficiency and economic viability of various methods of treatment of sanitary landfill leachate

This study assesses the efficiency of various physico-chemical, biological and other tertiary methods for treating leachate. An evaluation study on the treatability of the leachate from methane phase bed (MPB) reactor indicated that at an optimum hydraulic retention time of 6 days, the efficiency of the reactor in terms of biological oxygen demand (BOD) and chemical oxygen demand (COD) removal was 91.29 and 82.69%, respectively. Recycling of the treated leachate through the municipal solid waste layers in the leachate recycling unit (LRU) resulted in a significant increase in the biodegradation of organics present in the leachate. Optimum BOD and COD removal efficiencies were achieved at the third recycle; additional recycling of the leachate did not produce any significant improvement. Physico-chemical treatment of the leachate demonstrated that alum and lime (Option 2) were more economical than coagulants lime and MgCO₃. A cost analysis of the economics of the various treatments revealed that the alternative treatment consisting of a MPB bed followed by a LRU and aerated lagoon is the most cost-effective treatment. However, the alternative consisting of a MPB followed by the LRU and a soil column, which is slightly more costly, would be the most appropriate treatment when adequate land is readily available.     

液氯泄漏事件的环境安全防护距离与监测布点方法

以大气湍流扩散模型为基础,结合大气环境基本资料和氯气的性质,提出了氯气泄漏突发事件的应急防护范围,为发生类似事件时的人群撤离范围和布点监测、监控范围,提出了一种思路,供大家参考.     

Modeling of population dynamics of interacting species: effect of exploitation

A model representing the predator‐prey interactions between two copepod species, Euterpina acutifrons and Temora stylifera, with unlimited resources was used to study effects of exploitation. Exploitation is modeled by harvesting strategies characterized through three parameters: the selectivity of gear, the frequency of harvest, and the intensity of harvest effort. Simulations of different harvesting strategies suggest that interactions between species influence the dynamic behaviors of the populations as well as harvesting yields.     

Investigation of impact of environmental changes on precipitation pattern of Pakistan

In this paper, variability in precipitation pattern of Pakistan due to environmental and climatic changes has been studied. Maps have been generated to depict global precipitation variation. Precipitation data of 25 stations of Pakistan have been used. These data were taken from Meteorological Department, Islamabad, Pakistan. The results of two global climate models, namely Australia’s Commonwealth Scientific and Industrial Research’s third generation general circulation model and National Center for Atmospheric Research’s first generation precipitation circulation model for A2 scenario have been applied to investigate the changes. It is observed that precipitation pattern will change significantly in the future. The occurrence of precipitation in all seasons for Pakistan is expected to increase with almost uniform distribution across a season. Average annual precipitation of the country will undergo an increase in the range of +57 to +71 % as compared to average of the base period.     

新疆河流径流特征分析

选择了新疆众多河流中代表性好的7条河流，对径流的特征进行了分析。结果表明，新疆河流径流量主要集中在夏季，占年径流量的50．8％—70．7％，春、秋季径流量差别不大，冬季仅占年径流量的4．7％—10．8％。以7条河流径流深值可看出，北疆径流深值比南疆大，最大的是布尔津河，径流深为507．4mm。从径流量的Cv值看，除头道沟为0．44，极值比4．42较大外，其它河流的Cv值均在0．19—0．23间、极值比在1．85—2．42间。同时，新疆大多数河流径流量90年代后有明显增多的趋势。