以R22／R152a混合新工质替代R12——氟利昂制冷技术的新工艺

通过对几种主要制冷工质的研究分析，对众多的替代工质进行比较选择，确定了Ｒ２２与Ｒ１５２ａ两种混合物近共沸混合的作为替代Ｒ１２的新工质，并对制冷系统进行了优化设计，通过制冷性能分析比较，能耗分析比较，工艺性比较，维修性比较，成本效益分析比较和新工质配套供应能力分析，用Ｒ２２／Ｒ１５２ａ混合工质替代Ｒ１２对防止大气臭氧层破坏是可行的，节能效果显著，对环境的污染降低到最低水平。     

对国标中石油类和动植物油红外光度法测定的几点探讨

通过大量的对实际样品的实验分析和作者本人多年的实践经验，对国标中水质石油类和动植物油的红外分光光度法分析标准提出几点探讨说明，并对该方法做了部分修改，已应用于实际分析工作中，效果不错．     

精密度——偏性分析质量控制试验在石墨炉原子吸收法中的应用

采用电热原子吸收法测定水质中微量元素铅，并利用精密度——偏性分析质量控制试验，对其分析的方法进行了全面质量控制与评价，结果表明对低含量的测定(小于5μg／L)分析结果，精密度及准确度较差，但在可接受范围，其分析结果可能受到环境条件及干扰因素的影响．     

焦作市区大气污染状况与防治措施

根据“九五”期间焦作市区的大气污染监测资料，对市区大气污染状况进行了分析和评价，并对其成因进行了分析，提出了一些具体的防治措施。     

染料废水的X射线粉末衍射分析

染料生产过程的废水，其中含有致癌，致畸的有毒物质，通常需经生化处理后才排放，但生化处理并不能使其毒性消除骀尽，所以对处理后排放废水的进一步分析是当今环保分析中的一个重要课题，分光光度法，高压液相色谱及色－质联用仪是作微量分析的常用方法，但难以分析难挥发物和悬浮物，我们尝试用Ｘ射线粉末衍射分析法对分离废水得到的固态难挥发物作了分析，证明此法准确，快捷，可推广，但对胶状物或含量过低的物质则不适用。     

对环境质量综合分析工作的思考与建议

概述了环境质量综合分析对环境管理与综合决策的重要性，分析了环境质量综合分析工作现状与存在问题，阐述了新时期对综合分析工作的新要求，从创新理念、主动服务、收集信息、强化手段、健全机制、人才培养等方面提出做好环境质量综合分析，服务环境管理与决策的建议。     

宝鸡市机动车尾气排放现状调查与分析

通过对宝鸡市区机动车尾气排放检测数据的比较分析，基本摸清了机动车尾气排放现状及规律，并对尾气超标原因作了分析，提出了控制和减少尾气污染的对策．     

乌鲁木齐地下水氮的分布及成因研究

对乌鲁木齐市地下水进行了分区取样，对氮的分布形式及特征进行了分析研究，通过统计计算及分析，对成因进行了推断，得出初步结论：人口密集区氮的含量与大气污染及人的活动有关。     

铁岭市大气中二氧化硫污染趋势分析

依据环境监测基础数据，分析，评价了铁岭市二氧化硫污染现状状，对二氧化硫污染变化趋势进行了系统分析。     

二氧化硫分析中的关键事项

文中对多次分析二氧化硫得出的经验进行了总结，指出了二氧化硫分析中的关键事项，并且在步骤上有所简化，可供有关人员借鉴。     

Atmospheric Change and Biodiversity in the Arctic

The Canadian Arctic is characterized by a high variation in landform types and there are complex interactions between land, water and the atmosphere which dramatically affect the distribution of biota. Biodiversity depends upon the intensity, predictability and scale of these interactions. Observations, as well as predictions of large-scale climate models which include ocean circulation, reveal an anomalous cooling of northeastern Canada in recent decades, in contrast to the overall significant increase in average annual temperature in the Northern Hemisphere. Predictions from models are necessary to forecast the change in the treeline in the 21st century which may lead to a major loss of tundra. The rate of change in vegetation in response to climate change is poorly understood. The treeline in central Canada, for example, is showing infilling with trees, and in some locations, northerly movement of the boundary. The presence of sea ice in Hudson Bay and other coastal areas is a major factor affecting interactions between the marine and terrestrial ecosystems. Loss of ice and therefore hunting of seals by polar bears will reduce bear and arctic fox populations within the region. In turn, this is likely to have significant effects on their herbivorous prey populations and forage plants. Further, the undersurface of sea ice is a major site for the growth of algae and marine invertebrates which in turn act as food for the marine food web. A rise in sea-level may flood coastal saltmarsh communities leading to changes in plant assemblages and a decline in foraging by geese and other consumers. The anomalous cooling in the eastern Arctic, primarily in late winter and early spring, has interrupted northern migration of breeding populations of geese and ducks and led to increased damage to vegetation in southern arctic saltmarshes as a result of foraging. It is likely that there has been a significant loss of invertebrates in those areas where the vegetation has been destroyed. Warming will have major effects on permafrost distribution and on ground-ice resulting in a major destabilization of slopes and slumping of soil, and disruption of tundra plant communities. Disruption of peat and moss surfaces lead to loss of insulation, an increase in active-layer depth and changes in drainage and plant assemblages. Increases of UV-B radiation will strongly affect vulnerable populations of both plants and animals. The indigenous peoples will face major changes in life style, edibility of food and health standards, if there is a significant warming trend. The great need is for information which is sensitive to the changes and will assist in developing an understanding of the complex interactions of the arctic biota, human populations and the physical environment.     

合肥市环巢湖地区种植业面源污染监测与评价

通过2016-2018年在合肥市环巢湖5个县区主要农田周边沟渠中采集水样,监测农田氮磷流失浓度,并评价该区域种植业面源污染状况。结果表明,这3年该区域种植业TN、TP流失的平均质量浓度分别为3.48 mg/L、0.602 mg/L,均高于地表水Ⅴ类水质标准。2016年与2017年TN、TP浓度差异不大,2018年较前两年TN浓度有所提高,TP浓度相比显著降低。巢湖市农田沟渠水中TP浓度高于其他县区,TN浓度相对较低;NO-3 N浓度庐江县高于其他县区;NH 3 N地区间几乎没有差异。TP和NH 3 N浓度均为秋季高于夏季,TN和NO-3 N浓度均为夏季高于秋季。     

Distribution of Iron, Manganese, Zinc and Atrazine in Groundwater in Parts of Palar and Cheyyar River Basins, South India

A study was carried out in a part of Palar and Cheyyar river basin to evaluate the current status of iron, manganese, zinc and atrazine concentrations, their origin and distribution in groundwater. Groundwater samples were collected during post-monsoon (March 1998 and February 1999) and pre-monsoon (June 1999) periods from 41 sampling wells distributed throughout the study area. The groundwater samples were analyzed for trace metals using AAS and atrazine using HPLC. The concentration of the trace elements in groundwater is predominant during pre-monsoon period. Distribution pattern indicates that the concentration of these elements increases from west to northeast and towards Palar river. Lower concentrations in the central part may be due to recharge of fresh water from the lakes located here. During most of the months, as there is no flow in Palar river, the concentrations of trace elements in groundwater are high. Drinking water standards indicate that Mn and Zn cross the permissible limit recommended by EPA during the pre-monsoon period. A comparison of groundwater data with trace element chemistry of rock samples shows the abundance of trace elements both in the rock and water in the order of Fe > Mn > Zn and Fe > Zn > Mn. This indicates that iron in groundwater is derived from lithogenic origin. Further, Fe, Mn and Zn have good correlation in rock samples, while it is reverse in the case of water samples, indicating the non-lithogenic origin of Mn and Zn. Atrazine (a herbicide) was not detected in any of the groundwater samples in the study area, perhaps due to low-application rate and adsorption in the soil materials.     

Effects of Copper Sulfate and Copper Nitrate in Aquatic Medium on the Restoration Potential and Accumulation of Copper in Stem Cuttings of the Terrestrial Medicinal Plant, Portulaca Oleracea Linn

The stem cuttings of the terrestrial, ornamental plant, Portulaca oleracea, grew well in distilled water by producing adventitious roots and leaves. However, when exposed to various concentrations of sulfate and nitrate salts of copper resulted in a suppression of root growth, increase in initiation time of roots and sprouts and decay of stem cuttings from the cut open end, decrease in number of leaves with an increase in concentration of copper in the growth medium. Accumulation of copper increased with increasing concentrations of both copper sulfate and copper nitrate. However, copper accumulation was greater in copper nitrate than in copper sulfate treatment. Hence, copper in the presence of nitrate is more toxic than in the presence of sulfate. The accumulation factors in all treatment concentrations were greater than 1, hence P. oleracea is a copper accumulator.     

Biomonitoring of Lead, Zinc, and Cadmium in Streams Draining Lead-Mining and Non-Mining Areas, Southeast Missouri, USA

We evaluated exposure of aquatic biota to lead (Pb), zinc (Zn), and cadmium (Cd) in streams draining a Pb-mining district in southeast Missouri. Samples of plant biomass (detritus, periphyton, and filamentous algae), invertebrates (snails, crayfish, and riffle benthos), and two taxa of fish were collected from seven sites closest to mining areas (mining sites), four sites further downstream from mining (downstream sites), and eight reference sites in fall 2001. Samples of plant biomass from mining sites had highest metal concentrations, with means 10- to 60-times greater than those for reference sites. Mean metal concentrations in over 90% of samples of plant biomass from mining sites were significantly greater than those from reference sites. Mean concentrations of Pb, Zn, and Cd in most invertebrate samples from mining sites, and mean Pb concentrations in most fish samples from mining sites, were also significantly greater than those from reference sites. Concentrations of all three metals were lower in samples from downstream sites, but several samples of plant biomass from downstream sites had metal concentrations significantly greater than those from reference sites. Analysis of supplemental samples collected in the fall of 2002, a year of above-average stream discharge, had lower Pb concentrations and higher Cd concentrations than samples collected in 2001, near the end of a multi-year drought. Concentrations of Pb measured in fish and invertebrates collected from mining sites during 2001 and 2002 were similar to those measured at nearby sites in the 1970s, during the early years of mining in the Viburnum Trend. Results of this study demonstrate that long-term Pb mining activity in southeast Missouri has resulted in significantly elevated concentrations of Pb, Cd, and Zn in biota of receiving streams, compared to biota of similar streams without direct influence of mining. Our results also demonstrate that metal exposure in the study area differed significantly among sample types, habitats, and years, and that these factors should be carefully considered in the design of biomonitoring studies.     

A Note on the Use of Conservation Practices in U.S. Agriculture

This article measures the effect of an increase in productivityattributable to an increase in soil organic carbon associated with theincrease in the use of conservation practices in agriculture in theUnited States. Both the direct and indirect effects are calibrated. Theanalytical approach used consists of a dynamic computable generalequilibrium model composed of 14 producing sectors, 10 consumingsectors, seven household categories classified by income, and agovernment. The results suggest that the impact of a change inproductivity is an increase in output over a six year period starting in1998 in field crops. The most significant impact is felt in thelivestock sector. This is because field crops are a major input in theproduction of livestock. The food processing sector also exhibits arelatively large increase because of the increase in inputs of both fieldcrops and livestock. Manufacturing output increases primarily becauseoverall investment rises and most investment utilizes manufacturinggoods. The other producing sectors are generally unaffected by theincrease in agricultural production due to an increase in soil organiccarbon. Coincident with the increase in the production of field cropsis a relatively large decrease in the price of field crops. Othernoticeable price reductions occur in the livestock sector and the foodprocessing sector. For the consuming sectors, the consumption offood and alcohol and tobacco increase but consumption in all of theother sectors remains basically unchanged. Prices in the food andalcohol and tobacco sectors decline by about 1% while theprices in the other sectors remain static. Household welfare increasesin the aggregate by only 0.1% with this increase occurringuniformly across all household categories. Revenue received by thegovernment increases a modest 2% in response to an increase inoutput and, hence, an increase in taxes paid. The results indicate thatthere are significant production benefits for several sectors that can berealized by an increase in the use of conservation practices inagricultural production which, in turn, enhances soil organic carbon.There are a number of policy options available to promote the use ofconservation practices. These include education and technicalassistance, financial assistance, research and development, landretirement, and regulation and taxes.     

江苏省茶园和农田土壤中拟除虫菊酯类农药残留与污染特征分析

于2018年4—6月采集了江苏省10个市的茶园和农田表层土壤样品,采用气相色谱-三重四级杆质谱仪分析样品中12种拟除虫菊酯类农药的质量比和组成。结果表明,江苏省茶园和农田土壤中广泛检出拟除虫菊酯类农药,总量分别为27.1~50.7,56.9~97.0 ng/g。研究区域的拟除虫菊酯类农药含量存在差异,但组成相近,均是高效氯氟氰菊酯和联苯菊酯的比例较高。与国内其他地区土壤相比,江苏省茶园和农田土壤中拟除虫菊酯含量处于中等水平。     

Biomonitoring in the Boulder River Watershed, Montana, USA: Metal Concentrations in Biofilm and Macroinvertebrates, and Relations with Macroinvertebrate Assemblage

Portions of the Boulder River watershed contain elevated concentrations of arsenic, cadmium, copper, lead, and zinc in water, sediment, and biota. We measured concentrations of As, Cd, Cu, Pb, and Zn in biofilm and macroinvertebrates, and assessed macroinvertebrate assemblage and aquatic habitat with the objective of monitoring planned remediation efforts. Concentrations of metals were generally higher in downstream sites compared with upstream or reference sites, and two sites contained metal concentrations in macroinvertebrates greater than values reported to reduce health and survival of resident trout. Macroinvertebrate assemblage was correlated with metal concentrations in biofilm and macroinvertebrates. However, macroinvertebrate metrics were significantly correlated with a greater number of biofilm metals (8) than metals in invertebrates (4). Lead concentrations in biofilm appeared to have the most significant impact on macroinvertebrate assemblage. Metal concentrations in macroinvertebrates were directly proportional to concentrations in biofilm, indicating biofilm as a potential surrogate for monitoring metal impacts in aquatic systems.     

Seasonal and Inter-Annual Variations in Methyl Mercury Concentrations in Zooplankton from Boreal Lakes Impacted by Deforestation or Natural Forest Fires

We compared the effects of natural and anthropogenic watershed disturbances on methyl mercury (MeHg) concentration in bulk zooplankton from boreal Shield lakes. MeHg in zooplankton was monitored for three years in nine lakes impacted by deforestation, in nine lakes impacted by wildfire, and in twenty lakes with undisturbed catchments. Lakes were sampled during spring, mid- and late summer. MeHg in zooplankton showed a seasonal trend: concentrations were the lowest in spring, then peaked in mid-summer and decreased in late summer. Over the three study years, MeHg concentrations observed in mid-summer in zooplankton from forest harvested lakes were significantly higher than in reference and fire-impacted lakes, whereas differences between these two groups of lakes were not significant. The pattern of distribution of MeHg in zooplankton during the different seasons paralleled that of dissolved organic carbon (DOC), which is known as a vector of Hg from watershed soils to lake water. Besides DOC, MeHg in zooplankton also showed a positive significant correlation with epilimnetic temperature and sulfate concentrations. An inter-annual decreasing trend in MeHg was observed in zooplankton from reference and fire-impacted lakes. In forest harvested lakes, however, MeHg concentrations remained higher and nearly constant over three years following the impact. Overall these results indicate that the MeHg pulse observed in zooplankton following deforestation by harvesting is relatively long-lived, and may have repercussions to the accumulation of MeHg along the food chain. Therefore, potential effects of deforestation on the Hg contamination of fish should be taken into account in forest management practices.     

宁波市颗粒物中多环芳烃浓度水平、分布及来源分析

讨论了2003年宁波市颗粒物中多环芳烃浓度水平、分布及来源,结果表明,PM10中PAHS占TSP中总量的83%,PM2.5中的PAHS占TSP总量的54%,颗粒物中多环芳烃主要存在于小于10μm的颗粒中。颗粒物中多环芳烃季节变化特征明显,夏季最低,冬季最高。汽车尾气对PM10中多环芳烃的贡献率达56%,汽车尾气是颗粒物中多环芳烃的主要来源。