城市固体废物处理处置设施恶臭污染评估指标体系研究

基于恶臭物质的嗅阈值,建立了针对城市固体废物处理处置设施的恶臭污染评估指标体系,重点包括基于阈稀释倍数的理论臭气浓度及其计算方法,指标恶臭物质的筛选方法,以及反映嗅觉感受的臭气指数及其计算方法等.并通过生活垃圾填埋场和中转站恶臭物质监测结果,展示了该指标体系在固体废物处理设施恶臭污染评估中的应用,为恶臭污染的预测,模拟与评估提供了定量化的科学方法.     

基于门限极值理论的湖泊水质参照状态的确定

在前人工作的基础上,利用门限极值的广义Pareto分布理论和超出阈值峰(Peak Over Threshold,POT)方法,提出了一种确定湖泊参照状态浓度的新方法.该方法不仅能够给出更为精确的置信区间,而且克服了广义极值分布理论取用数据浪费等缺陷.将该方法应用到太湖的水质基准参照状态中,通过POT方法对太湖8个站点1995~2006年总氮(TN),总磷(TP)和叶绿素a(Chl-a)的数据进行预处理,分别以-1.0mg/L, -0.05mg/L与-4μg/L作为它们观测值相反数的门限值,结果表明观测值的相反数符合广义Pareto分布,验证了方法的可行性.推荐采用25%分位点的值作为太湖总氮,总磷和叶绿素a的参照状态,即太湖的参照状态是:总氮0.66mg/L;总磷0.023mg/L;叶绿素a为1.27μg/L.最后分别得出了它们各自的95%置信区间,而且其精度明显高于广义极值分布理论结果.     

自然资源与经济增长——基于金融发展门槛效应

“资源诅咒”是经济学中的一个经典假说,但金融发展水平对“资源诅咒”产生的影响却容易被忽视。论文通过使用1996—2012年中国31个省市区域的面板数据,利用Hansen门槛模型发现：“资源诅咒”确实存在于中国省际;金融发展水平对经济增长存在门槛临界,即金融业的发展情况在门槛值1.635 2的前后,自然资源对经济增长的影响程度显著不同;居民消费和政府支出可以显著影响金融业的发展;物质资本投入水平仍然是影响中国经济增长的重要因素。因此拉动地方消费、提高政府支出和物质资本投入,进而提高地区金融业发展水平,可以有效缓解“资源诅咒”现象,促进经济增长。     

Dilution with air to minimise consequences of toxic/flammable gas releases

Dilution has long been considered a solution to many problems of toxic/flammable material releases. It implies diluting to a concentration that is below physiologically dangerous levels for a toxic substance (generally below TLV), or to a level below LFL for a flammable material release, ensuring that the process adopted for dilution does not itself enhance the risks.

In this paper, we discuss the dilution of a gaseous release by deliberate and cautious mixing with air to reduce its concentration to a harmless level. The idea bears its origin to the Bhopal Gas Tragedy where some families saved themselves by turning the ceiling fans on when MIC reached their bedrooms at the dead of very cold night on December 2–3, 1984. The air pushed in by the fans diluted the MIC to below the harm level.

Some of the advantages of using air dilution are: no cost of air, no air storage needed, no need to treat the air after use as in case of water curtains; required equipment, its maintenance and staff training in its use are very likely to cost less than in other ways of handling a release.

Air dilution may not be feasible in all cases, such as gaseous release within a congested equipment layout, release that forms a liquid pool, etc. The method needs to be evaluated for each case.     

STREAMFLOW MEASUREMENT USING SALT DILUTION IN TUNDRA STREAMS,NORTHWEST TERRITORIES,CANADA1

ABSTRACT: With the recent increased exploration and mining activity in the Northwest Territories, there has been growing interest in streamflows. However, streamflow monitoring in Canada's north is limited, especially in the central Northwest Territories where the exploration activity is concentrated. To complicate matters, the standard approach of measuring discharge with current meters or weirs is often inadequate or prohibitively expensive, as many streams in the region are shallow, braided and rocky. In response, alternative techniques such as salt dilution can be used. A salt tracer's competence in turbulent and rocky channels makes it ideal for discharge measurements in these situations. This paper summarizes the work performed by Indian and Northern Affairs Canada and Canamera Geological Ltd. staff in determining the stream discharge of a lake outlet using a potassium chloride (KC1) tracer. A variety of streamflow measurement methods were performed and compared to determine the viability and rigor of the dilution method. Results suggest the dilution method compares favorably to other measurement techniques both in accuracy and operational ease.     

ENVIRONMENTAL THRESHOLD FUNCTIONS FOR USER ORIENTED RESOURCE PLANNING AND MANAGEMENT1

ABSTRACT: Managers of water related outdoor recreation resources want to provide facilities and recreational opportunities of high quality that are attractive to recreationists. The reported research develops a relevant site quality assessment and measurement procedure called environmental threshold modeling. This modeling procedure is based upon the idea that individuals (i.e., recreationists) have specific, identifiable evaluative criteria which can be expressed as a mathematical function of various site characteristics. The function of interest is called a threshold function because it separates acceptable recreational settings from unacceptable settings. Individual specific threshold functions can be easily aggregated to form a population specific threshold function that estimates the proportion of a population that would find the recreational setting acceptable for some specific activity. Presented in this paper are illustrative calibration results based upon survey data collected from recreational canoeists using the Pine River in Michigan's Manistee National Forest.     

我国与国际空气污染指数系统的比较

通过对中国内地、中国香港、韩国和美国的空气污染指数系统进行比较,结果发现,中国内地API系统在污染分级描述、数据的时空代表性、污染物种类和污染分级的浓度限值等方面与其他系统存在很大的差别.同时,以珠三角区域空气质量监控网的天湖、万顷沙和荃湾3个站点2005～2007年的数据为依据,评价了在中国现行的评级系统中加入O3和PM2.5对API水平和首要污染物的影响,并讨论了采用不同的污染物浓度限值对臭氧和颗粒物分指数的影响,最后从科学研究和环境管理的角度论述了修订我国API评级系统的必要性.     

HJ505-2009法测定生化需氧量[BOD_5]不确定度评定

测量不确定度（uncertainty of measurement）是表征合理地赋予被测量之值的分散性,与测量结果相联系的参数。不确定度一词指可疑程度,广义而言,测量不确定度是对测量结果正确性的可疑程度。如何对测量结果的不确定度进行合理评定,一直是困扰检测实验室的一个难题。依据HJ505—2009标准的方法,测定了水样的生化需氧量BOD5,估算了测试过程中的随机效应和系统效应所产生的不确定度分量,最终评定了生化需氧量浓度的测量不确定度。