轻柴油储罐火灾过程及安全性评价

从 2 0 0 2年 1月 1日起我国实施新的“轻柴油”产品标准 ,新标准将轻柴油的闪点指标由原来的≥ 65℃改为≥ 5 5℃ ,由此导致轻柴油的火灾危险类别发生变化 ,并进而引发原有轻柴油储罐能否安全储存新标准轻柴油的问题。笔者利用化学流体力学模型和挪威船级社 (DNV)的SAFETI风险评估软件对 65℃闪点和 5 5℃闪点轻柴油的储存火灾危害性进行了评估 ,取得了轻柴油火灾中危害程度的计算机模拟结果     

INTERACTIVE DISTRIBUTED CONSERVATION PLANNING1

ABSTRACT: In the environmental and agricultural conservation planning process, more efficient and effective tools are needed for planners to assist private landowners with making wiser land use decisions. Current methods are slow, inefficient, and costly. Scientific techniques have not been fully implemented within the planning process, yet such plans are increasingly needed to meet water quality and Total Maximum Daily Load (TMDL) requirements. The objectives of this study are to (a) utilize the web for accessing an integrated science‐based land use decision support system; (b) link decision tools, models, and databases to the user via the web; (c) link distributed models and databases for enhanced planning efficiency; and (d) integrate the above into an easily usable and readily accessible system. The procedures resulting in the initial design involved planning expertise and focus groups' input. The system was developed in partnership with the Natural Resources Conservation Service of the U.S. Department of Agriculture and several state agencies. A survey of 150 certified conservation planners, the end users, was conducted to identify the data sets and planning tools needed. Data, tools, and models then were selected and integrated into a web accessible system. Specifically, the first generation used a web interactive Geographic Information System (GIS) that overlaid onto digital orthoquads and/or soils polygons field boundaries, transportation, hydrologic features (such as drains, rivers, lakes, etc.), and high pesticide risk runoff or infiltration areas. Conservation planners found they could save time with the system. Clients could access the system quickly to help them prepare for meeting with their planner. Previously acquiring GIS maps in some cases had been a lengthy process that limited use of the information in land use decisions.     

ECONOMIC INCENTIVES FOR AGRICULTURAL NONPOINT SOURCE POLLUTION CONTROL1

ABSTRACT. The limited success of command-and-control policies for reducing nonpoint source (NPS) water pollution mandated under the Federal Water Pollution Control Act (FWPCA) has prompted increased interest in economic incentive policies as an alternative control mechanism. A variety of measures have been proposed ranging from fairly minor modifications of existing policies to substantial revisions including watershed-wide polices that rely on economic incentives. While greater use of economic incentive policies, such as environmental bonds and point/nonpoint source trading is being advocated in the reauthorization of the CWA, the expected effects of individual proposals will be modest. The characteristics of NPS pollution, namely uncertainty and asymmetrical information, underscores that there is no single, ideal policy instrument for controlling the many types of agricultural NPS water pollution. Some of the usual incentive-based policies, such as effluent taxes, are not well suited to the task. Individual incentive policies proposed for the reauthorized CWA, such as pollution trading or deposit/refund systems, are not broadly applicable for heterogeneous pollution situations. Economic incentive policies may be appropriate in some cases, and command-and-control policies will be preferable in others and may in fact complement incentive policies.     

AREWIDE WATER QUALITY MANAGEMENT IN AN ENERGY DEVELOPMENT AREA1

ABSTRACT: A Section 208, Areawide Waste Treatment Management Project, is attempting to develop an implementable water quality management plan for an energy impacted area. Staff members and consultants are investigating point and nonpoint sources. On a short-term basis, population growth and construction will have a greater impact on water quality than strip mining.     

COMPUTER APPLICATION TO DOUBLE-MASS ANALYSIS1

ABSTRACT: Double-mass analysis for checking consistency of a hydrological record is considered to be essential before taking it for analysis purpose. Because of increasing computer application in hydrological analyses, in the present paper, a simple and efficient method for the double-mass checking has been developed. The problem has been formulated in FORTRAN IV language and the basic steps and a computer output of the program are presented in a flow chart and a table.     

一种湿度试验中计算露点温度的方法

目的研究在气候环境试验中如何把露点温度作为控制目标的方法。方法选择干湿球温度表作为测量湿度的传感器,饱和水汽压是计算湿度量的一个重要参数,探究出便于在微控制器上应用的计算饱和水汽压的公式,然后建立露点温度计算模型,得出水汽压与露点温度的关系式。结果通过0~100℃的100组样本值的验证,与《湿度查算手册》值比较,平均误差较小。结论该公式适用于湿度试验箱中微控制器中露点温度的处理问题。     

A Review of Water Quality Responses to Air Temperature and Precipitation Changes 2: Nutrients,Algal Blooms,Sediment, Pathogens

In this paper we review the published, scientific literature addressing the response of nutrients, sediment, pathogens, and cyanobacterial blooms to historical and potential future changes in air temperature and precipitation. The goal is to document how different attributes of water quality are sensitive to these drivers, to characterize future risk, to inform management responses, and to identify research needs to fill gaps in our understanding. Results suggest that anticipated future changes present a risk of water quality and ecosystem degradation in many United States locations. Understanding responses is, however, complicated by inherent high spatial and temporal variability, interactions with land use and water management, and dependence on uncertain changes in hydrology in response to future climate. Effects on pollutant loading in different watershed settings generally correlate with projected changes in precipitation and runoff. In all regions, increased heavy precipitation events are likely to drive more episodic pollutant loading to water bodies. The risk of algal blooms could increase due to an expanded seasonal window of warm water temperatures and the potential for episodic increases in nutrient loading. Increased air and water temperatures are also likely to affect the survival of waterborne pathogens. Responding to these challenges requires understanding of vulnerabilities, and management strategies to reduce risk.     

折点加氯法脱氨氮后余氯的脱除

焦化废水是指用煤制焦炭、煤气净化和焦化产品回收等焦化过程中煤中的吸附水及热反应的生成水冷凝后生成的。废水中含有高浓度的酚、氰、氨氮和多种有机化合物。A／O法处理焦化废水,脱氮效率受湿度等因素影响,变化较大,采用折点加氯法对水中氨氮进一步脱除,可使氨氮浓度降至10mg／L。本文在实验室条件下,根据已获得的氯投加量、pH值、搅拌及反应停留时间等最佳反应条件的基础上,探讨折点加氯法的处理效果,以及最佳的废水处理浓度,并寻求活性炭、焦炭脱除余氯的最佳条件,最终提出适合北方地区焦化废水的系统脱氮方案。     

农业生产面源污染控制探讨

就农业面源污染对农业可持续发展的影响，以及造成面源污染的原因进行了分析，从观念上、政策上、技术上对农业面源朽染控制做了一些探讨，以促进农村水环境保护和农业的可持续发展。     

农业面源污染模型研究进展

综述了农业面源污染模型国内外研究进展,介绍了常用的面源污染模型概念与适用范围,明确"3S"技术与SWAT、AGNPS等模型有机结合是当今面源污染模型的研究热点。提出我国面源污染模型未来研究的重点是围绕水质改善目标,建立面向全流域尺度的面源污染负荷估算方法,构建完整的基础监测数据网络,为建立符合我国流域特性的面源污染模型提供支撑。