PREDICTIVE MODEL FOR NITRATE LOAD IN THE BULL RUN WATERSHED,OREGON1

ABSTRACT: Predictive models for nitrate in four streams in the Bull Run Watershed in the Cascade Mountains of Oregon were developed from a record of 17 years of nitrate samples. The models are time series regression models written in terms of Log(nitrate load). The independent variables are logarithm of 14-day mean daily stream discharge, current day's precipitation, logarithm of the previous day's precipitation, total precipitation for the previous seven days, a hydrograph position variable that indicates rising or falling limb, and average maximum air temperature for the preceding 14 days. The models describe annual cycle and seasonable trends and variations in nitrate load, but are unable to describe large day to day variations like those associated with hydrograph peaks.     

房地产开发项目环境影响评价的探讨

根据房地产开发项目的特点,阐述该项目施工期、运行期分别对环境产生的不良影响,着重分析施工期扬尘、运行期废水污染情况,以及减缓该不利影响的措施,最后总结房地产开发项目环境影响评价还须进一步探讨的问题。     

反应失控型火灾爆炸事故预测

介绍了一种预测反庆失控灾害的方法,通过实验测定容器的时间常数,预测能够引起反应失控的最低环境温度,发生反应失控时的危险温度,以及达到最大反应速度反需的时间,预测结果与实际情况具有良好的一致性。     

A SYSTEMATIC ANALYSIS OF THE CONSTRAINTS TO URBAN STREAM ENHANCEMENTS1

ABSTRACT: The environment surrounding urban streams imposes constraints upon stream enhancement projects. Constraints include bridges, culverts, highways, sewer and water lines, lack of easements, and other floodplain structures. The consequences of failure of these infrastructure constraints can be significant and should be considered in the design process. Fault tree analysis provides a systematic technique for analyzing the interactions of events that could lead to infrastructure failure. A case study of a stream in Pittsburgh, Pennsylvania, shows that fault tree analysis can effectively model the interactions between the stream system and the infrastructure constraints and predict the most likely modes of failure. In addition, the relative success of alternative designs and failure mitigation techniques can be assessed using this analysis tool, lending insight into the urban stream enhancement design process. The method could also provide justification in the design permitting process and input for risk assessment.     

含硫污水汽提装置运行与改造分析

详细介绍了原污水汽提装置的工艺及运行状况，对影响装置汽提运行效果的几方面因素逐一进行了分析，找出了汽提效果差的主要原因，指出了解决问题的对策。通过改造，解决了原装置所存在的问题，装置处理量、污染物去除效果大大提高，基本达到了设计要求     

中原地区旱涝等级预测──利用游程理论和王邨重建的2232a降水距平资料

本文采用王重建的２２３２ａ降水长序列运用Ｍａｒｋｏｖ过程理论分析了中原各地区旱涝等级的概率特征；定义了净旱涝历时、净旱涝烈度、平均净旱涝烈度参量，并用之建立了中原中心区降水的丰枯段等级预测模式。为中原地区旱涝分析和预测提供了理论依据。